text:
The Association Between Biological Subtype and Isolated Regional Nodal Failure After Breast-Conserving Therapy
Wo, Jennifer Y.; Taghian, Alphonse G.; Nguyen, Paul L.; Raad, Rita Abi; Sreedhara, Meera B.A.; Bellon, Jennifer R.; Wong, Julia S.; Gadd, Michele A.; Smith, Barbara L.; Harris, Jay R.
Purpose: To evaluate the risk of isolated regional nodal failure (RNF) among women with invasive breast cancer treated with breast-conserving surgery (BCS) and radiation therapy (RT) and to determine factors, including biological subtype, associated with RNF. Methods and Materials: We retrospectively studied 1,000 consecutive women with invasive breast cancer who received breast-conserving surgery and RT from 1997 through 2002. Ninety percent of patients received adjuvant systemic therapy; none received trastuzumab. Sentinel lymph node biopsy was done in 617 patients (62%). Of patients with one to three positive nodes, 34% received regional nodal irradiation (RNI). Biological subtype classification into luminal A, luminal B, HER-2, and basal subtypes was based on estrogen receptor status-, progesterone receptor status-, and HER-2-status of the primary tumor. Results: Median follow-up was 77 months. Isolated RNF occurred in 6 patients (0.6%). On univariate analysis, biological subtype (p = 0.0002), lymph node involvement (p = 0.008), lymphovascular invasion (p = 0.02), and Grade 3 histology (p = 0.01) were associated with significantly higher RNF rates. Compared with luminal A, the HER-2 (p = 0.01) and basal (p = 0.08) subtypes were associated with higher RNF rates. The 5-year RNF rate among patients with one to three positive nodes treated with tangents alone was 2.4%; we could not identify a subset of these patients with a substantial risk of RNF. Conclusions: Isolated RNF is a rare occurrence after breast-conserving therapy. Patients with the HER-2 (not treated with trastuzumab) and basal subtypes appear to be at higher risk of developing RNF although this risk is not high enough to justify the addition of RNI. Low rates of RNF in patients with one to three positive nodes suggest that tangential RT without RNI is reasonable in most patients.
Impact of Incidental Irradiation on Clinically Uninvolved Nodal Regions in Patients With Advanced Non-Small-Cell Lung Cancer Treated With Involved-Field Radiation Therapy: Does Incidental Irradiation Contribute to the Low Incidence of Elective Nodal Failure?
Kimura, Tomoki; Togami, Taro; Nishiyama, Yoshihiro; Ohkawa, Motoomi; Takashima, Hitoshi
Purpose: To evaluate the incidental irradiation dose to elective nodal regions in the treatment of advanced non-small-cell lung cancer with involved-field radiation therapy (IF-RT) and the pattern of elective nodal failure (ENF). Methods and Materials: Fifty patients with advanced non-small-cell lung cancer, who received IF-RT at Kagawa University were enrolled. To evaluate the dose of incidental irradiation, we delineated nodal regions with a Japanese map and the American Thoracic Society map (levels 1-11) in each patient retrospectively and calculated the dose parameters such as mean dose, D95, and V95 (40 Gy as the prescribed dose of elective nodal irradiation). Results: Using the Japanese map, the median mean dose was more than 40 Gy in most of the nodal regions, except at levels 1, 3, and 7. In particular, each dosimetric parameter of level 1 was significantly lower than those at other levels, and each dosimetric parameter of levels 10 to 11 ipsilateral (11I) was significantly higher than those in other nodal regions. Using the American Thoracic Society map, basically, the results were similar to those of the Japanese map. ENF was observed in 4 patients (8%), five nodal regions, and no mean dose to the nodal region exceeded 40 Gy. On the Japanese map, each parameter of these five nodal region was significantly lower than those of the other nodal regions. Conclusions: These results show that a high dose of incidental irradiation may contribute to the low incidence of ENF in patients who have received IF-RT.
Does Lymphovascular Invasion Predict Regional Nodal Failure in Breast Cancer Patients With Zero to Three Positive Lymph Nodes Treated With Conserving Surgery and Radiotherapy? Implications for Regional Radiation
Boutrus, Rimoun; Abi-Raad, Rita; Niemierko, Andrzej; Brachtel, Elena F.; Rizk, Levi; Kelada, Alexandra; Taghian, Alphonse G.
Purpose: To examine the relationship between lymphovascular invasion (LVI) and regional nodal failure (RNF) in breast cancer patients with zero to three positive nodes treated with breast-conservation therapy (BCT). Methods and Materials: The records of 1,257 breast cancer patients with zero to three positive lymph nodes were reviewed. All patients were treated with BCT at Massachusetts General Hospital from 1980 to December 2003. Lymphovascular invasion was diagnosed by hematoxylin and eosin-stained sections and in some cases supported by immunohistochemical stains. Regional nodal failure was defined as recurrence in the ipsilateral supraclavicular, axillary, or internal mammary lymph nodes. Regional nodal failure was diagnosed by clinical and/or radiologic examination. Results: The median follow-up was 8 years (range, 0.1-21 years). Lymphovascular invasion was present in 211 patients (17%). In univariate analysis, patients with LVI had a higher rate of RNF (3.32% vs. 1.15%; p = 0.02). In multivariate analysis, only tumor size, grade, and local failure were significant predictors of RNF (p = 0.049, 0.013, and 0.0001, respectively), whereas LVI did not show a significant relationship with RNF (hazard ratio = 2.07; 95% CI, 0.8-5.5; p = 0.143). The presence of LVI in the T2/3 population did not increase the risk of RNF over that for those with no LVI (p = 0.15). In addition, patients with Grade 3 tumors and positive LVI did not have a higher risk of RNF than those without LVI (p = 0.96). Conclusion: These results suggest that LVI can not be used as a sole indicator for regional nodal irradiation in breast cancer patients with zero to three positive lymph nodes treated with BCT.
Regional Nodal Involvement and Patterns of Spread Along In-Transit Pathways in Children With Rhabdomyosarcoma of the Extremity: A Report From the Children's Oncology Group;Rhabdomyosarcoma; Regional failure; In-transit nodes; Radiotherapy; Extremity
La, Trang H.; Wolden, Suzanne L.; Rodeberg, David A.; Hawkins, Douglas S.; Anderson, James R.; Donaldson, Sarah S.
Purpose: To evaluate the incidence and prognostic factors for regional failure, with attention to the in-transit pathways of spread, in children with nonmetastatic rhabdomyosarcoma of the extremity. Methods and Materials: The Intergroup rhabdomyosarcoma studies III, IV-Pilot, and IV enrolled 226 children with rhabdomyosarcoma of the extremity. Failure at the in-transit (epitrochlear/brachial and popliteal) and proximal (axillary/infraclavicular and inguinal/femoral) lymph nodes was evaluated. The median follow-up for the surviving patients was 10.4 years. Results: Of the 226 children, 55 (24%) had clinical or pathologic evidence of either in-transit and/or proximal lymph node involvement at diagnosis. The actuarial 5-year risk of regional failure was 12%. The prognostic factors for poor regional control were female gender and lymph node involvement at diagnosis. In the 116 patients with a distal extremity primary tumor, 5% had in-transit lymph node involvement at diagnosis. The estimated 5-year incidences of in-transit and proximal nodal failure was 12% and 8%, respectively. The in-transit failure rate was 0% for patients who underwent radiotherapy and/or underwent lymph node sampling of the in-transit nodal site but was 15% for those who did not (p = .07). However, the 5-year event-free survival rate did not differ between these two groups (64% vs. 55%, respectively, p = .47). Conclusion: The high incidence of regional involvement necessitates aggressive identification and treatment of regional lymph nodes in patients with rhabdomyosarcoma of the extremity. In patients with distal extremity tumors, in-transit failures were as common as failures in more proximal regional sites. Patients who underwent complete lymph node staging with appropriate radiotherapy to the in-transit nodal site, if indicated, were at a slightly lower risk of in-transit failure.
Nodal failure index approach to groundwater remediation design
Lee, J.; Reeves, H.W.; Dowding, C.H.
Computer simulations often are used to design and to optimize groundwater remediation systems. We present a new computationally efficient approach that calculates the reliability of remedial design at every location in a model domain with a single simulation. The estimated reliability and other model information are used to select a best remedial option for given site conditions, conceptual model, and available data. To evaluate design performance, we introduce the nodal failure index (NFI) to determine the number of nodal locations at which the probability of success is below the design requirement. The strength of the NFI approach is that selected areas of interest can be specified for analysis and the best remedial design determined for this target region. An example application of the NFI approach using a hypothetical model shows how the spatial distribution of reliability can be used for a decision support system in groundwater remediation design. ?? 2008 ASCE.
The impact of the number of excised axillary nodes and of the percentage of involved nodes on regional nodal failure in patients treated by breast-conserving surgery with or without regional irradiation
Fortin, Andre . E-mail: firstname.lastname@example.com; Dagnault, Anne; Blondeau, Lucie; Thi Trinh Thuc Vu; Larochelle, Marie
Purpose: After breast-conserving surgery, recommendations for regional nodal radiotherapy are usually based on the number of positive nodes. This number is dependent on the number of nodes removed during the axillary dissection. This study examines whether the percentage of positive nodes may help to select patients for regional radiotherapy. Methods and Materials: A retrospective study was conducted on 1,372 T1-T2 node-positive breast cancer patients treated at L'Hotel-Dieu de Quebec Hospital between 1972 and 1997. Results: Among the patients who did not receive regional radiotherapy, the percentage of involved nodes was significantly associated with axillary failure. Ten-year axillary control rates were 97% and 91% when the percentage of involved nodes was <50% and {>=}50%, respectively (p = 0.007). In addition, regional radiotherapy is always significantly associated with a decrease in overall regional failure (axillary and/or supraclavicular), regardless of the percentage of involved nodes. However, regional radiotherapy reduced the axillary failure rate (2% vs. 9%, p = 0.007) only when more than a specific percentage of nodes was involved ({>=}40% if N1-3 and {>=}50% if N>3 nodes). Conclusions: The percentage of involved nodes should be taken into consideration in selecting patients for regional radiotherapy. Irradiation of the axilla should be reserved for patients with a specific ratio: >40% involved nodes if N1-3 and {>=}50% involved nodes if N>3 nodes.
Combined-modality therapy for patients with regional nodal metastases from melanoma
Ballo, Matthew T. . E-mail: firstname.lastname@example.com; Ross, Merrick I.; Cormier, Janice N.; Myers, Jeffrey N.; Lee, Jeffrey E.; Gershenwald, Jeffrey E.; Hwu, Patrick; Zagars, Gunar K.
Purpose: To evaluate the outcome and patterns of failure for patients with nodal metastases from melanoma treated with combined-modality therapy. Methods and Materials: Between 1983 and 2003, 466 patients with nodal metastases from melanoma were managed with lymphadenectomy and radiation, with or without systemic therapy. Surgery was a therapeutic procedure for clinically apparent nodal disease in 434 patients (regionally advanced nodal disease). Adjuvant radiation was generally delivered with a hypofractionated regimen. Adjuvant systemic therapy was delivered to 154 patients. Results: With a median follow-up of 4.2 years, 252 patients relapsed and 203 patients died of progressive disease. The actuarial 5-year disease-specific, disease-free, and distant metastasis-free survival rates were 49%, 42%, and 44%, respectively. By multivariate analysis, increasing number of involved lymph nodes and primary ulceration were associated with an inferior 5-year actuarial disease-specific and distant metastasis-free survival. Also, the number of involved lymph nodes was associated with the development of brain metastases, whereas thickness was associated with lung metastases, and primary ulceration was associated with liver metastases. The actuarial 5-year regional (in-basin) control rate for all patients was 89%, and on multivariate analysis there were no patient or disease characteristics associated with inferior regional control. The risk of lymphedema was highest for those patients with groin lymph node metastases. Conclusions: Although regional nodal disease can be satisfactorily controlled with lymphadenectomy and radiation, the risk of distant metastases and melanoma death remains high. A management approach to these patients that accounts for the competing risks of distant metastases, regional failure, and long-term toxicity is needed.
Regional Stress Orientations and Slip Compatibility of Earthquake Focal Mechanism Nodal Planes in the New Madrid Seismic Zone
NASA Astrophysics Data System (ADS)
Hurd, O.; Zoback, M. D.
In this study we revisit the question of slip on faults in the New Madrid seismic zone in the context of the regional stress field. Specifically, we utilize newly available data to investigate whether fault slip is compatible with the regional stress field and laboratory-determined coefficients of friction (as originally argued by M.D. Zoback and M.L. Zoback, Science, 1981) or if there is evidence for either local sources of stress or anomalously low fault strength. Ten new, well-constrained earthquake focal plane mechanisms from the New Madrid seismic zone are available to update regional stress data and two earthquake focal plane mechanisms originally published in the 1970's have recently been revised. Utilizing these data, we demonstrate that the earthquakes occur on nodal planes which are optimally-oriented for shear failure in the current stress field assuming hydrostatic pore pressure in the brittle crust and coefficients of friction (μ) of about 0.6. The average SHmax orientation inferred from P-axes of the 12 focal mechanisms is N84E +/- 21°, which is consistent with the overall trend of SHmax in the region. In a manner similar to the study by M.L. Zoback (JGR, 1992), which utilized a slightly smaller (and in two cases, less reliable) set of focal mechanisms in this area, we use the orientation of the focal mechanism nodal planes combined with independent stress data to investigate the compatibility of slip on both nodal planes in the current stress field. First, the relative magnitudes of the three principal stresses are calculated from the nodal plane and stress orientations. Next, we utilize Mohr-Coulomb failure criterion to calculate the theoretically-optimal orientation of a fault plane for different coefficients of friction. Lastly, we calculate the difference in orientation between the theoretically-optimal planes and the focal mechanism nodal planes and identify the nodal plane with the smaller difference as the preferred nodal plane. For μ = 0
Successful catheter ablation of a slow AV-nodal pathway from the left posteroseptal region.
Wieczorek, M; Höltgen, R; Djajadisastra, I
We present the case of a 44 year old woman with recurrent episodes of supraventricular tachycardia due to AV-nodal reentry (AVNRT). She was refractory to conventional medical treatment and referred to our hospital with the view to catheter ablation of the slow AV-nodal pathway. AVNRT of the common type was easily induced performing stimulation from the high right atrium and proximal coronary sinus. Other forms of supraventricular tachycardia were definitely ruled out during further electrophysiologic study. Repetitive RF applications around the right posteroseptal region failed to cure the tachycardia which remained inducible with a typical jump in the AH interval. Extensive RF applications from posteroinferior to the midseptum including the area of the proximal coronary sinus and its os were ineffective as well.AVNRT was transiently but reproducibly eliminated while burns were applied to the high midseptum but AVNRT reoccured within 20 minutes. Finally after retrograde passage of the aortic valve with a 4 mm tip ablation catheter, RF was applied to the left postero to midseptal region. An accelerated junctional rhythm was immediately observed and AVNRT remained non-inducible from that time onwards. It is concluded that an atypical posterior extension of the AV node with predominant leftatrial course might be responsible for this unusual success of slow pathway elimination from left posteroseptal.
Role of Ultrasonography of Regional Nodal Basins in Staging Triple-Negative Breast Cancer and Implications For Local-Regional Treatment
Shaitelman, Simona F.; Tereffe, Welela; Dogan, Basak E.; Hess, Kenneth R.; Caudle, Abigail S.; Valero, Vicente; Stauder, Michael C.; Krishnamurthy, Savitri; Candelaria, Rosalind P.; Strom, Eric A.; Woodward, Wendy A.; Hunt, Kelly K.; Buchholz, Thomas A.; Whitman, Gary J.
Purpose: We sought to determine the rate at which regional nodal ultrasonography would increase the nodal disease stage in patients with triple-negative breast cancer (TNBC) beyond the clinical stage determined by physical examination and mammography alone, and significantly affect the treatments delivered to these patients. Methods and Materials: We retrospectively reviewed the charts of women with stages I to III TNBC who underwent physical examination, mammography, breast and regional nodal ultrasonography with needle biopsy of abnormal nodes, and definitive local-regional treatment at our institution between 2004 and 2011. The stages of these patients' disease with and without ultrasonography of the regional nodal basins were compared using the Pearson χ{sup 2} test. Definitive treatments of patients whose nodal disease was upstaged on the basis of ultrasonographic findings were compared to those of patients whose disease stage remained the same. Results: A total of 572 women met the study requirements. In 111 (19.4%) of these patients, regional nodal ultrasonography with needle biopsy resulted in an increase in disease stage from the original stage by physical examination and mammography alone. Significantly higher percentages of patients whose nodal disease was upstaged by ultrasonographic findings compared to that in patients whose disease was not upstaged underwent neoadjuvant systemic therapy (91.9% and 51.2%, respectively; P<.0001), axillary lymph node dissection (99.1% and 34.5%, respectively; P<.0001), and radiation to the regional nodal basins (88.2% and 29.1%, respectively; P<.0001). Conclusions: Regional nodal ultrasonography in TNBC frequently changes the initial clinical stage and plays an important role in treatment planning.
Comparison between 18F-Fluorodeoxyglucose Positron Emission Tomography and Sentinel Lymph Node Biopsy for Regional Lymph Nodal Staging in Patients with Melanoma: A Review of the Literature
Mirk, Paoletta; Treglia, Giorgio; Salsano, Marco; Basile, Pietro; Giordano, Alessandro; Bonomo, Lorenzo
Aim. to compare 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET) to sentinel lymph node biopsy (SLNB) for regional lymph nodal staging in patients with melanoma. Methods. We performed a literature review discussing original articles which compared FDG-PET to SLNB for regional lymph nodal staging in patients with melanoma. Results and Conclusions. There is consensus in the literature that FDG-PET cannot replace SLNB for regional lymph nodal staging in patients with melanoma. PMID:22242204
Inland waterway ports nodal attraction indices relevant in development strategies on regional level
NASA Astrophysics Data System (ADS)
Dinu, O.; Burciu, Ş.; Oprea, C.; Ilie, A.; Rosca, M.
Present paper aims to propose a set of ranking indices and related criteria, concerning mainly spatial analysis, for the inland waterway port, with special view on inland ports of Danube. Commonly, the attraction potential of a certain transport node is assessed by its spatial accessibility indices considering both spatial features of the location provided by the networks that connect into that node and its economic potential defining the level of traffic flows depending on the economic centers of its hinterland. Paper starts with a overview of the critical needs that are required for potential sites to become inland waterway ports and presents nodal functions that coexist at different levels, leading to a port hierarchy from the points of view of: capacity, connection to hinterland, traffic structure and volume. After a brief review of the key inland waterway port ranking criterion, a selection of nodal attraction measures is made. Particular considerations for the Danube inland port case follows proposed methodology concerning indices of performance for network scale and centrality. As expected, the shorter the distance from an inland port to the nearest access point the greater accessibility. Major differences in ranking, dependent on selected criterion, were registered.
Nodal Dependent Differential Localisation of Dishevelled-2 Demarcates Regions of Differing Cell Behaviour in the Visceral Endoderm
Trichas, Georgios; Wilkins, Vivienne; Clements, Melanie; Tada, Masazumi; Rodriguez, Tristan A.; Srinivas, Shankar
The anterior visceral endoderm (AVE), a signalling centre within the simple epithelium of the visceral endoderm (VE), is required for anterior-posterior axis specification in the mouse embryo. AVE cells migrate directionally within the VE, thereby properly positioning the future anterior of the embryo and orientating the primary body axis. AVE cells consistently come to an abrupt stop at the border between the anterior epiblast and extra-embryonic ectoderm, which represents an end-point to their proximal migration. Little is known about the underlying basis for this barrier and how surrounding cells in the VE respond to or influence AVE migration. We use high-resolution 3D reconstructions of protein localisation patterns and time-lapse microscopy to show that AVE cells move by exchanging neighbours within an intact epithelium. Cell movement and mixing is restricted to the VE overlying the epiblast, characterised by the enrichment of Dishevelled-2 (Dvl2) to the lateral plasma membrane, a hallmark of Planar Cell Polarity (PCP) signalling. AVE cells halt upon reaching the adjoining region of VE overlying the extra-embryonic ectoderm, which displays reduced neighbour exchange and in which Dvl2 is excluded specifically from the plasma membrane. Though a single continuous sheet, these two regions of VE show distinct patterns of F-actin localisation, in cortical rings and an apical shroud, respectively. We genetically perturb PCP signalling and show that this disrupts the localisation pattern of Dvl2 and F-actin and the normal migration of AVE cells. In Nodal null embryos, membrane localisation of Dvl2 is reduced, while in mutants for the Nodal inhibitor Lefty1, Dvl2 is ectopically membrane localised, establishing a role for Nodal in modulating PCP signalling. These results show that the limits of AVE migration are determined by regional differences in cell behaviour and protein localisation within an otherwise apparently uniform VE. In addition to coordinating global
Patterns of Failure for Rhabdomyosarcoma of the Perineal and Perianal Region
Casey, Dana L.; Wexler, Leonard H.; LaQuaglia, Michael P.; Meyers, Paul A.; Wolden, Suzanne L.
Purpose: To analyze prognostic factors and patterns of failure for rhabdomyosarcoma of the perineal and perianal region (PRMS), with an emphasis on radiation therapy for locoregional control. Methods and Materials: Detailed records of all 14 patients treated for PRMS at Memorial Sloan-Kettering Cancer Center between 1998 and 2012 were reviewed. The Kaplan-Meier method was used to assess the event-free survival (EFS) and overall survival (OS), and a competing-risks analysis was used to assess the cumulative incidence of local, regional, and distant failures. Results: Median age was 15.8 years (range, 1.1-31.9 years). High-risk features were identified: 9 of 14 patients (64%) had group 3 disease and 3 of 14 (21%) had group 4; 11 of 14 tumors (78%) were alveolar; 12 of 14 tumors (86%) were ≥5 cm; and 9 of 14 patients (64%) had involved lymph nodes (N1). Of those aged ≥10 years at diagnosis, 9 of 10 (90%) had alveolar histology, all had tumors ≥5 cm, and 8 of 10 (80%) presented with N1 disease. The rates of local, regional, and distant failure at 5 years were 17%, 31%, and 52%, respectively. Although 3 of the 4 patients with regional failure received nodal irradiation, only one of the nodal failures occurred in the radiation therapy field. The 5-year EFS was 33%, and OS was 39%. Age ≥10 years was associated with poor outcomes: EFS was 13% in patients aged ≥10 years, compared with 75% in those aged <10 years (P=.04); the OS was 13% in patients aged ≥10 years, compared with 100% in those aged <10 years (P=.04). Conclusions: Patients with PRMS, especially those aged ≥10 years, present with poor prognostic features and continue to have poor outcomes. Given the high incidence of regional node recurrence, we recommend prophylactic ilioinguinal lymph node irradiation for all patients aged ≥10 years. For children aged <10 years, nodal evaluation is essential to determine the role for lymph node irradiation.
Radiotherapy for Esthesioneuroblastoma: Is Elective Nodal Irradiation Warranted in the Multimodality Treatment Approach?
Noh, O Kyu; Lee, Sang-wook; Yoon, Sang Min; Kim, Sung Bae; Kim, Sang Yoon; Kim, Chang Jin; Jo, Kyung Ja; Choi, Eun Kyung; Song, Si Yeol; Kim, Jong Hoon; Ahn, Seung Do
Purpose: The role of elective nodal irradiation (ENI) in radiotherapy for esthesioneuroblastoma (ENB) has not been clearly defined. We analyzed treatment outcomes of patients with ENB and the frequency of cervical nodal failure in the absence of ENI. Methods and Materials: Between August 1996 and December 2007, we consulted with 19 patients with ENB regarding radiotherapy. Initial treatment consisted of surgery alone in 2 patients; surgery and postoperative radiotherapy in 4; surgery and adjuvant chemotherapy in 1; surgery, postoperative radiotherapy, and chemotherapy in 3; and chemotherapy followed by radiotherapy or concurrent chemoradiotherapy in 5. Five patients did not receive planned radiotherapy because of disease progression. Including 2 patients who received salvage radiotherapy, 14 patients were treated with radiotherapy. Elective nodal irradiation was performed in 4 patients with high-risk factors, including 3 with cervical lymph node metastasis at presentation. Results: Fourteen patients were analyzable, with a median follow-up of 27 months (range, 7-64 months). The overall 3-year survival rate was 73.4%. Local failure occurred in 3 patients (21.4%), regional cervical failure in 3 (21.4%), and distant failure in 2 (14.3%). No cervical nodal failure occurred in patients treated with combined systemic chemotherapy regardless of ENI. Three cervical failures occurred in the 4 patients treated with ENI or neck dissection (75%), none of whom received systemic chemotherapy. Conclusions: ENI during radiotherapy for ENB seems to play a limited role in preventing cervical nodal failure. Omitting ENI may be an option if patients are treated with a combination of radiotherapy and chemotherapy.
Selective Nodal Irradiation on Basis of {sup 18}FDG-PET Scans in Limited-Disease Small-Cell Lung Cancer: A Prospective Study
Loon, Judith van; De Ruysscher, Dirk; Wanders, Rinus; Boersma, Liesbeth; Simons, Jean; Oellers, Michel; Dingemans, Anne-Marie C.; Hochstenbag, Monique; Bootsma, Gerben; Geraedts, Wiel; Pitz, Cordula; Teule, Jaap; Rhami, Ali; Thimister, Willy; Snoep, Gabriel; Dehing-Oberije, Cary; Lambin, Philippe
Purpose: To evaluate the results of selective nodal irradiation on basis of {sup 18}F-deoxyglucose positron emission tomography (PET) scans in patients with limited-disease small-cell lung cancer (LD-SCLC) on isolated nodal failure. Methods and Materials: A prospective study was performed of 60 patients with LD-SCLC. Radiotherapy was given to a dose of 45 Gy in twice-daily fractions of 1.5 Gy, concurrent with carboplatin and etoposide chemotherapy. Only the primary tumor and the mediastinal lymph nodes involved on the pretreatment PET scan were irradiated. A chest computed tomography (CT) scan was performed 3 months after radiotherapy completion and every 6 months thereafter. Results: A difference was seen in the involved nodal stations between the pretreatment {sup 18}F-deoxyglucose PET scans and computed tomography scans in 30% of patients (95% confidence interval, 20-43%). Of the 60 patients, 39 (65%; 95% confidence interval [CI], 52-76%) developed a recurrence; 2 patients (3%, 95% CI, 1-11%) experienced isolated regional failure. The median actuarial overall survival was 19 months (95% CI, 17-21). The median actuarial progression-free survival was 14 months (95% CI, 12-16). 12% (95% CI, 6-22%) of patients experienced acute Grade 3 (Common Terminology Criteria for Adverse Events, version 3.0) esophagitis. Conclusion: PET-based selective nodal irradiation for LD-SCLC resulted in a low rate of isolated nodal failures (3%), with a low percentage of acute esophagitis. These findings are in contrast to those from our prospective study of CT-based selective nodal irradiation, which resulted in an unexpectedly high percentage of isolated nodal failures (11%). Because of the low rate of isolated nodal failures and toxicity, we believe that our data support the use of PET-based SNI for LD-SCLC.
Risk Factors for Regional Nodal Relapse in Breast Cancer Patients With One to Three Positive Axillary Nodes
Yates, Lucy; Kirby, Anna; Crichton, Siobhan; Gillett, Cheryl; Cane, Paul; Fentiman, Ian; Sawyer, Elinor
Purpose: In many centers, supraclavicular fossa radiotherapy (SCF RT) is not routinely offered to breast cancer patients with one to three positive lymph nodes. We aimed to identify a subgroup of these patients who are at high risk of supra or infraclavicular fossa relapse (SCFR) such that they can be offered SCFRT at the time of diagnosis to improve long term locoregional control. Methods and Materials: We performed a retrospective analysis of the pathological features of 1,065 cases of invasive breast cancer with one to three positive axillary lymph nodes. Patients underwent radical breast conserving surgery or mastectomy. A total of 45% of patients received adjuvant chest wall/breast RT. No patients received adjuvant SCFRT. The primary outcome was SCFR. Secondary outcomes were chest wall/breast recurrence, distant metastasis, all death, and breast-cancer specific death. Kaplan-Meier estimates were used to calculate actuarial event rates and survival functions compared using log-rank tests. Multivariate analyses (MVA) of factors associated with outcome were conducted using Cox proportional hazards models. Results: Median follow-up was 9.7 years. SCFR rate was 9.2%. Median time from primary diagnosis to SCFR was 3.4 years (range, 0.7-14.4 years). SCFR was associated with significantly lower 10-year survival (18% vs. 65%; p < 0.001). Higher grade and number of positive lymph nodes were the most significant predictors of SCFR on MVA (p < 0.001). 10 year SCFR rates were less than 1% in all patients with Grade 1 cancers compared with 30% in those having Grade 3 cancers with three positive lymph nodes. Additional factors associated with SCFR on univariate analysis but not on MVA included larger nodal deposits (p = 0.002) and proportion of positive nodes (p = 0.003). Conclusions: Breast cancer patients with one to three positive lymph nodes have a heterogenous risk of SCFR. Patients with two to three positive axillary nodes and/or high-grade disease may warrant
Three-Dimensional Conformal Radiation Therapy for Esophageal Squamous Cell Carcinoma: Is Elective Nodal Irradiation Necessary?
Zhao Kuaile; Ma Jinbo; Liu Guang; Wu Kailiang; Shi Xuehui; Jiang Guoliang
Purpose: To evaluate the local control, survival, and toxicity associated with three-dimensional conformal radiotherapy (3D-CRT) for squamous cell carcinoma (SCC) of the esophagus, to determine the appropriate target volumes, and to determine whether elective nodal irradiation is necessary in these patients. Methods and Materials: A prospective study of 3D-CRT was undertaken in patients with esophageal SCC without distant metastases. Patients received 68.4 Gy in 41 fractions over 44 days using late-course accelerated hyperfractionated 3D-CRT. Only the primary tumor and positive lymph nodes were irradiated. Isolated out-of-field regional nodal recurrence was defined as a recurrence in an initially uninvolved regional lymph node. Results: All 53 patients who made up the study population tolerated the irradiation well. No acute or late Grade 4 or 5 toxicity was observed. The median survival time was 30 months (95% confidence interval, 17.7-41.8). The overall survival rate at 1, 2, and 3 years was 77%, 56%, and 41%, respectively. The local control rate at 1, 2, and 3 years was 83%, 74%, and 62%, respectively. Thirty-nine of the 53 patients (74%) showed treatment failure. Seventeen of the 39 (44%) developed an in-field recurrence, 18 (46%) distant metastasis with or without regional failure, and 3 (8%) an isolated out-of-field nodal recurrence only. One patient died of disease in an unknown location. Conclusions: In patients treated with 3D-CRT for esophageal SCC, the omission of elective nodal irradiation was not associated with a significant amount of failure in lymph node regions not included in the planning target volume. Local failure and distant metastases remained the predominant problems.
An Empirical Approach to Logical Clustering of Software Failure Regions
that study was quite preliminary and local in its investigation. This thesis examines clustering from two other perspectives, taxonomical (type of...clustering was cross-examined across the perspectives. The results show that the studied failure regions have a strong tendency to form taxonornical...propagation of the fault (structural clustering). However, that study was quite preliminary and local in its investigation. This thesis examines clustering
NASA Astrophysics Data System (ADS)
Bzdušek, Tomáš; Wu, Quansheng; Rüegg, Andreas; Sigrist, Manfred; Soluyanov, Alexey A.
The band theory of solids is arguably the most successful theory of condensed-matter physics, providing a description of the electronic energy levels in various materials. Electronic wavefunctions obtained from the band theory enable a topological characterization of metals for which the electronic spectrum may host robust, topologically protected, fermionic quasiparticles. Many of these quasiparticles are analogues of the elementary particles of the Standard Model, but others do not have a counterpart in relativistic high-energy theories. A complete list of possible quasiparticles in solids is lacking, even in the non-interacting case. Here we describe the possible existence of a hitherto unrecognized type of fermionic excitation in metals. This excitation forms a nodal chain—a chain of connected loops in momentum space—along which conduction and valence bands touch. We prove that the nodal chain is topologically distinct from previously reported excitations. We discuss the symmetry requirements for the appearance of this excitation and predict that it is realized in an existing material, iridium tetrafluoride (IrF4), as well as in other compounds of this class of materials. Using IrF4 as an example, we provide a discussion of the topological surface states associated with the nodal chain. We argue that the presence of the nodal-chain fermions will result in anomalous magnetotransport properties, distinct from those of materials exhibiting previously known excitations.
New Anti-Nodal Monoclonal Antibodies Targeting the Nodal Pre-Helix Loop Involved in Cripto-1 Binding
Focà, Annalia; Sanguigno, Luca; Focà, Giuseppina; Strizzi, Luigi; Iannitti, Roberta; Palumbo, Rosanna; Hendrix, Mary J. C.; Leonardi, Antonio; Ruvo, Menotti; Sandomenico, Annamaria
Nodal is a potent embryonic morphogen belonging to the TGF-β superfamily. Typically, it also binds to the ALK4/ActRIIB receptor complex in the presence of the co-receptor Cripto-1. Nodal expression is physiologically restricted to embryonic tissues and human embryonic stem cells, is absent in normal cells but re-emerges in several human cancers, including melanoma, breast, and colon cancer. Our aim was to obtain mAbs able to recognize Nodal on a major CBR (Cripto-Binding-Region) site and to block the Cripto-1-mediated signalling. To achieve this, antibodies were raised against hNodal(44–67) and mAbs generated by the hybridoma technology. We have selected one mAb, named 3D1, which strongly associates with full-length rhNodal (KD 1.4 nM) and recognizes the endogenous protein in a panel of human melanoma cell lines by western blot and FACS analyses. 3D1 inhibits the Nodal-Cripto-1 binding and blocks Smad2/3 phosphorylation. Data suggest that inhibition of the Nodal-Cripto-1 axis is a valid therapeutic approach against melanoma and 3D1 is a promising and interesting agent for blocking Nodal-Cripto mediated tumor development. These findings increase the interest for Nodal as both a diagnostic and prognostic marker and as a potential new target for therapeutic intervention. PMID:26370966
Topological nodal line semimetals
NASA Astrophysics Data System (ADS)
Fang, Chen; Weng, Hongming; Dai, Xi; Fang, Zhong
We review the recent, mainly theoretical, progress in the study of topological nodal line semimetals in three dimensions. In these semimetals, the conduction and the valence bands cross each other along a one-dimensional curve in the three-dimensional Brillouin zone, and any perturbation that preserves a certain symmetry group (generated by either spatial symmetries or time-reversal symmetry) cannot remove this crossing line and open a full direct gap between the two bands. The nodal line(s) is hence topologically protected by the symmetry group, and can be associated with a topological invariant. In this review, (i) we enumerate the symmetry groups that may protect a topological nodal line; (ii) we write down the explicit form of the topological invariant for each of these symmetry groups in terms of the wave functions on the Fermi surface, establishing a topological classification; (iii) for certain classes, we review the proposals for the realization of these semimetals in real materials; (iv) we discuss different scenarios that when the protecting symmetry is broken, how a topological nodal line semimetal becomes Weyl semimetals, Dirac semimetals, and other topological phases; and (v) we discuss the possible physical effects accessible to experimental probes in these materials. Project partially supported by the National Key Research and Development Program of China (Grant Nos. 2016YFA0302400 and 2016YFA0300604), partially by the National Natural Science Foundation of China (Grant Nos. 11274359 and 11422428), the National Basic Research Program of China (Grant No. 2013CB921700), and the "Strategic Priority Research Program (B)" of the Chinese Academy of Sciences (Grant No. XDB07020100).
Reduced Regional Brain Cortical Thickness in Patients with Heart Failure
Kumar, Rajesh; Yadav, Santosh K.; Palomares, Jose A.; Park, Bumhee; Joshi, Shantanu H.; Ogren, Jennifer A.; Macey, Paul M.; Fonarow, Gregg C.; Harper, Ronald M.; Woo, Mary A.
Aims Autonomic, cognitive, and neuropsychologic deficits appear in heart failure (HF) subjects, and these compromised functions depend on cerebral cortex integrity in addition to that of subcortical and brainstem sites. Impaired autoregulation, low cardiac output, sleep-disordered-breathing, hypertension, and diabetic conditions in HF offer considerable potential to affect cortical areas by loss of neurons and glia, which would be expressed as reduced cortical thicknesses. However, except for gross descriptions of cortical volume loss/injury, regional cortical thickness integrity in HF is unknown. Our goal was to assess regional cortical thicknesses across the brain in HF, compared to control subjects. Methods and Results We examined localized cortical thicknesses in 35 HF and 61 control subjects with high-resolution T1-weighted images (3.0-Tesla MRI) using FreeSurfer software, and assessed group differences with analysis-of-covariance (covariates; age, gender; p<0.05; FDR). Significantly-reduced cortical thicknesses appeared in HF over controls in multiple areas, including the frontal, parietal, temporal, and occipital lobes, more markedly on the left side, within areas that control autonomic, cognitive, affective, language, and visual functions. Conclusion Heart failure subjects show reduced regional cortical thicknesses in sites that control autonomic, cognitive, affective, language, and visual functions that are deficient in the condition. The findings suggest chronic tissue alterations, with regional changes reflecting loss of neurons and glia, and presumably are related to earlier-described axonal changes. The pathological mechanisms contributing to reduced cortical thicknesses likely include hypoxia/ischemia, accompanying impaired cerebral perfusion from reduced cardiac output and sleep-disordered-breathing and other comorbidities in HF. PMID:25962164
Temporal Nodal Regression and Regional Control After Primary Radiation Therapy for N2-N3 Head-and-Neck Cancer Stratified by HPV Status
Huang, Shao Hui; O'Sullivan, Brian; Ringash, Jolie; Hope, Andrew; Gilbert, Ralph; Irish, Jonathan; Perez-Ordonez, Bayardo; Weinreb, Ilan; Waldron, John
Purpose: To compare the temporal lymph node (LN) regression and regional control (RC) after primary chemoradiation therapy/radiation therapy in human papillomavirus-related [HPV(+)] versus human papillomavirus-unrelated [HPV(−)] head-and-neck cancer (HNC). Methods and Materials: All cases of N2-N3 HNC treated with radiation therapy/chemoradiation therapy between 2003 and 2009 were reviewed. Human papillomavirus status was ascertained by p16 staining on all available oropharyngeal cancers. Larynx/hypopharynx cancers were considered HPV(−). Initial radiologic complete nodal response (CR) (≤1.0 cm 8-12 weeks after treatment), ultimate LN resolution, and RC were compared between HPV(+) and HPV(−) HNC. Multivariate analysis identified outcome predictors. Results: A total of 257 HPV(+) and 236 HPV(−) HNCs were identified. The initial LN size was larger (mean, 2.9 cm vs 2.5 cm; P<.01) with a higher proportion of cystic LNs (38% vs 6%, P<.01) in HPV(+) versus HPV(−) HNC. CR was achieved is 125 HPV(+) HNCs (49%) and 129 HPV(−) HNCs (55%) (P=.18). The mean post treatment largest LN was 36% of the original size in the HPV(+) group and 41% in the HPV(−) group (P<.01). The actuarial LN resolution was similar in the HPV(+) and HPV(−) groups at 12 weeks (42% and 43%, respectively), but it was higher in the HPV(+) group than in the HPV(−) group at 36 weeks (90% vs 77%, P<.01). The median follow-up period was 3.6 years. The 3-year RC rate was higher in the HPV(−) CR cases versus non-CR cases (92% vs 63%, P<.01) but was not different in the HPV(+) CR cases versus non-CR cases (98% vs 92%, P=.14). On multivariate analysis, HPV(+) status predicted ultimate LN resolution (odds ratio, 1.4 [95% confidence interval, 1.1-1.7]; P<.01) and RC (hazard ratio, 0.3 [95% confidence interval 0.2-0.6]; P<.01). Conclusions: HPV(+) LNs involute more quickly than HPV(−) LNs but undergo a more prolonged process to eventual CR beyond the time of initial assessment at 8 to 12
Results of a Phase 2 Study Examining the Effects of Omitting Elective Neck Irradiation to Nodal Levels IV and V{sub b} in Patients With N{sub 0-1} Nasopharyngeal Carcinoma
Chen, Jian-zhou; Le, Quynh-Thu; Han, Fei; Lu, Li-Xia; Huang, Shao-Min; Lin, Cheng-Guang; Deng, Xiao-Wu; Cui, Nian-Ji; Zhao, Chong
Purpose: To evaluate the patterns of nodal failure and toxicity in clinically negative necks of N{sub 0-1} nasopharyngeal carcinoma (NPC) patients who were treated with intensity modulated radiation therapy (IMRT) but did not receive elective neck irradiation (ENI) to level IV and V{sub b} nodes. Methods and Materials: We conducted a phase 2 prospective study in N{sub 0-1} NPC patients treated with IMRT. ENI included the retropharyngeal nodes and levels II to V{sub a} but omitted levels IV and V{sub b} in clinically negative necks. Patterns of nodal failure, regional control (RC), and late toxicity were evaluated. Results: Between 2001 and 2008, a total of 212 patients (128 N{sub 0} and 84 N{sub 1}) were enrolled in the study. Seven patients (4 in-field and 3 out-of-field) developed nodal failure. One patient (0.5%) developed nodal failure at level V{sub b}, but no patients developed nodal failure at level IV. The 5-year RC rates of the entire group, N{sub 0} patients and N{sub 1} patients were 95.6%, 98.2%, and 91.3%, respectively. Fifteen patients (7.1%) developed distant metastases. The 5-year distant failure-free survival (DFFS) and overall survival (OS) rates were 91.4% and 89.8%, respectively. The rates of grade 2 or greater skin dystrophy, subcutaneous fibrosis and xerostomia were 6.2%, 16.6%, and 17.9%, respectively. Conclusions: The rate of out-of-field nodal failure when omitting ENI to levels IV and V{sub b} in clinically negative necks of patients with N{sub 0-1} NPC was extremely low; therefore, a further phase 3 study is warranted.
Study on Flexible Pavement Failures in Soft Soil Tropical Regions
NASA Astrophysics Data System (ADS)
Jayakumar, M.; Chee Soon, Lee
Road network system experienced rapid upgrowth since ages ago and it started developing in Malaysia during the colonization of British due to its significant impacts in transportation field. Flexible pavement, the major road network in Malaysia, has been deteriorating by various types of distresses which cause descending serviceability of the pavement structure. This paper discusses the pavement condition assessment carried out in Sarawak and Sabah, Malaysia to have design solutions for flexible pavement failures. Field tests were conducted to examine the subgrade strength of existing roads in Sarawak at various failure locations, to assess the impact of subgrade strength on pavement failures. Research outcomes from field condition assessment and subgrade testing showed that the critical causes of pavement failures are inadequate design and maintenance of drainage system and shoulder cross fall, along with inadequate pavement thickness provided by may be assuming the conservative value of soil strength at optimum moisture content, whereas the exiting and expected subgrade strengths at equilibrium moisture content are far below. Our further research shows that stabilized existing recycled asphalt and base materials to use as a sub-base along with bitumen stabilized open graded base in the pavement composition may be a viable solution for pavement failures.
Cripto recruits Furin and PACE4 and controls Nodal trafficking during proteolytic maturation.
Blanchet, Marie-Hélène; Le Good, J Ann; Mesnard, Daniel; Oorschot, Viola; Baflast, Stéphane; Minchiotti, Gabriella; Klumperman, Judith; Constam, Daniel B
The glycosylphosphatidylinositol (GPI)-anchored proteoglycan Cripto binds Nodal and its type I receptor Alk4 to activate Smad2,3 transcription factors, but a role during Nodal precursor processing has not been described. We show that Cripto also binds the proprotein convertases Furin and PACE4 and localizes Nodal processing at the cell surface. When coexpressed as in early embryonic cells, Cripto and uncleaved Nodal already associated during secretion, and a Cripto-interacting region in the Nodal propeptide potentiated the effect of proteolytic maturation on Nodal signalling. Disruption of the trans-Golgi network (TGN) by brefeldin A blocked secretion, but export of Cripto and Nodal to the cell surface was not inhibited, indicating that Nodal is exposed to extracellular convertases before entering the TGN/endosomal system. Density fractionation and antibody uptake experiments showed that Cripto guides the Nodal precursor in detergent-resistant membranes to endocytic microdomains marked by GFP-Flotillin. We conclude that Nodal processing and endocytosis are coupled in signal-receiving cells.
Evaluation of the use of nodal methods for MTR neutronic analysis
Reitsma, F.; Mueller, E.Z.
Although modern nodal methods are used extensively in the nuclear power industry, their use for research reactor analysis has been very limited. The suitability of nodal methods for material testing reactor analysis is investigated with the emphasis on the modelling of the core region (fuel assemblies). The nodal approach`s performance is compared with that of the traditional finite-difference fine mesh approach. The advantages of using nodal methods coupled with integrated cross section generation systems are highlighted, especially with respect to data preparation, simplicity of use and the possibility of performing a great variety of reactor calculations subject to strict time limitations such as are required for the RERTR program.
Distant nodal metastasis: is it always an unresectable disease?
Celotti, Andrea; Molfino, Sarah; Baggi, Paolo; Tarasconi, Antonio; Baronio, Gianluca; Arru, Luca; Gheza, Federico; Tiberio, Guido; Portolani, Nazario
This article aims at analyzing the published literature concerning the treatment of patients with gastric cancer and distant nodal metastases, actually considered metastatic disease. A systematic search was undertaken using Medline, Embase, Cochrane and Web-of-Science libraries. No specific restriction on year of publication was used; preference was given to English papers. Both clinical series and literature reviews were selected. Only 11 papers address the issue of surgery for nodal basins outside the D2 dissection area. From these papers, in selected cases extended surgery may prove useful in prolonging survival, when a comprehensive therapeutic pathway including chemotherapy is scheduled. In conclusion, in presence of nodal metastases outside the loco-regional nodes, surgery may be considered for metastatic nodes in stations 13 and 16, in selected cases. PMID:28217751
The structural robustness of geographical networks against regional failure and their pre-optimization
NASA Astrophysics Data System (ADS)
Li, Yixiao; Zhang, Lin; Huang, Chaogeng; Shen, Bin
Failures of real-world infrastructure networks due to natural disasters often originate in a certain region, but this feature has seldom been considered in theoretical models. In this article, we introduce a possible failure pattern of geographical networks-"regional failure"-by which nodes and edges within a region malfunction. Based on a previous spatial network model (Louf et al., 2013), we study the robustness of geographical networks against regional failure, which is measured by the fraction of nodes that remain in the largest connected component, via simulations. A small-area failure results in a large reduction of their robustness measure. Furthermore, we investigate two pre-deployed mechanisms to enhance their robustness: One is to extend the cost-benefit growth mechanism of the original network model by adding more than one link in a growth step, and the other is to strengthen the interconnection of hubs in generated networks. We measure the robustness-enhancing effects of both mechanisms on the basis of their costs, i.e., the amount of excessive links and the induced geographical length. The latter mechanism is better than the former one if a normal level of costs is considered. When costs exceed a certain level, the former has an advantage. Because the costs of excessive links affect the investment decision of real-world infrastructure networks, it is practical to enhance their robustness by adding more links between hubs. These results might help design robust geographical networks economically.
Magnetic graphene-based nanotheranostic agent for dual-modality mapping guided photothermal therapy in regional lymph nodal metastasis of pancreatic cancer.
Wang, Sheng; Zhang, Qin; Luo, Xian F; Li, Ji; He, Hang; Yang, Feng; Di, Yang; Jin, Chen; Jiang, Xin G; Shen, Shun; Fu, De L
Although regional lymph nodes (RLN) dissection remains the only way to cure pancreatic cancer metastasis, it is unavoidably associated with sizable trauma, multiple complications, and low surgical resection rates. Thus, exploring a treatment approach for the ablation of drug-resistant pancreatic cancer is always of great concern. Moreover, reoperative and intraoperative mapping of RLN is also important during treatment, because only a few lymph nodes can be detected by the naked eye. In our study, graphene oxides modified with iron oxide nanoparticles (GO-IONP) as a nanotheranostic agent is firstly developed to diagnose and treat RLN metastasis of pancreatic cancer. The approach was designed based on clinical practice, the GO-IONP agent directly injected into the tumor was transported to RLN via lymphatic vessels. Compared to commercial carbon nanoparticles currently used in the clinic operation, the GO-IONP showed powerful ability of dual-modality mapping of regional lymphatic system by magnetic resonance imaging (MRI), as well as dark color of the agent providing valuable information that was instrumental for surgeon in making the preoperative plan before operation and intraoperatively distinguish RLN from surrounding tissue. Under the guidance of dual-modality mapping, we further demonstrated that metastatic lymph nodes including abdominal nodes could be effectively ablated by near-infrared (NIR) irradiation with an incision operation. The lower systematic toxicity of GO-IONP and satisfying safety of photothermal therapy (PTT) to neighbor tissues have also been clearly illustrated in our animal experiments. Using GO-IONP as a nanotheranostic agent presents an approach for mapping and photothermal ablation of RLN, the later may serve as an alternative to lymph node dissection by invasive surgery.
Vulnerability and adaptation of urban dwellers in slope failure threats--a preliminary observation for the Klang Valley Region.
Thanapackiam, P; Salleh, Khairulmaini Osman; Ghaffar, Fauza Ab
This paper discusses the outcome of a research that examines the relationships between vulnerability and adaptation of urban dwellers to the slope failure threat in the Klang Valley Region. Intense urban landuse expansions in the Klang Valley Region have increased urban dwellers vulnerability to slope failures in recent years. The Klang Valley Region was chosen as the study area due to the increasing intensities and frequencies of slope failures threat. This paper examines urban dwellers vulnerability based on their (1) population and demographics characteristics, (2) the state of physical structures of dwellings and (3) the situation of the immediate environment threatened by slope failures. The locations of slope failure incidents were identified, mapped and examined followed with a detailed field study to identified areas. The results identified significant relationships between vulnerability indicators and slope failures in the Klang Valley Region. The findings of the study are envisaged to give valuable insights on addressing the threat of slope failures in the Klang Valley Region.
A prospective audit of regional anaesthesia failure in 5080 Caesarean sections.
Kinsella, S M
Anaesthesia for Caesarean section was audited over a 5 year period: 5080 cases were performed using spinal 63%, epidural top-up 26%, combined spinal-epidural 5% and primary general anaesthesia 5%. The rate of general anaesthesia conversion of regional anaesthesia was 0.8% for elective and 4.9% for emergency Caesarean section compared to Royal College of Anaesthetists targets of 1% and 3%. The rate of conversion of regional to general anaesthesia in category 1 Caesarean section was 20%. A total of 8% of women had general anaesthesia when both primary general and conversion of regional anaesthesia were combined. The rate of failure to achieve a pain-free operation was 6% with spinals, 24% with epidural top-up and 18% with combined spinal-epidural. Besides the type of anaesthesia and operative urgency, other factors associated with pre-operative failure of regional anaesthesia included body mass index, no previous Caesareans, and indication for Caesarean of acute fetal distress or maternal medical condition. Inadequacy of pre-operative anaesthetic block and duration of surgery were important risk factors for intra-operative failure. For spinal anaesthesia, use of a spinal opioid was associated with less pre-operative failure. For epidural top-up anaesthesia, lower epidural top-up volume was associated with less pre-operative failure, and use of adrenaline was associated with both less pre-operative and intra-operative failure. The rate of serious adverse incidents was 1 : 126 with general anaesthesia and 1 : 501 with regional anaesthesia.
Intensity-Modulated Radiation Therapy for the Treatment of Squamous Cell Anal Cancer With Para-aortic Nodal Involvement
Hodges, Joseph C.; Das, Prajnan; Eng, Cathy; Reish, Andrew G.; Beddar, A. Sam; Delclos, Marc E.; Krishnan, Sunil; Crane, Christopher H.
Purpose: To determine the rates of toxicity, locoregional control, distant control, and survival in anal cancer patients with para-aortic nodal involvement, treated with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy at a single institution. Methods and Materials: Between 2001 and 2007, 6 patients with squamous cell anal cancer and para-aortic nodal involvement were treated with IMRT and concurrent infusional 5-fluorouracil and cisplatin. The primary tumor was treated with a median dose of 57.5 Gy (range, 54-60 Gy), involved para-aortic, pelvic, and inguinal lymph nodes were treated with a median dose of 55 Gy (range, 50.5-55 Gy), and noninvolved nodal regions were treated with a median dose of 45 Gy (range, 43.5-45 Gy). Results: After a median follow-up of 25 months, none of the patients had a recurrence at the primary tumor, pelvic/inguinal nodes, or para-aortic nodes, whereas 2 patients developed distant metastases to the liver. Four of the 6 patients are alive. The 3-year actuarial locoregional control, distant control, and overall survival rates were 100%, 56%, and 63%, respectively. Four of the 6 patients developed Grade 3 acute gastrointestinal toxicity during chemoradiation. Conclusions: Intensity-modulated radiotherapy and concurrent chemotherapy could potentially serve as definitive therapy in anal cancer patients with para-aortic nodal involvement. Adjuvant chemotherapy may be indicated in these patients, as demonstrated by the distant failure rates. These patients need to be followed carefully because of the potential for treatment-related toxicities.
Heterogeneous treatment in the variational nodal method
Fanning, T.H.; Palmiotti, G.
The variational nodal transport method is reduced to its diffusion form and generalized for the treatment of heterogeneous nodes while maintaining nodal balances. Adapting variational methods to heterogeneous nodes requires the ability to integrate over a node with discontinuous cross sections. In this work, integrals are evaluated using composite gaussian quadrature rules, which permit accurate integration while minimizing computing time. Allowing structure within a nodal solution scheme avoids some of the necessity of cross section homogenization, and more accurately defines the intra-nodal flux shape. Ideally, any desired heterogeneity can be constructed within the node; but in reality, the finite set of basis functions limits the practical resolution to which fine detail can be defined within the node. Preliminary comparison tests show that the heterogeneous variational nodal method provides satisfactory results even if some improvements are needed for very difficult, configurations.
Molecular cytogenetic analysis of Xq critical regions in premature ovarian failure
Background One of the frequent reasons for unsuccessful conception is premature ovarian failure/primary ovarian insufficiency (POF/POI) that is defined as the loss of functional follicles below the age of 40 years. Among the genetic causes the most common one involves the X chromosome, as in Turner syndrome, partial X deletion and X-autosome translocations. Here we report a case of a 27-year-old female patient referred to genetic counselling because of premature ovarian failure. The aim of this case study to perform molecular genetic and cytogenetic analyses in order to identify the exact genetic background of the pathogenic phenotype. Results For premature ovarian failure disease diagnostics we performed the Fragile mental retardation 1 gene analysis using Southern blot technique and Repeat Primed PCR in order to identify the relationship between the Fragile mental retardation 1 gene premutation status and the premature ovarion failure disease. At this early onset, the premature ovarian failure affected patient we detected one normal allele of Fragile mental retardation 1 gene and we couldn't verify the methylated allele, therefore we performed the cytogenetic analyses using G-banding and fluorescent in situ hybridization methods and a high resolution molecular cytogenetic method, the array comparative genomic hybridization technique. For this patient applying the G-banding, we identified a large deletion on the X chromosome at the critical region (ChrX q21.31-q28) which is associated with the premature ovarian failure phenotype. In order to detect the exact breakpoints, we used a special cytogenetic array ISCA plus CGH array and we verified a 67.355 Mb size loss at the critical region which include total 795 genes. Conclusions We conclude for this case study that the karyotyping is definitely helpful in the evaluation of premature ovarian failure patients, to identify the non submicroscopic chromosomal rearrangement, and using the array CGH technique we can
Radial nodalization effects on BWR (boiling water reactor) stability calculations
March-Leuba, J.
Computer simulations have shown that stability calculations in boiling water reactors (BWRs) are very sensitive to a number of input parameters and modeling assumptions. In particular, the number of thermohydraulic regions (i.e., channels) used in the calculation can affect the results of decay ratio calculations by as much as 30%. This paper presents the background theory behind the observed effects of radial nodalization in BWR stability calculations. The theory of how a radial power distribution can be simulated in time or frequency domain codes by using representative'' regions is developed. The approximations involved in this method of solution are reviewed, and some examples of the effect of radial nodalization are presented based on LAPUR code solutions. 2 refs., 4 figs., 2 tabs.
Characterization of treatment failure in HIV positive patients in the Colombian Caribbean region
De La Hoz, Juan Manuel; Bolaño, Laura; Cárdenas, Oriana; González, Robertulio; Sabbag, José; Palacio, Lucy; Alonso, Luz Marina; San-Juan-Vergara, Homero
Background: Treatment failure (TF) in patients receiving antiretroviral therapy against human immunodeficiency virus (HIV) is always a concern. Objective: To examine the correlates associated with TF in patients living in the Colombian Caribbean city of Barranquilla, an aspect that was poorly studied in this region. Methods: Treatment failure was evaluated in a cross-sectional study from virological, immunological and clinical standpoints. Results: It was established that 29.5% of patients under highly active antiretroviral therapy (ART) could be considered in TF. Among those, virological failure was most frequent (20.9%), followed by immunological- (14.0%) and clinical failure (4.7%). In patients showing lack of adherence to the treatment, the likelihood of suffering from TF and virogical failure were respectively increased by 6.67-fold and 12.19-fold, compared with patients showing good adherence. Although there was no statistically significant association, TF tended to be more frequent in young adults, in patients with low income and, low level of education. When ART regimens were compared, there was no apparent difference in TF between regimens based on non-nucleoside reverse transcriptase inhibitors and those based on protease inhibitors. This is very important in the context of recent ART strategies, such as early-initiated ART, aimed at achieving long-term infection control. Conclusions: Is confirmed the importance of treatment adherence to avoid TF and further highlights the importance of educating HIV-infected patients in all parts of the world, especially those individuals with a lower socio-economic status. PMID:25767304
Optical conductivity of nodal metals
Homes, C. C.; Tu, J. J.; Li, J.; Gu, G. D.; Akrap, A.
Fermi liquid theory is remarkably successful in describing the transport and optical properties of metals; at frequencies higher than the scattering rate, the optical conductivity adopts the well-known power law behavior σ1(ω) ∝ ω−2. We have observed an unusual non-Fermi liquid response σ1(ω) ∝ ω−1±0.2 in the ground states of several cuprate and iron-based materials which undergo electronic or magnetic phase transitions resulting in dramatically reduced or nodal Fermi surfaces. The identification of an inverse (or fractional) power-law behavior in the residual optical conductivity now permits the removal of this contribution, revealing the direct transitions across the gap and allowing the nature of the electron-boson coupling to be probed. The non-Fermi liquid behavior in these systems may be the result of a common Fermi surface topology of Dirac cone-like features in the electronic dispersion. PMID:24336241
Distributions of Nodal Prices in PJM Market
NASA Astrophysics Data System (ADS)
Kunio, Matsumoto; Yoshio, Ichida; Michiko, Makino; Hiroaki, Tanaka
As the deregulation of electric business proceeds, it is important to analyze the distributions of prices in the power market. In this paper, we analyze the nodal prices of the PJM market, which is representative of power markets in the US. First, we verify Weibull's property of the distribution of nodal prices. Then we verify Poisson's property of the interval of loss process.
Nodal network generator for CAVE3
NASA Technical Reports Server (NTRS)
Palmieri, J. V.; Rathjen, K. A.
A new extension of CAVE3 code was developed that automates the creation of a finite difference math model in digital form ready for input to the CAVE3 code. The new software, Nodal Network Generator, is broken into two segments. One segment generates the model geometry using a Tektronix Tablet Digitizer and the other generates the actual finite difference model and allows for graphic verification using Tektronix 4014 Graphic Scope. Use of the Nodal Network Generator is described.
Time-Dependent Regional Myocardial Strains in Patients with Heart Failure with a Preserved Ejection Fraction
Smith, Shane P.; Secomb, Timothy W.; Hong, Brian D.; Moulton, Michael J.
Objectives. To better understand the etiology of HFpEF in a controlled human population, regional time-varying strains were computed using echocardiography speckle tracking in patients with heart failure with a preserved ejection fraction and normal subjects. Methods. Eleven normal volunteers and ten patients with echo-graded diastolic dysfunction and symptoms of heart failure were imaged with echocardiography and longitudinal, circumferential, and rotational strains were determined using speckle-tracking. Diastolic strain rate was also determined. Patient demographics and echo-derived flows, volumes, and pressures were recorded. Results. Peak longitudinal and circumferential strain was globally reduced in patients (p < 0.001), when compared to controls. The patients attained peak longitudinal and circumferential strain at a consistently later point in systole than controls. Rotational strains were not different in most LV regions. Early diastolic strain rate was significantly reduced in the patients (p < 0.001). LV mass and wall thickness were significantly increased in the patients; however ejection fraction was preserved and stroke volume was diminished (p < 0.001). Conclusions. This study shows that patients with HFpEF have reduced early diastolic strain rate and reduced peak strain that is regionally homogeneous and that they also utilize a longer fraction of systole to achieve peak axial strains. PMID:27042673
Freedom From Local and Regional Failure of Contralateral Neck With Ipsilateral Neck Radiotherapy for Node-Positive Tonsil Cancer: Results of a Prospective Management Approach
Rusthoven, Kyle E. Raben, David; Schneider, Charles; Witt, Robert; Sammons, Sarah; Raben, Adam
Purpose: To review the outcomes of a prospective management approach using ipsilateral neck radiotherapy in the treatment of node-positive squamous cell carcinoma of the tonsil with a well-lateralized primary lesion. Methods and Materials: Between August 2003 and June 2007, 20 patients who presented with squamous cell carcinoma of the tonsil, without involvement of the base of the tongue or midline soft palate, and with Stage N1-N2b disease were prospectively treated with radiotherapy to the primary site and ipsilateral neck. In addition, 18 patients received concurrent chemotherapy. The actuarial freedom from contralateral nodal and in-field progression was determined. Acute and late toxicity were prospectively evaluated using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 3, and Radiation Therapy Oncology Group criteria. Results: The nodal disease was Stage N1 in 4 patients, N2a in 3 patients, and N2b in 13 patients. At a median follow-up 19 months (range, 12-40), no in-field or contralateral nodal recurrences had been observed. The 2-year freedom from distant metastasis rate was 87.4%. The actuarial 2-year disease-free and overall survival rates were both 79.5%. Late Radiation Therapy Oncology Group grade 2 xerostomia occurred in 1 patient (5%). No late Grade 3 or greater toxicity was observed. No patient was feeding tube dependent at their last follow-up visit. Conclusion: In carefully selected patients with node-positive, lateralized tonsillar cancer, treatment of the ipsilateral neck and primary site does not appear to increase the risk of contralateral nodal failure and reduces late morbidity compared with historical controls. Although the outcomes with ipsilateral radiotherapy in the present series were promising, these findings require longer follow-up and validation in a larger patient cohort.
New role of biomarkers: mid-regional pro-adrenomedullin, the biomarker of organ failure
Valenzuela-Méndez, Blanca; Rodríguez-Gutiérrez, Juan Francisco; Estella-García, Ángel; González-García, María Ángela
Mid-regional pro-adrenomedullin (MR-proADM) has a good biomarker profile: its half-life is several hours, and its plasma concentrations can be determined in clinical practice, it is essentially irrelevant, but proportionally represents the levels and activity of adrenomedullin (ADM). ADM synthesis is widely distributed in tissues, including bone, adrenal cortex, kidney, lung, blood vessels and heart. Its fundamental biological effects include vasodilator, positive inotropic, diuretic, natriuretic and bronchodilator. It has been described high levels in septic patients, interacting directly with the relaxation of vascular tone, triggering hypotension of these patients. It is also found high levels in other diseases such as hypertension, heart failure, respiratory failure, renal failure, cirrhosis and cancer. MR-proADM has been identified as a prognostic marker, stratifying the mortality risk in patients with sepsis in emergency department (ED) and ICU. Evolutionary MR-proADM levels and clearance marker to the 2nd–5th days of admission help to determine the poor performance and the risk of mortality in patients with severe sepsis admitted to the ICU. The MR-proADM levels are more effective than procalcitonin (PCT) and C-reactive protein (CRP) levels to determine an unfavorable outcome and the risk of mortality in patients with sepsis admitted to the ICU. It has also proved useful in patients diagnosed with organ dysfunction of infectious etiology. MR-proADM levels are independent of the germ conversely it is related to the magnitude of organ failure and therefore severity. We consider advisable incorporating the MR-proADM the panel of biomarkers necessary for the diagnosis and treatment of critically ill patients admitted to the ICU with severe sepsis. The combined PCT and MR-proADM levels could represent a valid tool in the clinical practice to timely identify patients with bacterial infections and guide the diagnosis and treatment of sepsis and septic shock. PMID
Topological Phase Transitions in Line-nodal Superconductors
NASA Astrophysics Data System (ADS)
Cho, Gil Young; Han, Sangeun; Moon, Eun-Gook
Fathoming interplay between symmetry and topology of many-electron wave-functions deepens our understanding in quantum nature of many particle systems. Topology often protects zero-energy excitation, and in a certain class, symmetry is intrinsically tied to the topological protection. Namely, unless symmetry is broken, topological nature is intact. We study one specific case of such class, symmetry-protected line-nodal superconductors in three spatial dimensions (3d). Mismatch between phase spaces of order parameter fluctuation and line-nodal fermion excitation induces an exotic universality class in a drastic contrast to one of the conventional ϕ4 theory in 3d. Hyper-scaling violation and relativistic dynamic scaling with unusually large quantum critical region are main characteristics, and their implication in experiments is discussed. For example, continuous phase transition out of line-nodal superconductors has a linear phase boundary in a temperature-tuning parameter phase-diagram. This work was supported by the Brain Korea 21 PLUS Project of Korea Government and KAIST start-up funding.
Nodal equivalence theory for hexagonal geometry, thermal reactor analysis
Zika, M.; Downar, T. )
An important aspect of advanced nodal methods is the determination of equivalent few-group parameters for the relatively large homogenized regions used in the nodal flux solution. The theoretical foundation for light water reactor (LWR) assembly homogenization methods has been clearly established, and during the last several years, its successes have secured its position in the stable of dependable LWR analysis methods. Groupwise discontinuity factors that correct for assembly homogenization errors are routinely generated along with the group constants during lattice physics analysis. During the last several years, there has been interest in applying equivalence theory to other reactor types and other geometries. A notable effort has been the work at Argonne National Laboratory to incorporate nodal equivalence theory (NET) for hexagonal lattices into the nodal diffusion option of the DIF3D code. This work was originally intended to improve the neutronics methods used for the analysis of the Experimental Breeder Reactor II (EBR-II), and Ref. 4 discusses the success of that application. More recently, however, attempts were made to apply NET to advanced, thermal reactor designs such as the modular high-temperature gas reactor (MHTGR) and the new production heavy water reactor (NPR/HWR). The same methods that were successful for EBR-II have encountered problems for these reactors. Our preliminary analysis indicates that the sharp global flux gradients in these cores requires large discontinuity factors (greater than 4 or 5) to reproduce the reference solution. This disrupts the convergence of the iterative methods used to solve for the node-wise flux moments and partial currents. Several attempts to remedy the problem have been made over the last few years, including bounding the discontinuity factors and providing improved initial guesses for the flux solution, but nothing has been satisfactory.
Recurrence in Region of Spared Parotid Gland After Definitive Intensity-Modulated Radiotherapy for Head and Neck Cancer
Cannon, Donald M.; Lee, Nancy Y.
Purpose: To discuss the implications of three examples of periparotid recurrence after definitive intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC). Methods and Materials: We present 3 patients with HNC who underwent definitive IMRT with concurrent chemotherapy and later had treatment failure in or near a spared parotid gland. Two patients had bilateral multilevel nodal disease, and all had Level II nodal disease ipsilateral to the site of recurrence. The patients were treated using dose-painting IMRT with a dose of 70 Gy to the gross tumor volume and 59.4 Gy or 54 Gy to the high-risk or low-risk clinical tumor volume, respectively. The parotid glands were spared bilaterally. The patients had not undergone any surgical treatment for HNC before radiotherapy. Results: All patients had treatment failure in the region of a spared parotid gland. Failure in the 2 patients with bilateral multilevel nodal involvement occurred in the periparotid lymph nodes. The third patient developed a dermal metastasis near the tail of a spared parotid gland. On pretreatment imaging, the 2 patients with nodal failure had small nonspecific periparotid nodules that showed no hypermetabolic activity on positron emission tomography. Conclusion: For HNC patients receiving definitive IMRT, nonspecific positron emission tomography-negative periparotid nodules on pretreatment imaging should raise the index of suspicion for subclinical disease in the presence of multilevel or Level II nodal metastases. Additional evaluation of such nodules might be indicated before sparing the ipsilateral parotid gland.
Nodal Quasiparticle in Pseudogapped Colossal Magnetoresistive Manganites
Mannella, N.
A characteristic feature of the copper oxide high-temperature superconductors is the dichotomy between the electronic excitations along the nodal (diagonal) and antinodal (parallel to the Cu-O bonds) directions in momentum space, generally assumed to be linked to the d-wave symmetry of the superconducting state. Angle-resolved photoemission measurements in the superconducting state have revealed a quasiparticle spectrum with a d-wave gap structure that exhibits a maximum along the antinodal direction and vanishes along the nodal direction. Subsequent measurements have shown that, at low doping levels, this gap structure persists even in the high-temperature metallic state, although the nodal points of the superconducting state spread out in finite Fermi arcs. This is the so-called pseudogap phase, and it has been assumed that it is closely linked to the superconducting state, either by assigning it to fluctuating superconductivity or by invoking orders which are natural competitors of d-wave superconductors. Here we report experimental evidence that a very similar pseudogap state with a nodal-antinodal dichotomous character exists in a system that is markedly different from a superconductor: the ferromagnetic metallic groundstate of the colossal magnetoresistive bilayer manganite La{sub 1.2}Sr{sub 1.8}Mn{sub 2}O{sub 7}. Our findings therefore cast doubt on the assumption that the pseudogap state in the copper oxides and the nodal-antinodal dichotomy are hallmarks of the superconductivity state.
Continuous venovenous hemodialysis with regional citrate anticoagulation in patients with liver failure: a prospective observational study
Introduction Liver failure patients might be at risk for citrate accumulation during continuous venovenous hemodialysis (CVVHD) with regional citrate anticoagulation. The aim of this study was to investigate the predictive capability of baseline liver function parameters regarding citrate accumulation, expressed as an increase in the calcium total/calcium ionized (Catot/Caion) ratio ≥2.5, and to describe the feasibility of citrate CVVHD in liver failure patients. Methods We conducted a prospective observational study in medical ICU patients treated in a German university hospital. We performed 43 CVVHD runs using citrate for regional anticoagulation in 28 critically ill patients with decompensated liver cirrhosis or acute liver failure (maximum of two CVVHD runs per patient). Liver function was characterized before CVVHD using laboratory parameters, calculation of Child-Pugh and Model of End-stage Liver Disease scores, and determination of the plasma disappearance rate of indocyanine green. In addition to blood gas analysis, we measured total calcium and citrate in serum at baseline and after definitive time points for each CVVHD run. Results Accumulation of citrate in serum correlated with an increase in the Catot/Caion ratio. Although the critical upper threshold of Catot/Caion ratio ≥2.5 was exceeded 10 times in seven different CVVHD runs, equalization of initial metabolic acidosis was possible without major disturbances of acid-base and electrolyte status. Standard laboratory liver function parameters showed poor predictive capabilities regarding citrate accumulation in terms of an elevated Catot/Caion ratio ≥2.5. In contrast, serum lactate ≥3.4 mmol/l and prothrombin time ≤26% predicted an increase in the Catot/Caion ratio ≥2.5 with high sensitivity (86% for both lactate and prothrombin time) and specificity (86% for lactate, 92% for prothrombin time). Conclusions Despite substantial accumulation of citrate in serum, CVVHD with regional citrate
MURR nodal analysis with simple interactive simulation
NASA Astrophysics Data System (ADS)
Enani, Mohammad Abdulsamad
The main goal of this research is to design and produce computer codes that should do a NODAL analysis of the core of Missouri University Research Reactor 'MURR' with a simple neutron transient simulation. These codes should be executed on any of the family of the widely used modern IBM/PC (or IBM/PS) microcomputers (or compatibles). The nodal analysis code should find the power (or flux) distribution inside the reactor core and calculate fuel burnup for each of the fuel elements by using the nodal analysis technique described in chapter 3. The simulator code is a relatively simple, educational aid of MURR reactor kinetics simulation that uses one group point reactor model.
Aluminium metabolism in chronic renat failure: Environmental influences and regional differences in Norway.
Halse, J; Nordal, K P; Dahl, E; Thomassen, Y
Many aspects of Al metabolism in chronic renal failure are poorly understood. A longitudinal study of serum Al concentrations in predialysis patients and healthy control subjects revealed very high values during the autumn of 1984 and 1985. Renal Al clearance was low during the autumnal spike in serum Al but increased substantially when the serum Al concentration declined. A second study confirmed that by using citric acid as a chelator, the gastrointestinal absorption of Al from Al(OH)3 may be considerably augmented as reflected by increases in both serum Al concentrations and renal Al clearance. The individual differences in Al absorption in this study were large.The first study suggests the existence of an unidentified environmental factor, possibly water borne, with profound effects on Al absorption and excretion. The citric acid/Al(OH)3 experiment suggests that the existence of such a factor is likely. The implications of these results are not known.A histomorphometric study of bone biopsies from 138 hemodialysis and 66 predialysis patients without clinical evidence of Al related disease, revealed Al deposits after staining with aurin tricarboxylic acid in 78% of the biopsies from the former and 24% of the latter patients. Serum Al concentrations did not differ between predialysis and hemodialysis patients with Al positive biopsies. Stratification of the hemodialysis patients, who came from all parts of Norway, revealed that patients living in regions with slightly Al contaminated drinking water (Al <30 μg/L) had lower serum Al concentrations than patients from regions with highly contaminated water (Al >100 μg/L). The prevalence of Al-positive biopsies was the same in both regions. Patients with Al-positive biopsies did not differ in serum Al level from those with Al-negative biopsies within the same region. Predialysis patients with Al-positive biopsies had significantly higher serum Al levels than predialysis patients with Al negative biopsies
Performances and failure of field-aged PV modules operating in Saharan region of Algeria
NASA Astrophysics Data System (ADS)
Sadok, M.; Benyoucef, B.; Othmani, M.; Mehdaoui, A.
This article deals with behaviour of PV modules, of different technologies and manufacturers, exposed for long periods in Saharan region of Algeria. These modules are exposed in Adrar in the south-western part of Algeria. The study uses experimental I-V curves of PV modules for determining their performances. The datasheet information of modules will be useful in determination of degradation rates of the modules. Three types of modules have been tested: Photowatt (PWX 500), UDTS-50 and Isofoton (I-75 and I-100 serials). Results showed that Isofoton I-100 modules present the highest degradation rate while the lowest degradation rate was reached with I-75 serial. However, these rates tallies with other studies. The visual inspection of the modules has revealed various kinds of failures and defects responsible of performances drop (EVA browning, delamination, burn marks,…).
Nodal Stage of Surgically Resected Non-Small Cell Lung Cancer and Its Effect on Recurrence Patterns and Overall Survival
Varlotto, John M.; Yao, Aaron N.; DeCamp, Malcolm M.; Ramakrishna, Satvik; Recht, Abe; Flickinger, John; Andrei, Adin; Reed, Michael F.; Toth, Jennifer W.; Fizgerald, Thomas J.; Higgins, Kristin; Zheng, Xiao; Shelkey, Julie; and others
Purpose: Current National Comprehensive Cancer Network guidelines recommend postoperative radiation therapy (PORT) for patients with resected non-small cell lung cancer (NSCLC) with N2 involvement. We investigated the relationship between nodal stage and local-regional recurrence (LR), distant recurrence (DR) and overall survival (OS) for patients having an R0 resection. Methods and Materials: A multi-institutional database of consecutive patients undergoing R0 resection for stage I-IIIA NSCLC from 1995 to 2008 was used. Patients receiving any radiation therapy before relapse were excluded. A total of 1241, 202, and 125 patients were identified with N0, N1, and N2 involvement, respectively; 161 patients received chemotherapy. Cumulative incidence rates were calculated for LR and DR as first sites of failure, and Kaplan-Meier estimates were made for OS. Competing risk analysis and proportional hazards models were used to examine LR, DR, and OS. Independent variables included age, sex, surgical procedure, extent of lymph node sampling, histology, lymphatic or vascular invasion, tumor size, tumor grade, chemotherapy, nodal stage, and visceral pleural invasion. Results: The median follow-up time was 28.7 months. Patients with N1 or N2 nodal stage had rates of LR similar to those of patients with N0 disease, but were at significantly increased risk for both DR (N1, hazard ratio [HR] = 1.84, 95% confidence interval [CI]: 1.30-2.59; P=.001; N2, HR = 2.32, 95% CI: 1.55-3.48; P<.001) and death (N1, HR = 1.46, 95% CI: 1.18-1.81; P<.001; N2, HR = 2.33, 95% CI: 1.78-3.04; P<.001). LR was associated with squamous histology, visceral pleural involvement, tumor size, age, wedge resection, and segmentectomy. The most frequent site of LR was the mediastinum. Conclusions: Our investigation demonstrated that nodal stage is directly associated with DR and OS but not with LR. Thus, even some patients with, N0-N1 disease are at relatively high risk of local recurrence. Prospective
Nodal·Gdf1 Heterodimers with Bound Prodomains Enable Serum-independent Nodal Signaling and Endoderm Differentiation
Fuerer, Christophe; Nostro, M. Cristina; Constam, Daniel B.
The TGFβ family member Nodal is central to control pluripotent stem cell fate, but its use as a stem cell differentiation factor is limited by low specific activity. During development, Nodal depends on growth and differentiation factor (Gdf)-1 and on the shared co-receptor Cryptic to specify visceral left-right axis asymmetry. We therefore asked whether the functionality of Nodal can be augmented by Gdf1. Because Nodal and Gdf1 coimmunoprecipitate each other, they were predicted to form heterodimers, possibly to facilitate diffusion or to increase the affinity for signaling receptors. Here, we report that Gdf1 suppresses an unexpected dependence of Nodal on serum proteins and that it is critically required for non-autonomous signaling in cells expressing Cryptic. Nodal, Gdf1, and their cleaved propeptides copurified as a heterodimeric low molecular weight complex that stimulated Activin receptor (Acvr) signaling far more potently than Nodal alone. Although heterodimerization with Gdf1 did not increase binding of Nodal to Fc fusions of co-receptors or Acvr extracellular domains, it was essential for soluble Acvr2 to inhibit Nodal signaling. This implies that Gdf1 potentiates Nodal activity by stabilizing a low molecular weight fraction that is susceptible to neutralization by soluble Acvr2. Finally, in differentiating human ES cells, endodermal markers were more efficiently induced by Nodal·Gdf1 than by Nodal, suggesting that Nodal·Gdf1 is an attractive new reagent to direct stem cell differentiation. PMID:24798330
Pathology of extra-nodal non Hodgkin lymphomas.
Wright, D H
In the management of extra-nodal lymphomas it is important to determine whether the tumour has disseminated and whether lymph nodes are involved. Some extra-nodal lymphomas may be the result of random spread of nodal lymphoma. Specific homing, however, determines the site of many extra-nodal lymphomas, as exemplified by cutaneous T-cell lymphomas, which seem to be derived from skin-homing T-cells and mucosa-associated lymphoid tissue lymphomas that show features of the mucosal immune system. Enteropathy-associated T-cell lymphoma is derived from mucosal T-cells in patients with coeliac disease. Immunological sanctuary accounts for the localisation of primary brain, eye and testicular lymphoma. Mantle cell lymphoma frequently causes tumours in the gastrointestinal tract. Random biopsies have shown that a high proportion of patients with this lymphoma have extensive occult involvement of the gastrointestinal tract at the time of first diagnosis. Follicular lymphoma occurs at both nodal and extra-nodal sites, but uncommonly at both sites at the same time. Extra-nodal follicular lymphomas frequently lack t(14;18)(q32;q21) and do not express bcl-2, which are characteristics of the nodal disease. At extra-nodal sites, follicular lymphoma is more likely to be curable than nodal follicular lymphoma. The behaviour of extra-nodal lymphomas cannot be assumed to follow that of their nodal counterparts.
First Case of Automatic His Potential Detection With a Novel Ultra High-density Electroanatomical Mapping System for AV Nodal Ablation
Hilbert, Sebastian; Kosiuk, Jedrzej; John, Silke; Hindricks, Gerhard; Bollmann, Andreas
A 74-year old was considered for atrioventricular (AV) nodal ablation in view of atrial fibrillation (AF) with poorly controlled ventricular rate despite being on amiodarone. Targeted AV nodal ablation was successfully performed after identifying the target site for ablation by reviewing an ultra high-density map of the His region produced by automatic electrogram annotation. PMID:25852249
Nodal Diffusion Burnable Poison Treatment for Prismatic Reactor Cores
A. M. Ougouag; R. M. Ferrer
The prismatic block version of the High Temperature Reactor (HTR) considered as a candidate Very High Temperature Reactor (VHTR)design may use burnable poison pins in locations at some corners of the fuel blocks (i.e., assembly equivalent structures). The presence of any highly absorbing materials, such as these burnable poisons, within fuel blocks for hexagonal geometry, graphite-moderated High Temperature Reactors (HTRs) causes a local inter-block flux depression that most nodal diffusion-based method have failed to properly model or otherwise represent. The location of these burnable poisons near vertices results in an asymmetry in the morphology of the assemblies (or blocks). Hence the resulting inadequacy of traditional homogenization methods, as these "spread" the actually local effect of the burnable poisons throughout the assembly. Furthermore, the actual effect of the burnable poison is primarily local with influence in its immediate vicinity, which happens to include a small region within the same assembly as well as similar regions in the adjacent assemblies. Traditional homogenization methods miss this artifact entirely. This paper presents a novel method for treating the local effect of the burnable poison explicitly in the context of a modern nodal method.
The Upside of Failure: How Regional Student Groups Learn from Their Mistakes
Mishra, Tarun; Parra, R. Gonzalo; Abeel, Thomas
Success is the result of planning, hard work, determination, foresight, and a little bit of luck. Unfortunately, nobody has thought to pave the road to success. Although failure can be discouraging and time-consuming, it presents incredible learning opportunities—the biggest difference between those who succeed and those who abandon their projects lies in their response to adversity. This article reviews events undertaken by the Regional Student Groups (RSGs) in India and Argentina, the problems they encountered, and what can be learned from them. RSG-India attempted to organize an online scientific meeting (also known as a virtual conference) with geographically dispersed stakeholders, a totally new concept for them. RSG-Argentina tackled the challenge of organizing a two-day symposium, their first event ever. Some of the complications they faced were easy to fix, others led to the cancellation of activities, and all of them resulted in valuable lessons. The main goal of this article is to highlight, through their experiences, the universal importance of a healthy panel of contingency plans. PMID:25101799
Liver metastases from colorectal cancer: regional intra-arterial treatment following failure of systemic chemotherapy
Cyjon, A; Neuman-Levin, M; Rakowsky, E; Greif, F; Belinky, A; Atar, E; Hardoff, R; Brenner, B; Sulkes, A
This study was designed to determine response rate, survival and toxicity associated with combination chemotherapy delivered intra-arterially to liver in patients with hepatic metastases of colorectal origin refractory to standard systemic treatment. A total of 28 patients who failed prior systemic treatment with fluoropyrimidines received a median of 5 cycles of intra-arterial treatment consisting of 5-fluorouracil 700 mg/m2/d, leucovorin 120 mg/m2/d, and cisplatin 20 mg/m2/d for 5 consecutive days. Cycles were repeated at intervals of 5–6 weeks. A major response was achieved in 48% of patients: complete response in 8% and partial response in 40%. The median duration of response was 11.5 months. Median survival was 12 months at a median follow up of 12 months. On multivariate analysis, the only variables with a significant impact on survival were response to treatment and performance status. Toxicity was moderate: grades III–IV neutropenia occurred in 29% of patients. Most of the patients complained of fatigue lasting for a few days following each cycle. There were no cases of hepatobiliary toxicity. These findings indicate that regional intra-arterial treatment should be considered in selected patients with predominantly liver disease following failure of standard treatment. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11506487
Nodal resonance in a strong standing wave
NASA Astrophysics Data System (ADS)
Fernández C., David J.; Mielnik, Bogdan
The motion of charged particles in a standing electromagnetic wave is considered. For amplitudes that are not too high, the wave causes an effect of attraction of particles to the nodal points, resembling the channeling effect reported by Salomon, Dalibard, Aspect, Metcalf, and Cohen-Tannoudji [Phys. Rev. Lett. 59, 1659 (1987)] consistent with the ``high-frequency potential'' of Kapitza [Zh. Eksp. Teor. Fiz. 21, 588 (1951)]. For high-field intensities, however, the nodal points undergo a qualitative metamorphosis, converting themselves from particle attractors into resonant centers. Some chaotic phenomena arise and the description of the oscillating field in terms of an ``effective potential'' becomes inappropriate. The question of a correct Floquet Hamiltonian that could describe the standing wave within this amplitude and frequency regime is open.
Global and Regional Brain Mean Diffusivity Changes in Patients with Heart Failure
Woo, Mary A.; Palomares, Jose A.; Macey, Paul M.; Fonarow, Gregg C.; Harper, Ronald M.; Kumar, Rajesh
Heart failure (HF) patients show gray and white matter changes in multiple brain sites, including autonomic and motor coordination areas. It is unclear whether the changes represent acute or chronic tissue pathology, a distinction necessary for understanding pathological processes, and can be resolved with diffusion tensor imaging (DTI)-based mean diffusivity (MD) procedures. We collected four DTI series from 16 HF (age, 55.1±7.8 years; 12 male) and 26 controls (49.7±10.8 years; 17 male), using a 3.0-Tesla MRI scanner. MD maps were realigned, averaged, normalized, and smoothed. Global and regional MD values from autonomic and motor coordination sites were calculated using normalized MD maps and brain masks; group MD values and whole-brain smoothed MD maps were compared using analysis of covariance (covariates: age, gender). Global brain MD (HF vs. controls; Unit ×10−6 mm2/s; 1103.8±76.6 vs. 1035.9±69.4, p=0.038) and regional autonomic and motor site values (left insula, 1085.4±95.7 vs. 975.7±65.4, p=0.001; right insula, 1050.2±100.6 vs. 965.7±58.4, p=0.004; left hypothalamus, 1419.6±165.2 vs. 1234.9±136.3, p=0.002; right hypothalamus, 1446.5±178.8 vs. 1273.3±136.9, p=0.004; left cerebellar cortex, 889.1±81.9 vs. 796.6±46.8, p<0.001; right cerebellar cortex, 797.8±50.8 vs. 750.3±27.5, p=0.001; cerebellar deep nuclei, 1236.1±193.8 vs. 1071.7±107.1; p=0.002) were significantly higher in HF over controls, indicating chronic tissue changes. Whole-brain comparisons showed increased MD values in HF, including limbic, basal-ganglia, thalamic, solitary tract nucleus, frontal, and cerebellar regions. Brain injury occurs in autonomic and motor control areas, which may contribute to deficient functions in HF. The chronic tissue changes likely result from processes which develop over a prolonged time-period. PMID:25502071
Arbitrarily high order nodal and characteristic methods
Azmy, Y.Y.
The quest for higher computational efficiency initially led researchers in the neutron transport area to develop and implement high-order approximations for solving the linear Boltzmann equational. This drive aimed at achieving higher accuracy on coarse meshes, thereby resulting in a net savings of computational resources represented by execution time and memory. Many endeavors succeeded in reaching this goal, producing a variety of elegent, albeit complicated, formalisms, that proved extremely accurate and efficient in solving test, as well as practical applications, problems. The two main classes of high order transport methods that recieved the most attention are the Nodal and Characteristic methods. A de facto linear order standard for the spatial approximation (even though Quadratic Nodal Methods were also considered) was dictated by the algebraic complexity of the derivation of the discrete variable equations, the programming complexity of implementing and verifying them in codes, and limitations on computational resources available to run such codes. The significant advances in computational resources in terms of hardware capacity and speed, as well as architectural innovations such as vector and parallel processing, all but eliminated the third (above) obstacle towards the development and implementation of even higher order methods. The algebraic and programming complexities, on the other hand, were alleviated to some extent by the development of Arbitrarily High Order Transport methods of the Nodal and the Characteristic types, which are discussed in this report.
Multiple nodal locoregional recurrence of pheochromocytoma
Ramírez-Plaza, César Pablo; Cárdenas, Elena Margarita Sanchiz; Humanes, Rocío Soler
Introduction Malignancy is present in 10% of pheochromocytomas (PCC) and is defined as local/vascular infiltration of surrounding tissues or the presence of chromaffin cells deposits in distant organs. The presence of isolated nodal recurrence is very rare and only 7 cases have been reported in the medical literature. Presentation of the case The case of a 32-y male with a symptomatic recurrence of a previously operated (2-years ago) PCC is presented. Radiological and functional imaging studies confirmed the presence of multiple nodules in the surgical site. A radical left nephrectomy with extensive lymphatic clearance in order to get an R0 resection was performed. The pathologist confirmed the diagnosis of massive locoregional nodal invasion. Discussion A detailed histological report and a thorough genetic study must be considered in every operated PCC in order to identify mutations and profiles of risk for malignancy. When recurrence or metastastic disease is suspected, imaging and functional exams are done in order to obtain a proper staging. Radical surgery for the metastatic disease is the only treatment that may provide prolonged survival. If an R0 resection is not possible, then a debulking surgery is a good option when the benefit/risk ratio is acceptable. Conclusion Isolated lymph nodal recurrence is very rare in malignant PCC, with only 7 cases previously published. The role of surgery is essential to get long-term survival because provides clinical and functional control of the disease. PMID:26117450
Removal of maternal retinoic acid by embryonic CYP26 is required for correct Nodal expression during early embryonic patterning
Uehara, Masayuki; Yashiro, Kenta; Takaoka, Katsuyoshi; Yamamoto, Masamichi; Hamada, Hiroshi
The abundance of retinoic acid (RA) is determined by the balance between its synthesis by retinaldehyde dehydrogenase (RALDH) and its degradation by CYP26. In particular, the dynamic expression of three CYP26 genes controls the regional level of RA within the body. Pregastrulation mouse embryos express CYP26 but not RALDH. We now show that mice lacking all three CYP26 genes manifest duplication of the body axis as a result of expansion of the Nodal expression domain throughout the epiblast. Mouse Nodal was found to contain an RA-responsive element in intron 1 that is highly conserved among mammals. In the absence of CYP26, maternally derived RA activates Nodal expression in the entire epiblast of pregastrulation embryos via this element. These observations suggest that maternal RA must be removed by embryonic CYP26 for correct Nodal expression during embryonic patterning. PMID:19605690
Patterns of Locoregional Failure After Exclusive IMRT for Oropharyngeal Carcinoma
Sanguineti, Giuseppe Gunn, G. Brandon; Endres, Eugene J.; Chaljub, Gregory; Cheruvu, Praveena; Parker, Brent
Purpose: To assess the patterns of failure after intensity-modulated radiotherapy (IMRT) for oropharyngeal squamous cell carcinoma (SCC). Methods and Materials: We analyzed patients treated at the University of Texas Medical Branch between May 2002 and February 2006 who met the following criteria: (1) definitive IMRT without chemotherapy for oropharyngeal SCC; (2) no pretreatment radical surgery; (3) minimal follow-up of 1 year. The location of each nodal/primary failure was co-registered to the pretreatment planning computed tomography scan and then expanded by 5 mm to a planning target volume (PTV) of the failure (PTV-f). We then investigated whether the prescription dose to the PTV-f had been appropriate for the amount of disease present before treatment and whether the PTV-f had been adequately covered. Results: A total of 50 patients were eligible. With a median follow-up of 32.6 months (range, 12.1-58.6), three local and six regional failures were observed in 8 patients. All but one failure, that had been neglected, were recorded within 14 months of the treatment end. Of the nine failures, four developed in the neck treated electively to the lowest dose level; in all of them, we could retrospectively identify initial positive lymph nodes that might have justified the subsequent failure. The remaining five failures developed in proximity of the high-dose volume. In all but one, the volume of region of interest receiving {>=}95% of the dose of the PTV-f was >95%, suggesting adequate coverage. In 1 patient, about 20% of PTV-f was outside the 95% isodose, so that marginal underdosing could not be ruled out. Conclusions: A potential cause could be identified in all the failures in the lowest dose level. The implications and possible remedies are discussed. Most failures around the high-dose region were 'true failures' with no apparent technical caus000.
Expression and localization of nodal in bovine oviduct and uterus during different functional stages of oestrus cycle and pregnancy.
Argañaraz, Martin Eduardo; Apichela, Silvana Andrea; Kenngott, Rebecca; Vermeheren, Margarethe; Rodler, Daniela; Palma, Gustavo Adolfo; Miceli, Dora Cristina; Sinowatz, Fred
Members of TGF-β superfamily play a major role in the endometrial changes involved in the establishment and maintenance of pregnancy. Their deregulated expression and action could lead to absolute or partial failure of embryo implantation. Nonetheless, the precise function and mechanism of many of these cytokines remain unclear. Nodal, a transforming growth factor beta (TGF-β) superfamily member, was characterized in the human and rodent uterus and implicated in the tissue remodeling events during menstruation and embryo implantation. In order to study its possible role in the cattle reproductive process, we have analyzed Nodal expression pattern and localization in the oviduct and uterine horn during the oestrus cycle and early pregnancy (day 20). Nodal was detected both in oviduct and uterus during either the oestrus cycle or pregnancy; however, it shows a differential expression profile in the uterine horn at dioestrus and pregnancy, decreasing 1.5 and 1.4 folds in comparison with oestrus. Nodal immunostaining intensity was observed in stromal and in epithelial cells of the surface and the glandular epithelium. The staining pattern correlates with the RT-qPCR expression profile. This work is the first to evidence the presence of Nodal in the bovine reproductive tract; our data suggest that Nodal is a novel cytokine that would be involved in the remodelling occurring in the endometrium of cattle during the oestrus cycle and in the embryo implantation. The identification of new molecules that participate in endometrium cycling and/or pregnancy may be useful for predicting the ability of the uterine tissue to establish and maintain pregnancy or for detecting the infertility processes. These results highlight Nodal as a possible novel marker of the fertility process, nevertheless further studies should be done to determine its role in the reproductive system.
Small renal tumor with lymph nodal enlargement: A histopathological surprise
Thottathil, Mujeeburahiman; Verma, Ashish; D'souza, Nischith; Khan, Altaf
Renal cancer with lymph nodal mass on the investigation is clinically suggestive of an advanced tumor. Small renal cancers are not commonly associated with lymph nodal metastasis. Association of renal cell carcinoma with renal tuberculosis (TB) in the same kidney is also rare. We report here a case of small renal cancer with multiple hilar and paraaortic lymph nodes who underwent radical nephrectomy, and histopathology report showed renal and lymph nodal TB too. PMID:27453671
Plasticity underlies tumor progression: Role of Nodal signaling
Bodenstine, Thomas M.; Chandler, Grace S.; Seftor, Richard E. B.; Seftor, Elisabeth A.; Hendrix, Mary J. C.
The transforming growth factor beta (TGFβ) superfamily member Nodal is an established regulator of early embryonic development, with primary roles in endoderm induction, left-right asymmetry and primitive streak formation. Nodal signals through TGFβ family receptors at the plasma membrane and induces signaling cascades leading to diverse transcriptional regulation. While conceptually simple, the regulation of Nodal and its molecular effects are profoundly complex and context dependent. Pioneering work by developmental biologists has characterized the signaling pathways, regulatory components, and provided detailed insight into the mechanisms by which Nodal mediates changes at the cellular and organismal levels. Nodal is also an important factor in maintaining pluripotency of embryonic stem cells through regulation of core transcriptional programs. Collectively, this work has led to an appreciation for Nodal as a powerful morphogen capable of orchestrating multiple cellular phenotypes. Although Nodal is not active in most adult tissues, its re-expression and signaling have been linked to multiple types of human cancer, and Nodal has emerged as a driver of tumor growth and cellular plasticity. In vitro and in vivo experimental evidence has demonstrated that inhibition of Nodal signaling reduces cancer cell aggressive characteristics, while clinical data have established associations with Nodal expression and patient outcomes. As a result, there is great interest in the potential targeting of Nodal activity in a therapeutic setting for cancer patients that may provide new avenues for suppressing tumor growth and metastasis. In this review, we evaluate our current understanding of the complexities of Nodal function in cancer and highlight recent experimental evidence that sheds light on the therapeutic potential of its inhibition. PMID:26951550
Topological surface states in nodal superconductors.
Schnyder, Andreas P; Brydon, Philip M R
Topological superconductors have become a subject of intense research due to their potential use for technical applications in device fabrication and quantum information. Besides fully gapped superconductors, unconventional superconductors with point or line nodes in their order parameter can also exhibit nontrivial topological characteristics. This article reviews recent progress in the theoretical understanding of nodal topological superconductors, with a focus on Weyl and noncentrosymmetric superconductors and their protected surface states. Using selected examples, we review the bulk topological properties of these systems, study different types of topological surface states, and examine their unusual properties. Furthermore, we survey some candidate materials for topological superconductivity and discuss different experimental signatures of topological surface states.
Nodal lines and nodal loops in nonsymmorphic odd-parity superconductors
NASA Astrophysics Data System (ADS)
Micklitz, T.; Norman, M. R.
We discuss the nodal structure of odd-parity superconductors in the presence of nonsymmorphic crystal symmetries, both with and without spin-orbit coupling, and with and without time-reversal symmetry. We comment on the relation of our work to previous work in the literature, and also the implications for unconventional superconductors such as UPt3.
CAISO flicks switch on nodal scheme and lights stay on
In 2000-01, two years after introducing a competitive wholesale power auction in California - with a separate day-ahead zonal market operated by the California Power Exchange and a zonal market for ancillary services and balancing energy operated by the California Independent System Operator (CAISO) - the California market collapsed from exorbitant prices, flagrant gaming, and abuse of market power. Nine years later, CAISO introduced a nodal pricing auction for the wholesale market in April, replacing the zonal scheme, which was among many causes of the original market's demise. With nearly 3,000 nodes on the network, high prices in one region do not affect prices everywhere on the system. After investing some $200 million to upgrade the software, countless delays, and 18 months of market simulation and testing, the new auction was introduced and nothing unusual happened.
Nodal staging of colorectal carcinomas and sentinel nodes
Cserni, G
This review surveys the staging systems used for the classification of colorectal carcinomas, including the TNM system, and focuses on the assessment of the nodal stage of the disease. It reviews the quantitative requirements for a regional metastatic work up, and some qualitative features of lymph nodes that may help in the selection of positive and negative lymph nodes. Identification of the sentinel lymph nodes (those lymph nodes that have direct drainage from the primary tumour site) is one such qualitative feature that is claimed to allow the upstaging of colorectal carcinomas via an oriented, enhanced pathological work up. Current evidence in favour of a change in the requisite of assessing as may lymph nodes as is possible, and concentrating the efforts on only a selected number of lymph nodes, is weak. PMID:12719450
A composite nodal finite element for hexagons
Hennart, J.P.; Mund, E.H. |; Valle, E. Del
A nodal algorithm for the solution of the multigroup diffusion equations in hexagonal arrays is analyzed. Basically, the method consists of dividing each hexagon into four quarters and mapping the hexagon quarters onto squares. The resulting boundary value problem on a quadrangular domain is solved in primal weak formulation. Nodal finite element methods like the Raviart-Thomas RTk schemes provide accurate analytical expansions of the solution in the hexagons. Transverse integration cannot be performed on the equations in the quadrangular domain as simply as it is usually done on squares because these equations have essentially variable coefficients. However, by considering an auxiliary problem with constant coefficients (on the same quadrangular domain) and by using a preconditioning approach, transverse integration can be performed as for rectangular geometry. A description of the algorithm is given for a one-group diffusion equation. Numerical results are presented for a simple model problem with a known analytical solution and for k{sub eff} evaluations of some benchmark problems proposed in the literature. For the analytical problem, the results indicate that the theoretical convergence orders of RTk schemes (k = 0,1) are obtained, yielding accurate solutions at the expense of a few preconditioning iterations.
Disrupted Nodal and Hub Organization Account for Brain Network Abnormalities in Parkinson's Disease
Koshimori, Yuko; Cho, Sang-Soo; Criaud, Marion; Christopher, Leigh; Jacobs, Mark; Ghadery, Christine; Coakeley, Sarah; Harris, Madeleine; Mizrahi, Romina; Hamani, Clement; Lang, Anthony E.; Houle, Sylvain; Strafella, Antonio P.
The recent application of graph theory to brain networks promises to shed light on complex diseases such as Parkinson's disease (PD). This study aimed to investigate functional changes in sensorimotor and cognitive networks in Parkinsonian patients, with a focus on inter- and intra-connectivity organization in the disease-associated nodal and hub regions using the graph theoretical analyses. Resting-state functional MRI data of a total of 65 participants, including 23 healthy controls (HCs) and 42 patients, were investigated in 120 nodes for local efficiency, betweenness centrality, and degree. Hub regions were identified in the HC and patient groups. We found nodal and hub changes in patients compared with HCs, including the right pre-supplementary motor area (SMA), left anterior insula, bilateral mid-insula, bilateral dorsolateral prefrontal cortex (DLPFC), and right caudate nucleus. In general, nodal regions within the sensorimotor network (i.e., right pre-SMA and right mid-insula) displayed weakened connectivity, with the former node associated with more severe bradykinesia, and impaired integration with default mode network regions. The left mid-insula also lost its hub properties in patients. Within the executive networks, the left anterior insular cortex lost its hub properties in patients, while a new hub region was identified in the right caudate nucleus, paralleled by an increased level of inter- and intra-connectivity in the bilateral DLPFC possibly representing compensatory mechanisms. These findings highlight the diffuse changes in nodal organization and regional hub disruption accounting for the distributed abnormalities across brain networks and the clinical manifestations of PD. PMID:27891090
Nodal signaling and the evolution of deuterostome gastrulation.
Chea, Helen K; Wright, Christopher V; Swalla, Billie J
Chordates, including vertebrates, evolved within a group of animals called the deuterostomes. All holoblastic deuterostomes gastrulate at the vegetal pole and the blastopore becomes the anus, while a mouth is formed at the anterior or to the oral side. Nodal is a member of the TGF-beta superfamily of signaling molecules that are important in signaling between cells during many embryonic processes in vertebrate embryos. Nodal has also been found in other invertebrate deuterostomes, such as ascidians and sea urchins, but, so far, is missing in protostomes. Nodal has been shown to be particularly important in determining left-right asymmetries in vertebrate embryos, but less information is available for its developmental role in the invertebrate deuterostomes. We review gastrulation in the deuterostomes, then examine nodal expression early during mesoderm formation and later during the establishment of asymmetries in both vertebrates and invertebrates. Nodal is expressed asymmetrically on the left side in chordates and on the presumptive oral side of the embryo in echinoid echinoderms. The expression of nodal is in different germ layers in embryos of different phyla. Expression is in the ectoderm in most of the invertebrate deuterostomes, and in the mesoderm in vertebrates. We summarize the work that has been published to date, especially nodal expression in the invertebrate deuterostomes, and suggest future experiments to better understand the evolution of nodal signaling and deuterostome gastrulation.
Market redesign and technology upgrade: a nodal implementation
Isemonger, Alan G.
The California ISO and its market participants collectively cut over to a new nodal-based market on April 1, largely without incident and 11 years to the day from the initial startup in 1998. Thus far, the new nodal framework has proven robust, and the inevitable design and implementation issues that have emerged since cutover have been manageable. (author)
Radar response from vegetation with nodal structure
NASA Technical Reports Server (NTRS)
Blanchard, B. J.; Oneill, P. E.
Radar images from the SEASAT synthetic aperture radar (SAR) produced unusually high returns from corn and sorghum fields, which seem to indicate a correlation between nodal separation in the stalk and the wavelength of the radar. These images also show no difference in return from standing or harvested corn. Further investigation using images from the Shuttle Imaging Radar (SIR-A) substantiated these observations and showed a degradation of the high return with time after harvest. From portions of corn and sweet sorghum stalks that were sampled to measure stalk water content, it was determined that near and after maturity the water becomes more concentrated in the stalk nodes. The stalk then becomes a linear sequence of alternating dielectrics as opposed to a long slender cylinder with uniform dielectric properties.
Experience with advanced nodal codes at YAEC
Cacciapouti, R.J.
Yankee Atomic Electric Company (YAEC) has been performing reload licensing analysis since 1969. The basic pressurized water reactor (PWR) methodology involves the use of LEOPARD for cross-section generation, PDQ for radial power distributions and integral control rod worth, and SIMULATE for axial power distributions and differential control rod worth. In 1980, YAEC began performing reload licensing analysis for the Vermont Yankee boiling water reactor (BWR). The basic BWR methodology involves the use of CASMO for cross-section generation and SIMULATE for three-dimensional power distributions. In 1986, YAEC began investigating the use of CASMO-3 for cross-section generation and the advanced nodal code SIMULATE-3 for power distribution analysis. Based on the evaluation, the CASMO-3/SIMULATE-3 methodology satisfied all requirements. After careful consideration, the cost of implementing the new methodology is expected to be offset by reduced computing costs, improved engineering productivity, and fuel-cycle performance gains.
Regional tissue oximetry reflects changes in arterial flow in porcine chronic heart failure treated with venoarterial extracorporeal membrane oxygenation.
Hála, P; Mlček, M; Ošťádal, P; Janák, D; Popková, M; Bouček, T; Lacko, S; Kudlička, J; NeuŽil, P; Kittnar, O
Venoarterial extracorporeal membrane oxygenation (VA ECMO) is widely used in treatment of decompensated heart failure. Our aim was to investigate its effects on regional perfusion and tissue oxygenation with respect to extracorporeal blood flow (EBF). In five swine, decompensated low-output chronic heart failure was induced by long-term rapid ventricular pacing. Subsequently, VA ECMO was introduced and left ventricular (LV) volume, aortic blood pressure, regional arterial flow and tissue oxygenation were continuously recorded at different levels of EBF. With increasing EBF from minimal to 5 l/min, mean arterial pressure increased from 47+/-22 to 84+/-12 mm Hg (P<0.001) and arterial blood flow increased in carotid artery from 211+/-72 to 479+/-58 ml/min (P<0.01) and in subclavian artery from 103+/-49 to 296+/-54 ml/min (P<0.001). Corresponding brain and brachial tissue oxygenation increased promptly from 57+/-6 to 74+/-3 % and from 37+/-6 to 77+/-6 %, respectively (both P<0.01). Presented results confirm that VA ECMO is a capable form of heart support. Regional arterial flow and tissue oxygenation suggest that partial circulatory support may be sufficient to supply brain and peripheral tissue by oxygen.
Influence of Pathological Nodal Status and Maximal Standardized Uptake Value of the Primary Tumor and Regional Lymph Nodes on Treatment Plans in Patients With Advanced Oral Cavity Squamous Cell Carcinoma
Liao, C.-T.; Wang, H.-M.; Chang, Joseph Tung-Chieh; Lin, C.-Y.; Ng, S.-H.; Huang, S.-F.; Chen, I.-H.; Hsueh Chuen; Lee, L.-Y.; Lin, C.-H.
Purpose: A better understanding of the prognostic factors in oral cavity squamous cell carcinoma (OSCC) may optimize the therapeutic approach. In this study, we sought to investigate whether the combination of clinical information, pathologic results, and preoperative maximal standardized uptake value (SUVmax) at the primary tumor and regional lymph nodes might improve the prognostic stratification in this patient group. Methods and Materials: A total of 347 consecutive OSCC patients were investigated. All participants underwent fluorodeoxyglucose-positron emission tomography within 2 weeks before surgery and neck dissection. The duration of follow-up was at least 24 months in all surviving patients. The optimal cutoff values for SUVmax at the primary tumor (SUVtumor-max) and regional lymph nodes (SUVnodal-max) were selected according to the 5-year disease-free survival (DFS) rate. Independent prognosticators were identified by Cox regression analysis. Results: In multivariate analysis, a cutoff SUVtumor-max of 8.6, a cutoff SUVnodal-max of 5.7, and the presence of pathologic lymph node metastases were found to be significant prognosticators for the 5-year DFS. A scoring system using these three prognostic factors was formulated to define distinct prognostic groups. The 5-year rates for patients with a score between 0 and 3 were as follows: neck control, 94%, 86%, 77%, 59% (p < 0.0001); distant metastases, 1%, 7%, 22%, 47% (p < 0.0001); disease-specific survival, 93%, 85%, 61%, 36%, respectively (p < 0.0001). Conclusion: Based on the study findings, the combined evaluation of pathologic node status and SUVmax at the primary tumor and regional lymph nodes may improve prognostic stratification in OSCC patients.
Incessant junctional reciprocating tachycardia caused by dual atrioventricular nodal pathways and atrio-nodal bypass tract.
Santarelli, P; Sosa, E; Denes, P
A case is described with clinical and electrocardiographic findings of incessant junctional reciprocating tachycardia. Electrophysiological study showed that longitudinal dissociation of the atrioventricular node into two pathways was responsible for the maintenance of the arrhythmia. The two intranodal pathways had different refractory periods but reciprocally related and overlapping conduction times (anterograde fast, retrograde slow, and vice versa). Induction and termination of the arrhythmia was related to the presence of a partial atrio-nodal bypass tract. Images PMID:7082510
Chest wall regional volume in heart failure patients during inspiratory loaded breathing.
Brandão, Daniella Cunha; Lage, Susan Martins; Britto, Raquel Rodrigues; Parreira, Verônica Franco; de Oliveira, Wilson Alves; Martins, Sílvia Marinho; Aliverti, Andrea; de Andrade Carvalho, Larissa; do Nascimento Junior, Jasiel Frutuoso; Alcoforado, Luciana; Remígio, Inês; de Andrade, Armele Dornelas
Were evaluated individuals divided into two groups: we studied chronic heart failure (CHF) (19 patients with CHF plus cardiomegaly) and control (12 healthy volunteers) during performance of inspiratory loaded breathing (ILB). We evaluated: spirometry, functional capacity through the six-minute walk test (6MWT), and distribution of thoracoabdominal volumes via optoelectronic plethysmography (OEP), namely volume variations of pulmonary rib cage (Vrc,p), abdominal rib cage (Vrc,a), and abdomen (Vab). In each compartment, the percentage contributions of right and left sides were also calculated. During ILB, patients with heart failure were characterized by a significant reduction of the Vrc,a volume variations compared to the control group. Correlations were found between left %Vrc,a on the left side measured during ILB and left ventricular ejection fraction (r=0.468; p=0.049), and dyspnea after the 6MWT (r=-0.878; p<0.01).Then, patients with CHF and cardiomegaly are characterized by a reduced mobility in left part of the lower part of the rib cage, that contributes leading to increased perception of dyspnea during submaximal exercise.
Exploratory Investigation of Failure Mechanisms in Transition Regions between Solid Laminates and X-cor(registered tm) Truss Sandwich
NASA Technical Reports Server (NTRS)
OBrien, T. Kevin; Paris, Isabelle L.
Small sub-component specimens consisting of solid laminates at the ends that transition to X-cor(R) truss sandwich in the center, were tested in a combination of three point bending, uni-axial tension, and combined tension and bending. The failure process in the transition region was documented for each loading using digital video and high-resolution cameras. For the 3-point bending tests, most of the deformation occurred in the solid laminate regions on either end of the specimen. Some pin debonding from the skin of the X-cor(R) truss sandwich was observed in the transition region and was accompanied by audible "pings" throughout the loading. Tension loaded specimens failed in the sandwich skin in the middle of the gage length, accompanied by separation of the sandwich core from the back skin and by delamination between the top skin and bottom skin at the transition region. The pinging associated with pin debonding occurred as the load was increased. However, the frequency of the pinging exceeded any visual observations of pin debonding in the video of the transition region. For specimens tested in combined tension and bending, the greatest amount of pinging occurred during initial application of the axial load. High-resolution images in the transition region indicated that the pinging corresponded to pins debonding and buckling due to the through-thickness Poisson contraction of the specimen. This buckling continued to a much smaller extent as the transverse load was applied.
Heart failure in patients presenting with dyspnoea to the emergency department in the Asia Pacific region: an observational study
Kelly, Anne-Maree; Cullen, Louise; Klim, Sharon; Craig, Simon; Kuan, Win Sen; Jones, Peter; Holdgate, Anna; Lawoko, Charles; Laribi, Said
Objectives To describe demographic features, assessment, management and outcomes of patients who were diagnosed with heart failure after presenting to an emergency department (ED) with a principal symptom of dyspnoea. Design Planned substudy of the prospective, descriptive cohort study: Asia, Australia and New Zealand Dyspnoea in Emergency Departments (AANZDEM). Setting 46 EDs in Australia, New Zealand, Singapore, Hong Kong and Malaysia collected data over 3 72-hour periods in May, August and October 2014. Participants Patients with an ED diagnosis of heart failure. Outcome measures Outcomes included patient epidemiology, investigations ordered, treatment modalities used and patient outcomes (hospital length of stay (LOS) and mortality). Results 455 (14.9%) of the 3044 patients had an ED diagnosis of heart failure. Median age was 79 years, half were male and 62% arrived via ambulance. 392 (86%) patients were admitted to hospital. ED diagnosis was concordant with hospital discharge diagnosis in 81% of cases. Median hospital LOS was 6 days (IQR 4–9) and in-hospital mortality was 5.1%. Natriuretic peptide levels were ordered in 19%, with lung ultrasound (<1%) and echocardiography (2%) uncommonly performed. Treatment modalities included non-invasive ventilation (12%), diuretics (73%), nitrates (25%), antibiotics (16%), inhaled β-agonists (13%) and corticosteroids (6%). Conclusions In the Asia Pacific region, heart failure is a common diagnosis among patients presenting to the ED with a principal symptom of dyspnoea. Admission rates were high and ED diagnostic accuracy was good. Despite the seemingly suboptimal adherence to investigation and treatment guidelines, patient outcomes were favourable compared with other registries. PMID:28246137
B. D. Ganapol; D. W. Nigg
In the mid 80's, a four-group/two-region, entirely analytical 1D nodal benchmark appeared. It was readily acknowledged that this special case was as far as one could go in terms of group number and still achieve an analytical solution. In this work, we show that by decomposing the solution to the multigroup diffusion equation into homogeneous and particular solutions, extension to any number of groups is a relatively straightforward exercise using the mathematics of linear algebra.
Designer Nodal/BMP2 Chimeras Mimic Nodal Signaling, Promote Chondrogenesis, and Reveal a BMP2-like Structure
Esquivies, Luis; Blackler, Alissa; Peran, Macarena; Rodriguez-Esteban, Concepcion; Izpisua Belmonte, Juan Carlos; Booker, Evan; Gray, Peter C.; Ahn, Chihoon; Kwiatkowski, Witek; Choe, Senyon
Nodal, a member of the TGF-β superfamily, plays an important role in vertebrate and invertebrate early development. The biochemical study of Nodal and its signaling pathway has been a challenge, mainly because of difficulties in producing the protein in sufficient quantities. We have developed a library of stable, chemically refoldable Nodal/BMP2 chimeric ligands (NB2 library). Three chimeras, named NB250, NB260, and NB264, show Nodal-like signaling properties including dependence on the co-receptor Cripto and activation of the Smad2 pathway. NB250, like Nodal, alters heart looping during the establishment of embryonic left-right asymmetry, and both NB250 and NB260, as well as Nodal, induce chondrogenic differentiation of human adipose-derived stem cells. This Nodal-induced differentiation is shown to be more efficient than BPM2-induced differentiation. Interestingly, the crystal structure of NB250 shows a backbone scaffold similar to that of BMP2. Our results show that these chimeric ligands may have therapeutic implications in cartilage injuries. PMID:24311780
Celiac Node Failure Patterns After Definitive Chemoradiation for Esophageal Cancer in the Modern Era
Amini, Arya; Xiao Lianchun; Allen, Pamela K.; Suzuki, Akihiro; Hayashi, Yuki; Liao, Zhongxing; Hofstetter, Wayne; Crane, Christopher; Komaki, Ritsuko; Bhutani, Manoop S.; Lee, Jeffrey H.; Ajani, Jaffer A.; Welsh, James
Purpose: The celiac lymph node axis acts as a gateway for metastatic systemic spread. The need for prophylactic celiac nodal coverage in chemoradiation therapy for esophageal cancer is controversial. Given the improved ability to evaluate lymph node status before treatment via positron emission tomography (PET) and endoscopic ultrasound, we hypothesized that prophylactic celiac node irradiation may not be needed for patients with localized esophageal carcinoma. Methods and Materials: We reviewed the radiation treatment volumes for 131 patients who underwent definitive chemoradiation for esophageal cancer. Patients with celiac lymph node involvement at baseline were excluded. Median radiation dose was 50.4 Gy. The location of all celiac node failures was compared with the radiation treatment plan to determine whether the failures occurred within or outside the radiation treatment field. Results: At a median follow-up time of 52.6 months (95% CI 46.1-56.7 months), 6 of 60 patients (10%) without celiac node coverage had celiac nodal failure; in 5 of these patients, the failures represented the first site of recurrence. Of the 71 patients who had celiac coverage, only 5 patients (7%) had celiac region relapse. In multivariate analyses, having a pretreatment-to-post-treatment change in standardized uptake value on PET >52% (odds ratio [OR] 0.198, p = 0.0327) and having failure in the clinical target volume (OR 10.72, p = 0.001) were associated with risk of celiac region relapse. Of those without celiac coverage, the 6 patients that later developed celiac failure had a worse median overall survival time compared with the other 54 patients who did not fail (median overall survival time: 16.5 months vs. 31.5 months, p = 0.041). Acute and late toxicities were similar in both groups. Conclusions: Although celiac lymph node failures occur in approximately 1 of 10 patients, the lack of effective salvage treatments and subsequent low morbidity may justify prophylactic treatment
An analytical discrete ordinates solution for a nodal model of a two-dimensional neutron transport problem
Filho, J. F. P.
In this work, an analytical discrete ordinates method is used to solve a nodal formulation of a neutron transport problem in x, y-geometry. The proposed approach leads to an important reduction in the order of the associated eigenvalue systems, when combined with the classical level symmetric quadrature scheme. Auxiliary equations are proposed, as usually required for nodal methods, to express the unknown fluxes at the boundary introduced as additional unknowns in the integrated equations. Numerical results, for the problem defined by a two-dimensional region with a spatially constant and isotropically emitting source, are presented and compared with those available in the literature. (authors)
Nodal Solutions for Supercritical Laplace Equations
NASA Astrophysics Data System (ADS)
Dalbono, Francesca; Franca, Matteo
In this paper we study radial solutions for the following equation Δ u(x)+f (u(x), |x|) = 0, where {x in {Rn}}, n > 2, f is subcritical for r small and u large and supercritical for r large and u small, with respect to the Sobolev critical exponent {2^{*} = 2n/n-2}. The solutions are classified and characterized by their asymptotic behaviour and nodal properties. In an appropriate super-linear setting, we give an asymptotic condition sufficient to guarantee the existence of at least one ground state with fast decay with exactly j zeroes for any j ≥ 0. Under the same assumptions, we also find uncountably many ground states with slow decay, singular ground states with fast decay and singular ground states with slow decay, all of them with exactly j zeroes. Our approach, based on Fowler transformation and invariant manifold theory, enables us to deal with a wide family of potentials allowing spatial inhomogeneity and a quite general dependence on u. In particular, for the Matukuma-type potential, we show a kind of structural stability.
The genetics of nodal marginal zone lymphoma
Spina, Valeria; Khiabanian, Hossein; Messina, Monica; Monti, Sara; Cascione, Luciano; Bruscaggin, Alessio; Spaccarotella, Elisa; Holmes, Antony B.; Arcaini, Luca; Lucioni, Marco; Tabbò, Fabrizio; Zairis, Sakellarios; Diop, Fary; Cerri, Michaela; Chiaretti, Sabina; Marasca, Roberto; Ponzoni, Maurilio; Deaglio, Silvia; Ramponi, Antonio; Tiacci, Enrico; Pasqualucci, Laura; Paulli, Marco; Falini, Brunangelo; Inghirami, Giorgio; Bertoni, Francesco; Foà, Robin; Rabadan, Raul; Gaidano, Gianluca
Nodal marginal zone lymphoma (NMZL) is a rare, indolent B-cell tumor that is distinguished from splenic marginal zone lymphoma (SMZL) by the different pattern of dissemination. NMZL still lacks distinct markers and remains orphan of specific cancer gene lesions. By combining whole-exome sequencing, targeted sequencing of tumor-related genes, whole-transcriptome sequencing, and high-resolution single nucleotide polymorphism array analysis, we aimed at disclosing the pathways that are molecularly deregulated in NMZL and we compare the molecular profile of NMZL with that of SMZL. These analyses identified a distinctive pattern of nonsilent somatic lesions in NMZL. In 35 NMZL patients, 41 genes were found recurrently affected in ≥3 (9%) cases, including highly prevalent molecular lesions of MLL2 (also known as KMT2D; 34%), PTPRD (20%), NOTCH2 (20%), and KLF2 (17%). Mutations of PTPRD, a receptor-type protein tyrosine phosphatase regulating cell growth, were enriched in NMZL across mature B-cell tumors, functionally caused the loss of the phosphatase activity of PTPRD, and were associated with cell-cycle transcriptional program deregulation and increased proliferation index in NMZL. Although NMZL shared with SMZL a common mutation profile, NMZL harbored PTPRD lesions that were otherwise absent in SMZL. Collectively, these findings provide new insights into the genetics of NMZL, identify PTPRD lesions as a novel marker for this lymphoma across mature B-cell tumors, and support the distinction of NMZL as an independent clinicopathologic entity within the current lymphoma classification. PMID:27335277
The ancestral role of nodal signalling in breaking L/R symmetry in the vertebrate forebrain.
Lagadec, Ronan; Laguerre, Laurent; Menuet, Arnaud; Amara, Anis; Rocancourt, Claire; Péricard, Pierre; Godard, Benoît G; Rodicio, Maria Celina; Rodriguez-Moldes, Isabel; Mayeur, Hélène; Rougemont, Quentin; Mazan, Sylvie; Boutet, Agnès
Left-right asymmetries in the epithalamic region of the brain are widespread across vertebrates, but their magnitude and laterality varies among species. Whether these differences reflect independent origins of forebrain asymmetries or taxa-specific diversifications of an ancient vertebrate feature remains unknown. Here we show that the catshark Scyliorhinus canicula and the lampreys Petromyzon marinus and Lampetra planeri exhibit conserved molecular asymmetries between the left and right developing habenulae. Long-term pharmacological treatments in these species show that nodal signalling is essential to their generation, rather than their directionality as in teleosts. Moreover, in contrast to zebrafish, habenular left-right differences are observed in the absence of overt asymmetry of the adjacent pineal field. These data support an ancient origin of epithalamic asymmetry, and suggest that a nodal-dependent asymmetry programme operated in the forebrain of ancestral vertebrates before evolving into a variable trait in bony fish.
Nodal aberration theory for wild-filed asymmetric optical systems
NASA Astrophysics Data System (ADS)
Chen, Yang; Cheng, Xuemin; Hao, Qun
Nodal Aberration Theory (NAT) was used to calculate the zero field position in Full Field Display (FFD) for the given aberration term. Aiming at wide-filed non-rotational symmetric decentered optical systems, we have presented the nodal geography behavior of the family of third-order and fifth-order aberrations. Meanwhile, we have calculated the wavefront aberration expressions when one optical element in the system is tilted, which was not at the entrance pupil. By using a three-piece-cellphone lens example in optical design software CodeV, the nodal geography is testified under several situations; and the wavefront aberrations are calculated when the optical element is tilted. The properties of the nodal aberrations are analyzed by using Fringe Zernike coefficients, which are directly related with the wavefront aberration terms and usually obtained by real ray trace and wavefront surface fitting.
Nodal signalling and asymmetry of the nervous system.
Signore, Iskra A; Palma, Karina; Concha, Miguel L
The role of Nodal signalling in nervous system asymmetry is still poorly understood. Here, we review and discuss how asymmetric Nodal signalling controls the ontogeny of nervous system asymmetry using a comparative developmental perspective. A detailed analysis of asymmetry in ascidians and fishes reveals a critical context-dependency of Nodal function and emphasizes that bilaterally paired and midline-unpaired structures/organs behave as different entities. We propose a conceptual framework to dissect the developmental function of Nodal as asymmetry inducer and laterality modulator in the nervous system, which can be used to study other types of body and visceral organ asymmetries. Using insights from developmental biology, we also present novel evolutionary hypotheses on how Nodal led the evolution of directional asymmetry in the brain, with a particular focus on the epithalamus. We intend this paper to provide a synthesis on how Nodal signalling controls left-right asymmetry of the nervous system.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.
A Novel Risk Stratification to Predict Local-Regional Failures in Urothelial Carcinoma of the Bladder After Radical Cystectomy
Baumann, Brian C.; Guzzo, Thomas J.; He Jiwei; Keefe, Stephen M.; Tucker, Kai; Bekelman, Justin E.; Hwang, Wei-Ting; Vaughn, David J.; Malkowicz, S. Bruce; Christodouleas, John P.
Purpose: Local-regional failures (LF) following radical cystectomy (RC) plus pelvic lymph node dissection (PLND) with or without chemotherapy for invasive urothelial bladder carcinoma are more common than previously reported. Adjuvant radiation therapy (RT) could reduce LF but currently has no defined role because of previously reported morbidity. Modern techniques with improved normal tissue sparing have rekindled interest in RT. We assessed the risk of LF and determined those factors that predict recurrence to facilitate patient selection for future adjuvant RT trials. Methods and Materials: From 1990-2008, 442 patients with urothelial bladder carcinoma at University of Pennsylvania were prospectively followed after RC plus PLND with or without chemotherapy with routine pelvic computed tomography (CT) or magnetic resonance imaging (MRI). One hundred thirty (29%) patients received chemotherapy. LF was any pelvic failure detected before or within 3 months of distant failure. Competing risk analyses identified factors predicting increased LF risk. Results: On univariate analysis, pathologic stage {>=}pT3, <10 nodes removed, positive margins, positive nodes, hydronephrosis, lymphovascular invasion, and mixed histology significantly predicted LF; node density was marginally predictive, but use of chemotherapy, number of positive nodes, type of surgical diversion, age, gender, race, smoking history, and body mass index were not. On multivariate analysis, only stage {>=}pT3 and <10 nodes removed were significant independent LF predictors with hazard ratios of 3.17 and 2.37, respectively (P<.01). Analysis identified 3 patient subgroups with significantly different LF risks: low-risk ({<=}pT2), intermediate-risk ({>=}pT3 and {>=}10 nodes removed), and high-risk ({>=}pT3 and <10 nodes) with 5-year LF rates of 8%, 23%, and 42%, respectively (P<.01). Conclusions: This series using routine CT and MRI surveillance to detect LF confirms that such failures are relatively common
An amphioxus nodal gene (AmphiNodal) with early symmetrical expression in the organizer and mesoderm and later asymmetrical expression associated with left-right axis formation
NASA Technical Reports Server (NTRS)
Yu, Jr-Kai; Holland, Linda Z.; Holland, Nicholas D.
The full-length sequence and zygotic expression of an amphioxus nodal gene are described. Expression is first detected in the early gastrula just within the dorsal lip of the blastopore in a region of hypoblast that is probably comparable with the vertebrate Spemann's organizer. In the late gastrula and early neurula, expression remains bilaterally symmetrical, limited to paraxial mesoderm and immediately overlying regions of the neural plate. Later in the neurula stage, all neural expression disappears, and mesodermal expression disappears from the right side. All along the left side of the neurula, mesodermal expression spreads into the left side of the gut endoderm. Soon thereafter, all expression is down-regulated except near the anterior and posterior ends of the animal, where transcripts are still found in the mesoderm and endoderm on the left side. At this time, expression also begins in the ectoderm on the left side of the head, in the region where the mouth later forms. These results suggest that amphioxus and vertebrate nodal genes play evolutionarily conserved roles in establishing Spemann's organizer, patterning the mesoderm rostrocaudally and setting up the asymmetrical left-right axis of the body.
Failure of lysosome clustering and positioning in the juxtanuclear region in cells deficient in rapsyn
Aittaleb, Mohamed; Chen, Po-Ju; Akaaboune, Mohammed
ABSTRACT Rapsyn, a scaffold protein, is required for the clustering of acetylcholine receptors (AChRs) at contacts between motor neurons and differentiating muscle cells. Rapsyn is also expressed in cells that do not express AChRs. However, its function in these cells remains unknown. Here, we show that rapsyn plays an AChR-independent role in organizing the distribution and mobility of lysosomes. In cells devoid of AChRs, rapsyn selectively induces the clustering of lysosomes at high density in the juxtanuclear region without affecting the distribution of other intracellular organelles. However, when the same cells overexpress AChRs, rapsyn is recruited away from lysosomes to colocalize with AChR clusters on the cell surface. In rapsyn-deficient (Rapsn−/−) myoblasts or cells overexpressing rapsyn mutants, lysosomes are scattered within the cell and highly dynamic. The increased mobility of lysosomes in Rapsn−/− cells is associated with a significant increase in lysosomal exocytosis, as evidenced by increased release of lysosomal enzymes and plasma membrane damage when cells were challenged with the bacterial pore-forming toxin streptolysin-O. These findings uncover a new link between rapsyn, lysosome positioning, exocytosis and plasma membrane integrity. PMID:26330529
Programming and isolation of highly pure physiologically and pharmacologically functional sinus-nodal bodies from pluripotent stem cells.
Jung, Julia Jeannine; Husse, Britta; Rimmbach, Christian; Krebs, Stefan; Stieber, Juliane; Steinhoff, Gustav; Dendorfer, Andreas; Franz, Wolfgang-Michael; David, Robert
Therapeutic approaches for "sick sinus syndrome" rely on electrical pacemakers, which lack hormone responsiveness and bear hazards such as infection and battery failure. These issues may be overcome via "biological pacemakers" derived from pluripotent stem cells (PSCs). Here, we show that forward programming of PSCs with the nodal cell inducer TBX3 plus an additional Myh6-promoter-based antibiotic selection leads to cardiomyocyte aggregates consisting of >80% physiologically and pharmacologically functional pacemaker cells. These induced sinoatrial bodies (iSABs) exhibited highly increased beating rates (300-400 bpm), coming close to those found in mouse hearts, and were able to robustly pace myocardium ex vivo. Our study introduces iSABs as highly pure, functional nodal tissue that is derived from PSCs and may be important for future cell therapies and drug testing in vitro.
Programming and Isolation of Highly Pure Physiologically and Pharmacologically Functional Sinus-Nodal Bodies from Pluripotent Stem Cells
Jung, Julia Jeannine; Husse, Britta; Rimmbach, Christian; Krebs, Stefan; Stieber, Juliane; Steinhoff, Gustav; Dendorfer, Andreas; Franz, Wolfgang-Michael; David, Robert
Summary Therapeutic approaches for "sick sinus syndrome" rely on electrical pacemakers, which lack hormone responsiveness and bear hazards such as infection and battery failure. These issues may be overcome via "biological pacemakers" derived from pluripotent stem cells (PSCs). Here, we show that forward programming of PSCs with the nodal cell inducer TBX3 plus an additional Myh6-promoter-based antibiotic selection leads to cardiomyocyte aggregates consisting of >80% physiologically and pharmacologically functional pacemaker cells. These induced sinoatrial bodies (iSABs) exhibited highly increased beating rates (300–400 bpm), coming close to those found in mouse hearts, and were able to robustly pace myocardium ex vivo. Our study introduces iSABs as highly pure, functional nodal tissue that is derived from PSCs and may be important for future cell therapies and drug testing in vitro. PMID:24936448
Accuracy of Computed Tomography for Predicting Pathologic Nodal Extracapsular Extension in Patients With Head-and-Neck Cancer Undergoing Initial Surgical Resection
Prabhu, Roshan S.; Magliocca, Kelly R.; Hanasoge, Sheela; Aiken, Ashley H.; Hudgins, Patricia A.; Hall, William A.; Chen, Susie A.; Eaton, Bree R.; Higgins, Kristin A.; Saba, Nabil F.; Beitler, Jonathan J.
Purpose: Nodal extracapsular extension (ECE) in patients with head-and-neck cancer increases the loco-regional failure risk and is an indication for adjuvant chemoradiation therapy (CRT). To reduce the risk of requiring trimodality therapy, patients with head-and-neck cancer who are surgical candidates are often treated with definitive CRT when preoperative computed tomographic imaging suggests radiographic ECE. The purpose of this study was to assess the accuracy of preoperative CT imaging for predicting pathologic nodal ECE (pECE). Methods and Materials: The study population consisted of 432 consecutive patients with oral cavity or locally advanced/nonfunctional laryngeal cancer who underwent preoperative CT imaging before initial surgical resection and neck dissection. Specimens with pECE had the extent of ECE graded on a scale from 1 to 4. Results: Radiographic ECE was documented in 46 patients (10.6%), and pECE was observed in 87 (20.1%). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 43.7%, 97.7%, 82.6%, and 87.3%, respectively. The sensitivity of radiographic ECE increased from 18.8% for grade 1 to 2 ECE, to 52.9% for grade 3, and 72.2% for grade 4. Radiographic ECE criteria of adjacent structure invasion was a better predictor than irregular borders/fat stranding for pECE. Conclusions: Radiographic ECE has poor sensitivity, but excellent specificity for pECE in patients who undergo initial surgical resection. PPV and NPV are reasonable for clinical decision making. The performance of preoperative CT imaging increased as pECE grade increased. Patients with resectable head-and-neck cancer with radiographic ECE based on adjacent structure invasion are at high risk for high-grade pECE requiring adjuvant CRT when treated with initial surgery; definitive CRT as an alternative should be considered where appropriate.
Nodal endoplasmic reticulum, a specialized form of endoplasmic reticulum found in gravity-sensing root tip columella cells
NASA Technical Reports Server (NTRS)
Zheng, H. Q.; Staehelin, L. A.
The endoplasmic reticulum (ER) of columella root cap cells has been postulated to play a role in gravity sensing. We have re-examined the ultrastructure of columella cells in tobacco (Nicotiana tabacum) root tips preserved by high-pressure freezing/freeze-substitution techniques to gain more precise information about the organization of the ER in such cells. The most notable findings are: the identification of a specialized form of ER, termed "nodal ER," which is found exclusively in columella cells; the demonstration that the bulk of the ER is organized in the form of a tubular network that is confined to a peripheral layer under the plasma membrane; and the discovery that this ER-rich peripheral region excludes Golgi stacks, vacuoles, and amyloplasts but not mitochondria. Nodal ER domains consist of an approximately 100-nm-diameter central rod composed of oblong subunits to which usually seven sheets of rough ER are attached along their margins. These domains form patches at the interface between the peripheral ER network and the ER-free central region of the cells, and they occupy defined positions within central and flanking columella cells. Over one-half of the nodal ER domains are located along the outer tangential walls of the flanking cells. Cytochalasin D and latrunculin A cause an increase in size and a decrease in numbers of nodal ER domains. We postulate that the nodal ER membranes locally modulate the gravisensing signals produced by the sedimenting amyloplasts, and that the confinement of all ER membranes to the cell periphery serves to enhance the sedimentability of the amyloplasts in the central region of columella cells.
Scaling of Harmonic Oscillator Eigenfunctions and Their Nodal Sets Around the Caustic
NASA Astrophysics Data System (ADS)
Hanin, Boris; Zelditch, Steve; Zhou, Peng
We study the scaling asymptotics of the eigenspace projection kernels Π_{hbar, E}(x,y) of the isotropic Harmonic Oscillator {hat{H}_{hbar} = - hbar^2 Δ +|x|^2} of eigenvalue {E = hbar(N + d/2)} in the semi-classical limit {hbar to 0} . The principal result is an explicit formula for the scaling asymptotics of Π_{hbar, E}(x,y) for x, y in a {hbar^{2/3}} neighborhood of the caustic C_E as {hbar → 0.} The scaling asymptotics are applied to the distribution of nodal sets of Gaussian random eigenfunctions around the caustic as {hbar to 0} . In previous work we proved that the density of zeros of Gaussian random eigenfunctions of {hat{H}_{hbar}} have different orders in the Planck constant {hbar} in the allowed and forbidden regions: In the allowed region the density is of order {hbar^{-1}} while it is {hbar^{-1/2}} in the forbidden region. Our main result on nodal sets is that the density of zeros is of order {hbar^{-2/3}} in an {hbar^{2/3}} -tube around the caustic. This tube radius is the `critical radius'. For annuli of larger inner and outer radii {hbar^{α}} with {0 < α < 2/3} we obtain density results that interpolate between this critical radius result and our prior ones in the allowed and forbidden region. We also show that the Hausdorff ( d-2)-dimensional measure of the intersection of the nodal set with the caustic is of order {hbar^{- 2/3}}.
On the Nodal Lines of Eisenstein Series on Schottky Surfaces
NASA Astrophysics Data System (ADS)
Jakobson, Dmitry; Naud, Frédéric
On convex co-compact hyperbolic surfaces {X=Γ backslash H2}, we investigate the behavior of nodal curves of real valued Eisenstein series {F_λ(z,ξ)}, where {λ} is the spectral parameter, {ξ} the direction at infinity. Eisenstein series are (non-{L^2}) eigenfunctions of the Laplacian {Δ_X} satisfying {Δ_X F_λ=(1/4+λ^2)F_λ}. As {λ} goes to infinity (the high energy limit), we show that, for generic {ξ}, the number of intersections of nodal lines with any compact segment of geodesic grows like {λ}, up to multiplicative constants. Applications to the number of nodal domains inside the convex core of the surface are then derived.
Spin-Orbit Nodal Semimetals in the Layer Groups
NASA Astrophysics Data System (ADS)
Wieder, Benjamin; Kim, Youngkuk; Kane, Charles
Recent interest in point and line node semimetals has lead to the proposal and discovery of these phenomena in numerous systems. Frequently, though, these nodal systems are described in terms of individual properties reliant on specific space group intricacies or band-tuning conditions. Restricting ourselves to cases with strong spin-orbit interaction, we develop a more general framework which captures existing systems and predicts new examples of nodal materials. In many previously proposed systems, the three-dimensional nature of the space group has obscured key generalities. Therefore, we show how within our framework one can predict and characterize a diverse set of nodal phenomena even in two-dimensional systems constructed of three-dimensional sites, known as the ``Layer Groups''. Introducing a set of simple models, we characterize the allowed semimetallic structures in the layer groups and draw connections to analogous three-dimensional systems.
A computational study of nodal-based tetrahedral element behavior.
Gullerud, Arne S.
This report explores the behavior of nodal-based tetrahedral elements on six sample problems, and compares their solution to that of a corresponding hexahedral mesh. The problems demonstrate that while certain aspects of the solution field for the nodal-based tetrahedrons provide good quality results, the pressure field tends to be of poor quality. Results appear to be strongly affected by the connectivity of the tetrahedral elements. Simulations that rely on the pressure field, such as those which use material models that are dependent on the pressure (e.g. equation-of-state models), can generate erroneous results. Remeshing can also be strongly affected by these issues. The nodal-based test elements as they currently stand need to be used with caution to ensure that their numerical deficiencies do not adversely affect critical values of interest.
... version of this page please turn Javascript on. Heart Failure What is Heart Failure? In heart failure, the heart cannot pump enough ... failure often experience tiredness and shortness of breath. Heart Failure is Serious Heart failure is a serious and ...
A transient, quadratic nodal method for triangular-Z geometry
DeLorey, T.F.
Many systematically-derived nodal methods have been developed for Cartesian geometry due to the extensive interest in Light Water Reactors. These methods typically model the transverse-integrated flux as either an analytic or low order polynomial function of position within the node. Recently, quadratic nodal methods have been developed for R-Z and hexagonal geometry. A static and transient quadratic nodal method is developed for triangular-Z geometry. This development is particularly challenging because the quadratic expansion in each node must be performed between the node faces and the triangular points. As a consequence, in the 2-D plane, the flux and current at the points of the triangles must be treated. Quadratic nodal equations are solved using a non-linear iteration scheme, which utilizes the corrected, mesh-centered finite difference equations, and forces these equations to match the quadratic equations by computing discontinuity factors during the solution. Transient nodal equations are solved using the improved quasi-static method, which has been shown to be a very efficient solution method for transient problems. Several static problems are used to compare the quadratic nodal method to the Coarse Mesh Finite Difference (CMFD) method. The quadratic method is shown to give more accurate node-averaged fluxes. However, it appears that the method has difficulty predicting node leakages near reactor boundaries and severe material interfaces. The consequence is that the eigenvalue may be poorly predicted for certain reactor configurations. The transient methods are tested using a simple analytic test problem, a heterogeneous heavy water reactor benchmark problem, and three thermal hydraulic test problems. Results indicate that the transient methods have been implemented correctly.
Chiral Spin-Orbital Liquids with Nodal Lines
NASA Astrophysics Data System (ADS)
Natori, W. M. H.; Andrade, E. C.; Miranda, E.; Pereira, R. G.
Strongly correlated materials with strong spin-orbit coupling hold promise for realizing topological phases with fractionalized excitations. Here, we propose a chiral spin-orbital liquid as a stable phase of a realistic model for heavy-element double perovskites. This spin liquid state has Majorana fermion excitations with a gapless spectrum characterized by nodal lines along the edges of the Brillouin zone. We show that the nodal lines are topological defects of a non-Abelian Berry connection and that the system exhibits dispersing surface states. We discuss some experimental signatures of this state and compare them with properties of the spin liquid candidate Ba2YMoO6.
Nodal metastases in thyroid cancer: prognostic implications and management.
Wang, Laura Y; Ganly, Ian
The significance of cervical lymph node metastases in differentiated thyroid cancer has been controversial and continues to evolve. Current staging systems consider nodal metastases to confer a poorer prognosis, particularly in older patients. Increasingly, the literature suggests that characteristics of the metastatic lymph nodes such as size and number are also prognostic. There is a growing trend toward less aggressive treatment of low-volume nodal disease. The aim of this review is to summarize the current literature and discuss prognostic and management implications of lymph node metastases in differentiated thyroid cancer.
Preoperative staging of nodal status in gastric cancer
Berlth, Felix; Chon, Seung-Hun; Chevallay, Mickael; Jung, Minoa Karin
An accurate preoperative staging of nodal status is crucial in gastric cancer, because it has a great impact on prognosis and therapeutic decision-making. Different staging methods have been evaluated for gastric cancer in order to predict nodal involvement. So far, no technique could meet the necessary requirements, which include a high detection rate of infiltrated lymph nodes and a low frequency of false-positive results. This article summarizes different staging methods used to assess lymph node status in patients with gastric cancer, evaluates the evidence, and proposes to establish new methods. PMID:28217758
Long period nodal motion of sun synchronous orbits
NASA Technical Reports Server (NTRS)
Duck, K. I.
An approximative model is formulated for assessing these perturbations that significantly affect long term modal motion of sun synchronous orbits. Computer simulations with several independent computer programs consider zonal and tesseral gravitational harmonics, third body gravitational disturbances induced by the sun and the moon, and atmospheric drag. A pendulum model consisting of evenzonal harmonics through order 4 and solar gravity dominated nodal motion approximation. This pendulum motion results from solar gravity inducing an inclination oscillation which couples into the nodal precession induced by the earth's oblateness. The pendulum model correlated well with simulations observed flight data.
Mapping basin-wide subaquatic slope failure susceptibility as a tool to assess regional seismic and tsunami hazards
NASA Astrophysics Data System (ADS)
Strasser, Michael; Hilbe, Michael; Anselmetti, Flavio S.
With increasing awareness of oceanic geohazards, submarine landslides are gaining wide attention because of their catastrophic impacts on both offshore infrastructures (e.g. pipelines, cables and platforms) and coastal areas (e.g. landslide-induced tsunamis). They also are of great interest because they can be directly related to primary trigger mechanisms including earthquakes, rapid sedimentation, gas release, glacial and tidal loading, wave action, or clathrate dissociation, many of which represent potential geohazards themselves. In active tectonic environments, for instance, subaquatic landslide deposits can be used to make inferences regarding the hazard derived from seismic activity. Enormous scientific and economic efforts are thus being undertaken to better determine and quantify causes and effects of natural hazards related to subaquatic landslides. In order to achieve this fundamental goal, the detailed study of past events, the assessment of their recurrence intervals and the quantitative reconstruction of magnitudes and intensities of both causal and subsequent processes and impacts are key requirements. Here we present data and results from a study using fjord-type Lake Lucerne in central Switzerland as a "model ocean" to test a new concept for the assessment of regional seismic and tsunami hazard by basin-wide mapping of critical slope stability conditions for subaquatic landslide initiation. Previously acquired high-resolution bathymetry and reflection seismic data as well as sedimentological and in situ geotechnical data, provide a comprehensive data base to investigate subaquatic landslides and related geohazards. Available data are implemented into a basin-wide slope model. In a Geographic Information System (GIS)-framework, a pseudo-static limit equilibrium infinite slope stability equation is solved for each model point representing reconstructed slope conditions at different times in the past, during which earthquake-triggered landslides
Intensity-Modulated Radiotherapy for Tumors of the Nasal Cavity and Paranasal Sinuses: Clinical Outcomes and Patterns of Failure
Wiegner, Ellen A.; Daly, Megan E.; Murphy, James D.; Abelson, Jonathan; Chapman, Chris H.; Chung, Melody; Yu, Yao; Colevas, A. Dimitrios; Kaplan, Michael J.; Fischbein, Nancy; Le, Quynh-Thu; Chang, Daniel T.
Purpose: To report outcomes in patients treated with intensity-modulated radiotherapy (IMRT) for tumors of the paranasal sinuses and nasal cavity (PNS/NC). Methods/Materials: Between June 2000 and December 2009, 52 patients with tumors of the PNS/NC underwent postoperative or definitive radiation with IMRT. Twenty-eight (54%) patients had squamous cell carcinoma (SCC). Twenty-nine patients (56%) received chemotherapy. The median follow-up was 26.6 months (range, 2.9-118.4) for all patients and 30.9 months for living patients. Results: Eighteen patients (35%) developed local-regional failure (LRF) at median time of 7.2 months. Thirteen local failures (25%) were observed, 12 in-field and 1 marginal. Six regional failures were observed, two in-field and four out-of-field. No patients treated with elective nodal radiation had nodal regional failure. Two-year local-regional control (LRC), in-field LRC, freedom from distant metastasis (FFDM), and overall survival (OS) were 64%, 74%, 71%, and 66% among all patients, respectively, and 43%, 61%, 61%, and 53% among patients with SCC, respectively. On multivariate analysis, SCC and >1 subsite involved had worse LRC (p = 0.0004 and p = 0.046, respectively) and OS (p = 0.003 and p = 0.046, respectively). Cribriform plate invasion (p = 0.005) and residual disease (p = 0.047) also had worse LRC. Acute toxicities included Grade {>=}3 mucositis in 19 patients (37%), and Grade 3 dermatitis in 8 patients (15%). Six patients had Grade {>=}3 late toxicity including one optic toxicity. Conclusions: IMRT for patients with PNS/NC tumors has good outcomes compared with historical series and is well tolerated. Patients with SCC have worse LRC and OS. LRF is the predominant pattern of failure.
Polymorphic nodal elements and their application in discontinuous Galerkin methods
NASA Astrophysics Data System (ADS)
Gassner, Gregor J.; Lörcher, Frieder; Munz, Claus-Dieter; Hesthaven, Jan S.
In this work, we discuss two different but related aspects of the development of efficient discontinuous Galerkin methods on hybrid element grids for the computational modeling of gas dynamics in complex geometries or with adapted grids. In the first part, a recursive construction of different nodal sets for hp finite elements is presented. They share the property that the nodes along the sides of the two-dimensional elements and along the edges of the three-dimensional elements are the Legendre-Gauss-Lobatto points. The different nodal elements are evaluated by computing the Lebesgue constants of the corresponding Vandermonde matrix. In the second part, these nodal elements are applied within the modal discontinuous Galerkin framework. We still use a modal based formulation, but introduce a nodal based integration technique to reduce computational cost in the spirit of pseudospectral methods. We illustrate the performance of the scheme on several large scale applications and discuss its use in a recently developed space-time expansion discontinuous Galerkin scheme.
PoroTomo Subtask 6.3 Nodal Seismometers Metadata
Lesley Parker
Metadata for the nodal seismometer array deployed at the POROTOMO's Natural Laboratory in Brady Hot Spring, Nevada during the March 2016 testing. Metadata includes location and timing for each instrument as well as file lists of data to be uploaded in a separate submission.
Nodal Structure and the Partitioning of Equivalence Classes
ERIC Educational Resources Information Center
Fields, Lanny; Watanabe-Rose, Mari
By definition, all of the stimuli in an equivalence class have to be functionally interchangeable with each other. The present experiment, however, demonstrated that this was not the case when using post-class-formation dual-option response transfer tests. With college students, two 4-node 6-member equivalence classes with nodal structures of…
The Penn State Nodal Expansion Transient Analysis Technique with thermal-hydraulic feedback
Borkowski, J.; Bandini, B.; Baratta, A. )
The nuclear engineering department of the Pennsylvania State University has under development a nodal neutron kinetics code. The PEnn State Nodal Expansion TRansient Analysis TEchnique (PENETRATE) performs two-group, three-dimensional nodal kinetics calculations using the nodal expansion method (NEM). The focus of this discussion is its performance in the solution of the Langenbuch-Maurer-Werner light water rector (LMW LWR) problem. This transient requires an accurate model of both control rod motion and coupled thermal-hydraulic feedback.
Functional mathematical model of dual pathway AV nodal conduction.
Climent, A M; Guillem, M S; Zhang, Y; Millet, J; Mazgalev, T N
Dual atrioventricular (AV) nodal pathway physiology is described as two different wave fronts that propagate from the atria to the His bundle: one with a longer effective refractory period [fast pathway (FP)] and a second with a shorter effective refractory period [slow pathway (SP)]. By using His electrogram alternance, we have developed a mathematical model of AV conduction that incorporates dual AV nodal pathway physiology. Experiments were performed on five rabbit atrial-AV nodal preparations to develop and test the presented model. His electrogram alternances from the inferior margin of the His bundle were used to identify fast and slow wave front propagations. The ability to predict AV conduction time and the interaction between FP and SP wave fronts have been analyzed during regular and irregular atrial rhythms (e.g., atrial fibrillation). In addition, the role of dual AV nodal pathway wave fronts in the generation of Wenckebach periodicities has been illustrated. Finally, AV node ablative modifications have been evaluated. The model accurately reproduced interactions between FP and SP during regular and irregular atrial pacing protocols. In all experiments, specificity and sensitivity higher than 85% were obtained in the prediction of the pathway responsible for conduction. It has been shown that, during atrial fibrillation, the SP ablation significantly increased the mean HH interval (204 ± 39 vs. 274 ± 50 ms, P < 0.05), whereas FP ablation did not produce significant slowing of ventricular rate. The presented mathematical model can help in understanding some of the intriguing AV node mechanisms and should be considered as a step forward in the studies of AV nodal conduction.
Classification of nodal stations in gastric cancer
Costamagna, Guido; Doglietto, Giovanni Battista; Alfieri, Sergio
The lymphatic drainage from the stomach is anatomically elaborate and it is very hard to predict the pattern of lymph node (LN) metastases from gastric cancer (GC). However, there are LN stations metastases that are more frequently observed depending on the tumor location. Furthermore, the incidence of metastasis to various regional LN stations depends on the depth of gastric-wall invasion. The Japanese Gastric Cancer Association (JGCA) classifies the regional LNs draining the stomach into 33 regional lymphatic stations. These are distinguished into three (N1–N3) groups with respect to the location of the primary tumor. The aim of this classification is to provide a common language for the clinical, surgical, and pathological description of GC. PMID:28217752
Effects of Out-of-Plane Disorder on the Nodal Quasiparticle and Superconducting Gap in Single-Layer Bi_2Sr_1.6Ln_0.4CuO_6 delta (Ln = La, Nd, Gd)
Hashimoto, M.
How out-of-plane disorder affects the electronic structure has been investigated for the single-layer cuprates Bi{sub 2}Sr{sub 1.6}Ln{sub 0.4}CuO{sub 6+{delta}} (Ln = La, Nd, Gd) by angle-resolved photoemission spectroscopy. We have observed that, with increasing disorder, while the Fermi surface shape and band dispersions are not affected, the quasi-particle width increases, the anti-nodal gap is enhanced and the superconducting gap in the nodal region is depressed. The results indicate that the superconductivity is significantly depressed by out-of-plane disorder through the enhancement of the anti-nodal gap and the depression of the superconducting gap in the nodal region.
Nodal metastasis and elective nodal level treatment in sinonasal small-cell and sinonasal undifferentiated carcinoma: a surveillance, epidemiology and end results analysis
Mitra, Nandita; Alonso-Basanta, Michelle; Adappa, Nithin D; Palmer, James N; O'Malley, Bert W; Rassekh, Christopher H; Chalian, Ara; Cohen, Roger B; Lin, Alexander
Objective: Risk of nodal involvement in patients with sinonasal small-cell carcinoma and sinonasal undifferentiated carcinoma (SNUC) has not been well defined because of their rarity. We describe a population-based assessment of specific nodal level involvement in this group of rare neuroectodermal tumours. Methods: The Surveillance, Epidemiology and End Results (SEER) database from 2004 to 2011 identified patients with SNUC and sinonasal small-cell carcinoma. Overall neck involvement and individual nodal level involvement at presentation were assessed, and comparison was made with a contemporaneous cohort of patients with a borderline clinically significant risk of nodal involvement and recurrence. Results: Of 141 patients, 31 (22%) had gross nodal involvement at presentation (range 14–33% by site and histology). Non-nasal, non-ethmoid site with SNUC histology has the highest rates of initial nodal involvement, whereas higher stage and size do not predict for higher nodal involvement rates. Bilateral Levels 2–3 for all sinonasal small cell; Levels 2–3 for nasal or ethmoid SNUC; and bilateral Levels 1–3 in non-nasal/non-ethmoid SNUC have the highest rates of involvement compared with a clinical reference standard. Conclusion: We found high rates of initial nodal involvement in all SNUC and sinonasal small-cell carcinoma. We found higher initial involvement of Levels 2 and 3 and in certain cases to the Level 1 nodal levels, hypothesizing benefit for elective treatment to those levels. Advances in knowledge: With small single-institution series reporting conflicting nodal involvement rates, our data support high rates of nodal presentation at diagnosis, hypothesizing benefit for elective nodal treatment in this cohort. PMID:26559439
Anomalous contagion and renormalization in networks with nodal mobility
NASA Astrophysics Data System (ADS)
Manrique, Pedro D.; Qi, Hong; Zheng, Minzhang; Xu, Chen; Hui, Pak Ming; Johnson, Neil F.
A common occurrence in everyday human activity is where people join, leave and possibly rejoin clusters of other individuals —whether this be online (e.g. social media communities) or in real space (e.g. popular meeting places such as cafes). In the steady state, the resulting interaction network would appear static over time if the identities of the nodes are ignored. Here we show that even in this static steady-state limit, a non-zero nodal mobility leads to a diverse set of outbreak profiles that is dramatically different from known forms, and yet matches well with recent real-world social outbreaks. We show how this complication of nodal mobility can be renormalized away for a particular class of networks.
Off-diagonal Jacobian support for Nodal BCs
Peterson, John W.; Andrs, David; Gaston, Derek R.; Permann, Cody J.; Slaughter, Andrew E.
In this brief note, we describe the implementation of o-diagonal Jacobian computations for nodal boundary conditions in the Multiphysics Object Oriented Simulation Environment (MOOSE) [1] framework. There are presently a number of applications [2{5] based on the MOOSE framework that solve complicated physical systems of partial dierential equations whose boundary conditions are often highly nonlinear. Accurately computing the on- and o-diagonal Jacobian and preconditioner entries associated to these constraints is crucial for enabling ecient numerical solvers in these applications. Two key ingredients are required for properly specifying the Jacobian contributions of nonlinear nodal boundary conditions in MOOSE and nite element codes in general: 1. The ability to zero out entire Jacobian matrix rows after \
Total Gross Tumor Volume Is an Independent Prognostic Factor in Patients Treated With Selective Nodal Irradiation for Stage I to III Small Cell Lung Cancer
Reymen, Bart; Van Loon, Judith; Baardwijk, Angela van; Wanders, Rinus; Borger, Jacques; Dingemans, Anne-Marie C.; Bootsma, Gerben; Pitz, Cordula; Lunde, Ragnar; Geraedts, Wiel; Lambin, Philippe; De Ruysscher, Dirk
Purpose: In non-small cell lung cancer, gross tumor volume (GTV) influences survival more than other risk factors. This could also apply to small cell lung cancer. Methods and Materials: Analysis of our prospective database with stage I to III SCLC patients referred for concurrent chemo radiation therapy. Standard treatment was 45 Gy in 1.5-Gy fractions twice daily concurrently with carboplatin-etoposide, followed by prophylactic cranial irradiation (PCI) in case of non-progression. Only fluorodeoxyglucose (FDG)-positron emission tomography (PET)-positive or pathologically proven nodal sites were included in the target volume. Total GTV consisted of post chemotherapy tumor volume and pre chemotherapy nodal volume. Survival was calculated from diagnosis (Kaplan-Meier ). Results: A total of 119 patients were included between May 2004 and June 2009. Median total GTV was 93 ± 152 cc (7.5-895 cc). Isolated elective nodal failure occurred in 2 patients (1.7%). Median follow-up was 38 months, median overall survival 20 months (95% confidence interval = 17.8-22.1 months), and 2-year survival 38.4%. In multivariate analysis, only total GTV (P=.026) and performance status (P=.016) significantly influenced survival. Conclusions: In this series of stage I to III small cell lung cancer patients treated with FDG-PET-based selective nodal irradiation total GTV is an independent risk factor for survival.
Nicot, Romain; Hottenstein, Molly; Raoul, Gwenael; Ferri, Joel; Horton, Michael; Tobias, John W.; Barton, Elisabeth; Gelé, Patrick; Sciote, James J.
Purpose Facial asymmetry is a common comorbid condition in patients with jaw deformation malocclusion. Heritability of malocclusion is advancing rapidly, but very little is known regarding genetic contributions to asymmetry. This study identifies differences in expression of key asymmetry-producing genes which are down regulated in facial asymmetry patients. Material and Methods Masseter muscle samples were collected during BSSO orthognathic surgery to correct skeletal-based malocclusion. Patients were classified as Class II or III and open or deep bite malocclusion with or without facial asymmetry. Muscle samples were analyzed for gene expression differences on Affymetrix HT2.0 microarray global expression chips. Results Overall gene expression was different for asymmetric patients compared to other malocclusion classifications by principal component analysis (P<0.05). We identified differences in the nodal signaling pathway (NSP) which promotes development of mesoderm and endoderm and left-right patterning during embryogenesis. Nodal and Lefty expression was 1.39–1.84 fold greater (P<3.41×10−5) whereas integral membrane Nodal-modulators Nomo1,2,3 were −5.63 to −5.81 (P<3.05×10−4) less in asymmetry subjects. Fold differences among intracellular pathway members were negative in the range of −7.02 to −2.47 (P<0.003). Finally Pitx2, a upstream effector of Nodal known to influence the size of type II skeletal muscle fibers was also significantly decreased in facial asymmetry (P<0.05). Conclusions When facial asymmetry is part of skeletal malocclusion there are decreases of NSP genes in masseter muscle. This data suggests that the NSP is down regulated to help promote development of asymmetry. Pitx2 expression differences also contributed to both skeletal and muscle development in this condition. PMID:25364968
Topological phase transitions in line-nodal superconductors
NASA Astrophysics Data System (ADS)
Han, SangEun; Cho, Gil Young; Moon, Eun-Gook
Fathoming interplay between symmetry and topology of many-electron wave functions has deepened our understanding of quantum many-body systems, particularly after the discovery of topological insulators. Topology of electron wave functions often enforces and protects emergent gapless excitation, and symmetry is intrinsically tied to the topological protection of the excitations. Namely, unless the symmetry is broken, the topological nature of the excitations is intact. We show intriguing phenomena of interplay between symmetry and topology in three-dimensional topological phase transitions associated with line-nodal superconductors. More specifically, we discover an exotic universality class out of topological line-nodal superconductors. The order parameter of broken symmetries is strongly correlated with underlying line-nodal fermions, and this gives rise to a large anomalous dimension in sharp contrast to that of the Landau-Ginzburg theory. Remarkably, hyperscaling violation and emergent relativistic scaling appear in spite of the presence of nonrelativistic fermionic excitation. We also propose characteristic experimental signatures around the phase transitions, for example, a linear phase boundary in a temperature-tuning parameter phase diagram, and discuss the implication of recent experiments in pnictides and heavy-fermion systems.
Anomalous scaling of the penetration depth in nodal superconductors
NASA Astrophysics Data System (ADS)
She, Jian-Huang; Lawler, Michael J.; Kim, Eun-Ah
Recent findings of anomalous superlinear scaling of low-temperature (T ) penetration depth (PD) in several nodal superconductors near putative quantum critical points suggest that the low-temperature PD can be a useful probe of quantum critical fluctuations in a superconductor. On the other hand, cuprates, which are poster child nodal superconductors, have not shown any such anomalous scaling of PD, despite growing evidence of quantum critical points (QCP). Then it is natural to ask when and how can quantum critical fluctuations cause anomalous scaling of PD? Carrying out the renormalization group calculation for the problem of two-dimensional superconductors with point nodes, we show that quantum critical fluctuations associated with a point group symmetry reduction result in nonuniversal logarithmic corrections to the T dependence of the PD. The resulting apparent power law depends on the bare velocity anisotropy ratio. We then compare our results to data sets from two distinct nodal superconductors: YBa2Cu3O6.95 and CeCoIn5. Considering all symmetry-lowering possibilities of the point group of interest, C4 v, we find our results to be remarkably consistent with YBa2Cu3O6.95 being near a vertical nematic QCP and CeCoIn5 being near a diagonal nematic QCP. Our results motivate a search for diagonal nematic fluctuations in CeCoIn5.
A nodal domain theorem for integrable billiards in two dimensions
Samajdar, Rhine; Jain, Sudhir R.
Eigenfunctions of integrable planar billiards are studied — in particular, the number of nodal domains, ν of the eigenfunctions with Dirichlet boundary conditions are considered. The billiards for which the time-independent Schrödinger equation (Helmholtz equation) is separable admit trivial expressions for the number of domains. Here, we discover that for all separable and non-separable integrable billiards, ν satisfies certain difference equations. This has been possible because the eigenfunctions can be classified in families labelled by the same value of mmodkn, given a particular k, for a set of quantum numbers, m,n. Further, we observe that the patterns in a family are similar and the algebraic representation of the geometrical nodal patterns is found. Instances of this representation are explained in detail to understand the beauty of the patterns. This paper therefore presents a mathematical connection between integrable systems and difference equations. - Highlights: • We find that the number of nodal domains of eigenfunctions of integrable, planar billiards satisfy a class of difference equations. • The eigenfunctions labelled by quantum numbers (m,n) can be classified in terms of mmodkn. • A theorem is presented, realising algebraic representations of geometrical patterns exhibited by the domains. • This work presents a connection between integrable systems and difference equations.
Histogenesis of metaplastic breast carcinoma and axillary nodal metastases.
Osako, Tomo; Horii, Rie; Ogiya, Akiko; Iijima, Kotaro; Iwase, Takuji; Akiyama, Futoshi
A 40-year-old breast-feeding woman presented with left breast swelling. On physical examination a 7 cm mass was found in the breast. Because biopsy demonstrated malignant tissue, mastectomy with axillary nodal dissection was performed. Pathological findings were consistent with metaplastic breast carcinoma with nodal metastases. The primary tumor consisted of three types of invasion: ductal, squamous, and sarcomatous. Furthermore, three morphological transitions were observed: ductal-squamous, ductal-sarcomatous, and squamous-sarcomatous. Ductal-squamous (12/18 microscopy slides) and squamous-sarcomatous transitions (10/18) were more commonly observed than ductal-sarcomatous transition (3/18). Furthermore, immunohistochemistry showed loss of epithelial marker (cytokeratin) and acquisition of mesenchymal markers (vimentin and alpha-smooth muscle actin) in the sarcomatous component. These findings suggested that epithelial-mesenchymal transition had occurred in the tumor and that two pathways, ductal-squamous-sarcomatous and ductal-sarcomatous transition, were involved in progression of metaplastic breast carcinoma. The main pathway appeared to be ductal-squamous-sarcomatous transition. Regarding the nodal metastases, of 13 positive nodes, ductal, squamous, and sarcomatous components were observed in 13, seven, and two nodes, respectively. Moreover, as in the primary tumor, ductal-squamous and squamous-sarcomatous transitions were observed. This suggested that the ductal component metastasized to the nodes and that epithelial-mesenchymal transition subsequently occurred within the nodes.
Squamous Cell Carcinoma of the Anal Canal: Patterns and Predictors of Failure and Implications for Intensity-Modulated Radiation Treatment Planning
Wright, Jean L.; Patil, Sujata M.; Temple, Larissa K.F.; Minsky, Bruce D.; Saltz, Leonard B.; Goodman, Karyn A.
Purpose: Intensity-modulated radiation treatment (IMRT) is increasingly used in the treatment of squamous cell carcinoma of the anal canal (SCCAC). Prevention of locoregional failure (LRF) using IMRT requires appropriate clinical target volume (CTV) definition. To better define the CTV for IMRT, we evaluated patterns and predictors of LRF in SCCAC patients given conventional radiation treatment. Methods and Materials: We reviewed records of 180 SCCAC patients treated with conventional radiation with or without chemotherapy at our institution between January 1990 and March 2007. All patients received radiation; the median primary tumor dose was 45 Gy. A total of 173 patients also received mitomycin-based chemotherapy. Results: Median follow-up was 40 months. Actuarial 3-year colostomy-free survival was 89% and overall survival (OS) 88%. Actuarial 3-year LRF was 23%. A total of 45 patients had LRF, with 35 (78%) occurring locally in the primary site (25 local only, 10 local and regional); however, 20 (44%) had regional components of failure within the pelvis or inguinal nodes (10 regional only, 10 local and regional). Cumulative sites of LRF (patients may have one or more site of failure) were as follows: primary, 35; inguinal, 8; external perianal, 5; common iliac, 4; presacral, 3; distal rectum, 2; external iliac, 2; and internal iliac, 2. All patients with common iliac failure had cT3 or N+ disease. Conclusions: The observed patterns of failure support inclusion of the inguinal and all pelvic nodal groups in the CTV for IMRT. In patients with advanced tumor or nodal stage, common iliac nodes should also be included in the CTV.
Predictors of failure of awake regional anesthesia for neonatal hernia repair: data from the General Anesthesia compared to Spinal anesthesia (GAS) study: comparing apnoea and neurodevelopmental outcomes
Frawley, Geoff; Bell, Graham; Disma, Nicola; Withington, Davinia E.; de Graaff, Jurgen C.; Morton, Neil S.; McCann, Mary Ellen; Arnup, Sarah J.; Bagshaw, Oliver; Wolfler, Andrea; Bellinger, David; Davidson, Andrew J.
Background Awake regional anesthesia (RA) is a viable alternative to general anesthesia (GA) for infants undergoing lower abdominal surgery. Benefits include lower incidence of postoperative apnea and avoidance of anesthetic agents that may increase neuroapoptosis and worsen neurocognitive outcomes. The General Anesthesia compared to Spinal anesthesia (GAS) study compares neurodevelopmental outcomes following awake RA or GA in otherwise healthy infants. Our aim was to describe success and failure rates of RA in this study and report factors associated with failure. Methods This was a nested cohort study within a prospective randomized, controlled, observer blind, equivalence trial. Seven hundred twenty two infants ≤ 60 weeks postmenstrual age, scheduled for herniorrhaphy under anesthesia were randomly assigned to receive RA (spinal, caudal epidural or combined spinal caudal anesthetic) or GA with sevoflurane. The data of 339 infants, where spinal or combined spinal caudal anesthetic was attempted, was analyzed. Possible predictors of failure were assessed including: patient factors, technique, experience of site and anesthetist and type of local anesthetic. Results RA was sufficient for the completion of surgery in 83.2% of patients. Spinal anesthesia was successful in 86.9% of cases and combined spinal caudal anesthetic in 76.1%. Thirty four patients required conversion to GA and an additional 23 (6.8%) required brief sedation. Bloody tap on the first attempt at lumbar puncture was the only risk factor significantly associated with block failure (OR = 2.46). Conclusions The failure rate of spinal anesthesia was low. Variability in application of combined spinal caudal anesthetic limited attempts to compare the success of this technique to spinal alone. PMID:26001028
Endogenous Nodal promotes melanoma undergoing epithelial-mesenchymal transition via Snail and Slug in vitro and in vivo
Guo, Qiang; Ning, Fen; Fang, Rui; Wang, Hong-Sheng; Zhang, Ge; Quan, Mei-Yu; Cai, Shao-Hui; Du, Jun
Nodal, an important embryonic morphogen, has been reported to modulate tumorigenesis. Epithelial-mesenchymal transition (EMT) plays an important role in cancer metastasis. We have previously reported that recombinant Nodal treatment can promote melanoma undergoing EMT, but the effects of endogenous Nodal on EMT are still unknown. Here we generated both Nodal-overexpression and -knockdown stable cell lines to investigate the in vitro and in vivo characteristics of Nodal-induced EMT in murine melanoma cells. Nodal-overexpression cells displayed increased migration ability, accompanied by typical phenotype changes of EMT. In contrast, Nodal-knockdown stable cells repressed the EMT phenotype as well as reduced cell motility. Results of animal experiments confirmed that overexpression of Nodal can promote the metastasis of melanoma tumor in vivo. Mechanistically, we found that Nodal-induced expression of Snail and Slug involves its activation of ALK/Smads and PI3k/AKT pathways, which is an important process in the Nodal-induced EMT. However, we also found that the EMT phenotype was not completely inhibited by blocking the paracrine activity of Nodal in Nodal overexpression cell line suggesting the presence of additional mechanism(s) in the Nodal-induced EMT. This study provides a better understanding of Nodal function in melanoma, and suggests targeting Nodal as a potential strategy for melanoma therapey. PMID:26269769
Benign nodal lesions mimicking metastases from pediatric renal neoplasms: a report of the National Wilms' Tumor Study Pathology Center.
Weeks, D A; Beckwith, J B; Mierau, G W
Regional lymph node status is a key factor in the staging of pediatric renal tumors on the National Wilms' Tumor Study (NWTS). A review of cases entered on the NWTS has uncovered a number of cases where benign lymph node findings were mistaken for metastases. Most frequently, this was due to the presence of complexes of epithelial cells and Tamm-Horsfall protein within nodal sinuses. The epithelial cells were derived from damaged nephrons, usually resulting from obstruction by tumor. Another epithelial pseudometastic lesion, intranodal squamous epithelial cells, was found to originate from metaplastic calyceal urothelium. Benign mesothelial or coelomic inclusions similar to those previously described in pelvic and periaortic lymph nodes of adult females were found in nodes of four patients, including two boys, who are, to our knowledge, the first to be described with this finding. Other sources of confusion included protrusion of lymphoid follicles or germinal centers into nodal sinuses, thick endothelial cells of postcapillary venules mimicking epithelial tubules, nodal megakaryocytes resembling anaplastic nuclear changes, and histiocytic granulomas. Immunocytochemical methods were useful in evaluating some of these phenomena. Recognition of these pseudometastatic lesions is essential in order to avoid unnecessary and potentially hazardous therapeutic intensification.
Post-radiotherapy neck dissection improves control at non-regional disease sites after definitive chemoradiation for squamous cell carcinoma of the head and neck
Ranck, Mark C.; Abundo, Rainier; Jefferson, Gina; Kolokythas, Antonia; Wenig, Barry L.; Weichselbaum, Ralph R.; Spiotto, Michael T.
Importance After chemoradiation for head and neck cancer, over ninety percent of patients who achieved a complete response by imaging were regionally controlled without post-radiotherapy neck dissections (PRND). Since several groups have reported that lymph node involvement also predicted failure at both primary and distant sites, it remains unclear the extent to which PRND impacts non-regional sites of disease. Objective Here, we evaluated how PRND impacted local and distant control in patients who achieved a clinical complete response. Design We retrospectively reviewed patients treated for stage III/IV disease with definitive chemoradiation between 1990 to 2012. Setting University of Illinois at Chicago. Participants 287 patients were treated with definitive CRT, of whom seventy-four underwent PRND. Median follow up was 25.4 months. Interventions Chemoradiation followed by lymph node dissection or observation. Main Outcomes and Measures Endpoints evaluated included local control (LC), regional control (RC), freedom from distant metastasis (FFDM), progression free survival (PFS) and overall survival (OS) using first-failure analysis. Results Patients with advanced nodal disease (≥N2b; n=176) had improved PFS (74.6% vs. 39.1%; P<.001) while patients with lesser nodal disease had similar PFS. For patients with advanced nodal disease, PRND improved 2-year LC (85.5 vs. 53.5%; p<.001), locoregional control with PRND (78.9% vs. 45.7%; P<.001), FFDM (79.5% vs. 67.5%%; P=.03) and OS (84.5% vs. 61.7%; P=.004) but not RC (96.9% vs. 90.1%; P=.21) The benefit in LC (87.4% vs. 66.2%; P=.02) and PFS (80.7% vs. 53.4%; P=.01) persisted for those with negative post-treatment imaging who underwent PRND. On univariate analysis, PRND, alcohol use, nodal stage and chemoradiation significantly impacted 2 year LC and/or PFS. On multivariate analysis, PRND remained strongly prognostic for 2 year LC (HR 0.22; P=.0007) and PFS (HR 0.42; P=.002). Conclusions and Relevance PRND improved
Extra-nodal Diffuse Large B-cell Lymphoma (Germinal Center Type) Manifesting as Non-healing Extraction Socket
Basavarajappa, Manjunath Anekonda; Pathan, Sana; Raheem, Ahmed Mujib Bangalore; Godavarthy, Divyasri
Lymphomas occurring in the oral cavity are rare. They account only for about 2% of extra-nodal sites. Most of the lymphomas occur in the lymph nodes and in the oral cavity, the most commonly affected region is the Waldeyer's ring. Its occurrence in the mandibular gingiva is rare. Here, we describe a case of Diffuse Large B-cell Lymphoma manifested as a non-healing extraction socket in the mandibular right posterior region in a 62-year-old male patient. PMID:27656575
Topological Dirac nodal lines and surface charges in fcc alkaline earth metals.
Hirayama, Motoaki; Okugawa, Ryo; Miyake, Takashi; Murakami, Shuichi
In nodal-line semimetals, the gaps close along loops in k space, which are not at high-symmetry points. Typical mechanisms for the emergence of nodal lines involve mirror symmetry and the π Berry phase. Here we show via ab initio calculations that fcc calcium (Ca), strontium (Sr) and ytterbium (Yb) have topological nodal lines with the π Berry phase near the Fermi level, when spin-orbit interaction is neglected. In particular, Ca becomes a nodal-line semimetal at high pressure. Owing to nodal lines, the Zak phase becomes either π or 0, depending on the wavevector k, and the π Zak phase leads to surface polarization charge. Carriers eventually screen it, leaving behind large surface dipoles. In materials with nodal lines, both the large surface polarization charge and the emergent drumhead surface states enhance Rashba splitting when heavy adatoms are present, as we have shown to occur in Bi/Sr(111) and in Bi/Ag(111).
Topological Dirac nodal lines and surface charges in fcc alkaline earth metals
NASA Astrophysics Data System (ADS)
Hirayama, Motoaki; Okugawa, Ryo; Miyake, Takashi; Murakami, Shuichi
In nodal-line semimetals, the gaps close along loops in k space, which are not at high-symmetry points. Typical mechanisms for the emergence of nodal lines involve mirror symmetry and the π Berry phase. Here we show via ab initio calculations that fcc calcium (Ca), strontium (Sr) and ytterbium (Yb) have topological nodal lines with the π Berry phase near the Fermi level, when spin-orbit interaction is neglected. In particular, Ca becomes a nodal-line semimetal at high pressure. Owing to nodal lines, the Zak phase becomes either π or 0, depending on the wavevector k, and the π Zak phase leads to surface polarization charge. Carriers eventually screen it, leaving behind large surface dipoles. In materials with nodal lines, both the large surface polarization charge and the emergent drumhead surface states enhance Rashba splitting when heavy adatoms are present, as we have shown to occur in Bi/Sr(111) and in Bi/Ag(111).
Topological nodal line semimetals with and without spin-orbital coupling
NASA Astrophysics Data System (ADS)
Fang, Chen; Chen, Yige; Kee, Hae-Young; Fu, Liang
We theoretically study three-dimensional topological semimetals (TSMs) with nodal lines protected by crystalline symmetries. Compared to TSMs with point nodes, e.g., Weyl semimetals and Dirac semimetals, where the conduction and the valence bands touch at discrete points, in these TSMs the two bands cross at closed lines in the Brillouin zone. We propose two different classes of symmetry protected nodal lines in the absence and in the presence of spin-orbital coupling (SOC), respectively. In the former, we discuss nodal lines that are protected by a combination of inversion symmetry and time-reversal symmetry, yet, unlike previously studied nodal lines in the same symmetry class, each nodal line has a Z2 monopole charge and can only be created (annihilated) in pairs. In the second class, with SOC, we show that a nonsymmorphic symmetry (screw axis) protects a four-band crossing nodal line in systems having both inversion and time-reversal symmetries.
Elsevier Trophoblast Research Award lecture: The multifaceted role of Nodal signaling during mammalian reproduction.
Park, C B; Dufort, D
Nodal, a secreted signaling protein in the transforming growth factor-beta (TGF-β) superfamily, has established roles in vertebrate development. However, components of the Nodal signaling pathway are also expressed at the maternal-fetal interface and have been implicated in many processes of mammalian reproduction. Emerging evidence indicates that Nodal and its extracellular inhibitor Lefty are expressed in the uterus and complex interactions between the two proteins mediate menstruation, decidualization and embryo implantation. Furthermore, several studies have shown that Nodal from both fetal and maternal sources may regulate trophoblast cell fate and facilitate placentation as both embryonic and uterine-specific Nodal knockout mouse strains exhibit disrupted placenta morphology. Here we review the established and prospective roles of Nodal signaling in facilitating successful pregnancy, including recent evidence supporting a potential link to parturition and preterm birth.
A Nodal-independent and tissue-intrinsic mechanism controls heart-looping chirality
NASA Astrophysics Data System (ADS)
Noël, Emily S.; Verhoeven, Manon; Lagendijk, Anne Karine; Tessadori, Federico; Smith, Kelly; Choorapoikayil, Suma; den Hertog, Jeroen; Bakkers, Jeroen
Breaking left-right symmetry in bilateria is a major event during embryo development that is required for asymmetric organ position, directional organ looping and lateralized organ function in the adult. Asymmetric expression of Nodal-related genes is hypothesized to be the driving force behind regulation of organ laterality. Here we identify a Nodal-independent mechanism that drives asymmetric heart looping in zebrafish embryos. In a unique mutant defective for the Nodal-related southpaw gene, preferential dextral looping in the heart is maintained, whereas gut and brain asymmetries are randomized. As genetic and pharmacological inhibition of Nodal signalling does not abolish heart asymmetry, a yet undiscovered mechanism controls heart chirality. This mechanism is tissue intrinsic, as explanted hearts maintain ex vivo retain chiral looping behaviour and require actin polymerization and myosin II activity. We find that Nodal signalling regulates actin gene expression, supporting a model in which Nodal signalling amplifies this tissue-intrinsic mechanism of heart looping.
Economic impact assessment from the use of a mobile app for the self-management of heart diseases by patients with heart failure in a Spanish region.
Cano Martín, José Antonio; Martínez-Pérez, Borja; de la Torre-Díez, Isabel; López-Coronado, Miguel
Currently, cardiovascular diseases are the deadliest diseases with a total of 17 million deaths worldwide. Hence, they are the focus of many mobile applications for smartphones and tablets. This paper will assess the ex-ante economic impact as well as will determine the cost-effectiveness analysis that the use of one of this app, CardioManager, by patients with heart failure will have in a Spanish community, Castile and Leon. For this, a cost-effectiveness analysis using the hidden Markov model were performed in a hypothetical cohort of patients diagnosed with heart failure, based on the information of epidemiological parameters and the costs derived from the management and care of heart failure patients by the Public Health Care System of Castile and Leon. The costs of patient care were estimated from the perspective of the Ministry of Health of Spain using a discount rate of 3 %. Finally, an estimation of the ex-ante impact that would suppose the introduction of CardioManager in the Health Care System is performed. It is concluded that the introduction of CardioManager may generate a 33 % reduction in the cost of management and treatment of the disease. This means that CardioManager may be able to save more than 9,000 € per patient to the local Health Care System of Castile and Leon, which can be translated in a saving of 0.31 % of the total health expenditure of the region.
Approximate Schur complement preconditioning of the lowest order nodal discretizations
Moulton, J.D.; Ascher, U.M.; Morel, J.E.
Particular classes of nodal methods and mixed hybrid finite element methods lead to equivalent, robust and accurate discretizations of 2nd order elliptic PDEs. However, widespread popularity of these discretizations has been hindered by the awkward linear systems which result. The present work exploits this awkwardness, which provides a natural partitioning of the linear system, by defining two optimal preconditioners based on approximate Schur complements. Central to the optimal performance of these preconditioners is their sparsity structure which is compatible with Dendy`s black box multigrid code.
Topological insulating phases from two-dimensional nodal loop semimetals
NASA Astrophysics Data System (ADS)
Li, Linhu; Araújo, Miguel A. N.
Starting from a minimal model for a two-dimensional nodal loop semimetal, we study the effect of chiral mass gap terms. The resulting Dirac loop anomalous Hall insulator's Chern number is the phase-winding number of the mass gap terms on the loop. We provide simple lattice models, analyze the topological phases, and generalize a previous index characterizing topological transitions. The responses of the Dirac loop anomalous Hall and quantum spin Hall insulators to a magnetic field's vector potential are also studied both in weak- and strong-field regimes, as well as the edge states in a ribbon geometry.
Radiotherapy studies and extra-nodal non-Hodgkin lymphomas, progress and challenges.
Specht, L
Extra-nodal lymphomas may arise in any organ, and different histological subtypes occur in distinct patterns. Prognosis and treatment depend not only on the histological subtype and disease extent, but also on the particular involved extra-nodal organ. The clinical course and response to treatment for the more common extra-nodal organs, e.g. stomach, Waldeyer's ring, skin and brain, are fairly well known and show significant variation. A few randomised trials have been carried out testing the role of radiotherapy in these lymphomas. However, for most extra-nodal lymphomas, randomised trials have not been carried out, and treatment decisions are made on small patient series and extrapolations from nodal lymphomas. Hopefully, wide international collaboration will make controlled clinical trials possible in the less common extra-nodal lymphomas. Modern highly conformal radiotherapy allows better coverage of extra-nodal lymphomatous involvement with better sparing of normal tissues. The necessary radiation doses and volumes need to be defined for the different extra-nodal lymphoma entities. The challenge is to optimise the use of radiotherapy in the modern multimodality treatment of extra-nodal lymphomas.
Magnon nodal-line semimetals and drumhead surface states in anisotropic pyrochlore ferromagnets
NASA Astrophysics Data System (ADS)
Mook, Alexander; Henk, Jürgen; Mertig, Ingrid
We introduce a type of topological magnon matter: the magnonic pendant to electronic nodal-line semimetals. Magnon spectra of anisotropic pyrochlore ferromagnets feature twofold degeneracies of magnon bands along a closed loop in reciprocal space. These magnon nodal lines are topologically protected by the coexistence of inversion and time-reversal symmetry; they require the absence of spin-orbit interaction (no Dzyaloshinskii-Moriya interaction). We calculate the topological invariants of the nodal lines and show that details of the associated magnon drumhead surface states depend strongly on the termination of the surface. Magnon nodal-line semimetals complete the family of topological magnons in three-dimensional ferromagnetic materials.
Nodal line optimization and its application to violin top plate design
NASA Astrophysics Data System (ADS)
Yu, Yonggyun; Jang, In Gwun; Kim, In Kyum; Kwak, Byung Man
In the literature, most problems of structural vibration have been formulated to adjust a specific natural frequency: for example, to maximize the first natural frequency. In musical instruments like a violin; however, mode shapes are equally important because they are related to sound quality in the way that natural frequencies are related to the octave. The shapes of nodal lines, which represent the natural mode shapes, are generally known to have a unique feature for good violins. Among the few studies on mode shape optimization, one typical study addresses the optimization of nodal point location for reducing vibration in a one-dimensional beam structure. However, nodal line optimization, which is required in violin plate design, has not yet been considered. In this paper, the central idea of controlling the shape of the nodal lines is proposed and then applied to violin top plate design. Finite element model for a violin top plate was constructed using shell elements. Then, optimization was performed to minimize the square sum of the displacement of selected nodes located along the target nodal lines by varying the thicknesses of the top plate. We conducted nodal line optimization for the second and the fifth modes together at the same time, and the results showed that the nodal lines obtained match well with the target nodal lines. The information on plate thickness distribution from nodal line optimization would be valuable for tailored trimming of a violin top plate for the given performances.
Risk factors for tuberculosis treatment failure among pulmonary tuberculosis patients in four health regions of Burkina Faso, 2009: case control study
Sawadogo, Bernard; Tint, Khin San; Tshimanga, Mufuta; Kuonza, Lazarus; Ouedraogo, Laurent
Introduction In Burkina Faso, the tuberculosis (TB) treatment failure rate increased from 2.5% in 2000 to 8.3% in 2006. The risk factors for TB treatment failure in the country are not well known. The study aims to determine the risk factors for treatment failure among pulmonary tuberculosis patients in four health region of Burkina Faso and to recommend appropriate interventions. Methods A case control study was conducted among pulmonary TB patients who began TB treatment in 2009. A case was any patient who remained smear-positive at fifth month of TB treatment and a control was a patient who tested smear-negative at fifth month of treatment. A structured questionnaire was administered to one hundred cases and one hundred controls to collect information on exposure factors. Odds ratio were calculated using bivariate and multivariate analysis to determine the association between exposures and outcome. Results Multivariate analysis showed that independent risk factors for TB treatment failure were fail to take TB drugs for more than 14 consecutive days (OR = 18.53; 95% CI:4.56 - 75.22), sputum smear-positive at two months of treatment (OR = 11.52; 95%CI:5.18-25.60), existence of comorbidity (OR = 5.74; 95%CI:1.69-19.44), and use of traditional medicines or herbs (OR = 2.97; 95%CI:1.12-7.85). Conclusion Early identification of patients with the above risk factors for intense case management will improve TB treatment outcome. Patient with smear positive at 2ndnd month of treatment require more intense follow-up, and involving traditional healers who provide traditional medicines or herbs in the educational programme on TB are required. The national referral laboratory capacity needs to be strengthened to do drug susceptibility testing and routine drug monitoring on cases of non conversion at 2nd month of treatment. PMID:26327989
High-latitude oceanic variability associated with the 18.6-year nodal tide
NASA Technical Reports Server (NTRS)
Royer, Thomas C.
Water column temperature variations which indicate that the upper ocean is responding to 18.6-yr tidal forcing are presented. An enhanced high-latitude response to this forcing is predicted by equilibrium tide theory, and it should be most evident at latitudes poleward of about 50 deg. Critical information on regional climate variations might be found in the subsurface waters of the North Pacific and possibly other high-latitude oceans. The 18.6-yr nodal tidal cycle must be considered in circulation models of the ocean and atmosphere that examine time scales of decades or longer. Because the temperature range associated with the cycle is 0.5-1 C, short-term climate and biological populations could be affected.
The Cerberus/Dan-family protein Charon is a negative regulator of Nodal signaling during left-right patterning in zebrafish.
Hashimoto, Hisashi; Rebagliati, Michael; Ahmad, Nadira; Muraoka, Osamu; Kurokawa, Tadahide; Hibi, Masahiko; Suzuki, Tohru
We have isolated a novel gene, charon, that encodes a member of the Cerberus/Dan family of secreted factors. In zebrafish, Fugu and flounder, charon is expressed in regions embracing Kupffer's vesicle, which is considered to be the teleost fish equivalent to the region of the mouse definitive node that is required for left-right (L/R) patterning. Misexpression of Charon elicited phenotypes similar to those of mutant embryos defective in Nodal signaling or embryos overexpressing Antivin(Atv)/Lefty1, an inhibitor for Nodal and Activin. Charon also suppressed the dorsalizing activity of all three of the known zebrafish Nodal-related proteins (Cyclops, Squint and Southpaw), indicating that Charon can antagonize Nodal signaling. Because Southpaw functions in the L/R patterning of lateral plate mesoderm and the diencephalon, we asked whether Charon is involved in regulating L/R asymmetry. Inhibition of Charon's function by antisense morpholino oligonucleotides (MOs) led to a loss of L/R polarity, as evidenced by bilateral expression of the left side-specific genes in the lateral plate mesoderm (southpaw, cyclops, atv/lefty1, lefty2 and pitx2) and diencephalon (cyclops, atv/lefty1 and pitx2), and defects in early (heart jogging) and late (heart looping) asymmetric heart development, but did not disturb the notochord development or the atv/lefty1-mediated midline barrier function. MO-mediated inhibition of both Charon and Southpaw led to a reduction in or loss of the expression of the left side-specific genes, suggesting that Southpaw is epistatic to Charon in left-side formation. These data indicate that antagonistic interactions between Charon and Nodal (Southpaw), which take place in regions adjacent to Kupffer's vesicle, play an important role in L/R patterning in zebrafish.
Clinically Apparent Internal Mammary Nodal Metastasis in Patients With Advanced Breast Cancer: Incidence and Local Control
Zhang Yujing; Oh, Julia L.; Whitman, Gary J.
Purpose: To investigate the incidence and local control of internal mammary lymph node metastases (IMN+) in patients with clinical N2 or N3 locally advanced breast cancer. Methods and Materials: We retrospectively reviewed the records of 809 breast cancer patients diagnosed with advanced nodal disease (clinical N2-3) who received radiation treatment at our institution from January 2000 December 2006. Patients were considered IMN+ on the basis of imaging studies. Results: We identified 112 of 809 patients who presented with IMN+ disease (13.8%) detected on ultrasound, computed tomography (CT), positron emission tomography/CT (PET/CT), and/or magnetic resonance imaging (MRI) studies. All 112 patients with IMN+ disease received anthracycline and taxane-based chemotherapy. Neoadjuvant chemotherapy (NCT) resulted in a complete response (CR) on imaging studies of IMN disease in 72.1% of patients. Excluding 16 patients with progressive disease, 96 patients received adjuvant radiation to the breast or the chest wall and the regional lymphatics including the IMN chain with a median dose of 60 Gy if the internal mammary lymph nodes normalized after chemotherapy and 66 Gy if they did not. The median follow-up of surviving patients was 41 months (8-118 months). For the 96 patients able to complete curative therapy, the actuarial 5-year IMN control rate, locoregional control, overall survival, and disease-free survival were 89%, 80%, 76%, and 56%. Conclusion: Over ten percent of patients with advanced nodal disease will have IMN metastases on imaging studies. Multimodality therapy including IMN irradiation achieves excellent rates of control in the IMN region and a DFS of more than 50% after curative treatment.
Clinical and Therapeutic Profiles of Heart Failure Patients admitted to a Tertiary Hospital, Aseer Region, Saudi Arabia
Assiri, Abdullah S
Objectives: This study aimed to investigate the clinical and therapeutic profiles of heart failure (HF) cases admitted to Aseer Central Hospital (ACH), Saudi Arabia. Methods: A retrospective cohort of 300 consecutive patients admitted with the diagnosis of HF to ACH from 1 June 2007 to 31 May 2009 were included in the study. Data on demographic variables, aetiologic factors, risk factors, and therapeutic profiles of patients with HF were collected and analysed. Results: The patients' mean age was 67.4 ± 13.7 years and 68.7% of them were male. The commonest aetiologies for HF were ischaemic heart disease (IHD) and hypertension in 38.3% and 33.3% of patients, respectively. A total of 61.3% of patients were diabetics. Other risk factors for HF included renal failure in 9.7%, atrial fibrillation in 13%, and anaemia in 48.3% of patients. Echocardiography was performed in 98.7% of cases: the average ejection fraction (EF) was 33% ± 17. Angiotensin converting enzyme inhibitors (ACEI) or angiotensin 2 receptor blockers were used in 68.3% of cases, β-blockers in 51.6% of cases and digoxin in 28.3% of cases. Conclusion: The major causes of HF in our study were IHD and hypertension. Diabetes and anaemia were common risk factors. The cohort constituted an intermediate HF risk group (ejection fraction (EF) 33%). Important therapeutic agents like angiotensin converting enzyme inhibitor I, β-blockers and digoxin were underutilised. Fostering such therapy in practice will lead to a better outcome in the management of HF patients. Anaemia was a significant risk factor in our HF patients and should be managed properly. PMID:21969895
Pseudospin Vortex Ring with a Nodal Line in Three Dimensions
NASA Astrophysics Data System (ADS)
Lim, Lih-King; Moessner, Roderich
We present a model of a topological semimetal in three dimensions whose energy spectrum exhibits a nodal line acting as a vortex ring; this in turn is linked by a pseudospin structure akin to that of a smoke ring. Contrary to a Weyl point node spectrum, the vortex ring gives rise to Skyrmionic pseudospin patterns in cuts on both sides of the nodal ring plane; this pattern covers the full Brillouin zone, thus leading to a fully extended chiral Fermi arc and a new, "maximal," anomalous Hall effect in a 3D semimetal. Tuning a model parameter shrinks the vortex ring until it vanishes, giving way to a pair of Weyl nodes of opposite chirality. This establishes a connection between two distinct momentum-space topologies—that of a vortex ring (a circle of singularity) and a monopole-antimonopole pair (two point singularities). We present the model both as a low-energy continuum and a two-band tight-binding lattice model. Its simplicity permits an analytical computation of its Landau level spectrum.
Amyloid precursor protein at node of Ranvier modulates nodal formation
Xu, De-En; Zhang, Wen-Min; Yang, Zara Zhuyun; Zhu, Hong-Mei; Yan, Ke; Li, Shao; Bagnard, Dominique; Dawe, Gavin S; Ma, Quan-Hong; Xiao, Zhi-Cheng
Amyloid precursor protein (APP), commonly associated with Alzheimer disease, is upregulated and distributes evenly along the injured axons, and therefore, also known as a marker of demyelinating axonal injury and axonal degeneration. However, the physiological distribution and function of APP along myelinated axons was unknown. We report that APP aggregates at nodes of Ranvier (NOR) in the myelinated central nervous system (CNS) axons but not in the peripheral nervous system (PNS). At CNS NORs, APP expression co-localizes with tenascin-R and is flanked by juxtaparanodal potassium channel expression demonstrating that APP localized to NOR. In APP-knockout (KO) mice, nodal length is significantly increased, while sodium channels are still clustered at NORs. Moreover, APP KO and APP-overexpressing transgenic (APP TG) mice exhibited a decreased and an increased thickness of myelin in spinal cords, respectively, although the changes are limited in comparison to their littermate WT mice. The thickness of myelin in APP KO sciatic nerve also increased in comparison to that in WT mice. Our observations indicate that APP acts as a novel component at CNS NORs, modulating nodal formation and has minor effects in promoting myelination. PMID:25482638
Symmetry Breaking in a Model for Nodal Cilia
NASA Astrophysics Data System (ADS)
Brokaw, Charles J.
Nodal cilia are very short cilia found in the embryonic node on the ventral surface of early mammalian embryos. They create a right to left fluid flow that is responsible for determining the normal asymmetry of the internal organs of the mammalian body. To do this, the distal end of the cilium must circle in a counterclockwise sense. Computer simulations with 3-dimensional models of flagella allow examination of 3-dimensional movements such as those of nodal cilia. 3-dimensional circling motions of short cilia can be achieved with velocity controlled models, in which dynein activity is regulated by sliding velocity. If dyneins on one outer doublet are controlled by the sliding velocity experienced by that doublet, the system is symmetric, and the 3-dimensional models can show either clockwise or counterclockwise circling. My computer simulations have examined two possible symmetry breaking mechanisms: 1) dyneins on doublet N are regulated by a mixture of the sliding velocities experienced by doublets N and N+1 (numbered in a clockwise direction, looking from the base). or 2) symmetry is broken by an off-axis force that produces a right-handed twist of the axoneme, consistent with observations that some dyneins can rotate their substrate microtubules in a clockwise direction.
Prevalence of heart failure with preserved ejection fraction in Latin American, Middle Eastern, and North African Regions in the I PREFER study (Identification of Patients With Heart Failure and PREserved Systolic Function: an epidemiological regional study).
Magaña-Serrano, José A; Almahmeed, Wael; Gomez, Efrain; Al-Shamiri, Mostafa; Adgar, Djamila; Sosner, Philippe; Herpin, Daniel
The aims of the present study were to estimate the prevalence of heart failure (HF) with preserved ejection fraction (HF-PEF) in patients with HF and to compare their clinical characteristics with those with reduced ejection fraction in non-Western countries. The left ventricular ejection fraction ≥ 45% if measured < 1 year before the visit was used to qualify the patients as having HF-PEF. Of the 2,536 consecutive outpatients with HF, 1990 (79%) had the EF values recorded. Of these patients, 1291 had HF-PEF, leading to an overall prevalence of 65% (95% confidence interval 63% to 67%). Compared to the patients with HF and a reduced ejection fraction, those with HF-PEF were more likely to be older (65 vs 62 years, p < 0.001), female (50% vs 28%, p < 0.001), and obese (39% vs 27%, p < 0.001). They more frequently had a history of hypertension (78% vs 53%, p < 0.001) and atrial fibrillation (29% vs 24%, p = 0.03) and less frequently had a history of myocardial infarction (21% vs 44%, p < 0.001). Only 29% of patients with HF-PEF and hypertension had optimal blood pressure control. Left ventricular hypertrophy was less frequent in those with HF-PEF (58% vs 69%, p < 0.001). The prevalence of HF-PEF was lower in the Middle East (41%), where coronary artery disease was more often found than in Latin America (69%) and North Africa (75%), where the rate of hypertension was greater. In conclusion, in the present diverse non-Western study, HF-PEF represented almost 2/3 of all HF cases in outpatients. HF-PEF mostly affects older patients, women, and the obese. Hypertension was the most frequently associated risk factor, highlighting the need for optimal blood pressure control.
Intensity-Modulated Radiotherapy for Oral Cavity Squamous Cell Carcinoma: Patterns of Failure and Predictors of Local Control
Daly, Megan E.; Le, Quynh-Thu; Kozak, Margaret M.; Maxim, Peter G.; Murphy, James D.; Hsu, Annie; Loo, Billy W.; Kaplan, Michael J.; Fischbein, Nancy J.; Chang, Daniel T.
Purpose: Few studies have evaluated the use of intensity-modulated radiotherapy (IMRT) for squamous cell carcinoma (SCC) of the oral cavity (OC). We report clinical outcomes and failure patterns for these patients. Methods and Materials: Between October 2002 and June 2009, 37 patients with newly diagnosed SCC of the OC underwent postoperative (30) or definitive (7) IMRT. Twenty-five patients (66%) received systemic therapy. The median follow-up was 38 months (range, 10-87 months). The median interval from surgery to RT was 5.9 weeks (range, 2.1-10.7 weeks). Results: Thirteen patients experienced local-regional failure at a median of 8.1 months (range, 2.4-31.9 months), and 2 additional patients experienced local recurrence between surgery and RT. Seven local failures occurred in-field (one with simultaneous nodal and distant disease) and two at the margin. Four regional failures occurred, two in-field and two out-of-field, one with synchronous metastases. Six patients experienced distant failure. The 3-year actuarial estimates of local control, local-regional control, freedom from distant metastasis, and overall survival were 67%, 53%, 81%, and 60% among postoperative patients, respectively, and 60%, 60%, 71%, and 57% among definitive patients. Four patients developed Grade {>=}2 chronic toxicity. Increased surgery to RT interval predicted for decreased LRC (p = 0.04). Conclusions: Local-regional control for SCC of the OC treated with IMRT with or without surgery remains unsatisfactory. Definitive and postoperative IMRT have favorable toxicity profiles. A surgery-to-RT interval of <6 weeks improves local-regional control. The predominant failure pattern was local, suggesting that both improvements in target delineation and radiosensitization and/or dose escalation are needed.
Prevention of AV Nodal Reentry Tachycardia by Oral Amiodarone: An Alternative Mechanism of Action
Gold, Robert L.; Haffajee, Charles I.; Entes, Kenneth L.
A 73-year-old man was noted to have atrioventricular (AV) nodal reentry tachycardia, which was induced during programmed electrical stimulation. After 1 month of oral amiodarone therapy, AV nodal reentry tachycardia was prevented by the prolongation of atrial refractoriness and not by direct action on the AV node itself. (Texas Heart Institute Journal 1987; 14:99-101) PMID:15227337
47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.
Code of Federal Regulations, 2014 CFR
... AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.503 Digital Electronic Message Service Nodal Stations. 10.6 GHz DEMS Nodal Stations may be... 47 Telecommunication 5 2014-10-01 2014-10-01 false Digital Electronic Message Service...
47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.
Code of Federal Regulations, 2012 CFR
... AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.503 Digital Electronic Message Service Nodal Stations. 10.6 GHz DEMS Nodal Stations may be... 47 Telecommunication 5 2012-10-01 2012-10-01 false Digital Electronic Message Service...
47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.
Code of Federal Regulations, 2013 CFR
... AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.503 Digital Electronic Message Service Nodal Stations. 10.6 GHz DEMS Nodal Stations may be... 47 Telecommunication 5 2013-10-01 2013-10-01 false Digital Electronic Message Service...
47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.
Code of Federal Regulations, 2011 CFR
... AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.503 Digital Electronic Message Service Nodal Stations. 10.6 GHz DEMS Nodal Stations may be... 47 Telecommunication 5 2011-10-01 2011-10-01 false Digital Electronic Message Service...
Asynchronous collision integrators: Explicit treatment of unilateral contact with friction and nodal restraints
Wolff, Sebastian; Bucher, Christian
This article presents asynchronous collision integrators and a simple asynchronous method treating nodal restraints. Asynchronous discretizations allow individual time step sizes for each spatial region, improving the efficiency of explicit time stepping for finite element meshes with heterogeneous element sizes. The article first introduces asynchronous variational integration being expressed by drift and kick operators. Linear nodal restraint conditions are solved by a simple projection of the forces that is shown to be equivalent to RATTLE. Unilateral contact is solved by an asynchronous variant of decomposition contact response. Therein, velocities are modified avoiding penetrations. Although decomposition contact response is solving a large system of linear equations (being critical for the numerical efficiency of explicit time stepping schemes) and is needing special treatment regarding overconstraint and linear dependency of the contact constraints (for example from double-sided node-to-surface contact or self-contact), the asynchronous strategy handles these situations efficiently and robust. Only a single constraint involving a very small number of degrees of freedom is considered at once leading to a very efficient solution. The treatment of friction is exemplified for the Coulomb model. Special care needs the contact of nodes that are subject to restraints. Together with the aforementioned projection for restraints, a novel efficient solution scheme can be presented. The collision integrator does not influence the critical time step. Hence, the time step can be chosen independently from the underlying time-stepping scheme. The time step may be fixed or time-adaptive. New demands on global collision detection are discussed exemplified by position codes and node-to-segment integration. Numerical examples illustrate convergence and efficiency of the new contact algorithm. Copyright © 2013 The Authors. International Journal for Numerical Methods in
Prognostic value of whole-body SUVmax of nodal and extra-nodal lesions detected by 18F-FDG PET/CT in extra-nodal NK/T-cell lymphoma
Gale, Robert Peter; Wang, Li; Xu, Ji; Qu, Xiao-Yan; Fan, Lei; Li, Tian-Lv; Li, Jian-Yong; Xu, Wei
We analyzed data from 54 newly-diagnosed persons with extra-nodal natural killer/T-cell (NK/T) lymphoma, who had a pretreatment 18F-FDG PET/CT study, to determine whether the sum of SUVmax of all the nodal and extra-nodal lesions predicted progression-free survival (PFS) and/or overall survival (OS). Three models (WB1SUVmax, WB2SUVmax, WB3SUVmax) based on the basis of the sum of SUVmax of the whole-body SUVmax of 11 nodal and 10 extra-nodal lesions were tested. The discrimination value of these models was evaluated using time-dependent receiver-operator characteristic (ROC) curves and corresponding areas under the curve (AUC) in training and validation cohorts. Findings were validated in an independent cohort of 15 subjects. ROC curve analysis showed the optimal cut-off values for WB1SUVmax, WB2SUVmax and WB3SUVmax were 15.8 (sensitivity 92%, specificity 67%, AUC 0.811; P<0.001), 12.7 (sensitivity 96%; specificity 57%; AUC 0.785; P<0.001) and 15.8 (sensitivity 88%; specificity 70%; AUC 0.793; P<0.001). Multivariate analyses indicated WB3SUVmax was independently associated with PFS (hazard ratio [HR]=3.67, 95% confidence interval [95% CI]=1.19, 11.29; P=0.023) and OS (HR= 4.51 [1.02, 19.91]; P=0.047). WB3SUVmax calculated based of the sum of the SUVmax of 3 nodal and 10 extra-nodal lesions was significantly associated with PFS and OS. PMID:27974685
Regional Lymph Node Uptake of [18F]Fluorodeoxyglucose After Definitive Chemoradiation Therapy Predicts Local-Regional Failure of Locally Advanced Non-Small Cell Lung Cancer: Results of ACRIN 6668/RTOG 0235
Markovina, Stephanie; Duan, Fenghai; Snyder, Bradley S.; Siegel, Barry A.; Machtay, Mitchell; Bradley, Jeffrey
Purpose/Objective(s) ACRIN 6668/RTOG 0235 demonstrated that standardized uptake value (SUV) on post-treatment [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) correlates with survival in locally advanced non-small cell lung cancer (NSCLC). This secondary analysis determines if SUV of regional lymph nodes (RLNs) on post-treatment FDG-PET correlates with patient outcomes. Methods and Materials Included for analysis were patients treated with concurrent chemoradiation therapy using radiation doses ≥60 Gy, with identifiable FDG-avid RLNs (distinct from primary tumor) on pre-treatment FDG-PET, and post-treatment FDG-PET data. ACRIN Core Laboratory SUV measurements were used. Event time was calculated from the date of post-treatment FDG-PET. Local-regional failure was defined as failure within the treated RT volume and reported by the treating institution. Statistical analyses included Wilcoxon signed-rank test, Kaplan-Meier curves (log rank test), and Cox proportional hazards regression modeling. Results Of 234 trial-eligible patients, 139 (59%) had uptake in both primary tumor and RLNs on pre-treatment FDG-PET, and had SUV data from post-treatment FDG-PET. Maximum SUV was greater for primary tumor than for RLNs before treatment (p<0.001), but not different post-treatment (p=0.320). Post-treatment SUV of RLNs was not associated with overall survival. However, elevated post-treatment SUV of RLNs, both the absolute value and the percent residual activity compared to the pre-treatment SUV, were associated with inferior local-regional control (p<0.001). Conclusions High residual metabolic activity in RLNs on post-treatment FDG-PET is associated with worse local-regional control. Based on these data, future trials evaluating a radiotherapy boost should consider inclusion of both primary tumor and FDG-avid RLNs in the boost volume to maximize local-regional control. PMID:26461002
Augmented weighted diamond form of the linear nodal scheme for Cartesian coordinate systems
Walters, W.F.
The equations of the high order linear nodal numerical scheme are cast in an augmented weighted difference form for three-dimensional Cartesian nodes. The coupling exhibited by these equations indicate that this new algorithm is simpler and hence faster than previous nodal schemes of this degree of accuracy. A well-logging problem and a fast reactor problem are examined. The new scheme developed here is compared with the classical linear-linear nodal scheme and the diamond difference scheme. For the well-logging problem, it is found that the new scheme is both faster and simpler than the classical linear-linear nodal scheme while sacrificing little in accuracy. Even though the new scheme is more accurate than the diamond difference scheme for the reactor problem, the results indicate that state of the art acceleration methods are needed for nodal schemes.
Magnetic susceptibility in three-dimensional nodal semimetals
NASA Astrophysics Data System (ADS)
Koshino, Mikito; Hizbullah, Intan Fatimah
We study the magnetic susceptibility in various three-dimensional gapless systems, including Dirac and Weyl semimetals, and a line-node semimetal. The susceptibility is decomposed into the orbital term, the spin term and also the spin-orbit cross term, which is caused by the spin-orbit interaction. We show that the orbital susceptibility logarithmically diverges at the band touching energy in the point-node case, while it exhibits a stronger δ -function singularity in the line node case. The spin-orbit cross term is shown to be paramagnetic in the electron side while diamagnetic in the hole side, in contrast with other two terms which are both even functions in Fermi energy. The spin-orbit cross term in the nodal semimetal is found to be directly related to the chiral surface current induced by the topological surface modes.
Magnetic response in three-dimensional nodal semimetals
NASA Astrophysics Data System (ADS)
Koshino, Mikito; Hizbullah, Intan Fatimah
We study the magnetic response in various three-dimensional gapless systems, including Dirac and Weyl semimetals and a line-node semimetal. We show that the susceptibility is decomposed into the orbital term, the spin term and also the spin-orbit cross term which is caused by the spin-orbit interaction. We show that the orbital susceptibility logarithmically diverges at the band touching energy in the point-node case, while it exhibits a stronger delta-function singularity in the line node case. The spin-orbit cross term is shown to be paramagnetic in the electron side while diamagnetic in the hole side, in contrast with other two terms which are both even functions in Fermi energy. The spin-orbit cross term in the nodal semimetal is found to be directly related to the chiral surface current induced by the topological surface modes.
Improving the Accuracy of High-Order Nodal Transport Methods
Azmy, Y.Y.; Buscaglia, G.C.; Zamonsky, O.M.
This paper outlines some recent advances towards improving the accuracy of neutron transport calculations using the Arbitrarily High Order Transport-Nodal (AHOT-N) Method. These advances consist of several contributions: (a) A formula for the spatial weights that allows for the polynomial order to be raised arbitrarily high without suffering adverse effects from round-off error; (b) A reconstruction technique for the angular flux, based upon a recursive formula, that reduces the pointwise error by one ordeq (c) An a posterior error indicator that estimates the true error and its distribution throughout the domain, so that it can be used for adaptively refining the approximation. Present results are mainly for ID, extension to 2D-3D is in progress.
Improving the Accuracy of High-Order Nodal Transport Methods
Azmy, Y.Y.; Buscaglia, G.C.; Zamonsky, O.M.
This paper outlines some recent advances towards improving the accuracy of neutron calculations using the Arbitrarily High Order Transport-Nodal (AHOT-N) Method. These transport advances consist of several contributions: (a) A formula for the spatial weights that allows for the polynomial order to be raised arbitrarily high without suffering from pollution from round-off, error; (b) A reconstruction technique for the angular flux, based upon a recursive formula, that reduces the pointwise error by one order; (c) An a posterior error indicator that estimates the true error and its distribution throughout the domain, so that it can be used for adaptively reftig the approximation. Present results are mainly for ID, extension to 2D-3D is in progress.
Contemporary Management of Recurrent Nodal Disease in Differentiated Thyroid Carcinoma
Na'ara, Shorook; Amit, Moran; Fridman, Eran; Gil, Ziv
Differentiated thyroid carcinoma (DTC) comprises over 90% of thyroid tumors and includes papillary and follicular carcinomas. Patients with DTC have an excellent prognosis, with a 10-year survival rate of over 90%. However, the risk of recurrent tumor ranges between 5% and 30% within 10 years of the initial diagnosis. Cervical lymph node disease accounts for the majority of recurrences and in most cases is detected during follow-up by ultrasound or elevated levels of serum thyroglobulin. Recurrent disease is accompanied by increased morbidity. The mainstay of treatment of nodal recurrence is surgical management. We provide an overview of the literature addressing surgical management of recurrent or persistent lymph node disease in patients with DTC. PMID:26886954
Static benchmarking of the NESTLE advanced nodal code
Mosteller, R.D.
Results from the NESTLE advanced nodal code are presented for multidimensional numerical benchmarks representing four different types of reactors, and predictions from NESTLE are compared with measured data from pressurized water reactors (PWRs). The numerical benchmarks include cases representative of PWRs, boiling water reactors (BWRs), CANDU heavy water reactors (HWRs), and high-temperature gas-cooled reactors (HTGRs). The measured PWR data include critical soluble boron concentrations and isothermal temperature coefficients of reactivity. The results demonstrate that NESTLE correctly solves the multigroup diffusion equations for both Cartesian and hexagonal geometries, that it reliably calculates k{sub eff} and reactivity coefficients for PWRs, and that--subsequent to the incorporation of additional thermal-hydraulic models--it will be able to perform accurate calculations for the corresponding parameters in BWRs, HWRs, and HTGRs as well.
On-line application of the PANTHER advanced nodal code
Hutt, P.K.; Knight, M.P. )
Over the last few years, Nuclear Electric has developed an integrated core performance code package for both light water reactors (LWRs) and advanced gas-cooled reactors (AGRs) that can perform a comprehensive range of calculations for fuel cycle design, safety analysis, and on-line operational support for such plants. The package consists of the following codes: WIMS for lattice physics, PANTHER whole reactor nodal flux and AGR thermal hydraulics, VIPRE for LWR thermal hydraulics, and ENIGMA for fuel performance. These codes are integrated within a UNIX-based interactive system called the Reactor Physics Workbench (RPW), which provides an interactive graphic user interface and quality assurance records/data management. The RPW can also control calculational sequences and data flows. The package has been designed to run both off-line and on-line accessing plant data through the RPW.
Does the Jet Stream Indicate the Presence of Transient EMFs also Detected by Native American Environmental Scientists? These Variable EMFs May Impact Regional Power Failures.
NASA Astrophysics Data System (ADS)
Pawa Matagamon, Sagamo; Balam Matagmaon, Chan
Ohios Serpent Mound, and other instruments like a schist-like-slate serpent effigy may be monitors that detect transient and periodic electromagnetic field (EMF) effects. Physics courses show that ionic beams transversely entering magnetic fields are deflected at constant velocity into circular paths. Our abstracts of earlier APS/AAPT meetings used this analysis as the basis for tornado and hurricane modeling. Ionized jet streams will be deflected if they penetrate a new, transient region of magnetic fields. Clockwise horizontal deflection of a positively ionized jet stream requires this time-varying magnetic field to be directed perpendicularly away from the earth. One model is that a north magnetic field from a secondary magnetic dipole acts within an anthropomorphized Mother Earth, (M E). Power grid failures are influenced by M Es predictable voltages superposed onto grid frequencies via Faradays Law! Mayan youth and rulers seem to have detected the equivalent.
ProNodal acts via FGFR3 to govern duration of Shh expression in the prechordal mesoderm
Ellis, Pamela S.; Burbridge, Sarah; Soubes, Sandrine; Ohyama, Kyoji; Ben-Haim, Nadav; Chen, Canhe; Dale, Kim; Shen, Michael M.; Constam, Daniel; Placzek, Marysia
The secreted glycoprotein sonic hedgehog (Shh) is expressed in the prechordal mesoderm, where it plays a crucial role in induction and patterning of the ventral forebrain. Currently little is known about how Shh is regulated in prechordal tissue. Here we show that in the embryonic chick, Shh is expressed transiently in prechordal mesoderm, and is governed by unprocessed Nodal. Exposure of prechordal mesoderm microcultures to Nodal-conditioned medium, the Nodal inhibitor CerS, or to an ALK4/5/7 inhibitor reveals that Nodal is required to maintain both Shh and Gsc expression, but whereas Gsc is largely maintained through canonical signalling, Nodal signals through a non-canonical route to maintain Shh. Further, Shh expression can be maintained by a recombinant Nodal cleavage mutant, proNodal, but not by purified mature Nodal. A number of lines of evidence suggest that proNodal acts via FGFR3. ProNodal and FGFR3 co-immunoprecipitate and proNodal increases FGFR3 tyrosine phosphorylation. In microcultures, soluble FGFR3 abolishes Shh without affecting Gsc expression. Further, prechordal mesoderm cells in which Fgfr3 expression is reduced by Fgfr3 siRNA fail to bind to proNodal. Finally, targeted electroporation of Fgfr3 siRNA to prechordal mesoderm in vivo results in premature Shh downregulation without affecting Gsc. We report an inverse correlation between proNodal-FGFR3 signalling and pSmad1/5/8, and show that proNodal-FGFR3 signalling antagonises BMP-mediated pSmad1/5/8 signalling, which is poised to downregulate Shh. Our studies suggest that proNodal/FGFR3 signalling governs Shh duration by repressing canonical BMP signalling, and that local BMPs rapidly silence Shh once endogenous Nodal-FGFR3 signalling is downregulated. PMID:26417042
Nodal promotes mir206 expression to control convergence and extension movements during zebrafish gastrulation.
Liu, Xiuli; Ma, Yuanqing; Zhang, Congwei; Wei, Shi; Cao, Yu; Wang, Qiang
Nodal, a member of the transforming growth factor β (TGF-β) superfamily, has been shown to play a role in mesendoderm induction and gastrulation movements. The activity of Nodal signaling can be modulated by microRNAs (miRNAs) as previously reported, but little is known about which miRNAs are regulated by Nodal during gastrulation. In the present study, we found that the expression of mir206, one of the most abundant miRNAs during zebrafish early embryo development, is regulated by Nodal signaling. Abrogation of Nodal signal activity results in defective convergence and extension (CE) movements, and these cell migration defects can be rescued by supplying an excess of mir206, suggesting that mir206 acts downstream of Nodal signaling to regulate CE movements. Furthermore, in mir206 morphants, the expression of cell adhesion molecule E-cadherin is significantly increased, while the key transcriptional repressor of E-cadherin, snail1a, is depressed. Our study uncovers a novel mechanism by which Nodal-regulated mir206 modulates gastrulation movements in connection with the Snail/E-cadherin pathway.
The embryonic morphogen, Nodal, is associated with channel-like structures in human malignant melanoma xenografts.
McAllister, Josephine C; Zhan, Qian; Weishaupt, Carsten; Hsu, Mei-Yu; Murphy, George F
Formation of channel-like structures, also termed vasculogenic mimicry (VM), describes the ability of aggressive melanoma cells to form PAS-positive anastomosing structures that correlate with tumor virulence. This phenomenon may indicate differentiation plasticity, a feature melanoma cells may share with stem cells in the developing embryo. Recent studies have indicated that VM and tumorigenicity of human malignant melanoma may depend on the signaling pathways of an embryonic morphogen, Nodal. However, given the secretory nature of Nodal protein and melanoma cell heterogeneity, it remains unclear whether the Nodal-expressing cells participate directly or indirectly in VM that is potentially related to tumorigenic growth. We have developed a humanized murine xenograft model in which developing human melanomas may be sequentially studied during early stages of tumorigenic growth within a physiological human dermal microenvironment. Nodal protein localized diffusely to melanoma cell membranes, with occasional foci of accentuated reactivity in patterns suggestive of channel formation. Similar findings were detected in a limited number of patient-derived tumors. In situ hybridization confirmed Nodal mRNA to be restricted to tumor cells within xenografts that formed arborizing networks in patterns consistent with VM. These data indicate that Nodal gene expression is associated with formation of VM-like structures in a physiologically relevant model of human melanoma tumorigenesis, and further support a key role for Nodal expression in the formation of channel-like structures. The humanized xenograft model should be useful in future studies to define the mechanistic pathways responsible for VM and melanoma progression.
Nicalin and its binding partner Nomo are novel Nodal signaling antagonists.
Haffner, Christof; Frauli, Mélanie; Topp, Stephanie; Irmler, Martin; Hofmann, Kay; Regula, Jörg T; Bally-Cuif, Laure; Haass, Christian
Nodals are signaling factors of the transforming growth factor-beta (TGFbeta) superfamily with a key role in vertebrate development. They control a variety of cell fate decisions required for the establishment of the embryonic body plan. We have identified two highly conserved transmembrane proteins, Nicalin and Nomo (Nodal modulator, previously known as pM5), as novel antagonists of Nodal signaling. Nicalin is distantly related to Nicastrin, a component of the Alzheimer's disease-associated gamma-secretase, and forms a complex with Nomo. Ectopic expression of both proteins in zebrafish embryos causes cyclopia, a phenotype that can arise from a defect in mesendoderm patterning mediated by the Nodal signaling pathway. Accordingly, downregulation of Nomo resulted in an increase in anterior axial mesendoderm and the development of an enlarged hatching gland. Inhibition of Nodal signaling by ectopic expression of Lefty was rescued by reducing Nomo levels. Furthermore, Nodal- as well as Activin-induced signaling was inhibited by Nicalin and Nomo in a cell-based reporter assay. Our data demonstrate that the Nicalin/Nomo complex antagonizes Nodal signaling during mesendodermal patterning in zebrafish.
Nicalin and its binding partner Nomo are novel Nodal signaling antagonists
Haffner, Christof; Frauli, Mélanie; Topp, Stephanie; Irmler, Martin; Hofmann, Kay; Regula, Jörg T; Bally-Cuif, Laure; Haass, Christian
Nodals are signaling factors of the transforming growth factor-β (TGFβ) superfamily with a key role in vertebrate development. They control a variety of cell fate decisions required for the establishment of the embryonic body plan. We have identified two highly conserved transmembrane proteins, Nicalin and Nomo (Nodal modulator, previously known as pM5), as novel antagonists of Nodal signaling. Nicalin is distantly related to Nicastrin, a component of the Alzheimer's disease-associated γ-secretase, and forms a complex with Nomo. Ectopic expression of both proteins in zebrafish embryos causes cyclopia, a phenotype that can arise from a defect in mesendoderm patterning mediated by the Nodal signaling pathway. Accordingly, downregulation of Nomo resulted in an increase in anterior axial mesendoderm and the development of an enlarged hatching gland. Inhibition of Nodal signaling by ectopic expression of Lefty was rescued by reducing Nomo levels. Furthermore, Nodal- as well as Activin-induced signaling was inhibited by Nicalin and Nomo in a cell-based reporter assay. Our data demonstrate that the Nicalin/Nomo complex antagonizes Nodal signaling during mesendodermal patterning in zebrafish. PMID:15257293
Congestive Heart Failure Leads to Prolongation of the PR Interval and Atrioventricular Junction Enlargement and Ion Channel Remodelling in the Rabbit.
Nikolaidou, Theodora; Cai, Xue J; Stephenson, Robert S; Yanni, Joseph; Lowe, Tristan; Atkinson, Andrew J; Jones, Caroline B; Sardar, Rida; Corno, Antonio F; Dobrzynski, Halina; Withers, Philip J; Jarvis, Jonathan C; Hart, George; Boyett, Mark R
Heart failure is a major killer worldwide. Atrioventricular conduction block is common in heart failure; it is associated with worse outcomes and can lead to syncope and bradycardic death. We examine the effect of heart failure on anatomical and ion channel remodelling in the rabbit atrioventricular junction (AVJ). Heart failure was induced in New Zealand rabbits by disruption of the aortic valve and banding of the abdominal aorta resulting in volume and pressure overload. Laser micro-dissection and real-time polymerase chain reaction (RT-PCR) were employed to investigate the effects of heart failure on ion channel remodelling in four regions of the rabbit AVJ and in septal tissues. Investigation of the AVJ anatomy was performed using micro-computed tomography (micro-CT). Heart failure animals developed first degree heart block. Heart failure caused ventricular myocardial volume increase with a 35% elongation of the AVJ. There was downregulation of HCN1 and Cx43 mRNA transcripts across all regions and downregulation of Cav1.3 in the transitional tissue. Cx40 mRNA was significantly downregulated in the atrial septum and AVJ tissues but not in the ventricular septum. mRNA abundance for ANP, CLCN2 and Navβ1 was increased with heart failure; Nav1.1 was increased in the inferior nodal extension/compact node area. Heart failure in the rabbit leads to prolongation of the PR interval and this is accompanied by downregulation of HCN1, Cav1.3, Cx40 and Cx43 mRNAs and anatomical enlargement of the entire heart and AVJ.
Congestive Heart Failure Leads to Prolongation of the PR Interval and Atrioventricular Junction Enlargement and Ion Channel Remodelling in the Rabbit
Nikolaidou, Theodora; Cai, Xue J.; Stephenson, Robert S.; Yanni, Joseph; Lowe, Tristan; Atkinson, Andrew J.; Jones, Caroline B.; Sardar, Rida; Corno, Antonio F.; Dobrzynski, Halina; Withers, Philip J.; Jarvis, Jonathan C.; Hart, George; Boyett, Mark R.
Heart failure is a major killer worldwide. Atrioventricular conduction block is common in heart failure; it is associated with worse outcomes and can lead to syncope and bradycardic death. We examine the effect of heart failure on anatomical and ion channel remodelling in the rabbit atrioventricular junction (AVJ). Heart failure was induced in New Zealand rabbits by disruption of the aortic valve and banding of the abdominal aorta resulting in volume and pressure overload. Laser micro-dissection and real-time polymerase chain reaction (RT-PCR) were employed to investigate the effects of heart failure on ion channel remodelling in four regions of the rabbit AVJ and in septal tissues. Investigation of the AVJ anatomy was performed using micro-computed tomography (micro-CT). Heart failure animals developed first degree heart block. Heart failure caused ventricular myocardial volume increase with a 35% elongation of the AVJ. There was downregulation of HCN1 and Cx43 mRNA transcripts across all regions and downregulation of Cav1.3 in the transitional tissue. Cx40 mRNA was significantly downregulated in the atrial septum and AVJ tissues but not in the ventricular septum. mRNA abundance for ANP, CLCN2 and Navβ1 was increased with heart failure; Nav1.1 was increased in the inferior nodal extension/compact node area. Heart failure in the rabbit leads to prolongation of the PR interval and this is accompanied by downregulation of HCN1, Cav1.3, Cx40 and Cx43 mRNAs and anatomical enlargement of the entire heart and AVJ. PMID:26509807
Respiratory failure happens when not enough oxygen passes from your lungs into your blood. Your body's organs, ... brain, need oxygen-rich blood to work well. Respiratory failure also can happen if your lungs can' ...
Identification and functional characterization of NODAL rare variants in heterotaxy and isolated cardiovascular malformations
Mohapatra, Bhagyalaxmi; Casey, Brett; Li, Hua; Ho-Dawson, Trang; Smith, Liana; Fernbach, Susan D.; Molinari, Laura; Niesh, Stephen R.; Jefferies, John Lynn; Craigen, William J.; Towbin, Jeffrey A.; Belmont, John W.; Ware, Stephanie M.
NODAL and its signaling pathway are known to play a key role in specification and patterning of vertebrate embryos. Mutations in several genes encoding components of the NODAL signaling pathway have previously been implicated in the pathogenesis of human left–right (LR) patterning defects. Therefore, NODAL, a member of TGF-β superfamily of developmental regulators, is a strong candidate to be functionally involved in congenital LR axis patterning defects or heterotaxy. Here we have investigated whether variants in NODAL are present in patients with heterotaxy and/or isolated cardiovascular malformations (CVM) thought to be caused by abnormal heart tube looping. Analysis of a large cohort of cases (n = 269) affected with either classic heterotaxy or looping CVM revealed four different missense variants, one in-frame insertion/deletion and two conserved splice site variants in 14 unrelated subjects (14/269, 5.2%). Although similar with regard to other associated defects, individuals with the NODAL mutations had a significantly higher occurrence of pulmonary valve atresia (P = 0.001) compared with cases without a detectable NODAL mutation. Functional analyses demonstrate that the missense variant forms of NODAL exhibit significant impairment of signaling as measured by decreased Cripto (TDGF-1) co-receptor-mediated activation of artificial reporters. Expression of these NODAL proteins also led to reduced induction of Smad2 phosphorylation and impaired Smad2 nuclear import. Taken together, these results support a role for mutations and rare deleterious variants in NODAL as a cause for sporadic human LR patterning defects. PMID:19064609
Cerberus-Nodal-Lefty-Pitx signaling cascade controls left-right asymmetry in amphioxus.
Li, Guang; Liu, Xian; Xing, Chaofan; Zhang, Huayang; Shimeld, Sebastian M; Wang, Yiquan
Many bilaterally symmetrical animals develop genetically programmed left-right asymmetries. In vertebrates, this process is under the control of Nodal signaling, which is restricted to the left side by Nodal antagonists Cerberus and Lefty. Amphioxus, the earliest diverging chordate lineage, has profound left-right asymmetry as a larva. We show that Cerberus, Nodal, Lefty, and their target transcription factor Pitx are sequentially activated in amphioxus embryos. We then address their function by transcription activator-like effector nucleases (TALEN)-based knockout and heat-shock promoter (HSP)-driven overexpression. Knockout of Cerberus leads to ectopic right-sided expression of Nodal, Lefty, and Pitx, whereas overexpression of Cerberus represses their left-sided expression. Overexpression of Nodal in turn represses Cerberus and activates Lefty and Pitx ectopically on the right side. We also show Lefty represses Nodal, whereas Pitx activates Nodal These data combine in a model in which Cerberus determines whether the left-sided gene expression cassette is activated or repressed. These regulatory steps are essential for normal left-right asymmetry to develop, as when they are disrupted embryos may instead form two phenotypic left sides or two phenotypic right sides. Our study shows the regulatory cassette controlling left-right asymmetry was in place in the ancestor of amphioxus and vertebrates. This includes the Nodal inhibitors Cerberus and Lefty, both of which operate in feedback loops with Nodal and combine to establish asymmetric Pitx expression. Cerberus and Lefty are missing from most invertebrate lineages, marking this mechanism as an innovation in the lineage leading to modern chordates.
Conformational features and binding affinities to Cripto, ALK7 and ALK4 of Nodal synthetic fragments.
Calvanese, Luisa; Sandomenico, Annamaria; Caporale, Andrea; Focà, Annalia; Focà, Giuseppina; D'Auria, Gabriella; Falcigno, Lucia; Ruvo, Menotti
Nodal, a member of the TGF-β superfamily, is a potent embryonic morphogen also implicated in tumor progression. As for other TGF-βs, it triggers the signaling functions through the interaction with the extracellular domains of type I and type II serine/threonine kinase receptors and with the co-receptor Cripto. Recently, we reported the molecular models of Nodal in complex with its type I receptors (ALK4 and ALK7) as well as with Cripto, as obtained by homology modeling and docking simulations. From such models, potential binding epitopes have been identified. To validate such hypotheses, a series of mutated Nodal fragments have been synthesized. These peptide analogs encompass residues 44-67 of the Nodal protein, corresponding to the pre-helix loop and the H3 helix, and reproduce the wild-type sequence or bear some modifications to evaluate the hot-spot role of modified residues in the receptor binding. Here, we show the structural characterization in solution by CD and NMR of the Nodal peptides and the measurement of binding affinity toward Cripto by surface plasmon resonance. Data collected by both conformational analyses and binding measurements suggest a role for Y58 of Nodal in the recognition with Cripto and confirm that previously reported for E49 and E50. Surface plasmon resonance binding assays with recombinant proteins show that Nodal interacts in vitro also with ALK7 and ALK4 and preliminary data, generated using the Nodal synthetic fragments, suggest that Y58 of Nodal may also be involved in the recognition with these protein partners.
Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... Tiredness and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...
Detection of 18.6 year nodal induced drought in the Patagonian Andes
NASA Astrophysics Data System (ADS)
Currie, Robert G.
Analysis of tree-ring chronologies from the Patagonian Andes yields evidence for the 18.6 yr lunar nodal term in drought/flood. The mean discrepancy between epochs of drought/flood and the nodal tide since AD 1600 is 0.7 ± 2.2 yr, but the polarity of the signal is apparently bimodal. From nodal epoch 1750.0 through 1898.9 drought and tide were in phase, whereas prior to 1750.0 and subsequent to 1898.9 drought and tide were out of phase. There is evidence also for the solar cycle drought signal in the data.
Long-Term Efficacy and Patterns of Failure After Accelerated Partial Breast Irradiation: A Molecular Assay-Based Clonality Evaluation
Vicini, Frank A. . E-mail: email@example.com; Antonucci, J. Vito; Wallace, Michelle R.N.; Gilbert, Samuel; Goldstein, Neal S.; Kestin, Larry; Chen, Peter; Kunzman, Jonathan; Boike, Thomas; Benitez, Pamela; Martinez, Alvaro
Purpose: To determine the long-term efficacy and cosmetic results of accelerated partial breast irradiation (APBI) by reviewing our institution's experience. Methods and Materials: A total of 199 patients with early-stage breast cancer were treated prospectively with adjuvant APBI after lumpectomy using interstitial brachytherapy. All patients had negative margins, 82% had Stage I disease, median tumor size was 1.1 cm, and 12% had positive lymph nodes. The median follow-up for surviving patients was 8.6 years. Fifty-three patients (27%) have been followed for {>=}10 years. Results: Six ipsilateral breast tumor recurrences (IBTRs) were observed, for a 5-year and 10-year actuarial rate of 1.6% and 3.8%, respectively. A total of three regional nodal failures were observed, for a 10-year actuarial rate of 1.6%. Five contralateral breast cancers developed, for a 5- and 10-year actuarial rate of 2.2% and 5.2%, respectively. The type of IBTR (clonally related vs. clonally distinct) was analyzed using a polymerase chain reaction-based loss of heterozygosity assay. Eighty-three percent of IBTRs (n = 5) were classified as clonally related. Multiple clinical, pathologic, and treatment-related factors were analyzed for an association with the development of an IBTR, regional nodal failure, or contralateral breast cancer. On multivariate analysis, no variable was associated with any of these events. Cosmetic results were rated as excellent/good in 99% of patients. Conclusions: Long-term results with APBI using interstitial brachytherapy continue to demonstrate excellent long-term local and regional control rates and cosmetic results. According to a polymerase chain reaction-based loss of heterozygosity assay, 83% of recurrences were classified as clonally related.
Relation between finite element methods and nodal methods in transport theory
Walters, W.F.
This paper examines the relationship between nodal methods and finite-element methods for solving the discrete-ordinates form of the transport equation in x-y geometry. Specifically, we will examine the relation of three finite-element schemes to the linear-linear (LL) and linear-nodal (LN) nodal schemes. The three finite-element schemes are the linear-continuous-diamond-difference (DD) scheme, the linear-discontinuous (LD) scheme, and the quadratic-discontinuous (QD) scheme. A brief derivation of the (LL) and (LN) nodal schemes is given in the third section of this paper. The approximations that cause the LL scheme to reduce to the DD, LD, and QD schemes are then indicated. An extremely simple method of deriving the finite-element schemes is then introduced.
Nodal Domain Statistics for Quantum Maps, Percolation, and Stochastic Loewner Evolution
Keating, J. P.; Marklof, J.; Williams, I. G.
We develop a percolation model for nodal domains in the eigenvectors of quantum chaotic torus maps. Our model follows directly from the assumption that the quantum maps are described by random matrix theory. Its accuracy in predicting statistical properties of the nodal domains is demonstrated for perturbed cat maps and supports the use of percolation theory to describe the wave functions of general Hamiltonian systems. We also demonstrate that the nodal domains of the perturbed cat maps obey the Cardy crossing formula and find evidence that the boundaries of the nodal domains are described by stochastic Loewner evolution with diffusion constant {kappa} close to the expected value of 6, suggesting that quantum chaotic wave functions may exhibit conformal invariance in the semiclassical limit.
ANOVA-HDMR structure of the higher order nodal diffusion solution
Bokov, P. M.; Prinsloo, R. H.; Tomasevic, D. I.
Nodal diffusion methods still represent a standard in global reactor calculations, but employ some ad-hoc approximations (such as the quadratic leakage approximation) which limit their accuracy in cases where reference quality solutions are sought. In this work we solve the nodal diffusion equations utilizing the so-called higher-order nodal methods to generate reference quality solutions and to decompose the obtained solutions via a technique known as High Dimensional Model Representation (HDMR). This representation and associated decomposition of the solution provides a new formulation of the transverse leakage term. The HDMR structure is investigated via the technique of Analysis of Variance (ANOVA), which indicates why the existing class of transversely-integrated nodal methods prove to be so successful. Furthermore, the analysis leads to a potential solution method for generating reference quality solutions at a much reduced calculational cost, by applying the ANOVA technique to the full higher order solution. (authors)
Dose-dependent Nodal/Smad signals pattern the early mouse embryo.
Robertson, Elizabeth J
Nodal signals in the early post-implantation stage embryo are essential to establish initial proximal-distal (P-D) polarity and generate the final anterior-posterior (A-P) body axis. Nodal signaling in the epiblast results in the phosphorylation of Smad2 in the overlying visceral endoderm necessary to induce the AVE, in part via Smad2-dependent activation of the T-box gene Eomesodermin. Slightly later following mesoderm induction a continuum of dose-dependent Nodal signaling during the process of gastrulation underlies specification of mesodermal and definitive endoderm progenitors. Dynamic Nodal expression during the critical 72 h time window immediately following implantation, accomplished by a series of feed-back and feed-forward mechanisms serves to provide key positional cues required for establishment of the body plan and controls cell fate decisions in the early mammalian embryo.
Bidecadal variability in the Bering Sea and the relation with 18.6 year period nodal tidal cycle
NASA Astrophysics Data System (ADS)
Osafune, S.; Yasuda, I.
Bidecadal variations are investigated in the Bering Sea, especially in the southeastern basin adjacent to the Aleutian passes, where vertical mixing may be strong because of the diurnal tide. Those variations found in this region are synchronized with the 18.6 year period nodal tidal cycle, and the temporal patterns are similar to ones around the northwestern subarctic Pacific near the Kuril Straits reported by a previous study. Salinity and density in the upper layer are high in the periods when the diurnal tide is strong. In the intermediate layer, layer thickness is large, and isopycnal potential temperature and apparent oxygen utilization are low in the same periods. It is shown that these variations are consistent with the patterns expected from the nodal modulation of vertical mixing, and a simple two-dimensional model, assuming a balance between anomalous vertical mixing and advection of anomaly by the mean current, succeeds to some extent in explaining the variations of the upper layer salinity and isopycnal temperature and apparent oxygen utilization in the intermediate layer.
Final Report, NERI Project: ''An Innovative Reactor Analysis Methodology Based on a Quasidiffusion Nodal Core Model''
Dmitriy Y. Anistratov; Marvin L. Adams; Todd S. Palmer; Kord S. Smith; Kevin Clarno; Hikaru Hiruta; Razvan Nes
OAK (B204) Final Report, NERI Project: ''An Innovative Reactor Analysis Methodology Based on a Quasidiffusion Nodal Core Model'' The present generation of reactor analysis methods uses few-group nodal diffusion approximations to calculate full-core eigenvalues and power distributions. The cross sections, diffusion coefficients, and discontinuity factors (collectively called ''group constants'') in the nodal diffusion equations are parameterized as functions of many variables, ranging from the obvious (temperature, boron concentration, etc.) to the more obscure (spectral index, moderator temperature history, etc.). These group constants, and their variations as functions of the many variables, are calculated by assembly-level transport codes. The current methodology has two main weaknesses that this project addressed. The first weakness is the diffusion approximation in the full-core calculation; this can be significantly inaccurate at interfaces between different assemblies. This project used the nodal diffusion framework to implement nodal quasidiffusion equations, which can capture transport effects to an arbitrary degree of accuracy. The second weakness is in the parameterization of the group constants; current models do not always perform well, especially at interfaces between unlike assemblies. The project developed a theoretical foundation for parameterization and homogenization models and used that theory to devise improved models. The new models were extended to tabulate information that the nodal quasidiffusion equations can use to capture transport effects in full-core calculations.
Topological Dirac nodal lines and surface charges in fcc alkaline earth metals
Hirayama, Motoaki; Okugawa, Ryo; Miyake, Takashi; Murakami, Shuichi
In nodal-line semimetals, the gaps close along loops in k space, which are not at high-symmetry points. Typical mechanisms for the emergence of nodal lines involve mirror symmetry and the π Berry phase. Here we show via ab initio calculations that fcc calcium (Ca), strontium (Sr) and ytterbium (Yb) have topological nodal lines with the π Berry phase near the Fermi level, when spin–orbit interaction is neglected. In particular, Ca becomes a nodal-line semimetal at high pressure. Owing to nodal lines, the Zak phase becomes either π or 0, depending on the wavevector k, and the π Zak phase leads to surface polarization charge. Carriers eventually screen it, leaving behind large surface dipoles. In materials with nodal lines, both the large surface polarization charge and the emergent drumhead surface states enhance Rashba splitting when heavy adatoms are present, as we have shown to occur in Bi/Sr(111) and in Bi/Ag(111). PMID:28074835
The nodal inhibitor Coco is a critical target of leftward flow in Xenopus.
Schweickert, Axel; Vick, Philipp; Getwan, Maike; Weber, Thomas; Schneider, Isabelle; Eberhardt, Melanie; Beyer, Tina; Pachur, Anke; Blum, Martin
Vertebrate laterality, which is manifested by asymmetrically placed organs [1], depends on asymmetric activation of the Nodal signaling cascade in the left lateral plate mesoderm [2]. In fish, amphibians, and mammals, a cilia-driven leftward flow of extracellular fluid acts upstream of the Nodal cascade [3-6]. The direct target of flow has remained elusive. In Xenopus, flow occurs at the gastrocoel roof plate (GRP) in the dorsal midline of the embryo [4, 7]. The GRP is bordered by a second, bilaterally symmetrical Nodal expression domain [8]. Here we identify the Nodal inhibitor Coco as a critical target of flow. Coco and Xenopus Nodal-related 1 (Xnr1) are coexpressed in the lateralmost ciliated GRP cells. Coco becomes downregulated on the left side of the GRP as a direct readout of flow. Ablation of flow prevented Coco repression, whereas Xnr1 expression was independent of flow. Loss of flow-induced laterality defects were rescued by knockdown of Coco on the left side. Parallel knockdown of Coco and Xnr1 in GRP cells restored laterality defects in flow-impaired embryos, demonstrating that Coco acted through GRP-expressed Xnr1. Coco thus acts as a critical target of flow, suggesting that symmetry is broken by flow-mediated left-asymmetric release of Nodal repression at the midline.
A quasi-static polynomial nodal method for nuclear reactor analysis
Gehin, J.C.
Modern nodal methods are currently available which can accurately and efficiently solve the static and transient neutron diffusion equations. Most of the methods, however, are limited to two energy groups for practical application. The objective of this research is the development of a static and transient, multidimensional nodal method which allows more than two energy groups and uses a non-linear iterative method for efficient solution of the nodal equations. For both the static and transient methods, finite-difference equations which are corrected by the use of discontinuity factors are derived. The discontinuity factors are computed from a polynomial nodal method using a non-linear iteration technique. The polynomial nodal method is based upon a quartic approximation and utilizes a quadratic transverse-leakage approximation. The solution of the time-dependent equations is performed by the use of a quasi-static method in which the node-averaged fluxes are factored into shape and amplitude functions. The application of the quasi-static polynomial method to several benchmark problems demonstrates that the accuracy is consistent with that of other nodal methods. The use of the quasi-static method is shown to substantially reduce the computation time over the traditional fully-implicit time-integration method. Problems involving thermal-hydraulic feedback are accurately, and efficiently, solved by performing several reactivity/thermal-hydraulic updates per shape calculation.
The 18.6-year lunar nodal cycle and surface temperature variability in the northeast Pacific
NASA Astrophysics Data System (ADS)
McKinnell, Stewart M.; Crawford, William R.
The 18.6-year lunar nodal cycle (LNC) is a significant feature of winter (January) air and sea temperatures along the North American west coast over a 400-year period. Yet much of the recent temperature variation can also be explained by wind patterns associated with the PNA teleconnection. At Sitka, Alaska, (57°N) and nearby stations in northern British Columbia, the January PNA index accounts for over 70% of average January air temperatures in lengthy meteorological records. It appears that the LNC signal in January air temperatures in this region is not independent of the PNA, but is a component of it. The Sitka air temperature record, along with SSTs along the British Columbia coast and the PNA index have significant cross-correlations with the LNC that appear at a 2-year lag, LNC leading. The influence of the PNA pattern declines in winter with decreasing latitude but the LNC component does not. It appears as a significant feature of long-term SST variation at Scripps Pier and the California Current System. The LNC also appears over centennial-scales in proxy temperatures along western North America. The linkage of LNC-moderated surface temperatures to processes involving basin-scale teleconnections expands the possibility that the proximate mechanism may be located remotely from its expression in the northeast Pacific. Some of the largest potential sources of a diurnal tidal signal in the atmosphere are located in the western Pacific; the Sea of Okhotsk and the Indonesian archipelago.
TGF-β promotes glioma cell growth via activating Nodal expression through Smad and ERK1/2 pathways
Sun, Jing; Liu, Su-zhi; Lin, Yan; Cao, Xiao-pan; Liu, Jia-ming
Highlights: •TGF-β promoted Nodal expression in glioma cells. •TGF-β promoted Nodal expression via activating Smad and ERK1/2 pathways. •TGF-β promotes glioma cell growth via activating Nodal expression. -- Abstract: While there were certain studies focusing on the mechanism of TGF-β promoting the growth of glioma cells, the present work revealed another novel mechanism that TGF-β may promote glioma cell growth via enhancing Nodal expression. Our results showed that Nodal expression was significantly upregulated in glioma cells when TGF-β was added, whereas the TGF-β-induced Nodal expression was evidently inhibited by transfection Smad2 or Smad3 siRNAs, and the suppression was especially significant when the Smad3 was downregulated. Another, the attenuation of TGF-β-induced Nodal expression was observed with blockade of the ERK1/2 pathway also. Further detection of the proliferation, apoptosis, and invasion of glioma cells indicated that Nodal overexpression promoted the proliferation and invasion of tumor cells and inhibited their apoptosis, resembling the effect of TGF-β addition. Downregulation of Nodal expression via transfection Nodal-specific siRNA in the presence of TGF-β weakened the promoting effect of the latter on glioma cells growth, and transfecting Nodal siRNA alone in the absence of exogenous TGF-β more profoundly inhibited the growth of glioma cells. These results demonstrated that while both TGF-β and Nodal promoted glioma cells growth, the former might exert such effect by enhancing Nodal expression, which may form a new target for glioma therapy.
A Monte Carlo based nodal diffusion model for criticality analysis, and, Application of high-order cross section homogenization method to two-group nodal diffusion
NASA Astrophysics Data System (ADS)
Ilas, Germina
In the first part, an accurate and fast computational method is presented as an alternative to the Monte Carlo or deterministic transport theory codes currently used to determine the subcriticality of spent fuel storage lattices. The method is capable of analyzing storage configurations with simple or complex lattice cell geometry. It is developed based on two-group nodal diffusion theory, with the nodal cross sections and discontinuity factors determined from continuous-energy Monte Carlo simulations of each unique node (spent fuel assembly type). Three different approaches are developed to estimate the node-averaged diffusion coefficient. The applicability and the accuracy of the nodal method are assessed in two-dimensional geometry through several benchmark configurations typical at Savannah River Site. It is shown that the multiplication constant of the analyzed configurations is within 1% of the MCNP results. In the second part, the high-order cross section homogenization method, recently developed by McKinley and Rahnema, is implemented in the context of two-group nodal diffusion theory. The method corrects the generalized equivalence theory homogenization parameters for the effect of the core environment. The reconstructed fine-mesh (fuel pin) flux and power distributions are a natural byproduct of this method. The method was not tested for multigroup problems, where it was assumed that the multigroup flux expansion in terms of the perturbation parameter is a convergent series. Here the applicability of the method to two-group problems is studied, and it is shown that the perturbation expansion series converges for the multigroup case. A two-group nodal diffusion code with a bilinear intra-nodal flux shape is developed for the implementation of the high-order homogenization method in the context of the generalized equivalence theory. The method is tested by using as a benchmark a core configuration typical of a BWR in slab geometry, which has large
Extra-nodal extension is a significant prognostic factor in lymph node positive breast cancer
Aziz, Sura; Wik, Elisabeth; Davidsen, Benedicte; Aas, Hans; Aas, Turid; Akslen, Lars A.
Presence of lymph node (LN) metastasis is a strong prognostic factor in breast cancer, whereas the importance of extra-nodal extension and other nodal tumor features have not yet been fully recognized. Here, we examined microscopic features of lymph node metastases and their prognostic value in a population-based cohort of node positive breast cancer (n = 218), as part of the prospective Norwegian Breast Cancer Screening Program NBCSP (1996–2009). Sections were reviewed for the largest metastatic tumor diameter (TD-MET), nodal afferent and efferent vascular invasion (AVI and EVI), extra-nodal extension (ENE), number of ENE foci, as well as circumferential (CD-ENE) and perpendicular (PD-ENE) diameter of extra-nodal growth. Number of positive lymph nodes, EVI, and PD-ENE were significantly increased with larger primary tumor (PT) diameter. Univariate survival analysis showed that several features of nodal metastases were associated with disease-free (DFS) or breast cancer specific survival (BCSS). Multivariate analysis demonstrated an independent prognostic value of PD-ENE (with 3 mm as cut-off value) in predicting DFS and BCSS, along with number of positive nodes and histologic grade of the primary tumor (for DFS: P = 0.01, P = 0.02, P = 0.01, respectively; for BCSS: P = 0.02, P = 0.008, P = 0.02, respectively). To conclude, the extent of ENE by its perpendicular diameter was independently prognostic and should be considered in line with nodal tumor burden in treatment decisions of node positive breast cancer. PMID:28199370
The Intensity of Primary Care for Heart Failure Patients: A Determinant of Readmissions? The CarPaths Study: A French Region-Wide Analysis
Solecki, Kamila; Papinaud, Laurence; Georgescu, Vera; Roubille, François; Mercier, Gregoire
Background We aimed to classify patients with heart failure (HF) by the style of primary care they receive. Methods and Results We used the claim data (SNIIRAM: Système National d'Information Inter-Régime de l'Assurance Maladie) of patients living in a French region. We evaluated three concepts. First, baseline clinical status with age and Charlson index. Second, primary care practice style with mean delay between consultations, quantity of nursing care, and variability of diuretic dose. Third, clinical outcomes with death during follow-up, readmission for HF, and rate of unforeseen consultations. The baseline clinical status and the clinical outcomes were included to give an insight in the reasons for, and performance of, primary care practice style. Patients were classified using a hierarchical ascending classification based on principal components. A total of 2,751 patients were included in this study and were followed for a median of 22 months. The mean age was 78 y (SD: 12); 484 (18%) died, and 818 (30%) were readmitted for HF. We found three different significant groups characterized by their need for care and the intensity of practice style: group 1 (N = 734) was "low need-low intensity"; group 2 (N = 1,060) was "high need-low intensity"; and group 3 (N = 957) was "high need-high intensity". Their readmission rates were 17%, 41% and 28%, respectively. Conclusions This study evaluated the link between primary care, clinical status and main clinical outcomes in HF patients. In higher need patients, a low-intensity practice style was associated with poorer clinical outcomes. PMID:27727296
Nodal signaling activates the Smad2/3 pathway to regulate stem cell-like properties in breast cancer cells
Gong, Wenchen; Sun, Baocun; Sun, Huizhi; Zhao, Xiulan; Zhang, Danfang; Liu, Tieju; Zhao, Nan; Gu, Qiang; Dong, Xueyi; Liu, Fang
Nodal signaling plays several vital roles in the embryogenesis process. However, its reexpression in breast cancer is correlated with cancer progression, metastasis and poor prognosis. Recently, Nodal has also been reported to regulate self-renewal capacity in pancreatic cancer. This study aimed to explore the role of Nodal in breast cancer stem cells (BCSCs) and the underlying mechanisms. Therefore, the immunohistochemistry staining of Nodal in 135 human breast cancer cases was performed to analyzed the relationship of Nodal signaling, clinical outcomes and BCSC marker. And the results showed that high Nodal expression was positively correlated with poor prognosis and BCSC marker expression in breast cancer samples. We further assessed the effects of Nodal in regulating the BCSC properties in breast cancer cell lines and xenografts. Then, SB431542 was administered in vitro and in vivo to explore the function of the Smad2/3 pathway. And we demonstrated that Nodal signaling up-regulated the expression of ALDH1, CD44, CD133, Sox2, Oct4 and Nanog by activating the Smad2/3 pathway, thereby enhancing the tumorigenicity and sphere-forming ability of breast cancer cells. Furthermore, treatment with SB431542 could inhibit the properties of BCSCs in vitro and in vivo. In conclusion, these findings indicate that Nodal signaling may play a vital role in maintaining the BCSC phenotype in breast cancer and serve as a potential target to explore BCSC-specific therapies.
Topological nodal-line fermions in spin-orbit metal PbTaSe2
Bian, Guang; Chang, Tay-Rong; Sankar, Raman; Xu, Su-Yang; Zheng, Hao; Neupert, Titus; Chiu, Ching-Kai; Huang, Shin-Ming; Chang, Guoqing; Belopolski, Ilya; Sanchez, Daniel S.; Neupane, Madhab; Alidoust, Nasser; Liu, Chang; Wang, BaoKai; Lee, Chi-Cheng; Jeng, Horng-Tay; Zhang, Chenglong; Yuan, Zhujun; Jia, Shuang; Bansil, Arun; Chou, Fangcheng; Lin, Hsin; Hasan, M. Zahid
Topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe2 are not only protected by the reflection symmetry but also characterized by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems. PMID:26829889
Role of Nodal-PITX2C signaling pathway in glucose-induced cardiomyocyte hypertrophy.
Su, Dongmei; Jing, Sun; Guan, Lina; Li, Qian; Zhang, Huiling; Gao, Xiaobo; Ma, Xu
Pathological cardiac hypertrophy is a major cause of morbidity and mortality in cardiovascular disease. Recent studies have shown that cardiomyocytes, in response to high glucose (HG) stimuli, undergo hypertrophic growth. While much work still needs to be done to elucidate this important mechanism of hypertrophy, previous works have showed that some pathways or genes play important roles in hypertrophy. In this study, we showed that sublethal concentrations of glucose (25 mmol/L) could induce cardiomyocyte hypertrophy with an increase in the cellular surface area and the upregulation of the atrial natriuretic peptide (ANP) gene, a hypertrophic marker. High glucose (HG) treatments resulted in the upregulation of the Nodal gene, which is under-expressed in cardiomyocytes. We also determined that the knockdown of the Nodal gene resisted HG-induced cardiomyocyte hypertrophy. The overexpression of Nodal was able to induce hypertrophy in cardiomyocytes, which was associated with the upregulation of the PITX2C gene. We also showed that increases in the PITX2C expression, in response to Nodal, were mediated by the Smad4 signaling pathway. This study is highly relevant to the understanding of the effects of the Nodal-PITX2C pathway on HG-induced cardiomyocyte hypertrophy, as well as the related molecular mechanisms.
Topological nodal-line fermions in spin-orbit metal PbTaSe2
Bian, Guang; Chang, Tay-Rong; Sankar, Raman; Xu, Su-Yang; Zheng, Hao; Neupert, Titus; Chiu, Ching-Kai; Huang, Shin-Ming; Chang, Guoqing; Belopolski, Ilya; Sanchez, Daniel S.; Neupane, Madhab; Alidoust, Nasser; Liu, Chang; Wang, BaoKai; Lee, Chi-Cheng; Jeng, Horng-Tay; Zhang, Chenglong; Yuan, Zhujun; Jia, Shuang; Bansil, Arun; Chou, Fangcheng; Lin, Hsin; Hasan, M. Zahid
Here we discuss how topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe2 are not only protected by the reflection symmetry but also characterized by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems.
Topological nodal-line fermions in spin-orbit metal PbTaSe2
Bian, Guang; Chang, Tay-Rong; Sankar, Raman; ...
Here we discuss how topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe2 are not only protected by the reflection symmetry but also characterizedmore » by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems.« less
The impact of surgical technique on neck dissection nodal yield: making a difference.
Lörincz, Balazs B; Langwieder, Felix; Möckelmann, Nikolaus; Sehner, Susanne; Knecht, Rainald
The nodal yield of neck dissections is an independent prognostic factor in several types of head and neck cancer. The authors aimed to determine whether the applied dissection technique has a significant impact on nodal yield. This is a single-institution, prospective study with internal control group (level of evidence: 2A). Data of 150 patients undergoing 223 neck dissections between February 2011 and March 2013 have been collected in a comprehensive cancer centre. Eighty-two patients underwent neck dissection with unwrapping the cervical fascia from lateral to medial, while 68 patients were operated without specifically unwrapping the fascia, in a caudal to cranial fashion. The standardised, horizontal neck dissection technique along the fascial planes resulted in a significantly higher nodal count in Levels I, II, III and IV, as well as in terms of overall nodal yield (mean: n = 22.53) than that of the vertical dissection applied in the control group (mean: n = 15.00). This is the first publication showing a direct correlation between neck dissection nodal yield and surgical technique. Therefore, it is paramount to optimise the applied surgical concept to maximise the oncological benefit.
Activin/Nodal Signaling Supports Retinal Progenitor Specification in a Narrow Time Window during Pluripotent Stem Cell Neuralization
Bertacchi, Michele; Lupo, Giuseppe; Pandolfini, Luca; Casarosa, Simona; D'Onofrio, Mara; Pedersen, Roger A.; Harris, William A.; Cremisi, Federico
Summary Retinal progenitors are initially found in the anterior neural plate region known as the eye field, whereas neighboring areas undertake telencephalic or hypothalamic development. Eye field cells become specified by switching on a network of eye field transcription factors, but the extracellular cues activating this network remain unclear. In this study, we used chemically defined media to induce in vitro differentiation of mouse embryonic stem cells (ESCs) toward eye field fates. Inhibition of Wnt/β-catenin signaling was sufficient to drive ESCs to telencephalic, but not retinal, fates. Instead, retinal progenitors could be generated from competent differentiating mouse ESCs by activation of Activin/Nodal signaling within a narrow temporal window corresponding to the emergence of primitive anterior neural progenitors. Activin also promoted eye field gene expression in differentiating human ESCs. Our results reveal insights into the mechanisms of eye field specification and open new avenues toward the generation of retinal progenitors for translational medicine. PMID:26388287
... Dialysis or Transplant Paying for Kidney Failure Treatment Contact Us Health Information Center Phone: 1-800-860- ... to share this content freely. October 2, 2013 Contact Us Health Information Center Phone: 1-800-860- ...
... for people who can't tolerate ACE inhibitors. Beta blockers. This class of drugs not only slows your ... rhythms and lessen your chance of dying unexpectedly. Beta blockers may reduce signs and symptoms of heart failure, ...
Ten-Year Locoregional Recurrence Risks in Women With Nodal Micrometastatic Breast Cancer Staged With Axillary Dissection
Lupe, Krystine; Truong, Pauline T.; Alexander, Cheryl; Speers, Caroline; Tyldesley, Scott
Purpose: To compare the locoregional recurrence (LRR) rates in patients with nodal mirometastases (pNmic) with those in patients with node-negative (pN0) and macroscopic node-positive (pNmac) breast cancer; and to evaluate the LRR rates according to locoregional treatment of pNmic disease. Methods and Materials: The subjects were 9,616 women diagnosed between 1989 and 1999 with Stage pT1-T2, pN0, pNmic, or pNmac, M0 breast cancer. All women had undergone axillary dissection. The Kaplan-Meier local recurrence, regional recurrence, and LRR rates were compared among those with pN0 (n = 7,977), pNmic (n = 490) and pNmac (n = 1,149) and according to locoregional treatment. Multivariate analysis was performed to identify the significant factors associated with LRR. Results: The median follow-up was 11 years. The 10-year Kaplan-Meier recurrence rate in the pN0, pNmic, and pNmac cohorts was 6.1%, 6.8%, and 8.7% for local recurrence; 3.1%, 6.2%, and 10.3% for regional recurrence; and 8.0%, 11.6%, and 15.2% for LRR, respectively (all p < .001). In the pNmic patients, the 10-year regional recurrence rate was 6.4% with breast-conserving surgery plus breast radiotherapy (RT), 5.4% with breast-conserving surgery plus locoregional RT, 4.6% with mastectomy alone, 11.1% with mastectomy plus chest wall RT, and 10.7% with mastectomy plus locoregional RT. In patients with pNmic disease and age <45 years, Grade 3 histologic features, lymphovascular invasion, nodal ratio >0.25, and estrogen receptor-negative disease, the 10-year LRR rates were 15-20%. On multivariate analysis of the entire cohort, pNmic was associated with greater LRR than Stage pN0 (hazard ratio [HR], 1.6; p = .002). On multivariate analysis of pNmic patients only, age <45 years was associated with significantly greater LRR (HR, 1.9; p = .03), and trends for greater LRR were observed with a nodal ratio >0.25 (HR, 2.0; p = .07) and lymphovascular invasion (HR, 1.7; p = .07). Conclusion: Women with pNmic had a greater
Interaction of pupil offset and fifth-order nodal aberration field properties in rotationally symmetric telescopes.
Hu, Haili; Liu, Jianjun; Fan, Zhigang
In this paper we succeeded in deriving changes in the nodal positions of aberrations that belong to the fifth-order class in pupil dependence by applying a system level pupil decentration vector. Our treatment is specifically for rotationally symmetric multi-mirror optical designs that simply use an offset pupil as a means of creating an unobscured optical design. When the pupil is offset, only the vectors to determine the node locations are modified by the pupil decentration vector, while the nodal properties originally developed for titled/decentered optical systems are retained. In general, the modifications to the nodal vectors for any particular aberration type are contributed only by terms of higher order pupil dependence.
Topological nodal line semimetals in the CaP3 family of materials
NASA Astrophysics Data System (ADS)
Xu, Qiunan; Yu, Rui; Fang, Zhong; Dai, Xi; Weng, Hongming
By using first-principles calculations and a k .p model analysis, we propose that the three-dimensional topological nodal line semimetal state can be realized in the CaP3 family of materials, which includes CaP3,CaAs3,SrP3,SrAs3, and BaAs3, when spin-orbit coupling (SOC) is ignored. The closed topological nodal line near the Fermi energy is protected by time reversal symmetry and spatial inversion symmetry. Moreover, drumheadlike two-dimensional surface states are also obtained on the c -direction surface of these materials. When SOC is included, the gaps open along the nodal line and these materials become strong topological insulators with Z2 indices as (1 ;010 ) .
Potential for Infra-Nodal Heart Block and Cardiogenic Shock With Propofol Administration
Olson, Nicholas; Lim, Michael J.; Ferreira, Scott W.; Mehdirad, Ali A.
We report a case of infra-nodal complete heart block and cardiogenic shock in a previously healthy 64-year-old man after administration of 180 mg of intravenous Propofol. Although bradycardia, hypotension, and heart block are commonly seen with propofol administration, such findings are transient and respond quickly to administration of vagolytic or sympathomimetic agents suggesting an AV nodal mechanism of heart block. Sustained left ventricular systolic dysfunction and cardiogenic shock by an alternative, non-autonomic mechanism has also been described in the setting of Propofol administration. Our case is the first to note sustained complete infra-nodal heart block in this setting. Early recognition of such a complication, restoration of atrio-ventricular (A-V) synchrony with dual chamber pacing, and aggressive circulatory support is essential in bridging such patients to recovery.
Doping-Dependent Nodal Fermi Velocity in Bi-2212 Revealed by High-Resolution ARPES
Vishik, I. M.
The improved resolution of laser-based angle-resolved photoemission spectroscopy (ARPES) allows reliable access to fine structures in the spectrum. We present a systematic, doping-dependent study of a recently discovered low-energy kink in the nodal dispersion of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} (Bi-2212), which demonstrates the ubiquity and robustness of this kink in underdoped Bi-2212. The renormalization of the nodal velocity due to this kink becomes stronger with underdoping, revealing that the nodal Fermi velocity is non-universal, in contrast to assumed phenomenology. This is used together with laser-ARPES measurements of the gap velocity, v{sub 2}, to resolve discrepancies with thermal conductivity measurements.
Introduction Heart failure occurs in 3% to 4% of adults aged over 65 years, usually as a consequence of coronary artery disease or hypertension, and causes breathlessness, effort intolerance, fluid retention, and increased mortality. The 5-year mortality in people with systolic heart failure ranges from 25% to 75%, often owing to sudden death following ventricular arrhythmia. Risks of cardiovascular events are increased in people with left ventricular systolic dysfunction (LVSD) or heart failure. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of multidisciplinary interventions for heart failure? What are the effects of exercise in people with heart failure? What are the effects of drug treatments for heart failure? What are the effects of devices for treatment of heart failure? What are the effects of coronary revascularisation for treatment of heart failure? What are the effects of drug treatments in people at high risk of heart failure? What are the effects of treatments for diastolic heart failure? We searched: Medline, Embase, The Cochrane Library, and other important databases up to August 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 80 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: aldosterone receptor antagonists, amiodarone, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, anticoagulation, antiplatelet agents, beta-blockers, calcium
The 18.6 yr nodal modulation in the tides of Southern European coasts
NASA Astrophysics Data System (ADS)
Shaw, A. G. P.; Tsimplis, M. N.
The nodal modulation of the diurnal ( K1 and O1) and semi-diurnal ( M2 and K2) tidal constituents at the coasts of the Mediterranean Sea and the eastern Atlantic is estimated and its spatial variability mapped. Fourteen hourly tide gauge records each spanning more than 18 years are considered in this analysis. Ten tide gauges are located in the Mediterranean Sea and four in the Bay of Biscay. The nodal modulation of the most energetic tidal constituent ( M2) reaches up to 5 cm at the eastern Atlantic coasts, while within the Mediterranean Sea its modulation is in general less than 1.1 cm. The largest K2 nodal modulation found is 3.7 cm in the eastern Atlantic coasts. In the Mediterranean Sea, smaller modulation amplitudes, ranging between 0.4 and 1.4 cm are found. The K1 tide constituent has the largest amplitude nodal modulation within the Mediterranean Sea of 1.9 cm in the north Adriatic Sea, which is also larger than the modulation of this constituent at the eastern Atlantic coasts. The O1 tide constituent has the highest amplitude nodal modulation (1.4 cm) at the eastern Atlantic coasts. In the Mediterranean Sea the maximum value is 1 cm in the north Adriatic Sea. The derived nodal modulations of the diurnal and semi-diurnal constituents follow, in general, the equilibrium tidal theory. The tidal amplitudes for all four components do not indicate significant secular trends for most tide gauges. The tidal phases indicate significant negative trends for all four tidal constituents within the central and eastern Mediterranean Sea.
A predictive index of axillary nodal involvement in operable breast cancer.
De Laurentiis, M.; Gallo, C.; De Placido, S.; Perrone, F.; Pettinato, G.; Petrella, G.; Carlomagno, C.; Panico, L.; Delrio, P.; Bianco, A. R.
We investigated the association between pathological characteristics of primary breast cancer and degree of axillary nodal involvement and obtained a predictive index of the latter from the former. In 2076 cases, 17 histological features, including primary tumour and local invasion variables, were recorded. The whole sample was randomly split in a training (75% of cases) and a test sample. Simple and multiple correspondence analysis were used to select the variables to enter in a multinomial logit model to build an index predictive of the degree of nodal involvement. The response variable was axillary nodal status coded in four classes (N0, N1-3, N4-9, N > or = 10). The predictive index was then evaluated by testing goodness-of-fit and classification accuracy. Covariates significantly associated with nodal status were tumour size (P < 0.0001), tumour type (P < 0.0001), type of border (P = 0.048), multicentricity (P = 0.003), invasion of lymphatic and blood vessels (P < 0.0001) and nipple invasion (P = 0.006). Goodness-of-fit was validated by high concordance between observed and expected number of cases in each decile of predicted probability in both training and test samples. Classification accuracy analysis showed that true node-positive cases were well recognised (84.5%), but there was no clear distinction among the classes of node-positive cases. However, 10 year survival analysis showed a superimposible prognostic behaviour between predicted and observed nodal classes. Moreover, misclassified node-negative patients (i.e. those who are predicted positive) showed an outcome closer to patients with 1-3 metastatic nodes than to node-negative ones. In conclusion, the index cannot completely substitute for axillary node information, but it is a predictor of prognosis as accurate as nodal involvement and identifies a subgroup of node-negative patients with unfavourable prognosis. PMID:8630286
Melanocytes Affect Nodal Expression and Signaling in Melanoma Cells: A Lesson from Pediatric Large Congenital Melanocytic Nevi.
Margaryan, Naira V; Gilgur, Alina; Seftor, Elisabeth A; Purnell, Chad; Arva, Nicoleta C; Gosain, Arun K; Hendrix, Mary J C; Strizzi, Luigi
Expression of Nodal, a Transforming Growth Factor-beta (TGF-β) related growth factor, is associated with aggressive melanoma. Nodal expression in adult dysplastic nevi may predict the development of aggressive melanoma in some patients. A subset of pediatric patients diagnosed with giant or large congenital melanocytic nevi (LCMN) has shown increased risk for development of melanoma. Here, we investigate whether Nodal expression can help identify the rare cases of LCMN that develop melanoma and shed light on why the majority of these patients do not. Immunohistochemistry (IHC) staining results show varying degree of Nodal expression in pediatric dysplastic nevi and LCMN. Moreover, median scores from Nodal IHC expression analysis were not significantly different between these two groups. Additionally, none of the LCMN patients in this study developed melanoma, regardless of Nodal IHC levels. Co-culture experiments revealed reduced tumor growth and lower levels of Nodal and its signaling molecules P-SMAD2 and P-ERK1/2 when melanoma cells were grown in vivo or in vitro with normal melanocytes. The same was observed in melanoma cells cultured with melanocyte conditioned media containing pigmented melanocyte derived melanosomes (MDM). Since MDM contain molecules capable of inactivating radical oxygen species, to investigate potential anti-oxidant effect of MDM on Nodal expression and signaling in melanoma, melanoma cells were treated with either N-acetyl-l-cysteine (NAC), a component of the anti-oxidant glutathione or synthetic melanin, which in addition to providing pigmentation can also exert free radical scavenging activity. Melanoma cells treated with NAC or synthetic melanin showed reduced levels of Nodal, P-SMAD2 and P-ERK1/2 compared to untreated melanoma cells. Thus, the potential role for Nodal in melanoma development in LCMN is less evident than in adult dysplastic nevi possibly due to melanocyte cross-talk in LCMN capable of offsetting or delaying the pro
On bistable phasing of 18.6 year nodal induced flood in India
NASA Astrophysics Data System (ADS)
Currie, Robert G.
In agreement with Campbell (1983), Flood Area Indices (FAI) for India are interpreted as being modulated by tidal forcing at the 18.6 yr lunar nodal period. There is evidence maximum flood was approximately out of phase with nodal epoch 1898.9 whereas at epochs 1917.5, 1936,1, 1954.7, and 1973.3 maximum flood was approximately in phase. This interpretation implies that India should be experiencing widespread dryness in an interval ±2 to 3 years centered at mid-epoch 1982.6.
Nodal superconductivity in FeS: Evidence from quasiparticle heat transport
NASA Astrophysics Data System (ADS)
Ying, T. P.; Lai, X. F.; Hong, X. C.; Xu, Y.; He, L. P.; Zhang, J.; Wang, M. X.; Yu, Y. J.; Huang, F. Q.; Li, S. Y.
We report low-temperature heat transport measurements on superconducting iron sulfide FeS with Tc≈5 K, which has the same crystal structure and similar electronic band structure to the superconducting iron selenide FeSe. In zero magnetic field, a significant residual linear term κ0/T is observed. At low field, κ0/T increases rapidly with increasing field. These results suggest a nodal superconducting gap in FeS. We compare it with the sister compound FeSe and other iron-based superconductors with nodal gaps.
The Impact of Preradiation Residual Disease Volume on Time to Locoregional Failure in Cutaneous Merkel Cell Carcinoma—A TROG Substudy
Finnigan, Renee; Hruby, George; Wratten, Chris; Keller, Jacqui; Tripcony, Lee; Dickie, Graeme; Rischin, Danny; Poulsen, Michael
Purpose: This study evaluated the impact of margin status and gross residual disease in patients treated with chemoradiation therapy for high-risk stage I and II Merkel cell cancer (MCC). Methods and Materials: Data were pooled from 3 prospective trials in which patients were treated with 50 Gy in 25 fractions to the primary lesion and draining lymph nodes and 2 schedules of carboplatin based chemotherapy. Time to locoregional failure was analyzed according to the burden of disease at the time of radiation therapy, comparing patients with negative margins, involved margins, or macroscopic disease. Results: Analysis was performed on 88 patients, of whom 9 had microscopically positive resection margins and 26 had macroscopic residual disease. The majority of gross disease was confined to nodal regions. The 5-year time to locoregional failure, time to distant failure, time to progression, and disease-specific survival rates for the whole group were 73%, 69%, 62%, and 66% respectively. The hazard ratio for macroscopic disease at the primary site or the nodes was 1.25 (95% confidence interval 0.57-2.77), P=.58. Conclusions: No statistically significant differences in time to locoregional failure were identified between patients with negative margins and those with microscopic or gross residual disease. These results must, however, be interpreted with caution because of the limited sample size.
Patterns of Local-Regional Failure in Completely Resected Stage IIIA(N2) Non-Small Cell Lung Cancer Cases: Implications for Postoperative Radiation Therapy Clinical Target Volume Design
Feng, Wen; Fu, Xiao-Long; Cai, Xu-Wei; Yang, Huan-Jun; Wu, Kai-Liang; Fan, Min; Xiang, Jia-Qing; Zhang, Ya-Wei; Chen, Hai-Quan
Purpose: To analyze patterns of local-regional failure (LRF) for completely resected stage IIIA(N2) non-small cell lung cancer (NSCLC) patients treated in our hospital and to propose a clinical target volume (CTV) for postoperative radiation therapy (PORT) in these patients. Methods and Materials: From 2005 to 2011, consecutive patients with pT1-3N2 NSCLC who underwent complete resection in our hospital but who did not receive PORT were identified. The patterns of first LRF were assessed and evaluated as to whether these areas would be encompassed by our proposed PORT CTV. Results: With a median follow-up of 24 months, 173 of 250 patients (69.2%) experienced disease recurrence. Of the 54 patients with LRF as the first event, 48 (89%) had recurrence within the proposed PORT CTV, and 6 (11%) had failures occurring both within and outside the proposed CTV (all of which occurred in patients with right-lung cancer). Ninety-three percent of failure sites (104 of 112) would have been contained within the proposed PORT CTV. For left-sided lung cancer, the most common lymph node station failure site was 4R, followed by 7, 4L, 6, 10L, and 5. For right-sided lung cancer, the most common site was station 2R, followed by 10R, 4R, and 7. Conclusions: LRF following complete surgery was an important and potentially preventable pattern of failure in stage IIIA(N2) patients. Ipsilateral superior mediastinal recurrences dominated for right-sided tumors, whereas left-sided tumors frequently involved the bilateral superior mediastinum. Most of the LRF sites would have been covered by the proposed PORT CTV. A prospective investigation of patterns of failure after PORT (following our proposed CTV delineation guideline) is presently underway and will be reported in a separate analysis.
Nodal Quasiparticle Meltdown in Ultra-High Resolution Pump-Probe Angle-Resolved Photoemission
Graf, Jeff; Jozwiak, Chris; Smallwood, Chris L.; Eisaki, H.; Kaindl, Robert A.; Lee, Dung-Hai; Lanzara, Alessandra
High-T{sub c} cuprate superconductors are characterized by a strong momentum-dependent anisotropy between the low energy excitations along the Brillouin zone diagonal (nodal direction) and those along the Brillouin zone face (antinodal direction). Most obvious is the d-wave superconducting gap, with the largest magnitude found in the antinodal direction and no gap in the nodal direction. Additionally, while antin- odal quasiparticle excitations appear only below T{sub c}, superconductivity is thought to be indifferent to nodal excitations as they are regarded robust and insensitive to T{sub c}. Here we reveal an unexpected tie between nodal quasiparticles and superconductivity using high resolution time- and angle-resolved photoemission on optimally doped Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} . We observe a suppression of the nodal quasiparticle spectral weight following pump laser excitation and measure its recovery dynamics. This suppression is dramatically enhanced in the superconducting state. These results reduce the nodal-antinodal dichotomy and challenge the conventional view of nodal excitation neutrality in superconductivity. The electronic structures of high-Tc cuprates are strongly momentum-dependent. This is one reason why the momentum-resolved technique of angle-resolved photoemission spectroscopy (ARPES) has been a central tool in the field of high-temperature superconductivity. For example, coherent low energy excitations with momenta near the Brillouin zone face, or antinodal quasiparticles (QPs), are only observed below T{sub c} and have been linked to superfluid density. They have therefore been the primary focus of ARPES studies. In contrast, nodal QPs, with momenta along the Brillouin zone diagonal, have received less attention and are usually regarded as largely immune to the superconducting transition because they seem insensitive to perturbations such as disorder, doping, isotope exchange, charge ordering, and temperature. Clearly
Introduction Heart failure occurs in 3% to 4% of adults aged over 65 years, usually as a consequence of coronary artery disease or hypertension, and causes breathlessness, effort intolerance, fluid retention, and increased mortality. The 5-year mortality in people with systolic heart failure ranges from 25% to 75%, often owing to sudden death following ventricular arrhythmia. Risks of cardiovascular events are increased in people with left ventricular systolic dysfunction (LVSD) or heart failure. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of non-drug treatments, and of drug and invasive treatments, for heart failure? What are the effects of angiotensin-converting enzyme inhibitors in people at high risk of heart failure? What are the effects of treatments for diastolic heart failure? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 85 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: aldosterone receptor antagonists, amiodarone, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, anticoagulation, antiplatelet agents, beta-blockers, calcium channel blockers, cardiac resynchronisation therapy, digoxin (in people already receiving diuretics and angiotensin-converting enzyme inhibitors), exercise, hydralazine plus isosorbide dinitrate, implantable cardiac
... News Physician Resources Professions Site Index A-Z Kidney Failure Kidney failure, also known as renal failure, ... evaluated? How is kidney failure treated? What is kidney (renal) failure? The kidneys are designed to maintain ...
The 18.6 yr nodal cycle and its impact on tidal sedimentation
NASA Astrophysics Data System (ADS)
Oost, A. P.; de Haas, H.; Ijnsen, F.; van den Boogert, J. M.; de Boer, P. L.
The 18.6 yr nodal cycle modulates tidal amplitudes and currents, and consequently sedimentation in tide-influenced sedimentary environments. Data are presented which show that such effects are obvious along the coast of the Dutch barrier islands and in the sedimentary fill of abandoned channels.
Nodal Analysis Optimization Based on the Use of Virtual Current Sources: A Powerful New Pedagogical Method
ERIC Educational Resources Information Center
Chatzarakis, G. E.
This paper presents a new pedagogical method for nodal analysis optimization based on the use of virtual current sources, applicable to any linear electric circuit (LEC), regardless of its complexity. The proposed method leads to straightforward solutions, mostly arrived at by inspection. Furthermore, the method is easily adapted to computer…
Precision evaluation of lens systems using a nodal slide/MTF optical bench
NASA Astrophysics Data System (ADS)
Doherty, Victor J.; Chapnik, Philip D.
A compact, self-contained production instrument designed to permit the rapid and precise performance characterization of a wide variety of lenses and optical systems has been developed by Eidolon Corporation. The Eidolon Production Nodal Slide/MTF Measurement System can be used to measure effective focal length (EFL), distortion, field curvature, chromatic aberration, spot size, and modulation transfer function (MTF).
Nodal surface approximations to the P, G, D and I-WP triply periodic minimal surfaces
NASA Astrophysics Data System (ADS)
Gandy, Paul J. F.; Bardhan, Sonny; Mackay, Alan L.; Klinowski, Jacek
The cubic P, G, D and I-WP triply periodic minimal surfaces (TPMS) may be closely approximated using periodic nodal surfaces (PNS) with few Fourier terms, thus enabling easy generation of TPMS for use in various chemical and physical applications. The accuracy of such approximations is quantitatively discussed and represented visually using a colour coding.
5-Hydroxymethylcytosine expression in metastatic melanoma versus nodal nevus in sentinel lymph node biopsies.
Lee, Jonathan J; Granter, Scott R; Laga, Alvaro C; Saavedra, Arturo P; Zhan, Qian; Guo, Weimin; Xu, Shuyun; Murphy, George F; Lian, Christine G
Sentinel lymph node biopsies are conducted to stage patients with newly diagnosed melanomas that have histopathological attributes conferring defined levels of metastatic potential. Because benign nevic cells may also form 'deposits' in lymph nodes (nodal nevus), the pathological evaluation for metastatic melanoma within sentinel lymph nodes can be challenging. Twenty-eight sentinel lymph node biopsy cases containing either metastatic melanoma (N=18) or nodal nevi (N=10) were retrieved from the archives of the Brigham and Women's Hospital, Department of Pathology (2011-2014). In addition, two sentinel lymph node cases that were favored to represent metastatic disease but whose histopathological features were viewed as equivocal, with melanoma favored, were also included. Dual labeling for the melanocyte lineage marker, MART-1, and the epigenetic marker, 5-hydroxymethylcytosine, a functionally significant indicator that has been shown to distinguish benign nevi from melanoma, was performed on all cases using immunohistochemistry and/or direct immunofluorescence. All (18 of 18) metastatic melanoma cases showed complete loss of 5-hydroxymethylcytosine nuclear staining in MART-1-positive cells, and all (10 of 10) nodal nevus cases demonstrated 5-hydroxymethylcytosine nuclear staining in MART-1-positive cells. In addition, 5-hydroxymethylcytosine staining confirmed the favored diagnoses of metastatic melanoma in the two 'equivocal' cases. Thus, 5-hydroxymethylcytosine may be a useful adjunctive marker to distinguish between benign nodal nevi and metastatic melanoma during the evaluation of sentinel lymph node biopsies for metastatic melanoma.
Nodal Green's Function Method Singular Source Term and Burnable Poison Treatment in Hexagonal Geometry
A.A. Bingham; R.M. Ferrer; A.M. ougouag
An accurate and computationally efficient two or three-dimensional neutron diffusion model will be necessary for the development, safety parameters computation, and fuel cycle analysis of a prismatic Very High Temperature Reactor (VHTR) design under Next Generation Nuclear Plant Project (NGNP). For this purpose, an analytical nodal Green's function solution for the transverse integrated neutron diffusion equation is developed in two and three-dimensional hexagonal geometry. This scheme is incorporated into HEXPEDITE, a code first developed by Fitzpatrick and Ougouag. HEXPEDITE neglects non-physical discontinuity terms that arise in the transverse leakage due to the transverse integration procedure application to hexagonal geometry and cannot account for the effects of burnable poisons across nodal boundaries. The test code being developed for this document accounts for these terms by maintaining an inventory of neutrons by using the nodal balance equation as a constraint of the neutron flux equation. The method developed in this report is intended to restore neutron conservation and increase the accuracy of the code by adding these terms to the transverse integrated flux solution and applying the nodal Green's function solution to the resulting equation to derive a semi-analytical solution.
NOKIN1D: one-dimensional neutron kinetics based on a nodal collocation method
NASA Astrophysics Data System (ADS)
Verdú, G.; Ginestar, D.; Miró, R.; Jambrina, A.; Barrachina, T.; Soler, Amparo; Concejal, Alberto
The TRAC-BF1 one-dimensional kinetic model is a formulation of the neutron diffusion equation in the two energy groups' approximation, based on the analytical nodal method (ANM). The advantage compared with a zero-dimensional kinetic model is that the axial power profile may vary with time due to thermal-hydraulic parameter changes and/or actions of the control systems but at has the disadvantages that in unusual situations it fails to converge. The nodal collocation method developed for the neutron diffusion equation and applied to the kinetics resolution of TRAC-BF1 thermal-hydraulics, is an adaptation of the traditional collocation methods for the discretization of partial differential equations, based on the development of the solution as a linear combination of analytical functions. It has chosen to use a nodal collocation method based on a development of Legendre polynomials of neutron fluxes in each cell. The qualification is carried out by the analysis of the turbine trip transient from the NEA benchmark in Peach Bottom NPP using both the original 1D kinetics implemented in TRAC-BF1 and the 1D nodal collocation method.
47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.
Code of Federal Regulations, 2010 CFR
... 47 Telecommunication 5 2010-10-01 2010-10-01 false Digital Electronic Message Service Nodal Stations. 101.503 Section 101.503 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic...
A Developmentally Based Categorization of Branching in Trifolium repens L.: Influence of Nodal Roots
This study describes the successive stages of development of branches from axillary buds in fully rooted plants of Trifolium repens grown in near optimal conditions, and the way in which this developmental pathway differs when nodal root formation is prevented as plants grow out from a rooted base. Cuttings of a single genotype were established in a glasshouse with nodal root systems on the two basal phytomers and grown on so that nodal rooting was either permitted (+R) or prevented (–R). In +R plants, axillary tissues could be assigned to one of four developmental categories: unemerged buds, emerged buds, unbranched lateral branches or secondarily branched lateral branches. In –R plants, branch development was retarded, with the retardation becoming increasingly pronounced as the number of –R phytomers on the primary stolon increased. Retarded elongation of the internodes of lateral shoots on –R plants resulted in the formation of a distinct fifth developmental category: short shoots (defined as branches with two or more leaves but with mean internode length equal to, or less than, 10 % of that of the immediately proximal internode on the parent stolon) which had reduced phytomer appearance rates but retained the potential to develop into lateral branches. Transfer of +R plants to –R conditions, and vice versa, after 66 d demonstrated that subsequent branch development was wholly under the control of the youngest nodal root present, regardless of the age and number of root systems proximal to it. PMID:12234150
Nodal Structure and Stimulus Relatedness in Equivalence Classes: Post-Class Formation Preference Tests
ERIC Educational Resources Information Center
Moss-Lourenco, Patricia; Fields, Lanny
Three experiments used postclass formation within-class preference test performances to evaluate the effects of nodal distance on the relatedness of stimuli in equivalence classes. In Experiment 1, two 2-node four-member equivalence classes were established using the simultaneous protocol in which all of the baseline relations were trained…
Photoacoustic intra-operative nodal staging using clinically approved superparamagnetic iron oxide nanoparticles
NASA Astrophysics Data System (ADS)
Grootendorst, Diederik J.; Fratila, Raluca M.; Visscher, Martijn; Ten Haken, Bennie; van Wezel, Richard; Steenbergen, Wiendelt; Manohar, Srirang; Ruers, Theo J. M.
Detection of tumor metastases in the lymphatic system is essential for accurate staging of various malignancies, however fast, accurate and cost-effective intra-operative evaluation of the nodal status remains difficult to perform with common available medical imaging techniques. In recent years, numerous studies have confirmed the additional value of superparamagnetic iron oxide dispersions (SPIOs) for nodal staging purposes, prompting the clearance of different SPIO dispersions for clinical practice. We evaluate whether a combination of photoacoustic (PA) imaging and a clinically approved SPIO dispersion, could be applied for intra-operative nodal staging. Metastatic adenocarcinoma was inoculated in Copenhagen rats for 5 or 8 days. After SPIO injection, the lymph nodes were photoacoustically imaged both in vivo and ex vivo whereafter imaging results were correlated with MR and histology. Results were compared to a control group without tumor inoculation. In the tumor groups clear irregularities, as small as 1 mm, were observed in the PA contrast pattern of the nodes together with an decrease of PA response. These irregularities could be correlated to the absence of contrast in the MR images and could be linked to metastatic deposits seen in the histological slides. The PA and MR images of the control animals did not show these features. We conclude that the combination of photoacoustic imaging with a clinically approved iron oxide nanoparticle dispersion is able to detect lymph node metastases in an animal model. This approach opens up new possibilities for fast intra-operative nodal staging in a clinical setting.
Anomalous nodal count and singularities in the dispersion relation of honeycomb graphs
NASA Astrophysics Data System (ADS)
Band, Ram; Berkolaiko, Gregory; Weyand, Tracy
We study the nodal count of the so-called bi-dendral graphs and show that it exhibits an anomaly: the nodal surplus is never equal to 0 or β, the first Betti number of the graph. According to the nodal-magnetic theorem, this means that bands of the magnetic spectrum (dispersion relation) of such graphs do not have maxima or minima at the "usual" symmetry points of the fundamental domain of the reciprocal space of magnetic parameters. In search of the missing extrema, we prove a necessary condition for a smooth critical point to happen inside the reciprocal fundamental domain. Using this condition, we identify the extrema as the singularities in the dispersion relation of the maximal Abelian cover of the graph (the honeycomb graph being an important example). In particular, our results show that the anomalous nodal count is an indication of the presence of conical points in the dispersion relation of the maximal universal cover. We also discover that the conical points are present in the dispersion relation of graphs with much less symmetry than was required in previous investigations.
Static and dynamic posterior cingulate cortex nodal topology of default mode network predicts attention task performance.
Lin, Pan; Yang, Yong; Jovicich, Jorge; De Pisapia, Nicola; Wang, Xiang; Zuo, Chun S; Levitt, James Jonathan
Characterization of the default mode network (DMN) as a complex network of functionally interacting dynamic systems has received great interest for the study of DMN neural mechanisms. In particular, understanding the relationship of intrinsic resting-state DMN brain network with cognitive behaviors is an important issue in healthy cognition and mental disorders. However, it is still unclear how DMN functional connectivity links to cognitive behaviors during resting-state. In this study, we hypothesize that static and dynamic DMN nodal topology is associated with upcoming cognitive task performance. We used graph theory analysis in order to understand better the relationship between the DMN functional connectivity and cognitive behavior during resting-state and task performance. Nodal degree of the DMN was calculated as a metric of network topology. We found that the static and dynamic posterior cingulate cortex (PCC) nodal degree within the DMN was associated with task performance (Reaction Time). Our results show that the core node PCC nodal degree within the DMN was significantly correlated with reaction time, which suggests that the PCC plays a key role in supporting cognitive function.
Partial Unroofed Coronary Sinus Associated With Upper Septal Ventricular Tachycardia and Atrioventricular Nodal Reentrant Tachycardia
Bohora, Shomu; Singh, Parvindar; Shah, Kaushal
A 58 year old gentleman with complaints of palpitations and documented tachycardia was found to have a dilated right atrium, right ventricle and coronary sinus, which were due to partial unroofed coronary sinus without a left superior vena cava. He had upper septal ventricular tachycardia and atrio-ventricular nodal reentrant tachycardia, which was successfully treated by radiofrequency ablation. PMID:25852246
Analysis of nodal aberration properties in off-axis freeform system design.
Shi, Haodong; Jiang, Huilin; Zhang, Xin; Wang, Chao; Liu, Tao
Freeform surfaces have the advantage of balancing off-axis aberration. In this paper, based on the framework of nodal aberration theory (NAT) applied to the coaxial system, the third-order astigmatism and coma wave aberration expressions of an off-axis system with Zernike polynomial surfaces are derived. The relationship between the off-axis and surface shape acting on the nodal distributions is revealed. The nodal aberration properties of the off-axis freeform system are analyzed and validated by using full-field displays (FFDs). It has been demonstrated that adding Zernike terms, up to nine, to the off-axis system modifies the nodal locations, but the field dependence of the third-order aberration does not change. On this basis, an off-axis two-mirror freeform system with 500 mm effective focal length (EFL) and 300 mm entrance pupil diameter (EPD) working in long-wave infrared is designed. The field constant aberrations induced by surface tilting are corrected by selecting specific Zernike terms. The design results show that the nodes of third-order astigmatism and coma move back into the field of view (FOV). The modulation transfer function (MTF) curves are above 0.4 at 20 line pairs per millimeter (lp/mm) which meets the infrared reconnaissance requirement. This work provides essential insight and guidance for aberration correction in off-axis freeform system design.
An approach to model reactor core nodalization for deterministic safety analysis
Salim, Mohd Faiz Samsudin, Mohd Rafie; Mamat Ibrahim, Mohd Rizal; Roslan, Ridha Sadri, Abd Aziz; Farid, Mohd Fairus Abd
Adopting good nodalization strategy is essential to produce an accurate and high quality input model for Deterministic Safety Analysis (DSA) using System Thermal-Hydraulic (SYS-TH) computer code. The purpose of such analysis is to demonstrate the compliance against regulatory requirements and to verify the behavior of the reactor during normal and accident conditions as it was originally designed. Numerous studies in the past have been devoted to the development of the nodalization strategy for small research reactor (e.g. 250kW) up to the bigger research reactor (e.g. 30MW). As such, this paper aims to discuss the state-of-arts thermal hydraulics channel to be employed in the nodalization for RTP-TRIGA Research Reactor specifically for the reactor core. At present, the required thermal-hydraulic parameters for reactor core, such as core geometrical data (length, coolant flow area, hydraulic diameters, and axial power profile) and material properties (including the UZrH{sub 1.6}, stainless steel clad, graphite reflector) have been collected, analyzed and consolidated in the Reference Database of RTP using standardized methodology, mainly derived from the available technical documentations. Based on the available information in the database, assumptions made on the nodalization approach and calculations performed will be discussed and presented. The development and identification of the thermal hydraulics channel for the reactor core will be implemented during the SYS-TH calculation using RELAP5-3D{sup ®} computer code. This activity presented in this paper is part of the development of overall nodalization description for RTP-TRIGA Research Reactor under the IAEA Norwegian Extra-Budgetary Programme (NOKEBP) mentoring project on Expertise Development through the Analysis of Reactor Thermal-Hydraulics for Malaysia, denoted as EARTH-M.
ARPES Study of Nodal Quasiparticles Using Low-Energy Tunable Photons
NASA Astrophysics Data System (ADS)
Ino, Akihiro
Low-energy quasiparticle excitations govern the thermodynamic properties of a superconductor both in the zero-field and vortex-mixed states. For a d-wave superconductor, nodal quasiparticles are crucial excitations starting from zero energy. So far, however, the nodal quasiparticle dynamics of high-Tc cuprates has been controversial. For example, it has been reported by an angle-resolved-photoemission (ARPES) experiment that the marginal-Fermi-liquid behavior persists into the superconducting state without appreciable change in the scattering rate, while microwave conductivity increases upon the superconducting transition. Here, we show a new ARPES result that solves the controversies with unprecedented momentum-resolution. Low-energy tunable photons have enabled us to resolve a small nodal bilayer splitting clearly, and to reveal the detailed temperature- and energy-dependence of the scattering rate, indicating the behaviors unique to the nodal quasiparticles. Due to the opening of the d-wave gap, the nodal scattering rate is remarkably suppressed, and shows a linear energy dependence. The difference in the energy-linear term between the bilayer-resolved scattering rates hints the nature of impurities involved. This work was done in collaboration with T. Yamasaki, T. Kamo, K. Yamazaki, H. Anzai, M. Arita, H. Namatame, M. Taniguchi, Grad. Sch. of Science and Hiroshima Synchrotron Radiation Center, Hiroshima Univ., A. Fujimori, Dept. of Complexity Science and Engineering, Univ. of Tokyo, Z.-X. Shen, Dept. of Physics, Applied Physics and SSRL, Stanford Univ., M. Ishikado, K. Fujita, and S. Uchida, Dept. of Physics, Univ. of Tokyo.
A nodal triangle-based spectral element method for the shallow water equations on the sphere
NASA Astrophysics Data System (ADS)
Giraldo, F. X.; Warburton, T.
A nodal triangle-based spectral element (SE) method for the shallow water equations on the sphere is presented. The original SE method uses quadrilateral elements and high-order nodal Lagrange polynomials, constructed from a tensor-product of the Legendre-Gauss-Lobatto points. In this work, we construct the high-order Lagrange polynomials directly on the triangle using nodal sets obtained from the electrostatics principle [J.S. Hesthaven, From electrostatics to almost optimal nodal sets for polynomial interpolation in a simplex, SIAM Journal on Numerical Analysis 35 (1998) 655-676] and Fekete points [M.A. Taylor, B.A. Wingate, R.E. Vincent, An algorithm for computing Fekete points in the triangle, SIAM Journal on Numerical Analysis 38 (2000) 1707-1720]. These points have good approximation properties and far better Lebesgue constants than any other nodal set derived for the triangle. By employing triangular elements as the basic building-blocks of the SE method and the Cartesian coordinate form of the equations, we can use any grid imaginable including adaptive unstructured grids. Results for six test cases are presented to confirm the accuracy and stability of the method. The results show that the triangle-based SE method yields the expected exponential convergence and that it can be more accurate than the quadrilateral-based SE method even while using 30-60% fewer grid points especially when adaptive grids are used to align the grid with the flow direction. However, at the moment, the quadrilateral-based SE method is twice as fast as the triangle-based SE method because the latter does not yield a diagonal mass matrix.
An approach to model reactor core nodalization for deterministic safety analysis
NASA Astrophysics Data System (ADS)
Salim, Mohd Faiz; Samsudin, Mohd Rafie; Mamat @ Ibrahim, Mohd Rizal; Roslan, Ridha; Sadri, Abd Aziz; Farid, Mohd Fairus Abd
Adopting good nodalization strategy is essential to produce an accurate and high quality input model for Deterministic Safety Analysis (DSA) using System Thermal-Hydraulic (SYS-TH) computer code. The purpose of such analysis is to demonstrate the compliance against regulatory requirements and to verify the behavior of the reactor during normal and accident conditions as it was originally designed. Numerous studies in the past have been devoted to the development of the nodalization strategy for small research reactor (e.g. 250kW) up to the bigger research reactor (e.g. 30MW). As such, this paper aims to discuss the state-of-arts thermal hydraulics channel to be employed in the nodalization for RTP-TRIGA Research Reactor specifically for the reactor core. At present, the required thermal-hydraulic parameters for reactor core, such as core geometrical data (length, coolant flow area, hydraulic diameters, and axial power profile) and material properties (including the UZrH1.6, stainless steel clad, graphite reflector) have been collected, analyzed and consolidated in the Reference Database of RTP using standardized methodology, mainly derived from the available technical documentations. Based on the available information in the database, assumptions made on the nodalization approach and calculations performed will be discussed and presented. The development and identification of the thermal hydraulics channel for the reactor core will be implemented during the SYS-TH calculation using RELAP5-3D® computer code. This activity presented in this paper is part of the development of overall nodalization description for RTP-TRIGA Research Reactor under the IAEA Norwegian Extra-Budgetary Programme (NOKEBP) mentoring project on Expertise Development through the Analysis of Reactor Thermal-Hydraulics for Malaysia, denoted as EARTH-M.
Correlation effects and quantum oscillations in topological nodal-loop semimetals
NASA Astrophysics Data System (ADS)
Liu, Jianpeng; Balents, Leon
We study the unique physical properties of topological nodal-loop semimetals protected by the coexistence of time-reversal and inversion symmetries with negligible spin-orbit coupling. We argue that strong correlation effects occur at the surface of such systems for relatively small Hubbard interaction U , due to the narrow bandwidth of the "drumhead" surface states. In the Hartree-Fock approximation, at small U we obtain a surface ferromagnetic phase through a continuous quantum phase transition characterized by the surface-mode divergence of the spin susceptibility, while the bulk states remain very robust against local interactions and remain nonordered. At slightly increased interaction strength, the system quickly changes from a surface ferromagnetic phase to a surface charge-ordered phase through a first-order transition. When Rashba-type spin-orbit coupling is applied to the surface states, a canted ferromagnetic phase occurs at the surface for intermediate values of U . The quantum critical behavior of the surface ferromagnetic transition is nontrivial in the sense that the surface spin order parameter couples to Fermi-surface excitations from both surface and bulk states. This leads to unconventional Landau damping and consequently a naïve dynamical critical exponent z ≈1 when the Fermi level is close to the bulk nodal energy. We also show that, already without interactions, quantum oscillations arise due to bulk states, despite the absence of a Fermi surface when the chemical potential is tuned to the energy of the nodal loop. The bulk magnetic susceptibility diverges logarithmically whenever the nodal loop exactly overlaps with a quantized magnetic orbit in the bulk Brillouin zone. These correlation and transport phenomena are unique signatures of nodal-loop states.
Mammographic Density and Prediction of Nodal Status in Breast Cancer Patients
Hack, C. C.; Häberle, L.; Geisler, K.; Schulz-Wendtland, R.; Hartmann, A.; Fasching, P. A.; Uder, M.; Wachter, D. L.; Jud, S. M.; Loehberg, C. R.; Lux, M. P.; Rauh, C.; Beckmann, M. W.; Heusinger, K.
Aim: Nodal status remains one of the most important prognostic factors in breast cancer. The cellular and molecular reasons for the spread of tumor cells to the lymph nodes are not well understood and there are only few predictors in addition to tumor size and multifocality that give an insight into additional mechanisms of lymphatic spread. Aim of our study was therefore to investigate whether breast characteristics such as mammographic density (MD) add to the predictive value of the presence of lymph node metastases in patients with primary breast cancer. Methods: In this retrospective study we analyzed primary, metastasis-free breast cancer patients from one breast center for whom data on MD and staging information were available. A total of 1831 patients were included into this study. MD was assessed as percentage MD (PMD) using a semiautomated method and two readers for every patient. Multiple logistic regression analyses with nodal status as outcome were used to investigate the predictive value of PMD in addition to age, tumor size, Ki-67, estrogen receptor (ER), progesterone receptor (PR), grading, histology, and multi-focality. Results: Multifocality, tumor size, Ki-67 and grading were relevant predictors for nodal status. Adding PMD to a prediction model which included these factors did not significantly improve the prediction of nodal status (p = 0.24, likelihood ratio test). Conclusion: Nodal status could be predicted quite well with the factors multifocality, tumor size, Ki-67 and grading. PMD does not seem to play a role in the lymphatic spread of tumor cells. It could be concluded that the amount of extracellular matrix and stromal cell content of the breast which is reflected by MD does not influence the probability of malignant breast cells spreading from the primary tumor to the lymph nodes. PMID:24771910
Effects of out-of-plane disorder on the nodal quasiparticle and superconducting gap in single-layer Bi2Sr1.6L0.4CuO6+δ (L=La,Nd,Gd)
NASA Astrophysics Data System (ADS)
Hashimoto, M.; Yoshida, T.; Fujimori, A.; Lu, D. H.; Shen, Z.-X.; Kubota, M.; Ono, K.; Ishikado, M.; Fujita, K.; Uchida, S.
How out-of-plane disorder affects the electronic structure has been investigated for the single-layer cuprates Bi2Sr1.6L0.4CuO6+δ ( L=La , Nd, and Gd) by angle-resolved photoemission spectroscopy. We have observed that, with increasing disorder, while the Fermi-surface shape and band dispersions are not affected, the quasiparticle width increases, the antinodal gap is enhanced and the superconducting gap in the nodal region is depressed. The results indicate that the superconductivity is significantly depressed by out-of-plane disorder through the enhancement of the antinodal gap and the depression of the superconducting gap in the nodal region.
Cervical nodal necrosis is an independent survival predictor in nasopharyngeal carcinoma: an observational cohort study
Luo, Yangkun; Ren, Jing; Zhou, Peng; Gao, Yang; Yang, Guangquan; Lang, Jinyi
Purpose Most nasopharyngeal carcinoma (NPC) patients present with locoregionally advanced disease at the time of diagnosis; however, there is a lack of consensus on specific prognostic factors potentially improving overall survival, especially in late-stage disease. Herein, we conducted a retrospective study to evaluate various potential prognostic factors in order to provide useful information for clinical treatment of T3/T4-stage NPC. Patients and methods A total of 189 previously untreated NPC patients were enrolled in the current study. All patients received intensity-modulated radiotherapy. Survival, death, relapse-free survival (both local and regional), and metastasis were recorded during follow-up. Factors affecting patient survival were assessed by using univariate and multivariate analyses. Results The median follow-up time was 69 months. The 5-year local-regional recurrence-free survival, distant metastasis-free survival, progression-free survival (PFS), and overall survival (OS) of the entire group were 89.8%, 71.5%, 66.3%, and 68.9%, respectively. Univariate analysis revealed significant differences in the 5-year PFS (58.5% vs 72.5%, P=0.015) and OS (59.5% vs 75.8%, P=0.033) rates of patients with and without cervical nodal necrosis (CNN). Subgroup analyses revealed that CNN was associated with poorer distant metastasis-free survival and PFS among patients with N2 stage (P=0.046 and P=0.005) and with poorer PFS among patients with T3 or III stage (all P=0.022). Multivariate analysis revealed CNN to be an independent prognostic factor for PFS and OS (PFS: adjusted hazard ratio, 1.860; 95% CI: 1.134–3.051; P=0.014; OS: adjusted hazard ratio, 1.754; 95% CI: 1.061–2.899; P=0.028). Conclusion CNN is a potential independent negative prognostic factor in NPC patients. Our results suggest that stratification of NPC patients based on their CNN status should be considered as part of NPC disease management. PMID:27843328
Predicting regional neurodegeneration from the healthy brain functional connectome.
Zhou, Juan; Gennatas, Efstathios D; Kramer, Joel H; Miller, Bruce L; Seeley, William W
Neurodegenerative diseases target large-scale neural networks. Four competing mechanistic hypotheses have been proposed to explain network-based disease patterning: nodal stress, transneuronal spread, trophic failure, and shared vulnerability. Here, we used task-free fMRI to derive the healthy intrinsic connectivity patterns seeded by brain regions vulnerable to any of five distinct neurodegenerative diseases. These data enabled us to investigate how intrinsic connectivity in health predicts region-by-region vulnerability to disease. For each illness, specific regions emerged as critical network "epicenters" whose normal connectivity profiles most resembled the disease-associated atrophy pattern. Graph theoretical analyses in healthy subjects revealed that regions with higher total connectional flow and, more consistently, shorter functional paths to the epicenters, showed greater disease-related vulnerability. These findings best fit a transneuronal spread model of network-based vulnerability. Molecular pathological approaches may help clarify what makes each epicenter vulnerable to its targeting disease and how toxic protein species travel between networked brain structures.
The prognostic index: a useful pathologic guide for prediction of nodal metastases and survival in penile squamous cell carcinoma.
Chaux, Alcides; Caballero, Carmelo; Soares, Fernando; Guimarães, Gustavo C; Cunha, Isabel W; Reuter, Víctor; Barreto, José; Rodríguez, Ingrid; Cubilla, Antonio L
A concern of surgical oncologists has been to find a method to select patients for groin dissection in penile carcinomas considering the high morbidity of this procedure. A promising methodology, in the identification of early metastatic foci by the sentinel lymph node technique (initiated in Paraguay in the 1970s), was found, using a static anatomic approach, to be associated with a recurrence rate of 30%. Later, a dynamic method using radioactive tracers and peritumoral dye injection was introduced with an improvement in patients' outcome. Recurrences, however, remained high in most studies at a rate of about 15% to 20% except in few highly specialized centers with failure rates of 5%. The technical sophistication, lack of multicenter reproduction, and cost of dynamic sentinel node biopsies preclude their routine implementation in developing countries and other approaches are necessary. Because histologic grade, depth of tumor infiltration, and perineural invasion (PNI) are considered among the most important pathologic prognostic parameters in penile cancer, we devised a Prognostic Index combining these 3 factors. In this study, we are evaluating the incidence of nodal metastasis according to the Prognostic Index score. Pathologic materials from 193 patients with penectomy/circumcision and bilateral groin dissections for invasive squamous cell carcinoma were analyzed. The Prognostic Index (ranging from 2 to 7) consisted in the addition of numerical values given to histologic grade (1 to 3), deepest anatomic level involved by cancer (1 to 3), and presence of PNI (0 or 1). Histologic grades were defined as follows: grade 1, carcinomas with minimal to no atypias; grade 3, tumors showing any proportion of anaplastic cells; and grade 2, the remainder tumors. The anatomic levels and their numerical values were: in glans, lamina propria, 1; corpus spongiosum, 2; and corpus cavernosum, 3. In foreskin they were: lamina propria, 1; dartos, 2; and skin, 3. PNI was
Bifurcation behaviors of synchronized regions in logistic map networks with coupling delay
Tang, Longkun E-mail: email@example.com; Wu, Xiaoqun E-mail: email@example.com; Lu, Jun-an; Lü, Jinhu
Network synchronized regions play an extremely important role in network synchronization according to the master stability function framework. This paper focuses on network synchronous state stability via studying the effects of nodal dynamics, coupling delay, and coupling way on synchronized regions in Logistic map networks. Theoretical and numerical investigations show that (1) network synchronization is closely associated with its nodal dynamics. Particularly, the synchronized region bifurcation points through which the synchronized region switches from one type to another are in good agreement with those of the uncoupled node system, and chaotic nodal dynamics can greatly impede network synchronization. (2) The coupling delay generally impairs the synchronizability of Logistic map networks, which is also dominated by the parity of delay for some nodal parameters. (3) A simple nonlinear coupling facilitates network synchronization more than the linear one does. The results found in this paper will help to intensify our understanding for the synchronous state stability in discrete-time networks with coupling delay.
Nodal signaling is required for mesodermal and ventral but not for dorsal fates in the indirect developing hemichordate, Ptychodera flava
Röttinger, Eric; DuBuc, Timothy Q.; Amiel, Aldine R.; Martindale, Mark Q.
ABSTRACT Nodal signaling plays crucial roles in vertebrate developmental processes such as endoderm and mesoderm formation, and axial patterning events along the anteroposterior, dorsoventral and left-right axes. In echinoderms, Nodal plays an essential role in the establishment of the dorsoventral axis and left-right asymmetry, but not in endoderm or mesoderm induction. In protostomes, Nodal signaling appears to be involved only in establishing left-right asymmetry. Hence, it is hypothesized that Nodal signaling has been co-opted to pattern the dorsoventral axis of deuterostomes and for endoderm, mesoderm formation as well as anteroposterior patterning in chordates. Hemichordata, together with echinoderms, represent the sister taxon to chordates. In this study, we analyze the role of Nodal signaling in the indirect developing hemichordate Ptychodera flava. In particular, we show that during gastrulation nodal transcripts are detected in a ring of cells at the vegetal pole that gives rise to endomesoderm and in the ventral ectoderm at later stages of development. Inhibition of Nodal function disrupts dorsoventral fates and also blocks formation of the larval mesoderm. Interestingly, molecular analysis reveals that only mesodermal, apical and ventral gene expression is affected while the dorsal side appears to be patterned correctly. Taken together, this study suggests that the co-option of Nodal signaling in mesoderm formation and potentially in anteroposterior patterning has occurred prior to the emergence of chordates and that Nodal signaling on the ventral side is uncoupled from BMP signaling on the dorsal side, representing a major difference from the molecular mechanisms of dorsoventral patterning events in echinoderms. PMID:25979707
Nodal signaling is required for mesodermal and ventral but not for dorsal fates in the indirect developing hemichordate, Ptychodera flava.
Röttinger, Eric; DuBuc, Timothy Q; Amiel, Aldine R; Martindale, Mark Q
Nodal signaling plays crucial roles in vertebrate developmental processes such as endoderm and mesoderm formation, and axial patterning events along the anteroposterior, dorsoventral and left-right axes. In echinoderms, Nodal plays an essential role in the establishment of the dorsoventral axis and left-right asymmetry, but not in endoderm or mesoderm induction. In protostomes, Nodal signaling appears to be involved only in establishing left-right asymmetry. Hence, it is hypothesized that Nodal signaling has been co-opted to pattern the dorsoventral axis of deuterostomes and for endoderm, mesoderm formation as well as anteroposterior patterning in chordates. Hemichordata, together with echinoderms, represent the sister taxon to chordates. In this study, we analyze the role of Nodal signaling in the indirect developing hemichordate Ptychodera flava. In particular, we show that during gastrulation nodal transcripts are detected in a ring of cells at the vegetal pole that gives rise to endomesoderm and in the ventral ectoderm at later stages of development. Inhibition of Nodal function disrupts dorsoventral fates and also blocks formation of the larval mesoderm. Interestingly, molecular analysis reveals that only mesodermal, apical and ventral gene expression is affected while the dorsal side appears to be patterned correctly. Taken together, this study suggests that the co-option of Nodal signaling in mesoderm formation and potentially in anteroposterior patterning has occurred prior to the emergence of chordates and that Nodal signaling on the ventral side is uncoupled from BMP signaling on the dorsal side, representing a major difference from the molecular mechanisms of dorsoventral patterning events in echinoderms.
[Obvious or inapparent Wolff-Parkinson-White syndrome associated with duality of nodal conduction. Apropos of 4 cases].
Motté, G; Belhassen, B; Bodereau, P
In a series of 48 patients undergoing electrophysiological investigation for attacks of reciprocating tachycardia related to concealed or overt Wolff-Parkinson-White syndrome in sinus rhythm, 4 patients were found to have duality of nodal conduction. This association was responsible for several tachycardia circuits: in 2 patients the activation passed constantly retrogradely through the accessory pathway and then either through the slow nodal pathway or the rapid nodal pathway in the anterograde direction. In the other two patients, in addition to classical orthodromic tachycardia, purely intranodal reciprocating rhythms giving rise to sustained tachycardia in one case and to simple echos in the other, were observed.
Extended Field Intensity Modulated Radiation Therapy With Concomitant Boost for Lymph Node–Positive Cervical Cancer: Analysis of Regional Control and Recurrence Patterns in the Positron Emission Tomography/Computed Tomography Era
Vargo, John A.; Kim, Hayeon; Choi, Serah; Sukumvanich, Paniti; Olawaiye, Alexander B.; Kelley, Joseph L.; Edwards, Robert P.; Comerci, John T.; Beriwal, Sushil
Purpose: Positron emission tomography/computed tomography (PET/CT) is commonly used for nodal staging in locally advanced cervical cancer; however the false negative rate for para-aortic disease are 20% to 25% in PET-positive pelvic nodal disease. Unless surgically staged, pelvis-only treatment may undertreat para-aortic disease. We have treated patients with PET-positive nodes with extended field intensity modulated radiation therapy (IMRT) to address the para-aortic region prophylactically with concomitant boost to involved nodes. The purpose of this study was to assess regional control rates and recurrence patterns. Methods and Materials: Sixty-one patients with cervical cancer (stage IBI-IVA) diagnosed from 2003 to 2012 with PET-avid pelvic nodes treated with extended field IMRT (45 Gy in 25 fractions with concomitant boost to involved nodes to a median of 55 Gy in 25 fractions) with concurrent cisplatin and brachytherapy were retrospectively analyzed. The nodal location was pelvis-only in 41 patients (67%) and pelvis + para-aortic in 20 patients (33%). There were a total of 179 nodes, with a median number of positive nodes of 2 (range, 1-16 nodes) per patient and a median nodal size of 1.8 cm (range, 0.7-4.5 cm). Response was assessed by PET/CT at 12 to 16 weeks. Results: Complete clinical and imaging response at the first follow-up visit was seen in 77% of patients. At a mean follow-up time of 29 months (range, 3-116 months), 8 patients experienced recurrence. The sites of persistent/recurrent disease were as follows: cervix 10 (16.3%), regional nodes 3 (4.9%), and distant 14 (23%). The rate of para-aortic failure in patients with pelvic-only nodes was 2.5%. There were no significant differences in recurrence patterns by the number/location of nodes, largest node size, or maximum node standardized uptake value. The rate of late grade 3+ adverse events was 4%. Conclusions: Extended field IMRT was well tolerated and resulted in low regional recurrence
Nodal centrality of functional network in the differentiation of schizophrenia
Cheng, Hu; Newman, Sharlene; Goñi, Joaquín; Kent, Jerillyn S.; Howell, Josselyn; Bolbecker, Amanda; Puce, Aina; O'Donnell, Brian F.; Hetrick, William P.
A disturbance in the integration of information during mental processing has been implicated in schizophrenia, possibly due to faulty communication within and between brain regions. Graph theoretic measures allow quantification of functional brain networks. Functional networks are derived from correlations between time courses of brain regions. Group differences between SZ and control groups have been reported for functional network properties, but the potential of such measures to classify individual cases has been little explored. We tested whether the network measure of betweenness centrality could classify persons with schizophrenia and normal controls. Functional networks were constructed for 19 schizophrenic patients and 29 non-psychiatric controls based on resting state functional MRI scans. The betweenness centrality of each node, or fraction of shortest-paths that pass through it, was calculated in order to characterize the centrality of the different regions. The nodes with high betweenness centrality agreed well with hub nodes reported in previous studies of structural and functional networks. Using a linear support vector machine algorithm, the schizophrenia group was differentiated from non-psychiatric controls using the ten nodes with highest betweenness centrality. The classification accuracy was around 80%, and stable against connectivity thresholding. Better performance was achieved when using the ranks as feature space as opposed to the actual values of betweenness centrality. Overall, our findings suggest that changes in functional hubs are associated with schizophrenia, reflecting a variation of the underlying functional network and neuronal communications. In addition, a specific network property, betweenness centrality, can classify persons with SZ with a high level of accuracy. PMID:26299706
Nodal centrality of functional network in the differentiation of schizophrenia.
Cheng, Hu; Newman, Sharlene; Goñi, Joaquín; Kent, Jerillyn S; Howell, Josselyn; Bolbecker, Amanda; Puce, Aina; O'Donnell, Brian F; Hetrick, William P
A disturbance in the integration of information during mental processing has been implicated in schizophrenia, possibly due to faulty communication within and between brain regions. Graph theoretic measures allow quantification of functional brain networks. Functional networks are derived from correlations between time courses of brain regions. Group differences between SZ and control groups have been reported for functional network properties, but the potential of such measures to classify individual cases has been little explored. We tested whether the network measure of betweenness centrality could classify persons with schizophrenia and normal controls. Functional networks were constructed for 19 schizophrenic patients and 29 non-psychiatric controls based on resting state functional MRI scans. The betweenness centrality of each node, or fraction of shortest-paths that pass through it, was calculated in order to characterize the centrality of the different regions. The nodes with high betweenness centrality agreed well with hub nodes reported in previous studies of structural and functional networks. Using a linear support vector machine algorithm, the schizophrenia group was differentiated from non-psychiatric controls using the ten nodes with the highest betweenness centrality. The classification accuracy was around 80%, and stable against connectivity thresholding. Better performance was achieved when using the ranks as feature space as opposed to the actual values of betweenness centrality. Overall, our findings suggest that changes in functional hubs are associated with schizophrenia, reflecting a variation of the underlying functional network and neuronal communications. In addition, a specific network property, betweenness centrality, can classify persons with SZ with a high level of accuracy.
Vitality of Neural Networks under Reoccurring Catastrophic Failures
NASA Astrophysics Data System (ADS)
Sardi, Shira; Goldental, Amir; Amir, Hamutal; Vardi, Roni; Kanter, Ido
Catastrophic failures are complete and sudden collapses in the activity of large networks such as economics, electrical power grids and computer networks, which typically require a manual recovery process. Here we experimentally show that excitatory neural networks are governed by a non-Poissonian reoccurrence of catastrophic failures, where their repetition time follows a multimodal distribution characterized by a few tenths of a second and tens of seconds timescales. The mechanism underlying the termination and reappearance of network activity is quantitatively shown here to be associated with nodal time-dependent features, neuronal plasticity, where hyperactive nodes damage the response capability of their neighbors. It presents a complementary mechanism for the emergence of Poissonian catastrophic failures from damage conductivity. The effect that hyperactive nodes degenerate their neighbors represents a type of local competition which is a common feature in the dynamics of real-world complex networks, whereas their spontaneous recoveries represent a vitality which enhances reliable functionality.
Vitality of Neural Networks under Reoccurring Catastrophic Failures
Sardi, Shira; Goldental, Amir; Amir, Hamutal; Vardi, Roni; Kanter, Ido
Catastrophic failures are complete and sudden collapses in the activity of large networks such as economics, electrical power grids and computer networks, which typically require a manual recovery process. Here we experimentally show that excitatory neural networks are governed by a non-Poissonian reoccurrence of catastrophic failures, where their repetition time follows a multimodal distribution characterized by a few tenths of a second and tens of seconds timescales. The mechanism underlying the termination and reappearance of network activity is quantitatively shown here to be associated with nodal time-dependent features, neuronal plasticity, where hyperactive nodes damage the response capability of their neighbors. It presents a complementary mechanism for the emergence of Poissonian catastrophic failures from damage conductivity. The effect that hyperactive nodes degenerate their neighbors represents a type of local competition which is a common feature in the dynamics of real-world complex networks, whereas their spontaneous recoveries represent a vitality which enhances reliable functionality. PMID:27530974
Vitality of Neural Networks under Reoccurring Catastrophic Failures.
Sardi, Shira; Goldental, Amir; Amir, Hamutal; Vardi, Roni; Kanter, Ido
Catastrophic failures are complete and sudden collapses in the activity of large networks such as economics, electrical power grids and computer networks, which typically require a manual recovery process. Here we experimentally show that excitatory neural networks are governed by a non-Poissonian reoccurrence of catastrophic failures, where their repetition time follows a multimodal distribution characterized by a few tenths of a second and tens of seconds timescales. The mechanism underlying the termination and reappearance of network activity is quantitatively shown here to be associated with nodal time-dependent features, neuronal plasticity, where hyperactive nodes damage the response capability of their neighbors. It presents a complementary mechanism for the emergence of Poissonian catastrophic failures from damage conductivity. The effect that hyperactive nodes degenerate their neighbors represents a type of local competition which is a common feature in the dynamics of real-world complex networks, whereas their spontaneous recoveries represent a vitality which enhances reliable functionality.
The importance of earthquake-induced landslides to long-term slope erosion and slope-failure hazards in seismically active regions
Keefer, D.K.
This paper describes a general method for determining the amount of earthquake-induced landsliding that occurs in a seismically active region over time; this determination can be used as a quantitative measure of the long-term hazard from seismically triggered landslides as well as a measure of the importance of this process to regional slope-erosion rates and landscape evolution. The method uses data from historical earthquakes to relate total volume of landslide material dislodged by an earthquake to the magnitude, M, and seismic moment, M0, of the earthquake. From worldwide data, a linear-regression relation between landslide volume, V, and M0 is determined as: V = M0/1018.9(?? 0.13), where V is measured in m3 and M0 is in dyn-cm. To determine the amount of earthquake-generated landsliding over time, this relation is combined with data on seismic-moment release for a particular region, which may be derived from either earthquake-history or fault-slip data. The form of the M0-V relation allows the rate of production of earthquake-induced landslides over time to be determined from total rate of seismic-moment release without regard to the distribution of individual events, thus simplifying and generalizing the determination. Application of the method to twelve seismically active regions, with areas ranging from 13,275 to 2,308,000 km2, shows that erosion rates from earthquake-induced landslides vary significantly from region to region. Of the regions studied, the highest rates were determined for the island of Hawaii, New Zealand, western New Guinea, and the San Francisco Bay region of California. Significantly lower rates were determined for Iran, Tibet, the Sierra Nevada-Great Basin region of California, and central Japan (for the time period from 715 AD to the present). Intermediate rates were determined for Peru, southern California, onshore California, Turkey, and central Japan (for the time period from 1586 AD to the present). To determine the relative, long
Braunwald, Eugene
Despite major improvements in the treatment of virtually all cardiac disorders, heart failure (HF) is an exception, in that its prevalence is rising, and only small prolongations in survival are occurring. An increasing fraction, especially older women with diabetes, obesity, and atrial fibrillation exhibit HF with preserved systolic function. Several pathogenetic mechanisms appear to be operative in HF. These include increased hemodynamic overload, ischemia-related dysfunction, ventricular remodeling, excessive neurohumoral stimulation, abnormal myocyte calcium cycling, excessive or inadequate proliferation of the extracellular matrix, accelerated apoptosis, and genetic mutations. Biomarkers released as a consequence of myocardial stretch, imbalance between formation and breakdown of extracellular matrix, inflammation, and renal failure are useful in the identification of the pathogenetic mechanism and, when used in combination, may become helpful in estimating prognosis and selecting appropriate therapy. Promising new therapies that are now undergoing intensive investigation include an angiotensin receptor neprilysin inhibitor, a naturally-occurring vasodilator peptide, a myofilament sensitizer and several drugs that enhance Ca++ uptake by the sarcoplasmic reticulum. Cell therapy, using autologous bone marrow and cardiac progenitor cells, appears to be promising, as does gene therapy. Chronic left ventricular assistance with continuous flow pumps is being applied more frequently and successfully as destination therapy, as a bridge to transplantation, and even as a bridge to recovery and explantation. While many of these therapies will improve the care of patients with HF, significant reductions in prevalence will require vigorous, multifaceted, preventive approaches.
Self-energy of a nodal fermion in a d -wave superconductor
NASA Astrophysics Data System (ADS)
Chubukov, A. V.; Tsvelik, A. M.
We reconsider the self-energy of a nodal (Dirac) fermion in a two-dimensional d -wave superconductor. A conventional belief is that ImΣ(ω,T)˜max(ω3,T3) . We show that Σ(ω,k,T) for k along the nodal direction is actually a complex function of ω,T , and the deviation from the mass shell. In particular, the second-order self-energy diverges at a finite T when either ω or k-kF vanish. We show that the full summation of infinite diagrammatic series recovers a finite result for Σ , but the full angle-resolved photoemission spectroscopy spectral function is nonmonotonic and has a kink whose location compared to the mass shell differs qualitatively for spin-and charge-mediated interactions.
The effect of viscosity on steady transonic flow with a nodal solution topology
NASA Technical Reports Server (NTRS)
Owocki, Stanley P.; Zank, Gary P.
The effect of viscosity on a steady, transonic flow for which the inviscid limit has a nodal solution topology near the critical point is investigated. For the accelerating case, viscous solutions tend to repel each other, so that a very delicate choice of initial conditions is required to prevent them from diverging. Only the two critical solutions extend to arbitrarily large distances into both the subsonic and supersonic flows. For the decelerating case, the solutions tend to attract, and so an entire two-parameter family of solutions now extends over large distances. The general effect of viscosity on the solution degeneracy of a nodal topology is thus to reduce or limit it for the accelerating case and to enhance it for the decelerating case. The astrophysical implications of these findings are addressed.
The General-Use Nodal Network Solver (GUNNS) Modeling Package for Space Vehicle Flow System Simulation
NASA Technical Reports Server (NTRS)
Harvey, Jason; Moore, Michael
The General-Use Nodal Network Solver (GUNNS) is a modeling software package that combines nodal analysis and the hydraulic-electric analogy to simulate fluid, electrical, and thermal flow systems. GUNNS is developed by L-3 Communications under the TS21 (Training Systems for the 21st Century) project for NASA Johnson Space Center (JSC), primarily for use in space vehicle training simulators at JSC. It has sufficient compactness and fidelity to model the fluid, electrical, and thermal aspects of space vehicles in real-time simulations running on commodity workstations, for vehicle crew and flight controller training. It has a reusable and flexible component and system design, and a Graphical User Interface (GUI), providing capability for rapid GUI-based simulator development, ease of maintenance, and associated cost savings. GUNNS is optimized for NASA's Trick simulation environment, but can be run independently of Trick.
Anisotropic properties of unconventional superconductors in a magnetic field: testing the nodal stucture
NASA Astrophysics Data System (ADS)
Vorontsov, Anton; Vekhter, Ilya
We present a calculation of electronic specific heat and heat conductivity in a vortex state of quasi-two dimensional d-wave superconductors. We employ quasiclassical theory and use the Brand-Pesch-Tewordt approximation to model the superconducting state at moderate to high magnetic fields. Within this framework we investigate the dependence of heat capacity and heat conductivity on the angle of rotation of magnetic field with respect to the nodal directions. We find that the fourfold anisotropy due to nodal structure in both quantities changes sign in the temperature-field plane. This result helps resolve the apparent disagreement about the gap symmetry reached from the specific heat and the thermal conductivity measurements in CeCoIn5. We comment on the physics behind the difference between our results and those obtained in the Doppler shift approximation.
Comparing nodal versus bony metastatic spread using tumour phylogenies
Mangiola, Stefano; Hong, Matthew K. H.; Cmero, Marek; Kurganovs, Natalie; Ryan, Andrew; Costello, Anthony J.; Corcoran, Niall M.; Macintyre, Geoff; Hovens, Christopher M.
The role of lymph node metastases in distant prostate cancer dissemination and lethality is ill defined. Patients with metastases restricted to lymph nodes have a better prognosis than those with distant metastatic spread, suggesting the possibility of distinct aetiologies. To explore this, we traced patterns of cancer dissemination using tumour phylogenies inferred from genome-wide copy-number profiling of 48 samples across 3 patients with lymph node metastatic disease and 3 patients with osseous metastatic disease. Our results show that metastatic cells in regional lymph nodes originate from evolutionary advanced extraprostatic tumour cells rather than less advanced central tumour cell populations. In contrast, osseous metastases do not exhibit such a constrained developmental lineage, arising from either intra or extraprostatic tumour cell populations, at early and late stages in the evolution of the primary. Collectively, this comparison suggests that lymph node metastases may not be an intermediate developmental step for distant osseous metastases, but rather represent a distinct metastatic lineage. PMID:27653089
Unidimensional Measurement May Evaluate Target Lymph Nodal Response After Induction Chemotherapy for Nasopharyngeal Carcinoma
Chen, Chuanben; Zhang, Mingwei; Xu, Yuanji; Yue, Qiuyuan; Bai, Penggang; Zhou, Lin; Xiao, Youping; Zheng, Dechun; Lin, Kongqi; Qiu, Sufang; Chen, Yunbin; Pan, Jianji
Abstract The aim of the study was to evaluate whether short axis and long axis on axial and coronal magnetic resonance imaging planes would reflect the tumor burden or alteration in size after induction chemotherapy in nasopharyngeal carcinoma. Patients with pathologically confirmed nasopharyngeal carcinoma (n = 37) with at least 1 positive cervical lymph node (axial short axis ≥15 mm) were consecutively enrolled in this prospective study. Lymph nodal measurements were performed along its short axis and long axis in both axial and coronal magnetic resonance imaging planes at diagnosis and after 2 cycles of induction chemotherapy. In addition, lymph nodal volumes were automatically calculated in 3D treatment-planning system, which were used as reference standard. Student's t test or nonparametric Mann–Whitney U test was used to compare the continuous quantitative variables. Meanwhile, the κ statistic and McNemar's test were used to evaluate the degree of agreement and discordance in response categorization among different measurements. Axial short axis was significantly associated with volumes at diagnosis (P < 0.001). A good agreement (κ=0.583) was found between axial short axis and volumetric criteria. However, the inconsistent lymph nodal shrinkage in 4 directions was observed. Axial short-axis shrinking was more rapid than the other 3 parameters. Interestingly, when utilizing the alternative planes for unidimensional measurements to assess tumor response, coronal short-axis showed the best concordance (κ=0.792) to the volumes. Axial short axis may effectively reflect tumor burden or change in tumor size in the assessment of target lymph nodal response after induction chemotherapy for nasopharyngeal carcinoma. However, it should be noted that axial short axis may amplify the therapeutic response. In addition, the role of coronal short axis in the assessment of tumor response needs further evaluation. PMID:26945354
Nodal recovery, dual pathway physiology, and concealed conduction determine complex AV dynamics in human atrial tachyarrhythmias.
Masè, Michela; Glass, Leon; Disertori, Marcello; Ravelli, Flavia
The genesis of complex ventricular rhythms during atrial tachyarrhythmias in humans is not fully understood. To clarify the dynamics of atrioventricular (AV) conduction in response to a regular high-rate atrial activation, 29 episodes of spontaneous or pacing-induced atrial flutter (AFL), covering a wide range of atrial rates (cycle lengths from 145 to 270 ms), were analyzed in 10 patients. AV patterns were identified by applying firing sequence and surrogate data analysis to atrial and ventricular activation series, whereas modular simulation with a difference-equation AV node model was used to correlate the patterns with specific nodal properties. AV node response at high atrial rate was characterized by 1) AV patterns of decreasing conduction ratios at the shortening of atrial cycle length (from 236.3 ± 32.4 to 172.6 ± 17.8 ms) according to a Farey sequence ordering (conduction ratio from 0.34 ± 0.12 to 0.23 ± 0.06; P < 0.01); 2) the appearance of high-order alternating Wenckebach rhythms, such as 6:2, 10:2, and 12:2, associated with ventricular interval oscillations of large amplitude (407.7 ± 150.4 ms); and 3) the deterioration of pattern stability at advanced levels of block, with the percentage of stable patterns decreasing from 64.3 ± 35.2% to 28.3 ± 34.5% (P < 0.01). Simulations suggested these patterns to originate from the combined effect of nodal recovery, dual pathway physiology, and concealed conduction. These results indicate that intrinsic nodal properties may account for the wide spectrum of AV block patterns occurring during regular atrial tachyarrhythmias. The characterization of AV nodal function during different AFL forms constitutes an intermediate step toward the understanding of complex ventricular rhythms during atrial fibrillation.
Numerical divergence effects of equivalence theory in the nodal expansion method
Zika, M.R.; Downar, T.J. )
Accurate solutions of the advanced nodal equations require the use of discontinuity factors (DFs) to account for the homogenization errors that are inherent in all coarse-mesh nodal methods. During the last several years, nodal equivalence theory (NET) has successfully been implemented for the Cartesian geometry and has received widespread acceptance in the light water reactor industry. The extension of NET to other reactor types has had limited success. Recent efforts to implement NET within the framework of the nodal expansion method have successfully been applied to the fast breeder reactor. However, attempts to apply the same methods to thermal reactors such as the Modular High-Temperature Gas Reactor (MHTGR) have led to numerical divergence problems that can be attributed directly to the magnitude of the DFs. In the work performed here, it was found that the numerical problems occur in the inner and upscatter iterations of the solution algorithm. These iterations use a Gauss-Seidel iterative technique that is always convergent for problems with unity DFs. However, for an MHTGR model that requires large DFs, both the inner and upscatter iterations were divergent. Initial investigations into methods for bounding the DFs have proven unsatisfactory as a means of remedying the convergence problems. Although the DFs could be bounded to yield a convergent solution, several cases were encountered where the resulting flux solution was less accurate than the solution without DFs. For the specific case of problems without upscattering, an alternate numerical method for the inner iteration, an LU decomposition, was identified and shown to be feasible.
Gastroblastoma in a 28-year-old man with nodal metastasis: proof of the malignant potential.
Wey, Elizabeth A; Britton, Andrew J; Sferra, Joseph J; Kasunic, Tim; Pepe, Linda R; Appelman, Henry D
Gastroblastoma is a newly defined neoplasm of children and young adults with only 4 reported cases to date. Morphologically, the tumor is a mixture of epithelial structures and stromal elements with minimal cytologic atypia. In these 4 reported cases, there were no metastases or postresection recurrences. We report a case of gastroblastoma in a 28-year-old man with a histologic nodal metastasis and clinical distant metastases.
Nodal collocation approximation for the multidimensional PL equations applied to transport source problems
Verdu, G.; Capilla, M.; Talavera, C. F.; Ginestar, D.
PL equations are classical high order approximations to the transport equations which are based on the expansion of the angular dependence of the angular neutron flux and the nuclear cross sections in terms of spherical harmonics. A nodal collocation method is used to discretize the PL equations associated with a neutron source transport problem. The performance of the method is tested solving two 1D problems with analytical solution for the transport equation and a classical 2D problem. (authors)
NODAL in the uterus is necessary for proper placental development and maintenance of pregnancy.
Park, Craig B; DeMayo, Francesco J; Lydon, John P; Dufort, Daniel
Preterm birth is the single leading cause of perinatal mortality in developed countries, affecting approximately 12% of pregnancies and accounting for 75% of neonatal loss in the United States. Despite the prevalence and severity of premature delivery, the causes and mechanisms that underlie spontaneous and idiopathic preterm birth remain unknown. Our inability to elucidate these fundamental causes has been attributed to a poor understanding of the signaling pathways associated with the premature induction of parturition and a lack of suitable animal models available for preterm birth research. In this study, we describe the generation and analysis of a novel conditional knockout of the transforming growth factor beta (TGFB) superfamily member, Nodal, from the maternal reproductive tract of mice. Strikingly, uterine Nodal knockout females exhibited a severe malformation of the maternal decidua basalis during placentation, leading to significant intrauterine growth restriction, and ultimately preterm birth and fetal loss on Day 17.5 of gestation. Using several approaches, we characterized aberrant placental development and demonstrated that reduced proliferation combined with increased apoptosis resulted in a diminished decidua basalis and compromised maternal-fetal interface. Last, we evaluated various components of the established parturition cascade and determined that preterm birth derived from the maternal Nodal knockout occurs prior to PTGS2 (COX-2) upregulation at the placental interface. Taken together, the results presented in this study highlight an in vivo role for maternal NODAL during placentation, present an interesting link between disrupted decidua basalis formation and premature parturition, and describe a potentially valuable model toward elucidating the complex processes that underlie preterm birth.
Nodal soliton solutions for generalized quasilinear Schrödinger equations
Deng, Yinbin Peng, Shuangjie; Wang, Jixiu
This paper is concerned with constructing nodal radial solutions for generalized quasilinear Schrödinger equations in R{sup N} which arise from plasma physics, fluid mechanics, as well as high-power ultashort laser in matter. For any given integer k ⩾ 0, by using a change of variables and minimization argument, we obtain a sign-changing minimizer with k nodes of a minimization problem.
Atrioventricular Nodal Re-entry Tachycardia in Identical Twins: A Case Report and Literature Review
Barake, Walid; Caldwell, Jane; Baranchuk, Adrian
This report details the case of 17 year old identical twins who both presented with paroxysmal supraventricular tachycardia (PSVT). Electrophysiological studies revealed atrioventricular nodal reentry tachycardia (AVNRT) in both twins. Successful but technically challenging slow pathway ablation was performed in both twins. This is the first reported case of confirmed AVNRT in identical twins which adds strong evidence to heritability of the dual AV node physiology and AVNRT. A review of the current literature regarding PSVT in monozygotic twins is provided. PMID:23329875
Ionic mechanisms involved in the nodal swelling of myelinated axons caused by marine toxins.
Benoit, Evelyne; Mattei, Cesar; Ouanounou, Gilles; Meunier, Frederic A; Suput, Dusan; Le Gall, Frederic; Marquais, Michel; Dechraoui, Marie Y; Molgo, Jordi
This review describes the ionic mechanisms involved in the nodal swelling of frog myelinated axons caused by specific marine neurotoxins (ciguatoxins, brevetoxins, Conus consors toxin and equinatoxin-II), analysed using confocal laser scanning microscopy. We have focussed on toxins that either target neuronal voltage-dependent Na+ channels, or that form cation-selective pores and indirectly affect the functioning of the Na(+)-Ca(++)exchanger.
Seismicity, shear failure and modes of deformation in deep subduction zones
NASA Technical Reports Server (NTRS)
Lundgren, Paul R.; Giardini, Domenico
The joint hypocentral determination method is used to relocate deep seismicity reported in the International Seismological Center catalog for earthquakes deeper than 400 km in the Honshu, Bonin, Mariannas, Java, Banda, and South America subduction zones. Each deep seismic zone is found to display planar features of seismicity parallel to the Harvard centroid-moment tensor nodal planes, which are identified as planes of shear failure. The sense of displacement on these planes is one of resistance to deeper penetration.
Notch activity induces Nodal expression and mediates the establishment of left–right asymmetry in vertebrate embryos
Raya, Ángel; Kawakami, Yasuhiko; Rodríguez-Esteban, Concepción; Büscher, Dirk; Koth, Christopher M.; Itoh, Tohru; Morita, Masanobu; Raya, R. Marina; Dubova, Ilir; Bessa, Joaquín Grego; de la Pompa, José Luis; Belmonte, Juan Carlos Izpisúa
Left-sided expression of Nodal in the lateral plate mesoderm is a conserved feature necessary for the establishment of normal left–right asymmetry during vertebrate embryogenesis. By using gain- and loss-of-function experiments in zebrafish and mouse, we show that the activity of the Notch pathway is necessary and sufficient for Nodal expression around the node, and for proper left–right determination. We identify Notch-responsive elements in the Nodal promoter, and unveil a direct relationship between Notch activity and Nodal expression around the node. Our findings provide evidence for a mechanism involving Notch activity that translates an initial symmetry-breaking event into asymmetric gene expression. PMID:12730123
A coarse-mesh nodal method-diffusive-mesh finite difference method
Joo, H.; Nichols, W.R.
Modern nodal methods have been successfully used for conventional light water reactor core analyses where the homogenized, node average cross sections (XSs) and the flux discontinuity factors (DFs) based on equivalence theory can reliably predict core behavior. For other types of cores and other geometries characterized by tightly-coupled, heterogeneous core configurations, the intranodal flux shapes obtained from a homogenized nodal problem may not accurately portray steep flux gradients near fuel assembly interfaces or various reactivity control elements. This may require extreme values of DFs (either very large, very small, or even negative) to achieve a desired solution accuracy. Extreme values of DFs, however, can disrupt the convergence of the iterative methods used to solve for the node average fluxes, and can lead to a difficulty in interpolating adjacent DF values. Several attempts to remedy the problem have been made, but nothing has been satisfactory. A new coarse-mesh nodal scheme called the Diffusive-Mesh Finite Difference (DMFD) technique, as contrasted with the coarse-mesh finite difference (CMFD) technique, has been developed to resolve this problem. This new technique and the development of a few-group, multidimensional kinetics computer program are described in this paper.
Nodal gap detection through polar angle-resolved density of states measurements in uniaxial superconductors
NASA Astrophysics Data System (ADS)
Tsutsumi, Yasumasa; Nomoto, Takuya; Ikeda, Hiroaki; Machida, Kazushige
We propose a spectroscopic method to identify the nodal gap structure in unconventional superconductors. This method is best suited for locating the horizontal line node and for pinpointing the isolated point nodes by measuring polar angle (θ ) resolved zero-energy density of states N (θ ) . This is measured by specific heat or thermal conductivity at low temperatures under a magnetic field. We examine a variety of uniaxially symmetric nodal structures, including point and/or line nodes with linear and quadratic dispersions, by solving the Eilenberger equation in vortex states. It is found that (a) the maxima of N (θ ) continuously shift from the antinodal to the nodal direction (θn) as a field increases accompanying the oscillation pattern reversal at low and high fields. Furthermore, (b) local minima emerge next to θn on both sides, except for the case of the linear point node. These features are robust and detectable experimentally. Experimental results of N (θ ) performed on several superconductors, UPd2Al3,URu2Si2,CuxBi2Se3 , and UPt3, are examined and commented on in light of the present theory.
Measurement of the Nodal Precession of WASP-33 b via Doppler Tomography
NASA Astrophysics Data System (ADS)
Johnson, Marshall C.; Cochran, William D.; Collier Cameron, Andrew; Bayliss, Daniel
We have analyzed new and archival time series spectra taken six years apart during transits of the hot Jupiter WASP-33 b, and spectroscopically resolved the line profile perturbation caused by the Rossiter-McLaughlin effect. The motion of this line profile perturbation is determined by the path of the planet across the stellar disk, which we show to have changed between the two epochs due to nodal precession of the planetary orbit. We measured rates of change of the impact parameter and the sky-projected spin-orbit misalignment of {db}/{dt}={-0.0228}-0.0018+0.0050 {{yr}}-1 and dλ /{dt}={-0\\buildrel{\\circ}\\over{.} 487}-0.076+0.089 {{yr}}-1, respectively, corresponding to a rate of nodal precession of d{{Ω }}/{dt}=0\\buildrel{\\circ}\\over{.} {373}-0.083+0.031 {{yr}}-1. This is only the second measurement of nodal precession for a confirmed exoplanet transiting a single star. Finally, we used the rate of precession to set limits on the stellar gravitational quadrupole moment of 0.0054≤slant {J}2≤slant 0.035.
Anisotropic density fluctuations, plasmons, and Friedel oscillations in nodal line semimetal
NASA Astrophysics Data System (ADS)
Rhim, Jun-Won; Kim, Yong Baek
Motivated by recent experimental efforts on three-dimensional semimetals, we investigate the static and dynamic density response of the nodal line semimetal by computing the polarizability for both undoped and doped cases. The nodal line semimetal in the absence of doping is characterized by a ring-shape zero energy contour in momentum space, which may be considered as a collection of Dirac points. In the doped case, the Fermi surface has a torus shape and two independent processes of the momentum transfer contribute to the singular features of the polarizability even though we only have a single Fermi surface. In the static limit, there exist two independent singularities in the second derivative of the static polarizability. This results in the highly anisotropic Friedel oscillations which show the angle-dependent algebraic power law and the beat phenomena in the oscillatory electron density near a charged impurity. Furthermore, the dynamical polarizability has two singular lines along {\\hslash }ω =γ p and {\\hslash }ω =γ p{sin}η , where η is the angle between the external momentum {p} and the plane where the nodal ring lies. From the dynamical polarizability, we obtain the plasmon modes in the doped case, which show anisotropic dispersions and angle-dependent plasma frequencies. Qualitative differences between the low and high doping regimes are discussed in light of future experiments.
Disappearance of nodal gap across the insulator-superconductor transition in a copper-oxide superconductor.
Peng, Yingying; Meng, Jianqiao; Mou, Daixiang; He, Junfeng; Zhao, Lin; Wu, Yue; Liu, Guodong; Dong, Xiaoli; He, Shaolong; Zhang, Jun; Wang, Xiaoyang; Peng, Qinjun; Wang, Zhimin; Zhang, Shenjin; Yang, Feng; Chen, Chuangtian; Xu, Zuyan; Lee, T K; Zhou, X J
The parent compound of the copper-oxide high-temperature superconductors is a Mott insulator. Superconductivity is realized by doping an appropriate amount of charge carriers. How a Mott insulator transforms into a superconductor is crucial in understanding the unusual physical properties of high-temperature superconductors and the superconductivity mechanism. Here we report high-resolution angle-resolved photoemission measurement on heavily underdoped Bi₂Sr₂-xLaxCuO(₆+δ) system. The electronic structure of the lightly doped samples exhibit a number of characteristics: existence of an energy gap along the nodal direction, d-wave-like anisotropic energy gap along the underlying Fermi surface, and coexistence of a coherence peak and a broad hump in the photoemission spectra. Our results reveal a clear insulator-superconductor transition at a critical doping level of ~0.10 where the nodal energy gap approaches zero, the three-dimensional antiferromagnetic order disappears, and superconductivity starts to emerge. These observations clearly signal a close connection between the nodal gap, antiferromagnetism and superconductivity.
Formin DAAM1 Organizes Actin Filaments in the Cytoplasmic Nodal Actin Network
Luo, Weiwei; Lieu, Zi Zhao; Manser, Ed; Bershadsky, Alexander D.; Sheetz, Michael P.
A nodal cytoplasmic actin network underlies actin cytoplasm cohesion in the absence of stress fibers. We previously described such a network that forms upon Latrunculin A (LatA) treatment, in which formin DAAM1 was localized at these nodes. Knock down of DAAM1 reduced the mobility of actin nodes but the nodes remained. Here we have investigated DAAM1 containing nodes after LatA washout. DAAM1 was found to be distributed between the cytoplasm and the plasma membrane. The membrane binding likely occurs through an interaction with lipid rafts, but is not required for F-actin assembly. Interesting the forced interaction of DAAM1 with plasma membrane through a rapamycin-dependent linkage, enhanced F-actin assembly at the cell membrane (compared to the cytoplasm) after the LatA washout. However, immediately after addition of both rapamycin and LatA, the cytoplasmic actin nodes formed transiently, before DAAM1 moved to the membrane. This was consistent with the idea that DAAM1 was initially anchored to cytoplasmic actin nodes. Further, photoactivatable tracking of DAAM1 showed DAAM1 was immobilized at these actin nodes. Thus, we suggest that DAAM1 organizes actin filaments into a nodal complex, and such nodal complexes seed actin network recovery after actin depolymerization. PMID:27760153
Extending nodal aberration theory to include mount-induced aberrations with application to freeform surfaces.
Fuerschbach, Kyle; Rolland, Jannick P; Thompson, Kevin P
This paper introduces the path forward for the integration of freeform optical surfaces, particularly those related to φ-polynomial surfaces, including Zernike polynomial surfaces, with nodal aberration theory. With this formalism, the performance of an optical system throughout the field of view can be anticipated analytically accounting for figure error, mount-induced errors, and misalignment. Previously, only misalignments had been described by nodal aberration theory, with the exception of one special case for figure error. As an example of these new results, three point mounting error that results in a Zernike trefoil deformation is studied for the secondary mirror of a two mirror and three mirror telescope. It is demonstrated that for the case of trefoil deformation applied to a surface not at the stop, there is the anticipated field constant contribution to elliptical coma (also called trefoil) as well as a newly identified field dependent contribution to astigmatism: field linear, field conjugate astigmatism. The magnitude of this astigmatic contribution varies linearly with the field of view; however, it has a unique variation in orientation with field that is described mathematically by a concept that is unique to nodal aberration theory known as the field conjugate vector.
Closed-chest ablation of retrograde conduction in patients with atrioventricular nodal reentrant tachycardia.
Haissaguerre, M; Warin, J F; Lemetayer, P; Saoudi, N; Guillem, J P; Blanchot, P
We applied a new technique of catheter ablation to treat atrioventricular nodal reentrant tachycardia and preserve anterograde conduction, performing this procedure in 21 patients with repetitive episodes of tachycardia refractory to antiarrhythmic drugs. Using atrial activation in the His-bundle lead as a reference, we selected the optimal site of ablation by positioning an electrode catheter so that atrial activation occurred simultaneously with or earlier than the reference activation during tachycardia. At this site, the His-bundle deflection was completely absent or was present only at a low amplitude (less than 0.1 mV). In the majority of patients, these criteria could be met by withdrawing the catheter 5 to 10 mm from the site of the His-bundle recording (adjacent to the reference catheter). Shocks of 160 or 240 J were delivered at this site (cumulative energy [mean +/- SD], 689 +/- 442 J). Treatment resulted in preferential abolition or impairment of retrograde nodal conduction. Anterograde conduction, although modified, was preserved in 19 patients; complete heart block persisted in 2 patients. Sixteen patients remained free of arrhythmia, without medication or implantation of a pacemaker, for a mean follow-up period of 14 +/- 8 months (range, 7 to 42). Tachycardia was not inducible in 14 patients in a follow-up electrophysiologic study performed 3.6 +/- 6 months after the procedure. We conclude that catheter ablation is an effective alternative for the treatment of atrioventricular nodal tachycardia in patients with drug-resistant tachycardia.
Nonfluoroscopic Imaging as Guidance for Radiofrequency Ablation of Atrioventricular Nodal Reentrant Tachycardia after Mustard Repair
Nguyen, Dinh Q.; Sobczak, Henrik; Brandts, Bodo
Most tachycardias in the pulmonary venous atrium are inaccessible by direct means and require either a retrograde approach or a transseptal approach for ablation. We present a case in which successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia was accomplished via a retrograde transaortic approach guided by nonfluoroscopic mapping with use of the NavX™ mapping system. The patient was a 49-year-old woman who at the age of 4 years had undergone Mustard repair for complete dextrotransposition of the great arteries. Three-dimensional reconstructions of the ascending aorta, right ventricle, systemic venous atrium, left ventricle, and superior vena cava–inferior vena cava baffle complex were created, and the left-sided His bundle was marked. After a failed attempt at ablation from the systemic venous side, we eliminated the atrioventricular nodal reentrant tachycardia by ablation from the pulmonary venous side. This case is, to our knowledge, the first report of successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia after Mustard repair for this congenital cardiac malformation in which ablation was guided by 3-dimensional nonfluoroscopic imaging. This imaging technique enabled accurate anatomic location of the ablation catheters in relation to the His bundle marked from the systemic venous side. PMID:28265215
Reticulin and NM23 staining in the interpretation of lymph nodal nevus rests.
Kanner, William A; Barry, Catherine I; Smart, Chandra N; Frishberg, David P; Binder, Scott W; Wick, Mark R
Melanocytic nevus rests in lymph nodes are a known diagnostic challenge, especially in patients with a history of melanoma. Reticulin and NM23 have been studied in this context. The pattern of reticulin staining in melanomas surrounds groups/nests of melanocytes but individual cells in benign nevi. NM23, a metastasis-suppressor gene, has an association with metastatic potential in melanomas and some carcinomas. Twenty-eight cases (14 cases of metastatic melanoma to lymph nodes and 14 cases of lymph node nevus rests, all confirmed with Melan-A staining) were stained with reticulin and NM23. The pattern of reticulin staining was reported as surrounding groups if staining was noted in approximately 5-10 melanocytes in greater than 50% of the lesion but was otherwise reported as surrounding individual melanocytes. Cytoplasmic staining was considered to represent reactivity for NM23. Reticulin staining around groups of melanocytes was identified in all 14 cases of metastatic melanoma. Regarding nodal nevus rest cases, 12 of 14 cases (86%) demonstrated staining around individual melanocytes, whereas in 2 cases, reticulin surrounded melanocytic groups. NM23 staining was equivocal in all cases. Reticulin staining reliably invests groups of melanocytes in cases of metastatic melanoma, whereas in nodal nevus rests, it predominantly surrounds individual melanocytes. NM23 demonstrated no discriminatory value in this analysis. In cases in which a collection of melanocytes is present within a lymph node, reticulin deposition around individual melanocytes supports a diagnosis of lymph nodal nevus rest.
Large-N Nodal Seismic Deployment at Mount St Helens
NASA Astrophysics Data System (ADS)
Hansen, S. M.; Schmandt, B.; Vidale, J. E.; Creager, K. C.; Levander, A.; Kiser, E.; Barklage, M.; Hollis, D.
In late July of 2014 over 900 autonomous short period seismometers were deployed within 12 km of the summit crater at Mount St Helens. In concert with the larger iMUSH experiment, these data constitute the largest seismic interrogation of an active volcano ever conducted. The array was deployed along the road and trail system of the national volcanic monument and adjacent regions with an average station spacing of 250 meters and included several station clusters with increased sampling density. The 10 Hz phones recorded the vertical component wavefield continuously at 250 Hz sampling rate over a period of approximately two weeks. During the recording time, the Pacific Northwest Seismic Network detected ~65 earthquakes within the array footprint ranging in magnitude from -0.9 to 1.1, the majority of which were located beneath the crater at less than 10 km depth. In addition to the natural seismicity, 23 explosion sources from the iMUSH active source experiment were recorded, several of which exceeded magnitude 2. Preliminary results for this project will include an expanded event catalog as the array should significantly reduce the detection threshold. The sheer number of instruments allows for stacking of station clusters producing high signal-to-noise beam traces which can be used for event triggering and for creating waveform templates to measure relative travel-times across the array via cross-correlation. The ability of the array to estimate focal mechanisms from event radiation patterns and delineate complex path effects will also be investigated. The density and azimuthal coverage provide by this array offers an excellent opportunity to investigate short-wavelength variations of the seismic wavefield in a complex geologic environment. Previous seismic tomography results suggest the presence of a shallow magma chamber at 1-3 km depth near the region of shallow seismicity as evidenced by a P wave low-velocity anomaly of at least -5.5% [Waite and Moran, 2009
Transport Corrections in Nodal Diffusion Codes for HTR Modeling
Abderrafi M. Ougouag; Frederick N. Gleicher
The cores and reflectors of High Temperature Reactors (HTRs) of the Next Generation Nuclear Plant (NGNP) type are dominantly diffusive media from the point of view of behavior of the neutrons and their migration between the various structures of the reactor. This means that neutron diffusion theory is sufficient for modeling most features of such reactors and transport theory may not be needed for most applications. Of course, the above statement assumes the availability of homogenized diffusion theory data. The statement is true for most situations but not all. Two features of NGNP-type HTRs require that the diffusion theory-based solution be corrected for local transport effects. These two cases are the treatment of burnable poisons (BP) in the case of the prismatic block reactors and, for both pebble bed reactor (PBR) and prismatic block reactor (PMR) designs, that of control rods (CR) embedded in non-multiplying regions near the interface between fueled zones and said non-multiplying zones. The need for transport correction arises because diffusion theory-based solutions appear not to provide sufficient fidelity in these situations.
SU-E-J-179: Prediction of Pelvic Nodal Coverage Using Mutual Information Between Cone-Beam and Planning CTs
Jani, S; Kishan, A; O'Connell, D; King, C; Steinberg, M; Low, D; Lamb, J
Purpose: To investigate if pelvic nodal coverage for prostate patients undergoing intensity modulated radiotherapy (IMRT) can be predicted using mutual image information computed between planning and cone-beam CTs (CBCTs). Methods: Four patients with high-risk prostate adenocarcinoma were treated with IMRT on a Varian TrueBeam. Plans were designed such that 95% of the nodal planning target volume (PTV) received the prescription dose of 45 Gy (N=1) or 50.4 Gy (N=3). Weekly CBCTs (N=25) were acquired and the nodal clinical target volumes and organs at risk were contoured by a physician. The percent nodal volume receiving prescription dose was recorded as a ground truth. Using the recorded shifts performed by the radiation therapists at the time of image acquisition, CBCTs were aligned with the planning kVCT. Mutual image information (MI) was calculated between the CBCT and the aligned planning CT within the contour of the nodal PTV. Due to variable CBCT fields-of-view, CBCT images covering less than 90% of the nodal volume were excluded from the analysis, resulting in the removal of eight CBCTs. Results: A correlation coefficient of 0.40 was observed between the MI metric and the percent of the nodal target volume receiving the prescription dose. One patient's CBCTs had clear outliers from the rest of the patients. Upon further investigation, we discovered image artifacts that were present only in that patient's images. When those four images were excluded, the correlation improved to 0.81. Conclusion: This pilot study shows the potential of predicting pelvic nodal dosimetry by computing the mutual image information between planning CTs and patient setup CBCTs. Importantly, this technique does not involve manual or automatic contouring of the CBCT images. Additional patients and more robust exclusion criteria will help validate our findings.
Bidecadal variability in the intermediate waters of the northwestern subarctic Pacific and the Okhotsk Sea in relation to 18.6-year period nodal tidal cycle
NASA Astrophysics Data System (ADS)
Osafune, S.; Yasuda, I.
On the basis of historical oceanographic data, we investigated the long-term variations of the intermediate waters in the four regions in the northwestern subarctic Pacific: Oyashio, Okhotsk Sea Mode Water, Upstream Oyashio and East Kamchatka Current. We found bidecadal oscillations in these water properties that are synchronized with the 18.6-year period nodal cycle. In periods when the diurnal tide is strong, the following characteristics are found: Apparent oxygen utilization and phosphate are low in Oyashio and Okhotsk Sea Mode Water. The thickness of the intermediate layers is large, and thus potential vorticity is correspondingly low, in Oyashio, Okhotsk Sea Mode Water, and Upstream Oyashio. Around the mesothermal (temperature maximum) water, isopycnal potential temperature are low in the areas on the Pacific side, and high in the intermediate layer of Okhotsk Sea Mode Water. The mixing ratio of Okhotsk Sea Mode Water in the Upstream Oyashio water is high. These bidecadal oscillations can be explained by changes in the vertical mixing around the Kuril Straits induced by the diurnal tide whose amplitude is modulated with the 18.6-year nodal cycle. Higher sea surface salinity water around the Kuril Straits caused by stronger tidal mixing is possibly transported northward along the cyclonic Okhotsk Sea Gyre, and possibly enhances the formation of the dense shelf water. This makes apparent oxygen utilization, phosphate, and potential vorticity lower in Okhotsk Sea Mode Water and Oyashio.
Modern Radiation Therapy for Nodal Non-Hodgkin Lymphoma—Target Definition and Dose Guidelines From the International Lymphoma Radiation Oncology Group
Illidge, Tim; Specht, Lena; Yahalom, Joachim; Aleman, Berthe; Berthelsen, Anne Kiil; Constine, Louis; Dabaja, Bouthaina; Dharmarajan, Kavita; Ng, Andrea; Ricardi, Umberto; Wirth, Andrew
Radiation therapy (RT) is the most effective single modality for local control of non-Hodgkin lymphoma (NHL) and is an important component of therapy for many patients. Many of the historic concepts of dose and volume have recently been challenged by the advent of modern imaging and RT planning tools. The International Lymphoma Radiation Oncology Group (ILROG) has developed these guidelines after multinational meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the ILROG steering committee on the use of RT in NHL in the modern era. The roles of reduced volume and reduced doses are addressed, integrating modern imaging with 3-dimensional planning and advanced techniques of RT delivery. In the modern era, in which combined-modality treatment with systemic therapy is appropriate, the previously applied extended-field and involved-field RT techniques that targeted nodal regions have now been replaced by limiting the RT to smaller volumes based solely on detectable nodal involvement at presentation. A new concept, involved-site RT, defines the clinical target volume. For indolent NHL, often treated with RT alone, larger fields should be considered. Newer treatment techniques, including intensity modulated RT, breath holding, image guided RT, and 4-dimensional imaging, should be implemented, and their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control.
Modern radiation therapy for nodal non-Hodgkin lymphoma-target definition and dose guidelines from the International Lymphoma Radiation Oncology Group.
Illidge, Tim; Specht, Lena; Yahalom, Joachim; Aleman, Berthe; Berthelsen, Anne Kiil; Constine, Louis; Dabaja, Bouthaina; Dharmarajan, Kavita; Ng, Andrea; Ricardi, Umberto; Wirth, Andrew
Radiation therapy (RT) is the most effective single modality for local control of non-Hodgkin lymphoma (NHL) and is an important component of therapy for many patients. Many of the historic concepts of dose and volume have recently been challenged by the advent of modern imaging and RT planning tools. The International Lymphoma Radiation Oncology Group (ILROG) has developed these guidelines after multinational meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the ILROG steering committee on the use of RT in NHL in the modern era. The roles of reduced volume and reduced doses are addressed, integrating modern imaging with 3-dimensional planning and advanced techniques of RT delivery. In the modern era, in which combined-modality treatment with systemic therapy is appropriate, the previously applied extended-field and involved-field RT techniques that targeted nodal regions have now been replaced by limiting the RT to smaller volumes based solely on detectable nodal involvement at presentation. A new concept, involved-site RT, defines the clinical target volume. For indolent NHL, often treated with RT alone, larger fields should be considered. Newer treatment techniques, including intensity modulated RT, breath holding, image guided RT, and 4-dimensional imaging, should be implemented, and their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control.
On mechanisms triggering the levees failure along the Foenna stream on 1st January 2006 and which caused the flooding in the urban area of Sinalunga, Tuscany Region (Italy). A case study
NASA Astrophysics Data System (ADS)
Camici, Stefania; Moramarco, Tommaso; Brocca, Luca; Melone, Florisa; Lapenna, Vincenzo; Perrone, Angela; Loperte, Antonio
On 1st January 2006, during an ordinary flood event, a levee failure along the Foenna stream caused the flooding in the urban area of Sinalunga, a small town located in Tuscany region (Italy). The event was monitored by a public agency with the responsibility for the control and maintenance of the natural channel networks. Long time before of flooding, people living in the surrounding area of the stream blamed the presence of wild animals and of numerous burrows along the levees. Although the numerous actions of maintenance along the levees mainly for removing the burrows, a levee seepage occurred during that flood. The presence of an outflow located on the downstream face, almost 2 m below the levee top, caused the spurt of brown water denoting the presence of sediment erosion. On the upstream face of levee, a little hole of about 30 cm at the same height of the outflow was discovered. Although the agency workers tried to close the hole by using appropriate blankets, in short time the top of the levee subsided and the overtopping flow caused a trapezoidal breach typical for an earth-fill embankment. The formation of breach was so fast that in a little more of one hour the urban area near to the Foenna stream was flooded causing high economic damages. Mechanisms triggered the levees failure are the object of this work. The analysis of the event has been first addressed to assess the state of-fact of levees conditions along the Foenna stream, thus to understand how much the activity of wild animals, in particular that of porcupine, may have affected the hydraulic safety of the embankment. At the purpose, after the event, topographical surveys of cross sections have been done along with tomographic surveys by geoelectric technique for investigating the possible presence, besides of burrows, also of tunnels dug into the levees by animals. Then, the analysis of hydrometeorological conditions of the event has allowed to better understand the evolution of the flood and
Development of a Nodal Method for the Solution of the Neutron Diffusion Equation in General Cylindrical Geometry
Ougouag, Abderrafi Mohammed-El-Ami; Terry, William Knox
The usual strategy for solving the neutron diffusion equation in two or three dimensions by nodal methods is to reduce the multidimensional partial differential equation to a set of ordinary differential equations (ODEs) in the separate spatial coordinates. This reduction is accomplished by "transverse integration" of the equation.1 For example, in three-dimensional Cartesian coordinates, the three-dimensional equation is first integrated over x and y to obtain an ODE in z, then over x and z to obtain an ODE in y, and finally over y and z to obtain an ODE in x. Then the ODEs are solved to obtain onedimensional solutions for the neutron fluxes averaged over the other two dimensions. These solutions are found in regions ("nodes") small enough for the material properties and cross sections in them to be adequately represented by average values. Because the solution in each node is an exact analytical solution, the nodes can be much larger than the mesh elements used in finite-difference solutions. Then the solutions in the different nodes are coupled by applying interface conditions, ultimately fixing the solutions to the external boundary conditions.
GABAergic neurons of the medial septum play a nodal role in facilitation of nociception-induced affect
Ang, Seok Ting; Lee, Andy Thiam Huat; Foo, Fang Chee; Ng, Lynn; Low, Chian-Ming; Khanna, Sanjay
The present study explored the functional details of the influence of medial septal region (MSDB) on spectrum of nociceptive behaviours by manipulating intraseptal GABAergic mechanisms. Results showed that formalin-induced acute nociception was not affected by intraseptal microinjection of bicuculline, a GABAA receptor antagonist, or on selective lesion of septal GABAergic neurons. Indeed, the acute nociceptive responses were dissociated from the regulation of sensorimotor behaviour and generation of theta-rhythm by the GABAergic mechanisms in MSDB. The GABAergic lesion attenuated formalin-induced unconditioned cellular response in the anterior cingulate cortex (ACC) and blocked formalin-induced conditioned place avoidance (F-CPA), and as well as the contextual fear induced on conditioning with brief footshock. The effects of lesion on nociceptive-conditioned cellular responses were, however, variable. Interestingly, the lesion attenuated the conditioned representation of experimental context in dorsal hippocampus field CA1 in the F-CPA task. Collectively, the preceding suggests that the MSDB is a nodal centre wherein the GABAergic neurons mediate nociceptive affect-motivation by regulating cellular mechanisms in ACC that confer an aversive value to the noxious stimulus. Further, in conjunction with a modulatory influence on hippocampal contextual processing, MSDB may integrate affect with context as part of associative learning in the F-CPA task. PMID:26487082
GABAergic neurons of the medial septum play a nodal role in facilitation of nociception-induced affect.
Ang, Seok Ting; Lee, Andy Thiam Huat; Foo, Fang Chee; Ng, Lynn; Low, Chian-Ming; Khanna, Sanjay
The present study explored the functional details of the influence of medial septal region (MSDB) on spectrum of nociceptive behaviours by manipulating intraseptal GABAergic mechanisms. Results showed that formalin-induced acute nociception was not affected by intraseptal microinjection of bicuculline, a GABAA receptor antagonist, or on selective lesion of septal GABAergic neurons. Indeed, the acute nociceptive responses were dissociated from the regulation of sensorimotor behaviour and generation of theta-rhythm by the GABAergic mechanisms in MSDB. The GABAergic lesion attenuated formalin-induced unconditioned cellular response in the anterior cingulate cortex (ACC) and blocked formalin-induced conditioned place avoidance (F-CPA), and as well as the contextual fear induced on conditioning with brief footshock. The effects of lesion on nociceptive-conditioned cellular responses were, however, variable. Interestingly, the lesion attenuated the conditioned representation of experimental context in dorsal hippocampus field CA1 in the F-CPA task. Collectively, the preceding suggests that the MSDB is a nodal centre wherein the GABAergic neurons mediate nociceptive affect-motivation by regulating cellular mechanisms in ACC that confer an aversive value to the noxious stimulus. Further, in conjunction with a modulatory influence on hippocampal contextual processing, MSDB may integrate affect with context as part of associative learning in the F-CPA task.
Are Radiation Therapy Oncology Group Para-aortic Contouring Guidelines for Pancreatic Neoplasm Applicable to Other Malignancies—Assessment of Nodal Distribution in Gynecological Malignancies
Kabolizadeh, Peyman; Fulay, Suyash; Beriwal, Sushil
Purpose: Intensity modulated radiation therapy is used to reduce dose to adjacent critical structures while maintaining adequate target coverage, but it requires precise target localization. We report the 3-dimensional distribution of para-aortic (PA) lymph nodes (LN) in pelvic malignancies. We propose a guideline to accurately define the PA LN by anatomic landmarks and compare our data with published guidelines for pancreatic cancer. Methods and Materials: A retrospective analysis was performed on 46 patients with pelvic malignancies and positive PA LNs. Positive LNs were defined based on size and morphology or fluorodeoxyglucose avidity. All PA LNs were characterized into 3 groups based on location: left PA (between aorta and left psoas muscle), aortocaval (between aorta and inferior vena cava), and right paracaval (between inferior vena cava and right psoas muscle). Patients with retrocrural LNs were also analyzed. Results: One hundred thirty-three positive PA LNs were evaluated. The majority of the PA LNs were in the left PA (59%) and aortocaval (35) regions, and only 8% were in the right paracaval region. All patients with positive right paracaval LNs also had involved left PA LNs, with only 1 exception. The highest PA LN involvement was at the level of the renal vessels and was seen in 28% of patients. Of these patients with disease extending to renal vessels, 38% had retrocrural LN involvement. Conclusions: The nodal contouring for the PA region should not be defined by a fixed circumferential margin around the vessels. The left PA and aortocaval spaces should be covered adequately because these are common locations of PA LNs. For microscopic disease superiorly, contouring should extend up to renal vessels rather than a fixed bony landmark. For patients who have nodal involvement at renal vessels, one can consider including retrocrural LNs. Radiation Therapy Oncology Group Para-aortic Contouring Guidelines for Pancreatic Neoplasm are not applicable to
Integrated rate-dependent and dual pathway AV nodal functions: principles and assessment framework.
Billette, Jacques; Tadros, Rafik
The atrioventricular (AV) node conducts slowly and has a long refractory period. These features sustain the filtering of atrial impulses and hence are often modulated to optimize ventricular rate during supraventricular tachyarrhythmias. The AV node is also the site of a clinically common reentrant arrhythmia. Its function is assessed for a variety of purposes from its responses to a premature protocol (S1S2, test beats introduced at different cycle lengths) repeatedly performed at different basic rates and/or to an incremental pacing protocol (increasingly faster rates). Puzzlingly, resulting data and interpretation differ with protocols as well as with chosen recovery and refractory indexes, and are further complicated by the presence of built-in fast and slow pathways. This problem applies to endocavitary investigations of arrhythmias as well as to many experimental functional studies. This review supports an integrated framework of rate-dependent and dual pathway AV nodal function that can account for these puzzling characteristics. The framework was established from AV nodal responses to S1S2S3 protocols that, compared with standard S1S2 protocols, allow for an orderly quantitative dissociation of the different factors involved in changes in AV nodal conduction and refractory indexes under rate-dependent and dual pathway function. Although largely based on data from experimental studies, the proposed framework may well apply to the human AV node. In conclusion, the rate-dependent and dual pathway properties of the AV node can be integrated within a common functional framework the contribution of which to individual responses can be quantitatively determined with properly designed protocols and analytic tools.
Relativity mission with two counter-orbiting polar satellites. [nodal dragging effect on earth orbiting satellites
NASA Technical Reports Server (NTRS)
Van Patten, R. A.; Everitt, C. W. F.
In 1918, J. Lense and H. Thirring calculated that a moon in orbit around a massive rotating planet would experience a nodal dragging effect due to general relativity. We describe an experiment to measure this effect with two counter-orbiting drag-free satellites in polar earth orbit. For a 2 1/2 year experiment, the measurement accuracy should approach 1%. In addition to precision tracking data from existing ground stations, satellite-to-satellite Doppler ranging data are taken at points of passing near the poles. New geophysical information on both earth harmonics and tidal effects is inherent in the polar ranging data.
Light Spectral Quality Effects on the Growth of Potato (Solanum Tuberosum L.) Nodal Cutttings in Vitro
NASA Technical Reports Server (NTRS)
Wilson, Deborah A.; Weigel, Russell, C.; Wheeler, Raymond M.; Sager, John C.
The effects of light spectral quality on the growth of in vitro nodal cutting of potato (Solanum tuberosum) cultivars Norland, Superior, Kennebec, and Denali were examined. The different light spectra were provided by Vita-Lite fluorescent (VF) (a white light control), blue fluorescent (BF), red fluorescent (RF), low-pressure sodium (LPS), and a combination of low-pressure sodium plus cool-white fluorescent lamp (LPS/CWF). Results suggested that shoot morphologic development of in vitro grown potato plants can be controlled by controlling irradiant spectral quality.
Evaluation of a Stirling engine heater bypass with the NASA Lewis nodal-analysis performance code
Sullivan, T.J.
In support of the US Department of Energy's Stirling Engine Highway Vehicle Systems program, the NASA Lewis Research Center investigated whether bypassing the P-40 Stirling engine heater during regenerative cooling would improve the engine thermal efficiency. The investigation was accomplished by using the Lewis nodal-analysis Stirling engine computer model. Bypassing the P-40 Stirling engine heater at full power resulted in a rise in the indicated thermal efficiency from 40.6 to 41.0 percent. For the idealized (some losses not included) heater bypass that was analyzed, this benefit is not considered significant.
Statistics of nodal points of in-plane random waves in elastic media.
Maksimov, Dmitrii N; Sadreev, Almas F
We consider the nodal points (NPs) u=0 and v=0 of the in-plane vectorial displacements u=(u,v) which obey the Navier-Cauchy equation. Similar to the Berry conjecture of quantum chaos, we present the in-plane eigenstates of chaotic billiards as the real part of the superposition of longitudinal and transverse plane waves with random phases. By an average over random phases we derive the mean density and correlation function of NPs. Consequently we consider the distribution of the nearest distances between NPs.
PoroTomo Subtask 6.3 Nodal Seismometer Earthquake Data
Kurt Feigl
90-second records of data from 238 three-component nodal seismometer deployed at Bradys geothermal field. The time window catches an earthquake arrival. Earthquake data from USGS online catalog: Magnitude: 4.3 ml ± 0.4 Location: 38.479°N 118.366°W ± 0.7 km Depth: 9.9 km ± 0.7 Date and Time: 2016-03-21 07:37:10.535 UTC http://earthquake.usgs.gov/earthquakes/eventpage/nn00536374#executive
Nodal quasiparticles and the onset of spin-density-wave order in cuprate superconductors.
Pelissetto, Andrea; Sachdev, Subir; Vicari, Ettore
We present a theory for the onset of spin-density-wave order in the superconducting ground state of the cuprates. We compute the scaling dimensions of allowed perturbations of a "relativistic" fixed point with O4 x O(3) symmetry, including those associated with the fermionic nodal Bogoliubov quasiparticles. Analyses of up to six loops show that all perturbations with square lattice symmetry are likely irrelevant. We demonstrate that the fermion spectral functions are primarily damped by the coupling to fluctuations of a composite field with Ising nematic order. A number of other experimental implications are also discussed.
Kidney failure; Renal failure; Renal failure - acute; ARF; Kidney injury - acute ... There are many possible causes of kidney damage. They include: ... cholesterol (cholesterol emboli) Decreased blood flow due to very ...
... page from the NHLBI on Twitter. What Is Heart Failure? Heart failure is a condition in which the heart can' ... force. Some people have both problems. The term "heart failure" doesn't mean that your heart has stopped ...
Poor understanding of the hydrogeological structure is a main cause of hand-dug wells failure in developing countries: A case study of a Precambrian basement aquifer in Bugesera region (Burundi)
NASA Astrophysics Data System (ADS)
Bakundukize, Charles; Mtoni, Yohana; Martens, Kristine; Van Camp, Marc; Walraevens, Kristine
This study investigates a Precambrian basement aquifer in Bugesera region, a typical African rural area in northeastern Burundi. Domestic water supply relies on groundwater which is tapped through hand-dug wells. Despite several attempts to increase the number of water points in the area, the water demand is still far from being met as a result of the high rate of well failure. This paper seeks to understand whether the hydrogeological structure and the spatial distribution of hydraulic parameters can explain the low productivity and the high failure rate of hand-dug wells. The hydrogeological structure inferred from the interpretation of a large number of vertical electrical soundings (VES) reveals a typical sequence of geoelectrical layers, which is characterized by an overall upwards fining from the fresh basement, over the fractured/weathered basement, to the overburden or saprolite with a clay-rich layer on top. Whereas the overall aquifer potential mainly depends on the thickness of the weathered overburden, the aquifer potential for shallow hand-dug wells is determined by the hydraulic conductivity of the upper few meters of the saturated zone. This upper zone was investigated in the pumping tests. The spatial distribution of the specific capacity reveals a wide variation of hydraulic parameters, depending on the well's position in the depth profile of the aquifer's hydraulic conductivity. The thickness of the potential aquifer is highest in the central part of the study area (pegmatitic and granitic intrusions) which has the highest overall aquifer potential compared to the surrounding metasedimentary formations. However, a thick weathered overburden will increase the groundwater potential of an aquifer for deep boreholes, whereas for hand-dug wells, the productivity can only be high if the thickness of the weathered overburden is small enough, or the water table is deep enough, to allow to tap the coarse part at the base of the overburden and/or part of
Failure of oral penicillin as secondary prophylaxis for rheumatic heart disease: a lesson from a low-prevalence rheumatic fever region.
McGlacken-Byrne, S M; Parry, H M; Currie, P F; Wilson, N J
Our patient is an 18-year-old Caucasian woman from the UK who developed severe mitral stenosis on a history of childhood acute rheumatic fever (ARF) and rheumatic heart disease (RHD). She had been reporting of her oral penicillin secondary prophylaxis regimen since diagnosis. At the age of 15 years, a new murmur was discovered during routine cardiac follow-up. An echocardiogram confirmed moderate-severe mitral stenosis. One year later, her exercise tolerance significantly deteriorated and she subsequently underwent balloon valvuloplasty of her mitral valve to good effect. Our case emphasises the evidence base supporting the use of monthly intramuscular penicillin injection to prevent ARF recurrence and RHD progression; it also emphasises the reduced efficacy of oral penicillin prophylaxis in this context. It particularly resonates with regions of low rheumatic fever endemicity. The long-term cardiac sequelae of ARF can be devastating; prescribing the most effective secondary prophylaxis regimen is essential.
Nodal promotes the self-renewal of human colon cancer stem cells via an autocrine manner through Smad2/3 signaling pathway.
Gong, Yuehua; Guo, Ying; Hai, Yanan; Yang, Hao; Liu, Yang; Yang, Shi; Zhang, Zhenzhen; Ma, Meng; Liu, Linhong; Li, Zheng; He, Zuping
Colorectal cancer is one of the most common and fatal tumors. However, molecular mechanisms underlying carcinogenesis of colorectal cancer remain largely undefined. Here, we explored the expression and function of Nodal in colon cancer stem cells (CCSCs). Nodal and its receptors were present in numerous human colorectal cancer cell lines. NODAL and ALK-4 were coexpressed in human colon cancerous tissues, and NODAL, CD24, and CD44, markers for CCSCs, were expressed at higher levels in human colon cancerous tissues than adjacent noncancerous colon tissues. Human CCSCs were isolated by magnetic activated cell sorting using anti-CD24 and anti-CD44. Nodal transcript and protein were hardly detectable in CD44- or CD24-negative human colorectal cancer cell lines, whereas Nodal and its receptors were present in CCSCs. Notably, Nodal facilitated spheroid formation of human CCSCs, and phosphorylation of Smad2 and Smad3 was activated by Nodal in cells of spheres derived from human CCSCs. Collectively, these results suggest that Nodal promotes the self-renewal of human CCSCs and mediate carcinogenesis of human colorectal cancer via an autocrine manner through Smad2/3 pathway. This study provides a novel insight into molecular mechanisms controlling fate of human CCSCs and offers new targets for gene therapy of human colorectal cancer.
Activin/Nodal signaling controls divergent transcriptional networks in human embryonic stem cells and in endoderm progenitors.
Brown, Stephanie; Teo, Adrian; Pauklin, Siim; Hannan, Nicholas; Cho, Candy H-H; Lim, Bing; Vardy, Leah; Dunn, N Ray; Trotter, Matthew; Pedersen, Roger; Vallier, Ludovic
Activin/Nodal signaling is necessary to maintain pluripotency of human embryonic stem cells (hESCs) and to induce their differentiation toward endoderm. However, the mechanisms by which Activin/Nodal signaling achieves these opposite functions remain unclear. To unravel these mechanisms, we examined the transcriptional network controlled in hESCs by Smad2 and Smad3, which represent the direct effectors of Activin/Nodal signaling. These analyses reveal that Smad2/3 participate in the control of the core transcriptional network characterizing pluripotency, which includes Oct-4, Nanog, FoxD3, Dppa4, Tert, Myc, and UTF1. In addition, similar experiments performed on endoderm cells confirm that a broad part of the transcriptional network directing differentiation is downstream of Smad2/3. Therefore, Activin/Nodal signaling appears to control divergent transcriptional networks in hESCs and in endoderm. Importantly, we observed an overlap between the transcriptional network downstream of Nanog and Smad2/3 in hESCs; whereas, functional studies showed that both factors cooperate to control the expression of pluripotency genes. Therefore, the effect of Activin/Nodal signaling on pluripotency and differentiation could be dictated by tissue specific Smad2/3 partners such as Nanog, explaining the mechanisms by which signaling pathways can orchestrate divergent cell fate decisions.
Evidence of Topological Nodal-Line Fermions in ZrSiSe and ZrSiTe
NASA Astrophysics Data System (ADS)
Hu, Jin; Tang, Zhijie; Liu, Jinyu; Liu, Xue; Zhu, Yanglin; Graf, David; Myhro, Kevin; Tran, Son; Lau, Chun Ning; Wei, Jiang; Mao, Zhiqiang
A Dirac nodal-line semimetal phase, which represents a new quantum state of topological materials, has been experimentally realized only in a few systems, including PbTaSe2 , PtSn4 , and ZrSiS. In this Letter, we report evidence of nodal-line fermions in ZrSiSe and ZrSiTe probed in de Haas-van Alphen quantum oscillations. Although ZrSiSe and ZrSiTe share a similar layered structure with ZrSiS, our studies show the Fermi surface (FS) enclosing a Dirac nodal line has a 2D character in ZrSiTe, in contrast with 3D-like FS in ZrSiSe and ZrSiS. Another important property revealed in our experiment is that the nodal-line fermion density in this family of materials (˜1020 cm-3 ) is much higher than the Dirac fermion density of other topological materials with discrete nodes. In addition, we have demonstrated ZrSiSe and ZrSiTe single crystals can be thinned down to 2D atomic thin layers through microexfoliation, which offers the first platform to explore exotic properties of topological nodal-line fermions in low dimensions.
Evidence of Topological Nodal-Line Fermions in ZrSiSe and ZrSiTe.
Hu, Jin; Tang, Zhijie; Liu, Jinyu; Liu, Xue; Zhu, Yanglin; Graf, David; Myhro, Kevin; Tran, Son; Lau, Chun Ning; Wei, Jiang; Mao, Zhiqiang
A Dirac nodal-line semimetal phase, which represents a new quantum state of topological materials, has been experimentally realized only in a few systems, including PbTaSe_{2}, PtSn_{4}, and ZrSiS. In this Letter, we report evidence of nodal-line fermions in ZrSiSe and ZrSiTe probed in de Haas-van Alphen quantum oscillations. Although ZrSiSe and ZrSiTe share a similar layered structure with ZrSiS, our studies show the Fermi surface (FS) enclosing a Dirac nodal line has a 2D character in ZrSiTe, in contrast with 3D-like FS in ZrSiSe and ZrSiS. Another important property revealed in our experiment is that the nodal-line fermion density in this family of materials (∼10^{20} cm^{-3}) is much higher than the Dirac fermion density of other topological materials with discrete nodes. In addition, we have demonstrated ZrSiSe and ZrSiTe single crystals can be thinned down to 2D atomic thin layers through microexfoliation, which offers the first platform to explore exotic properties of topological nodal-line fermions in low dimensions.
Evaluation of intracardiac recordings in diagnosis of impulse formation and concealed conduction in atrioventricular nodal bypass tracts.
Castellanos, A; Agha, A S; Mendoza, I J; Sung, R J
Invasive electrophysiological studies were performed in 2 symptomatic patients with recurrent arrhythmias in which impulse formation presumably occured within atrioventricular nodal bypass tracts. Case 1 had ectopic beats arising within, or close to, the upper end of a left-sided atrioventricular nodal bypass tract of the type described by Brechenmacher. In addition, this conduction was 'concealed' during sinus rhythm and right atrial pacing because the relatively prolonged right-to-left atrial conduction time allowed right atrial impulses to reach the His bundle via the atrioventricular node before they could do so through the atrioventricular nodal bypass tract. Case 2 had ectopic beats arising in a right-sided atrioventricular nodal bypass tract which did not conduct in either forward or retrograde directions, its presence being detected only when initiating impulses. However, it could not be determined whether this tract was an 'abnormal' atrio-His connection or a 'normal' transitional (atrio-atrioventricular nodal) tract. Though intracardiac studies complement body surface recordings, they should be interpreted with knowledge of their inherent limitations. PMID:884022
CHF - medicines; Congestive heart failure - medicines; Cardiomyopathy - medicines; HF - medicines ... You will need to take most of your heart failure medicines every day. Some medicines are taken ...
Anisotropic Failure Modeling for HY-100 Steel
NASA Astrophysics Data System (ADS)
Harstad, E. N.; Maudlin, P. J.; McKirgan, J. B.
HY-100 steel is a material that behaves isotropically in the elastic and plastic region and acts anisotropically in failure. Since HY-100 is a ductile metal, a more gradual failure process is observed as opposed to the nearly instantaneous failure in brittle materials. We extend our elasto-plastic-damage constitutive model by including of a decohesion model to describe material behavior between the onset of failure and fracture. We also develop an anisotropic failure surface to account for directionality in material failure. Both the anisotropic failure and decohesion models have been implemented into a finite element code, where the effects of these models are studied in a uniaxial stress simulations, a plate impact simulations, and a quasistatic notched round bar tensile test simulations.
Analyses of Transistor Punchthrough Failures
NASA Technical Reports Server (NTRS)
Nicolas, David P.
The failure of two transistors in the Altitude Switch Assembly for the Solid Rocket Booster followed by two additional failures a year later presented a challenge to failure analysts. These devices had successfully worked for many years on numerous missions. There was no history of failures with this type of device. Extensive checks of the test procedures gave no indication for a source of the cause. The devices were manufactured more than twenty years ago and failure information on this lot date code was not readily available. External visual exam, radiography, PEID, and leak testing were performed with nominal results Electrical testing indicated nearly identical base-emitter and base-collector characteristics (both forward and reverse) with a low resistance short emitter to collector. These characteristics are indicative of a classic failure mechanism called punchthrough. In failure analysis punchthrough refers to an condition where a relatively low voltage pulse causes the device to conduct very hard producing localized areas of thermal runaway or "hot spots". At one or more of these hot spots, the excessive currents melt the silicon. Heavily doped emitter material diffuses through the base region to the collector forming a diffusion pipe shorting the emitter to base to collector. Upon cooling, an alloy junction forms between the pipe and the base region. Generally, the hot spot (punch-through site) is under the bond and no surface artifact is visible. The devices were delidded and the internal structures were examined microscopically. The gold emitter lead was melted on one device, but others had anomalies in the metallization around the in-tact emitter bonds. The SEM examination confirmed some anomalies to be cosmetic defects while other anomalies were artifacts of the punchthrough site. Subsequent to these analyses, the contractor determined that some irregular testing procedures occurred at the time of the failures heretofore unreported. These testing
Oyster Creek cycle 10 nodal model parameter optimization study using PSMS
Dougher, J.D.
The power shape monitoring system (PSMS) is an on-line core monitoring system that uses a three-dimensional nodal code (NODE-B) to perform nodal power calculations and compute thermal margins. The PSMS contains a parameter optimization function that improves the ability of NODE-B to accurately monitor core power distributions. This functions iterates on the model normalization parameters (albedos and mixing factors) to obtain the best agreement between predicted and measured traversing in-core probe (TIP) reading on a statepoint-by-statepoint basis. Following several statepoint optimization runs, an average set of optimized normalization parameters can be determined and can be implemented into the current or subsequent cycle core model for on-line core monitoring. A statistical analysis of 19 high-power steady-state state-points throughout Oyster Creek cycle 10 operation has shown a consistently poor virgin model performance. The normalization parameters used in the cycle 10 NODE-B model were based on a cycle 8 study, which evaluated only Exxon fuel types. The introduction of General Electric (GE) fuel into cycle 10 (172 assemblies) was a significant fuel/core design change that could have altered the optimum set of normalization parameters. Based on the need to evaluate a potential change in the model normalization parameters for cycle 11 and in an attempt to account for the poor cycle 10 model performance, a parameter optimization study was performed.
Cooperative Wnt-Nodal Signals Regulate the Patterning of Anterior Neuroectoderm
Yaguchi, Junko; Takeda, Noriyo; Inaba, Kazuo; Yaguchi, Shunsuke
When early canonical Wnt is experimentally inhibited, sea urchin embryos embody the concept of a Default Model in vivo because most of the ectodermal cell fates are specified as anterior neuroectoderm. Using this model, we describe here how the combination of orthogonally functioning anteroposterior Wnt and dorsoventral Nodal signals and their targeting transcription factors, FoxQ2 and Homeobrain, regulates the precise patterning of normal neuroectoderm, of which serotonergic neurons are differentiated only at the dorsal/lateral edge. Loss-of-function experiments revealed that ventral Nodal is required for suppressing the serotonergic neural fate in the ventral side of the neuroectoderm through the maintenance of foxQ2 and the repression of homeobrain expression. In addition, non-canonical Wnt suppressed homeobrain in the anterior end of the neuroectoderm, where serotonergic neurons are not differentiated. Canonical Wnt, however, suppresses foxQ2 to promote neural differentiation. Therefore, the three-dimensionally complex patterning of the neuroectoderm is created by cooperative signals, which are essential for the formation of primary and secondary body axes during embryogenesis. PMID:27101101
Misalignment-induced nodal aberration fields in two-mirror astronomical telescopes.
Schmid, Tobias; Thompson, Kevin P; Rolland, Jannick P
We present the effects of misalignments on the field dependence of the third-order aberration fields of traditional, two-mirror astronomical telescopes in the context of nodal aberration theory, which we believe is the most general and extensible framework for describing and improving on-station performance. While many of the advantages of nodal aberration theory, compared to other, often power series expansion-based descriptions of misalignment effects on aberrations, become particularly important when analyzing telescopes with more than two mirrors, or in the presence of figure errors; this paper aims to provide and demonstrate the fundamental concepts needed to fully describe the state of correction of misaligned two-mirror telescopes. Importantly, it is shown that the assumption that perfect performance on axis ensures a fully aligned telescope is false, and we demonstrate that if Ritchey-Chrétien telescopes are aligned for zero coma on axis as the sole criterion, formidable misalignments will likely remain, leading to image quality degradation, particularly beyond midfield caused by astigmatism with binodal field dependence (i.e., astigmatism goes to zero at two points in the field).
Reflector modelling of small high leakage cores making use of multi-group nodal equivalence theory
Theron, S. A.; Reitsma, F.
This research focuses on modelling reflectors in typical material testing reactors (MTRs). Equivalence theory is used to homogenise and collapse detailed transport solutions to generate equivalent nodal parameters and albedo boundary conditions for reflectors, for subsequent use in full core nodal diffusion codes. This approach to reflector modelling has been shown to be accurate for two-group large commercial light water reactor (LWR) analysis, but has not been investigated for MTRs. MTRs are smaller, with much larger leakage, environment sensitivity and multi-group spectrum dependencies than LWRs. This study aims to determine if this approach to reflector modelling is an accurate and plausible homogenisation technique for the modelling of small MTR cores. The successful implementation will result in simplified core models, better accuracy and improved efficiency of computer simulations. Codes used in this study include SCALE 6.1, OSCAR-4 and EQUIVA (the last two codes are developed and used at Necsa). The results show a five times reduction in calculational time for the proposed reduced reactor model compared to the traditional explicit model. The calculated equivalent parameters however show some sensitivity to the environment used to generate them. Differences in the results compared to the current explicit model, require more careful investigation including comparisons with a reference result, before its implementation can be recommended. (authors)
Comparison of Nodal Risk Formula and MR Lymphography for Predicting Lymph Node Involvement in Prostate Cancer
Deserno, Willem M.L.L.G.; Debats, Oscar A.; Rozema, Tom; Fortuin, Ansje S.; Heesakkers, Roel A.M.; Hoogeveen, Yvonne; Peer, Petronella G.M.; Barentsz, Jelle O.; Lin, Emile N.J.T. van
Purpose: To compare the nodal risk formula (NRF) as a predictor for lymph node (LN) metastasis in patients with prostate cancer with magnetic resonance lymphography (MRL) using Ultrasmall Super-Paramagnetic particles of Iron Oxide (USPIO) and with histology as gold standard. Methods and Materials: Logistic regression analysis was performed with the results of histopathological evaluation of the LN as dependent variable and the nodal risk according to the NRF and the result of MRL as independent input variables. Receiver operating characteristic (ROC) analysis was performed to assess the performance of the models. Results: The analysis included 375 patients. In the single-predictor regression models, the NRF and MRL results were both significantly (p <0.001) predictive of the presence of LN metastasis. In the models with both predictors included, NRF was nonsignificant (p = 0.126), but MRL remained significant (p <0.001). For NRF, sensitivity was 0.79 and specificity was 0.38; for MRL, sensitivity was 0.82 and specificity was 0.93. After a negative MRL result, the probability of LN metastasis is 4% regardless of the NRF result. After a positive MRL, the probability of having LN metastasis is 68%. Conclusions: MRL is a better predictor of the presence of LN metastasis than NRF. Using only the NRF can lead to a significant overtreatment on the pelvic LN by radiation therapy. When the MRL result is available, the NRF is no longer of added value.
A generalized framework for nodal first derivative summation-by-parts operators
NASA Astrophysics Data System (ADS)
Del Rey Fernández, David C.; Boom, Pieter D.; Zingg, David W.
A generalized framework is presented that extends the classical theory of finite-difference summation-by-parts (SBP) operators to include a wide range of operators, where the main extensions are (i) non-repeating interior point operators, (ii) nonuniform nodal distribution in the computational domain, (iii) operators that do not include one or both boundary nodes. Necessary and sufficient conditions are proven for the existence of nodal approximations to the first derivative with the SBP property. It is proven that the positive-definite norm matrix of each SBP operator must be associated with a quadrature rule; moreover, given a quadrature rule there exists a corresponding SBP operator, where for diagonal-norm SBP operators the weights of the quadrature rule must be positive. The generalized framework gives a straightforward means of posing many known approximations to the first derivative as SBP operators; several are surveyed, such as discontinuous Galerkin discretizations based on the Legendre-Gauss quadrature points, and shown to be SBP operators. Moreover, the new framework provides a method for constructing SBP operators by starting from quadrature rules; this is illustrated by constructing novel SBP operators from known quadrature rules. To demonstrate the utility of the generalization, the Legendre-Gauss and Legendre-Gauss-Radau quadrature points are used to construct SBP operators that do not include one or both boundary nodes.
Conservation defines functional motifs in the squint/nodal-related 1 RNA dorsal localization element
Gilligan, Patrick C.; Kumari, Pooja; Lim, Shimin; Cheong, Albert; Chang, Alex; Sampath, Karuna
RNA localization is emerging as a general principle of sub-cellular protein localization and cellular organization. However, the sequence and structural requirements in many RNA localization elements remain poorly understood. Whereas transcription factor-binding sites in DNA can be recognized as short degenerate motifs, and consensus binding sites readily inferred, protein-binding sites in RNA often contain structural features, and can be difficult to infer. We previously showed that zebrafish squint/nodal-related 1 (sqt/ndr1) RNA localizes to the future dorsal side of the embryo. Interestingly, mammalian nodal RNA can also localize to dorsal when injected into zebrafish embryos, suggesting that the sequence motif(s) may be conserved, even though the fish and mammal UTRs cannot be aligned. To define potential sequence and structural features, we obtained ndr1 3′-UTR sequences from approximately 50 fishes that are closely, or distantly, related to zebrafish, for high-resolution phylogenetic footprinting. We identify conserved sequence and structural motifs within the zebrafish/carp family and catfish. We find that two novel motifs, a single-stranded AGCAC motif and a small stem-loop, are required for efficient sqt RNA localization. These findings show that comparative sequencing in the zebrafish/carp family is an efficient approach for identifying weak consensus binding sites for RNA regulatory proteins. PMID:21149265
The lunar nodal tide and the distance to tne Moon during the Precambrian era
NASA Technical Reports Server (NTRS)
Walker, J. C. G.; Zahnle, K. J.
The origin and early evolution of life on Earth occurred under physical and chemical conditions distinctly different from those of the present day. The broad goal of this research program is to characterize these conditions. One aspect involves the dynamics of the Earth-Moon system, the distance of the Moon from the Earth, and the length of the day. These have evolved during the course of Earth history as a result of the dissipation of tidal energy. As the moon has receded the amplitude of oceanic tides has decreased while the increasing length of the day should have influenced climate and the circulation of atmosphere and ocean. A 23.3 year periodicity preserved in a 2500 million year old banded iron-formation was interpreted as reflecting the climatic influence of the lunar nodal tide. The corresponding lunar distance would then have been approx. 52 Earth radii. The influence of the lunar nodal tide is also apparent in rocks with an age of 680 million years B.P. The derived value for lunar distance 2500 million years ago is the only datum on the dynamics of the Earth-Moon system during the Precambrian era of Earth history. The implied development of Precambrian tidal friction is in accord with more recent paleontological evidence as well as the long term stability of the lunar orbit.
Nodal bilayer-splitting controlled by spin-orbit interactions in underdoped high-Tc cuprates
Harrison, N.; Ramshaw, B. J.; Shekhter, A.
The highest superconducting transition temperatures in the cuprates are achieved in bilayer and trilayer systems, highlighting the importance of interlayer interactions for high Tc. It has been argued that interlayer hybridization vanishes along the nodal directions by way of a specific pattern of orbital overlap. Recent quantum oscillation measurements in bilayer cuprates have provided evidence for a residual bilayer-splitting at the nodes that is sufficiently small to enable magnetic breakdown tunneling at the nodes. Here we show that several key features of the experimental data can be understood in terms of weak spin-orbit interactions naturally present in bilayer systems, whose primary effect is to cause the magnetic breakdown to be accompanied by a spin flip. These features can now be understood to include the equidistant set of three quantum oscillation frequencies, the asymmetry of the quantum oscillation amplitudes in c-axis transport compared to ab-plane transport, and the anomalous magnetic field angle dependence of the amplitude of the side frequencies suggestive of small effective g-factors. We suggest that spin-orbit interactions in bilayer systems can further affect the structure of the nodal quasiparticle spectrum in the superconducting phase. PACS numbers: 71.45.Lr, 71.20.Ps, 71.18.+y PMID:26039222
Clinical target volume delineation including elective nodal irradiation in preoperative and definitive radiotherapy of pancreatic cancer
Background Radiotherapy (RT) is widely used in the treatment of pancreatic cancer. Currently, recommendation has been given for the delineation of the clinical target volume (CTV) in adjuvant RT. Based on recently reviewed pathologic data, the aim of this study is to propose criteria for the CTV definition and delineation including elective nodal irradiation (ENI) in the preoperative and definitive treatment of pancreatic cancer. Methods The anatomical structures of interest, as well as the abdominal vasculature were identified on intravenous contrast-enhanced CT scans of two different patients with pancreatic cancer of the head and the body. To delineate the lymph node area, a margin of 10 mm was added to the arteries. Results We proposed a set of guidelines for elective treatment of high-risk nodal areas and CTV delineation. Reference CT images were provided. Conclusions The proposed guidelines could be used for preoperative or definitive RT for carcinoma of the head and body of the pancreas. Further clinical investigations are needed to validate the defined CTVs. PMID:22691275
Nodal bilayer-splitting controlled by spin-orbit interactions in underdoped high-Tc cuprates
Harrison, N.; Ramshaw, B. J.; Shekhter, A.
The highest superconducting transition temperatures in the cuprates are achieved in bilayer and trilayer systems, highlighting the importance of interlayer interactions for high Tc. It has been argued that interlayer hybridization vanishes along the nodal directions by way of a specific pattern of orbital overlap. Recent quantum oscillation measurements in bilayer cuprates have provided evidence for a residual bilayer-splitting at the nodes that is sufficiently small to enable magnetic breakdown tunneling at the nodes. Here we show that several key features of the experimental data can be understood in terms of weak spin-orbit interactions naturally present in bilayer systems, whosemore » primary effect is to cause the magnetic breakdown to be accompanied by a spin flip. These features can now be understood to include the equidistant set of three quantum oscillation frequencies, the asymmetry of the quantum oscillation amplitudes in c-axis transport compared to ab-plane transport, and the anomalous magnetic field angle dependence of the amplitude of the side frequencies suggestive of small effective g-factors. We suggest that spin-orbit interactions in bilayer systems can further affect the structure of the nodal quasiparticle spectrum in the superconducting phase. PACS numbers: 71.45.Lr, 71.20.Ps, 71.18.+y« less
Observation of topological nodal fermion semimetal phase in ZrSiS
NASA Astrophysics Data System (ADS)
Neupane, Madhab; Belopolski, Ilya; Hosen, M. Mofazzel; Sanchez, Daniel S.; Sankar, Raman; Szlawska, Maria; Xu, Su-Yang; Dimitri, Klauss; Dhakal, Nagendra; Maldonado, Pablo; Oppeneer, Peter M.; Kaczorowski, Dariusz; Chou, Fangcheng; Hasan, M. Zahid; Durakiewicz, Tomasz
Unveiling new topological phases of matter is one of the current objectives in condensed matter physics. Recent experimental discoveries of Dirac and Weyl semimetals prompt the search for other exotic phases of matter. Here we present a systematic angle-resolved photoemission spectroscopy study of ZrSiS, a prime topological nodal semimetal candidate. Our wider Brillouin zone (BZ) mapping shows multiple Fermi surface pockets such as the diamond-shaped Fermi surface, elliptical-shaped Fermi surface, and a small electron pocket encircling at the zone center (Γ ) point, the M point, and the X point of the BZ, respectively. We experimentally establish the spinless nodal fermion semimetal phase in ZrSiS, which is supported by our first-principles calculations. Our findings evidence that the ZrSiS-type of material family is a new platform on which to explore exotic states of quantum matter; these materials are expected to provide an avenue for engineering two-dimensional topological insulator systems.
Sivadasan Pillai, Harikrishnan; Ganapathi, Sanjay
South Asia (SA) is both the most populous and the most densely populated geographical region in the world. The countries in this region are undergoing epidemiological transition and are facing the double burden of infectious and non-communicable diseases. Heart failure (HF) is a major and increasing burden all over the world. In this review, we discuss the epidemiology of HF in SA today and its impact in the health system of the countries in the region. There are no reliable estimates of incidence and prevalence of HF (heart failure) from this region. The prevalence of HF which is predominantly a disease of the elderly is likely to rise in this region due to the growing age of the population. Patients admitted with HF in the SA region are relatively younger than their western counterparts. The etiology of HF in this region is also different from the western world. Untreated congenital heart disease and rheumatic heart disease still contribute significantly to the burden of HF in this region. Due to epidemiological transition, the prevalence of hypertension, diabetes mellitus, obesity and smoking is on the rise in this region. This is likely to escalate the prevalence of HF in South Asia. We also discuss potential developments in the field of HF management likely to occur in the nations in South Asia. Finally, we discuss the interventions for prevention of HF in this region PMID:23597297
Spin-orbit interaction driven collective electron-hole excitations in a noncentrosymmetric nodal loop Weyl semimetal
NASA Astrophysics Data System (ADS)
Ahn, Kyo-Hoon; Lee, Kwan-Woo; Pickett, Warren E.
NbP is one member of a new class of nodal loop semimetals characterized by the cooperative effects of spin-orbit coupling (SOC) and a lack of inversion center. Here transport and spectroscopic properties of NbP are evaluated using density functional theory methods. SOC together with the lack of inversion symmetry splits degeneracies, giving rise to "Russian doll nested" Fermi surfaces containing 4 ×10-4 electron (hole) carriers/f.u. Due to the modest SOC strength in Nb, the Fermi surfaces map out the Weyl nodal loops. Calculated structure around T*≈100 K in transport properties reproduces well the observed transport behavior only when SOC is included, attesting to the precision of the (delicate) calculations and the stoichiometry of the samples. Low-energy collective electron-hole excitations (plasmons) in the 20-60 meV range result from the nodal loop splitting.
Shifting nodal-plane suppressions in high-order-harmonic spectra from diatomic molecules in orthogonally polarized driving fields
NASA Astrophysics Data System (ADS)
Das, T.; Figueira de Morisson Faria, C.
We analyze the imprint of nodal planes in high-order-harmonic spectra from aligned diatomic molecules in intense laser fields whose components exhibit orthogonal polarizations. We show that the typical suppression in the spectra associated to nodal planes is distorted, and that this distortion can be employed to map the electron's angle of return to its parent ion. This investigation is performed semianalytically at the single-molecule response and single-active orbital level, using the strong-field approximation and the steepest descent method. We show that the velocity form of the dipole operator is superior to the length form in providing information about this distortion. However, both forms introduce artifacts that are absent in the actual momentum-space wave function. Furthermore, elliptically polarized fields lead to larger distortions in comparison to two-color orthogonally polarized fields. These features are investigated in detail for O2, whose highest occupied molecular orbital provides two orthogonal nodal planes.
Development of a standing-wave fluorescence microscope with high nodal plane flatness.
Freimann, R; Pentz, S; Hörler, H
This article reports about the development and application of a standing-wave fluorescence microscope (SWFM) with high nodal plane flatness. As opposed to the uniform excitation field in conventional fluorescence microscopes as SWFM uses a standing-wave pattern of laser light. This pattern consists of alternating planar nodes and antinodes. By shifting it along the axis of the microscope a set of different fluorescent structures can be distinguished. Their axial separation may just be a fraction of a wavelength so that an SWFM allows distinction of structures which would appear axially unresolved in a conventional or confocal fluorescence microscope. An SWFM is most powerful when the axial extension of the specimen is comparable to the wavelength of light. Otherwise several planes are illuminated simultaneously and their separation is hardly feasible. The objective of this work was to develop a new SWFM instrument which allows standing-wave fluorescence microscopy with controlled high nodal plane flatness. Earlier SWFMs did not allow such a controlled flatness, which impeded image interpretation and processing. Another design goal was to build a compact, easy-to-use instrument to foster a more widespread use of this new technique. The instrument developed uses a green-emitting helium-neon laser as the light source, a piezoelectric movable beamsplitter to generate two mutually coherent laser beams of variable relative phase and two single-mode fibres to transmit these beams to the microscope. Each beam is passed on to the specimen by a planoconvex lens and an objective lens. The only reflective surface whose residual curvature could cause wavefront deformations is a dichroic beamsplitter. Nodal plane flatness is controlled via interference fringes by a procedure which is similar to the interferometric test of optical surfaces. The performance of the instrument was tested using dried and fluorescently labelled cardiac muscle cells of rats. The SWFM enabled the
Atlas-Based Segmentation Improves Consistency and Decreases Time Required for Contouring Postoperative Endometrial Cancer Nodal Volumes
Young, Amy V.; Wortham, Angela; Wernick, Iddo; Evans, Andrew; Ennis, Ronald D.
Purpose: Accurate target delineation of the nodal volumes is essential for three-dimensional conformal and intensity-modulated radiotherapy planning for endometrial cancer adjuvant therapy. We hypothesized that atlas-based segmentation ('autocontouring') would lead to time savings and more consistent contours among physicians. Methods and Materials: A reference anatomy atlas was constructed using the data from 15 postoperative endometrial cancer patients by contouring the pelvic nodal clinical target volume on the simulation computed tomography scan according to the Radiation Therapy Oncology Group 0418 trial using commercially available software. On the simulation computed tomography scans from 10 additional endometrial cancer patients, the nodal clinical target volume autocontours were generated. Three radiation oncologists corrected the autocontours and delineated the manual nodal contours under timed conditions while unaware of the other contours. The time difference was determined, and the overlap of the contours was calculated using Dice's coefficient. Results: For all physicians, manual contouring of the pelvic nodal target volumes and editing the autocontours required a mean {+-} standard deviation of 32 {+-} 9 vs. 23 {+-} 7 minutes, respectively (p = .000001), a 26% time savings. For each physician, the time required to delineate the manual contours vs. correcting the autocontours was 30 {+-} 3 vs. 21 {+-} 5 min (p = .003), 39 {+-} 12 vs. 30 {+-} 5 min (p = .055), and 29 {+-} 5 vs. 20 {+-} 5 min (p = .0002). The mean overlap increased from manual contouring (0.77) to correcting the autocontours (0.79; p = .038). Conclusion: The results of our study have shown that autocontouring leads to increased consistency and time savings when contouring the nodal target volumes for adjuvant treatment of endometrial cancer, although the autocontours still required careful editing to ensure that the lymph nodes at risk of recurrence are properly included in the target
"Nodal Gap" induced by the incommensurate diagonal spin density modulation in underdoped high- Tc superconductors
Zhou, Tao; Gao, Yi; Zhu, Jian -Xin
Recenmore » tly it was revealed that the whole Fermi surface is fully gapped for several families of underdoped cuprates. The existence of the finite energy gap along the d-wave nodal lines (nodal gap) contrasts the common understanding of the d-wave pairing symmetry, which challenges the present theories for the high-Tcsuperconductors. Here we propose that the incommensurate diagonal spin-density-wave order can account for the above experimental observation. The Fermi surface and the local density of states are also studied. Our results are in good agreement with many important experiments in high-Tcsuperconductors.« less
Performance of a recoverable tug for planetary missions including use of perigee propulsion and corrections for nodal regression
NASA Technical Reports Server (NTRS)
Borsody, J.
Mathematical equations are derived by using the Maximum Principle to obtain the maximum payload capability of a reusable tug for planetary missions. The mathematical formulation includes correction for nodal precession of the space shuttle orbit. The tug performs this nodal correction in returning to this precessed orbit. The sample case analyzed represents an inner planet mission as defined by the declination (fixed) and right ascension of the outgoing asymptote and the mission energy. Payload capability is derived for a typical cryogenic tug and the sample case with and without perigee propulsion. Optimal trajectory profiles and some important orbital elements are also discussed.
... Artery Disease Venous Thromboembolism Aortic Aneurysm More Advanced Heart Failure Updated:Feb 9,2017 When heart failure (HF) ... content was last reviewed on 04/06/2015. Heart Failure • Home • About Heart Failure • Causes and Risks for ...
A unique microRNA profile in end-stage heart failure indicates alterations in specific cardiovascular signaling networks
Duan, Zhong-Hui; Surampudi, Venkata Suresh K.; Liu, Chang-Gong; Kotwal, Ashwin; Moravec, Christine S.; Starling, Randall C.; Perez, Dianne M.; Sen, Subha; Wu, Qingyu; Plow, Edward F.; Karnik, Sadashiva
It is well established that the gene expression patterns are substantially altered in cardiac hypertrophy and heart failure, however, less is known about the reasons behind such global differences. MicroRNAs (miRNAs) are short non-coding RNAs that can target multiple molecules to regulate wide array of proteins in diverse pathways. The goal of the study was to profile alterations in miRNA expression using end-stage human heart failure samples with an aim to build signaling network pathways using predicted targets for the altered miRNA and to determine nodal molecules regulating individual networks. Profiling of miRNAs using custom designed microarray and validation with an independent set of samples identified eight miRNAs that are altered in human heart failure including one novel miRNA yet to be implicated in cardiac pathology. To gain an unbiased perspective on global regulation by top eight altered miRNAs, functional relationship of predicted targets for these eight miRNAs were examined by network analysis. Ingenuity Pathways Analysis network algorithm was used to build global signaling networks based on the targets of altered miRNAs which allowed us to identify participating networks and nodal molecules that could contribute to cardiac pathophysiology. Majority of the nodal molecules identified in our analysis are targets of altered miRNAs and known regulators of cardiovascular signaling. Cardio-genomics heart failure gene expression public data base was used to analyze trends in expression pattern for target nodal molecules and indeed changes in expression of nodal molecules inversely correlated to miRNA alterations. We have used NF kappa B network as an example to show that targeting other molecules in the network could alter the nodal NF kappa B despite not being a miRNA target suggesting an integrated network response. Thus, using network analysis we show that altering key functional target proteins may regulate expression of the myriad signaling pathways
Salvage reirradiation for locoregional failure after radiation therapy for prostate cancer: who, when, where and how?
Créhange, G; Roach, M; Martin, E; Cormier, L; Peiffert, D; Cochet, A; Chapet, O; Supiot, S; Cosset, J-M; Bolla, M; Chung, H T
Even in the current era of dose-escalated radiotherapy for prostate cancer, biochemical recurrence is not uncommon. Furthermore, biochemical failure is not specific to the site of recurrence. One of the major challenges in the management of prostate cancer patients with biochemical failure after radiotherapy is the early discrimination between those with locoregional recurrence only and those with metastatic disease. While the latter are generally considered incurable, patients with locoregional disease may benefit from emerging treatment options. Ultimately, the objective of salvage therapy is to control disease while ensuring minimal collateral damage, thereby optimizing both cancer and toxicity outcomes. Advances in functional imaging, including multiparametric prostate MRI, abdominopelvic lymphangio-MRI, sentinel node SPECT-CT and/or whole-body PET/CT have paved the way for salvage radiotherapy in patients with local recurrence, microscopic nodal disease limited to the pelvis or oligometastatic disease. These patients may be considered for salvage reirradiation using different techniques: prostate low-dose or high-dose rate brachytherapy, pelvic and/or lomboaortic image-guided radiotherapy with elective nodal irradiation, focal nodal or bone stereotactic body radiation therapy (SBRT). An individualized approach is recommended. The decision about which treatment, if any, to use will be based on the initial characteristics of the disease, relapse patterns and the natural history of the rising prostate specific antigen (PSA). Preliminary results suggest that more than 50% of patients who have undergone salvage reirradiation are biochemically relapse-free with very low rates of severe toxicity. Large prospective studies with a longer follow-up are needed to confirm the promising benefit/risk ratio observed with salvage brachytherapy and or salvage nodal radiotherapy and/or bone oligometastatic SBRT when compared with life-long palliative hormones.
The Beni-Ilmène earthquake sequence (Mw=5.5, 5.3, and 5.3) from 14 to 23 May, 2010, in the Biban region (Mansourah, Algeria): determination of sources parameters and stress transfer
NASA Astrophysics Data System (ADS)
Beldjoudi, Hamoud; Djellit, Hamou; Delouis, Bertrand; Yelles-Chaouche, Abdelkrim; Gharbi, Sofiane
A moderate earthquake with moment magnitude Mw=5.5 (first shock) hit the Subbibanique region in the East of Algeria at the locality of Beni-Ilmène (NW of Msila) on 14 May, 2010 at 12h29mn (GMT). The earthquake was located by the CRAAG at latitude 35.99° N and longitude 4.19° E, the depth was 6 km. Three persons were killed, hundred injured and huge damages were observed in the epicentral area (Béni-Ilmène, Samma, Bendaoud, Ounougha). The Focal Mechanism (FM) of the seismic source obtained by waveform modeling (near-field) shows left-lateral strike-slip for the nodal plane oriented N345° and right-lateral strike-slip for the second nodal plane oriented N254°. A second shock stroke the region on 16 May 2010 at 06h52mn (GMT) with moment magnitude Mw=5.3. It is localized 9 km SW of the first shock at latitude 35.96° N, longitude 4.06° E and 5 km of depth. The FM obtained by waveform modeling shows reverse faulting with nodal planes oriented NE-SW. A third shock hit the region on 23 may 2010 at 13h28 (GMT) with moment magnitude Mw=5.3, localized 7 km at the south of the first shock at the latitude 35.93° N, longitude 4.12° N and 6 km of depth. The FM obtained shows a left-lateral strike-slip plane oriented N355° and a right-lateral plane oriented N85° similar to that of the first shock. Field investigations, geologic and sismotectonic analysis lead us to conclude that the fault plane of the first shock is oriented NNW-SSE, i.e corresponding to the nodal plane [strike, Dip, Rake: 345°, 85°, 16°]. The second and the third shocks were generated by separate faults [strike, Dip, rake: 250°, 55°, 120°] and [Strike, Dip, rake: 355°, 90°,-12°] respectively. We show that the first shock raised the Coulomb Stress Failure level on the fault planes that generated the two following shocks of Mw 5.3.
Structural system reliability under multiple failure modes
NASA Technical Reports Server (NTRS)
Mahadevan, S.; Chamis, C. C.
This paper describes a computational method for system reliability estimation of propulsion structures. The failure domain of the entire structural system is computed through the union of failure regions for various critical system failure modes. The effect of non-critical progressive damage is incorporated through structural reanalysis, resulting in the construction of several linear segments to approximately cover the system failure domain. An adaptive damage imposition scheme is outlined for the sake of computational efficiency. The proposed method is used to construct the system survival cdf (cumulative distribution function) of a two-rotor system.
Numerical Solution of Poroelastic Wave Equation Using Nodal Discontinuous Galerkin Finite Element Method
NASA Astrophysics Data System (ADS)
Shukla, K.; Wang, Y.; Jaiswal, P.
In a porous medium the seismic energy not only propagates through matrix but also through pore-fluids. The differential movement between sediment grains of the matrix and interstitial fluid generates a diffusive wave which is commonly referred to as the slow P-wave. A combined system of equation which includes both elastic and diffusive phases is known as the poroelasticity. Analyzing seismic data through poroelastic modeling results in accurate interpretation of amplitude and separation of wave modes, leading to more accurate estimation of geomehanical properties of rocks. Despite its obvious multi-scale application, from sedimentary reservoir characterization to deep-earth fractured crust, poroelasticity remains under-developed primarily due to the complex nature of its constituent equations. We present a detail formulation of poroleastic wave equations for isotropic media by combining the Biot's and Newtonian mechanics. System of poroelastic wave equation constitutes for eight time dependent hyperbolic PDEs in 2D whereas in case of 3D number goes up to thirteen. Eigen decomposition of Jacobian of these systems confirms the presence of an additional slow-P wave phase with velocity lower than shear wave, posing stability issues on numerical scheme. To circumvent the issue, we derived a numerical scheme using nodal discontinuous Galerkin approach by adopting the triangular meshes in 2D which is extended to tetrahedral for 3D problems. In our nodal DG approach the basis function over a triangular element is interpolated using Legendre-Gauss-Lobatto (LGL) function leading to a more accurate local solutions than in the case of simple DG. We have tested the numerical scheme for poroelastic media in 1D and 2D case, and solution obtained for the systems offers high accuracy in results over other methods such as finite difference , finite volume and pseudo-spectral. The nodal nature of our approach makes it easy to convert the application into a multi-threaded algorithm
Progressive leukemic non-nodal mantle cell lymphoma associated with deletions of TP53, ATM, and/or 13q14.
Chapman-Fredricks, Jennifer; Sandoval-Sus, Jose; Vega, Francisco; Lossos, Izidore S
Leukemic, non-nodal mantle cell lymphoma (MCL) is a relatively indolent disease characterized by asymptomatic leukemic presentation, non-nodal disease distribution, and slow disease progression, particularly in comparison to that of classic nodal MCL. We studied 3 cases of leukemic, non-nodal MCL in which TP53, ATM, and/or 13q14 deletions were identified. All three patients had disease progression leading to treatment requirements in two of the patients at 5 and 18 months after initial diagnosis. The third patient also clinically progressed 25 months after initial diagnosis but was lost to follow up despite recommendation for initiation of therapy. We present these cases as potential evidence that while leukemic non-nodal MCL is typically an indolent disease compared to classically defined mantle cell lymphoma, cytogenetic heterogeneity exists and cases with TP53, ATM, and/or 13q14 deletions may have a relatively aggressive clinical course.
Clinicopathologic and molecular features of 122 Brazilian cases of nodal and extranodal NK/T-cell lymphoma, nasal type, with EBV subtyping analysis.
Gualco, Gabriela; Domeny-Duarte, Pollyanna; Chioato, Lucimara; Barber, Glen; Natkunam, Yasodha; Bacchi, Carlos E
Extranodal natural killer/T-cell lymphoma, nasal type (NK/TCL) is more prevalent in Asia and in some areas of South and Central America, but it is rarely seen in the United States and Europe. In this study, a series of 122 cases of NK/TCL from Brazil was analyzed with respect to clinicopathologic features. Clinical characteristics and geographic distribution were evaluated in 97 cases of nasal/nasopharyngeal region and 23 cases in extranasal sites including 6 nodal cases. Clinical staging and follow-up information was available in a subset of 21 patients. All cases harbored Epstein-Barr virus (EBV), 95% and 85% expressed cytoplasmic CD3 and CD56, respectively, and all cases were positive for at least 1 marker for cytotoxic granules. The global distribution of EBV subtypes showed predominance of strain subtype A, 89%, and subtype B, 11%. No dual infections were detected. TCR-γ TCR-gene rearrangement was observed in 7 cases; all of them extranodal. Three of TCR-γ(+) cases showed EBV subtype A. Two TCR-γ(+)/CD56(+) cases showed EBV subtype B. Geographic distribution of NK/TCL showed higher frequency in the southeast and northeast regions of Brazil. Striking differences among geographic regions were seen with the vast majority of EBV subtype B (86%) occurring in the south and southeast regions.
Nodal Network Modelling by Integrating Remote Sensing Derived Actual Evapotranspiration with Spatial Water Balance in a Demand Driven Irrigation System
NASA Astrophysics Data System (ADS)
Ullah, Kaleem; Hafeez, Mohsin; Sixsmith, Josh; Faux, Ralph
The long-term sustainability of water for agriculture is in doubt in many regions of the world. The major withdrawals of water are for agriculture, industry, and domestic consumption. Irrigated agriculture is major consumer of fresh water, but a large part of the water devour for irrigation is wasted due to poor management of irrigation systems. Improving water management in irrigated areas and assessment of irrigation performance are critical activities for this endeavour. These activities are needed not only to improve water productivity, but also to increase the sustainability of irrigated agriculture and improving the irrigation efficiency. The improvement of the water use efficiency entail the complete understanding of various components of water balances such as rainfall, surface water, groundwater and evapotranspiration (ET). Evapotranspiration is the overriding aspect of water balance at farm to catchment scale. Many models have been used to measure the Evapotranspiration rate, either empirical or functional. The major disadvantage of this approach is that most methods generate only point values, resulting in estimates that are not representative of large areas. These methods are based on crop factors under ideal conditions and cannot therefore represent actual crop ET. Satellite remote sensing is a powerful mean to estimate ET over various spatial and temporal scales. The use of remote sensing techniques to estimate ET is achieved by solving the energy balance thermodynamics fluxes at the surface of the earth. For improved irrigation system management and operation, a holistic approach of integrating remote sensing derived ET from SAM-ET (spatial algorithm for mapping evapotranspiration) algorithm, for Australian agro-ecosystem with spatial water balance by using nodal network model was applied to evaluate agricultural water management in Coleambally Irrigation Area (CIA), New South Wales, Australia. It covers approximately 79,000 ha of intensive
Probing the Nodal Structure of Landau Level Wave Functions in Real Space.
Bindel, J R; Ulrich, J; Liebmann, M; Morgenstern, M
The inversion layer of p-InSb(110) obtained by Cs adsorption of 1.8% of a monolayer is used to probe the Landau level wave functions within smooth potential valleys by scanning tunneling spectroscopy at 14 T. The nodal structure becomes apparent as a double peak structure of each spin polarized first Landau level, while the zeroth Landau level exhibits a single peak per spin level only. The real space data show single rings of the valley-confined drift states for the zeroth Landau level and double rings for the first Landau level. The result is reproduced by a recursive Green function algorithm using the potential landscape obtained experimentally. We show that the result is generic by comparing the local density of states from the Green function algorithm with results from a well-controlled analytic model based on the guiding center approach.
Response to Nodal morphogen gradient is determined by the kinetics of target gene induction
Dubrulle, Julien; Jordan, Benjamin M; Akhmetova, Laila; Farrell, Jeffrey A; Kim, Seok-Hyung; Solnica-Krezel, Lilianna; Schier, Alexander F
Morphogen gradients expose cells to different signal concentrations and induce target genes with different ranges of expression. To determine how the Nodal morphogen gradient induces distinct gene expression patterns during zebrafish embryogenesis, we measured the activation dynamics of the signal transducer Smad2 and the expression kinetics of long- and short-range target genes. We found that threshold models based on ligand concentration are insufficient to predict the response of target genes. Instead, morphogen interpretation is shaped by the kinetics of target gene induction: the higher the rate of transcription and the earlier the onset of induction, the greater the spatial range of expression. Thus, the timing and magnitude of target gene expression can be used to modulate the range of expression and diversify the response to morphogen gradients. DOI: http://dx.doi.org/10.7554/eLife.05042.001 PMID:25869585
Majorana fermions in spin-singlet nodal superconductors with coexisting non-collinear magnetic order
NASA Astrophysics Data System (ADS)
Wang, Ziqiang; Lu, Yuan-Ming
Realizations of Majorana fermions in solid state materials have attracted great interests recently in connection to topological order and quantum information processing. We propose a novel way to create Majorana fermions in superconductors. We show that an incipient non-collinear magnetic order turns a spin-singlet superconductor with nodes into a topological superconductor with a stable Majorana bound state (MBS) in the vortex core or on the edge. Moreover the topologically-stable point defect of non-collinear magnetic order also hosts a zero-energy MBS. We argue that such an exotic non-Abelian phase can be realized in extended t- J models on the triangular and square lattices. Our proposal suggests a new avenue for the search of Majorana fermions in correlated electron materials where nodal superconductivity and magnetism are two common caricatures.
Probing the Nodal Structure of Landau Level Wave Functions in Real Space
NASA Astrophysics Data System (ADS)
Bindel, J. R.; Ulrich, J.; Liebmann, M.; Morgenstern, M.
The inversion layer of p -InSb (110 ) obtained by Cs adsorption of 1.8% of a monolayer is used to probe the Landau level wave functions within smooth potential valleys by scanning tunneling spectroscopy at 14 T. The nodal structure becomes apparent as a double peak structure of each spin polarized first Landau level, while the zeroth Landau level exhibits a single peak per spin level only. The real space data show single rings of the valley-confined drift states for the zeroth Landau level and double rings for the first Landau level. The result is reproduced by a recursive Green function algorithm using the potential landscape obtained experimentally. We show that the result is generic by comparing the local density of states from the Green function algorithm with results from a well-controlled analytic model based on the guiding center approach.
Pseudodiffusive transmission of nodal Dirac fermions through a clean d -wave superconductor
NASA Astrophysics Data System (ADS)
Asbóth, J. K.; Akhmerov, A. R.; Berceanu, A. C.; Beenakker, C. W. J.
We calculate the transmission of electrons and holes between two normal-metal (N) electrodes, separated over a distance L by an impurity-free superconductor (S) with d -wave symmetry of the order parameter. Nodal lines of vanishing excitation gap form ballistic conduction channels for coupled electron-hole excitations, described by an anisotropic two-dimensional Dirac equation. We find that the transmitted electrical and thermal currents both have the pseudodiffusive 1/L scaling characteristic of massless Dirac fermions—regardless of the presence of tunnel barriers at the NS interfaces. Tunnel barriers reduce the slope of the 1/L scaling in the case of the electrical current while leaving the thermal current unaffected.
Quantum criticality and nodal superconductivity in the FeAs-based superconductor KFe2As2.
Dong, J K; Zhou, S Y; Guan, T Y; Zhang, H; Dai, Y F; Qiu, X; Wang, X F; He, Y; Chen, X H; Li, S Y
The in-plane resistivity rho and thermal conductivity kappa of the FeAs-based superconductor KFe2As2 single crystal were measured down to 50 mK. We observe non-Fermi-liquid behavior rho(T) approximately T{1.5} at H{c{2}}=5 T, and the development of a Fermi liquid state with rho(T) approximately T{2} when further increasing the field. This suggests a field-induced quantum critical point, occurring at the superconducting upper critical field H{c{2}}. In zero field, there is a large residual linear term kappa{0}/T, and the field dependence of kappa_{0}/T mimics that in d-wave cuprate superconductors. This indicates that the superconducting gaps in KFe2As2 have nodes, likely d-wave symmetry. Such a nodal superconductivity is attributed to the antiferromagnetic spin fluctuations near the quantum critical point.
High critical temperature nodal superconductors as building block for time-reversal invariant topological superconductivity
NASA Astrophysics Data System (ADS)
Trani, F.; Campagnano, G.; Tagliacozzo, A.; Lucignano, P.
We study possible applications of high critical temperature nodal superconductors for the search for Majorana bound states in the DIII class. We propose a microscopic analysis of the proximity effect induced by d -wave superconductors on a semiconductor wire with strong spin-orbit coupling. We characterize the induced superconductivity on the wire employing a numerical self-consistent tight-binding Bogoliubov-de Gennes approach, and analytical considerations on the Green's function. The order parameter induced on the wire, the pair correlation function, and the renormalization of the Fermi points are analyzed in detail, as well as the topological phase diagram in the case of weak coupling. We highlight optimal Hamiltonian parameters to access the nontrivial topological phase which could display time-reversal invariant Majorana doublets at the boundaries of the wire.
A study of the radiative transfer equation using a spherical harmonics-nodal collocation method
NASA Astrophysics Data System (ADS)
Capilla, M. T.; Talavera, C. F.; Ginestar, D.; Verdú, G.
Optical tomography has found many medical applications that need to know how the photons interact with the different tissues. The majority of the photon transport simulations are done using the diffusion approximation, but this approximation has a limited validity when optical properties of the different tissues present large gradients, when structures near the photons source are studied or when anisotropic scattering has to be taken into account. As an alternative to the diffusion model, the PL equations for the radiative transfer problem are studied. These equations are discretized in a rectangular mesh using a nodal collocation method. The performance of this model is studied by solving different 1D and 2D benchmark problems of light propagation in tissue having media with isotropic and anisotropic scattering.
Field-induced reentrant superconductivity in thin films of nodal superconductors
NASA Astrophysics Data System (ADS)
Hachiya, M.; Aoyama, K.; Ikeda, R.
Previous work on nodal d-wave superconductors has shown that a Fulde-Ferrell-Larkin-Ovchinnikov- (FFLO-) like superconducting (SC) state, which is modulated along the film plane, can be realized with no magnetic field when quasiparticles acquire an additional linear term in the wave vector in their dispersion. In the present work, the stability of such a modulated SC state in an artificial film against an applied magnetic field is studied. As a reflection of the presence of two FFLO-like states of different origins, one close to zero field and the other at the high-field end, in a single field vs temperature phase diagram of thin films, the conventional SC state, which is uniform along the film plane, generally tends to appear as a reentrant ordered phase bounded by the normal phase in lower fields.
Lunar nodal tide and distance to the moon during the Precambrian
NASA Technical Reports Server (NTRS)
Walker, J. C. G.; Zahnle, K. J.
The first direct determination of the lunar distance in the Precambrian is presented. A 23.3 + or - 0.3 yr periodicity preserved in 2500 Myr BP Australian banded iron formation is interpreted as reflecting the climatic influence of the lunar nodal tide, which has been detected with its modern 18.6-yr periodicity in some modern climate records. The lunar distance at 2500 Myr BP would then have been about 52 earth radii. The implied history of precambrian tidal friction is in accord with both the more recent paleontological evidence and the long-term stability of the lunar orbit. The length of the Milankovitch cycles that modulate the ice ages today also evolve with the earth-moon system. Their detection in the Precambrian sedimentary record would then permit an independent determination of the lunar distance.
Nodal Structure of Quasi-Two-Dimensional Superconductors Probed by a Magnetic Field
NASA Astrophysics Data System (ADS)
Vorontsov, A.; Vekhter, I.
We consider a quasi-two-dimensional superconductor with line nodes in the presence of an in-plane magnetic field, and compute the dependence of the specific heat C and the in-plane heat conductivity κ on the angle between the field and the nodal direction in the vortex state. We use a variation of the microscopic Brandt-Pesch-Tewordt method that accounts for the scattering of quasiparticles off vortices, and analyze the signature of the nodes in C and κ. At low to moderate fields the specific heat anisotropy changes sign with increasing temperature. Comparison with measurements of C and κ in CeCoIn5 resolves the contradiction between the two in favor of the dx2-y2 gap.
Diagnosis of non-nodal paratracheobronchial lesions by linear endobronchial ultrasound.
Lourido, Tamara; Botana, Maribel; Leiro, Virginia; Núñez, Manuel; Fernández-Villar, Alberto
Linear endobronchial ultrasound (EBUS) allows samples of lesions close to the airways to be obtained, as it enables aspiration to be performed under visual control in real time, opening new possibilities for minimally invasive examination of the mediastinum. While there are many publications on its usefulness in the study of mediastinal or hilar lymphadenopathies, there are few that analyse the role of EBUS-guided transbronchial needle aspiration for the diagnosis of other lesions adjacent to the airways or digestive tract. We describe the characteristics and results obtained in a series of 26 cases of non-nodal lesions of different aetiologies studied by EBUS- guided transbronchial needle aspiration through the airways or oesophagus, demonstrating the usefulness and safety of this technique in the diagnosis of these types of lesions.
The HOMO Nodal Arrangement in Polychromophoric Molecules and Assemblies Controls the Interchromophoric Electronic Coupling.
Talipov, Marat R; Navale, Tushar S; Rathore, Rajendra
Triptycenes spontaneously assemble into two-dimensional networks in which long-range charge transport is facilitated by the extensive electronic coupling through the triptycene framework (intramolecularly) and by cofacial π-stacking (intermolecularly). While designing and synthesizing next-generation triptycenes containing polyaromatic chromophores, the electronic coupling amongst the chromophores was observed to be highly dependent on the nature and position of the substituents. Herein, we demonstrate using hexaalkoxytriptycenes that the electronic coupling amongst the chromophores is switched on and off by a simple repositioning of the substituents, which alters the nodal arrangement of the HOMOs of the individual chromophores. A visual inspection of the HOMOs can thus provide a ready evaluation of the electronic coupling in polychromophoric molecules/assemblies, and will serve as an important tool for the rational design of modern charge-transport materials.
NODAL secreted by male germ cells regulates the proliferation and function of human Sertoli cells from obstructive azoospermia and nonobstructive azoospermia patients
Tian, Ru-Hui; Yang, Shi; Zhu, Zi-Jue; Wang, Jun-Long; Liu, Yun; Yao, Chencheng; Ma, Meng; Guo, Ying; Yuan, Qingqing; Hai, Yanan; Huang, Yi-Ran; He, Zuping; Li, Zheng
This study was designed to explore the regulatory effects of male germ cell secreting factor NODAL on Sertoli cell fate decisions from obstructive azoospermia (OA) and nonobstructive azoospermia (NOA) patients. Human Sertoli cells and male germ cells were isolated using two-step enzymatic digestion and SATPUT from testes of azoospermia patients. Expression of NODAL and its multiple receptors in human Sertoli cells and male germ cells were characterized by reverse transcription-polymerase chain reaction (RT-PCR) and immunochemistry. Human recombinant NODAL and its receptor inhibitor SB431542 were employed to probe their effect on the proliferation of Sertoli cells using the CCK-8 assay. Quantitative PCR and Western blots were utilized to assess the expression of Sertoli cell functional genes and proteins. NODAL was found to be expressed in male germ cells but not in Sertoli cells, whereas its receptors ALK4, ALK7, and ACTR-IIB were detected in Sertoli cells and germ cells, suggesting that NODAL plays a regulatory role in Sertoli cells and germ cells via a paracrine and autocrine pathway, respectively. Human recombinant NODAL could promote the proliferation of human Sertoli cells. The expression of cell cycle regulators, including CYCLIN A, CYCLIN D1 and CYCLIN E, was not remarkably affected by NODAL signaling. NODAL enhanced the expression of essential growth factors, including GDNF, SCF, and BMP4, whereas SB431542 decreased their levels. There was not homogeneity of genes changes by NODAL treatment in Sertoli cells from OA and Sertoli cell-only syndrome (SCO) patients. Collectively, this study demonstrates that NODAL produced by human male germ cells regulates proliferation and numerous gene expression of Sertoli cells. PMID:26289399
Theory of nodal s±-wave pairing symmetry in the Pu-based 115 superconductor family
Das, Tanmoy; Zhu, Jian -Xin; Graf, Matthias J.
The spin-fluctuation mechanism of superconductivity usually results in the presence of gapless or nodal quasiparticle states in the excitation spectrum. Nodal quasiparticle states are well established in copper-oxide, and heavy-fermion superconductors, but not in iron-based superconductors. Here, we study the pairing symmetry and mechanism of a new class of plutonium-based high-Tc superconductors and predict the presence of a nodal s⁺⁻ wave pairing symmetry in this family. Starting from a density-functional theory (DFT) based electronic structure calculation we predict several three-dimensional (3D) Fermi surfaces in this 115 superconductor family. We identify the dominant Fermi surface "hot-spots" in the inter-band scattering channel, which are aligned along the wavevector Q = (π, π, π), where degeneracy could induce sign-reversal of the pairing symmetry. Our calculation demonstrates that the s⁺⁻ wave pairing strength is stronger than the previously thought d-wave pairing; and more importantly, this pairing state allows for the existence of nodal quasiparticles. Finally, we predict the shape of the momentum- and energy-dependent magnetic resonance spectrum for the identification of this pairing symmetry.
Theory of nodal s±-wave pairing symmetry in the Pu-based 115 superconductor family
Das, Tanmoy; Zhu, Jian -Xin; Graf, Matthias J.
The spin-fluctuation mechanism of superconductivity usually results in the presence of gapless or nodal quasiparticle states in the excitation spectrum. Nodal quasiparticle states are well established in copper-oxide, and heavy-fermion superconductors, but not in iron-based superconductors. Here, we study the pairing symmetry and mechanism of a new class of plutonium-based high-Tc superconductors and predict the presence of a nodal s⁺⁻ wave pairing symmetry in this family. Starting from a density-functional theory (DFT) based electronic structure calculation we predict several three-dimensional (3D) Fermi surfaces in this 115 superconductor family. We identify the dominant Fermi surface "hot-spots" in the inter-band scattering channel,more » which are aligned along the wavevector Q = (π, π, π), where degeneracy could induce sign-reversal of the pairing symmetry. Our calculation demonstrates that the s⁺⁻ wave pairing strength is stronger than the previously thought d-wave pairing; and more importantly, this pairing state allows for the existence of nodal quasiparticles. Finally, we predict the shape of the momentum- and energy-dependent magnetic resonance spectrum for the identification of this pairing symmetry.« less
Identification and expression of Smads associated with TGF-beta/activin/nodal signaling pathways in the rainbow trout (Oncorhynuchus mykiss)
Technology Transfer Automated Retrieval System (TEKTRAN)
The Smad proteins are essential components of the TGF-beta/activin/nodal family signaling pathway. We report the identification and characterization of transcripts representing 3 receptor Smads (Smad2a, Smad2b, Smad3), 2 common Smads (Smad4a, Smad4b) and one inhibitory Smad (Smad7). Phylogenetic an...
Theory of nodal s±-wave pairing symmetry in the Pu-based 115 superconductor family
Das, Tanmoy; Zhu, Jian-Xin; Graf, Matthias J.
The spin-fluctuation mechanism of superconductivity usually results in the presence of gapless or nodal quasiparticle states in the excitation spectrum. Nodal quasiparticle states are well established in copper-oxide, and heavy-fermion superconductors, but not in iron-based superconductors. Here, we study the pairing symmetry and mechanism of a new class of plutonium-based high-Tc superconductors and predict the presence of a nodal s+− wave pairing symmetry in this family. Starting from a density-functional theory (DFT) based electronic structure calculation we predict several three-dimensional (3D) Fermi surfaces in this 115 superconductor family. We identify the dominant Fermi surface "hot-spots" in the inter-band scattering channel, which are aligned along the wavevector Q = (π, π, π), where degeneracy could induce sign-reversal of the pairing symmetry. Our calculation demonstrates that the s+− wave pairing strength is stronger than the previously thought d-wave pairing; and more importantly, this pairing state allows for the existence of nodal quasiparticles. Finally, we predict the shape of the momentum- and energy-dependent magnetic resonance spectrum for the identification of this pairing symmetry. PMID:25721375
Acute effects of simvastatin to terminate fast reentrant tachycardia through increasing wavelength of atrioventricular nodal reentrant tachycardia circuit.
Khori, Vahid; Alizadeh, Ali Mohammad; Moheimani, Hamid Reza; Zahedi, Mahdi; Aminolsharieh Najafi, Soroosh; Shakiba, Delaram; Nayebpour, Mohsen
Simvastatin (SV) leads to reduction of ventricular rhythm during atrial fibrillation on rabbit atrioventricular (AV) nodes. The aim of our study was (i) to determine the frequency-dependent effects of SV in a functional model, and (ii) to assess the effects of SV to suppress experimental AV nodal reentrant tachycardia (AVNRT). Selective stimulation protocols were used with two different pacing protocols, His to atrial, and atrial to atrial (AA). An experimental AVNRT model with various cycle lengths was created in three groups of perfused rabbit AV nodal preparations (n = 24) including: SV 3 μm, SV 7 μm, and verapamil 0.1 μm. SV increased nodal conduction time and refractoriness by AA pacing. Different simulated models of slow/fast and fast/slow reentry were induced. SV caused inhibitory effects on the slow anterograde conduction (origin of refractoriness) more than on the fast anterograde conduction time, leading to an increase of tachycardia cycle length, tachycardia wavelength and termination of slow/fast reentrant tachyarrhythmia. Verapamil significantly suppressed the basic and frequency-dependent intrinsic nodal properties. In addition, SV decreased the incidence of gap and echo beats. The present study showed that SV in a concentration and rate-dependent manner increased the AV effective refractory period and reentrant tachycardia wavelength that lead to slowing or termination of experimental fast AVNRT. The direction-dependent inhibitory effect of SV on the anterograde and retrograde dual pathways explains its specific antireentrant actions.
Recognition Failure: Another Case of Retrieval Failure
ERIC Educational Resources Information Center
Rabinowitz, Jan; And Others
A theoretical explanation of the phenomenon of recognition failure and a presentation of seven experiments investigating performance. Recognition failure is reduced when a more stringent recognition criterion is used, essentially eliminated when the proper access test is used and significantly reduced when variability in recognition performance is…
Debunking the lunar nodal tide in sea level data from the Northwest European shelf
NASA Astrophysics Data System (ADS)
Schmith, Torben; Thejll, Peter; Nielsen, Jacob W.
In a recent study (Hansen, et al, 2015. Sea-Level Forcing by Synchronization of 56- and 74-Year Oscillations with the Moon's Nodal Tide on the Northwest European Shelf (Eastern North Sea to Central Baltic Sea). Journal of Coastal Research, 31(5), 1041 - 1056, hereafter 'HAK'), the existence of an 18.6 year lunar nodal tide signal of considerable strength and other periodic signals in the North Sea -- Baltic Sea area is claimed. We criticize important aspects of the analysis presented in HAK and thereby cast doubt on their conclusions. HAK claim that 18.6 year variations in sea level are predicted by tidal theory, but this is not the case in general and therefore the existence of such variations must be explicitly shown. We calculate the amplitude spectrum of the annual sea level by harmonic analysis and find no significant peaks at the periods claimed by HAK. Next, we used the results given by HAK to reconstruct their decomposition, and formed the residuals by subtracting the decomposition from the original data. We found that a strong variability near 18.6 years in the residuals, showing that the decomposition by HAK overrepresents the variability at this period. This motivated us to redo HAK's analysis following their prescription and we found a seven times lower amplitude for the 18.6 year periodicity than claimed by HAK. Finally, we discuss HAK's mode selection-criteria, based on correlation coefficients of trending series and find them invalid. Therefore, we perform a significance test based on a Monte Carlo technique and conclude that none of the modes identified by HAK are statistically significant.
Theory of the nematic quantum critical point in a nodal superconductor
NASA Astrophysics Data System (ADS)
Kim, Eun-Ah
In the last several years, experimental evidence has accumulated in a variety of highly correlated electronic systems of new quantum phases which (for purely electronic reasons) spontaneously break the rotational (point group) symmetry of the underlying crystal. Such electron ``nematic'' phases have been seen in quantum Hall systems[1], in the metamagnetic metal Sr3Ru2O7[2], and more recently in magnetic neutron scattering studies of the high temperature superconductor, YBCO[3]. In the case of a high Tc superconductor, the quantum dynamics of nematic order parameter naturally couples strongly to quasiparticle (qp) excitations. In this talk, I will discuss our recent results on the effects of the coupling between quantum critical nematic fluctuations and the nodal qp's of a d-wave superconductor in the vicinity of a putative quantum critical point inside the superconducting phase. We solve a model system with N flavors of quasiparticles in the large N limit[4]. To leading order in 1/N, quantum fluctuations enhance the dispersion anisotropy of the nodal excitations, and cause strong scattering which critically broadens the quasiparticle peaks in the spectral function, except in the vicinity of ``the tips of the banana,'' where the qp's remain sharp. We will discuss the possible implications of our results to ARPES and STM experiments. [1] M.P. Lilly, K.B. Cooper, J.P. Eisenstein, L.N. Pfeiffer, and K.W. West, PRL 83, 824 (1999). [2] R. A. Borzi and S. A. Grigera and J. Farrell and R. S. Perry and S. J. S. Lister and S. L. Lee and D. A. Tennant and Y. Maeno and A. P. Mackenzie, Science 315, 214 (2007). [3] V. Hinkov, D. Haug, B. Fauqu'e, P. Bourges, Y. Sidis, A. Ivanov, C. Bernhard, C. T. Lin, B. Keimer, unpublished. [4] E.-A. Kim, M. Lawler, P. Oreto, E. Fradkin, S. Kivelson, cond-mat/0705.4099.
The nodal count {0,1,2,3,…} implies the graph is a tree
Band, Ram
Sturm's oscillation theorem states that the nth eigenfunction of a Sturm–Liouville operator on the interval has n−1 zeros (nodes) (Sturm 1836 J. Math. Pures Appl. 1, 106–186; 373–444). This result was generalized for all metric tree graphs (Pokornyĭ et al. 1996 Mat. Zametki 60, 468–470 (doi:10.1007/BF02320380); Schapotschnikow 2006 Waves Random Complex Media 16, 167–178 (doi:10.1080/1745530600702535)) and an analogous theorem was proved for discrete tree graphs (Berkolaiko 2007 Commun. Math. Phys. 278, 803–819 (doi:10.1007/S00220-007-0391-3); Dhar & Ramaswamy 1985 Phys. Rev. Lett. 54, 1346–1349 (doi:10.1103/PhysRevLett.54.1346); Fiedler 1975 Czechoslovak Math. J. 25, 607–618). We prove the converse theorems for both discrete and metric graphs. Namely if for all n, the nth eigenfunction of the graph has n−1 zeros, then the graph is a tree. Our proofs use a recently obtained connection between the graph's nodal count and the magnetic stability of its eigenvalues (Berkolaiko 2013 Anal. PDE 6, 1213–1233 (doi:10.2140/apde.2013.6.1213); Berkolaiko & Weyand 2014 Phil. Trans. R. Soc. A 372, 20120522 (doi:10.1098/rsta.2012.0522); Colin de Verdière 2013 Anal. PDE 6, 1235–1242 (doi:10.2140/apde.2013.6.1235)). In the course of the proof, we show that it is not possible for all (or even almost all, in the metric case) the eigenvalues to exhibit a diamagnetic behaviour. In addition, we develop a notion of 'discretized' versions of a metric graph and prove that their nodal counts are related to those of the metric graph. PMID:24344337
Majorana vortex-bound states in three-dimensional nodal noncentrosymmetric superconductors
NASA Astrophysics Data System (ADS)
Chang, Po-Yao; Matsuura, Shunji; Schnyder, Andreas P.; Ryu, Shinsei
Noncentrosymmetric superconductors (NCSs), characterized by antisymmetric spin-orbit coupling and a mixture of spin-singlet and spin-triplet pairing components, are promising candidate materials for topological superconductivity. An important hallmark of topological superconductors is the existence of protected zero-energy states at surfaces or in vortex cores. Here we investigate Majorana vortex-bound states in three-dimensional nodal and fully gapped NCSs by combining analytical solutions of Bogoliubov-de Gennes (BdG) equations in the continuum with exact diagonalization of BdG Hamiltonians. We show that depending on the crystal point-group symmetries and the topological properties of the bulk Bogoliubov-quasiparticle wave functions, different types of zero-energy Majorana modes can appear inside the vortex core. We find that for nodal NCSs with tetragonal point group C4 v the vortex states are dispersionless along the vortex line, forming one-dimensional Majorana flat bands, while for NCSs with D4 point-group symmetry the vortex modes are helical Majorana states with a linear dispersion along the vortex line. NCSs with monoclinic point group C2, on the other hand, do not exhibit any zero-energy vortex-bound states. We show that in the case of the C4 v (D4) point group the stability of these Majorana zero modes is guaranteed by a combination of reflection (π rotation), time-reversal, and particle-hole symmetry. Considering continuous deformations of the quasiparticle spectrum in the presence of vortices, we show that the flat-band vortex-bound states of C4 v point-group NCSs can be adiabatically connected to the dispersionless vortex-bound states of time-reversal symmetric Weyl superconductors. Experimental implications of our results for thermal transport and tunneling measurements are discussed.
Nodal upstaging during lung cancer resection is associated with surgical approach
Martin, Jeremiah T.; Durbin, Eric B.; Chen, Li; Gal, Tamas; Mahan, Angela; Ferraris, Victor; Zwischenberger, Joseph
Background Recent reports demonstrate that thoracoscopic lobectomy for lung cancer may be associated with lower rates of surgical upstaging. We queried a state-wide cancer registry for differences in upstaging rates and survival by surgical approach. Methods The Kentucky Cancer Registry (KCR) collects data, including centralized pathology reporting, on cancer patients treated statewide. We performed a retrospective review from 2010-2012 to examine clinical and pathologic stage. We assessed rates of upstaging and whether or not the surgical approach, thoracotomy (THOR) versus minimally invasive techniques (VATS), had an impact on final pathologic stage and survival. Results The KCR database from 2010 to 2012 contained information on 2830 lung cancer cases, 1964 having THOR and 500 having VATS resections. Preoperatively, 36.4% of THOR were clinically stage 1a vs. 47.4% % VATS (p=0.0002). Of these, final pathologic stage remained stage 1a in 30.5% of THOR and 38.0% of VATS (p=0.0002). The overall nodal upstaging rate for THOR was 9.9% and 4.8% for VATS (p=0.002). There was decreased nodal upstaging with VATS, independent of tumor size and extent of resection (OR 0.6, 95% CI 0.387-0.985, p=0.04). However there was improved survival with VATS compared with THOR (HR 0.733, 95% CI 0.592-0.907, p = 0.0042). Conclusions Consistent with other reports, we demonstrate a lower upstaging rate with VATS. Nevertheless, there is a survival advantage in VATS patients. Although selection bias may play a role in these observed differences, the improved quality of life measures associated with VATS, may explain survival improvement despite lower surgical upstaging. PMID:26428690
Risk factor analysis for central nodal metastasis in papillary thyroid carcinoma.
Mao, Ling-Na; Wang, Ping; Li, Zhi-Yu; Wang, Yong; Song, Zheng-Ya
Lymph node involvement is associated with recurrence in papillary thyroid carcinoma (PTC). The central neck compartment (level VI) lymph nodes are at the greatest risk of metastases from PTC, but the role of central neck dissection (CND) remains controversial, particularly in PTC without clinical cervical lymph node metastasis (cN0). The present study aimed to identify risk factors of central cervical nodal metastasis and the safety of CND in patients with cN0 PTC. The current study retrospectively investigated 389 patients who had been followed up for 12.0-25.5 months after surgery, and were divided into positive or negative lymph node involvement groups according to the pathological results subsequent to this surgery. Univariate and multivariate analyses were used to study the risk factor of central node involvement. The mean tumor size was 0.71±0.35 cm (range, 0.1-2.0 cm). There was no significant difference in the rate of central lymph node involvement based on age (<45 or ≥45 years) or tumor focality (unifocal or multifocal). However, there were significant differences based on gender, extra-thyroid invasion and tumor size (P<0.05). The incidence of transient hypoparathyroidism and transient vocal cord paralysis following CND was 12.34 and 4.11%, respectively. No patient experienced permanent hypoparathyroidism or vocal cord paralysis. One patient (1/389; 0.23%) experienced disease recurrence during the follow-up. A larger tumor size and the male gender were significantly associated with the central nodal metastasis rate for cN0 PTC with a tumor size of <2.0 cm. CND for cN0 PTC patients was safe and the tumor-associated recurrence rate following CND plus total thyroidectomy was low. The present study suggests that CND should be conducted for male cN0 PTC patients with a larger tumor size (≥0.5 cm).
Loess failure in northeast Afghanistan
NASA Astrophysics Data System (ADS)
Shroder, John F.; Schettler, Megan Jensen; Weihs, Brandon J.
Mass movements in northeastern Afghanistan include large-scale rockslides and complex slope failures, as well as failures in loess. The loess region in northeastern Afghanistan occurs in the Badakhshan and Takhar provinces and was likely created by dust blown to the east from the Karakum Desert and the alluvial plains of northern Afghanistan. This loessic dust was deposited against the Hindu Kush mountain range which rises up along the eastern half of Afghanistan as a result of transpressional tectonism. It overlies less permeable crystalline and sedimentary bedrocks such as Triassic granite, Proterozoic gneiss, and Miocene and Pliocene clastics in the area with the largest concentration of slope failures. Thirty-four loess slides and flows were mapped and analyzed using remote satellite imagery over digital elevation models on Google Earth™. This source enabled location, classification, and measurement of failures. Findings revealed that most failed slopes faced north, west, and northwest. This trend can be explained possibly as different moisture contents resulting from the primarily westerly wind direction, which may cause more precipitation to be deposited on west-facing slopes, and sun position during the hottest part of the day. Additionally, the easterly rising Hindu Kush range may cause more slope area to face west in the study region. Other contributing factors could be the very high seismicity of the area, which may cause rapid dry fluidized loess flows, and landscape modification by humans. Several loess slope failures appear to be generated by water concentration through irrigation ditches and possible rutted tire tracks, which can create tunneling between the loess and its less permeable bedrock. Causes and effects of loess failure in Afghanistan need to be investigated in more depth. Further study may lead to the adoption of more sustainable and safe farming practices and more informed housing locations, which may prevent loss of property, crop, and
Impact of FDG-PET/CT Imaging on Nodal Staging for Head-And-Neck Squamous Cell Carcinoma
Murakami, Ryuji . E-mail: firstname.lastname@example.com; Uozumi, Hideaki; Hirai, Toshinori; Nishimura, Ryuichi; Shiraishi, Shinya; Ota, Kazutoshi D.D.S.; Murakami, Daizo; Tomiguchi, Seiji; Oya, Natsuo; Katsuragawa, Shigehiko; Yamashita, Yasuyuki
Purpose: To evaluate the impact of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) imaging on nodal staging for head-and-neck squamous cell carcinoma (SCC). Methods and Materials: The study population consisted of 23 patients with head-and-neck SCC who were evaluated with FDG-PET/CT and went on to neck dissection. Two observers consensually determined the lesion size and maximum standardized uptake value (SUV{sub max}) and compared the results with pathologic findings on nodal-level involvement. Two different observers (A and B) independently performed three protocols for clinical nodal staging. Methods 1, 2, and 3 were based on conventional modalities, additional visual information from FDG-PET/CT images, and FDG-PET/CT imaging alone with SUV data, respectively. Results: All primary tumors were visualized with FDG-PET/CT. Pathologically, 19 positive and 93 negative nodal levels were identified. The SUV{sub max} overlapped in negative and positive nodes <15 mm in diameter. According to receiver operating characteristics analysis, the size-based SUV{sub max} cutoff values were 1.9, 2.5, and 3.0 for lymph nodes <10 mm, 10-15 mm, and >15 mm, respectively. These cutoff values yielded 79% sensitivity and 99% specificity for nodal-level staging. For Observer A, the sensitivity and specificity in Methods 1, 2, and 3 were 68% and 94%, 68% and 99%, and 84% and 99%, respectively, and Method 3 yielded significantly higher accuracy than Method 1 (p = 0.0269). For Observer B, Method 3 yielded the highest sensitivity (84%) and specificity (99%); however, the difference among the three protocols was not statistically significant. Conclusion: Imaging with FDG-PET/CT with size-based SUV{sub max} cutoff values is an important modality for radiation therapy planning.
Diffusion-Weighted MRI for Nodal Staging of Head and Neck Squamous Cell Carcinoma: Impact on Radiotherapy Planning
Dirix, Piet; Vandecaveye, Vincent; De Keyzer, Frederik; Op de beeck, Katya; Poorten, Vincent Vander; Delaere, Pierre; Verbeken, Eric; Hermans, Robert; Nuyts, Sandra
Purpose: To evaluate the use of diffusion-weighted magnetic resonance imaging (DW-MRI) for nodal staging and its impact on radiotherapy (RT) planning. Methods and Materials: Twenty-two patients with locally advanced head and neck squamous cell carcinoma underwent contrast-enhanced computed tomography (CT), as well as MRI (with routine and DW sequences) prior to neck dissection. After topographic correlation, lymph nodes were evaluated microscopically with prekeratin immunostaining. Pathology results were correlated with imaging findings and an RT planning study was performed for these surgically treated patients. One set of target volumes was based on conventional imaging only, and another set was based on the corresponding DW-MRI images. A third reference set was contoured based solely on pathology results. Results: A sensitivity of 89% and a specificity of 97% per lymph node were found for DW-MRI. Nodal staging agreement between imaging and pathology was significantly stronger for DW-MRI (kappa = 0.97; 95% confidence interval [CI], 0.84-1.00) than for conventional imaging (kappa = 0.56; 95% CI, 0.16-0.96; p = 0.019, by McNemar's test). For both imaging modalities, the absolute differences between RT volumes and those obtained by pathology were calculated. Using an exact paired Wilcoxon test, the observed difference was significantly larger for conventional imaging than for DW-MRI for nodal gross tumor volume (p = 0.0013), as well as for nodal clinical target volume (p = 0.0415) delineation. Conclusions: These results suggest that DW-MRI is superior to conventional imaging for preradiotherapy nodal staging of head and neck squamous cell carcinoma, and provides a potential impact on organsparing and tumor control.
Stem cell-derived nodal-like cardiomyocytes as a novel pharmacologic tool: insights from sinoatrial node development and function.
Barbuti, Andrea; Robinson, Richard B
Since the first reports on the isolation and differentiation of stem cells, and in particular since the early success in driving these cells down a cardiac lineage, there has been interest in the potential of such preparations in cardiac regenerative therapy. Much of the focus of such research has been on improving mechanical function after myocardial infarction; however, electrophysiologic studies of these preparations have revealed a heterogeneous mix of action potential characteristics, including some described as "pacemaker" or "nodal-like," which in turn led to interest in the therapeutic potential of these preparations in the treatment of rhythm disorders; several proof-of-concept studies have used these cells to create a biologic alternative to electronic pacemakers. Further, there are additional potential applications of a preparation of pacemaker cells derived from stem cells, for example, in high-throughput screens of new chronotropic agents. All such applications require reasonably efficient methods for selecting or enriching the "nodal-like" cells, however, which in turn depends on first defining what constitutes a nodal-like cell since not all pacemaking cells are necessarily of nodal lineage. This review discusses the current state of the field in terms of characterizing sinoatrial-like cardiomyocytes derived from embryonic and induced pluripotent stem cells, markers that might be appropriate based on the current knowledge of the gene program leading to sinoatrial node development, what functional characteristics might be expected and desired based on studies of the sinoatrial node, and recent efforts at enrichment and selection of nodal-like cells.
NASA Technical Reports Server (NTRS)
Keeton, S. C.
Review of state of the art concerning glass failure mechanisms and fatigue theories discusses brittle fracture in glass, fatigue mechanisms, fatigue behavior, environmental effects on failure rate, and aging.
[Understanding heart failure].
Boo, José Fernando Guadalajara
Heart failure is a disease with several definitions. The term "heart failure" is used by has brougth about confusion in the terminology. For this reason, the value of the ejection fraction (< 0.40 or < 0.35) is used in most meganalyses on the treatment of heart failure, avoiding the term "heart failure" that is a confounding concept. In this paper we carefully analyze the meaning of contractility, ventricular function or performance, preload, afterload, heart failure, compensation mechanisms in heart failure, myocardial oxygen consumption, inadequate, adequate and inappropriate hypertrophy, systole, diastole, compliance, problems of relaxation, and diastolic dysfunction. Their definitions are supported by the original scientific descriptions in an attempt to clarify the concepts about ventricular function and heart failure and, in this way, use the same scientific language about the meaning of ventricular function, heart failure, and diastolic dysfunction.
Failure prediction of thin beryllium sheets used in spacecraft structures
NASA Astrophysics Data System (ADS)
Roschke, Paul N.; Mascorro, Edward; Papados, Photios; Serna, Oscar R.
The primary objective of this study is to develop a method for prediction of failure of thin beryllium sheets that undergo complex states of stress. Major components of the research include experimental evaluation of strength parameters for cross-rolled beryllium sheet, application of the Tsai-Wu failure criterion to plate bending problems, development of a high order failure criterion, application of the new criterion to a variety of structures, and incorporation of both failure criteria into a finite element code. A Tsai-Wu failure model for SR-200 sheet material is developed from available tensile data, experiments carried out by NASA on two circular plates, and compression and off-axis experiments performed in this study. The failure surface obtained from the resulting criterion forms an ellipsoid. By supplementing experimental data used in the the two-dimensional criterion and modifying previously suggested failure criteria, a multi-dimensional failure surface is proposed for thin beryllium structures. The new criterion for orthotropic material is represented by a failure surface in six-dimensional stress space. In order to determine coefficients of the governing equation, a number of uniaxial, biaxial, and triaxial experiments are required. Details of these experiments and a complementary ultrasonic investigation are described in detail. Finally, validity of the criterion and newly determined mechanical properties is established through experiments on structures composed of SR200 sheet material. These experiments include a plate-plug arrangement under a complex state of stress and a series of plates with an out-of-plane central point load. Both criteria have been incorporated into a general purpose finite element analysis code. Numerical simulation incrementally applied loads to a structural component that is being designed and checks each nodal point in the model for exceedance of a failure criterion. If stresses at all locations do not exceed the failure
Failure prediction of thin beryllium sheets used in spacecraft structures
NASA Technical Reports Server (NTRS)
Roschke, Paul N.; Mascorro, Edward; Papados, Photios; Serna, Oscar R.
The primary objective of this study is to develop a method for prediction of failure of thin beryllium sheets that undergo complex states of stress. Major components of the research include experimental evaluation of strength parameters for cross-rolled beryllium sheet, application of the Tsai-Wu failure criterion to plate bending problems, development of a high order failure criterion, application of the new criterion to a variety of structures, and incorporation of both failure criteria into a finite element code. A Tsai-Wu failure model for SR-200 sheet material is developed from available tensile data, experiments carried out by NASA on two circular plates, and compression and off-axis experiments performed in this study. The failure surface obtained from the resulting criterion forms an ellipsoid. By supplementing experimental data used in the the two-dimensional criterion and modifying previously suggested failure criteria, a multi-dimensional failure surface is proposed for thin beryllium structures. The new criterion for orthotropic material is represented by a failure surface in six-dimensional stress space. In order to determine coefficients of the governing equation, a number of uniaxial, biaxial, and triaxial experiments are required. Details of these experiments and a complementary ultrasonic investigation are described in detail. Finally, validity of the criterion and newly determined mechanical properties is established through experiments on structures composed of SR200 sheet material. These experiments include a plate-plug arrangement under a complex state of stress and a series of plates with an out-of-plane central point load. Both criteria have been incorporated into a general purpose finite element analysis code. Numerical simulation incrementally applied loads to a structural component that is being designed and checks each nodal point in the model for exceedance of a failure criterion. If stresses at all locations do not exceed the failure
Failures in psychodynamic psychotherapy.
Gold, Jerry; Stricker, George
This article addresses the issue of failures in psychodynamic psychotherapy. Drawing on the clinical and research literatures, and utilizing our clinical experiences, we first describe and define criteria for success and failure in treatment. We then review five factors that can lead to failure: client factors, therapist factors, technical factors, relationship factors, and environmental factors. We illustrate our presentation with a case example, and conclude by discussing ways in which the likelihood of failures in psychodynamic treatment can be lowered.
Sweat, M.E.
An ammonia tank failure at Hawkeye Chemical of Clinton, Iowa is discussed. The tank was a double-wall, 27,000 metric-ton tank built in 1968 and commissioned in December 1969. The paper presented covers the cause of the failure, repair, and procedural changes made to prevent recurrence of the failure. (JMT)
Lee, Christopher S; Auld, Jonathan
Heart failure is a complex and multisystem clinical syndrome that results from impaired ventricular contractility and/or relaxation. Hypertension, diabetes mellitus, and coronary artery disease are common antecedents to heart failure. The main pathogenic mechanisms involved in heart failure include sympathetic nervous and renin-angiotensin-aldosterone system activation, as well as inflammation. A detailed history and physical examination and additional diagnostic tests may be needed to diagnose heart failure. Most treatment strategies target neurohormonal systems. Nonpharmacologic interventions and effective engagement in self-care are also important in overall heart failure management. Therapeutic strategies are geared toward prolonging life and optimizing quality of life.
The failure of earthquake failure models
Gomberg, J.
In this study I show that simple heuristic models and numerical calculations suggest that an entire class of commonly invoked models of earthquake failure processes cannot explain triggering of seismicity by transient or "dynamic" stress changes, such as stress changes associated with passing seismic waves. The models of this class have the common feature that the physical property characterizing failure increases at an accelerating rate when a fault is loaded (stressed) at a constant rate. Examples include models that invoke rate state friction or subcritical crack growth, in which the properties characterizing failure are slip or crack length, respectively. Failure occurs when the rate at which these grow accelerates to values exceeding some critical threshold. These accelerating failure models do not predict the finite durations of dynamically triggered earthquake sequences (e.g., at aftershock or remote distances). Some of the failure models belonging to this class have been used to explain static stress triggering of aftershocks. This may imply that the physical processes underlying dynamic triggering differs or that currently applied models of static triggering require modification. If the former is the case, we might appeal to physical mechanisms relying on oscillatory deformations such as compaction of saturated fault gouge leading to pore pressure increase, or cyclic fatigue. However, if dynamic and static triggering mechanisms differ, one still needs to ask why static triggering models that neglect these dynamic mechanisms appear to explain many observations. If the static and dynamic triggering mechanisms are the same, perhaps assumptions about accelerating failure and/or that triggering advances the failure times of a population of inevitable earthquakes are incorrect.
Numerical study on the impact of the 18.6-year period nodal tidal cycle on water masses in the subarctic North Pacific
NASA Astrophysics Data System (ADS)
Osafune, S.; Yasuda, I.
A series of numerical experiments is performed to test the hypothesis that temporal variations in localized strong tidal mixing related to the 18.6-year period nodal tidal cycle induce water mass variations. It is suggested that enhanced mixing around the Bering Sea, as that around the Okhotsk Sea, have an impact on water masses broadly in the North Pacific including the Bering Sea and the Okhotsk Sea. Oscillatory tidal mixing with a 18.6-year period reproduces water mass variations in salinity and isopycnal potential temperature around the subarctic North Pacific that are qualitatively consistent with observed variations. When the amplitude of oscillatory vertical diffusivity is 15% of the long-term mean (and even when the amplitude is as small as 3 cm2/s, as obtained for a long-term mean of 20 cm2/s), the amplitude of the salinity variation near regions of strong mixing is smaller than but on the same order of magnitude as that observed. The induced salinity anomaly spreads broadly, over a distance of several hundreds of kilometers, by mean currents with a short lag time of less than 3 years, and is suggested to influence the model winter mixed layer over broad regions. These results support the hypothesis stated above and suggest that it is necessary to clarify spatial and temporal variations in tidal mixing to reproduce both the mean states of and temporal variations in water masses of the subarctic North Pacific.
Stage III Melanoma in the Axilla: Patterns of Regional Recurrence After Surgery With and Without Adjuvant Radiation Therapy
Pinkham, Mark B.; Foote, Matthew C.; Burmeister, Elizabeth; Thomas, Janine; Meakin, Janelle; Smithers, B. Mark; Burmeister, Bryan H.
Purpose: To describe the anatomic distribution of regionally recurrent disease in patients with stage III melanoma in the axilla after curative-intent surgery with and without adjuvant radiation therapy. Methods and Materials: A single-institution, retrospective analysis of a prospective database of 277 patients undergoing curative-intent treatment for stage III melanoma in the axilla between 1992 and 2012 was completed. For patients who received radiation therapy and those who did not, patterns of regional recurrence were analyzed, and univariate analyses were performed to assess for potential factors associated with location of recurrence. Results: There were 121 patients who received adjuvant radiation therapy because their clinicopathologic features conferred a greater risk of regional recurrence. There were 156 patients who received no radiation therapy. The overall axillary control rate was 87%. There were 37 patients with regional recurrence; 17 patients had received adjuvant radiation therapy (14%), and 20 patients (13%) had not. The likelihood of in-field nodal recurrence was significantly less in the adjuvant radiation therapy group (P=.01) and significantly greater in sites adjacent to the axilla (P=.02). Patients with high-risk clinicopathologic features who did not receive adjuvant radiation therapy also tended to experience in-field failure rather than adjacent-field failure. Conclusions: Patients who received adjuvant radiation therapy were more likely to experience recurrence in the adjacent-field regions rather than in the in-field regions. This may not simply reflect higher-risk pathology. Using this data, it may be possible to improve outcomes by reducing the number of adjacent-field recurrences after adjuvant radiation therapy.
Kidney Failure: What to Expect
... Kidneys & How They Work Kidney Disease A-Z Kidney Failure What is kidney failure and how is it treated? Kidney failure ... Methods for Kidney Failure: Peritoneal Dialysis . Peritoneal dialysis Kidney Transplant A kidney transplant places a healthy kidney ...
Nodal-line pairing with 1D-3D coupled Fermi surfaces: A model motivated by Cr-based superconductors
NASA Astrophysics Data System (ADS)
Wachtel, Gideon; Kim, Yong Baek
Motivated by the recent discovery of a new family of chromium-based superconductors, we consider a two-band model, where a band of electrons dispersing only in one direction interacts with a band of electrons dispersing in all three directions. Strong 2 kf density fluctuations in the one-dimensional band induces attractive interactions between the three-dimensional electrons, which, in turn, makes the system superconducting. Solving the associated Eliashberg equations, we obtain a gap function which is peaked at the "poles" of the three-dimensional Fermi sphere, and decreases towards the "equator." When strong enough local repulsion is included, the gap actually changes sign around the equator and nodal rings are formed. These nodal rings manifest themselves in several experimentally observable quantities, some of which resemble unconventional observations in the newly discovered superconductors which motivated this work.
High-latitude oceanic variability associated with the 18.6-year nodal tide
NASA Astrophysics Data System (ADS)
Royer, Thomas C.
Ocean temperatures in the upper 250 m in the northern North Pacific (60°N, 149°W) increased by more than 1°C from 1972 to 1986 but are now decreasing. Subsurface temperature anomalies are well correlated (˜0.58) with the air temperature anomalies at Sitka, Alaska; hence the coastal air temperatures can be used as a proxy data set to extend the ocean temperature time series back to 1828. Up to 30% of the low-frequency variance can be accounted for with the 18.6-year nodal signal. Additionally, spectral analysis of these air temperature variations indicates a significant low-frequency peak in the range of the 18.6-year signal. Similar low-frequency signals have been reported for Hudson Bay air temperatures since 1700, for sea surface temperatures in the North Atlantic from 1876 to 1939, and for sea level in the high-latitude southern hemisphere. The water column temperature variations presented here are the first evidence that the upper ocean is responding to this very long period tidal forcing. An enhanced high-latitude response to the 18.6-year forcing is predicted by equilibrium tide theory, and it should be most evident at latitudes poleward of about 50°. These low-frequency ocean-atmosphere variations must be considered in high-latitude assessments of global climate change, since they are of the same magnitude as many of the predicted global changes.
CD20-Positive nodal natural killer/T-cell lymphoma with cutaneous involvement.
Tsai, Yi-Chiun; Chen, Chi-Kuan; Wu, Yu-Hung
CD20-positive natural killer (NK)/T-cell lymphoma is extremely rare. We describe a case of a CD20-positive nodal NK/T-cell lymphoma with cutaneous involvement in a 32-year-old man. The patient presented with fever, night sweats, right inguinal lymphadenopathy and multiple violaceous to erythematous nodules and plaques on the back and bilateral legs. Immunohistochemical analysis showed diffusely and strongly positive staining for CD3, CD3 epsilon, CD43, CD56, TIA-1 and CD20 but negative staining for other B-cell markers, including CD79a and PAX-5 and T-cell markers CD5 and CD7. The tumor cell nuclei were diffusely positive for Epstein-Barr virus-encoded RNA in situ hybridization. A partial clinical response was observed after chemotherapy, indicated by the decreased size of the lymph nodes and skin lesions. It is a diagnostic challenge to deal with lymphoma cells that present with the surface proteins of both T- and B-cells.
Identification of cell-type-specific mutations in nodal T-cell lymphomas
Nguyen, T B; Sakata-Yanagimoto, M; Asabe, Y; Matsubara, D; Kano, J; Yoshida, K; Shiraishi, Y; Chiba, K; Tanaka, H; Miyano, S; Izutsu, K; Nakamura, N; Takeuchi, K; Miyoshi, H; Ohshima, K; Minowa, T; Ogawa, S; Noguchi, M; Chiba, S
Recent genetic analysis has identified frequent mutations in ten-eleven translocation 2 (TET2), DNA methyltransferase 3A (DNMT3A), isocitrate dehydrogenase 2 (IDH2) and ras homolog family member A (RHOA) in nodal T-cell lymphomas, including angioimmunoblastic T-cell lymphoma and peripheral T-cell lymphoma, not otherwise specified. We examined the distribution of mutations in these subtypes of mature T-/natural killer cell neoplasms to determine their clonal architecture. Targeted sequencing was performed for 71 genes in tumor-derived DNA of 87 cases. The mutations were then analyzed in a programmed death-1 (PD1)-positive population enriched with tumor cells and CD20-positive B cells purified by laser microdissection from 19 cases. TET2 and DNMT3A mutations were identified in both the PD1+ cells and the CD20+ cells in 15/16 and 4/7 cases, respectively. All the RHOA and IDH2 mutations were confined to the PD1+ cells, indicating that some, including RHOA and IDH2 mutations, being specific events in tumor cells. Notably, we found that all NOTCH1 mutations were detected only in the CD20+ cells. In conclusion, we identified both B- as well as T-cell-specific mutations, and mutations common to both T and B cells. These findings indicate the expansion of a clone after multistep and multilineal acquisition of gene mutations. PMID:28157189
Light Spectral Quality Effects on the Growth of Potato (Solanum Tuberosum L.) Nodal Cuttings in Vitro
NASA Technical Reports Server (NTRS)
Wilson, Deborah A.; Weigel, Russell C.; Wheeler, Raymond M.; Sager, John C.
The effects of light spectral quality on the growth of in vitro nodal cuttings of potato (Solanum tuberosum L.) cultivars Norland, Superior, Kennebec, and Denali were examined. The different light spectra were provided by Vita-Lite fluorescent (VF) (a white light control), blue fluorescent (BF), red fluorescent (RF), low-pressure sodium (LPS), and a combination of low-pressure sodium plus cool-white fluorescent lamps (LPS/CWF). For cultivars, stem lengths after 4 wks were longest under LPS, follow by RF, LPS/CWF, VF, and BF (in descending order). Microscopic studies revealed that cells were shortest when cultured in BF or VF environments, and were longest in RF or LPS lamp environments. The highest number axillary branches occurred on plantlets grown with LPS or LPS/CWF, whereas the lowest number occurred with BF. No leaf or stem edema (callus or gall-like growths) occurred iwth LPS or LPS/cwf lighting, and no edema occurred on cv. Norland plantlets, regardless of lighting. Results suggest that shoot morphologic development of in vitro grown potato plants can be controlled by controlling irradiant spectral quality.
Alignment of a three-mirror anastigmatic telescope using nodal aberration theory.
Gu, Zhiyuan; Yan, Changxiang; Wang, Yang
Most computer-aided alignment methods for optical systems are based on numerical algorithms at present, which omit aberration theory. This paper presents a novel alignment algorithm for three-mirror anastigmatic (TMA) telescopes using Nodal Aberration Theory (NAT). The aberration field decenter vectors and boresight error of misaligned TMA telescopes are derived. Two alignment models based on 3rd and 5th order NAT are established successively and compared in the same alignment example. It is found that the average and the maximum RMS wavefront errors in the whole field of view of 0.3° × 0.15° are 0.063 λ (λ = 1 μm) and 0.068 λ respectively after the 4th alignment action with the 3rd order model, and 0.011 λ and 0.025 λ (nominal values) respectively after the 3rd alignment action with the 5th order model. Monte-Carlo alignment simulations are carried out with the 5th order model. It shows that the 5th order model still has good performance even when the misalignment variables are large (-1 mm≤linear misalignment≤1 mm, -0.1°≤angular misalignment≤0.1°), and multiple iterative alignments are needed when the misalignment variables increase.
Active optical alignment of off-axis telescopes based on nodal aberration theory.
Zhang, Xiaobin; Zhang, Dong; Xu, Shuyan; Ma, Hongcai
Our paper mainly separates the specific aberration contributions of third-order astigmatism and third-order coma from the total aberration fields, on the framework of the modified nodal aberration theory (NAT), for the perturbed off-axis telescope. Based on the derived aberration functions, two alignment models for the same off-axis two-mirror telescope are established and compared. Among them, one is based on third-order NAT, the other is based on fifth-order NAT. By comparison, it is found that the calculated perturbations based on fifth-order NAT are more accurate. It illustrates that third-order astigmatism and third-order coma contributed from fifth-order aberrations can't be neglected in the alignment process. Then the fifth-order NAT is used for the alignment of off-axis three-mirror telescopes. After simulation, it is found that the perturbed off-axis three-mirror telescope can be perfectly aligned as well. To further demonstrate the application of the alignment method based on fifth-order NAT (simplified as NAT method), Monte-Carlo simulations for both off-axis two-mirror telescope and off-axis three-mirror telescope are conducted in the end. Meantime, a comparison between NAT method and sensitivity table method is also conducted. It is proven that the computation accuracy of NAT method is much higher, especially in poor conditions.
Directed nanoscale self-assembly of molecular wires interconnecting nodal points using Monte Carlo simulations
Boscoboinik, A. M.; Manzi, S. J.; Tysoe, W. T.; Pereyra, V. D.; Boscoboinik, J. A.
The influence of directing agents in the self-assembly of molecular wires to produce two-dimensional electronic nanoarchitectures is studied here using a Monte Carlo approach to simulate the effect of arbitrarily locating nodal points on a surface, from which the growth of self-assembled molecular wires can be nucleated. This is compared to experimental results reported for the self-assembly of molecular wires when 1,4-phenylenediisocyanide (PDI) is adsorbed on Au(111). The latter results in the formation of (Au-PDI)n organometallic chains, which were shown to be conductive when linked between gold nanoparticles on an insulating substrate. The present study analyzes, by means of stochastic methods, the influence of variables that affect the growth and design of self-assembled conductive nanoarchitectures, such as the distance between nodes, coverage of the monomeric units that leads to the formation of the desired architectures, and the interaction between the monomeric units. As a result, this study proposes an approach and sets the stage for the production of complex 2D nanoarchitectures using a bottom-up strategy but including the use of current state-of-the-art top-down technology as an integral part of the self-assembly strategy.
Directed nanoscale self-assembly of molecular wires interconnecting nodal points using Monte Carlo simulations
Boscoboinik, A. M.; Manzi, S. J.; Tysoe, W. T.; ...
The influence of directing agents in the self-assembly of molecular wires to produce two-dimensional electronic nanoarchitectures is studied here using a Monte Carlo approach to simulate the effect of arbitrarily locating nodal points on a surface, from which the growth of self-assembled molecular wires can be nucleated. This is compared to experimental results reported for the self-assembly of molecular wires when 1,4-phenylenediisocyanide (PDI) is adsorbed on Au(111). The latter results in the formation of (Au-PDI)n organometallic chains, which were shown to be conductive when linked between gold nanoparticles on an insulating substrate. The present study analyzes, by means of stochasticmore » methods, the influence of variables that affect the growth and design of self-assembled conductive nanoarchitectures, such as the distance between nodes, coverage of the monomeric units that leads to the formation of the desired architectures, and the interaction between the monomeric units. As a result, this study proposes an approach and sets the stage for the production of complex 2D nanoarchitectures using a bottom-up strategy but including the use of current state-of-the-art top-down technology as an integral part of the self-assembly strategy.« less
A "gentle" nodal suspension for measurements of the acoustic attenuation in materials.
Cesarini, E; Lorenzini, M; Campagna, E; Martelli, F; Piergiovanni, F; Vetrano, F; Losurdo, G; Cagnoli, G
Loss angle measurements in ultralow mechanical loss materials is normally affected by a large systematic error due to the excess losses introduced by the suspension system used to hold the samples. Crystals such as sapphire and silicon or amorphous materials such as fused silica can have loss angles in the range of 10(-10)-10(-7); such materials are of extreme interest in the detection of small displacements as it is required in quantum measurements, frequency stabilization, Micro Electro-Mechanical Systems (MEMS), and gravitational wave research. In the system proposed here the sample is suspended in equilibrium on top of a sphere, touching on one of the nodal points of vibration. The advantage of this system, as compared to others used so far, is twofold: (i) one surface only of the sample is touched and the contact surface is minimized because of the absence of applied forces; (ii) some relevant parameters of the suspension can be measured and eventually varied, giving the experimentalist the possibility to identify whether the measured loss is limited by the suspension system in use or it is an intrinsic property of the sample under investigation. The measurements of a 75 mm diameter and 3 mm thickness disk of Suprasil 311 gave a loss angle phi of 5x10(-8).
Nodal energy weighted transformation: A mistuning projection and its application to FLADE™ turbines
NASA Astrophysics Data System (ADS)
Fitzner, Colin; Epureanu, Bogdan I.; Filippi, Sergio
In recent years, several researchers have developed reduced-order models (ROMs) to efficiently and accurately calculate the forced response of blisks with known small mistuning. Small mistuning consists of the small blade-to-blade structural differences which destroy the inherent cyclic symmetry of the structure. This paper presents a nodal energy weighted transformation (NEWT) which can be used to construct ROMs of mistuned blisks and dual flow path systems, such as FLADE™ turbines. The NEWT approach can be interpreted as a hybrid of two existing techniques: component mode mistuning (CMM) and the subset of nominal modes (SNM). Similar to the previous methods, NEWT assumes that the mistuned modes of the system are a linear combination of tuned modes. However, NEWT differs from its predecessors in the blisk substructuring and in the mistuning projection. Numerical results obtained using full order models, CMM, and NEWT are presented and compared over multiple frequency ranges for a finite element model of a blisk and that of a FLADE™ turbine. These results show that ROMs based on NEWT have several attractive features: (a) the accuracy of the ROMs is comparable to ROMs based on CMM, and can be improved by increasing the size of the projection mode subset; (b) no necessary modifications are needed to analyze FLADE™ turbines; and (c) the response of all modes can be predicted well even if they are not blade dominated.
Lunar nodal tide and distance to the Moon during the Precambrian.
Walker, J C; Zahnle, K J
The pace of tidal evolution for the past approximately 450 Myr implies an Earth/Moon collision some 1,500-2,000 Myr BP, an event for which there is no corroborating evidence. Here we present the first direct determination of the lunar distance in the Precambrian. We interpret a 23.3 +/- 0.3-yr periodicity preserved in a 2,500 Myr BP Australian banded iron formation (BIF) as reflecting the climatic influence of the lunar nodal tide, which has been detected with its modern 18.6-yr periodicity in some modern climate records. The lunar distance at 2,500 Myr BP would then have been about 52 Earth radii. The implied history of Precambrian tidal friction is in accord with both the more recent palaeontological evidence and the long-term stability of the lunar orbit. The length of the Milankovitch cycles that modulate the ice ages today also evolve with the Earth-Moon system. Their detection in the Precambrian sedimentary record would then permit an independent determination of the lunar distance.
Uncompacted Myelin Lamellae and Nodal Ion Channel Disruption in POEMS Syndrome.
Hashimoto, Rina; Koike, Haruki; Takahashi, Mie; Ohyama, Ken; Kawagashira, Yuichi; Iijima, Masahiro; Sobue, Gen
To elucidate the significance of uncompacted myelin lamellae (UML) and ion channel disruption at the nodes of Ranvier in the polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome, we evaluated sural nerve biopsy specimens from 33 patients with POEMS syndrome and from 7 control patients. Uncompacted myelin lamellae distribution was assessed by electron microscopy and immunofluorescence microscopy. In the POEMS patient biopsies, UML were seen more frequently in small versus large myelinated fibers. Paranodes and Schmidt-Lanterman incisures, where normal physiologic UM is located, were frequently associated with UM. Widening of the nodes of Ranvier (i.e. segmental demyelination) was not associated with UML. There was axonal hollowing with neurofilament condensation at Schmidt-Lanterman incisures with abnormal UML, suggesting axonal damage at those sites in the POEMS patient biopsies. Myelin sheath irregularity was conspicuous in large myelinated fibers and was associated with abnormally widened bizarrely shaped Schmidt-Lanterman incisures. Indirect immunofluorescent studies revealed abnormalities of sodium (pan sodium) and potassium (KCNQ2) channels, even at nonwidened nodes of Ranvier. Thus, UML was not apparently associated with segmental demyelination but seemed to be associated with axonal damage. These observations suggest that nodal ion channel disruption may be associated with functional deficits in POEMS syndrome patient nerves.
Anisotropic softening of magnetic excitations along the nodal direction in superconducting cuprates
NASA Astrophysics Data System (ADS)
Guarise, M.; Piazza, B. Dalla; Berger, H.; Giannini, E.; Schmitt, T.; Rønnow, H. M.; Sawatzky, G. A.; van den Brink, J.; Altenfeld, D.; Eremin, I.; Grioni, M.
The high-Tc cuprate superconductors are close to antiferromagnetic order. Recent measurements of magnetic excitations have reported an intriguing similarity to the spin waves—magnons—of the antiferromagnetic insulating parent compounds, suggesting that magnons may survive in damped, broadened form throughout the phase diagram. Here we show by resonant inelastic X-ray scattering on Bi2Sr2CaCu2O8+δ (Bi-2212) that the analogy with spin waves is only partial. The magnon-like features collapse along the nodal direction in momentum space and exhibit a photon energy dependence markedly different from the Mott-insulating case. These observations can be naturally described by the continuum of charge and spin excitations of correlated electrons. The persistence of damped magnons could favour scenarios for superconductivity built from quasiparticles coupled to spin fluctuations. However, excitation spectra composed of particle-hole excitations suggest that superconductivity emerges from a coherent treatment of electronic spin and charge in the form of quasiparticles with very strong magnetic correlations.
Atrioventricular nodal ablation versus antiarrhythmic drugs after permanent pacemaker implantation for bradycardia-tachycardia syndrome.
Nagamoto, Yasutsugu; Inage, Tomohito; Yoshida, Teruhisa; Takeuchi, Tomohiro; Gondo, Takeki; Fukuda, Yujiro; Takii, Eiichi; Murotani, Kenta; Imaizumi, Tsutomu
Patients often require antiarrhythmic drugs to control tachycardia after permanent pacemaker implantation (PMI) for bradycardia-tachycardia syndrome. We compared atrioventricular nodal ablation (AVNA) to antiarrhythmic drugs after PMI for bradycardia-tachycardia syndrome. Twenty-eight symptomatic patients with bradycardia-tachycardia syndrome, all of which had a long pause after termination of paroxysmal atrial fibrillation, underwent PMI with RV lead placement at the mid-septum site. Among these patients, 14 underwent PMI and AVNA (AVNA group). The remaining 14 patients underwent PMI only, and continued to take anti-arrhythmic drugs (drug group). We compared cardiac function (cardio-thoracic ratio on chest X-ray, left atrial diameter, left ventricular end-diastolic dimension, and left ventricular-ejection fraction by echocardiography), exercise tolerance (6-min walking distance), symptoms, and the number of antiarrhythmic drugs just before and 6 months after PMI. Baseline characteristics were similar between the two groups, except for the number of antiarrhythmic drugs. Six months after PMI, cardiac function, exercise tolerance, and symptoms did not differ significantly between the two groups. Compared to the drug group (p < 0.01), the number of antiarrhythmic drugs was significantly smaller in the AVNA group 6 months after PMI. Patients who underwent AVNA concurrently with PMI with RV lead placement at the mid-septum site for bradycardia-tachycardia syndrome were able to reduce the intake of drugs and improve their tachycardia-related symptoms while maintaining cardiac function and exercise tolerance.
A nodal discontinuous Galerkin finite element method for nonlinear elastic wave propagation.
Bou Matar, Olivier; Guerder, Pierre-Yves; Li, YiFeng; Vandewoestyne, Bart; Van Den Abeele, Koen
A nodal discontinuous Galerkin finite element method (DG-FEM) to solve the linear and nonlinear elastic wave equation in heterogeneous media with arbitrary high order accuracy in space on unstructured triangular or quadrilateral meshes is presented. This DG-FEM method combines the geometrical flexibility of the finite element method, and the high parallelization potentiality and strongly nonlinear wave phenomena simulation capability of the finite volume method, required for nonlinear elastodynamics simulations. In order to facilitate the implementation based on a numerical scheme developed for electromagnetic applications, the equations of nonlinear elastodynamics have been written in a conservative form. The adopted formalism allows the introduction of different kinds of elastic nonlinearities, such as the classical quadratic and cubic nonlinearities, or the quadratic hysteretic nonlinearities. Absorbing layers perfectly matched to the calculation domain of the nearly perfectly matched layers type have been introduced to simulate, when needed, semi-infinite or infinite media. The developed DG-FEM scheme has been verified by means of a comparison with analytical solutions and numerical results already published in the literature for simple geometrical configurations: Lamb's problem and plane wave nonlinear propagation.
High-order nodal discontinuous Galerkin methods for the Maxwell eigenvalue problem.
Hesthaven, J S; Warburton, T
The Maxwell eigenvalue problem is known to pose difficulties for standard numerical methods, predominantly due to its large null space. As an alternative to the widespread use of Galerkin finite-element methods based on curl-conforming elements, we propose to use high-order nodal elements in a discontinuous element scheme. We consider both two- and three-dimensional problems and show the former to be without problems in a wide range of cases. Numerical experiments suggest the validity of this for general problems. For the three-dimensional eigenproblem, we encounter difficulties with a naive formulation of the scheme and propose minor modifications, intimately related to the discontinuous nature of the formulation, to overcome these concerns. We conclude by connecting the findings to time domain solution of Maxwell's equations. The discussion, analysis, and numerous computational experiments suggest that using discontinuous element schemes for solving Maxwell's equation in the frequency- or time-domain present a high-order accurate, efficient and robust alternative to classical Galerkin finite-element methods.
Mathematical Formalism for Designing Wide-Field X-Ray Telescopes: Mirror Nodal Positions and Detector Tilts
NASA Technical Reports Server (NTRS)
Elsner, R. F.; O'Dell, S. L.; Ramsey, B. D.; Weisskopf, M. C.
We provide a mathematical formalism for optimizing the mirror nodal positions along the optical axis and the tilt of a commonly employed detector configuration at the focus of a x-ray telescope consisting of nested mirror shells with known mirror surface prescriptions. We adopt the spatial resolution averaged over the field-of-view as the figure of merit M. A more complete description appears in our paper in these proceedings.
Prevalence of Common Non-Hodgkin Lymphomas and Subtypes of Hodgkin Lymphoma by Nodal Site of Involvement
Laurent, Camille; Do, Catherine; Gourraud, Pierre-Antoine; de Paiva, Geisilene Russano; Valmary, Séverine; Brousset, Pierre
Abstract Non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) represent a heterogeneous group of malignant lymphoid tumors, which have distinct histological and/or biological characteristics with preferential nodal involvement. However, none of the previous studies have assessed the prevalence of common NHL and HL subtypes at each nodal site of involvement. The aim of our study was to determine the prevalence of HL and NHL subtypes depending on their nodal sites of involvement. We conducted a single-center retrospective study of 938 lymphoma cases diagnosed in the Pathology Department of Toulouse Purpan Hospital in France between 2001 and 2008, taking into account the site that corresponded to the diagnostic biopsy. The most frequent sites were cervical lymph nodes (36.8% of all cases), inguinal lymph nodes (16.4%), axillary lymph nodes (11.9%), and supraclavicular lymph nodes (11%). We found an unexpected association between intraparotid nodes and nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) and between inguinal nodes and follicular lymphoma. The risk of having classical Hodgkin lymphoma (CHL) was 15 times greater in patients with mediastinal lymphoma compared to those with other sites of involvement. Regarding HL, nodal and extranodal mediastinal sites and supraclavicular nodes were more likely to be involved by nodular sclerosis Hodgkin lymphoma (NSCHL). In addition, intra-abdominal lymph nodes were more frequently involved by lymphocyte depleted Hodgkin lymphoma compared to inguinal nodes where NLPHL predominated. Our study shows that some lymph node sites have a disproportionate prevalence of specific subtypes of lymphoma. Identifying these sites may aid to diagnose and better elucidate the pathogenesis of these tumors. PMID:26107683
Long non-coding RNA GAS5 controls human embryonic stem cell self-renewal by maintaining NODAL signalling
Xu, Chen; Zhang, Yan; Wang, Qiaoling; Xu, Zhenyu; Jiang, Junfeng; Gao, Yuping; Gao, Minzhi; Kang, Jiuhong; Wu, Minjuan; Xiong, Jun; Ji, Kaihong; Yuan, Wen; Wang, Yue; Liu, Houqi
Long non-coding RNAs (lncRNAs) are known players in the regulatory circuitry of the self-renewal in human embryonic stem cells (hESCs). However, most hESC-specific lncRNAs remain uncharacterized. Here we demonstrate that growth-arrest-specific transcript 5 (GAS5), a known tumour suppressor and growth arrest-related lncRNA, is highly expressed and directly regulated by pluripotency factors OCT4 and SOX2 in hESCs. Phenotypic analysis shows that GAS5 knockdown significantly impairs hESC self-renewal, but its overexpression significantly promotes hESC self-renewal. Using RNA sequencing and functional analysis, we demonstrate that GAS5 maintains NODAL signalling by protecting NODAL expression from miRNA-mediated degradation. Therefore, we propose that the above pluripotency factors, GAS5 and NODAL form a feed-forward signalling loop that maintains hESC self-renewal. As this regulatory function of GAS5 is stem cell specific, our findings also indicate that the functions of lncRNAs may vary in different cell types due to competing endogenous mechanisms. PMID:27811843
An efficient in vitro regeneration protocol for a natural dye yielding plant, Strobilanthes flaccidifolious Nees., from nodal explants.
Deb, Chitta Ranjan; Arenmongla, T
Adventitious shoot buds formation from axillary buds of nodal segments of S. flaccidifolious was achieved on MS medium containing sucrose (3%, w/v), and a-naphthalene acetic acid (NAA; 3 microM) and benzyl adenine (3 microM) in combination. The nodal segments were primed on 'Growtak Sieve' for 48 h on MS medium containing sucrose (2%), polyvinyl pyrollidone (200 mgL(-1)) as antioxidant. About 80% of primed nodal segments responded positively and formed approximately 12 adventitious shoot buds per explants from explants collected during October-November months of every year. The shoot buds converted into plantlets on MS medium containing sucrose (3%) and kinetin (3 microM) where approximately 7 micro shoots developed per subculture after 8 weeks of culture. The regenerated micro shoots induced average 14 roots/plant on medium containing NAA (3 microM). The regenerates were hardened for 6-7 weeks on medium with 1/2MS salt solution and sucrose (2%) under normal laboratory condition before transferring to potting mix. About 70% transplants survived after two months of transfer.
Distinct modes of SMAD2 chromatin binding and remodeling shape the transcriptional response to NODAL/Activin signaling
Coda, Davide M; Gaarenstroom, Tessa; East, Philip; Patel, Harshil; Miller, Daniel S J; Lobley, Anna; Matthews, Nik; Stewart, Aengus; Hill, Caroline S
NODAL/Activin signaling orchestrates key processes during embryonic development via SMAD2. How SMAD2 activates programs of gene expression that are modulated over time however, is not known. Here we delineate the sequence of events that occur from SMAD2 binding to transcriptional activation, and the mechanisms underlying them. NODAL/Activin signaling induces dramatic chromatin landscape changes, and a dynamic transcriptional network regulated by SMAD2, acting via multiple mechanisms. Crucially we have discovered two modes of SMAD2 binding. SMAD2 can bind pre-acetylated nucleosome-depleted sites. However, it also binds to unacetylated, closed chromatin, independently of pioneer factors, where it induces nucleosome displacement and histone acetylation. For a subset of genes, this requires SMARCA4. We find that long term modulation of the transcriptional responses requires continued NODAL/Activin signaling. Thus SMAD2 binding does not linearly equate with transcriptional kinetics, and our data suggest that SMAD2 recruits multiple co-factors during sustained signaling to shape the downstream transcriptional program. DOI: http://dx.doi.org/10.7554/eLife.22474.001 PMID:28191871
Early complications. Respiratory failure.
Zwischenberger, J B; Alpard, S K; Bidani, A
Pulmonary complications following thoracic surgery are common and associated with significant morbidity and mortality. Respiratory failure after pneumonectomy occurs in approximately 5% to 15% of cases and significantly increases patient mortality. Strategies for ventilator support are based on the nature of the underlying complication and the pathophysiology of respiratory failure. This article describes the cause and pathophysiology of respiratory failure and pulmonary embolus postpneumonectomy. Diagnosis, management, and innovative therapies are also reviewed.
Trans-nodal migration of resident dendritic cells into medullary interfollicular regions initiates immunity to influenza vaccine
Woodruff, Matthew C.; Heesters, Balthasar A.; Herndon, Caroline N.; Groom, Joanna R.; Thomas, Paul G.; Luster, Andrew D.; Turley, Shannon J.
Dendritic cells (DCs) are well established as potent antigen-presenting cells critical to adaptive immunity. In vaccination approaches, appropriately stimulating lymph node–resident DCs (LNDCs) is highly relevant to effective immunization. Although LNDCs have been implicated in immune response, their ability to directly drive effective immunity to lymph-borne antigen remains unclear. Using an inactive influenza vaccine model and whole node imaging approaches, we observed surprising responsiveness of LNDC populations to vaccine arrival resulting in a transnodal repositioning into specific antigen collection sites within minutes after immunization. Once there, LNDCs acquired viral antigen and initiated activation of viral specific CD4+ T cells, resulting in germinal center formation and B cell memory in the absence of skin migratory DCs. Together, these results demonstrate an unexpected stimulatory role for LNDCs where they are capable of rapidly locating viral antigen, driving early activation of T cell populations, and independently establishing functional immune response. PMID:25049334
Krugman, Scott D; Dubowitz, Howard
Failure to thrive is a condition commonly seen by primary care physicians. Prompt diagnosis and intervention are important for preventing malnutrition and developmental sequelae. Medical and social factors often contribute to failure to thrive. Either extreme of parental attention (neglect or hypervigilance) can lead to failure to thrive. About 25 percent of normal infants will shift to a lower growth percentile in the first two years of life and then follow that percentile; this should not be diagnosed as failure to thrive. Infants with Down syndrome, intrauterine growth retardation, or premature birth follow different growth patterns than normal infants. Many infants with failure to thrive are not identified unless careful attention is paid to plotting growth parameters at routine checkups. A thorough history is the best guide to establishing the etiology of the failure to thrive and directing further evaluation and management. All children with failure to thrive need additional calories for catch-up growth (typically 150 percent of the caloric requirement for their expected, not actual, weight). Few need laboratory evaluation. Hospitalization is rarely required and is indicated only for severe failure to thrive and for those whose safety is a concern. A multidisciplinary approach is recommended when failure to thrive persists despite intervention or when it is severe.
Differential role of Sloan-Kettering Institute (Ski) protein in Nodal and transforming growth factor-beta (TGF-β)-induced Smad signaling in prostate cancer cells.
Vo, BaoHan T; Cody, Bianca; Cao, Yang; Khan, Shafiq A
Transforming growth factor-beta (TGF-β) signaling pathways contain both tumor suppressor and tumor promoting activities. We have demonstrated that Nodal, another member of the TGF-β superfamily, and its receptors are expressed in prostate cancer cells. Nodal and TGF-β exerted similar biological effects on prostate cells; both inhibited proliferation in WPE, RWPE1 and DU145 cells, whereas neither had any effect on the proliferation of LNCaP or PC3 cells. Interestingly, Nodal and TGF-β induced migration in PC3 cells, but not in DU145 cells. TGF-β induced predominantly phosphorylation of Smad3, whereas Nodal induced phosphorylation of only Smad2. We also determined the expression and differential role of Ski, a corepressor of Smad2/3, in Nodal and TGF-β signaling in prostate cancer cells. Similar levels of Ski mRNA were found in several established prostate cell lines; however, high levels of Ski protein were only detected in prostate cancer cells and prostate cancer tissue samples. Exogenous Nodal and TGF-β had no effects on Ski mRNA levels. On the other hand, TGF-β induced a rapid degradation of Ski protein mediated by the proteasomal pathway, whereas Nodal had no effect on Ski protein. Reduced Ski levels correlated with increased basal and TGF-β-induced Smad2/3 phosphorylation. Knockdown of endogenous Ski reduced proliferation in DU145 cells and enhanced migration of PC3 cells. We conclude that high levels of Ski expression in prostate cancer cells may be responsible for repression of TGF-β and Smad3 signaling, but Ski protein levels do not influence Nodal and Smad2 signaling.
Multiple roles of Activin/Nodal, bone morphogenetic protein, fibroblast growth factor and Wnt/β-catenin signalling in the anterior neural patterning of adherent human embryonic stem cell cultures
Lupo, Giuseppe; Novorol, Claire; Smith, Joseph R.; Vallier, Ludovic; Miranda, Elena; Alexander, Morgan; Biagioni, Stefano; Pedersen, Roger A.; Harris, William A.
Several studies have successfully produced a variety of neural cell types from human embryonic stem cells (hESCs), but there has been limited systematic analysis of how different regional identities are established using well-defined differentiation conditions. We have used adherent, chemically defined cultures to analyse the roles of Activin/Nodal, bone morphogenetic protein (BMP), fibroblast growth factor (FGF) and Wnt/β-catenin signalling in neural induction, anteroposterior patterning and eye field specification in hESCs. We show that either BMP inhibition or activation of FGF signalling is required for effective neural induction, but these two pathways have distinct outcomes on rostrocaudal patterning. While BMP inhibition leads to specification of forebrain/midbrain positional identities, FGF-dependent neural induction is associated with strong posteriorization towards hindbrain/spinal cord fates. We also demonstrate that Wnt/β-catenin signalling is activated during neural induction and promotes acquisition of neural fates posterior to forebrain. Therefore, inhibition of this pathway is needed for efficient forebrain specification. Finally, we provide evidence that the levels of Activin/Nodal and BMP signalling have a marked influence on further forebrain patterning and that constitutive inhibition of these pathways represses expression of eye field genes. These results show that the key mechanisms controlling neural patterning in model vertebrate species are preserved in adherent, chemically defined hESC cultures and reveal new insights into the signals regulating eye field specification. PMID:23576785
Accuracy of MRI in Prediction of Tumour Thickness and Nodal Stage in Oral Tongue and Gingivobuccal Cancer With Clinical Correlation and Staging
Parihar, Pratap Singh; Parihar, Akhilesh; Goel, Ashok Kumar; Waghwani, Kapil; Gupta, Richa; Bhutekar, Umesh
Introduction Squamous cell carcinoma of lower gingivo-buccal complex and tongue are the most common cancer in the Indian sub-continent. The value of imaging in the staging of Oral Squamous Cell Carcinoma (OSCC) is in judging operability, assessment of the prognostic characteristics and dimensions of the primary tumour, depth of tumour invasion, the presence of cervical metastasis and detection of bone infiltration. Aim This study evaluated squamous cell carcinomas of the oral cavity (tongue and gingivo-buccal complex) on the basis of their appearance, soft tissue extent, depth of tumour invasion and staging. Further, this study assessed the accuracy of MRI in the detection of cervical lymph nodal metastasis on the basis of ADC values on diffusion weighted MR sequence. Materials and Methods T1- and T2-weighted MR, diffusion-weighted sequences and post contrast T1W sequences were performed in various planes on biopsy proven squamous cell carcinomas (61 cases) involving tongue and/or gingivo-buccal region. Depth of tumour invasion was calculated on axial images of post contrast T1W images. The Apparent Diffusion Coefficient (ADC) was measured by using two b factors (500 and 1000 s/mm2). MRI findings were compared clinically and histopathologically. Results Average depth of invasion calculated on MRI was 8.47mm and by histopathology was 6.85mm. Pearson's correlation coefficient was 0.988. Shrinkage factor was 0.8. A 71% of patients with depth of invasion greater than 9mm showed evidence of cervical lymph nodal metastasis at one or another levels. Cut-off value to discriminate between malignant and benign lymph nodes was 1.038 x10-3 mm2/s in the present study. Conclusion Depth of tumour invasion in oral malignancies can be measured reliably on MRI which helps in predicting cervical lymph node metastasis. Benign or malignant cervical lymph nodes can be differentiated on diffusion-weighted imaging of MRI on the basis of their ADC values. PMID:27504375
Living with Respiratory Failure
... smoking. Emotional Issues and Support Living with respiratory failure may cause fear, anxiety, depression, and stress. Talk about how you feel with your health care team. Talking to a professional counselor also can ... to living with respiratory failure. You can see how other people who have ...
NASA Technical Reports Server (NTRS)
Watring, Dale A. (Inventor); Johnson, Martin L. (Inventor)
An ampoule failure system for use in material processing furnaces comprising a containment cartridge and an ampoule failure sensor. The containment cartridge contains an ampoule of toxic material therein and is positioned within a furnace for processing. An ampoule failure probe is positioned in the containment cartridge adjacent the ampoule for detecting a potential harmful release of toxic material therefrom during processing. The failure probe is spaced a predetermined distance from the ampoule and is chemically chosen so as to undergo a timely chemical reaction with the toxic material upon the harmful release thereof. The ampoule failure system further comprises a data acquisition system which is positioned externally of the furnace and is electrically connected to the ampoule failure probe so as to form a communicating electrical circuit. The data acquisition system includes an automatic shutdown device for shutting down the furnace upon the harmful release of toxic material. It also includes a resistance measuring device for measuring the resistance of the failure probe during processing. The chemical reaction causes a step increase in resistance of the failure probe whereupon the automatic shutdown device will responsively shut down the furnace.
Facing Challenges for Monte Carlo Analysis of Full PWR Cores : Towards Optimal Detail Level for Coupled Neutronics and Proper Diffusion Data for Nodal Kinetics
NASA Astrophysics Data System (ADS)
Nuttin, A.; Capellan, N.; David, S.; Doligez, X.; El Mhari, C.; Méplan, O.
Safety analysis of innovative reactor designs requires three dimensional modeling to ensure a sufficiently realistic description, starting from steady state. Actual Monte Carlo (MC) neutron transport codes are suitable candidates to simulate large complex geometries, with eventual innovative fuel. But if local values such as power densities over small regions are needed, reliable results get more difficult to obtain within an acceptable computation time. In this scope, NEA has proposed a performance test of full PWR core calculations based on Monte Carlo neutron transport, which we have used to define an optimal detail level for convergence of steady state coupled neutronics. Coupling between MCNP for neutronics and the subchannel code COBRA for thermal-hydraulics has been performed using the C++ tool MURE, developed for about ten years at LPSC and IPNO. In parallel with this study and within the same MURE framework, a simplified code of nodal kinetics based on two-group and few-point diffusion equations has been developed and validated on a typical CANDU LOCA. Methods for the computation of necessary diffusion data have been defined and applied to NU (Nat. U) and Th fuel CANDU after assembly evolutions by MURE. Simplicity of CANDU LOCA model has made possible a comparison of these two fuel behaviours during such a transient.
A stabilised nodal spectral element method for fully nonlinear water waves
NASA Astrophysics Data System (ADS)
Engsig-Karup, A. P.; Eskilsson, C.; Bigoni, D.
We present an arbitrary-order spectral element method for general-purpose simulation of non-overturning water waves, described by fully nonlinear potential theory. The method can be viewed as a high-order extension of the classical finite element method proposed by Cai et al. (1998) [5], although the numerical implementation differs greatly. Features of the proposed spectral element method include: nodal Lagrange basis functions, a general quadrature-free approach and gradient recovery using global L2 projections. The quartic nonlinear terms present in the Zakharov form of the free surface conditions can cause severe aliasing problems and consequently numerical instability for marginally resolved or very steep waves. We show how the scheme can be stabilised through a combination of over-integration of the Galerkin projections and a mild spectral filtering on a per element basis. This effectively removes any aliasing driven instabilities while retaining the high-order accuracy of the numerical scheme. The additional computational cost of the over-integration is found insignificant compared to the cost of solving the Laplace problem. The model is applied to several benchmark cases in two dimensions. The results confirm the high order accuracy of the model (exponential convergence), and demonstrate the potential for accuracy and speedup. The results of numerical experiments are in excellent agreement with both analytical and experimental results for strongly nonlinear and irregular dispersive wave propagation. The benefit of using a high-order - possibly adapted - spatial discretisation for accurate water wave propagation over long times and distances is particularly attractive for marine hydrodynamics applications.
Long term results of fast pathway ablation in atrioventricular nodal reentry tachycardia using a modified technique.
Mehta, D.; Gomes, J. A.
OBJECTIVE--To assess immediate and long term success of "fast" pathway catheter ablation with graded use of radiofrequency energy in patients with classic atrioventricular nodal reentrant tachycardia (AVNRT) and evaluate clinical, procedure related, and electrophysiological features affecting long term results. DESIGN--31 consecutive patients with classic AVNRT at electrophysiological study, who were candidates for radiofrequency ablation. Patients were followed for an average of 24 months after ablation. SETTING--All studies and ablations were performed in an electrophysiological laboratory under fluoroscopic guidance using standard electrophysiological techniques. INTERVENTION--Radiofrequency application was performed at the site of proximal His bundle electrogram with A:V ratio of > 1. It was started at 10 W with increment of 5 W to a maximum of 25 W at 60 s. With the onset of junctional rhythm, atrial pacing was begun in order to monitor the PR interval. Application was terminated prematurely with a non-conducted P wave, continued prolongation of the PR interval beyond 50% of the baseline, or a threefold rise in impedance. RESULTS--Successful ablation was possible in 30/31 patients (97%) with an average of seven applications (range 1-10). It was associated with significant prolongation of PR interval (P < 0.001) and AV Wenckebach cycle length (P = 0.01). Ventriculo-atrial conduction was abolished in 24/30 patients (82%) with successful ablation. Two patients developed transient complete heart block (3 and 12 min) and one persistent right branch block. Four patients had late recurrence. Presence of ventriculo-atrial block was the only electrophysiological index predictive of long term success (P = 0.01). CONCLUSIONS--Graded use of radiofrequency energy and atrial pacing to monitor PR interval decreases the risk of atrioventricular block in patients undergoing fast pathway ablation for AVNRT. Ventriculo-atrial block is predictive of long term success and should
Pediatric-type nodal follicular lymphoma: a biologically distinct lymphoma with frequent MAPK pathway mutations.
Louissaint, Abner; Schafernak, Kristian T; Geyer, Julia T; Kovach, Alexandra E; Ghandi, Mahmoud; Gratzinger, Dita; Roth, Christine G; Paxton, Christian N; Kim, Sunhee; Namgyal, Chungdak; Morin, Ryan; Morgan, Elizabeth A; Neuberg, Donna S; South, Sarah T; Harris, Marian H; Hasserjian, Robert P; Hochberg, Ephraim P; Garraway, Levi A; Harris, Nancy Lee; Weinstock, David M
Pediatric-type nodal follicular lymphoma (PTNFL) is a variant of follicular lymphoma (FL) characterized by limited-stage presentation and invariably benign behavior despite often high-grade histological appearance. It is important to distinguish PTNFL from typical FL in order to avoid unnecessary treatment; however, this distinction relies solely on clinical and pathological criteria, which may be variably applied. To define the genetic landscape of PTNFL, we performed copy number analysis and exome and/or targeted sequencing of 26 PTNFLs (16 pediatric and 10 adult). The most commonly mutated gene in PTNFL was MAP2K1, encoding MEK1, with a mutation frequency of 43%. All MAP2K1 mutations were activating missense mutations localized to exons 2 and 3, which encode negative regulatory and catalytic domains, respectively. Missense mutations in MAPK1 (2/22) and RRAS (1/22) were identified in cases that lacked MAP2K1 mutations. The second most commonly mutated gene in PTNFL was TNFRSF14, with a mutation frequency of 29%, similar to that seen in limited-stage typical FL (P = .35). PTNFL was otherwise genomically bland and specifically lacked recurrent mutations in epigenetic modifiers (eg, CREBBP, KMT2D). Copy number aberrations affected a mean of only 0.5% of PTNFL genomes, compared with 10% of limited-stage typical FL genomes (P < .02). Importantly, the mutational profiles of PTNFLs in children and adults were highly similar. Together, these findings define PTNFL as a biologically and clinically distinct indolent lymphoma of children and adults characterized by a high prevalence of MAPK pathway mutations and a near absence of mutations in epigenetic modifiers.
Respiratory Organ Motion and Dosimetric Impact on Breast and Nodal Irradiation
Qi, X. Sharon; White, Julia; Rabinovitch, Rachel; Merrell, Kenneth; Sood, Amit; Bauer, Anderson; Wilson, J. Frank; Miften, Moyed; Li, X. Allen
Purpose: To examine the respiratory motion for target and normal structures during whole breast and nodal irradiation and the resulting dosimetric impact. Methods and Materials: Four-dimensional CT data sets of 18 patients with early-stage breast cancer were analyzed retrospectively. A three-dimensional conformal dosimetric plan designed to irradiate the breast was generated on the basis of CT images at 20% respiratory phase (reference phase). The reference plans were copied to other respiratory phases at 0% (end of inspiration) and 50% (end of expiration) to simulate the effects of breathing motion on whole breast irradiation. Dose-volume histograms, equivalent uniform dose, and normal tissue complication probability were evaluated and compared. Results: Organ motion of up to 8.8 mm was observed during free breathing. A large lung centroid movement was typically associated with a large shift of other organs. The variation of planning target volume coverage during a free breathing cycle is generally within 1%-5% (17 of 18 patients) compared with the reference plan. However, up to 28% of V{sub 45} variation for the internal mammary nodes was observed. Interphase mean dose variations of 2.2%, 1.2%, and 1.4% were observed for planning target volume, ipsilateral lung, and heart, respectively. Dose variations for the axillary nodes and brachial plexus were minimal. Conclusions: The doses delivered to the target and normal structures are different from the planned dose based on the reference phase. During normal breathing, the dosimetric impact of respiratory motion is clinically insignificant with the exception of internal mammary nodes. However, noticeable degradation in dosimetric plan quality may be expected for the patients with large respiratory motion.
Pediatric-type nodal follicular lymphoma: a biologically distinct lymphoma with frequent MAPK pathway mutations
Schafernak, Kristian T.; Geyer, Julia T.; Kovach, Alexandra E.; Ghandi, Mahmoud; Gratzinger, Dita; Roth, Christine G.; Paxton, Christian N.; Kim, Sunhee; Namgyal, Chungdak; Morin, Ryan; Morgan, Elizabeth A.; Neuberg, Donna S.; South, Sarah T.; Harris, Marian H.; Hasserjian, Robert P.; Hochberg, Ephraim P.; Garraway, Levi A.; Harris, Nancy Lee; Weinstock, David M.
Pediatric-type nodal follicular lymphoma (PTNFL) is a variant of follicular lymphoma (FL) characterized by limited-stage presentation and invariably benign behavior despite often high-grade histological appearance. It is important to distinguish PTNFL from typical FL in order to avoid unnecessary treatment; however, this distinction relies solely on clinical and pathological criteria, which may be variably applied. To define the genetic landscape of PTNFL, we performed copy number analysis and exome and/or targeted sequencing of 26 PTNFLs (16 pediatric and 10 adult). The most commonly mutated gene in PTNFL was MAP2K1, encoding MEK1, with a mutation frequency of 43%. All MAP2K1 mutations were activating missense mutations localized to exons 2 and 3, which encode negative regulatory and catalytic domains, respectively. Missense mutations in MAPK1 (2/22) and RRAS (1/22) were identified in cases that lacked MAP2K1 mutations. The second most commonly mutated gene in PTNFL was TNFRSF14, with a mutation frequency of 29%, similar to that seen in limited-stage typical FL (P = .35). PTNFL was otherwise genomically bland and specifically lacked recurrent mutations in epigenetic modifiers (eg, CREBBP, KMT2D). Copy number aberrations affected a mean of only 0.5% of PTNFL genomes, compared with 10% of limited-stage typical FL genomes (P < .02). Importantly, the mutational profiles of PTNFLs in children and adults were highly similar. Together, these findings define PTNFL as a biologically and clinically distinct indolent lymphoma of children and adults characterized by a high prevalence of MAPK pathway mutations and a near absence of mutations in epigenetic modifiers. PMID:27325104
Generalized energy failure criterion.
Qu, R T; Zhang, Z J; Zhang, P; Liu, Z Q; Zhang, Z F
Discovering a generalized criterion that can predict the mechanical failure of various different structural materials is one of ultimate goals for scientists in both material and mechanics communities. Since the first study on the failure criterion of materials by Galileo, about three centuries have passed. Now we eventually find the "generalized energy criterion", as presented here, which appears to be one universal law for various different kinds of materials. The validity of the energy criterion for quantitatively predicting the failure is experimentally confirmed using a metallic glass. The generalized energy criterion reveals the competition and interaction between shear and cleavage, the two fundamental inherent failure mechanisms, and thus provides new physical insights into the failure prediction of materials and structural components.
Acute Decompensated Heart Failure
Joseph, Susan M.; Cedars, Ari M.; Ewald, Gregory A.; Geltman, Edward M.; Mann, Douglas L.
Hospitalizations for acute decompensated heart failure are increasing in the United States. Moreover, the prevalence of heart failure is increasing consequent to an increased number of older individuals, as well as to improvement in therapies for coronary artery disease and sudden cardiac death that have enabled patients to live longer with cardiovascular disease. The main treatment goals in the hospitalized patient with heart failure are to restore euvolemia and to minimize adverse events. Common in-hospital treatments include intravenous diuretics, vasodilators, and inotropic agents. Novel pharmaceutical agents have shown promise in the treatment of acute decompensated heart failure and may simplify the treatment and reduce the morbidity associated with the disease. This review summarizes the contemporary management of patients with acute decompensated heart failure. PMID:20069075
Generalized energy failure criterion
Qu, R. T.; Zhang, Z. J.; Zhang, P.; Liu, Z. Q.; Zhang, Z. F.
Discovering a generalized criterion that can predict the mechanical failure of various different structural materials is one of ultimate goals for scientists in both material and mechanics communities. Since the first study on the failure criterion of materials by Galileo, about three centuries have passed. Now we eventually find the "generalized energy criterion", as presented here, which appears to be one universal law for various different kinds of materials. The validity of the energy criterion for quantitatively predicting the failure is experimentally confirmed using a metallic glass. The generalized energy criterion reveals the competition and interaction between shear and cleavage, the two fundamental inherent failure mechanisms, and thus provides new physical insights into the failure prediction of materials and structural components. PMID:26996781
Technology integration box beam failure study
NASA Technical Reports Server (NTRS)
Shuart, Mark J.; Ambur, Damodar R.; Davis, D. D., Jr.; Davis, R. C.; Farley, G. L.; Lotts, C. G.; Wang, J. T.
The objective of this paper is to describe current results from an on-going study of the mechanisms that led to the failure of the TIBB. Experimental and analytical results are presented. Experimental results include load, strain, and deflection data for the TIBB (Technology Integration Box Beam). An analytical investigation was conducted to compliment the experimental investigation and to gain additional insight into the TIBB structural response. Analytical results include strain and deflection results from a global analysis of the TIBB. A local analysis of the failure region is being completed. These analytical results are validated through comparisons with the experimental results from the TIBB tests. The experimental and analytical results from the TIBB tests are used to determine a sequence of events that may have resulted in failure of the TIBB. A potential cause of failure is high stresses in a stiffener runout region. Typical analytical results are presented for a stiffener runout specimen that is being defined to simulate the TIBB failure mechanisms. The results of this study are anticipated to provide better understanding of potential failure mechanisms in composite aircraft structures, to lead to future design improvements, and to identify needed analytical tools for design and analysis.
Failure and recovery in dynamical networks
Böttcher, L.; Luković, M.; Nagler, J.; Havlin, S.; Herrmann, H. J.
Failure, damage spread and recovery crucially underlie many spatially embedded networked systems ranging from transportation structures to the human body. Here we study the interplay between spontaneous damage, induced failure and recovery in both embedded and non-embedded networks. In our model the network's components follow three realistic processes that capture these features: (i) spontaneous failure of a component independent of the neighborhood (internal failure), (ii) failure induced by failed neighboring nodes (external failure) and (iii) spontaneous recovery of a component. We identify a metastable domain in the global network phase diagram spanned by the model's control parameters where dramatic hysteresis effects and random switching between two coexisting states are observed. This dynamics depends on the characteristic link length of the embedded system. For the Euclidean lattice in particular, hysteresis and switching only occur in an extremely narrow region of the parameter space compared to random networks. We develop a unifying theory which links the dynamics of our model to contact processes. Our unifying framework may help to better understand controllability in spatially embedded and random networks where spontaneous recovery of components can mitigate spontaneous failure and damage spread in dynamical networks. PMID:28155876
Failure and recovery in dynamical networks
NASA Astrophysics Data System (ADS)
Böttcher, L.; Luković, M.; Nagler, J.; Havlin, S.; Herrmann, H. J.
Failure, damage spread and recovery crucially underlie many spatially embedded networked systems ranging from transportation structures to the human body. Here we study the interplay between spontaneous damage, induced failure and recovery in both embedded and non-embedded networks. In our model the network's components follow three realistic processes that capture these features: (i) spontaneous failure of a component independent of the neighborhood (internal failure), (ii) failure induced by failed neighboring nodes (external failure) and (iii) spontaneous recovery of a component. We identify a metastable domain in the global network phase diagram spanned by the model's control parameters where dramatic hysteresis effects and random switching between two coexisting states are observed. This dynamics depends on the characteristic link length of the embedded system. For the Euclidean lattice in particular, hysteresis and switching only occur in an extremely narrow region of the parameter space compared to random networks. We develop a unifying theory which links the dynamics of our model to contact processes. Our unifying framework may help to better understand controllability in spatially embedded and random networks where spontaneous recovery of components can mitigate spontaneous failure and damage spread in dynamical networks.
[Heart failure and comorbidities].
Boully, Clémence; Hanon, Olivier
Heart failure is a frequent disease in the elderly. Its clinical presentation is less typical and the prognosis more severe than in younger subjects because heart failure occurs in patients with multiple comorbidities. A comprehensive geriatric assessment should therefore be performed to detect the vulnerabilities and manage the comorbidities. The main diseases associated with heart failure are dementia, depression, malnutrition, atrial fibrillation, coronary artery disease, orthostatic hypotension, renal failure, anemia and iron deficiency. Comorbidities worsen heart failure and makes its treatment more difficult. The identification and treatment of comorbidities improve the prognosis in terms of mortality but especially in terms of quality of life. Caution with drugs is necessary because of pharmacokinetic or pharmacodynamic changes related to aging and the comorbidities. In this context, clinical and laboratory monitoring should be increased, mostly during an acute event (acute heart failure, infection, dehydration, fall, new therapy…). Therefore, the follow-up of elderly patients with heart failure requires a multidisciplinary approach that involves close cooperation between cardiologists, geriatricians, general practitioners, nurses, and pharmacists.
Mechanical failure of cavities in poroelastic media
Ozkan, G.; Ortoleva, P.
The stress-induced failure of cavities in poroelastic media is investigated using an analytical solution of the elastic matrix inclusion problem of Eshelby and a rock failure criterion. The elastic properties of the porous matrix surrounding the cavity are modeled using a self-consistent version of the theory of Berryman while the cavity collapse criterion is based on a failure condition calibrated as a function of matrix mineralogy, grain size and porosity. The influence of the latter textural variables as well as pore fluid pressure and cavity shape and orientation relative to the far-field stress are evaluated. The region of failure on the cavity surface is identified. These results are applied to the prediction of vug stability in a sedimentary basin in the context of vuggy reservoir exploration and production.
Bacak, Stephen J; Thornburg, Loralei L
Acute liver failure is a rare but life-threatening medical emergency in pregnancy whose true incidence remains unknown. Many cases of acute liver failure are caused by pregnancy-related conditions such as acute fatty liver of pregnancy and HELLP syndrome. However, acute deterioration in liver function can also be caused by drug overdose, viral infections, and an exacerbation of underlying chronic liver disease. This article provides an overview of the normal liver changes that occur during pregnancy, and summarizes the most common conditions and general management strategies of liver failure during pregnancy.
Damage mechanics - failure modes
Krajcinovic, D.; Vujosevic, M.
The present study summarizes the results of the DOE sponsored research program focused on the brittle failure of solids with disordered microstructure. The failure is related to the stochastic processes on the microstructural scale; namely, the nucleation and growth of microcracks. The intrinsic failure modes, such as the percolation, localization and creep rupture, are studied by emphasizing the effect of the micro-structural disorder. A rich spectrum of physical phenomena and new concepts that emerges from this research demonstrates the reasons behind the limitations of traditional, deterministic, and local continuum models.
The high temperature superconductivity in cuprates: physics of the pseudogap region
NASA Astrophysics Data System (ADS)
Cea, Paolo
We discuss the physics of the high temperature superconductivity in hole doped copper oxide ceramics in the pseudogap region. Starting from an effective reduced Hamiltonian relevant to the dynamics of holes injected into the copper oxide layers proposed in a previous paper, we determine the superconductive condensate wavefunction. We show that the low-lying elementary condensate excitations are analogous to the rotons in superfluid 4He. We argue that the rotons-like excitations account for the specific heat anomaly at the critical temperature. We discuss and compare with experimental observations the London penetration length, the Abrikosov vortices, the upper and lower critical magnetic fields, and the critical current density. We give arguments to explain the origin of the Fermi arcs and Fermi pockets. We investigate the nodal gap in the cuprate superconductors and discuss both the doping and temperature dependence of the nodal gap. We suggest that the nodal gap is responsible for the doping dependence of the so-called nodal Fermi velocity detected in angle resolved photoemission spectroscopy studies. We discuss the thermodynamics of the nodal quasielectron liquid and their role in the low temperature specific heat. We propose that the ubiquitous presence of charge density wave in hole doped cuprate superconductors in the pseudogap region originates from instabilities of the nodal quasielectrons driven by the interaction with the planar CuO2 lattice. We investigate the doping dependence of the charge density wave gap and the competition between charge order and superconductivity. We discuss the effects of external magnetic fields on the charge density wave gap and elucidate the interplay between charge density wave and Abrikosov vortices. Finally, we examine the physics underlying quantum oscillations in the pseudogap region.
Paraxial left-sided nodal expression and the start of left-right patterning in the early chick embryo.
Tsikolia, Nikoloz; Schröder, Silke; Schwartz, Peter; Viebahn, Christoph
A common element during early left-right patterning of the vertebrate body is left-sided nodal expression in the early-somite stage lateral plate mesoderm. Leftward cell movements near the node of the gastrulating chick embryo recently offered a plausible mechanism for breaking the presomite-stage molecular symmetry in those vertebrates which lack rotating cilia on the notochord or equivalent tissues. However, the temporal and functional relationships between generation of the known morphological node asymmetry, onset of leftward cell movements and establishment of stable molecular asymmetry in the chick remain unresolved. This study uses high-resolution light microscopy and in situ gene expression analysis to show that intranodal cell rearrangement during the phase of counter-clockwise node torsion at stage 4+ is immediately followed by symmetry loss and rearrangement of shh and fgf8 expression in node epiblast between stages 5- and 5+. Surprisingly, left-sided nodal expression starts at stage 5-, too, but lies in the paraxial mesoderm next to the forming notochordal plate, and can be rendered symmetrical by minimal mechanical disturbance of distant tissue integrity at stage 4. The "premature" paraxial nodal expression together with morphological and molecular asymmetries in, and near, midline compartments occurring at defined substages of early gastrulation help to identify a new narrow time window for early steps in left-right patterning in the chick and support the concept of a causal relationship between a-still enigmatic-chiral (motor) protein, cell movements and incipient left-right asymmetry in the amniote embryo.
Involvement of both sodium influx and potassium efflux in ciguatoxin-induced nodal swelling of frog myelinated axons.
Mattei, César; Molgó, Jordi; Benoit, Evelyne
Ciguatoxins, mainly produced by benthic dinoflagellate Gambierdiscus species, are responsible for a complex human poisoning known as ciguatera. Previous pharmacological studies revealed that these toxins activate voltage-gated Na+ channels. In frog nodes of Ranvier, ciguatoxins induce spontaneous and repetitive action potentials (APs) and increase axonal volume that may explain alterations of nerve functioning in intoxicated humans. The present study aimed determining the ionic mechanisms involved in Pacific ciguatoxin-1B (P-CTX-1B)-induced membrane hyperexcitability and subsequent volume increase in frog nodes of Ranvier, using electrophysiology and confocal microscopy. The results reveal that P-CTX-1B action is not dependent on external Cl- ions since it was not affected by substituting Cl- by methylsulfate ions. In contrast, substitution of external Na+ by Li+ ions suppressed spontaneous APs and prevented nodal swelling. This suggests that P-CTX-1B-modified Na+ channels are not selective to Li+ ions and/or are blocked by these ions, and that Na+ influx through Na+ channels opened during spontaneous APs is required for axonal swelling. The fact that the K+ channel blocker tetraethylammonium modified, but did not suppress, spontaneous APs and greatly reduced nodal swelling induced by P-CTX-1B indicates that K+ efflux might also be involved. This is supported by the fact that P-CTX-1B, when tested in the presence of both tetraethylammonium and the K+ ionophore valinomycin, produced the characteristic nodal swelling. It is concluded that, during the action of P-CTX-1B, water movements responsible for axonal swelling depend on both Na+ influx and K+ efflux. These results pave the way for further studies regarding ciguatera treatment.
Cranial location of level II lymph nodes in laryngeal cancer: Implications for elective nodal target volume delineation
Braam, Petra M. . E-mail: firstname.lastname@example.com; Raaijmakers, Cornelis P.J.; Terhaard, Chris
Purpose: To analyze the cranial distribution of level II lymph nodes in patients with laryngeal cancer to optimize the elective radiation nodal target volume delineation. Methods and Materials: The most cranially located metastatic lymph node was delineated in 67 diagnostic CT data sets. The minimum distance from the base of the skull (BOS) to the lymph node was determined. Results: A total of 98 lymph nodes were delineated including 62 ipsilateral and 36 contralateral lymph nodes. The mean ipsilateral and contralateral distance from the top of the most cranial metastatic lymph node to the BOS was 36 mm (range, -9-120; standard deviation [SD], 17.9) and 35 mm (range, 14-78; SD 15.0), respectively. Only 5% and 12% of the ipsilateral and 3% and 9% of the contralateral metastatic lymph nodes were located within 15 mm and 20 mm below the BOS, respectively. No significant differences were found between patients with only ipsilateral metastatic lymph nodes and patients with bilateral metastatic lymph nodes. Between tumors that do cross the midline and those that do not, no significant difference was found in the distance of the most cranial lymph node to the BOS and the occurrence ipsilateral or contralateral. Conclusions: Setting the cranial border of the nodal target volume 1.5 cm below the base of the skull covers 95% of the lymph nodes and should be considered in elective nodal irradiation for laryngeal cancer. Bilateral neck irradiation is mandatory, including patients with unilateral laryngeal cancer, when elective irradiation is advised.
... Heart failure - overview Heart pacemaker High blood pressure Implantable cardioverter-defibrillator Smoking - tips on how to quit ... ask your doctor How to read food labels Implantable cardioverter defibrillator - discharge Low-salt diet Mediterranean diet ...
... heart failure: Fast or difficult breathing Leg swelling (edema) Neck veins that stick out (are distended) Sounds ( ... pacemaker High blood pressure Implantable cardioverter-defibrillator Pulmonary edema Stable angina Ventricular assist device Patient Instructions ACE ...
Fiesta, J
When a medication error is coupled with a communication problem, a patient may experience significant injury. Cases involving communication breakdown, i.e, failure to communicate or listen, are discussed.
NASA Technical Reports Server (NTRS)
Nola, F. J. (Inventor)
A failure detector is provided for detecting unidirectional failures in triacs, particularly as used in power factor controllers for induction motors. In a first embodiment, the triac voltage waveform is sensed and upon detection of an unbalanced signal, corresponding to failure of the triac in either the positive or negative direction, the triac is turned full on in both directions. In a second embodiment, a pair of pulsed signals are derived, the pulse durations of which are proportional to the phase difference between the load current and voltage for each half cycle, and the triac is turned full on responsive to a difference in pulse duration between the half cycle signals. An unidirectional open circuit detector is adapted to use a signal from either of the first and second embodiment to turn the triac off in response to an open circuit failure in either direction.
Inverter ratio failure detector
NASA Technical Reports Server (NTRS)
Wagner, A. P.; Ebersole, T. J.; Andrews, R. E. (Inventor)
A failure detector which detects the failure of a dc to ac inverter is disclosed. The inverter under failureless conditions is characterized by a known linear relationship of its input and output voltages and by a known linear relationship of its input and output currents. The detector includes circuitry which is responsive to the detector's input and output voltages and which provides a failure-indicating signal only when the monitored output voltage is less by a selected factor, than the expected output voltage for the monitored input voltage, based on the known voltages' relationship. Similarly, the detector includes circuitry which is responsive to the input and output currents and provides a failure-indicating signal only when the input current exceeds by a selected factor the expected input current for the monitored output current based on the known currents' relationship.
CHF - tests; Congestive heart failure - tests; Cardiomyopathy - tests; HF - tests ... An echocardiogram (Echo) is a test that uses sound waves to create a moving picture of the heart. The picture is much more detailed than a plain ...
NASA Technical Reports Server (NTRS)
Hark, Frank; Britton, Paul; Ring, Robert; Novack, Steven
Space Launch System (SLS) Agenda: Objective; Key Definitions; Calculating Common Cause; Examples; Defense against Common Cause; Impact of varied Common Cause Failure (CCF) and abortability; Response Surface for various CCF Beta; Takeaways.
Evaluation of ultrafiltration failure.
Korbet, S M
The evaluation of ultrafiltration failure is embarked upon when a patient has persistent problems with symptoms and signs of fluid overload. Fluid overload is a common problem in peritoneal dialysis (PD) patients and the risk of its occurrence increases with time on dialysis. Although often attributed to changes in peritoneal membrane function (membrane failure), there are a number of potential, and frequently more common factors that can contribute to the failure of adequate fluid removal in patients on PD. Many of the causes of ultrafiltration failure may be apparent after an initial informal evaluation. However, if after this the etiology remains unexplained, a systematic approach to the differential diagnosis of this problem can be utilized with the use of the peritoneal equilibration test. Once a diagnosis is confirmed, a logical therapeutic plan can be formulated.
... help you in the future. Follow Your Treatment Plan Treatment can relieve your symptoms and make daily ... or nurse about getting flu and pneumonia vaccines. Plan Ahead If you have heart failure, it's important ...
What Causes Respiratory Failure?
... Conditions Causing Respiratory Failure Figure A shows the location of the lungs, airways, diaphragm, rib cage, pulmonary arteries, brain, and spinal cord ... STATEMENT FOIA NO FEAR ACT OIG CONTACT US ...
JAM-C promotes lymphangiogenesis and nodal metastasis in non-small cell lung cancer.
Hao, SongNan; Yang, YanMei; Liu, Yan; Yang, ShuCai; Wang, Geng; Xiao, JianBing; Liu, HuiDong
This study aims to investigate lymphatic metastasis-related genes in non-small cell lung carcinomas (NSCLC). NSCLC tissue was analyzed for expression of junctional adhesion molecule-C (JAM-C) protein. Our data revealed novel associations between JAM-C overexpression in primary tumors and lymphatic microvessel density (LMVD), lymph node metastasis, and poorer overall survival and recurrence-free survival. We used the highly metastatic human lung adenocarcinoma cell line Anip973 and its parental line AGZY83-a, which has a low metastatic capacity, in vivo and vitro. We found that JAM-C played an important role in different metastasis capacity of lymph node. JAM-C affected tumor growth, LNM, JAM-C, VEGF-C, vasculature, and ERK1/2 phosphorylation (p-ERK1/2). β1 integrin was involved in lymph node metastasis. Moreover, JAM-C knockdown in highly metastatic Anip973 decreased cell migration in scratch-wound assays. The JAM-C knockdown in Anip973 cells and JAM-C cDNA in AGZY83-a cells regulated the vascular endothelial growth factor C (VEGF-C) expression. Immunofluorescence showed that blocked VEGF-C expression in JAM-C shRNA Anip973 cells were restored after JAM-C treatment. JAM-C-induced VEGF-C in JAM-C cDNA AGZY83-a cells was also effectively inhibited by treatment with an antibody specifically against JAM-C. Use of media from Anip973 cells, AGZY83-a, and A549cells lung cancer cells that overexpressed or downregulated JAM-C was demonstrated to affect activity of VEGF-C-induced β1 integrin subunit or ERK activity in human dermal lymphatic endothelial cells (HDLEC) treated with VEGF-C or inhibitory antibody to JAM-C. Overall, these results indicate that JAM-C could mediate metastasis as it contributes to VEGF-C expression in cancer cells. JAM-C affects β1and ERK activation in HDLEC, thus promoting lymphangiogenesis and nodal metastasis. Our findings indicate that JAM-C may be a therapeutic target for preventing and treating lymphatic metastases.
Anatomical Variations in the Sinoatrial Nodal Artery: A Meta-Analysis and Clinical Considerations
Roy, Joyeeta; Ramakrishnan, Piravin Kumar; Hsieh, Wan Chin; Walocha, Jerzy A.; Tomaszewski, Krzysztof A.
Background and Objective The sinoatrial nodal artery (SANa) is a highly variable vessel which supplies blood to the sinoatrial node (SAN). Due to its variability and susceptibility to iatrogenic injury, our study aimed to assess the anatomy of the SANa and determine the prevalence of its anatomical variations. Study Design An extensive search of major electronic databases was performed to identify all articles reporting anatomical data on the SANa. No lower date limit or language restrictions were applied. Anatomical data regarding the artery were extracted and pooled into a meta-analysis. Results Sixty-six studies (n = 21455 hearts) were included in the meta-analysis. The SANa usually arose as a single vessel with a pooled prevalence of 95.5% (95%CI:93.6–96.9). Duplication and triplication of the artery were also observed with pooled prevalence of 4.3% (95%CI:2.8–6.0) and 0.3% (95%CI:0–0.7), respectively. The most common origin of the SANa was from the right coronary artery (RCA), found in 68.0% (95%CI:55.6–68.9) of cases, followed by origin from the left circumflex artery, and origin from the left coronary artery with pooled prevalence of 22.1% (95%CI:15.0–26.2) and 2.7 (95%CI:0.7–5.2), respectively. A retrocaval course of the SANa was the most common course of the artery with a pooled prevalence of 47.1% (95%CI:36.0–55.5). The pooled prevalence of an S-shaped SANa was 7.6% (95%CI:2.9–14.1). Conclusions The SANa is most commonly reported as a single vessel, originating from the RCA, and taking a retrocaval course to reach the SAN. Knowledge of high risk anatomical variants of the SANa, such as an S-shaped artery, must be taken into account by surgeons to prevent iatrogenic injuries. Specifically, interventional or cardiosurgical procedures, such as the Cox maze procedure for atrial fibrillation, open heart surgeries through the right atrium or intraoperative cross-clamping or dissection procedures during mitral valve surgery using the septal
Genesis Failure Investigation Report
NASA Technical Reports Server (NTRS)
Klein, John
The-Genesis mission to collect solar-wind samples and return them to Earth for detailed analysis proceeded successfully for 3.5 years. During reentry on September 8, 2004, a failure in the entry, descent and landing sequence resulted in a crash landing of the Genesis sample return capsule. This document describes the findings of the avionics sub-team that supported the accident investigation of the JPL Failure Review Board.
Rutherford, John D
With increasing maternal age and the presence of comorbid conditions such as hypertension, cardiovascular assessment and monitoring is the responsibility of all clinicians caring for pregnant patients. Furthermore, there are specific conditions, such as mitral stenosis, peripartum cardiomyopathy, and preeclampsia, that can be associated with heart failure and secondary maternal (and fetal) mortality and morbidity. The important causes of heart failure in pregnancy are discussed.
Bellomo, Rinaldo
Acute renal failure (now acute kidney injury) is a common complication of critical illness affecting between 30 and 60% of critically ill patients. The development of a consensus definition (RIFLE--risk, injury, failure, loss, end-stage system) has allowed standardization of reporting and epidemiological work. Multicenter multinational epidemiological studies indicate that sepsis is now the most common cause of acute renal failure in the intensive care unit (ICU) followed by cardiac surgery-associated acute kidney injury. Unfortunately, our understanding of the pathogenesis of acute renal failure in these settings remains limited. Because of such limited understanding, no reproducibly effective therapies have been developed. In addition the diagnosis of acute renal failure still rests upon the detection of changes in serum creatinine, which only occur if more than 50% of glomerular filtration is lost and are often delayed by more than 24 hours. Such diagnostic delays make the implementation of early therapy nearly impossible. In response to these difficulties, there has been a concerted effort to use proteomics to identify novel early biomarkers of acute renal failure. The identification and study of neutrophil gelatinase- associated lipocalin has been an important step in this field. Another area of active interest and investigation relates to the role of intravenous fluid resuscitation and fluid balance. Data from large observational studies and randomized, controlled trials consistently indicate that a positive fluid balance in patients with acute renal failure represents a major independent risk factor for mortality and provides no protection of renal function. The pendulum is clearly swinging away from a fluid-liberal approach to a fluid-conservative approach in these patients. Finally, there is a growing appreciation that acute renal failure may identify patients who are at increased risk of subsequent chronic renal dysfunction and mortality, opening the way
Evidence for 18.6-year lunar nodal drought in Western North America during the past millennium
NASA Astrophysics Data System (ADS)
Currie, Robert G.
Analysis of 38 tree ring chronologies yields evidence for enhanced drought conditions every 18.6 years in the North American interior for the past millenium. Cross spectra between a drought area index and 26 temperature records confirm the analysis of Currie (1979, 1981d) as regards a lunar nodal MN term in these data. Discussion of the MN tidal constituent, which appreciably modulate amplitude and phase of four main constituents (M2, K1, O1, Mf), is presented, and implications for agriculture are surveyed.
Global Performance Characterization of the Three Burn Trans-Earth Injection Maneuver Sequence over the Lunar Nodal Cycle
NASA Technical Reports Server (NTRS)
Williams, Jacob; Davis, Elizabeth C.; Lee, David E.; Condon, Gerald L.; Dawn, Tim
The Orion spacecraft will be required to perform a three-burn trans-Earth injection (TEI) maneuver sequence to return to Earth from low lunar orbit. The origin of this approach lies in the Constellation Program requirements for access to any lunar landing site location combined with anytime lunar departure. This paper documents the development of optimized databases used to rapidly model the performance requirements of the TEI three-burn sequence for an extremely large number of mission cases. It also discusses performance results for lunar departures covering a complete 18.6 year lunar nodal cycle as well as general characteristics of the optimized three-burn TEI sequence.
An incidental finding of a nodal recurrence of cutaneous malignant melanoma after a 45-year disease-free period.
Goodenough, Jenny; Cozon, Caroline Louise; Liew, Se Hwang
We report the case of an 84-year-old woman who had a nodal recurrence of melanoma 45 years after the primary diagnosis of an extremity cutaneous melanoma. It is believed to be the longest disease-free latency period reported between primary melanoma diagnosis and recurrence to date. Late recurrences of melanoma are rare and recurrence after four decades extremely rare. This article suggests melanoma is a disease with a potentially lifelong risk of recurrence and thus clinicians and patients must be vigilant and aware of this risk, particularly if late recurrences are to be recognised early and management optimised.
Mangini, Sandrigo; Pires, Philippe Vieira; Braga, Fabiana Goulart Marcondes; Bacal, Fernando
ABSTRACT Heart failure is a disease with high incidence and prevalence in the population. The costs with hospitalization for decompensated heart failure reach approximately 60% of the total cost with heart failure treatment, and mortality during hospitalization varies according to the studied population, and could achieve values of 10%. In patients with decompensated heart failure, history and physical examination are of great value for the diagnosis of the syndrome, and also can help the physician to identify the beginning of symptoms, and give information about etiology, causes and prognosis of the disease. The initial objective of decompensated heart failure treatment is the hemodynamic and symptomatic improvement preservation and/or improvement of renal function, prevention of myocardial damage, modulation of the neurohormonal and/or inflammatory activation and control of comorbidities that can cause or contribute to progression of the syndrome. According to the clinical-hemodynamic profile, it is possible to establish a rational for the treatment of decompensated heart failure, individualizing the proceedings to be held, leading to reduction in the period of hospitalization and consequently reducing overall mortality. PMID:24136770
Kalantaridou, S N; Davis, S R; Nelson, L M
In 1% of women, premature ovarian failure develops by 40 years of age, a condition causing amenorrhea, infertility, sex steroid deficiency, and elevated gonadotropins. Early loss of ovarian function has significant psychosocial sequelae and major health implications. These young women have a nearly two-fold age-specific increase in mortality rate. Among women with spontaneous premature ovarian failure who have a normal karyotype, half have ovarian follicles remaining in the ovary that function intermittently. Indeed, pregnancies have occurred after the diagnosis of premature ovarian failure. Thus, premature ovarian failure should not be considered as a premature menopause. Young women with this disorder have a 5% to 10% chance for spontaneous pregnancy. Attempts at ovulation induction using various regimens fail to induce ovulation rates greater than those seen in untreated patients; however, oocyte donation for women desiring fertility is an option. Young women with premature ovarian failure need a thorough assessment, sex steroid replacement, and long-term surveillance to monitor therapy. Estrogen-progestin replacement therapy should be instituted as soon as the diagnosis is made. Androgen replacement should also be considered for women with low libido, persistent fatigue, and poor well-being despite taking adequate estrogen replacement. Women with premature ovarian failure should be followed up for the presence of associated autoimmune endocrine disorders such as hypothyroidism, adrenal insufficiency, and diabetes mellitus.
A clinical series and literature review of the management of inguinal nodal metastases in patients with primary extramammary Paget disease of the scrotum.
Koh, Ye Xin; Tay, Timothy Kwang Yong; Xu, Sheng; Lee, Chee Meng; Teo, Melissa Ching Ching
We describe a series of five patients with extramammary Paget disease of the scrotum with inguinal nodal metastases. These patients underwent combined groin dissection. All patients experienced invasion to the dermis. One patient had invasion of the dartos muscle, another had tumor invading into the skeletal muscle and femoral vein. Four patients had positive Cloquet node involvement on frozen section and formal histology, but only one patient had positive pelvic nodal disease. Another patient with pelvic nodal metastases seen on computed tomography scan had no Cloquet node identified intraoperatively but had positive pelvic nodal metastases. The mean disease-free survival and the overall survival were 28.6 months (range: 2-60 months) and 33.4 months (range: 2-60 months), respectively, for all patients. Three patients developed distant metastases and two patients were disease free to date. No locoregional recurrences were observed. Aggressive lymphadenectomy in selected cases can provide a long-term survival benefit. The use of Cloquet node in the prediction of pelvic nodal disease should be considered. Based on the literature review, sentinel lymph node biopsy can potentially diagnose occult metastases in otherwise nonenlarged nodes.
NASA Technical Reports Server (NTRS)
Hark, Frank; Britton, Paul; Ring, Rob; Novack, Steven D.
Common Cause Failures (CCFs) are a known and documented phenomenon that defeats system redundancy. CCFS are a set of dependent type of failures that can be caused by: system environments; manufacturing; transportation; storage; maintenance; and assembly, as examples. Since there are many factors that contribute to CCFs, the effects can be reduced, but they are difficult to eliminate entirely. Furthermore, failure databases sometimes fail to differentiate between independent and CCF (dependent) failure and data is limited, especially for launch vehicles. The Probabilistic Risk Assessment (PRA) of NASA's Safety and Mission Assurance Directorate at Marshall Space Flight Center (MFSC) is using generic data from the Nuclear Regulatory Commission's database of common cause failures at nuclear power plants to estimate CCF due to the lack of a more appropriate data source. There remains uncertainty in the actual magnitude of the common cause risk estimates for different systems at this stage of the design. Given the limited data about launch vehicle CCF and that launch vehicles are a highly redundant system by design, it is important to make design decisions to account for a range of values for independent and CCFs. When investigating the design of the one-out-of-two component redundant system for launch vehicles, a response surface was constructed to represent the impact of the independent failure rate versus a common cause beta factor effect on a system's failure probability. This presentation will define a CCF and review estimation calculations. It gives a summary of reduction methodologies and a review of examples of historical CCFs. Finally, it presents the response surface and discusses the results of the different CCFs on the reliability of a one-out-of-two system.
NASA Technical Reports Server (NTRS)
Hark, Frank; Britton, Paul; Ring, Rob; Novack, Steven D.
Common Cause Failures (CCFs) are a known and documented phenomenon that defeats system redundancy. CCFS are a set of dependent type of failures that can be caused by: system environments; manufacturing; transportation; storage; maintenance; and assembly, as examples. Since there are many factors that contribute to CCFs, the effects can be reduced, but they are difficult to eliminate entirely. Furthermore, failure databases sometimes fail to differentiate between independent and CCF (dependent) failure and data is limited, especially for launch vehicles. The Probabilistic Risk Assessment (PRA) of NASA's Safety and Mission Assurance Directorate at Marshal Space Flight Center (MFSC) is using generic data from the Nuclear Regulatory Commission's database of common cause failures at nuclear power plants to estimate CCF due to the lack of a more appropriate data source. There remains uncertainty in the actual magnitude of the common cause risk estimates for different systems at this stage of the design. Given the limited data about launch vehicle CCF and that launch vehicles are a highly redundant system by design, it is important to make design decisions to account for a range of values for independent and CCFs. When investigating the design of the one-out-of-two component redundant system for launch vehicles, a response surface was constructed to represent the impact of the independent failure rate versus a common cause beta factor effect on a system's failure probability. This presentation will define a CCF and review estimation calculations. It gives a summary of reduction methodologies and a review of examples of historical CCFs. Finally, it presents the response surface and discusses the results of the different CCFs on the reliability of a one-out-of-two system.
An Improved Micropropagation Protocol by Ex Vitro Rooting of Passiflora edulis Sims. f. flavicarpa Deg. through Nodal Segment Culture
Shekhawat, Mahipal S.; Manokari, M.; Ravindran, C. P.
A procedure for rapid clonal propagation of Passiflora edulis Sims. f. flavicarpa Deg. (Passifloraceae) has been developed in this study. Nodal explants were sterilized with 0.1% HgCl2 and inoculated on Murashige and Skoog (MS) basal medium. The addition of 2.0 mgL−1 6-benzylaminopurine (BAP) to MS medium caused an extensive proliferation of multiple shoots (8.21 ± 1.13) primordial from the nodal meristems. Subculturing of these multiple shoots on the MS medium augmented with 1.0 mgL−1 of each BAP and Kinetin (Kin) was successful for the multiplication of the shoots in vitro with maximum numbers of shoots (25.73 ± 0.06) within four weeks of incubation. Shoots were rooted best (7.13 ± 0.56 roots/shoots) on half strength MS medium supplemented with 2.0 mgL−1 indole-3 butyric acid (IBA). All in vitro regenerated shoots were rooted by ex vitro method, and this has achieved 6-7 roots per shoot by pulsing of cut ends of the shoots using 200 as well as 300 mgL−1 IBA. The plantlets were hardened in the greenhouse for 4-5 weeks. The hardened plantlets were shifted to manure containing nursery polybags after five weeks and then transferred to a sand bed for another four weeks for acclimatization before field planting with 88% survival rate. PMID:26273489
Expression of the polycomb‐group gene BMI1 is related to an unfavourable prognosis in primary nodal DLBCL
van Galen, Joost C; Muris, Jettie J F; Oudejans, Joost J; Vos, Wim; Giroth, Cindy P E; Ossenkoppele, Gert J; Otte, Arie P; Raaphorst, Frank M; Meijer, Chris J L M
Background Clinical outcome in patients with diffuse large B cell lymphomas (DLBCL) is highly variable and poorly predictable. Microarray studies showed that patients with DLBCL with a germinal centre B cell‐like (GCB) phenotype have a better prognosis than those with an activated B cell‐like (ABC) phenotype. The BMI1 proto‐oncogene was identified as one of the genes present in the signature of the ABC type of DLBCL, associated with a poor prognosis. Objectives (1) To investigate, in primary nodal DLBCL, the expression of BMI1 and its association with clinical outcome and DLBCL signature; (2) to look for an association between BMI1 expression and the expression of its putative downstream targets p14ARF and p16INK4a. Results BMI1 expression was found to be associated with poor clinical outcome, but not clearly with an ABC‐like phenotype of DLBCL. Expression of BMI1 was frequently, but not always, related to low levels of expression of p14ARF and p16INK4a. Conclusion Expression of BMI1 is associated with an unfavourable clinical outcome of primary nodal DLBCL. PMID:16837630
Nodal bilayer-splitting controlled by spin-orbit interactions in underdoped high-Tc cuprates
Harrison, N.; Ramshaw, B. J.; Shekhter, A.
The highest superconducting transition temperatures in the cuprates are achieved in bilayer and trilayer systems, highlighting the importance of interlayer interactions for high Tc. It has been argued that interlayer hybridization vanishes along the nodal directions by way of a specific pattern of orbital overlap. Recent quantum oscillation measurements in bilayer cuprates have provided evidence for a residual bilayer-splitting at the nodes that is sufficiently small to enable magnetic breakdown tunneling at the nodes. Here we show that several key features of the experimental data can be understood in terms of weak spin-orbit interactions naturally present in bilayer systems, whose primary effect is to cause the magnetic breakdown to be accompanied by a spin flip. These features can now be understood to include the equidistant set of three quantum oscillation frequencies, the asymmetry of the quantum oscillation amplitudes in c-axis transport compared to ab-plane transport, and the anomalous magnetic field angle dependence of the amplitude of the side frequencies suggestive of small effective g-factors. We suggest that spin-orbit interactions in bilayer systems can further affect the structure of the nodal quasiparticle spectrum in the superconducting phase. PACS numbers: 71.45.Lr, 71.20.Ps, 71.18.+y
Computation of astigmatic and trefoil figure errors and misalignments for two-mirror telescopes using nodal-aberration theory.
Ju, Guohao; Yan, Changxiang; Gu, Zhiyuan; Ma, Hongcai
In active optics systems, one concern is how to quantitatively separate the effects of astigmatic and trefoil figure errors and misalignments that couple together in determining the total aberration fields when wavefront measurements are available at only a few field points. In this paper, we first quantitatively describe the impact of mount-induced trefoil deformation on the net aberration fields by proposing a modified theoretical formulation for the field-dependent aberration behavior of freeform surfaces based on the framework of nodal aberration theory. This formulation explicitly expresses the quantitative relationships between the magnitude of freeform surfaces and the induced aberration components where the freeform surfaces can be located away from the aperture stop and decentered from the optical axis. On this basis, and in combination with the mathematical presentation of nodal aberration theory for the effects of misalignments, we present the analytic expressions for the aberration fields of two-mirror telescopes in the presence of astigmatic primary mirror figure errors, mount-induced trefoil deformations on both mirrors, and misalignments. We quantitatively separate these effects using the analytical expressions with wavefront measurements at a few field points and pointing errors. Valuable insights are provided on how to separate these coupled effects in the computation process. Monte Carlo simulations are conducted to demonstrate the correctness and accuracy of the analytic method presented in this paper.
Enhanced A-V nodal conduction (Lown-Ganong-Levine syndrome) by congenitally hypoplastic A-V node.
Ometto, R; Thiene, G; Corrado, D; Vincenzi, M; Rossi, L
The basic anatomical substrate of enhanced A-V nodal conduction, manifesting or not as Lown-Ganong-Levine syndrome, is still a controversial issue. We describe the case of a 34-year-old man who presented episodes of ventricular fibrillation. Electrophysiological studies showed that the AH interval was 55 ms, and increased by only 20 ms at paced cycle lengths of 300 ms; atrial pacing induced atrial fibrillation, with a shortest RR interval of 240 ms. Despite verapamil therapy, this patient died suddenly at home. Histological study disclosed a severe A-V node hypoplasia that was evidently congenital in nature; the rest of the conduction system was normal, and no accessory A-V pathways were present. We suggest that enhanced A-V nodal conduction in this patient was due to the developmental defect in the A-V node; this abnormality caused a loss of specific impulse-delaying function, and thus allowed rapid, unfiltered atrial impulses to reach the lower A-V junction and ventricles.
J-integral evaluation for 2D mixed-mode crack problems employing a meshfree stabilized conforming nodal integration method
NASA Astrophysics Data System (ADS)
Tanaka, Satoyuki; Suzuki, Hirotaka; Sadamoto, Shota; Sannomaru, Shogo; Yu, Tiantang; Bui, Tinh Quoc
Two-dimensional (2D) in-plane mixed-mode fracture mechanics problems are analyzed employing an efficient meshfree Galerkin method based on stabilized conforming nodal integration (SCNI). In this setting, the reproducing kernel function as meshfree interpolant is taken, while employing the SCNI for numerical integration of stiffness matrix in the Galerkin formulation. The strain components are smoothed and stabilized employing Gauss divergence theorem. The path-independent integral ( J-integral) is solved based on the nodal integration by summing the smoothed physical quantities and the segments of the contour integrals. In addition, mixed-mode stress intensity factors (SIFs) are extracted from the J-integral by decomposing the displacement and stress fields into symmetric and antisymmetric parts. The advantages and features of the present formulation and discretization in evaluation of the J-integral of in-plane 2D fracture problems are demonstrated through several representative numerical examples. The mixed-mode SIFs are evaluated and compared with reference solutions. The obtained results reveal high accuracy and good performance of the proposed meshfree method in the analysis of 2D fracture problems.
The Nicastrin-like protein Nicalin regulates assembly and stability of the Nicalin-nodal modulator (NOMO) membrane protein complex.
Haffner, Christof; Dettmer, Ulf; Weiler, Timotheus; Haass, Christian
The assembly of the gamma-secretase complex, an Alzheimer disease-related protease required for beta-amyloid generation, is tightly regulated and predominantly limited by the stoichiometrical availability of its components. We have identified a novel endoplasmic reticulum-located protein complex that is regulated in a similar fashion. It contains the recently identified Nodal signaling antagonists Nicalin (a distant homolog of the gamma-secretase component Nicastrin) and NOMO (Nodal modulator). Using an RNA interference approach, we found that Nicalin and NOMO became unstable in the absence of the respective binding partner, suggesting that complex formation has a stabilizing effect. Overexpression of Nicalin resulted in an increase in NOMO, whereas endogenous Nicalin was reduced below the detection limit. Both effects were shown to occur at a post-transcriptional level. Thus, NOMO is most likely produced in excess amounts and either stabilized by Nicalin or rapidly degraded. In contrast, Nicalin levels are limited independently of NOMO. We, therefore, propose that Nicalin controls the assembly and stability of the Nicalin-NOMO complex.
A three-dimensional definition of nodal spaces on the basis of CT images showing enlarged nodes for pelvic radiotherapy
Portaluri, Maurizio . E-mail: firstname.lastname@example.com; Bambace, Santa; Perez, Celeste; Angone, Grazia
Purpose: To demonstrate that margins of each pelvic chain may be derived by verifying the bony and soft tissue structures around abnormal nodes on computed tomography (CT) slices. Methods and Materials: Twenty consecutive patients (16 males, 4 females; mean age, 66 years; range, 43-80 years) with radiologic diagnosis of nodal involvement by histologically proved cervix carcinoma (two), rectum carcinoma (three), prostate carcinoma (four), lymphoma (five), penis carcinoma (one), corpus uteri carcinoma (one), bladder carcinoma (two), cutis tumor (one), and soft-tissue sarcoma (one) were retrospectively reviewed. One hundred CT scans showing 85 enlarged pelvic nodes were reviewed by two radiation oncologists (M.P., S.B.), and two radiologists (C.P., G.A.). Results: The more proximal structures to each enlarged node or group of nodes were thus recorded in a clockwise direction. Conclusion: According to their frequency and visibility, craniocaudal, anterior, lateral, posterior and medial margins of common iliac, external and internal iliac nodal chains, obturator and pudendal nodes, and deep and superficial inguinal nodes were derived from CT observations.
Technology integration box beam failure study
NASA Technical Reports Server (NTRS)
Shuart, M. J.; Ambur, Damodar R.; Davis, D. D., Jr.; Davis, R. C.; Farley, G. L.; Lotts, C. G.; Wang, J. T.
Composite structures have the potential to be cost-effective, structurally efficient primary aircraft structures. The Advanced Composites Technology (ACT) Program has the goal to develop the technology to exploit this potential for heavily loaded aircraft structures. As part of the ACT Program, Lockheed Aeronautical Systems Company completed the design and fabrication of the Technology Integration Box Beam (TIBB). The TIBB is an advanced composite prototype structure for the center wing section of the C-130 aircraft. Lockheed subjected the TIBB to downbending, upbending, torsion and combined upbending and torsion load conditions to verify the design. The TIBB failed at 83 percent of design ultimate load for the combined upbending and torsion load condition. The objective of this paper is to describe the mechanisms that led to the failure of the TIBB. The results of a comprehensive analytical and experimental study are presented. Analytical results include strain and deflection results from both a global analysis of the TIBB and a local analysis of the failure region. These analytical results are validated by experimental results from the TIBB tests. The analytical and experimental results from the TIBB tests are used to determine a sequence of events that resulted in failure of the TIBB. A potential cause of failure is high stresses in a stiffener runout region. Analytical and experimental results are also presented for a stiffener runout specimen that was used to simulate the TIBB failure mechanisms.
Reda, S; Motloch, L J; Hoppe, U C
Chronic heart failure has an age-dependent prevalence of 2% and is therefore one of the most frequent diseases in western societies. A reduced hemoglobin concentration according to the definition of the World Health Organization is a common comorbidity affecting more than half of all heart failure patients. Elderly patients, patients suffering from renal impairment and women are more likely to develop anemia but a definitive etiology of anemia is only identified in the minority of cases. Anemia is associated with a poor clinical status and a greater risk of hospitalization and is a predictive factor for increased mortality. The incidence of anemia appears to increase with a poorer functional class. Intravenous iron therapy improves the exercise capacity in patients with systolic heart failure and iron deficiency and is currently being recommended for patients with persistent symptoms despite optimal medical and device therapy. However, erythropoietin-stimulating agents as a treatment for anemia in chronic heart failure have failed to improve clinical outcome in a large randomized trial. In patients with heart failure but with maintained ejection fraction, anemia is also associated with a poor prognosis. Specific therapeutic recommendations for these patients are still not available.
Opening a nodal gap by fluctuating spin-density wave in lightly doped La2 -xSrxCuO4
NASA Astrophysics Data System (ADS)
Kapon, Itzik; Ellis, David S.; Drachuck, Gil; Bazalitski, Galina; Weschke, Eugen; Schierle, Enrico; Strempfer, Jörg; Niedermayer, Christof; Keren, Amit
We investigate whether the spin or charge degrees of freedom are responsible for the nodal gap in underdoped cuprates by performing inelastic neutron scattering and x-ray diffraction measurements on La2 -xSrxCuO4 , which is on the edge of the antiferromagnetic phase. We found that a fluctuating incommensurate spin-density wave (SDW) with a bottom part of an hourglass dispersion exists even in this magnetic sample. The strongest component of these fluctuations diminishes at the same temperature where the nodal gap opens. X-ray scattering measurements on the same crystal show no signature of a charge-density wave (CDW). Therefore, we suggest that the nodal gap in the electronic band of this cuprate opens due to fluctuating SDW with no contribution from CDW.
Congenital subclavian arteriovenous malformation causing cardiac failure in an adult.
Anoop, T M; Sreejith, P; Thomas, Joby K; Gailin, B; Jabbar, P K; Ittycheria, Cherian C; George, Raju
Congenital arteriovenous malformations (AVMs) of the thoracic region are rarely reported in adults. The authors report an unusual case of a 30-year-old man who presented with a large congenital AVM and heart failure. The diagnosis was made using transthoracic Doppler echocardiography and computed tomography. Embolization followed by surgical resection of the AVM resulted in the prompt relief of heart failure.
Pennell, William E.; Sutton, Jr., Harry G.
Method and apparatus for detecting failure in a welded connection, particrly applicable to not readily accessible welds such as those joining components within the reactor vessel of a nuclear reactor system. A preselected tag gas is sealed within a chamber which extends through selected portions of the base metal and weld deposit. In the event of a failure, such as development of a crack extending from the chamber to an outer surface, the tag gas is released. The environment about the welded area is directed to an analyzer which, in the event of presence of the tag gas, evidences the failure. A trigger gas can be included with the tag gas to actuate the analyzer.
Vormelker, P
Two high-pressure bioassay vessels failed at the Savannah River Site during a microwave heating process for biosample testing. Improper installation of the thermal shield in the first failure caused the vessel to burst during microwave heating. The second vessel failure is attributed to overpressurization during a test run. Vessel failure appeared to initiate in the mold parting line, the thinnest cross-section of the octagonal vessel. No material flaws were found in the vessel that would impair its structural performance. Content weight should be minimized to reduce operating temperature and pressure. Outer vessel life is dependent on actual temperature exposure. Since thermal aging of the vessels can be detrimental to their performance, it was recommended that the vessels be used for a limited number of cycles to be determined by additional testing.
Heart Failure in Sub-Saharan Africa
Bloomfield, Gerald S; Barasa, Felix A; Doll, Jacob A; Velazquez, Eric J
The heart failure syndrome has been recognized as a significant contributor to cardiovascular disease burden in sub-Saharan African for many decades. Seminal knowledge regarding heart failure in the region came from case reports and case series of the early 20th century which identified infectious, nutritional and idiopathic causes as the most common. With increasing urbanization, changes in lifestyle habits, and ageing of the population, the spectrum of causes of HF has also expanded resulting in a significant burden of both communicable and non-communicable etiologies. Heart failure in sub-Saharan Africa is notable for the range of etiologies that concurrently exist as well as the healthcare environment marked by limited resources, weak national healthcare systems and a paucity of national level data on disease trends. With the recent publication of the first and largest multinational prospective registry of acute heart failure in sub-Saharan Africa, it is timely to review the state of knowledge to date and describe the myriad forms of heart failure in the region. This review discusses several forms of heart failure that are common in sub-Saharan Africa (e.g., rheumatic heart disease, hypertensive heart disease, pericardial disease, various dilated cardiomyopathies, HIV cardiomyopathy, hypertrophic cardiomyopathy, endomyocardial fibrosis, ischemic heart disease, cor pulmonale) and presents each form with regard to epidemiology, natural history, clinical characteristics, diagnostic considerations and therapies. Areas and approaches to fill the remaining gaps in knowledge are also offered herein highlighting the need for research that is driven by regional disease burden and needs. PMID:23597299
Scott, Michael C; Winters, Michael E
Patients with acute decompensated heart failure are usually critically ill and require immediate treatment. However, most are not volume overloaded. Emergency department (ED) management is based on rapid initiation of noninvasive positive-pressure ventilation and aggressive titration of nitrates. Afterload reduction with an angiotensin-converting enzyme inhibitor can be considered. A diuretic should not be administered before optimal preload and afterload reduction has been achieved. Short-term inotropic therapy can be considered in select patients with cardiogenic shock and acute decompensated heart failure (ADHF) who fail to respond to standard therapy.
Failure detection and identification
NASA Technical Reports Server (NTRS)
Massoumnia, Mohammad-Ali; Verghese, George C.; Willsky, Alan S.
Using the geometric concept of an unobservability subspace, a solution is given to the problem of detecting and identifying control system component failures in linear, time-invariant systems. Conditions are developed for the existence of a causal, linear, time-invariant processor that can detect and uniquely identify a component failure, first for the case where components can fail simultaneously, and then for the case where they fail only one at a time. Explicit design algorithms are provided when these conditions are satisfied. In addition to time-domain solvability conditions, frequency-domain interpretations of the results are given, and connections are drawn with results already available in the literature.
NASA Technical Reports Server (NTRS)
Wetherholt, Jon; Heimann, Timothy J.; Anderson, Brenda
High technology industries with high failure costs commonly use redundancy as a means to reduce risk. Redundant systems, whether similar or dissimilar, are susceptible to Common Cause Failures (CCF). CCF is not always considered in the design effort and, therefore, can be a major threat to success. There are several aspects to CCF which must be understood to perform an analysis which will find hidden issues that may negate redundancy. This paper will provide definition, types, a list of possible causes and some examples of CCF. Requirements and designs from NASA projects will be used in the paper as examples.
Hypothyroid acute renal failure.
Birewar, Sonali; Oppenheimer, Mark; Zawada, Edward T
Muscular disorders and even hypothyroid myopathy with elevated muscle enzymes are commonly seen in hypothyroidism. In this paper, we report a case of acute renal failure in a 35-year old male patient with myalgia. His serum creatinine reached a level of 2.4 mg/dl. Later, his myalgia was found to be due to hypothyroidism with TSH of over 500 uiv/ml. With thyroid replacement therapy, myalgia and his serum creatinine stabilized and subsequently improved. Hypothyroidism, although rare, has been reported as a definite and authentic cause of rhabdomyolysis. As a result, hypothyroidism must be considered in patients presenting with acute renal failure and elevated muscle enzymes.
Dimension limit for thermal shock failure
NASA Astrophysics Data System (ADS)
Shao, Y. F.; Liu, Q. N.; Tian, H. J.; Lin, Z. K.; Xu, X. H.; Song, F.
We analytically present the characteristic dimensional limit below which the thermal shock failure of ceramics never occurs. This limit, together with the critical temperature difference, separates the state space of the ceramics under thermal shock into two parts - the cracked and the uncracked. Based on the water-quench tests of ceramics, we experimentally proved that when the states of ceramics are in the uncracked region, the ceramics do not produce any cracks during thermal shock. The results provide a guide to prevent thermal shock failure in ceramic.
Role of HSP101 in the stimulation of nodal root development from the coleoptilar node by light and temperature in maize (Zea mays L.) seedlings
López-Frías, Guillermo; Martínez, Luz María; Ponce, Georgina; Cassab, Gladys I.; Nieto-Sotelo, Jorge
Nodal roots (NRs) constitute the prevalent root system of adult maize plants. NRs emerge from stem nodes located below or above ground, and little is known about their inducing factors. Here, it is shown that precocious development of NRs at the coleoptilar node (NRCNs) occurred in maize seedlings when: (i) dark grown and stimulated by the concurrent action of a single light shock of low intensity white light (2 μmol m−2 s−1) and a single heat shock; (ii) grown under a photoperiod of low intensity light (0.1 μmol m−2 s−1); or (iii) grown in the dark under a thermoperiod (28 °C/34 °C). The light shock effects were synergistic with heat shock and with the photoperiod, whereas the thermoperiodical and photoperiodical effects were additive. Dissection of the primary root or the root cap, to mimic the fatal consequences of severe heat shock, caused negligible effects on NRCN formation, indicating that the shoot is directly involved in perception of the heat shock-inducible signal that triggered NRCN formation. A comparison between hsp101-m5::Mu1/hsp101-m5::Mu1 and Hsp101/Hsp101 seedlings indicated that the heat shock protein 101 (HSP101) chaperone inhibited NRCN formation in the light and in the dark. Stimulation of precocious NRCN formation by light and heat shocks was affected by genetic background and by the stage of seedling development. HSP101 protein levels increased in the coleoptilar node of induced wild-type plants, particularly in the procambial region, where NRCN formation originated. The adaptive relevance of development of NRCNs in response to these environmental cues and hypothetical mechanisms of regulation by HSP101 are discussed. PMID:21652530
Role of HSP101 in the stimulation of nodal root development from the coleoptilar node by light and temperature in maize (Zea mays L.) seedlings.
López-Frías, Guillermo; Martínez, Luz María; Ponce, Georgina; Cassab, Gladys I; Nieto-Sotelo, Jorge
Nodal roots (NRs) constitute the prevalent root system of adult maize plants. NRs emerge from stem nodes located below or above ground, and little is known about their inducing factors. Here, it is shown that precocious development of NRs at the coleoptilar node (NRCNs) occurred in maize seedlings when: (i) dark grown and stimulated by the concurrent action of a single light shock of low intensity white light (2 μmol m(-2) s(-1)) and a single heat shock; (ii) grown under a photoperiod of low intensity light (0.1 μmol m(-2) s(-1)); or (iii) grown in the dark under a thermoperiod (28 °C/34 °C). The light shock effects were synergistic with heat shock and with the photoperiod, whereas the thermoperiodical and photoperiodical effects were additive. Dissection of the primary root or the root cap, to mimic the fatal consequences of severe heat shock, caused negligible effects on NRCN formation, indicating that the shoot is directly involved in perception of the heat shock-inducible signal that triggered NRCN formation. A comparison between hsp101-m5::Mu1/hsp101-m5::Mu1 and Hsp101/Hsp101 seedlings indicated that the heat shock protein 101 (HSP101) chaperone inhibited NRCN formation in the light and in the dark. Stimulation of precocious NRCN formation by light and heat shocks was affected by genetic background and by the stage of seedling development. HSP101 protein levels increased in the coleoptilar node of induced wild-type plants, particularly in the procambial region, where NRCN formation originated. The adaptive relevance of development of NRCNs in response to these environmental cues and hypothetical mechanisms of regulation by HSP101 are discussed.
On the failure and post-failure of fiber composites in compression
NASA Astrophysics Data System (ADS)
Vogler, Tracy John
The failure and post-failure behavior of an AS4/PEEK composite in axial compression was studied through experiments and analysis. Compressive stresses cause shearing of the matrix in regions of fiber misaligned. Increasing stresses yield the matrix, resulting in fiber collapse and failure of the composite. The strength is strongly imperfection sensitive. After failure, deformation localizes into an inclined region of rotated fibers called a kink band. Compressive failure was investigated using 2-D and 3-D finite element models and three simpler models. When properly calibrated, their strength predictions are quite similar, especially for larger fiber misalignments. However, the FE models allow examination of post-failure events leading to kink band formation. The rate dependence of compressive strength was examined experimentally and with a modified version of a simple model. The addition of a far-field shear stress significantly reduces the compressive strength. Failure predictions from modified versions of the 2-D model and the simple models agree well with experimental data. Post-failure events are very similar to those observed for pure compression loading, except that failure can occur in a controlled manner for certain loading paths. It has been discovered that the kink bands formed during compressive failure can propagate axially in a steady-state manner at a constant stress level termed the propagation stress. This propagation stress, a new characteristic stress of the material, is approximately 40% of the compressive strength for AS4/PEEK. Steadystate propagation can give "ductility" to a material normally considered quite brittle. The propagation has been observed directly, revealing the mechanism of propagation as well as new details about fiber rotation in the band. A 3-D numerical model was developed which simulates the steady-state propagation. The propagation stress and deformation are predicted reasonably well. As a basis for modeling of failure and
Preventing Early Learning Failure.
ERIC Educational Resources Information Center
Sornson, Bob, Ed.
Noting that thousands of young children with the capacity to experience school success do not because they are unprepared for school learning activities, have experienced physical or emotional setbacks that cause them to be at risk for early learning failure, have never experienced limits on their behavior, or have mild sensory or motor deficits,…
ERIC Educational Resources Information Center
Saffran, Murray
Describes mistakes made in trying to change the Nutrition and Digestion section of a medical biochemistry course. Author tried to make the section student taught and reports nine mistakes including the following: ignoring active opposition of colleagues, failure to assess the receptivity of the class to a new form of teaching, and overestimating…
... the ureter (s) or a tube connected to an external drainage bag. Both options are used to unblock the ureters in order to allow proper urine flow from the kidneys if this has been identified as the cause for the renal failure. Surgical treatment such as a urinary stent or ...
Knarr, C.M.; Barker, T.J.; McKenery, S.F. )
This article describes efforts by Southern California Edison to meet Federal Energy Regulatory Commission requirements for unattended dam monitoring against failure. The topics include a description of the two dam systems, monitoring system design and operation including warning sirens for remote camping areas, and installation of the systems.
ERIC Educational Resources Information Center
Carpenter, Peter
In this article, it is argued that Kurt Hahn felt that it was important for children to experience 'failure' at times and to learn how to cope with it. If this is no longer desirable in the classroom, it ought to be possible to encourage children to be adventurous and "take risks" in a wide range of Outward Bound activities.
Reliability assessment on interfacial failure of thermal barrier coatings
NASA Astrophysics Data System (ADS)
Guo, Jin-Wei; Yang, Li; Zhou, Yi-Chun; He, Li-Min; Zhu, Wang; Cai, Can-Ying; Lu, Chun-Sheng
Thermal barrier coatings (TBCs) usually exhibit an uncertain lifetime owing to their scattering mechanical properties and severe service conditions. To consider these uncertainties, a reliability assessment method is proposed based on failure probability analysis. First, a limit state equation is established to demarcate the boundary between failure and safe regions, and then the failure probability is calculated by the integration of a probability density function in the failure area according to the first- or second-order moment. It is shown that the parameters related to interfacial failure follow a Weibull distribution in two types of TBC. The interfacial failure of TBCs is significantly affected by the thermal mismatch of material properties and the temperature drop in service.
Enhanced Schapery Theory Software Development for Modeling Failure of Fiber-Reinforced Laminates
NASA Technical Reports Server (NTRS)
Pineda, Evan J.; Waas, Anthony M.
. The ISV evolution equations are derived in a thermodynamically consistent manner by invoking the stationary principle on the total work of the system with respect to each ISV. A novel feature is the inclusion of both pre-peak damage and appropriately scaled, post-peak strain softening failure. Also, the characteristic elements used in the failure degradation scheme are calculated using the element nodal coordinates, rather than simply the square root of the area of the element.
Dynamic failure in brittle solids
Grady, D.E.
Failure of brittle solids within the extremes of the shock loading environment is not well understood. Recent shock-wave data on compression shear failure and tensile spall failure for selected high-strength ceramics are presented and used to examine the mechanisms of dynamic failure. Energy-based theories are used to bound the measured strength properties. A new concept of failure waves in brittle solids is explored in light of the kinetic processes of high-rate fracture. Classical failure criteria are compared with the present base of dynamic strength data on ceramics.
Intensive Care of a Weil's Disease With Multiorgan Failure
Togal, Turkan; Sener, Ali; Yucel, Neslihan; Demirbilek, Semra; Akgun, Feride Sinem; Aydogan, Mustafa; Ucar, Muharrem; Ersoy, M. Ozcan
Leptospirosis is a commonly encountered type of zoonosis, especially in tropical regions. There is insufficient data regarding its frequency in non-tropical regions such as Turkey. Although leptospirosis presents with a mild icteric form in nearly 90% of cases, it can lead to Weils disease characterized by fever as well as fulminant hepatorenal and respiratory failure, in approximately 5 - 10% of cases. In this case report, we present a patient with Weil's disease, complicated with multiorgan failure. Keywords Weil's disease; Leptospirosis; Multiorgan failure PMID:21629529
Childhood nodal marginal zone lymphoma with unusual clinicopathologic and cytogenetic features for the pediatric variant: a case report.
Aqil, Barina; Merritt, Brian Y; Elghetany, M Tarek; Kamdar, Kala Y; Lu, Xinyan Y; Curry, Choladda V
Nodal marginal zone lymphoma (NMZL) is a B-cell lymphoma that shares morphologic and immunophenotypic features with extranodal and splenic marginal zone lymphomas but lacks extranodal or splenic involvement at presentation. NMZL occurs mostly in adults with no sex predilection, at advanced stage (III or IV), with frequent relapses and a high incidence of tumoral genetic abnormalities including trisomies 3 and 18 and gain of 7q. Pediatric NMZL, however, is a rare but distinct variant of NMZL with characteristic features including male predominance, asymptomatic and localized (stage I) disease, low relapse rates with excellent outcomes, and a lower incidence of essentially similar genetic aberrations compared to adult NMZL. Here we describe a unique case of childhood NMZL with unusual clinicopathologic features for the pediatric variant including generalized lymphadenopathy, high-stage disease with persistence after therapy, unusual immunophenotype (CD5, CD23, and BCL6 positive), and unique chromosomal abnormalities including monosomy 20 and add(10)(p11.2).
Strain-induced nonsymmorphic symmetry breaking and removal of Dirac semimetallic nodal line in an orthoperovskite iridate
NASA Astrophysics Data System (ADS)
Liu, Jian; Kriegner, D.; Horak, L.; Puggioni, D.; Rayan Serrao, C.; Chen, R.; Yi, D.; Frontera, C.; Holy, V.; Vishwanath, A.; Rondinelli, J. M.; Marti, X.; Ramesh, R.
By using a combination of heteroepitaxial growth, structure refinement based on synchrotron x-ray diffraction, and first-principles calculations, we show that the symmetry-protected Dirac line nodes in the topological semimetallic perovskite SrIrO3 can be lifted simply by applying epitaxial constraints. In particular, the Dirac gap opens without breaking the P b n m mirror symmetry. In virtue of a symmetry-breaking analysis, we demonstrate that the original symmetry protection is related to the n -glide operation, which can be selectively broken by different heteroepitaxial structures. This symmetry protection renders the nodal line a nonsymmorphic Dirac semimetallic state. The results highlight the vital role of crystal symmetry in spin-orbit-coupled correlated oxides and provide a foundation for experimental realization of topological insulators in iridate-based heterostructures.
Mathematical Design Optimization of Wide-Field X-ray Telescopes: Mirror Nodal Positions and Detector Tilts
NASA Technical Reports Server (NTRS)
Elsner, R. F.; O'Dell, S. L.; Ramsey, B. D.; Weisskopf, M. C.
We describe a mathematical formalism for determining the mirror shell nodal positions and detector tilts that optimize the spatial resolution averaged over a field-of-view for a nested x-ray telescope, assuming known mirror segment surface prescriptions and known detector focal surface. The results are expressed in terms of ensemble averages over variable combinations of the ray positions and wave vectors in the flat focal plane intersecting the optical axis at the nominal on-axis focus, which can be determined by Monte-Carlo ray traces of the individual mirror shells. This work is part of our continuing efforts to provide analytical tools to aid in the design process for wide-field survey x-ray astronomy missions.
The modified nodal analysis method applied to the modeling of the thermal circuit of an asynchronous machine
NASA Astrophysics Data System (ADS)
Nedelcu, O.; Salisteanu, C. I.; Popa, F.; Salisteanu, B.; Oprescu, C. V.; Dogaru, V.
The complexity of electrical circuits or of equivalent thermal circuits that were considered to be analyzed and solved requires taking into account the method that is used for their solving. Choosing the method of solving determines the amount of calculation necessary for applying one of the methods. The heating and ventilation systems of electrical machines that have to be modeled result in complex equivalent electrical circuits of large dimensions, which requires the use of the most efficient methods of solving them. The purpose of the thermal calculation of electrical machines is to establish the heating, the overruns of temperatures or over-temperatures in some parts of the machine compared to the temperature of the ambient, in a given operating mode of the machine. The paper presents the application of the modified nodal analysis method for the modeling of the thermal circuit of an asynchronous machine.
Mathematical Design Optimization of Wide-Field X-ray Telescopes: Mirror Nodal Positions and Detector Tilts
NASA Technical Reports Server (NTRS)
Elsner, Ronald; O'Dell, Stephen; Ramsey, Brian; Weisskopf, Martin
We describe a mathematical formalism for determining the mirror shell nodal positions and detector tilts that optimize the spatial resolution averaged over a field-of-view for a nested x-ray telescope, assuming known mirror segment surface prescriptions and known detector focal surface. The results are expressed in terms of ensemble averages over variable combinations of the ray positions and wavevectors in the flat focal plane intersecting the optical axis at the nominal on-axis focus, which can be determined by Monte-Carlo ray traces of the individual mirror shells. This work is part of our continuing efforts to provide analytical tools to aid in the design process for wide-field survey x-ray astronomy missions.
Sentinel Lymph Node Mapping with Pathologic Ultrastaging: A Valuable Tool for Assessing Nodal Metastasis in Low-Grade Endometrial Cancer with Superficial Myoinvasion
Kim, Christine H.; Khoury-Collado, Fady; Barber, Emma L.; Soslow, Robert A.; Makker, Vicky; Leitao, Mario M.; Sonoda, Yukio; Alektiar, Kaled M.; Barakat, Richard R.; Abu-Rustum, Nadeem R.
Objective To report the incidence of nodal metastases in patients presenting with presumed low-grade endometrioid adenocarcinomas using a sentinel lymph node (SLN) mapping protocol including pathologic ultrastaging. Methods All patients from 9/2005-12/2011 who underwent endometrial cancer staging surgery with attempted SLN mapping for preoperative grade 1 (G1) or grade 2 (G2) tumors with <50% invasion on final pathology, were included. All lymph nodes were examined with hematoxylin and eosin (H&E). Negative SLNs were further examined using an ultrastaging protocol to detect micrometastases and isolated tumor cells. Results Of 425 patients, lymph node metastasis was found in 25 patients (5.9%) on final pathology—13 cases on routine H&E, 12 cases after ultrastaging. Patients whose tumors had a DMI <50% were more likely to have positive SLNs on routine H&E (p<0.005) or after ultrastaging (p=0.01) compared to those without myoinvasion. Conclusions Applying a standardized SLN mapping algorithm with ultrastaging allows for the detection of nodal disease in a presumably low-risk group of patients who in some practices may not undergo any nodal evaluation. Ultrastaging of SLNs can likely be eliminated in endometrioid adenocarcinoma with no myoinvasion. The long-term clinical significance of ultrastage-detected nodal disease requires further investigation as recurrences were noted in some of these cases. PMID:24099838
Clinical AV nodal reentrant tachycardia in a patient with left sided accessory pathway and immediate occurrence of antidromic AV reentrant tachycardia after slow pathway ablation.
Surber, Ralf; Kühnert, Helmut; Heinke, Matthias; Malur, Frank-Michael; Sigusch, Holger H; Figulla, Hans R
The only inducible arrhythmia in a patient with exclusive antegrade conducting left anterolateral accessory pathway, consists of slow/fast atrioventricular nodal reentrant tachycardia. After radiofrequency catheter ablation of the slow pathway, true antidromic AV reentrant tachycardia was easily induced by atrial pacing. Following ablation of the accessory pathway no arrhythmia could be induced.