text:
Facet Joints Arthrosis in Normal and Stenotic Lumbar Spines.
ABSTRACT: Study Design. A descriptive CT study of lumbar facet joint (FJ) arthrosis in general and spinal stenosis populations.Objective. To reveal the prevalence of FJ arthrosis in general and stenosis populations and to establish its relationship to age and gender.Summary of Background Data. FJ arthrosis is a common radiographic finding and has been suggested as a cause of low back and lower extremity pain. It is also considered a dominant player in the genesis of lumbar spinal stenosis. Although it is well accepted that FJ arthrosis is an age dependent phenomenon, controversies still exist as to its association with gender and its prevalence at different spine levels. Additionally, data on FJ arthrosis frequency in spinal stenosis population are missing.Methods. Two groups were studied. The first included 65 individuals with LSS (mean age 66 Ý 10 years) and the second, 150 individuals (mean age 52 Ý 19 years) without LSS related symptoms. Both left and right FJ arthrosis for each vertebral level (L3 to S1) were evaluated on CT images (Brilliance 64, Philips Medical System, Cleveland Ohio). Chi-Square, Linear-by-Linear Association and McNemar test were carried out to reveal the correlation between FJ arthrosis and demographic factors (age, gender) and prevalence at different lumbar levels in both stenosis and non-stenosis groups. Additionally, a 2-way ANOVA was used to determine the association between BMI and FJ arthrosis.Results. The rate of FJ arthrosis at L3-4 and L4-5 were significantly higher (P<0.001) in the stenotic group compared to the control. In the control group the prevalence of FJ arthrosis increases cephalo-caudally (L3-L4 = 16%, L4-L5 = 28%, L5-S1 = 55%), whereas in the stenotic group there is a sharp increase from L3-4 (27%) to L4-5 (58%), but not from L4-5 to L5-S1 (55%). No association between FJ arthrosis and gender was noted. Although, mean BMI was significantly smaller in the control group compared to the stenotic group, no association between BMI and facet arthrosis was found. In the general population the prevalence of FJ arthrosis at all three levels was greater for the right side; however, significant difference (P = 0.004) was obtained only for L3-4. In all joints studied, the prevalence of FJ arthrosis increases considerably from the young age cohort (18-39) to the old age cohort (>60). Nevertheless, 10% of the young individuals (18-39) have already manifested FJ arthrosis at L5-S1. No arthrosis at that age was observed at L3-4.Conclusion. FJ arthrosis is an age-dependent and BMI and gender-independent phenomenon. In the general population, the prevalence of FJ arthrosis increases cephalo-caudally with the highest frequency at L5-S1. In the stenotic group, the highest frequency was observed at the two caudal levels; L4-5 and L5-S1. The prevalence of FJ arthrosis was greater for the right side. PMID:21270678
J, Abbas; K, Hamoud; S, Peleg; H, May; Y, Masharawi; H, Cohen; N, Peled; I, Hershkovitz
Comparison of computed tomography and magnetic resonance imaging in the evaluation of facet tropism and facet arthrosis in degenerative cervical spondylolisthesis.
The aim of this study was to determine the reliability of magnetic resonance imaging (MRI) in the assessment of facet tropism and facet arthrosis of spondylolisthesis levels in degenerative cervical spondylolisthesis as compared to computed tomography (CT). The discrepancies in the interpretation of CT and MRI data in the evaluation of facet tropism and arthrosis have given rise to questions regarding the reliability of comparisons of the two techniques. Using a 4-point scale, 3 blinded readers independently graded the severity of facet tropism and facet arthrosis of 79 cervical facet joints on axial T2-weighted and sagittal T1 and T2-weighted turbo spin echo images as well as the corresponding axial CT scans. All results were subjected to the kappa coefficient statistic for strength of agreement. In the assessment of the severity of facet arthrosis, intermethod agreement (weighted ?) between CT scanning with a moderate inter-rater reliability (range ? = 0.43-0.57) and MRI with fair inter-rater reliability (range ? = 0.23-0.38) was 0.76 and 0.43 for the severity of facet tropism and facet arthrosis, respectively. Intra-rater reliability for the severity of facet arthrosis was moderate to substantial for CT and was moderate for MRI scans. Intra-rater reliability for the severity of facet tropism was substantial to very good for CT and substantial for MRI scans. MRI can reliably determine the presence or degree of facet tropism but not facet arthrosis. Therefore, for a comprehensive assessment of cervical facet joint degeneration, both a CT and an MRI scan should be performed. PMID:24938702
Xu, C; Ding, Z H; Xu, Y K
Image-guided facet joint injection
Chronic spine pain poses a peculiar diagnostic and therapeutic challenge due to multiple pain sources, overlapping clinical features and nonspecific radiological findings. Facet joint injection is an interventional pain management tool for facet-related spinal pain that can be effectively administered by a radiologist. This technique is the gold standard for identifying facet joints as the source of spinal pain. The major indications for facet injections include strong clinical suspicion of the facet syndrome, focal tenderness over the facet joints, low back pain with normal radiological findings, post-laminectomy syndrome with no evidence of arachnoiditis or recurrent disc disease, and persistent low back pain after spinal fusion. The contraindications are more ancillary, with none being absolute. Like any synovial joint degeneration, inflammation and injury can lead to pain on motion, initiating a vicious cycle of physical deconditioning, irritation of facet innervations and muscle spasm. Image-guided injection of local anesthetic and steroid into or around the facet joint aims to break this vicious cycle and thereby provide pain relief. This outpatient procedure has high diagnostic accuracy, safety and reproducibility but the therapeutic outcome is variable.
Peh, WCG
Osteoarthritis of the spine: the facet joints
Osteoarthritis (OA) of the spine involves the facet joints, which are located in the posterior aspect of the vertebral column and, in humans, are the only true synovial joints between adjacent spinal levels. Facet joint osteoarthritis (FJ OA) is widely prevalent in older adults, and is thought to be a common cause of back and neck pain. The prevalence of facet-mediated pain in clinical populations increases with increasing age, suggesting that FJ OA might have a particularly important role in older adults with spinal pain. Nevertheless, to date FJ OA has received far less study than other important OA phenotypes such as knee OA, and other features of spine pathoanatomy such as degenerative disc disease. This Review presents the current state of knowledge of FJ OA, including relevant anatomy, biomechanics, epidemiology, and clinical manifestations. We present the view that the modern concept of FJ OA is consonant with the concept of OA as a failure of the whole joint, and not simply of facet joint cartilage.
Gellhorn, Alfred C.; Katz, Jeffrey N.; Suri, Pradeep
Bone mineral density in patients with destructive arthrosis of the hip joint.
Recent reports have shown the existence of subchondral insufficiency fracture in rapidly destructive arthrosis of the hip joint (RDA), and the findings suggest that osteopenia is related to the pathogenesis of the rapid progression of this disease. Therefore, we measured bone mineral density (BMD) in RDA patients. We measured BMD of the lumbar spine, radius, and calcaneus using dual-energy X-ray absorptiometry in 19 patients with RDA and 75 with osteoarthritis of the hip (OA) and compared BMD at different skeletal sites between RDA and OA patients. No significant differences were observed in BMD of the lumbar spine, ultradistal radius, mid-radius, and calcaneous between the RDA and OA groups. Our data suggest that RDA is not accompanied by generalized osteoporosis. Factors other than generalized bone status, for example, BMD around the affected hip joint before destruction, need to be analyzed to elucidate the pathophysiological mechanism of RDA. PMID:23921834
Okano, Kunihiko; Aoyagi, Kiyoshi; Enomoto, Hiroshi; Osaki, Makoto; Chiba, Ko; Yamaguchi, Kazumasa
Surgical Tips to Preserve the Facet Joint during Microdiscectomy.
Lumbar microdiscectomy (MD) is the gold standard for treatment of lumbar disc herniation. Generally, the surgeon attempts to protect the facet joint in hopes of avoiding postoperative pain/instability and secondary degenerative arthropathy. We believe that preserving the facet joint is especially important in young patients, owing to their life expectancy and activity. However, preserving the facet joint is not easy during lumbar MD. We propose several technical tips (superolateral extension of conventional laminotomy, oblique drilling for laminotomy, and additional foraminotomy) for facet joint preservation during lumbar MD. PMID:24294466
Park, Man-Kyu; Kim, Kyoung-Tae; Cho, Dae-Chul; Sung, Joo-Kyung
Desmoid tumor of the facet joint: a case report.
Desmoid tumors represent a particular type of fibromatosis. The common sites for extra-abdominal desmoid tumors, known as aggressive fibromatosis, are the shoulder, chest wall, and thigh. Desmiod tumors are rare at facet joints of the spine. We describe a patient with a desmoid tumor of a lumbar facet joint. PMID:24757464
Nam, Han Ga Wi; Moon, Seung-Myung; Jeon, Sei-Woong; Hwang, Hyung Sik
Low back pain and the zygapophysial (facet) joints
Dreyer SJ, Dreyfuss PH. Low back pain and the zygapophysial (facet) joints was performed based on a literature search of scientific journals and textbooks. Recent studies estimate that 15% to 40% of chronic low back pain is due to the zygapophysial joints. The histological basis for zygapophysial joint pain has been scientifically established, but the precise clinical etiology remains undetermined.
Susan J. Dreyer; Paul H. Dreyfuss
Biomechanical characterisation of ovine spinal facet joint cartilage.
The spinal facet joints are known to be an important component in the kinematics and the load transmission of the spine. The articular cartilage in the facet joint is prone to degenerative changes which lead to back pain and treatments for the condition have had limited long term success. There is currently a lack of information on the basic biomechanical properties of the facet joint cartilage which is needed to develop tissue substitution or regenerative interventions. In the present study, the thickness and biphasic properties of ovine facet cartilage were determined using a combination of indentation tests and computational modelling. The equilibrium biphasic Young's modulus and permeability were derived to be 0.76Ý0.35 MPa and 1.61Ý1.10æ10?¿? m?/(Ns) respectively, which were within the range of cartilage properties characterised from the human synovial joints. The average thickness of the ovine facet cartilage was 0.52Ý0.10 mm, which was measured using a needle indentation test. These properties could potentially be used for the development of substitution or tissue engineering interventions and for computational modelling of the facet joint. Furthermore, the developed method to characterise the facet cartilage could be used for other animals or human donors. PMID:22483055
Abd Latif, Mohd Juzaila; Jin, Zhongmin; Wilcox, Ruth K
Uncovertebral joint injury in cervical facet dislocation: the headphones sign
The purpose of our study is to demonstrate the uncovertebral mal-alignment as a reliable indirect sign of cervical facet joint\\u000a dislocation. We examined the uncovertebral axial plane alignment of 12 patients with unilateral and bilateral cervical facet\\u000a joint dislocation (UCFJD and BCFJD, respectively), comparing its frequency to the reverse hamburger bun sign on CT and MR\\u000a axial images. Of the
Francesco Palmieri; Victor N. Cassar-Pullicino; Claudia DellAtti; Radhesh K. Lalam; Bernhard J. Tins; Prudencia N. M. Tyrrell; Iain W. McCall
[Partial autologous reconstruction of the thumb carpometacarpal joint for posttraumatic arthrosis].
We report about a successful reconstruction of the first carpometacarpal joint (CMC-joint) of the right hand in a 23 years old man with a posttraumatic defect using the OATS-technique (Osteochondral Autologous Transfer System). 2 autologous osteochondral cylinders with matching surfaces were harvested from the knee joint and implanted in osteoarthritic areas of the CMC-1 joint surface in press fit technique. After primary healing clinical and radiological controls were assessed 6 and 12 weeks postoperatively. At clinical follow-up 1 year after the function of the CMC-1 joint was completely free, function nearly fully restored. The osteochondral grafts revealed a sound healing in an additional MRI-investigation. 3 years after the operation, the DASH-score of the patient was measured with 4.2 points. With view to the encouraging results of the OATS technique in other joints it should be taken into consideration in cases of osteoarthritic CMC-1 joint respecting indicatory limitations. PMID:23519714
Kollig, E; Hentsch, S; Johann, M; Franke, A
Arthritis of the subtalar joint associated with sustentaculum tali facet configuration.
The articular facets of the sustentaculum tali have a variety of configurations that are generally viewed as nonmetric traits of little functional significance. Bruckner (1987), in contrast, has hypothesised that sustentaculum tali facet variations are functionally important because they influence subtalar joint stability. To test this hypothesis, 191 calcanei were analysed for correlations between sustentaculum tali facet morphology and osteoarthritis of the subtalar joint. Calcanei with 2 separate sustentaculum tali facets had a lower frequency of arthritic changes associated with joint instability than calcanei with other facet configurations. This finding supports Bruckner's hypothesis that subtalar joint facet configuration is a factor in foot mobility.
Drayer-Verhagen, F
Cervical Facet Joint Injections in the Neck and Shoulder Pain
The effects from cervical facet joint injections in those patients who have been complaining cervical zygapophyseal joint pain were compared. The patients were diagnosed originally as myofascial pain syndrome (MPS), cervical herniated nucleus pulposus (HNP), and whiplash-associated disorders (WAD). Patients with the zygapophyseal joints pain of C5-6 and C6-7 were classified by their pain origin as MPS, HNP, and WAD. All patients had been undergone cervical zygapophyseal joints injections with the mixture of lidocaine and triamcinolone unilaterally or bilaterally through the posterior approach under C-arm imaging guide. The therapeutic effects were compared with reduction of numeric rating scale (NRS) of pain before and immediately after blockade and symptom-free periods in each group after 12 months. Symptom durations before injections were 16.1Ý9.6, 4.6Ý1.9 and 4.1Ý1.1 months in each MPS, HNP, and WAD groups. The reductions of NRS immediately after the blockade among the three groups were not different. However, the symptom-free duration after blockade lasted longer in the HNP group than the other two groups. In patients with cervical zygapophyseal pain syndromes, the analgesic effect from cervical facet joint blocks lasted longer in cervical HNP than MPS or WAD.
Choi, Sung-Hwan; Kim, Tae-Kyun; Shin, Sang-Wook; Kim, Cheul-Hong; Kim, Jeung-Il
Facet joint laser radiation: tissue effects of a new clinical laser application
NASA Astrophysics Data System (ADS)
Chronic unilateral and bilateral back pain with pseudoradicular symptoms, is a common clinical syndrome, which in many cases can be related to the facet joint syndrome. The pain is caused by mechanical affection of synovial and capsular nerve terminals. Therefore, current therapeutical attempts including physical therapy, intra-articular injection of local anesthetics and steroids and thermocoagulation of the facet joint with a thermocoagulator, are performed. We confirmed laser coagulation of the facet joint. Porcine cadaveric spines were treated immediately after death by intra-articular facet joint laser radiation. With the pulsed Nd:YAG laser (1064 nm) altogether 600 J were applied in three different places 4 mm apart at the top of the facet joint. The results showed that facet joint laser radiation leads to a small (about 1 - 2 mm diameter) lesion restricted to the facet joint cavity and its synovia. Histologically, we found a central carbonization zone and necrosis, including almost the whole cartilage and approximately 0.2 mm of the adjacent bone. These changes are similar to Nd:Yag-laser applications in other skeletal regions. It is suggested that these changes may lead to facet joint denervation by coagulation of the synovial nerve terminals. Cicatration of the laser lesion might cause ankylosis of this joint. In sum, facet joint laser radiation could be an alternative therapeutical tool for lower back pain of the facet joint syndrome type. Therefore, future clinical application of this technique seems to be very promising.
Werkmann, Klaus; Thal, Dietmar R.
Prevalence of facet joint pain in chronic spinal pain of cervical, thoracic, and lumbar regions
BACKGROUND: Facet joints are a clinically important source of chronic cervical, thoracic, and lumbar spine pain. The purpose of this study was to systematically evaluate the prevalence of facet joint pain by spinal region in patients with chronic spine pain referred to an interventional pain management practice. METHODS: Five hundred consecutive patients with chronic, non-specific spine pain were evaluated. The
Laxmaiah Manchikanti; Mark V Boswell; Vijay Singh; Vidyasagar Pampati; Kim S Damron; Carla D Beyer
Review of existing grading systems for cervical or lumbar disc and facet joint degeneration
The aim of this literature review was to present and to evaluate all grading systems for cervical and lumbar disc and facet joint degeneration, which are accessible from the MEDLINE database. A MEDLINE search was conducted to select all articles presenting own grading systems for cervical or lumbar disc or facet joint degeneration. To give an overview, these grading systems
Annette Kettler; Hans-Joachim Wilke
Magnetic resonance-guided focused ultrasound treatment of facet joint pain: summary of preclinical phase
Study design A phantom experiment, two thermocouple experiments, three in vivo pig experiments, and a simulated treatment on a healthy human volunteer were conducted to test the feasibility, safety, and efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) for treating facet joint pain. Objective The goal of the current study was to develop a novel method for accurate and safe noninvasive facet joint ablation using MRgFUS. Summary of background data Facet joints are a common source of chronic back pain. Direct facet joint interventions include medial branch nerve ablation and intra-articular injections, which are widely used, but limited in the short and long term. MRgFUS is a breakthrough technology that enables accurate delivery of high-intensity focused ultrasound energy to create a localized temperature rise for tissue ablation, using MR guidance for treatment planning and real-time feedback. Methods We validated the feasibility, safety, and efficacy of MRgFUS for facet joint ablation using the ExAblate 2000Û System (InSightec Ltd., Tirat Carmel, Israel) and confirmed the system's ability to ablate the edge of the facet joint and all terminal nerves innervating the joint. A phantom experiment, two thermocouple experiments, three in vivo pig experiments, and a simulated treatment on a healthy human volunteer were conducted. Results The experiments showed that targeting the facet joint with energies of 150450 J provides controlled and accurate heating at the facet joint edge without penetration to the vertebral body, spinal canal, or root foramina. Treating with reduced diameter of the acoustic beam is recommended since a narrower beam improves access to the targeted areas. Conclusions MRgFUS can safely and effectively target and ablate the facet joint. These results are highly significant, given that this is the first study to demonstrate the potential of MRgFUS to treat facet joint pain.
[Synovial cyst in the lumbar facet joint. A rare cause of lumbar-sciatic pain].
Synovial cysts of the facet joints are uncommon lesions which may be asymptomatic or present as low back pain, with or without radicular symptoms. They are considered to be secondary to trauma or degenerative joint disease, and they occur more frequently in patients with spondylolisthesis. Diagnosis is normally achieved with computed tomography or magnetic resonance, which show a cystic lesion located laterally adjacent to the facet joint. We review the literature and report a patient who presented with first sacral nerve root symptoms attributable to a ganglion cyst of the left L5 S1 facet joint. Treatment was curative and consisted in excision of the cyst. PMID:9333919
Villas, C; Leyes, M
Lumbar Facet Joint Arthritis Is Associated with More Coronal Orientation of the Facet Joints at the Upper Lumbar Spine
We retrospectively analyzed CT scans of 620 individuals, who presented to our traumatology department between 2008 and 2010. Facet joint (FJ) arthritis was present in 308 (49.7%) individuals with a mean grade of 1. It was seen in 27% of individuals ?40 years and in 75% of individuals ?41 years (P < 0.0001) as well as in 52% of females and 49% of males (P = 0.61). Mean FJ orientation was 30.4¯ at L2/3, 38.7¯ at L3/4, 47¯ at L4/5, and 47.3¯ at L5/S1. FJ arthritis was significantly associated with more coronal (increased degree) FJ orientation at L2/3 (P = 0.03) with a cutoff point at ?32¯. FJs were more coronally oriented (48.8¯) in individuals ?40 years and more sagittally oriented (45.6¯) in individuals ?41 years at L5/S1 (P = 0.01). Mean FJ asymmetry was 4.89¯ at L2/3, 6.01¯ at L3/4, 6.67¯ at L4/5, and 7.27¯ at L5/S1, without a significant difference for FJ arthritis. FJ arthritis is common, increases with age, and affects both genders equally. More coronally oriented FJs (?32¯) in the upper lumbar spine may be an individual risk factor for development of FJ arthritis.
Jentzsch, Thorsten; Geiger, James; Zimmermann, Stefan M.; Slankamenac, Ksenija; Nguyen-Kim, Thi Dan Linh; Werner, Clement M. L.
Material Properties of the Human Lumbar Facet Joint Capsule
The human facet joint capsule is one of the structures in the lumbar spine that constrains motions of vertebrae during global spine loading (e.g., physiological flexion). Computational models of the spine have not been able to include accurate nonlinear and viscoelastic material properties, as they have not previously been measured. Capsules were tested using a uniaxial ramp-hold protocol or a haversine displacement protocol using a commercially available materials testing device. Plane strain was measured optically. Capsules were tested both parallel and perpendicular to the dominant orientation of the collagen fibers in the capsules. Viscoelastic material properties were determined. Parallel to the dominant orientation of the collagen fibers, the complex modulus of elasticity was E* = 1.63MPa, with a storage modulus of E? = 1.25MPa and a loss modulus of: E? = 0.39MPa. The mean stress relaxation rates for static and dynamic loading were best fit with first-order polynomials: B (?) = 0.1110 ? ? 0.0733 and B (?) = ?0.1249? 11794-8181 +0.0190, respectively. Perpendicular to the collagen fiber orientation, the viscous and elastic secant moduli were 1.81 and 1.00 MPa, respectively. The mean stress relaxation rate for static loading was best fit with a first-order polynomial: B (?) = ? 0.04? ? 0.06. Capsule strength parallel and perpendicular to collagen fiber orientation was 1.90 and 0.95 MPa, respectively, and extensibility was 0.65 and 0.60, respectively. Poissons ratio parallel and perpendicular to fiber orientation was 0.299 and 0.488, respectively. The elasticity moduli were nonlinear and anisotropic, and capsule strength was larger aligned parallel to the collagen fibers. The phase lag between stress and strain increased with haversine frequency, but the storage modulus remained large relative to the complex modulus. The stress relaxation rate was strain dependent parallel to the collagen fibers, but was strain independent perpendicularly.
Little, Jesse S.; Khalsa, Partap S.
The relationship between lower neck shear force and facet joint kinematics during automotive rear impacts.
A primary goal of biomechanical safety research is the definition of localized injury thresholds in terms of quantities that are repeatable and easily measureable during experimentation. Recent biomechanical experimentation using human cadavers has highlighted the role of lower cervical facet joints in the injury mechanism resulting from low-speed automotive rear impacts. The present study was conducted to correlate lower neck forces and moments with facet joint motions during simulated rear impacts in an effort to define facet joint injury tolerance thresholds that can be used to assess automobile safety. Four male and four female intact head-neck complexes were obtained from cadaveric specimens and subjected to simulated automotive rear impacts using a pendulum-minisled device. Cervical spine segmental angulations and localized facet joint kinematics were correlated to shear and axial forces, and bending moments at the cervico-thoracic junction using linear regression. R(2) coefficients indicated that spinal kinematics correlated well with lower neck shear force and bending moment. Correlation slope was steeper in female specimens, indicating greater facet joint motions for a given loading magnitude. This study demonstrated that lower neck loads can be used to predict lower cervical facet joint kinematics during automotive rear impacts. Higher correlation slope in female specimens corresponds to higher injury susceptibility in that population. Although lower neck shear force and bending moment demonstrated adequate correlation with lower cervical facet joint motions, shear force is likely the better predictor due to similarity in the timing of peak magnitudes with regard to maximum facet joint motions. PMID:21433081
Stemper, Brian D; Yoganandan, Narayan; Pintar, Frank A; Maiman, Dennis J
Facet Joint Pain in Chronic Spinal Pain: An Evaluation of Prevalence and False-positive Rate of Diagnostic Blocks
Study Design: A retrospective review. Objectives: Evaluation of the prevalence of facet or zygapophy- sial joint pain in chronic spinal pain of cervical, thoracic, and lumbar origin by using controlled, comparative local anesthetic blocks and evaluation of false-positive rates of single blocks in the diagnosis of chronic spinal pain of facet joint origin. Summary of Background Data: Facet or zygapophysial
Rajeev Manchukonda; Kavita N. Manchikanti; Kimberly A. Cash; Vidyasagar Pampati; Laxmaiah Manchikanti
Increase in facet joint loading after nucleotomy in the human lumbar spine.
Low-back pain has been related to degenerative changes after nucleotomy. Although several etiologies for pain after nucleotomy have been proposed, there is evidence of pain arising in the facet joints in general, which may be related to changes in load transfer. This study addresses the effect of nucleotomy on facet joint loading. Nine human lumbar motion segments (age: 40-59 years) were loaded in axial compression and extension-flexion. Reaction forces were compared with soft tissue structures sequentially removed. After nucleotomy the facets supported significantly greater load, almost doubling from a median of 8.6% of the applied external force to 15.8%. Force transmission related to the capsular ligament increased significantly from an intact median of 1.2-5.1% after nucleotomy. No correlation was observed between force increase on the facets and the proportion of disc nucleus removed. Even a small quantity of nucleus removal (range: 0.7-1.7g) increased the forces transmitted over the facet joints, both with and without capsular ligaments. This suggests that the proportion of material removed might not be important clinically with regard to facet joint degeneration and pain. PMID:24661835
Ivicsics, M F; Bishop, N E; P■schel, K; Morlock, M M; Huber, G
Prevalence of facet joint pain in chronic spinal pain of cervical, thoracic, and lumbar regions
Background Facet joints are a clinically important source of chronic cervical, thoracic, and lumbar spine pain. The purpose of this study was to systematically evaluate the prevalence of facet joint pain by spinal region in patients with chronic spine pain referred to an interventional pain management practice. Methods Five hundred consecutive patients with chronic, non-specific spine pain were evaluated. The prevalence of facet joint pain was determined using controlled comparative local anesthetic blocks (1% lidocaine or 1% lidocaine followed by 0.25% bupivacaine), in accordance with the criteria established by the International Association for the Study of Pain (IASP). The study was performed in the United States in a non-university based ambulatory interventional pain management setting. Results The prevalence of facet joint pain in patients with chronic cervical spine pain was 55% 5(95% CI, 49% 61%), with thoracic spine pain was 42% (95% CI, 30% 53%), and in with lumbar spine pain was 31% (95% CI, 27% 36%). The false-positive rate with single blocks with lidocaine was 63% (95% CI, 54% 72%) in the cervical spine, 55% (95% CI, 39% 78%) in the thoracic spine, and 27% (95% CI, 22% 32%) in the lumbar spine. Conclusion This study demonstrated that in an interventional pain management setting, facet joints are clinically important spinal pain generators in a significant proportion of patients with chronic spinal pain. Because these patients typically have failed conservative management, including physical therapy, chiropractic treatment and analgesics, they may benefit from specific interventions designed to manage facet joint pain.
Manchikanti, Laxmaiah; Boswell, Mark V; Singh, Vijay; Pampati, Vidyasagar; Damron, Kim S; Beyer, Carla D
Ultrasound-guided facet joint injection to treat a spinal cyst.
Lumbar spinal cysts often present with backache and may be accompanied by lower extremity weakness as well as radiation pain if root compression occurs. The treatment regimens include anti-inflammatory drugs, physical therapy, procedures guided by fluoroscopy or computed tomography, and surgery. We report the case of a patient with a symptomatic lumbar spinal cyst at the L4-L5 facet joint. The symptoms immediately remitted after ultrasound-guided steroid-lidocaine injection into the L4-L5 facet joint. Magnetic resonance imaging follow up 4 months after injection showed complete resolution of the cyst. PMID:24631041
Lin, Tung-Liang; Chung, Chin-Teng; Lan, Howard Haw-Chang; Sheen, Huey-Min
Pyogenic arthritis of the facet joint with concurrent epidural and paraspinal abscess: a case report.
Pyogenic arthritis of lumber spinal facet joints is an extremely rare condition. There are only 40 reported cases worldwide. Most cases were associated with history of paravertebral injection, which was not found in our patient. At the time of hospital admission, he had no abnormal magnetic resonance image findings. Two weeks later, he developed pyogenic facet joint arthritis associated with paravertebral and epidural abscess. This report is the first to describe delayed presentation of pyogenic arthritis associated with paravertebral abscess and epidural infection. PMID:22164319
Rhyu, Kee-Won; Park, Sang-Eun; Ji, Jong-Hun; Park, In; Kim, Young-Yul
Clinical results of resection arthrodesis by triangular external fixation for posttraumatic arthrosis of the ankle joint in 89 cases
The methods for ankle arthrodesis differ significantly, probably a sign that no method is clearly superior to others. In the last ten years there is a clear favour toward internal fixation. We retrospectively evaluate the technique and evaluate the clinical long term results of external fixation in a triangular frame. Patients and Methods From 1994 to 2001 a consecutive series of 95 patients with end stage arthritis of the ankle joint were treated. Retrospectively the case notes were evaluated regarding trauma history, medical complaints, further injuries and illnesses, walking and pain status and occupational issues and the clinical examination before arthrodesis. Mean age at the index procedure was 45.4 years (18-82), 67 patients were male (70.5%). Via a bilateral approach the malleoli and the joint surfaces were resected. An AO fixator was applied with two Steinmann-nails inserted with approximately 8 cm distance in the distal tibia, one in the neck of the talus and one in the dorsal calcaneus. The fixator was removed after approximately 12 weeks. Follow up examination at mean 4.4 years included a standardised questionnaire and a clinical examination including the criteria of the AOFAS-Score and radiographs. Results: Due to different complications, 8 (8.9%) further surgical procedures were necessary including 1 below knee amputation. In 4 patients a non-union of the ankle arthrodesis developed (4.5%). The mean AOFAS score improved from 20.8 to 69.3 points. Conclusion Non-union rates and clinical results of arthrodesis by triangular external fixation of the ankle joint do not differ to internal fixation methods. The complication rate and the reduced patient comfort reserve this method mainly for infected arthritis and complicated soft tissue situations.
Human facet cartilage: swelling and some physico-chemical characteristics as a function of age. Part 1: Swelling of human facet joint cartilage.
The hydration of cartilage from human facet joints was measured after the joints had been subjected to different treatments. One group of facets was opened and directly exposed to physiologic saline solution before extraction of cartilage plugs. The plugs were weighed, re-equilibrated in fluid, and weighed again. The swelling results obtained under these conditions were compared with those when similar plugs of cartilage were excised from joints that had not been exposed to solution or had been exposed to solution while still closed. It was found that swelling was least (and similar in value to hip cartilage) for joints that had been exposed open to saline solution, highest for joints that had not been exposed to solution, and intermediate for joints that had been exposed to solution while still closed. The same trends were observed whether the cartilage on the joint was intact or fibrillated, although in each group the swelling and the final hydration were higher for fibrillated than for intact tissue. It was concluded that facet cartilage, unlike human hip or knee cartilage, is underhydrated when excised from the joint. This underhydration is thought to reflect the permanent presence of stresses in vivo on some part of the facet joints, the position of the loaded site changing with time. The authors attempted to distinguish between the swelling caused by this underhydration and that from disruption of the collagen network in the case of fibrillated specimens. PMID:1626303
Tobias, D; Ziv, I; Maroudas, A
Qualitative and quantitative assessment of degeneration of cervical intervertebral discs and facet joints.
Degeneration of intervertebral discs and facet joints is one of the most frequently encountered spinal disorders. In order to describe and quantify degeneration and evaluate a possible relationship between degeneration and biomechanical parameters, e.g., the intervertebral range of motion and intradiscal pressure, a scoring system for degeneration is mandatory. However, few scoring systems for the assessment of degeneration of the cervical spine exist. Therefore, two separate objective scoring systems to qualitatively and quantitatively assess the degree of cervical intervertebral disc and facet joint degeneration were developed and validated. The scoring system for cervical disc degeneration consists of three variables which are individually scored on neutral lateral radiographs: "height loss" (0-4 points), "anterior osteophytes" (0-3 points) and "endplate sclerosis" (0-2 points). The scoring system for facet joint degeneration consists of four variables which are individually scored on neutral computed tomography scans: "hypertrophy" (0-2 points), "osteophytes" (0-1 point), "irregularity" on the articular surface (0-1 point) and "joint space narrowing" (0-1 point). Each variable contributes with varying importance to the overall degeneration score (max 9 points for the scoring system of cervical disc degeneration and max 5 points for facet joint degeneration). Degeneration of 20 discs and facet joints of 20 patients was blindly assessed by four raters: two neurosurgeons (one senior and one junior) and two radiologists (one senior and one junior), firstly based on first subjective impression and secondly using the scoring systems. Measurement errors and inter- and intra-rater agreement were determined. The measurement error of the scoring system for cervical disc degeneration was 11.1 versus 17.9% of the subjective impression results. This scoring system showed excellent intra-rater agreement (ICC = 0.86, 0.75-0.93) and excellent inter-rater agreement (ICC = 0.78, 0.64-0.88). Surgeons as well as radiologists and seniors as well as juniors obtained excellent inter- and intra-rater agreement. The measurement error of the scoring system for cervical facet joint degeneration was 20.1 versus 24.2% of the subjective impression results. This scoring system showed good intra-rater agreement (ICC = 0.71, 0.42-0.89) and fair inter-rater agreement (ICC = 0.49, 0.26-0.74). Both scoring systems fulfilled the criteria for recommendation proposed by Kettler and Wilke. Our scoring systems can be reliable and objective tools for assessing cervical disc and facet joint degeneration. Moreover, the scoring system of cervical disc degeneration was shown to be experience- and discipline-independent. PMID:19005690
Walraevens, Joris; Liu, Baoge; Meersschaert, Joke; Demaerel, Philippe; Delye, Hans; Depreitere, Bart; Vander Sloten, Jos; Goffin, Jan
Development of an in vivo method to investigate biomechanical and neurophysiological properties of spine facet joint capsules
Facet joint capsules (FJC) may experience large mechanical deformation under spine motion. There has been no previous quantitative study of the relationship between capsular strain and sensory nerve activation in spine FJC in vivo. Space limitation in the cervical spine makes such a study difficult, as the facet joint must be loaded while simultaneously monitoring nerve discharge from nerve roots
Ying Lu; Chaoyang Chen; Srinivasu Kallakuri; Ajit Patwardhan; John M. Cavanaugh
Neuronal hyperexcitability in the dorsal horn after painful facet joint injury
Excessive cervical facet capsular ligament stretch has been implicated as a cause of whiplash-associated disorders following rear-end impacts, but the pathophysiological mechanisms that produce chronic pain in these cases remain unclear. Using a rat model of C6/C7 cervical facet joint capsule stretch that produces sustained mechanical hyperalgesia, the presence of neuronal hyperexcitability was characterized 7 days after joint loading. Extracellular recordings of spinal dorsal horn neuronal activity between C6 and C8 (117 neurons) were obtained from anesthetized rats, with both painful and non-painful behavioral outcomes established by the magnitude of capsule stretch. The frequency of neuronal firing during noxious pinch (p<0.0182) and von Frey filaments applications (426 g) to the forepaw was increased (p<0.0156) in the painful group compared to the non-painful and sham groups. In addition, the incidence and frequency of spontaneous and afterdischarge firing were greater in the painful group (p<0.0307) relative to sham. The proportion of cells in the deep laminae that responded as wide dynamic range neurons also was increased in the painful group relative to non-painful or sham groups (p<0.0348). These findings suggest that excessive facet capsule stretch, while not producing visible tearing, can produce functional plasticity of dorsal horn neuronal activity. The increase in neuronal firing across a range of stimulus magnitudes observed at day 7 post-injury provides the first direct evidence of neuronal modulation in the spinal cord following facet joint loading, and suggests that facet-mediated chronic pain following whiplash injury is driven, at least in part, by central sensitization.
Quinn, Kyle P.; Dong, Ling; Golder, Francis J.; Winkelstein, Beth A.
Facet joint pain and the role of neural blockade in its management
Chronic spinal pain is a common medical problem with serious financial and social consequences. Among the various structures\\u000a with potential for producing pain in the spine, facet joints as sources of chronic spinal pain have attracted considerable\\u000a attention and controversy. Significant progress has been made in precision diagnosis of spinal pain with neural blockade,\\u000a in the face of less than
Laxmaiah Manchikanti
[Modification of sagittal osteotomy of the patella as treatment of excentric chondromalacia or retropatellar arthrosis. Preliminary communication (author's transl)].
The author presents a modification of Morscher's sagittal osteotomy of the patella especially for the treatment of excentric chondromalacia. Congruity of the joint spaces in this modification is achieved through removal of an anteriorly based bone wedge from the patella after sagittal wedge osteotomy allowing the lifting of one or the other patellar facet. This osteotomy is indicated in all cases of unilateral chondromalacia or arthrosis with narrowing of the two joint spaces viewed on tangential patello-femoral X-rays. Following the ideas of Pauwels and Maquet, restoration of a wide joint space and reduction of local excessive stress result in reparative mechanisms of the cartilage involved. The to date preliminary clinical results in 5 cases (1 year max. follow-up) are encouraging. PMID:7467728
Griss, P
Prediction of the human thoracic and lumbar articular facet joint morphometry from radiographic images
The articular facet joints (AFJ) play an important role in the biomechanics of the spine. Although it is well known that some AFJ dimensions (e.g. facet height/width or facet angles) play a major role in spinal deformities such as scoliosis, little is known about statistical correlations between these dimensions and the size of the vertebral bodies. Such relations could allow patient-specific prediction of AFJ morphometry from a few dimensions measurable by X-ray. This would be of clinical interest and could also provide parameters for mathematical modeling of the spine. Our purpose in this study was to generate prediction equations for 20 parameters of the human thoracic and lumbar AFJ from T1 to L4 as a function of only one given parameter, the vertebral body height posterior (VBHP). Linear and nonlinear regression analyses were performed with published anatomical data, including linear and angular dimensions of the AFJ and vertebral body heights, to find the best functions to describe the correlations between these parameters. Third-order polynomial regressions, in contrast to the linear, exponential and logarithmic regressions, provided moderate to high correlations between the AFJ parameters and vertebral body heights; e.g. facet height superior and interfacet width (R2, 0.6050.880); facet height inferior, interfacet height and sagittal/transverse angle superior (R2, 0.8750.973). Different correlations were found for facet width and transverse angle inferior in the thoracic (R2, 0.7030.930) and lumbar (R2, 0.4570.892) regions. A set of 20 prediction equations for AFJ parameters was generated (P-values < 0.005, anova). Comparison of the AFJ predictions with experimental data indicated mean percent errors < 13%, with the exception of the thoracolumbar junction (T12L1). It was possible to establish useful predictions for human thoracic and lumbar AFJ dimensions based on the size of the vertebral bodies. The generated set of equations allows the prediction of 20 AFJ parameters per vertebral level from the measurement of the parameter VBHP, which is easily performed on lateral X-rays. As the vertebral body height is unique for each person and vertebral level, the predicted AFJ parameters are also specific to an individual. This approach could be used for parameterized patient-specific modeling of the spine to explore the clinically important mechanical roles of the articular facets in pathological conditions, such as scoliosis.
Kunkel, Maria E; Schmidt, Hendrik; Wilke, Hans-Joachim
Effectiveness of lumbar facet joint nerve blocks in chronic low back pain: a randomized clinical trial.
This randomized clinical trial was designed to determine the effectiveness of therapeutic lumbar facet joint nerve blocks. Two hundred patients were evaluated with controlled diagnostic blocks for the presence of facet joint mediated pain. Eighty four patients, or 42% were determined to have lumbar facet joint mediated pain. These patients were randomly allocated into two groups: Group I receiving therapeutic injections with local anesthetic and Sarapin, and Group II receiving therapeutic injections with a mixture of local anesthetic, Sarapin, and methyl prednisolone. A total of 73 patients were treated with medial branch blocks under fluoroscopy. Results showed that patients underwent multiple procedures over a period of 2(1/2) years. The mean number of procedures or interventions was 2.5 +/- 0.09 from 1 to 3 months, whereas it was 4 +/- 0.13 for 4 to 6 months, 6.1 +/- 0.21 for 7 to 12 months, and 8.4 +/- 0.31 for 13 to 32 months. Cumulative significant relief with one to three injections was 100% up to 1 to 3 months, 82% for 4 to 6 months, 21% for 7 to 12 months, and 10% after 12 months, with a mean relief of 6.5 +/- 0.76 months. There was significant improvement noted in overall health status with improvement not only in pain relief, but also with physical, functional, and psychological status, as well as return-to-work status. In conclusion, the results of this study demonstrate that medial branch blocks with local anesthetic and Sarapin, with or without steroids, are a cost effective modality of treatment, resulting in improvement in pain status, physical status, psychological status, functional status and return to work. PMID:16906173
Manchikanti, L; Pampati, V; Bakhit, C E; Rivera, J J; Beyer, C D; Damron, K S; Barnhill, R C
Arthrosis of the knee in chronic anterior laxity.
Arthrosis following rupture of the anterior cruciate ligament has been analysed in two series. The first series was derived from a review of 150 cases of reconstruction of the anterior cruciate ligament with a follow-up of 3 years or more. Arthrosis was seen to have developed in 13.3%. The second series was concerned with 64 cases of unilateral arthrosis treated by upper tibial valgus osteotomy in whom there had been a previous rupture of the anterior cruciate ligament. The 'tolerance interval'--that is the time between the original ligamentous injury and the time of osteotomy--for the development of arthrosis was very variable, ranging in the natural-history cases from 10 to 50 years, with a mean of 35 years. It is important to recognise the radiological signs of the onset of arthrosis. These are osteophytosis of the intercondylar notch, osteophyte formation at the posterior part of the medial tibial plateau, and, in particular, narrowing of the medial joint line with posterior subluxation of the medial femoral condyle, well seen in lateral radiographs whilst standing on one lower limb. Early arthroses, appearing after 10 years, may occur as a 'natural arthrosis', but it develops much more frequently after surgical treatment that had failed to correct anterior laxity and particularly when it had been performed on knees that were already pre-arthrotic. The main factor in arthrosis is anterior laxity measured radiologically by an 'active Lachman' radiograph. Removal of the medial meniscus which in itself, is liable to produce arthrosis, is even more harmful in anterior cruciate laxity since it doubles the degree of anterior subluxation of the tibia seen on unilateral weight-bearing. The development of varus deformity, which characterises progressive arthrosis, has its origin in wear of the posterior part of the medial tibial plateau caused by anterior cruciate laxity. Other factors play an important part such as associated lateral laxity, constitutional genu varum and weakness of the hamstring muscles, which oppose the subluxating action of the quadriceps. PMID:24461232
Dejour, H; Walch, G; Deschamps, G; Chambat, P
Audit of conservative management of chronic low back pain in a secondary care setting part I: facet joint and sacroiliac joint interventions
The work of a chronic back pain service in secondary care in the West Midlands is reported. The service offers acupuncture, spinal injection procedures, osteopathy and a range of other interventions for patients whose back pain has not responded to conservative management. This section of the report focuses on injection procedures for lumbar facet joint and sacroiliac joint pain, which
Robin Chakraverty; Richard Dias
Explosive growth of facet joint interventions in the medicare population in the United States: a comparative evaluation of 1997, 2002, and 2006 data
BACKGROUND: The Office of Inspector General of the Department of Health and Human Services (OIG-DHHS) issued a report which showed explosive growth and also raised questions of lack of medical necessity and\\/or indications for facet joint injection services in 2006. The purpose of the study was to determine trends of frequency and cost of facet joint interventions in managing spinal
Laxmaiah Manchikanti; Vidyasagar Pampati; Vijay Singh; Mark V Boswell; Howard S Smith; Joshua A Hirsch
The short- and mid-term effect of dynamic interspinous distraction in the treatment of recurrent lumbar facet joint pain
Owing to failure to achieve positive long-term effects, the currently performed treatment methods for lumbar facet joint syndrome (LFJS) are still under debate. Interspinous distraction devices unload the facet joints. Thus, these devices might be an alternative surgical treatment method for LFJS. The aim of this study was to evaluate the clinical and radiological outcome of an interspinous distraction device for the treatment of LFJS. Subjects had verified single level LFJS at level L45. They received percutaneous facet joint denervation (PFJD). If pain persisted, they were offered implantation of an interspinous device (Coflex) and/or repeat PFJD. Clinical and radiological outcome was determined before and after PFJD or surgery up to 2 years afterwards in all cases. Forty-one patients with LFJS at L45 underwent PFJD. Twenty patients with persisting pain underwent a subsequent surgery for implantation of an interspinous device. Five patients with recurrent pain at 612 months opted for an additional PFJD. Three obese patients (body weight >100 kg) had persistent pain at 3 months after surgery and received additionally dorsal semi-dynamic stabilization. The clinical outcome improved significantly in the surgically treated patients; however, it did not differ compared with patients receiving PFJD only after 24 months. Radiological evaluation revealed a restricted range of motion (ROM) of the operated and an elevated ROM of the adjacent segment. Surgical or device-related complications were not observed. In conclusions, the implantation of an interspinous Coflex device in case of recurrent facet joint pain succeeds to improve facet joint pain in clinical short-and mid-term settings. However, it does not exceed the outcome of denervated patients.
Abbushi, Alexander; Woiciechowsky, Christian; Kroppenstedt, Stefan
Conservative Management of a Young Adult with Hip Arthrosis
Study Design Case report Background Clinical practice guidelines regarding the conservative management of degenerative hip conditions in older adults routinely incorporate therapeutic exercise and manual therapy. However, the application of these recommendations to young, active adults is less clear. The purpose of this case report is to describe the management of a young adult with advanced hip arthrosis using a multi-faceted rehabilitation program. Case Description A 28-year old female with severe left hip degeneration per diagnostic imaging was referred to physical therapy. Reduced hip range of motion and strength, sacroiliac joint asymmetries, and a modified Harris Hip Score of 76 were observed. She was seen for 12 visits over a 3-month period and treated with an individualized program including manual therapy, therapeutic exercise, and neuromuscular re-education. Outcome Substantial improvements were noted in pain, hip range of motion and strength and function (modified Harris Hip Score of 97). In addition, she discontinued the use of anti-inflammatory medications and returned to her prior level of activity. Improvements were maintained at a 3 month follow up, with symptom recurrence managed using a self mobilization technique to the left hip and massage to the left iliopsoas. Discussion Degenerative hip conditions are common among older adults but are relatively rare in the younger population. Although it is likely that this patient will experience a return of her symptoms and functional limitations as her hip disease progresses, the immediate improvements may delay the need for eventual surgical management. These outcomes suggest that physical therapy management should be considered in those with an early onset of degenerative hip disease and are consistent with results previously reported in the older population. Level of Evidence Therapy, Level 4
Cook, Kyle M.; Heiderscheit, Bryan
Explosive growth of facet joint interventions in the medicare population in the United States: a comparative evaluation of 1997, 2002, and 2006 data
Background The Office of Inspector General of the Department of Health and Human Services (OIG-DHHS) issued a report which showed explosive growth and also raised questions of lack of medical necessity and/or indications for facet joint injection services in 2006. The purpose of the study was to determine trends of frequency and cost of facet joint interventions in managing spinal pain. Methods This analysis was performed to determine trends of frequency and cost of facet joint Interventions in managing spinal pain, utilizing the annual 5% national sample of the Centers for Medicare and Medicaid Services (CMS) for 1997, 2002, and 2006. Outcome measures included overall characteristics of Medicare beneficiaries receiving facet joint interventions, utilization of facet joint interventions by place of service, by specialty, reimbursement characteristics, and other variables. Results From 1997 to 2006, the number of patients receiving facet joint interventions per 100,000 Medicare population increased 386%, facet joint visits increased 446%, and facet joint interventions increased 543%. The increases were higher in patients aged less than 65 years compared to those 65 or older with patients increasing 504% vs. 355%, visits increasing 587% vs. 404%, and services increasing 683% vs. 498%. Total expenditures for facet joint interventions in the Medicare population increased from over $229 million in 2002 to over $511 million in 2006, with an overall increase of 123%. In 2006, there was a 26.8-fold difference in utilization of facet joint intervention services in Florida compared to the state with the lowest utilization - Hawaii. There was an annual increase of 277.3% in the utilization of facet joint interventions by general physicians, whereas a 99.5% annual increase was seen for nurse practitioners (NPs) and certified registered nurse anesthetists (CRNAs) from 2002 to 2006. Further, in Florida, 47% of facet joint interventions were performed by general physicians. Conclusions The reported explosive growth of facet joint interventions in managing spinal pain in certain regions and by certain specialties may result in increased regulations and scrutiny with reduced access.
Audit of conservative management of chronic low back pain in a secondary care setting--part I: facet joint and sacroiliac joint interventions.
The work of a chronic back pain service in secondary care in the West Midlands is reported. The service offers acupuncture, spinal injection procedures, osteopathy and a range of other interventions for patients whose back pain has not responded to conservative management. This section of the report focuses on injection procedures for lumbar facet joint and sacroiliac joint pain, which have been shown to be the cause of chronic low back pain in 16-40% and 13-19% of patients respectively. Diagnosis relies on the use of intra-articular or sensory nerve block injections with local anaesthetic. Possible treatments following diagnosis include intra-articular corticosteroid, radiofrequency denervation (for facet joint pain) or ligament prolotherapy injections (for sacroiliac joint pain). The results of several hospital audits are reported. At six month follow up, 50% of 38 patients undergoing radiofrequency denervation following diagnostic blocks for facet joint pain had improved by more than 50%, compared to 29% of 34 patients treated with intra-articular corticosteroid injection. Sixty three per cent of 19 patients undergoing prolotherapy following diagnostic block injection for sacroiliac joint pain had improved at six months, compared to 33% of 33 who had intra-articular corticosteroid. Both radiofrequency denervation and sacroiliac prolotherapy showed good long-term outcomes at one year. PMID:15628778
Chakraverty, Robin; Dias, Richard
Tensile stretching of cervical facet joint capsule and related axonal changes
This study examines axonal changes in goat cervical facet joint capsules (FJC) subjected to low rate loading. Left C5C6 FJC was subjected to a series of tensile tests from 2 mm to failure using a computer-controlled actuator. The FJC strain on the dorsal aspect was monitored by a stereo-imaging system. Stretched (n = 10) and unstretched (n = 7) capsules were harvested and serial sections were processed by a silver impregnation method. The mean peak actuator displacement was 21.3 mm (range: 1230 mm). The average peak strain encompassing various regions of the capsule was 72.9 Ý 7.1%. Complete failure of the capsule was observed in 70% of the stretched capsules. Silver impregnation of the sections revealed nerve fibers and bundles in all the regions of the capsule. A blinded analysis of digital photomicrographs of axons revealed a statistically significant number of swollen axons with non-uniform caliber in stretched FJCs. Axons with terminal retraction balls, with occasional beaded appearance or with vacuolations were also observed. Stretching the FJC beyond physiological range could result in altered axonal morphology that may be related to secondary or delayed axotomy changes similar to those seen in central nervous system injuries where axons are subjected to stretching and shearing. These may contribute to neuropathic pain and are potentially related to neck pain after whiplash events.
Singh, Anita; Lu, Ying; Chen, Chaoyang; Patwardhan, Ajit; Cavanaugh, John M.
Incorporation of Lower Neck Shear Forces to Predict Facet Joint Injury Risk in Low-Speed Automotive Rear Impacts
Lower neck shear force remains a viable candidate for a low-velocity automotive rear-impact injury criterion. Data were previously reported to demonstrate high correlations between the magnitude of lower neck shear force and lower cervical spine facet joint motions. The present study determined the ability of lower neck shear force to predict soft-tissue injury risk in simulated automotive rear impacts. Rear-impact
Brian D. Stemper; Steven G. Storvik
The diagnostic validity and therapeutic value of lumbar facet joint nerve blocks with or without adjuvant agents.
Facet joints have been described as an important source of low back pain. The value of medial branch blocks in the diagnosis of facet joint mediated pain is considered important. However, the therapeutic value of medial branch blocks has not been determined. This study was designed to evaluate the duration of relief obtained and therapeutic value following controlled medial branch blocks with or without adjuvant agents Sarapin (High Chemical Company, Levittown, PA) and Depo-medrol (Pharmacia and Upjohn Company, Kalamazoo, MI). The study population consisted of 180 consecutive patients seen in a single pain management practice, divided into three groups with 60 patients in each group. Group I was treated with local anesthetic only, Group II with the addition of Sarapin, and Group III with the addition of Depo-medrol along with Sarapin. The prevalence of facet joint pain in chronic low back pain was determined as 36%, with a false-positive rate of 25%. Comparison of duration of relief in days with each block in the three groups showed that the relief was significantly superior in Group III compared with Group I and Group II, whereas Group II was superior to Group I. PMID:10998741
Manchikanti, L; Pampati, V; Fellows, B; Bakhit, C E
Effect of changing lumbar stiffness by single facet joint dysfunction on the responsiveness of lumbar muscle spindles to vertebral movement
Objective: Individuals experiencing low back pain often present clinically with intervertebral joint dysfunction. The purpose of this study was to determine whether relative changes in stiffness at a single spinal joint alters neural responsiveness of lumbar muscle spindles to either vertebral movement or position. Methods: Muscle spindle discharge was recorded in response to 1mm L6 ramp and hold movements (0.5mm/s) in the same animal for lumbar laminectomy-only (n=23), laminectomy & L5/6 facet screw (n=19), laminectomy & L5/6 facetectomy (n=5) conditions. Mean instantaneous frequency (MIF) was calculated for the ramp-up, hold, ramp-down and post-ramp phases during each joint condition. Results: Mean MIFs were not significantly different between the laminectomy-only and the other two types of joint dysfunction for the ramp-up, hold, ramp-down, or post-ramp phases. Conclusion: Stiffness changes caused by single facet joint dysfunction failed to alter spindle responses during slow 1mm ramp and hold movements of the L6 vertebra.
Reed, William R.; Pickar, Joel G.; Long, Cynthia R.
Significance of interfacet distance, facet joint orientation, and lumbar lordosis in spondylolysis.
The aim of this study is to reveal the association between lumbar spondylolysis and several radiologic parameters, which had been suggested to be significant. The authors examine interfacet distance (IFD), facet joint orientation (FJO), and lumbar segmental lordosis (LSL) all together on the basis of lumbar computed tomography (CT) scan of 35 patients with L5 spondylolysis and 36 unaffected control groups. Thirty-five Korean military recruits, aged 19-23 (mean 20.9 years), were diagnosed as L5 spondylolysis by lumber CT scans. As a control group, 36 male Korean military recruits, aged 18-25 (mean 21.3 years), were reconfirmed as not affected by lumbar spondylolysis by CT scan when they visited our hospital complaining of back pain. This study compares IFD, FJO, and LSL for each lumbar segment between the spondylolytic and unaffected groups. We also propose the use of normal mean data of IFD, FJO, and LSL of lumbar vertebrae from 36 Korean young military recruits because each measurement has power as an absolute value, like data from an osteologic collection in other studies. Comparison of IFD between spondylolytic and unaffected individuals reveals significant differences at the L3, L4, and L5 level (P = 0.0384, P = 0.0219, and P < 0.0001, respectively). In the group of spondylolysis, the increase of IFD from L4 to S1 was less pronounced (P < 0.0001) and the LSL at L5-S1 was more lordotic (P = 0.0203). Interfacet distance and lumbar lordosis were significantly different between patients with L5 spondylolysis and individuals without pars defect on L5. In the spondylolysis group, and the increase of IFD from L4 to S1 was less pronounced and the LSL at L5-S1 was more lordotic. PMID:21815218
Chung, Sang-Bong; Lee, Sungjoon; Kim, Hoon; Lee, Sun-Ho; Kim, Eun Sang; Eoh, Whan
Osteoarthritis is one of the most common and economically important chronic diseases amongst adults, especially those of a senior age. There now exists a range of effective medications, which either alone or in combination can alleviate the symptoms of the disease and improve the quality of life. Because these medications are not always sufficiently effective and must sometimes be interrupted due to side effects, a large arsenal of active agents is necessary. Alleviation of pain and inhibition of inflammation are the primary goals of pharmacotherapy, whereby the objective is to return an active or transiently painful, decompensated osteoarthritis to a latent (silent, pain-free) condition. This therapeutic goal can almost always be accomplished by using analgesics, nonsteroidal anti-inflammatory drugs (NSAIDs), or intraarticular injection of glucocorticoids. The main problem in administering NSAIDs is their gastrointestinal toxicity,for which a prophylactic medication (e.g., simultaneous application of misoprostol or switching to a COX-2 selective NSAID) should be considered especially with risk groups. The newly developed COX-2 selective NSAIDs represent a true enrichment of our therapeutic options. The spectrum of indications for COX-2 selective NSAIDs should in the future correspond to that of older NSAID preparations, providing that no as yet unknown and serious side effects come to light from their use. Pharmacological results published until now confirm that a clinically relevant analgesic and/or anti-inflammatory effect is associated with the use of SYSA-DOAs (symptomatic slow acting drugs in osteoarthritis). However, no clinical studies exist which can positively confirm prevention of morphologically recognizable cartilage defects in man, or a slowing down or reversal of any progressively developing joint cartilage destruction by any individual medication. Neither the benefits, risks, pharmaceutical quality, nor composition of Orthokin are known, and for this reason its use can not be recommended. Pharmacotherapy should only be considered as one of the three pillars of a long-term,stage-adjusted, and individually customized therapy, the other two of which are represented by nonpharmacological measures and surgical treatment. PMID:11766630
Steinmeyer, J
Ketorolac Reduces Spinal Astrocytic Activation and PAR1 Expression Associated with Attenuation of Pain after Facet Joint Injury
Abstract Chronic neck pain affects up to 70% of persons, with the facet joint being the most common source. Intra-articular injection of the non-steroidal anti-inflammatory drug ketorolac reduces post-operative joint-mediated pain; however, the mechanism of its attenuation of facet-mediated pain has not been evaluated. Protease-activated receptor-1 (PAR1) has differential roles in pain maintenance depending on the type and location of painful injury. This study investigated if the timing of intra-articular ketorolac injection after painful cervical facet injury affects behavioral hypersensitivity by modulating spinal astrocyte activation and/or PAR1 expression. Rats underwent a painful joint distraction and received an injection of ketorolac either immediately or 1 day later. Separate control groups included injured rats with a vehicle injection at day 1 and sham operated rats. Forepaw mechanical allodynia was measured for 7 days, and spinal cord tissue was immunolabeled for glial fibrillary acidic protein (GFAP) and PAR1 expression in the dorsal horn on day 7. Ketorolac administered on day 1 after injury significantly reduced allodynia (p=0.0006) to sham levels, whereas injection immediately after the injury had no effect compared with vehicle. Spinal astrocytic activation followed behavioral responses and was significantly decreased (p=0.009) only for ketorolac given at day 1. Spinal PAR1 (p=0.0025) and astrocytic PAR1 (p=0.012) were significantly increased after injury. Paralleling behavioral data, astrocytic PAR1 was returned to levels in sham only when ketorolac was administered on day 1. Yet, spinal PAR1 was significantly reduced (p<0.0001) by ketorolac independent of timing. Spinal astrocyte expression of PAR1 appears to be associated with the maintenance of facet-mediated pain.
Dong, Ling; Smith, Jenell R.
Evaluation of Lumbar Facet Joint Nerve Blocks in Managing Chronic Low Back Pain: A Randomized, Double-Blind, Controlled Trial with a 2-Year Follow-Up
Study Design: A randomized, double-blind, controlled trial. Objective: To determine the clinical effectiveness of therapeutic lumbar facet joint nerve blocks with or without steroids in managing chronic low back pain of facet joint origin. Summary of Background Data: Lumbar facet joints have been shown as the source of chronic pain in 21% to 41% of low back patients with an average prevalence of 31% utilizing controlled comparative local anesthetic blocks. Intraarticular injections, medial branch blocks, and radiofrequency neurotomy of lumbar facet joint nerves have been described in the alleviation of chronic low back pain of facet joint origin. Methods: The study included 120 patients with 60 patients in each group with local anesthetic alone or local anesthetic and steroids. The inclusion criteria was based upon a positive response to diagnostic controlled, comparative local anesthetic lumbar facet joint blocks. Outcome measures included the numeric rating scale (NRS), Oswestry Disability Index (ODI), opioid intake, and work status, at baseline, 3, 6, 12, 18, and 24 months. Results: Significant improvement with significant pain relief of ? 50% and functional improvement of ? 40% were observed in 85% in Group 1, and 90% in Group II, at 2-year follow-up. The patients in the study experienced significant pain relief for 82 to 84 weeks of 104 weeks, requiring approximately 5 to 6 treatments with an average relief of 19 weeks per episode of treatment. Conclusions: Therapeutic lumbar facet joint nerve blocks, with or without steroids, may provide a management option for chronic function-limiting low back pain of facet joint origin.
Manchikanti, Laxmaiah; Singh, Vijay; Falco, Frank J.E.; Cash, Kimberly A.; Pampati, Vidyasagar
Axial involvement with facet joint arthropathy and bony ankylosis in a case of camptodactyly, arthropathy, coxa vara, pericarditis (CACP) syndrome.
Familial arthropathy associated with congenital camptodactyly has been previously recognized as a definite clinical entity in the literature. The clinical spectrum of this disease seems to be variable. The typical features of congenital camptodactyly, arthropathy, coxa vara and pericarditis (CACP syndrome) appear to be a more frequent presentation in children from the Middle East and North Africa. Musculoskeletal presentation of this rare familial form of arthropathy is unique and heterogeneous. In all previous reports, non-inflammatory pattern of arthropathy involving the peripheral joints with typical coxa vara deformity were described, and in a few cases spine abnormalities, including kyphosis, lordosis, or scoliosis. We describe the first case of axial involvement in a typical case of CACP syndrome with facet joint arthropathy and ankylosis at L5/S1 levels. PMID:23931850
Emad, Yasser; Ragab, Yasser; Khalifa, Maher; Bassyouni, Iman; El-Shaarawy, Nashwa; Rasker, Johannes J
The characteristics of bony ankylosis of the facet joint of the upper cervical spine in rheumatoid arthritis patients
This study investigated the bony ankylosis of the upper cervical spine facet joints in patients with a cervical spine involvement due to rheumatoid arthritis (RA) using computed tomography (CT) and then examined the characteristics of the patients showing such ankylosis. Forty-six consecutive patients who underwent surgical treatment for RA involving the cervical spine were reviewed. The radiographic diagnoses included atlanto-axial subluxation in 30 cases, vertical subluxation (VS) in 10 cases, VS + subaxial subluxation in 3 cases and cervical spondylotic myelopathy in 3 cases. The patients were classified into two groups, those developing bony ankylosis or not and then the differences in the patient characteristics between the two groups was investigated. Furthermore, cervical spine disorders and surgeries were also evaluated in patients who demonstrated such bony ankylosis. The CT reconstruction image demonstrated bony ankylosis in 12 patients (group BA), and the remaining 34 cases (group NB) showed no bony ankylosis. The level at which bony ankylosis occurred was atlanto-occipital joint (AOJ) in eight cases, atlanto-axial joint (AAJ) in two cases and AOJ, AAJ in two cases. No differences were observed between the two groups (age P > 0.54, gender P > 0.39, duration of RA P > 0.72). There was a significant difference between two groups in the patients showing obvious neurological impairment (P = 0.017). In BA group, arthrodesis or decompression was adapted for a caudal region of bony ankylosis. In conclusion, bony ankylosis of the facet joint of the upper cervical spine was detected in 12 of 46 RA patients with involvement of the cervical spine who thus required surgery. These findings showed that the patients demonstrating such ankylosis showed severe cervical myelopathy. In addition, we suggest that the occurrence of bony ankylosis was a risk factor for instability of AAJ, and subaxial instability or stenosis.
Nishinome, Masahiro; Sorimachi, Yasunori; Ara, Tsuyoshi; Nakajima, Takashi; Iizuka, Yoichi; Takagishi, Kenji
Activating transcription factor 4, a mediator of the integrated stress response, is increased in the dorsal root ganglia following painful facet joint distraction
Chronic neck pain is one of the most common musculoskeletal disorders in the US. Although biomechanical and clinical studies have implicated the facet joint as a primary source of neck pain, specific cellular mechanisms still remain speculative. The purpose of this study was to investigate whether a mediator (ATF4) of the integrated stress response (ISR) is involved in facet-mediated pain. Holtzman rats underwent C6/C7 facet joint loading that produces either painful (n=16) or nonpainful (n=8) responses. A sham group (n=9) was also included as surgical controls. Behavioral sensitivity was measured and the C6 DRGs were harvested on day 7 to evaluate the total and neuronal ATF4 expression. In separate groups, an intra-articular ketorolac injection was administered either immediately (D0 ketorolac) or 1 day (D1 ketorolac) after painful facet joint loading. Allodynia was measured at days 1 and 7 after injury to assess the effects on behavioral responses. ATF4 and BiP (an indicator of ISR activation) were separately quantified at day 7. Facet joint loading sufficient to elicit behavioral hypersensitivity produced a 3-fold increase in total and neuronal ATF4 expression in the DRG. After ketorolac treatment at the time of injury, ATF4 expression was significantly (p<0.01) reduced despite not producing any attenuation of behavioral responses. Interestingly, ketorolac treatment at day 1 significantly (p<0.001) alleviated behavioral sensitivity at day 7, but did not modify ATF4 expression. BiP expression was unchanged after either intervention time. Results suggest that ATF4-dependent activation of the ISR does not directly contribute to persistent pain, but may sensitize neurons responsible for pain initiation. These behavioral and immunohistochemical findings imply that facet-mediated pain may be sustained through other pathways of the ISR.
Dong, Ling; Guarino, Benjamin B.; Jordan-Sciutto, Kelly L.; Winkelstein, Beth A.
Brain-derived neurotrophic factor is upregulated in the cervical dorsal root ganglia and spinal cord and contributes to the maintenance of pain from facet joint injury in the rat.
The facet joint is commonly associated with neck and low back pain and is susceptible to loading-induced injury. Although tensile loading of the cervical facet joint has been associated with inflammation and neuronal hyperexcitability, the mechanisms of joint loading-induced pain remain unknown. Altered brain-derived neurotrophic factor (BDNF) levels are associated with a host of painful conditions, but the role of BDNF in loading-induced joint pain remains undefined. Separate groups of rats underwent a painful cervical facet joint distraction or a sham procedure. Bilateral forepaw mechanical hypersensitivity was assessed and BDNF mRNA and protein levels were quantified in the dorsal root ganglion (DRG) and spinal cord at days 1 and 7. Facet joint distraction induced significant (P?0.001) mechanical hypersensitivity at both time points. Painful joint distraction did not alter BDNF mRNA in the DRG compared with sham levels but did significantly increase (P?0.016) BDNF protein expression over sham in the DRG at day 7. Painful distraction also significantly increased BDNF mRNA (P?=?0.031) and protein expression (P?=?0.047) over sham responses in the spinal cord at day 7. In a separate study, intrathecal administration of the BDNF-sequestering molecule trkB-Fc on day 5 after injury partially attenuated behavioral sensitivity after joint distraction and reduced pERK in the spinal cord at day 7 (P?0.045). Changes in BDNF after painful facet joint injury and the effect of spinal BDNF sequestration in partially reducing pain suggest that BDNF signaling contributes to the maintenance of loading-induced facet pain but that additional cellular responses are also likely involved. PMID:23918351
Kras, Jeffrey V; Weisshaar, Christine L; Quindlen, Julia; Winkelstein, Beth A
Effect of multilevel lumbar disc arthroplasty on spine kinematics and facet joint loads in flexion and extension: a finite element analysis.
Total disc arthroplasty (TDA) has been successfully used for monosegmental treatment in the last few years. However, multi-level TDA led to controversial clinical results. We hypothesise that: (1) the more artificial discs are implanted, the stronger the increases in spinal mobility and facet joint forces in flexion and extension; (2) deviations from the optimal implant position lead to strong instabilities. A three-dimensional finite element model of the intact L1-L5 human lumbar spine was created. Additionally, models of the L1-L5 region implanted with multiple CharitÕ discs ranging from two to four levels were created. The models took into account the possible misalignments in the antero-posterior direction of the artificial discs. All these models were exposed to an axial compression preload of 500 N and pure moments of 7.5 Nm in flexion and extension. For central implant positions and the loading case extension, a motion increase of 51% for two implants up to 91% for four implants and a facet force increase of 24% for two implants up to 38% for four implants compared to the intact spine were calculated. In flexion, a motion decrease of 5% for two implants up to 8% for four implants was predicted. Posteriorly placed implants led to a better representation of the intact spine motion. However, lift-off phenomena between the core and the implant endplates were observed in some extension simulations in which the artificial discs were anteriorly or posteriorly implanted. The more artificial discs are implanted, the stronger the motion increase in flexion and extension was predicted with respect to the intact condition. Deviations from the optimal implant position lead to unfavourable kinematics, to high facet joint forces and even to lift-off phenomena. Therefore, multilevel TDA should, if at all, only be performed in appropriate patients with good muscular conditions and by surgeons who can ensure optimal implant positions. PMID:20361341
Schmidt, Hendrik; Galbusera, Fabio; Rohlmann, Antonius; Zander, Thomas; Wilke, Hans-Joachim
Symptomatic anterior subtalar arthrosis after ankle arthrodesis.
A 76-year-old man reported right lateral heel pain 11?years after ankle arthrodesis. Clinically, there was tenderness in the right sinus tarsi and over the junction point between the talonavicular and calcaneocuboid joints. Radiographs showed that the joint spaces of the posterior subtalar joint and the talonavicular joint were preserved although there were osteophytes at both joints. Arthroscopic findings showed degeneration of the anterior subtalar and talonavicular joints. The symptoms subsided after arthroscopic debridement. PMID:24825553
Lui, Tun Hing
Transverse Process and Needles of Medial Branch Block to Facet Joint as Landmarks for Ultrasound-Guided Selective Nerve Root Block
Background Selective lumbar nerve root block (SNRB) is generally accepted as an effective treatment method for back pain with sciatica. However, it requires devices producing radioactive materials such as C-arm fluoroscopy. This study evaluated the usefulness of the longitudinal view of transverse process and needles for medial branch block as landmarks under ultrasonography. Methods We performed selective nerve root block for 96 nerve roots in 61 patients under the guidance of ultrasound. A curved probe was used to identify the facet joints and transverse processes. Identifying the lumbar nerve roots under the skin surface and ultrasound landmarks, the cephalad and caudal medial branch blocks were undertaken under the transverse view of sonogram first. A needle for nerve root block was inserted between the two transverse processes under longitudinal view, while estimating the depth with the needle for medial branch block. We then injected 1.0 mL of contrast medium and checked the distribution of the nerve root with C-arm fluoroscopy to evaluate the accuracy. The visual analog scale (VAS) was used to access the clinical results. Results Seven SNRBs were performed for the L2 nerve root, 15 for L3, 49 for L4, and 25 for L5, respectively. Eighty-six SNRBs (89.5%) showed successful positioning of the needles. We failed in the following cases: 1 case for the L2 nerve root; 2 for L3; 3 for L4; and 4 for L5. The failed needles were positioned at wrong leveled segments in 4 cases and inappropriate place in 6 cases. VAS was improved from 7.6 Ý 0.6 to 3.5 Ý 1.3 after the procedure. Conclusions For SNRB in lumbar spine, the transverse processes under longitudinal view as the ultrasound landmark and the needles of medial branch block to the facet joint can be a promising guidance.
Kim, Daehee; Choi, Donghyuk; Kim, Chungyoung; Kim, Jeongseok
Lumbar facet pain: biomechanics, neuroanatomy and neurophysiology.
Idiopathic low back pain has confounded health care practitioners for decades. Although there has been much advance in the understanding of the biomechanics of the lumbar spine over the past 25 years, the cellular and neural mechanisms that lead to facet pain are not well understood. An extensive series of experiments was undertaken to help elucidate these mechanisms and gain a better understanding of lumbar facet pain. Biomechanic and neuroanatomic studies were performed in human cadaveric facet joints and neurophysiologic studies were performed in New Zealand White rabbits. These studies provide the following evidence to help explain the mechanisms of lumbar facet pain: (1) The facet joint can carry a significant amount of the total compressive load on the spine when the human spine is hyperextended. (2) Extensive stretch of the human facet joint capsule occurs when the spine is in the physiologic range of extreme extension. (3) An extensive distribution of small nerve fibers and free and encapsulated nerve endings exists in the lumbar facet joint capsule, including nerves containing substance P, a putative neuromodulator of pain. (4) Low and high threshold mechanoreceptors fire when the facet joint capsule is stretched or is subject to localized compressive forces. (5) Sensitization and excitation of nerves in facet joint and surrounding muscle occur when the joint is inflamed or exposed to certain chemicals that are released during injury and inflammation. (6) Marked reduction in nerve activity occurs in facet tissue injected with hydrocortisone and lidocaine. Thus, the facet joint is a heavily innervated area that is subject to high stress and strain. The resulting tissue damage or inflammation is likely to cause release of chemicals irritating to the nerve endings in these joints, resulting in low back pain. PMID:8872268
Cavanaugh, J M; Ozaktay, A C; Yamashita, H T; King, A I
Degenerative Joint Disease in Female Ballet Dancers
The relationship between long-term ballet dancing and eventual arthrosis of the hip, ankle, subtalar, and first metatarsophalangeal joint was examined in 19 former professional female dancers, aged 50 to 70 years. The dancers were compared with pair-matched controls. All 38 women underwent medical history taking, clinical ex amination, and roentgenography of the joints studied. The roentgenographs were independently judged by
C. Niek van Dijk; Liesbeth S. L. Lim; Alina Poortman; Ernst H. Str■bbe; Rene K. Marti
Morphometric analyses of the cervical superior facets and implications for facet dislocation
The articular facets of the cervical spine have been well addressed; however, little information is available on the relationship of the superior facets of the cervical spine to traumatic dislocation in the literature. Morphometric analyses of the superior facets of 30 dried cervical spines from C3 to C7 were performed to determine any morphological differences. The angle of the superior facet with respect to the transverse plane was also measured on computed tomography (CT) scans of 30 patients having neck injury without fracture/dislocation. The vertical and surface lengths of the superior facet were significantly lower (P?0.01) at C6C7 levels than at C35 levels. The anteroposterior diameter of the superior facet was smaller (P?0.05) at C6 and C7 levels compared to C35 levels. Although the superior facet joint surface is in a more coronal orientation in lower cervical vertebrae, the inclination of the superior facet is more horizontal relative to the transverse plane when measured in vivo. A combination of lower height, smaller anteroposterior diameter of the superior facet, and a more horizontally oriented superior facet at C6 and C7 levels in vivo may explain the predilection of translation relative to one another in the lower cervical spine.
Ebraheim, Nabil A.; Patil, Vishwas; Haman, Steve P.; Yeasting, Richard A.
Endoscopic Facet Debridement for the treatment of facet arthritic pain - a novel new technique
Study design: Retrospective, observational, open label. Objective: We investigated the efficacy of facet debridement for the treatment of facet joint pain. Summary of background data: Facet joint disease, often due to degenerative arthritis, is common cause of chronic back pain. In patients that don't respond to conservative measures, nerve ablation may provide significant improvement. Due to the ability of peripheral nerves to regenerate, ablative techniques of the dorsal nerve roots often provide only temporary relief. In theory, ablation of the nerve end plates in the facet joint capsule should prevent reinnervation. Methods: All patients treated with endoscopic facet debridement at our clinic from 2003-2007 with at least 3 years follow-up were included in the analysis. Primary outcome measure was percent change in facet-related pain as measured by Visual Analog Scale (VAS) score at final follow-up visit. Results: A total of 174 people (77 women, 97 men; mean age 64, range 22-89) were included. Location of facet pain was cervical in 45, thoracic in 15, and lumbar in 114 patients. At final follow-up, 77%, 73%, and 68% of patients with cervical, thoracic, or lumbar disease, respectively, showed at least 50% improvement in pain. Mean operating time per joint was 17 minutes (range, 10-42). Mean blood loss was 40 ml (range, 10-100). Complications included suture failure in two patients, requiring reclosure of the incision. No infection or nerve damage beyond what was intended occurred. Conclusions: Our results demonstrate a comparable efficacy of endoscopic facet debridement compared to radiofrequency ablation of the dorsal nerve branch, with durable results. Large scale, randomized trials are warranted to further evaluate the relative efficacy of this surgical treatment in patients with facet joint disease.
Haufe, Scott M.W.; Mork, Anthony R.
Evaluation of the first metacarpal proximal facet inclination as a prognostic predictor following arthroplasty for osteoarthritis of the thumb carpometacarpal joint.
We have retrospectively reviewed 17 thumbs in 16 patients with osteoarthritis of the thumb carpometacarpal joints, for which arthroplasty was performed using Kaarela's method. Postoperatively, three thumbs in two patients had poor outcomes; both patients had a sharp slope of the base of the first metacarpal. Serial radiographic measurements suggested that this sharp slope affected the adducted position of the first metacarpal, and led to the appearance of a metacarpophalangeal joint hyperextension deformity of the thumb. This radiological finding could be a prognostic predictor after surgery for osteoarthritis of the thumb carpometacarpal joint. PMID:23413854
Tonogai, Ichiro; Hamada, Yoshitaka; Hibino, Naohito
Morphologische Verðnderungen der synovialen Gelenkkapselanteile bei Arthrosis deformans
Morphological investigations of the joint capsules in osteoarthrotic-changed joints have given rise to doubts about the present theory of the causal aetiology of the osteoarthrosis. In every inspected and demonstrated illustration beside the partly normal capsules segments could be found every transition between mild regressive alterations and most massiv proliferative changes of the conective tissue and the lining cell layer.
N. Dettmer; B. Barz
Calcified cartilage morphometry and its relation to subchondral bone remodeling in equine arthrosis
The calcified layer of articular cartilage is known to be affected by age and mechanical factors that may play a role in the development of arthrosis. Because these factors are also related to subchondral remodeling and sclerosis, a morphometric study was carried out in fluorochrome-labeled animals to determine whether the level of subchondral remodeling affected the thickness of the calcified
R. W Norrdin; C. E Kawcak; B. A Capwell; C. W McIlwraith
Frequency of successful intra-articular puncture of finger joints: influence of puncture position and physician experience
Objective. Physicians and specialists routinely perform IA punctures and injections on patients with joint injuries, chronic arthritis and arthrosis to release joint effusion or to inject drugs. The purpose of this study was to investigate the frequencies of intra- and peri-articular cannula positioning during this procedure. Methods. A total of 300 cadaveric finger joints were injected with a methyl blue-containing
W. Pichler; W. Grechenig; S. Grechenig; F. Anderhuber; H. Clement; A. M. Weinberg
ERIC Educational Resources Information Center
Subjectification, as the diachronic facet of subjectivity, has raised in the last two decades a number of interesting questions in grammaticalization and semantic change theory. In this paper I shall reflect on the nature and construal of subjectification, focusing on the question, formulated by Traugott (2010a, p. 58), "whether it is possible to
Visconti, Jacqueline
FACET, the Facility for Advanced Accelerator and Experimental Tests, is a new facility being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration beginning in summer 2011. The nominal FACET parameters are 23GeV, 3nC electron bunches compressed to about 20 {micro}m long and focussed to about 10 {micro}m wide. Characterization of the beam-plasma interaction requires complete knowledge of the incoming beam parameters on a pulse-to-pulse basis. FACET diagnostics include Beam Position Monitors, Toroidal current monitors, X-ray and Cerenkov based energy spectrometers, optical transition radiation (OTR) profile monitors and coherent transition radiation (CTR) bunch length measurement systems. The compliment of beam diagnostics and their expected performance are reviewed. Beam diagnostic measurements not only provide valuable insights to the running and tuning of the accelerator but also are crucial for the PWFA experiments in particular. Beam diagnostic devices are being set up at FACET and will be ready for beam commissioning in summer 2011.
Li, S.Z.; Hogan, M.J.; /SLAC
Nanodomain faceting in ferroelectrics
We show that after long times (24 h), individual circular domains in 50 nm thick (001) epitaxial films of ferroelectric lead zirconate titanate (PZT) develop facets due to the crystalline anisotropy, e.g. along (100) directions. This appears to be a creep process (Tybell et al 2002 Phys. Rev. Lett.89 097601; Paruch et al 2006 J. Appl. Phys. 100 051608) and
Facet First Beam Commissioning.
National Technical Information Service (NTIS)
The FACET (Facility for Advanced aCcelerator Experimental Tests) facility at SLAC has been under Construction since summer 2010. Its goal is to produce ultrashort and transversely small bunches of very high intensity (20kA peak current) to facilitate adva...
C. Clarke F. J. Decker G. White G. Yocky H. Smith J. Nelson J. Seeman J. Sheppard J. Turner M. Hogan M. Stanek M. H. Wang N. Lipkowitz P. Schuh S. Weathersby T. Smith W. Colocho Y. Sun
Fixation of total hip components in rheumatoid arthritis and arthrosis. A radiographic, roentgen stereophotogrammetric, densitometric and histomorphometric study.
National Technical Information Service (NTIS)
The radiographic survival of the Charnley prosthesis was studied in two retrospective, matched-pair cohorts of rheumatoid arthritis (RA) and arthrosis (OA) patients. In RA, the 7-year radiographic socket survival improved from 87% to 96% after the introdu...
I. Oensten
Grain boundary finite length faceting
We study symmetrical and asymmetrical aluminium grain boundary faceting with molecular dynamics simulations employing two embedded atom method potentials. Facet formation, coarsening, and the reversible phase transition of ?3{110} boundary into ?3{112} twin, and vice versa, are demonstrated in the simulations and the results are consistent with earlier experimental studies and theoretical models. The ?11{002}1\\/{667}2 boundary shows faceting into {225}1\\/{441}2
Z. X. Wu; Y. W. Zhang; D. J. Srolovitz
FACET is a new facility under construction at the SLAC National Accelerator Laboratory. The FACET beam line is designed to provide 23 GeV tightly focused and compressed electron and positron bunches for beam driven plasma wakefield acceleration research and other experiments. Achieving optimal beam parameters for various experimental conditions requires the optics capability for tuning in a sufficiently wide range. This will be achieved by using optics tuning systems (knobs). Design of such systems for FACET is discussed.
Nosochkov, Yuri; Hogan, Mark J.; Wittmer, Walter; /SLAC
Hip arthrosis and surgical intervention: what and when?
Osteoarthritis of the hip is a common pathology and involves forms of disability and need for treatments that affect the quality of life of patients and their families, and in general of the whole society. It should be considered as such degenerative joint disease is increasing as the increase in life expectancy and musculoskeletal trauma, the latter responsible for secondary forms of osteoarthritis. The treatment of osteoarthritis of the hip has changed a lot over the years, since the earlier diagnosis and, before, with prevention through proper lifestyle. More in-depth knowledge of the biology of the tissues involved, first of all hyaline cartilage, has lead to non-surgical treatments such as infiltration with hyaluronic acid (viscosupplementation) and autologous growth factors derived from platelets (platelet rich plasma). Surgical therapy with prosthetic replacement is finally a choice to share with the patient based on pain and functional limitation, bearing in mind always the best technology and tribology and the possibility of less invasive surgical access, while recognizing that there are not still eternal prosthesis. Of particular importance then is the age of the patient. There are also other types of surgery (hip arthroscopy, forage) for other pathologies of the hip which can be resolutive, or, in a sense, can delay the arrival to the prosthetic replacement. We will discuss below the decision-making process that leads the surgeon with the patient to the surgery option. PMID:23858310
Innocenti, Massimo; Nistri, Lorenzo; Biondi, Marco; Del Prete, Armando; Giorgini, Marco; Macera, Armando; Soderi, Stefano
Hip arthrosis and surgical intervention: what and when?
Summary Osteoarthritis of the hip is a common pathology and involves forms of disability and need for treatments that affect the quality of life of patients and their families, and in general of the whole society. It should be considered as such degenerative joint disease is increasing as the increase in life expectancy and musculoskeletal trauma, the latter responsible for secondary forms of osteoarthritis. The treatment of osteoarthritis of the hip has changed a lot over the years, since the earlier diagnosis and, before, with prevention through proper lifestyle. More in-depth knowledge of the biology of the tissues involved, first of all hyaline cartilage, has lead to non-surgical treatments such as infiltration with hyaluronic acid (viscosupplementation) and autologous growth factors derived from platelets (platelet rich plasma). Surgical therapy with prosthetic replacement is finally a choice to share with the patient based on pain and functional limitation, bearing in mind always the best technology and tribology and the possibility of less invasive surgical access, while recognizing that there are not still eternal prosthesis. Of particular importance then is the age of the patient. There are also other types of surgery (hip arthroscopy, forage) for other pathologies of the hip which can be resolutive, or, in a sense, can delay the arrival to the prosthetic replacement. We will discuss below the decision-making process that leads the surgeon with the patient to the surgery option.
Innocenti, Massimo; Nistri, Lorenzo; Biondi, Marco; Del Prete, Armando; Giorgini, Marco; Macera, Armando; Soderi, Stefano
SLAC Linac Preparations for FACET
The SLAC 3km linear electron accelerator has been cut at the two-thirds point to provide beams to two independent programs. The last third provides the electron beam for the Linac Coherent Light Source (LCLS), leaving the first two-thirds available for FACET, the new experimental facility for accelerator science and test beams. In this paper, we describe this separation and projects to prepare the linac for the FACET experimental program.
Erickson, R.; Bentson, L.; Kharakh, D.; Owens, A.; Schuh, P.; Seeman, J.; Sheppard, J.C.; Stanek, M.; Wittmer, W.; Yocky, G.; Wienands, U.; /SLAC
Faceting of twin tips in polysilicon films
NASA Astrophysics Data System (ADS)
The faceting of tips of twin plates in the interior of grains under annealing in phosphorus-doped polysilicon films, produced by low-pressure chemical vapor deposition, has been investigated by transmission electron microscopy. It has been shown that the facet types and number of facets depend on the annealing temperature. The stability diagram for the different facet types has been constructed. Three kinds of faceting transitions that take place on the twin tips have been studied. The transformation of curved grain boundary into a grain boundary facet with increasing temperature has been observed for the first time.
Nakhodkin, N. G.; Kulish, N. P.; Rodionova, T. V.
Plasma Wakefield Experiments at FACET
FACET, the Facility for Advanced Accelerator and Experimental Tests, is a new facility being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration beginning in summer 2011. The nominal FACET parameters are 23GeV, 3nC electron bunches compressed to {approx}20{micro}m long and focused to {approx}10{micro}m wide. The intense fields of the FACET bunches will be used to field ionize neutral lithium or cesium vapor produced in a heat pipe oven. Previous experiments at the SLAC FFTB facility demonstrated 50GeV/m gradients in an 85cm field ionized lithium plasma where the interaction distance was limited by head erosion. Simulations indicate the lower ionization potential of cesium will decrease the rate of head erosion and increase single stage performance. The initial experimental program will compare the performance of lithium and cesium plasma sources with single and double bunches. Later experiments will investigate improved performance with a pre-ionized cesium plasma. The status of the experiments and expected performance are reviewed. The FACET Facility is being constructed in sector 20 of the SLAC linac primarily to study beam driven plasma wakefield acceleration. The facility will begin commissioning in summer 2011 and conduct an experimental program over the coming five years to study electron and positron beam driven plasma acceleration with strong wake loading in the non-linear regime. The FACET experiments aim to demonstrate high-gradient acceleration of electron and positron beams with high efficiency and negligible emittance growth.
Hogan, M.J.; England, R.J.; Frederico, J.; Hast, C.; Li, S.Z.; Litos, M.; Walz, D.; /SLAC; An, W.; Clayton, C.E.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.; Tochitsky, S.; /UCLA; Muggli, P.; Pinkerton, S.; Shi, Y.; /Southern California U.
Modelling diffraction by facetted particles
NASA Astrophysics Data System (ADS)
A method to approximate azimuthally resolved light scattering patterns and phase functions due to diffraction and external reflection by strongly absorbing facetted particles is demonstrated for a cube and compared with results from an exact method, T-matrix. A phase function averaged over a range of orientations of a strongly absorbing hexagonal column of aspect ratio unity has been calculated and tested against Discrete Dipole Approximation (DDA) results for a size parameter of 50.
Hesse, E.; Macke, A.; Havemann, S.; Baran, A. J.; Ulanowski, Z.; Kaye, P. H.
Design of a lattice-based faceted classification system
NASA Technical Reports Server (NTRS)
We describe a software reuse architecture supporting component retrieval by facet classes. The facets are organized into a lattice of facet sets and facet n-tuples. The query mechanism supports precise retrieval and flexible browsing.
Eichmann, David A.; Atkins, John
Efficacy of Ultrasonography-Guided Injections in Patients with Facet Syndrome of the Low Lumbar Spine
Objective To investigate the efficacy of ultrasonography (US)-guided injections in patients with low lumbar facet syndrome, compared with that in patients who received fluoroscopy (FS)-guided injections. Method Fifty-seven subjects with facet syndrome of the lumbar spine of the L4-5 and L5-S1 levels were randomly divided into two groups to receive intraarticular injections into the facet joint. One group received FS-guided facet joint injections and the other group received US-guided facet joint injections. Treatment effectiveness was assessed using a visual analogue scale (VAS), physician's and patient's global assessment (PhyGA, PaGA), and the modified Oswestry Disability Index (MODI). All parameters were evaluated four times: before injections, and at a week, a month, and three months after injections. We also measured, in both groups, how long it took to complete the whole procedure. Results Each group showed significant improvement from the facet joint injections on the VAS, PhyGA, PaGA, and MODI (p<0.05). However at a week, a month, and three months after injections, no significant differences were observed between the groups with regard to VAS, PhyGA, PaGA, and MODI (p>0.05). Statistically significant differences in procedure time were observed between groups (FS: 248.7Ý6.5 sec; US: 263.4Ý5.9 sec; p=0.023). Conclusion US-guided injections in patients with lumbar facet syndrome are as effective as FS-guided injections for pain relief and improving activities of daily living.
Yun, Dong Hwan; Kim, Hee-Sang; Yoo, Seung Don; Kim, Dong Hwan; Chon, Jinn Man; Choi, Seong He; Hwang, Dae Gyu
Solitary Epidural Lipoma with Ipsilateral Facet Arthritis Causing Lumbar Radiculopathy
A 55-year-old obese man (body mass index, 31.6 kg/m2) presented radiating pain and motor weakness in the left leg. Magnetic resonance imaging showed an epidural mass posterior to the L5 vertebral body, which was isosignal to subcutaneous fat and it asymmetrically compressed the left side of the cauda equina and the exiting left L5 nerve root on the axial T1 weighted images. Severe arthritis of the left facet joint and edema of the bone marrow regarding the left pedicle were also found. As far as we know, there have been no reports concerning a solitary epidural lipoma combined with ipsilateral facet arthorsis causing lumbar radiculopathy. Solitary epidural lipoma with ipsilateral facet arthritis causing lumbar radiculopathy was removed after the failure of conservative treatment. After decompression, the neurologic deficit was relieved. At a 2 year follow-up, motor weakness had completely recovered and the patient was satisfied with the result. We recommend that a solitary epidural lipoma causing neurologic deficit should be excised at the time of diagnosis.
Kim, Hong Kyun; Koh, Sung Hye
Relationship of Facet Tropism with Degeneration and Stability of Functional Spinal Unit
Purpose The authors investigated the effect of lumbar facet tropism (FT) on intervertebral disc degeneration (DD), facet joint degeneration (FJD), and segmental translational motion. Materials and Methods Using kinetic MRI (KMRI), lumbar FT, which was defined as a difference in symmetry of more than 7¯ between the orientations of the facet joints, was investigated in 900 functional spinal units (300 subjects) in flexion, neutral, and extension postures. Each segment at L3-L4, L4-L5, and L5-S1 was assessed based on the extent of DD (grade I-V) and FJD (grade 1-4). According to the presence of FT, they were classified into two groups; one with FT and one with facet symmetry. For each group, demographics, DD, FJD and translational segmental motion were compared. Results The incidence of FT was 34.5% at L3-L4, 35.1% at L4-L5, and 35.2% at L5-S1. Age and gender did not show any significant relationship with FT. Additionally, no correlation was observed between DD and FT. FT, however, wasfound to be associated with a higher incidence of highly degenerated facet joints at L4-L5 when compared to patients without FT (p < 0.01). Finally, FT was not observed to have any effects upon translational segmental motion. Conclusion No significant correlation was observed between lumbar FT and DD or translational segmental motion. However, FT was shown to be associated significantly with the presence of high grades of FJD at L4-L5. This suggests that at active sites of segmental motion, FT may predispose to the development of facet joint degeneration.
He, Wubing; Tsai, Yu-Duan; Chen, Nan-Fu; Keorochana, Gun; Do, Duc H.; Wang, Jeffrey C.
New formula for semiconductor laser facet reflectivity
A new analytic expression for the main mode reflectivity of a multicoated laser facet at normal incidence is derived using the free space radiation mode technique. This uses exact guided modes, and accurately models the radiation modes near the facet. The results compare favorably with exact TE and TM bench marks while retaining the simplicity and speed of the Fresnel approximations.
Kendall, P.C.; Roberts, D.A.; Robson, P.N. (Univ. of Sheffield (United Kingdom)); Adams, M.J.; Robertson, M.J. (BT Labs., Martlesham Heath, Ipswich (United Kingdom))
Synovial cyst of a cervical facet joint: case report.
Intraspinal synovial cysts are rare. Those reported have occurred in the lumbar region. We report a case of an extradural true synovial cyst of the cervical spine causing spastic paraparesis. The cyst occurred after a cervical spine fracture and, hence, was probably related to trauma. Surgical therapy resulted in a satisfactory recovery. PMID:4010912
Cartwright, M J; Nehls, D G; Carrion, C A; Spetzler, R F
Method for partially coating laser diode facets
NASA Technical Reports Server (NTRS)
Bars of integral laser diode devices cleaved from a wafer are placed with their p regions abutting and n regions abutting. A thin BeCu mask having alternate openings and strips of the same width as the end facets is used to mask the n region interfaces so that multiple bars can be partially coated over their exposed p regions with a reflective or partial reflective coating. The partial coating permits identification of the emitting facet from the fully coated back facet during a later device mounting procedure.
Dholakia, Anil R. (Inventor)
The Validation of Ultrasound-Guided Lumbar Facet Nerve Blocks as Confirmed by Fluoroscopy
Study Design This is a prospective study. Purpose To develop a methodological approach for conducting ultrasound-guided lumbar facet nerve block by defining essential ultrasound-guided landmarks in order to assess the feasibility of this method. Overview of Literature The current role of ultrasound guidance for musculoskeletal intervention treatments has been reported upon in previous literature. Methods Ultrasound-guided facet nerve block was done in 95 segments for 50 patients with chronic back pain by facet arthropathy. After the surface landmarks of the spinous process and iliac crest line were confirmed, longitudinal facet views were obtained by a curved array transducer to identify the different spinal segments. The spinous process and facet joint with transverse process were delineated by transverse sonograms at each level and the target point for the block was defined as lying on the upper edge of the transverse process. The needle was inserted toward the target point. After a contrast injection, the placement of the needle and contrast was checked by fluoroscopy. Results Eighty-seven segments (91.6%) could be guided successfully to the right facet nerve block by using ultrasound. After fluoroscopic control, 8 needles had to be corrected because of problems with other segments (3 cases) and lamina placements (5 cases). For the 42 patients who underwent successful block by ultrasound, however, the mean visual analogue score for back pain was improved from 6.2 Ý 0.9 before the block to 4.0 Ý 1.0 after the block (p = 0.001). Conclusions Ultrasound-guided longitudinal facet view and the surface landmarks of the spinous process and iliac crest line seems to be a promising guidance technique for the lumbar facet nerve block technique.
Jung, Heunguyn; Jeon, Seonghun; Ahn, Sangho; Kim, Minwook
The clinical aspects of the acute facet syndrome: results from a structured discussion among European chiropractors
Background The term 'acute facet syndrome' is widely used and accepted amongst chiropractors, but poorly described in the literature, as most of the present literature relates to chronic facet joint pain. Therefore, research into the degree of consensus on the subject amongst a large group of chiropractic practitioners was seen to be a useful contribution. Methods During the annual congress of The European Chiropractors Union (ECU) in 2008, the authors conducted a workshop involving volunteer chiropractors. Topics were decided upon in advance, and the participants were asked to form into groups of four or five. The groups were asked to reach consensus on several topics relating to a basic case of a forty-year old man, where an assumption was made that his pain originated from the facet joints. First, the participants were asked to agree on a maximum of three keywords on each of four topics relating to the presentation of pain: 1. location, 2. severity, 3. aggravating factors, and 4. relieving factors. Second, the groups were asked to agree on three orthopaedic and three chiropractic tests that would aid in diagnosing pain from the facet joints. Finally, they were asked to agree on the number, frequency and duration of chiropractic treatment. Results Thirty-four chiropractors from nine European countries participated. They described the characteristics of an acute, uncomplicated facet syndrome as follows: local, ipsilateral pain, occasionally extending into the thigh with pain and decreased range of motion in extension and rotation both standing and sitting. They thought that the pain could be relieved by walking, lying with knees bent, using ice packs and taking non-steroidal anti-inflammatory drugs, and aggravated by prolonged standing or resting. They also stated that there would be no signs of neurologic involvement or antalgic posture and no aggravation of pain from sitting, flexion or coughing/sneezing. Conclusion The chiropractors attending the workshop described the characteristics of an acute, uncomplicated lumbar facet syndrome in much the same way as chronic pain from the facet joints has been described in the literature. Furthermore, the acute, uncomplicated facet syndrome was considered to have an uncomplicated clinical course, responding quickly to spinal manipulative therapy.
Hestbaek, Lise; Kongsted, Alice; Jensen, Tue Secher; Leboeuf-Yde, Charlotte
FACET: SLAC___s New User Facility
FACET (Facility for Advanced Accelerator Experimental Tests) is a new User Facility at SLAC National Accelerator Laboratory. The first User Run started in spring 2012 with 20 GeV, 3 nC electron beams. The facility is designed to provide short (20 {micro}m) bunches and small (20 {micro}m wide) spot sizes, producing uniquely high power beams. FACET supports studies from many fields but in particular those of Plasma Wakefield Acceleration and Dielectric Wakefield Acceleration. The creation of drive and witness bunches and shaped bunch profiles is possible with 'Notch' Collimation. FACET is also a source of THz radiation for material studies. Positrons will be available at FACET in future user runs. We present the User Facility and the available tools and opportunities for future experiments.
Clarke, C.I.; Decker, F.-J.; England, R.J.; Erickson, R.A.; Hast, C.; Hogan, M.J.; Li, S.Z.; Litos, M.D.; Nosochkov, Y.; Seeman, J.T.; Sheppard, J.; Wienands, U.; Woodley, M.; Yocky, G.; /SLAC
Stress radiographs in the evaluation of degenerative femorotibial joint disease.
Thirty-eight osteoarthrotic knees were examined to assess the widths of the femorotibial joint spaces. Radiographs were exposed with the patient lying, in a standing position, and with an adduction and abduction force. Forced compression of the osteoarthrotic joint compartment caused, on average, 18% greater narrowing than when loading it in the standing position. Compared to the joint space at rest, the non-weight-bearing compartment widened by 16% in the standing position and narrowed by 20% when stress was applied. Furthermore, the results showed an increase in laxity proportional to the degree of arthrosis. Stress radiographs significantly display the real cartilage width of both joint compartments. Knowledge of the condition of the articular cartilage in the non-weight-bearing compartment is important when considering a transfer of loading stresses by means of osteotomy. PMID:3423831
Tallroth, K; Lindholm, T S
FACET: SLAC___s New User Facility
FACET (Facility for Advanced Accelerator Experimental Tests) is a new User Facility at SLAC National Accelerator Laboratory. The first User Run started in spring 2012 with 20 GeV, 3 nC electron beams. The facility is designed to provide short (20 ö¥m) bunches and small (20 ö¥m wide) spot sizes, producing uniquely high power beams. FACET supports studies from many fields
Results from Plasma Wakefield Experiments at FACET
We report initial results of the Plasma Wakefield Acceleration (PWFA) Experiments performed at FACET - Facility for Advanced aCcelertor Experimental Tests at SLAC National Accelerator Laboratory. At FACET a 23 GeV electron beam with 1.8 x 10¿¯ electrons is compressed to 20 m longitudinally and focused down to 10 m x 10 m transverse spot size for user driven experiments.
S. Z. Li; C. I. Clarke; R. J. England; J. Frederico; S. J. Gessner; M. J. Hogan; R. K. Jobe; M. D. Litos; D. R. Walz; P. Muggli; W. An; C. E. Clayton; C. Joshi; W. Lu; K. A. Marsh; W. Mori; S. Tochitsky; E. Adli
The instant axis of rotation influences facet forces at L5/S1 during flexion/extension and lateral bending.
Because the disc and facets work together to constrain spinal kinematics, changes in the instant axis of rotation associated with disc degeneration or disc replacement may adversely influence risk for facet overloading and arthritis. The relationships between L5/S1 segmental kinematics and facet forces are not well defined, since previous studies have separated investigations of spinal motion and facet force. The goal of this cadaveric biomechanical study was to report and correlate a measure of intervertebral kinematics (the centrode, or the path of the instant axis of rotation) and the facet forces at the L5/S1 motion segment while under a physiologic combination of compression and anterior shear loading. Twelve fresh-frozen human cadaveric L5/S1 joints (age range 50-64 years) were tested biomechanically under semi-constrained conditions by applying compression plus shear forces in several postures: neutral, and 3 degrees and 6 degrees of flexion, extension and lateral bending. The experimental boundary conditions imposed compression and shear representative of in vivo conditions during upright stance. The 3-D instantaneous axis of rotation (IAR) was calculated between two consecutive postures. The facet joint force was simultaneously measured using thin-film sensors placed between both facet surfaces. Variations of IAR location and facet force during motion were analyzed. During flexion and extension, the IAR was oriented laterally. The IAR intersection with the mid-sagittal plane moved cephalad relative to S1 endplate during flexion (P=0.010), and posterior during extension (P=0.001). The facet force did not correlate with posture (P=0.844). However, changes in the facet force between postures did correlate with IAR position: higher IAR's during flexion correlated with lower facet forces and vice versa (P=0.04). During lateral bending, the IAR was oblique relative to the main plane of motion and translated parallel to S1 endplate, toward the side of the bending. Overall, the facet force was increased on the ipsilateral side of bending (P=0.002). The IAR positions demonstrate that the L5 vertebral body primarily rotates forward during flexion (IAR close to vertebral body center) and rotates/translates backward during extension (IAR at or below the L5/S1 intervertebral disc). In lateral bending, the IAR obliquity demonstrated coupling with axial torsion due to resistance of the ipsilateral facet. PMID:16175392
Rousseau, Marc-Antoine; Bradford, David S; Hadi, Tamer M; Pedersen, Kirk L; Lotz, Jeffery C
Surface Processes of Faceted Growth
NASA Technical Reports Server (NTRS)
Atomic force microscopy and high precision optical interferometry allow to analyze the processes that are in the core of our present understanding of faceted crystal growth. Some of these processes will be reviewed. Recent experiments suggest that the Gibbs-Thomson Law (GTL) may not be applicable to the weakly fluctuating strongly polygonized steps, with low kink density. Propagation rate of a straight short step segment changes with the segment length much steeper than predicted by GTL. If the step fluctuations are still well developed, the typical transition length may be determined just by the radius of rounded comers of the polygonized step. If fluctuations do not have enough time to develop, the kinetic effects may be essential. Indeed, 'communications' between comers of a short straight step segment may occur and, thus, the GTL may be implemented only via kink exchange. E.g., dissolutions of this short segment at macroscopic equilibrium occurs as follows: The kinks are split from one comer as a result of fluctuations, and annihilate with kinks of the opposite sign generated by another comer. Similarly, an exchange via chain of kinks on a rough step is the mechanism to implement the GT Law. If there is a supersaturation with respect to a large crystal, the kinks not only diffuse along the step, but move back the generating comers. This 'wind' prevents communication between the comers and places upper limit supersaturation only below which GTL is applicable. Steps replace kinks in the 3D case, though, of course, another dimensionality brings about another physics. Another specific problem to think about is if fluctuations are always fast enough to provide enough kinks for linear dependence of step rate on supersaturation. Increasing azimuthal polygonization of growth hillocks is a sign of insufficient fluctuation rate. Morphological stability of vicinal faces is usually considered on the basis of mutually parallel steps. Azimuthal anisotropy and interlacing of step bunches inducing the well known bunch splitting is another challenge. Among other challenging problems are: existence of surface diffusion on the crystal/so1ution interface, step interaction in solutions, achievement of step flow modes from liquids, impurity effects. New phenomena essential in biomacromolecular crystallization is another interesting area.
Chernov, A.; Curreri, Peter A. (Technical Monitor)
Supporting multiple paths to objects in information hierarchies: Faceted classification, faceted search, and symbolic links
We present three fundamental, interrelated approaches to support multiple access paths to each terminal object in information hierarchies: faceted classification, faceted search, and web directories with embedded symbolic links. This survey aims to demonstrate how each approach supports users who seek information from multiple perspectives. We achieve this by exploring each approach, the relationships between these approaches, including tradeoffs, and
Saverio Perugini
Facet development for a faceted stretched-membrane dish by Solar Kinetics, Inc
A 3.6-meter diameter stretched-membrane optical facet for a parabolic dish has been successfully designed and demonstrated under contract with Sandia National Laboratories. Twelve facets identical to them will be used to make the lightweight reflector of the dish. The project goal of 2.5-mrad surface accuracy was met with each of the two full-sized prototypes, and accuracies of as low as 1.1 mrad were achieved. The facet weight is 11.7 kg/m{sup 2} (2.4lbs/ft{sup 2}). The facet is similar in construction to the successful stretched-membrane heliostat; it has two thin metal membranes attached to a ring. However, the front membrane for this facet is plastically formed at the factor in order to achieve a shorter facet f/D (approximately 3.0). A passive tether restrains the from membrane when not in operation, that is, when the stabilizing vacuum is off. The optical surface is achieved with a silvered-acrylic film laminated to the metal membrane. The facet is expected to cost $55.40/m{sup 2} at a production rate of 10,000 facets per year and $115, 000/m{sup 2}-at a production rate of 500 facets a year. Several key issues have been resolved. Stress concentrations due to seams in the reflective laminate did not cause membrane rupture during forming as they have for dishes with lower focal length-to-diameter ratios. The laminate survived the forming process and simulated operation without deterioration. The optical effect of the tether on the membrane was tested and found to be very small. Most important, highly accurate shapes were obtained using a simple forming procedure. Additional tests are needed to demonstrate process repeatablility and facet performance in typical operating conditions. 18 refs., 36 figs., 11 tabs.
Schertz, P.T.; Brown, D.C.; Konnerth, A. III (Solar Kinetics, Inc., Dallas, TX (United States)) [Solar Kinetics, Inc., Dallas, TX (United States)
Mirror Facets for the VERITAS Telescopes
NASA Astrophysics Data System (ADS)
Each of the VERITAS telescopes has 345 adjustable glass facets which were manufactured by D.O.T.I., Roundrock, Texas with slumping and grinding to get the optical figure. The facets were aluminized and anodized at the Whipple Observatory. The parameters (reflectivity, focal length and blur circle) were measured. The design specifications for focal length (12.00 m +/- 1%) and spot size (< 10 mm) were surpassed by a factor of two. The anodizing process will be described and the effect of exposure at the VERITAS site on the reflectivity described.
Roache, E.; Irvin, R.; Perkins, J. S.; et al.
Alignment and focus of mirrored facets of a heliosat
Various technologies pertaining to aligning and focusing mirrored facets of a heliostat are described herein. Updating alignment and/or focus of mirrored facets is undertaken through generation of a theoretical image, wherein the theoretical image is indicative of a reflection of the target via the mirrored facets when the mirrored facets are properly aligned. This theoretical image includes reference points that are overlaid on an image of the target as reflected by the mirrored facets of the heliostat. A technician adjusts alignment/focus of a mirrored facet by causing reflected reference markings to become aligned with the reference points in the theoretical image.
Yellowhair, Julius E; Ho, Clifford Kuofei; Diver, Richard B; Moss, Timothy A
Radiofrequency Cannula with Active Tip Radio-opaque Marker: Image Analysis for Facet, Gray Ramus, and Dorsal Root Ganglion Techniques
Background: Radiofrequency neurolysis is a common technique used in the treatment of chronic pain, particularly facet (zygapophyseal joint) arthralgia. A needle-like cannu- la is insulated except for the exposed active tip, which is positioned as parallel and adja- cent as possible to the targeted nerve branch. Via an inserted probe connected to a ra- diofrequency generator, energy flowing from the
Joseph F. Jasper
Multiple facets of macrophages in renal injury
Multiple facets of macrophages in renal injury.Macrophage infiltration is a common feature of renal disease and their presence has been synonymous with tissue damage and progressive renal failure. More recently work has focused on the heterogeneity of macrophage activation and in particular their ability to curtail inflammation and restore normal function. This has led to the view that it is
A hematogenous spread brain abscess invading the right damaged temporomandibular joint.
We report a rare case of a brain abscess which drained spontaneously in a temporomandibular joint damaged by osteoarthritis. The female patient presented to our hospital with a severe headache and pain in the temporomandibular joint. She showed elevated inflammatory parameters with unknown cause. Magnetic resonance imaging of her whole body revealed a large temporal brain abscess extending into the glenoid fossa of the temporomandibular joint. The brain abscess was incised and drained by neurosurgeons in our hospital and in the same operation we resected the articular disc and the affected part of the right temporomandibular joint. Histological examination confirmed a chronic arthrosis in the resected bone of the temporomandibular joint and an inflammatory abscess in the resected brain tissue. The patient recovered well and the inflammation resolved as seen in postoperative investigations. Magnetic resonance imaging a month later confirmed local consolidation in the brain with no sign of residual inflammation. PMID:22440320
Klatt, J; Heiland, M; Gr—be, A; Westphal, M; Schmelzle, R; Pohlenz, P
Facets for Discovery and Exploration in Text Collections
Faceted classifications of text collections provide a useful means of partitioning documents into related groups, however traditional approaches of faceting text collections rely on comprehensive analysis of the subject area or annotated general attributes. In this paper we show the application of basic principles for facet analysis to the development of computational methods for facet classification of text collections. Integration with a visual analytics system is described with summaries of user experiences.
Rose, Stuart J.; Roberts, Ian E.; Cramer, Nicholas O.
Symptomatic sacroiliac joint disease and radiographic evidence of femoroacetabular impingement.
Symptomatic sacroiliac (SI) joint disease is poorly understood. The literature provides no clear aetiology for SI joint pathology, making evaluation and diagnosis challenging. We hypothesised that patients with documented sacroiliac pain might provide insight into the aetiology of these symptoms. Specifically, we questioned whether SI joint symptoms might be associated with abnormal hip radiographs. We reviewed the pelvic and hip radiographs of a prospectively collected cohort of 30 consecutive patients with SI joint pathology. This database included 33 hips from 30 patients. Radiographic analysis included measurements of the lateral centre edge angle, T—nnis angle, and the triangular index, of the ipsilateral hip. Evidence for retrotorsion of the hemipelvis was recorded. Hips were graded on the T—nnis grading system for hip arthrosis. In this cohort 14/33 (42%) of hips had evidence of significant osteoarthrosis indicated by T—nnis grade 2 or greater and 15/33 (45%) displayed subchondral cyst formation around the hip or head neck junction. In assessing acetabular anatomy, 21% (7/33) had retroversion, 12% (4/33) had a lateral centre edge angle >40¯ with 3% (1/33) >45¯. T—nnis angle was <0¯ in 27% (9/33). Coxa profunda and acetabuli protrusio were present in 47% (17/33) and 3% (1/33), respectively. When femoral head morphology was assessed, 33% (11/33) showed evidence of cam impingement. Overall, 76% (25/33) had at least one abnormality on their hip radiograph. A significant number of patients meeting strict diagnostic criteria for SI joint pain had radiographic evidence of femoroacetabular impingement (FAI) and hip arthrosis. The clinician should maintain FAI in the differential diagnosis when investigating patients with buttock pain. PMID:23417531
Morgan, Patrick M; Anderson, Anthony W; Swiontkowski, Marc F
Results from Plasma Wakefield Experiments at FACET
We report initial results of the Plasma Wakefield Acceleration (PWFA) Experiments performed at FACET - Facility for Advanced aCcelertor Experimental Tests at SLAC National Accelerator Laboratory. At FACET a 23 GeV electron beam with 1.8 x 10{sup 10} electrons is compressed to 20 {mu}m longitudinally and focused down to 10 {mu}m x 10 {mu}m transverse spot size for user driven experiments. Construction of the FACET facility completed in May 2011 with a first run of user assisted commissioning throughout the summer. The first PWFA experiments will use single electron bunches combined with a high density lithium plasma to produce accelerating gradients > 10 GeV/m benchmarking the FACET beam and the newly installed experimental hardware. Future plans for further study of plasma wakefield acceleration will be reviewed. The experimental hardware and operation of the plasma heat-pipe oven have been successfully commissioned. Plasma wakefield acceleration was not observed because the electron bunch density was insufficient to ionize the lithium vapor. The remaining commissioning time in summer 2011 will be dedicated to delivering the FACET design parameters for the experimental programs which will begin in early 2012. PWFA experiments require the shorter bunches and smaller transverse sizes to create the plasma and drive large amplitude wakefields. Low emittance and high energy will minimize head erosion which was found to be a limiting factor in acceleration distance and energy gain. We will run the PWFA experiments with the design single bunch conditions in early 2012. Future PWFA experiments at FACET are discussed in [5][6] and include drive and witness bunch production for high energy beam manipulation, ramped bunch to optimize tranformer ratio, field-ionized cesium plasma, preionized plasmas, positron acceleration, etc.. We will install a notch collimator for two-bunch operation as well as new beam diagnostics such as the X-band TCAV [7] to resolve the two bunches. With these new instruments and desired beam parameters in place next year, we will be able to complete the studies of plasma wakefield acceleration in the next few years.
Li, S.Z.; Clarke, C.I.; England, R.J.; Frederico, J.; Gessner, S.J.; Hogan, M.J.; Jobe, R.K.; Litos, M.D.; Walz, D.R.; /SLAC; Muggli, P.; /Munich, Max Planck Inst.; An, W.; Clayton, C.E.; Joshi, C.; Lu, W.; Marsh, K.A.; Mori, W.; Tochitsky, S.; /UCLA; Adli, E.; /U. Oslo
Identifying Facets of Problem Solving in Mathematics Instruction.
ERIC Educational Resources Information Center
Facets of problem solving instruction (PSI) were studied in German mathematics classrooms. Nine different facets of PSI were identified from the research literature, and a video rating form was developed to assess these facets and teacher effectiveness. Videotaped mathematics lessons (n=147) for German eighth graders from the sample for the Third
Klieme, Eckhard; Clausen, Marten
The elephant knee joint: morphological and biomechanical considerations
Elephant limbs display unique morphological features which are related mainly to supporting the enormous body weight of the animal. In elephants, the knee joint plays important roles in weight bearing and locomotion, but anatomical data are sparse and lacking in functional analyses. In addition, the knee joint is affected frequently by arthrosis. Here we examined structures of the knee joint by means of standard anatomical techniques in eight African (Loxodonta africana) and three Asian elephants (Elephas maximus). Furthermore, we performed radiography in five African and two Asian elephants and magnetic resonance imaging (MRI) in one African elephant. Macerated bones of 11 individuals (four African, seven Asian elephants) were measured with a pair of callipers to give standardized measurements of the articular parts. In one Asian and three African elephants, kinematic and functional analyses were carried out using a digitizer and according to the helical axis concept. Some peculiarities of healthy and arthrotic knee joints of elephants were compared with human knees. In contrast to those of other quadruped mammals, the knee joint of elephants displays an extended resting position. The femorotibial joint of elephants shows a high grade of congruency and the menisci are extremely narrow and thin. The four-bar mechanism of the cruciate ligaments exists also in the elephant. The main motion of the knee joint is extensionflexion with a range of motion of 142¯. In elephants, arthrotic alterations of the knee joint can lead to injury or loss of the cranial (anterior) cruciate ligament.
Weissengruber, G E; Fuss, F K; Egger, G; Stanek, G; Hittmair, K M; Forstenpointner, G
Rough surface scattering based on facet model
NASA Technical Reports Server (NTRS)
A model for the radar return from bare ground was developed to calculate the radar cross section of bare ground and the effect of the frequency averaging on the reduction of the variance of the return. It is shown that, by assuming that the distribution of the slope to be Gaussian and that the distribution of the length of the facet to be in the form of the positive side of a Gaussian distribution, the results are in good agreement with experimental data collected by an 8- to 18-GHz radar spectrometer system. It is also shown that information on the exact correlation length of the small structure on the ground is not necessary; an effective correlation length may be calculated based on the facet model and the wavelength of the incident wave.
Khamsi, H. R.; Fung, A. K.; Ulaby, F. T.
Kinetic analysis of anterior cervical discectomy and fusion supplemented with transarticular facet screws.
OBJECT The clinical success rates of anterior cervical discectomy and fusion (ACDF) procedures are substantially reduced as more cervical levels are included in the fusion procedure. One method that has been proposed as an adjunctive technique for multilevel ACDF is the placement of screws across the facet joints ("transfacet screws"). However, the biomechanical stability imparted by transfacet screw placement (either unilaterally or bilaterally) has not been reported. Therefore, the purpose of this study was to determine the acute stability conferred by implementation of unilateral and bilateral transfacet screws to an ACDF construct. METHODS Eight C2-T1 fresh-frozen human cadaveric spines (3 female and 5 male; mean age 50 years) were tested. Three different instrumentation variants were performed on cadaveric cervical spines across C4-7: 1) ACDF with an intervertebral spacer and standard plate/screw instrumentation; 2) ACDF with an intervertebral spacer and standard plate/screw instrumentation with unilateral facet screw placement; and 3) ACDF with an intervertebral spacer and standard plate/screw instrumentation with bilateral facet screw placement. Kinetic ranges of motion in flexion-extension, lateral bending, and axial rotation at 1.5 Nm were captured after each of these procedures and were statistically analyzed for significance. RESULTS All 3 fixation scenarios produced statistically significant reductions (p < 0.05) in all 3 bending planes compared with the intact condition. The addition of a unilateral facet screw to the ACDF construct produced significant reductions at the C4-5 and C6-7 levels in lateral bending and axial rotation but not in flexion-extension motion. Bilateral facet screw fixation did not produce any statistically significant decreases in flexion-extension motion compared with unilateral facet screw fixation. However, in lateral bending, significant reductions at the C4-5 and C5-6 levels were observed with the addition of a second facet screw. The untreated, adjacent levels (C2-3, C3-4, and C7-1) did not demonstrate significant differences in range of motion. CONCLUSIONS The data demonstrated that adjunctive unilateral facet screw fixation to an ACDF construct provides significant gains in stability and should be considered a potential option for increasing the likelihood for obtaining a successful arthrodesis for multilevel ACDF procedures. PMID:24559463
Traynelis, Vincent C; Sherman, Jonathan; Nottmeier, Eric; Singh, Vaneet; McGilvray, Kirk; Puttlitz, Christian M; Leahy, Patrick Devin
Multi-faceted digital pyramid wavefront sensor
NASA Astrophysics Data System (ADS)
The modulated pyramid wavefront sensor is known for its high sensitivity and adjustable dynamic range. The need for mechanically moving parts in a modulated pyramid wavefront sensor can be overcome by using the recently proposed digital pyramid wavefront sensor. In this paper, a digital multi-faceted pyramid wavefront sensor is demonstrated with the use of a reflecting phase-only spatial light modulator. The four-pupil digital pyramid wavefront sensor with 4-facets is extended to 6 and 8-facets. It is noted from the experiments performed under identical low-noise conditions that the performance of the wavefront sensor in terms of the root mean square wavefront error remains nearly the same in cases of four, six and eight pupil configurations. Under the circumstances elucidated here, the results of simulations indicate that in the presence of scatter noise, the pyramid wavefront sensor with greater number of pupils could lead to an improvement over the standard four-pupil pyramid wavefront sensor. Noise from scattering makes the choice of optimal modulation radius critical while sensing in open-loop adaptive optics systems.
Akondi, Vyas; Castillo, Sara; Vohnsen, Brian
Microreflectance inspection of diode laser front facets
NASA Astrophysics Data System (ADS)
We report on specular reflectivity measurements at the position of the waveguide at front facets of commercial diode laser arrays. Since the waveguide thickness is such semiconductor structures amounts about 1 micrometers an even better spatial resolution of the probe light spot is required. For this purpose, a micro-reflectance setup was designed and implemented. For re-locating the optically active region, e.g. after stepped-up operation time, we employ the photosensitivity of the active region by using the photocurrent induced by the probe beam for auto- alignment of the setup. We show for coated InGaAlAs/GaAs- single chip devices that during long-term operation the diode laser front facet reflectivity at the position of an emitter is almost constant with a slight tendency (about 0.002 at 633 nm) to increase. The results are explained in the framework of defect-induced refractive index changes within the semiconductor material close to the interface between waveguide and facet coating.
Doerfel, Fabian; Nerreter, Stefan; Tomm, Jens W.; Grunwald, Ruediger; Kunkel, R.; Luft, Johann
Faceted Magnetron Device Using Discrete Current Sources
NASA Astrophysics Data System (ADS)
A faceted magnetron concept has a cathode structure comprised of field emitters instead of the traditional thermionic cathode. The faceted magnetron structure has been modeled using the 3D particle-in-cell codes VORPAL 5.2 and ICEPIC. The two-dimensional particle trajectory simulation Lorentz2E has been used to model the electron injection from gated field emitters in a slit type structure. The sensitivity of the electron injection into the device was studied using Lorentz2E with the variation in the operating voltages in the cathode structure -as well as the location of the pusher electrode. Volume electron charge was considered in the sensitivity analysis. Surface charge was not included. Together with this work a model of a ten cavity rising sun magnetron was developed using VORPAL 5.2. A cylindrical and pentagonal-shaped cathode was modeled to study the variation of results due to the cathode shape. The results of this model are used to compare with results obtained from ICEPIC. Discrete current sources were also modeled to come from each facet of the pentagon-shaped cathode to study its effect on the magnetron operation. It is planned to generate velocity distributions of the electrons for the VORPAL input by using results generated with Lorentz2E.
Fernandez-Gutierrez, Sulmer; Browning, Jim; Smithe, David; Watrous, Jack
JPL tests of a LaJet concentrator facet
NASA Technical Reports Server (NTRS)
A LaJet Energy Company (LEC) concentrator facet, 60 in. in diameter, was tested for imaging quality. The following two methods were used: (1) autofocus tests with a point source of light at the facet's radius of curvature; and (2) tests with the Sun close to the horizon as a distant source. The tests of the LaJet facet indicate that all of the solar image reflected by an LEC 460 solar concentrator made of like facets should fall within a 9-in. aperture if the outer facets are carefully adjusted. Such a concentrator would have acceptable performance, but complete evaluation must be made with an assembled concentrator.
Dennison, E. W.; Argoud, M. J.
Interventional radiology in bone and joint
Recent radiologic procedures in bone and joints, some of which eliminate the need for surgery are exposed, including: trephine biopsies of the thoracic and lumbar spine, sacro-iliac joints, peripheral bones synovial membrane and soft tissues, using either fluoroscopic echographic or CT guidance - chemonucleolysis - vascular embolization of skeletal tumors and management of vertebral hemangiomas - selective steroid injection in a broad spectrum of diseases including vertebral facet syndrome, cervicobrachial nerve root pain, rotator cuff calcium deposit, bone cysts.
Bard, M.; Laredo, J.D.
Fabrication of faceted nanopores in magnesium
NASA Astrophysics Data System (ADS)
In this paper, using high resolution transmission electron microscopy, we showed the fabrication of faceted nanopores with various shapes in magnesium by focused electron beam (e-beam). The characteristics of nanopore shapes and the crystallographic planes corresponding to the edges of the nanopores were discussed in detail. Interestingly, by manipulating the e-beam (e.g., irradiation direction and duration), the nanopore shape and size could be effectively controlled along different directions. Our results provide important insight into the nanopore patterning in metallic materials and are of fundamental importance concerning the relevant applications, such as nanopore-based sensor, etc.
Wu, Shujing; Cao, Fan; Zheng, He; Sheng, Huaping; Liu, Chun; Liu, Yu; Zhao, Dongshan; Wang, Jianbo
Adaptive mesh refinement for faceted shells
NASA Astrophysics Data System (ADS)
The application of the Zienkiewicz and Zhu error estimator to 3D faceted shells presents some difficulties which arise from the lack of C1 continuity of the geometry. This paper presents a method to circumvent such difficulties based on the existence of a mapping from a flat reference configuration to the actual shell. This mapping is used not only to enable meshes to be generated in a 2D space, but also to define a stress measure (similar to the first Piola-Kirchhoff stress used in large deformation mechanics) which can be consistently smoothed over the reference configuration. A preliminary investigation of the method is provided by three simple examples.
Bonet, J.; Pica, A.; Peiro, J.; Wood, R. D.
An Integrated Facet-Based Library for Arbitrary Software Components
NASA Astrophysics Data System (ADS)
Reuse is an important means of reducing costs and effort during the development of complex software systems. A major challenge is to find suitable components in a large library with reasonable effort. This becomes even harder in today's development practice where a variety of artefacts such as models and documents play an equally important role as source code. Thus, different types of heterogeneous components exist and require consideration in a component search process. One flexible approach to structure (software component) libraries is faceted classification. Faceted classifications and in particular faceted browsing are nowadays widely used in online systems. This paper takes a fresh approach towards using faceted classification in heterogeneous software component libraries by transferring faceted browsing concepts from the web to software component libraries. It presents an architecture and implementation of such a library. This implementation is used to evaluate the applicability of facets in the context of an industry-driven case study.
Schmidt, Matthias; Polowinski, Jan; Johannes, Jendrik; FernÃndez, Miguel A.
Spontaneous Septic Arthritis of the Lumbar Facet Caused by Methicillin-Resistant Staphylococcus aureus in an Otherwise Healthy Adolescent.
We report the case of a 16-year-old boy with isolated septic arthritis of a lumbar facet. This rare presentation of an infection in a lumbar facet joint occurred after minor trauma sustained in a football game. Septic arthritis of the spinal facet joint is an uncommon phenomenon. Only 5 cases have been reported in immunocompromised pediatric patients. To our knowledge, no case of septic arthritis in an immunocompetent pediatric patient has been reported. An otherwise healthy 16-year-old boy presented with 4 weeks of escalating back pain after a minor athletics-related trauma. Evaluation showed incapacitating pain, lumbar musculature spasms, and the absence of fever, hemodynamic, or neurologic changes. Laboratory values were within normal limits. Magnetic resonance images showed a fluid collection within the L3-L4 facet and a localized abscess. Computed tomographic-guided aspiration showed methicillin-resistant Staphylococcus aureus infection, for which the patient received 6 weeks of vancomycin with complete resolution of symptoms. Refractory lumbago in an adolescent requires careful evaluation. PMID:25046186
Papaliodis, Dean N; Roberts, Timothy T; Richardson, Nicholas G; Lawrence, James B
Faceted ceramic fibers, tapes or ribbons and epitaxial devices therefrom
A crystalline article includes a single-crystal ceramic fiber, tape or ribbon. The fiber, tape or ribbon has at least one crystallographic facet along its length, which is generally at least one meter long. In the case of sapphire, the facets are R-plane, M-plane, C-plane or A-plane facets. Epitaxial articles, including superconducting articles, can be formed on the fiber, tape or ribbon.
Goyal, Amit
Faceted ceramic fibers, tapes or ribbons and epitaxial devices therefrom
A crystalline article includes a single-crystal ceramic fiber, tape or ribbon. The fiber, tape or ribbon has at least one crystallographic facet along its length, which is generally at least one meter long. In the case of sapphire, the facets are R-plane, M-plane, C-plane or A-plane facets. Epitaxial articles, including superconducting articles, can be formed on the fiber, tape or ribbon.
Goyal, Amit (Knoxville, TN)
Facet-sparing lumbar decompression with a minimally invasive flexible MicroBlade ShaverÛ versus traditional decompression: quantitative radiographic assessment
Background Laminectomy/laminotomy and foraminotomy are well established surgical techniques for treatment of symptomatic lumbar spinal stenosis. However, these procedures have significant limitations, including limited access to lateral and foraminal compression and postoperative instability. The purpose of this cadaver study was to compare bone, ligament, and soft tissue morphology following lumbar decompression using a minimally invasive MicroBlade ShaverÛ instrument versus hemilaminotomy with foraminotomy (HL). Methods The iO-FlexÛ system utilizes a flexible over-the-wire MicroBlade Shaver instrument designed for facet-sparing, minimally invasive inside-out decompression of the lumbar spine. Unilateral decompression was performed at 36 levels in nine human cadaver specimens, six with age-appropriate degenerative changes and three with radiographically confirmed multilevel stenosis. The iO-Flex system was utilized on alternating sides from L2/3 to L5/S1, and HL was performed on the opposite side at each level by the same investigator. Spinal canal, facet joint, lateral recess, and foraminal morphology were assessed using computed tomography. Results Similar increases in soft tissue canal area and decreases in ligamentum flavum area were noted in nondiseased specimens, although HL required removal of 83% more laminar area (P < 0.01) and 95% more bone resection, including the pars interarticularis and facet joints (P < 0.001), compared with the iO-Flex system. Similar increases in lateral recess diameter were noted in nondiseased specimens using each procedure. In stenotic specimens, the increase in lateral recess diameter was significantly (P = 0.02) greater following use of the iO-Flex system (43%) versus HL (7%). The iO-Flex system resulted in greater facet joint preservation in nondiseased and stenotic specimens. In stenotic specimens, the iO-Flex system resulted in a significantly greater increase in foraminal width compared with HL (24% versus 4%, P = 0.01), with facet joint preservation. Conclusion The iO-Flex system resulted in significantly better decompression of the lateral recess and foraminal areas compared with HL, while preserving posterior spinal elements, including the facet joint.
Lauryssen, Carl; Berven, Sigurd; Mimran, Ronnie; Summa, Christopher; Sheinberg, Michael; Miller, Larry E; Block, Jon E
Psychopathy and instrumental violence: facet level relationships.
The relationship between psychopathy and violence is well established. However, the extent to which psychopathy is related to different types of violent behavior warrants further study. We examined the relationship between instrumental violence, psychopathy, and psychopathic traits among 248 European American and African American adult male county jail inmates. We assessed instrumentality based on subjective motivations for respondent-identified acts of violence. Psychopathy was assessed using the PCL-R based on interview and file review. We controlled for potentially important covariates, namely IQ and prior violence. Results were in part consistent with findings from studies with adolescents, in that we identified a positive relationship between instrumentality of violence and manipulative interpersonal style. Results differed from youth studies with regard to relationships between instrumentality and other facets of psychopathy. The implications of our study are discussed with regard to treatment and the developmental stability of the relationship between psychopathic traits and instrumental violence. PMID:19663661
Walsh, Zach; Swogger, Marc T; Kosson, David S
FACET Tolerances for Static and Dynamic Misalignments
The Facility for AdvancedAccelerator and Experimental Tests (FACET) at the SLAC National Accelerator Laboratory is designed to deliver a beam with a transverse spot size on the order of 10 {micro}m x 10 {micro}m in a new beamline constructed at the two kilometer point of the SLAC linac. Commissioning the beamline requires mitigating alignment errors and their effects, which can be significant and result in spot sizes orders of magnitude larger. Sextupole and quadrupole alignment errors in particular can introduce errors in focusing, steering, and dispersion which can result in spot size growth, beta mismatch, and waist movement. Alignment errors due to static misalignments, mechanical jitter, energy jitter, and other physical processes can be analyzed to determine the level of accuracy and precision that the beamline requires. It is important to recognize these effects and their tolerances in order to deliver a beam as designed.
Federico, Joel
Pulsed radiofrequency application in treatment of chronic zygapophyseal joint pain
BACKGROUND CONTEXT: Chronic zygapophyseal joint arthropathy is a cause of back and neck pain. One proposed method of treating facet joint pathology is ablation of medial branches and dorsal rami with pulsed radiofrequency (RF) waves.PURPOSE: Assessment of efficacy of pulsed RF application for treatment of chronic zygapophyseal joint pain.STUDY DESIGN\\/SETTING: Retrospective study of 114 patients at a pain management clinic.PATIENT
Georgi Mikeladze; Ramon Espinal; Robert Finnegan; James Routon; Dan Martin
Cryoneurolysis for zygapophyseal joint pain: a retrospective analysis of 117 interventions
Purpose Lumbar facet joint syndrome (LFJS) is the cause of pain in 15-54% of the patients with low-back pain. There are few studies\\u000a of cryotherapy for LFJS, focusing mainly on pain scores rather than further outcome measures. The aim of the study was to\\u000a determine the long-term outcome after cryoneurolysis of lumbar facet joints, looking at pain scores, pain-related impairment\\u000a patient
Tilman Wolter; M. Deininger; U. Hubbe; M. Mohadjer; S. Knoeller
The Construct of Agreeableness: Facet vs. Item Level Analysis
ERIC Educational Resources Information Center
The Revised NEO Personality Inventory (NEO PI-R) was developed to operationalize the Five-Factor Model of Personality. Using correlational analysis and confirmatory and exploratory factor analysis, the present study investigates the facet structure of the domain of Agreeableness of the NEO-PI-R at the facet and item level to assess which is a more
Newgent, Rebecca A.; Lee, Sang Min; Higgins, Kristin K.; Mulvenon, Sean W.; Connors, Joanie V.
Search Interface Design Using Faceted Indexing for Web Resources.
ERIC Educational Resources Information Center
Describes an experimental system designed to organize and provide access to Web documents using a faceted pre-coordinate indexing system based on the Deep Structure Indexing System (DSIS) derived from POPSI (Postulate based Permuted Subject Indexing) of Bhattacharyya, and the facet analysis and chain indexing system of Ranganathan. (AEF)
Devadason, Francis; Intaraksa, Neelawat; Patamawongjariya, Pornprapa; Desai, Kavita
Proximal attrition facets: morphometric, demographic, and aging characteristics.
Although interproximal attrition is considered to be limited in modern populations, it has important clinical implications. However, in contrast to occlusal attrition, proximal attrition receives limited scientific attention. The main purpose of the current study was to fill this void. Seven-hundred and sixty-five teeth were collected from 255 skulls of subjects 18-75 yr of age. For each individual, three mandibular teeth (the first and second premolars and the first molar) were examined for proximal attrition facets (PAFs). The results provide detailed information on the size, shape, and location of the facets according to age cohort, gender, and ethnicity. The validity of the method used to measure the facets was also examined. The major findings were as follows: PAFs are usually located on the upper half of the crown proximal aspect; in each tooth, the mesial facet is more lingually positioned and the distal facet is more buccally positioned; the majority of the facets are subrectangular in shape; the size of the facets tends to increase in an anteroposterior direction (from premolars to molars); and facet size and location are age- and sex-dependent and ethnicity-independent. It is our recommendation that dentists bear in mind that interproximal attrition is a dynamic, long-term process and needs to be considered in many clinical scenarios. PMID:24930490
Sarig, Rachel; Hershkovitz, Israel; Shvalb, Nir; Sella-Tunis, Tatiana; May, Hila; Vardimon, Alexander D
Facetedpedia: dynamic generation of query-dependent faceted interfaces for wikipedia
This paper proposes Facetedpedia, a faceted retrieval system for information discovery and exploration in Wikipedia. Given the set of Wikipedia articles resulting from a keyword query, Facetedpedia generates a faceted interface for navigating the result articles. Compared with other faceted retrieval systems, Facetedpedia is fully automatic and dynamic in both facet generation and hierarchy construction, and the facets are based
Chengkai Li; Ning Yan; Senjuti Basu Roy; Lekhendro Lisham; Gautam Das
Role of chemical potential in relaxation of faceted crystal structure
NASA Astrophysics Data System (ADS)
Below the roughening transition, crystal surfaces have macroscopic plateaus, facets, whose evolution is driven by the microscale dynamics of steps. A long-standing puzzle was how to reconcile discrete effects in facet motion with fully continuum approaches. We propose a resolution of this issue via connecting, through a jump condition, the continuum-scale surface chemical potential away from the facet, characterized by variations of the continuum surface free energy, with a chemical potential originating from the decay of atomic steps on top of the facet. The proposed condition accounts for step flow inside a discrete boundary layer near the facet. To validate this approach, we implement in a radial geometry a hybrid discrete-continuum scheme in which the continuum theory is coupled with only a few, minimally three, steps in diffusion-limited kinetics with conical initial data.
Schneider, Joshua P.; Nakamura, Kanna; Margetis, Dionisios
Evolution of triangular topographic facets along active normal faults
NASA Astrophysics Data System (ADS)
Triangular shaped facets, which are generally formed by the erosion of fault - bounded mountain ranges, are arguably one of the most prominent geomorphic features on active normal fault scarps. Some previous studies of triangular facet development have suggested that facet size and slope exhibit a strong linear dependency on fault slip rate, thus linking their growth directly to the kinematics of fault initiation and linkage. Other studies, however, generally conclude that there is no variation in triangular facet geometry (height and slope) with fault slip rate. The landscape of the northeastern Basin and Range Province of the western United States provides an opportunity for addressing this problem. This is due to the presence of well developed triangular facets along active normal faults, as well as spatial variations in fault scale and slip rate. In addition, the Holocene climatic record for this region suggests a dominant tectonic regime, as the faulted landscape shows little evidence of precipitation gradients associated with tectonic uplift. Using GIS-based analyses of USGS 30 m digital elevation data (DEMs) for east - central Idaho and southwestern Montana, we analyze triangular facet geometries along fault systems of varying number of constituent segments. This approach allows us to link these geometries with established patterns of along - strike slip rate variation. For this study, we consider major watersheds to include only catchments with upstream and downstream boundaries extending from the drainage divide to the mapped fault trace, respectively. In order to maintain consistency in the selection criteria for the analyzed triangular facets, only facets bounded on opposite sides by major watersheds were considered. Our preliminary observations reflect a general along - strike increase in the surface area, average slope, and relief of triangular facets from the tips of the fault towards the center. We attribute anomalies in the along - strike geometric measurements of the triangular facets to represent possible locations of fault segment linkage associated with normal fault evolution.
Balogun, A.; Dawers, N. H.; Gasparini, N. M.; Giachetta, E.
Ultra-steep side facets in multi-faceted SiGe/Si(001) Stranski-Krastanow islands
For the prototypical Ge/Si(001) system, we show that at high growth temperature a new type of Stranski-Krastanow islands is formed with side facets steeper than {111} and high aspect ratio. Nano-goniometric analysis of the island shapes reveals the presence of six new facet groups in addition to those previously found for dome or barn-shaped islands. Due to the highly multi-faceted island shape and high aspect ratio, the new island types are named "cupola" islands and their steepest {12 5 3} side facet is inclined by 68¯to the substrate surface. Assessing the relative stability of the new facets from surface area analysis, we find that their stability is similar to that of {113} and {15 3 23} facets of dome islands. The comparison of the different island shapes shows that they form a hierarchical class of geometrical structures, in which the lower aspect ratio islands of barns, domes and pyramids are directly derived from the cupola islands by successive truncation of the pedestal bases without facet rearrangements. The results underline the key role of surface faceting in the process of island formation, which is as crucial for understanding the island's growth evolution as it is important for device applications.
Osteological and Morphometric Observations on Intervertebral Joints in the Canine Pre-diaphragmatic Thoracic Spine (Th1Th9)
The incidence of facet aplasia was investigated in three groups of pure-bred dogs. We examined large breeds (Rough Collies, Doberman Pinschers, Rottweilers, Bernese Mountain Dogs, German Shepherd Dogs), chondrodystrophic breeds (Dachshunds, Pekinese dogs), and small breeds (Yorkshire Terriers, Maltese dogs). Uni- or bilateral aplasia of zygapophyseal (facet) joints was exclusively found in juvenile and adult small dogs, in which the
S. Breit
[Development and biomechanics of the talocrural joint].
We have studied the development of talocrural joint in fetuses, newborns and children. The results of the microscopical, anatomical and biomechanical studies are as follows: 1. The distal extremities of tibia and fibula are joint not only by the distal part of the tibiofibular syndesmosis, but also by an articulation (articulation tibiofibularis distalis). Its articular cavity communicates with the cavity of the talocrural joint and is visible on its arthrographic pictures. This articulation enables the mutual shift and rotation between distal extremities of tibia and fibula-during the plantar flexion fibula turns and shifts round tibia anteriorly, by the dorsal flexion posteriorly. 2. We recommend to preserve the possibility of mutual movements of tibia and fibula in all cases of the surgical treatment of talocrural injuries. 3. Analysis of prostheses of talocrural joint showed why they cannot be functionally successful. They do not respect the physiological movements, the small articulations of tarsus are overloaded. Pain, arthrosis and functional collapse results in these small articulations, because the prostheses change the axis of movements and the biomechanics at all. 4. We have defined conditions for a successful talocrural prosthesis. 5. Study of the topography of the attachment of the Achilles tendon showed, that it develops medially from the axis of the extremity and therefore rotates in the fetus the foot in the equinovarus position. The tendon shifts till the axis during the second half of fetal life. When this shift is temporarily stopped or slown down, the syndrome of pes equinovarus congenitus develops. We recommend the modification of the surgical treatment of pes equinovarus congenitus: transposition of the Achilles tendon in the axial position. PMID:8718792
Doskocil, M
Facet degradation of high-power diode laser arrays
NASA Astrophysics Data System (ADS)
Micro-Raman facet temperatures of high-power diode lasers with different waveguide architectures are compared. For regular operation conditions, the thermal behavior of `unaged' arrays emitting in the 808-nm wavelength region with different architectures is similar, however, with an increased load thermal behaviors differ significantly and exhibit failure events at facet temperatures typically between 150 and 450 ¯C. From various experiments, among them facet temperature measurements for ultrahigh-power operation as well as by preparative failure analytics, we provide evidence that in arrays the front facets are significantly affected by device operation and influence the failure behavior of the whole high-power diode laser also in cases when the device failure is accompanied by dislocation creation inside the device.
Tomm, J. W.; Thamm, E.; Bðrwolff, A.; Elsaesser, T.; Luft, J.; Baeumler, M.; Mueller, S.; Jantz, W.; Rechenberg, I.; Erbert, G.
Titanium dioxide nanoswords with highly reactive, photocatalytic facets
Titanium dioxide (TiO2) is one of the most widely studied and important materials for catalysis, photovoltaics, and surface science applications, but the ability to consistently control the relative exposure of higher surface energy facets during synthesis remains challenging. Here, we present the repeatable synthesis of highly reactive, rutile {001} or {101} facets on broad, sword-shaped TiO2 nanostructures rapidly synthesized in
Brian D Sosnowchik; Heather C Chiamori; Yong Ding; Jong-Yoon Ha; Zhong Lin Wang; Liwei Lin
GaAs laser reliability and protective facet coatings
We have investigated the effects of Al2O3 facet coatings on the reliability of GaAs- (Al,Ga)As double-heterostructure stripe-geometry (12 ?) lasers operated cw in a 70 ¯C dry-nitrogen ambient with power outputs equal to 5Ý2 mW\\/facet. No improvement was seen in the median lifetime of coated devices (some of which also had their sidewalls etched to remove saw-cut damaged material) in
F. R. Nash; R. L. Hartman; N. M. Denkin; R. W. Dixon
Knee joint transplantation combined with surgical angiogenesis in rabbits - a new experimental model
Summary Purpose We have previously described a means to maintain bone allotransplant viability, without long-term immune modulation, replacing allogenic bone vasculature with autogenous vessels. A rabbit model for whole knee joint transplantation was developed and tested using the same methodology, initially as an autotransplant. Materials/Methods Eight New Zealand White rabbit knee joints were elevated on a popliteal vessel pedicle to evaluate limb viability in a non-survival study. Ten additional joints were elevated and replaced orthotopically in a fashion identical to allotransplantation, obviating only microsurgical repairs and immunosuppression. A superficial inferior epigastric facial (SIEF) flap and a saphenous arteriovenous (AV) bundle were introduced into the femur and tibia respectively, generating a neoangiogenic bone circulation. In allogenic transplantation, this step maintains viability after cessation of immunosuppression. Sixteen weeks later, x-rays, microangiography, histology, histomorphometry and biomechanical analysis were performed. Results Limb viability was preserved in the initial 8 animals. Both soft tissue and bone healing occurred in 10 orthotopic transplants. Surgical angiogenesis from the SIEF flap and AV bundle was always present. Bone and joint viability was maintained, with demonstrable new bone formation. Bone strength was less than the opposite side. Arthrosis and joint contractures were frequent. Conclusion We have developed a rabbit knee joint model and evaluation methods suitable for subsequent studies of whole joint allotransplantation.
Kremer, Thomas; Giusti, Guilherme; Friedrich, Patricia F.; Willems, Wouter; Bishop, Allen T.; Giessler, Goetz A.
High-Index Facets in Gold Nanocrystals Elucidated by Coherent Electron Diffraction
Characterization of high index facets in noble metal nanocrystals for plasmonics and catalysis has been a challenge due to their small sizes and complex shapes. Here, we present an approach to determine the high index facets of nanocrystals using streaked Bragg reflections in coherent electron diffraction patterns, and provide a comparison of high index facets on unusual nanostructures such as trisoctahedra. We report new high index facets in trisoctahedra and previous unappreciated diversity in facet sharpness.
Shah, Amish B.; Sivapalan, Sean T.; DeVetter, Brent M.; Yang, Timothy K.; Wen, Jianguo; Bhargava, Rohit; Murphy, Catherine J.; Zuo, Jian-Min
Investigating facets of personality in adult pathological gamblers with ADHD
SUMMARY The present study explored facets of personality in a sample of pathological gamblers with ADHD (n = 52) and without ADHD (n = 43). Participants were assessed for psychopathology and gambling disorders using the Mini International Neuropsychiatric Interview, the National Opinion Research Center DSM Screen for Gambling Problems, and the Adult ADHD Self-Report Scale. Facets of personality were assessed using the NEO Personality InventoryRevised. Group differences emerged across several facets of personality when analyzed using multivariate statistics. Although both groups experienced difficulties in several areas compared with norming data (e.g., greater depression, higher impulsivity, lower self-esteem and lower self-discipline), these facets of personality were more pronounced in pathological gamblers with ADHD. Most notable among these differences are tendencies for gamblers with ADHD to experience greater levels of emotional instability, interpersonal sensitivity and stress proneness. Pathological gamblers with ADHD also appear to experience lower self-esteem, greater difficulty being assertive and lower levels of self-discipline. Surprisingly, both groups were comparable on facets of impulsivity. These findings suggest that pathological gamblers diagnosed with adult ADHD may experience additional challenges compared with pathological gamblers without ADHD.
Davtian, Margarit; Reid, Rory C; Fong, Timothy W
Titanium dioxide nanoswords with highly reactive, photocatalytic facets.
Titanium dioxide (TiO(2)) is one of the most widely studied and important materials for catalysis, photovoltaics, and surface science applications, but the ability to consistently control the relative exposure of higher surface energy facets during synthesis remains challenging. Here, we present the repeatable synthesis of highly reactive, rutile {001} or {101} facets on broad, sword-shaped TiO(2) nanostructures rapidly synthesized in minutes. Growth occurs along planes of lower surface energy, repeatedly yielding nanostructures with large, high energy facets. The quantitative photocatalytic reactivity of the nanoswords, demonstrated by the photoreduction of silver, is over an order of magnitude higher than reference low energy TiO(2){110} substrates. Therefore, the higher surface energy dominated TiO(2) nanoswords are ideal structures for characterizing the physicochemical properties of rutile TiO(2), and may be used to enhance a variety of catalytic, optical, and clean-technology applications. PMID:21060143
Sosnowchik, Brian D; Chiamori, Heather C; Ding, Yong; Ha, Jong-Yoon; Wang, Zhong Lin; Lin, Liwei
New surfaces stabilized by adsorbate-induced faceting
NASA Astrophysics Data System (ADS)
Faceting is a form of self-assembly of single-crystal surfaces at the nanometer-scale in which an initially planar surface converts to a hill-and-valley structure, exposing new faces of low-index surfaces. Our recent studies revealed that, upon annealing in O2, three-sided nanoscale pyramids form on Ir(210) exposing smooth {311} and partially restructured (110) faces. Through a combination of scanning tunneling microscopy and density functional theory, we identify this structure to be a stepped double-missing-row reconstruction, which is only stable on nanopyramidal facets, not on a planar Ir(110) surface. This faceting-enabled stabilization of a hitherto unstable surface points to a new approach to prepare nanoscale model catalysts for structure-sensitivity studies in heterogeneous (electro-)catalysis with high selectivity and reactivity.
Kaghazchi, Payam; Jacob, Timo; Ermanoski, Ivan; Chen, Wenhua; Madey, Theodore E.
Faceted spurs at normal fault scarps: Insights from numerical modeling
NASA Astrophysics Data System (ADS)
We present a combined surface processes and tectonic model which allows us to determine the climatic and tectonic parameters that control the development of faceted spurs at normal fault scarps. Sensitivity tests to climatic parameter values are performed. For a given precipitation rate, when hillslope diffusion is high and channel bedrock is highly resistant to erosion, the scarp is smooth and undissected. When, instead, the bedrock is easily eroded and diffusion is limited, numerous channels develop and the scarp becomes deeply incised. Between these two end-member states, diffusion and incision compete to produce a range of scarp morphologies, including faceted spurs. The sensitivity tests allow us to determine a dimensionless ratio of erosion, f, for which faceted spurs can develop. This study evidences a strong dependence of facet slope angle on throw rate for throw rates between 0.4 and 0.7 mm/a. Facet height is also shown to be a linear function of fault throw rate. Model performance is tested on the Wasatch Fault, Utah, using topographic, geologic, and seismologic data. A Monte Carlo inversion on the topography of a portion of the Weber segment shows that the 5 Ma long development of this scarp has been dominated by a low effective precipitation rate (1.1 m/a) and a moderate diffusion coefficient (0.13 m2/a). Results demonstrate the ability of our model to estimate normal fault throw rates from the height of triangular facets and to retrieve the average long-term diffusion and incision parameters that prevailed during scarp evolution using an accurate 2-D misfit criterion.
Petit, C.; Gunnell, Y.; Gonga-Saholiariliva, N.; Meyer, B.; SÕGuinot, J.
Mapping Mindfulness Facets onto Dimensions of Anxiety and Depression
Background Mindfulness has been associated with anxiety and depression, but the ways in which specific facets of mindfulness relate to symptoms of anxiety and depression remains unclear. The purpose of the current study was to investigate associations between specific facets of mindfulness (e.g., observing, describing, nonjudging, acting with awareness, and nonreactivity) and dimensions of anxiety and depression symptoms (e.g., anxious arousal, general distress-anxiety, general distress-depression, and anhedonic depression) while controlling for shared variance among variables. Methods Participants were 187 treatment-seeking adults. Mindfulness was measured using the Five Facet Mindfulness Questionnaire and symptoms of depression and anxiety were measured using the Mood and Anxiety Symptom Questionnaire. Results Bivariate correlations showed that all facets of mindfulness were significantly related to all dimensions of anxiety and depression with two exceptions: describing was unrelated to general distress -anxiety, and observing was unrelated to all symptom clusters. Path analysis was used to simultaneously examine associations between mindfulness facets and depression and anxiety symptoms. Significant and marginally significant pathways were retained to construct a more parsimonious model and model fit indices were examined. The parsimonious model indicated that nonreactivity was significantly inversely associated with general distress anxiety symptoms. Describing was significantly inversely associated with anxious arousal, while observing was significantly positively associated with it. Nonjudging and nonreactivity were significantly inversely related to general distress-depression and anhedonic depression symptomatology. Acting with awareness was not significantly associated with any dimensions of anxiety or depression. Conclusions Findings support associations between specific facets of mindfulness and dimensions of anxiety and depression and highlight the potential utility of targeting these specific aspects of mindfulness in interventions for anxiety and mood disorders.
Desrosiers, Alethea; Klemanski, David H.; Nolen-Hoeksema, Susan
The patellar syndrome-a complication secondary to endoprosthetic replacement of the knee joint: a retrospective study of 102 knee joints over a period of seven years.
Until recently, loosening, infection and fractures of the prosthesis have been considered the only major complications of otherwise good initial results with total endoprosthetic replacement of the knee joint; however, another serious long term complication has become apparent. Severe degenerative changes of the retropatellar cartilage are being observed, which seem to be caused by a possible axial malalignment of the knee, progression of a preexisting retropatellar arthrosis, and additional metallosis induced by the prosthesis. The resulting symptoms and complaints, in accordance with Debeyre, are summarized by the term Patellar Syndrome. Our studies indicate that these symptoms develop in 50% of all patients with a total knee endoprosthesis within three years after surgery. In 10% of the cases these symptoms are severe enough to require additional surgical intervention. PMID:24823189
Kohler, G; Richter, R; Coldewey, J F
Reduction of fiber facet reflection by a curved core termination
NASA Astrophysics Data System (ADS)
A method to reduce end facet reflectivity of optical fibers by curving the fiber core is presented. The curved end core is obtained by first angle cleaving the fiber end and then balling up the fiber tip by a fusion process. The light escapes from the fiber core at the curve and follows his path through the cladding material up to the balled up fiber surface. Thus, the fiber termination acts as a beam expander and at the same time the facet reflectivity is reduced by >38 dB.
MartÚnez-Rios, A.; Torres-Gµmez, I.; Mata-ChÃvez, R. I.; Selvas-Aguilar, R.
Nonlinear Wavelength Selection in Surface Faceting under Electromigration
NASA Astrophysics Data System (ADS)
We report on the control of the faceting of crystal surfaces by means of surface electromigration. When electromigration reinforces the faceting instability, we find perpetual coarsening with a wavelength increasing as t1/2. For strongly stabilizing electromigration, the surface is stable. For weakly stabilizing electromigration, a cellular pattern is obtained, with a nonlinearly selected wavelength. The selection mechanism is not caused by an instability of steady states, as suggested by previous works in the literature. Instead, the dynamics is found to exhibit coarsening before reaching a continuous family of stable nonequilibrium steady states.
Barakat, Fatima; Martens, Kirsten; Pierre-Louis, Olivier
Generalizability Theory and Many-Facet Rasch Measurement.
ERIC Educational Resources Information Center
Generalizability theory (G-theory) and many-facet Rasch measurement (Rasch) manage the variability inherent when raters rate examinees on test items. The purpose of G-theory is to estimate test reliability in a raw score metric. Unadjusted examinee raw scores are reported as measures. A variance component is estimated for the examinee
Linacre, John M.
A Fully Faceted Syntax for Library of Congress Subject Headings
Moving to a fully faceted syntax would resolve three problems facing Library of Congress Subject Headings (LCSH): (1) Inconsistent syntax rules; (2) Inability to create headings that are coextensive with the topic of a work; and (3) Lack of effective displays for long lists of subdivisions under a single subject heading in OPACs and similar electronic displays. The authors advocate
James D. Anderson; Melissa A. Hofmann
Librarianship; A Faceted Classification Scheme as a Teaching Aid.
National Technical Information Service (NTIS)
Presented is a guide to the faceted classification scheme of the library collection at the Institute of Librarianship of the University of Ibadan. The collection covers librarianship in many countries as well as a number of marginal subjects, and is accum...
M. A. Greaves
Librarianship; A Faceted Classification Scheme as a Teaching Aid.
ERIC Educational Resources Information Center
Presented is a guide to the faceted classification scheme of the library collection at the Institute of Librarianship of the University of Ibadan. The collection covers librarianship in many countries as well as a number of marginal subjects, and is accumulated with specific regard to the Institute's courses. The scheme is small, and in its
Greaves, Monica A.
Exploring Facets of Personality and Escapism in Pathological Gamblers
This study explored facets of personality between pathological gamblers (n = 69) and nonpathological gamblers (n = 55) in a convenience sample in Los Angeles, California. Pathological gamblers were more prone to mood disturbance, impulsivity, feelings of frustration, interpersonal sensitivity, vulnerability to distress, and distrust of others as measured by the NEO Personality InventoryRevised. Pathological gamblers also reported diminished competence
Rory C. Reid; Desiree S. Li; Jean Lopez; Michael Collard; Iman Parhami; Reef Karim; Timothy Fong
Growth of Faceted Crystals in a Snow Cover.
National Technical Information Service (NTIS)
Ice grains in a snow cover with a low temperature gradient assume a well-rounded equilibrium form. However, at temperature gradients of 0.1 to 0.2 C/cm (depending somewhat on temperature and snow density), the rounded grains recrystallize into a faceted k...
S. C. Colbeck
Planar Concave Grating Demultiplexer with Distributed Bragg Reflection Facets
We present measurement results of a 4-channel silicon-on-insulator grating demultiplexer fabricated in a CMOS-line. On-chip loss is reduced below 4.5dB over a broad wavelength range by replacing each facet by a second order Bragg reflector.
T. Brouckaert; Wim Bogaerts; Pieter Dumon; Shankar Kumar Selvaraja; Gunther Roelkens; Dries Van Thourhout; Roel Baets
BIT at TREC 2009 Faceted Blog Distillation Task.
National Technical Information Service (NTIS)
This Paper presents the work done for the TREC 2009 faceted blog distillation task of blog track. In our approach, we use a mixture of language models based on global representation. Our model can be regarded as a combination of topic relevance model and ...
C. Zhang P. Jiang Q. Yang Z. Niu
Depression in the work of British health visitors: Clinical facets
The primary health care setting has been established as a key venue for identifying and working with depression. Despite this, and the high risk of depression experienced by women in the post-natal period, maternal depression has been little examined in the work of health visitors. This study focuses on clinical facets of this work, including the rate and content of
Michael Sheppard
The Cool and Belkin Faceted Classification of Information Interactions Revisited
ERIC Educational Resources Information Center
Introduction: The complexity of human information activity is a challenge for both practice and research in information sciences and information management. Literature presents a wealth of approaches to analytically structure and make sense of human information activity including a faceted classification model of information interactions published
Huvila, Isto
Beyond Conflict: Functional Facets of the Work-Family Interplay
ERIC Educational Resources Information Center
The present paper deals with three positive facets of the work-family interplay, i.e., transfer of competencies, transfer of positive mood, and cross-domain compensation. The latter refers to the experience that engagement in one domain helps dealing with failures in the other domain. In two correlational studies (N[subscript 1] = 107 working
Wiese, Bettina S.; Seiger, Christine P.; Schmid, Christian M.; Freund, Alexandra M.
Aerosol synthesis and reactive behavior of faceted aluminum nanocrystals
We show a low temperature gas-phase synthesis route to produce faceted aluminum crystals in the aerosol phase. Use of triisobutylaluminum whose decomposition temperature is below the melting point of elemental aluminum enabled us to grow nanocrystals from its vapor. TEM shows both polyhedral crystalline and spherical particle morphologies, but with the addition of an annealing furnace one can significantly enhance
Dan A. Kaplowitz; R. J. Jouet; Michael R. Zachariah
Calculation of farfield distortion for a tilted-facet SOA
Semiconductor optical amplifiers (SOAs) are very important elements for telecommunications, computer communications, and signal processing applications. For stable, low noise operation, the modal reflection into the guided SOA mode must be minimized; modal reflectivity typically has to be kept below about {minus}40 dB. This can be accomplished by antireflection (AR) coatings, or by tilting of the SOA end facet. The latter approach has been vigorously pursued recently, because effective AR coatings require very high tolerances and have polarization-dependent reflectivities. Consequently, there has been a great deal of theoretical effort aimed at calculating the modal reflectivity from tilted interfaces, using a variety of approaches. However, there has been little attention directed toward calculating the transmitted field of a tilted-facet SOA. This is a problem of considerable importance, because the coupling of the SOA light to an element such as an optical fiber depends critically on the field distribution at the entrance plane to the fiber. Moreover, experimental measurements of the farfield of tilted-facet SOAs have revealed a curious crescent-shaped intensity distribution. To improve coupling efficiency it is important to understand to what extent this phenomenon is due to the SOA modal field distribution and to what extent it is due to the tilted interface. The authors explain the crescent-shaped farfield intensity distribution of tilted-facet SOAs using vector wave optics, and discuss implications for coupling to other optical elements.
Ratowsky, R.P.; Dijaili, S.; Walker, J.; Patterson, F.; Kallman, J.; Deri, R.
Unilateral axis facet hypertrophy--a rare case of irreducible rotatory atlantoaxial dislocation and a review of the literature.
Fixed atlantoaxial dislocations are difficult to treat and there is no consensus in the treatment protocol. Unilateral enlargement of the atlas-axis facet complex in fixed atlantoaxial dislocations is a very rare condition. These pathologies are usually quite unstable and surgical treatment is necessary in unreductable cases. A 52-year-old woman with a diagnosis of irreducible-fixed rotatory atlantoaxial dislocation presented with acute onset of dizziness, loss of balance, and tetraparesis. She was under 8 years of conservative follow-up. Review of radiology revealed unilateral C2 superior facet hypertrophy compressing the medulla and obstructing the vertebral artery. To treat this condition, we have used a posterior midline approach and removed the lateral portions of the posterior rim of the foramen magnum and the assimilated posterior arch of C1. The V3 segments of the vertebral arteries were exposed bilaterally. The atlantoaxial joint complex on the left was hypertrophied compressing V3. We have removed hypertrophied lateral mass of the atlas and the hypertrophic superior articular facet of C2 for decompression. Patency of both vertebral arteries were checked intraoperatively by Doppler and indocyanine green angiography. We have fixated craniocervical junction on the same session. Patient was neurologically intact and she had confirmed fusion on the surgical site after three years of follow-up. This is a rare case of unilateral hypertrophy of the C2 superior articular facet in a fixed atlantoaxial rotatory dislocation. Progressive compression of medulla and the left vertebral artery leaded to clinical worsening of neurology in this case after 8 years of follow-up. Surgical treatment was necessary for neurological decompression and to establish stability. PMID:23903713
Atalay, Basar; T■re, Ugur
Terahertz Light Source and User Area at FACET
FACET at SLAC provides high charge, high peak current, low emittance electron beam that is bunched at THz wavelength scale during its normal operation. A THz light source based coherent transition radiation (CTR) from this beam would potentially be the brightest short-pulse THz source ever constructed. Efforts have been put into building this photon source together with a user area, to provide a platform to utilize this unique THz radiation for novel nonlinear and ultrafast phenomena researches and experiments. Being a long-time underutilized portion of the electromagnetic spectrum, terahertz (100 GHz {approx} 10 THz) spectral range is experiencing a renaissance in recent years, with broad interests from chemical and biological imaging, material science, telecommunication, semiconductor and superconductor research, etc. Nevertheless, the paucity of THz sources especially strong THz radiation hinders both its commercial applications and nonlinear processes research. FACET - Facilities for Accelerator science and Experimental Test beams at SLAC - provides 23 GeV electron beam with peak currents of {approx} 20 kA that can be focused down to 100 {mu}m{sup 2} transversely. Such an intense electron beam, when compressed to sub-picosecond longitudinal bunch length, coherently radiates high intensity EM fields well within THz frequency range that are orders of magnitude stronger than those available from laboratory tabletop THz sources, which will enable a wide variety of THz related research opportunities. Together with a description of the FACET beamline and electron beam parameters, this paper will report FACET THz radiation generation via coherent transition radiation and calculated photon yield and power spectrum. A user table is being set up along the THz radiation extraction sites, and equipped with various signal diagnostics including THz power detector, Michelson interferometer, sample stages, and sets of motorized optical components. This setup will also be presented. Potential THz research areas including studies of magnetism, ferroelectric switching dynamics, semiconductor devices and chemical reaction controls have already been proposed for the FACET THz area.
Wu, Z.; Li, S.Z.; Litos, M.; Fisher, A.D.; Hogan, M.J.; /SLAC
Surgical treatment of Rockwood grade-V acromioclavicular joint dislocations
Background and purpose Long-term outcome after surgery for grade-V acromioclavicular joint dislocation has not been reported. We performed a retrospective analysis of functional and radiographic outcome 1522 years after surgery. Patients and methods We examined 50 patients who were treated at our hospital between April 1985 and December 1993. Various methods of stabilization were used: K-wires (n = 36), 4.5-mm screw (n = 12), or biodegradable screw (n = 2). Osteosynthesis material was removed after 68 weeks. Mean follow-up time was 18 (1522) years. Outcomes were assessed with the Constant shoulder (CS) score, Disabilities of the Arm, Shoulder, and Hand (DASH) score, the simple shoulder test (SST), the Copeland shoulder impingement test, the cross-arm test, pain, stability of the AC joint, and complications. From radiographs, we evaluated AC and glenohumeral (GH) arthrosis, osteolysis of the lateral clavicle, and alignment of the clavicle with the acromion. Results Mean values were 90 (75100) in CS score, 5.1 (041) in DASH score, and 11 (212) in SST. There was no statistically significant difference in CS score between the injured shoulder and the uninjured shoulder. The AC joint was clinically stable in 42 patients. In 38 patients, the clavicle alignment with the acromion was normal in radiographs. Lateral clavicle osteolysis (10 patients) appeared to be associated with permanent AC joint dislocation. Interpretation Surgery with a temporary fixation for acute grade-V AC joint dislocation leads to successful long-term functional results. Only minor disability occurred in some patients.
Low-threshold InGaAsP laser with etched facets by inductively coupled plasma
NASA Astrophysics Data System (ADS)
Low threshold semiconductor lasers with etched facets have been fabricated by inductively coupled plasma (ICP) dry etching technology. To ensure vertical and smooth etched facets, a novel Cl2/CH4/Ar mixture has been adopted for the ICP etching process. The typical threshold current of etched-facet lasers is about 18 mA, which is as low as that of lasers with cleaved facets and similar cavity length.
Wang, Jian; Xiong, Bing; Sun, Changzheng; Hao, Zhi-Biao; Luo, Yi
... ankles and toes. Other types of arthritis include gout or pseudogout. Sometimes, there is a mechanical problem ... for more information on osteoarthritis, rheumatoid arthritis and gout. How Common are Joint Problems? Osteoarthritis, which affects ...
A selective etching phenomenon on {001} faceted anatase titanium dioxide single crystal surfaces by hydrofluoric acid.
A selective etching phenomenon on {001} faceted anatase TiO(2) single crystal surfaces by HF and associated etching mechanism are reported. Density functional theory (DFT) calculations reveal that HF stabilizes the grown {001} facets at low concentrations, but selectively destroys the grown {001} facets at high concentrations. PMID:21240390
Wang, Yun; Zhang, Haimin; Han, Yanhe; Liu, Porun; Yao, Xiangdong; Zhao, Huijun
Growth mechanism of twin-related and twin-free facet Si dendrites
The various types of facet Si dendrites observed on splat-quenched surfaces were analyzed in order to understand why the growth direction and morphology of the facet Si dendrites change with increasing undercooling. The growth directions of typical facet dendrites were determined to be ?211?, ?110? and ?100? using an electron backscatter pattern apparatus. It was found that both the ?211?
K. Nagashio; K. Kuribayashi
Observation of natural oxide growth on silicon facets using an atomic force microscope with current measurement
Natural oxide growth on silicon facets is observed through an atomic force microscope (AFM) with current measurement. The sample is prepared by means of cleaning and heating a silicon (111) surface with direct electric heating in an ultrahigh vacuum, which creates various facets formed by step bunching. The silicon facets and steps can be observed with the AFM in air.
Sumio Hosaka; Hajime Koyanagi; Tsuyoshi Hasegawa; Shigeyuki Hosoki; Atsushi Hiraiwa
Multibeam Altimeter Navigation Update Using Faceted Shape Model
NASA Technical Reports Server (NTRS)
A method of incorporating information, acquired by a multibeam laser or radar altimeter system, pertaining to the distance and direction between the system and a nearby target body, into an estimate of the state of a vehicle upon which the system is mounted, involves the use of a faceted model to represent the shape of the target body. Fundamentally, what one seeks to measure is the distance from the vehicle to the target body.
Bayard, David S.; Brugarolas, Paul; Broschart, Steve
Framework Application for Core Edge Transport Simulation (FACETS)
The FACETS (Framework Application for Core-Edge Transport Simulations) project of Scientific Discovery through Advanced Computing (SciDAC) Program was aimed at providing a high-fidelity whole-tokamak modeling for the U.S. magnetic fusion energy program and ITER through coupling separate components for each of the core region, edge region, and wall, with realistic plasma particles and power sources and turbulent transport simulation. The project also aimed at developing advanced numerical algorithms, efficient implicit coupling methods, and software tools utilizing the leadership class computing facilities under Advanced Scientific Computing Research (ASCR). The FACETS project was conducted by a multi-discipline, multi-institutional teams, the Lead PI was J.R. Cary (Tech-X Corp.). In the FACETS project, the Applied Plasma Theory Group at the MAE Department of UCSD developed the Wall and Plasma-Surface Interaction (WALLPSI) module, performed its validation against experimental data, and integrated it into the developed framework. WALLPSI is a one-dimensional, coarse grained, reaction/advection/diffusion code applied to each material boundary cell in the common modeling domain for a tokamak. It incorporates an advanced model for plasma particle transport and retention in the solid matter of plasma facing components, simulation of plasma heat power load handling, calculation of erosion/deposition, and simulation of synergistic effects in strong plasma-wall coupling.
Krasheninnikov, Sergei; Pigarov, Alexander
Emitter failure and thermal facet load in high-power laser diode arrays
NASA Astrophysics Data System (ADS)
We report on micro-Raman facet temperature measurements carried out in asymmetrically coated high-power laser diode arrays. Facet temperatures of up to 600 ¯C are reproducibly found for high-power operation. The data are modeled using an approach based on the finite element method. Thus we are able to infer the power management of the device from the facet temperature data. Up to 7% of the total heat power is concentrated at the front facet. Furthermore, we determine the thermal load at the front facet versus the operation current, which is a key parameter for modeling high-power devices.
Puchert, R.; Tomm, J. W.; Jaeger, A.; Bðrwolff, A.; Luft, J.; Spðth, W.
Characteristics of facets in Si-doped GaAs crystals grown by horizontal Bridgman technique
NASA Astrophysics Data System (ADS)
Dislocation free Si-doped GaAs crystals, 2 inches in diameter, 30 cm in length and carrier concentration of 10 18 cm -3, have been growm by horizontal Bridgman (HB) technique. Large facets were found to be more prone to form under a longitudinal temperature gradient less than 1¯C/cm. Characteristics of facets in these HB grown GaAs crystals have been investigated. The occurence of large facets resulted in the lifting of the top surface of the crystal. Facets were found to be more prone to form by reducing the temperature gradient, increasing the Si-dopant concentration and the growth rate. Perpendicular twins, which were related to the (1₤, 1₤, 1₤) facet growth, were generated at the positions where the facet size varied drastically. These twins were identified to be 60¯ rotation twins by chemical etching method. The carrier concentration of the facet area, as measured by Van der Pauw and spreading resistance methods, was found to be 1.7-2.0 times higher than that of the non-facet area. The dislocations in the non-facet area were observed to terminate at the boundary of facet and non-facet areas.
Chen, T. P.; Guo, Y. D.; Huang, T. S.; Chen, L. J.
Subtalar joint stress imaging with tomosynthesis.
The purpose of this study was to perform stress imaging of hindfoot inversion and eversion using tomosynthesis and to assess the subtalar joint range of motion (ROM) of healthy subjects. The subjects were 15 healthy volunteers with a mean age of 29.1 years. Coronal tomosynthesis stress imaging of the subtalar joint was performed in a total of 30 left and right ankles. A Telos stress device was used for the stress load, and the load was 150 N for both inversion and eversion. Tomographic images in which the posterior talocalcaneal joint could be confirmed on the neutral position images were used in measurements. The angle of the intersection formed by a line through the lateral articular facet of the posterior talocalcaneal joint and a line through the surface of the trochlea of the talus was measured. The mean change in the angle of the calcaneus with respect to the talus was 10.3 Ý 4.8¯ with inversion stress and 5.0 Ý 3.8¯ with eversion stress from the neutral position. The result was a clearer depiction of the subtalar joint, and inversion and eversion ROM of the subtalar joint was shown to be about 15¯ in healthy subjects. Levels of Evidence: Diagnostic, Level IV. PMID:24686905
Teramoto, Atsushi; Watanabe, Kota; Takashima, Hiroyuki; Yamashita, Toshihiko
Lead-Free Solder Joint Reliability
Lead-free solder joint reliability is a multi-faceted and challenging topic. Lead-free solders such as eutectic SnAg and SnBi\\u000a have been used successfully in niche applications for many years. With the advent of no-lead (Pb) legislation, a multitude\\u000a of soldering alloys has been proposed for mainstream electronic applications. The high number of lead-free alloy options remains\\u000a a major factor slowing the
Jean-Paul Clech
The instant axis of rotation influences facet forces at L5\\/S1 during flexion\\/extension and lateral bending
Because the disc and facets work together to constrain spinal kinematics, changes in the instant axis of rotation associated with disc degeneration or disc replacement may adversely influence risk for facet overloading and arthritis. The relationships between L5\\/S1 segmental kinematics and facet forces are not well defined, since previous studies have separated investigations of spinal motion and facet force. The
Marc-Antoine Rousseau; David S. Bradford; Tamer M. Hadi; Kirk L. Pedersen; Jeffery C. Lotz
Sub-Facet Heterogeneity of the Urban Surface Energy Budget
NASA Astrophysics Data System (ADS)
The Princeton Urban Canopy Model (PUCM) and observational data are combined to understand the influence of urban sub-facet heterogeneity, and the associated influence of material properties, on the urban surface energy budget. This heterogeneity is related to the different surfaces and materials (asphalt, concrete, grass, black roofs, green roofs, etc.) that are typically found within one urban facet (roof, wall, and ground). Of particular interest is the role of water storage and evaporation from urban surfaces in modulating the energy budget. The PUCM is evaluated at sites of various urban densities. Subsequently, one densely-built site is selected for in-depth analysis and the model is applied, with sub-facet resolution, to simulate the water and energy budgets. Our analyses show that while all built surfaces convert most of the incoming energy into sensible rather than latent heat, sensible heat fluxes from asphalt and non-reflective rooftops are twice as high as those from concrete surfaces and light colored roofs. Another important and commonly observed characteristic of urban areas- the shift in peak time of sensible heat compared to rural areas, is shown to be mainly linked to concrete's high heat storage capacity. Our results also indicate that while evaporation from built surfaces is discontinuous and intermittent, overall, these surfaces accounted for nearly 16% of latent heat fluxes (LE) at the study site during the study period. More importantly, this contribution is mainly concentrated during the 48 hours following a rain event and thus its accurate representation is critical to our understanding of the urban surface energy budget during wet periods.
Ramamurthy, P.; Bou-Zeid, E.; Smith, J. A.; Baeck, M. L.; Welty, C.
Edge multi-facet pumping configuration for thin gain lasers
NASA Astrophysics Data System (ADS)
In this article an edge-facet and multi aperture pumped thin gain laser with highly efficient and simple pump optics is reported. The crystal configuration is a symmetrical hexagonal Composite Yb:YAG/YAG with slanted sides. Three diodes are placed outside the hexagonal shape disk, and the emitting light is coupled via three lens ducts through its three slanted edges and propagates through the disk along the zigzag path and repeatedly passes the gain medium, thus pump uniformity and absorption efficiency are improved. A comprehensive numerical model is utilized in the laser designing process. 192 W output power with good beam quality was achieved from this laser configuration.
Javadi-Dashcasan, M.; Hajiesmaeilbaighi, F.
Model for reflection and transmission matrices of nanowire end facets
NASA Astrophysics Data System (ADS)
Nanowires show a large potential for various electro-optical devices, such as light emitting diodes, solar cells, and nanowire lasers. We present a method developed to calculate the modal reflection and transmission matrix at the end facets of a waveguide of arbitrary cross-section, resulting in a generalized version of the Fresnel equations. The reflection can be conveniently computed using fast Fourier transforms once the waveguide modes are known. We demonstrate that the reflection coefficient is qualitatively described by two main parameters: the modal field confinement and the average Fresnel reflection of the plane waves constituting the waveguide mode.
Svendsen, Guro K.; Weman, Helge; Skaar, Johannes
CD133 and membrane microdomains: Old facets for future hypotheses
Understanding all facets of membrane microdomains in normal and cancerous cells within the digestive tract is highly important, not only from a clinical point of view, but also in terms of our basic knowledge of cellular transformation. By studying the normal and cancer stem cell-associated molecule CD133 (prominin-1), novel aspects of the organization and dynamics of polarized epithelial cells have been revealed during the last decade. Its association with particular membrane microdomains is highly relevant in these contexts and might also offer new avenues in diagnosis and/or targeting of cancer stem cells.
Fargeas, Christine A; Karbanova, Jana; Jaszai, Jozsef; Corbeil, Denis
CD133 and membrane microdomains: old facets for future hypotheses.
Understanding all facets of membrane microdomains in normal and cancerous cells within the digestive tract is highly important, not only from a clinical point of view, but also in terms of our basic knowledge of cellular transformation. By studying the normal and cancer stem cell-associated molecule CD133 (prominin-1), novel aspects of the organization and dynamics of polarized epithelial cells have been revealed during the last decade. Its association with particular membrane microdomains is highly relevant in these contexts and might also offer new avenues in diagnosis and/or targeting of cancer stem cells. PMID:22039332
Fargeas, Christine A; KarbanovÃ, Jana; JÃszai, Jµzsef; Corbeil, Denis
Third-degree burn from cooled radiofrequency ablation of medial branch nerves for treatment of thoracic facet syndrome.
Radiofrequency ablation of medial branch nerves is considered a safe and effective treatment for chronic facet joint pain in the cervical, thoracic, and lumbosacral spine. Cooled radiofrequency ablation (C-RFA) is gaining popularity over conventional thermal radiofrequency ablation (RFA) in pain management. However, complications of C-RFA have not been reported in the literature. We present a first report of third-degree skin burn resulting from C-RFA electrode use for the treatment of facet syndrome. A 61-year-old woman (BMI of 21.8 kg/m(2) ) with thoracic facet syndrome underwent C-RFA of the T1-4 medial branch nerves (Thoracool System, Baylis Medical Company, Montreal, QC, Canada). Lesioning at the superior-lateral aspect of the thoracic transverse processes at each level was performed. During lesioning of the T2 MBN on the T3 transverse process, skin blanching 15 mm in diameter was noted around the introducer needle with patient complaints of severe, localized pain. Postprocedurally the skin injury at this level worsened in appearance, with a 20 mm æ 4 mm skin defect, which took nearly 5 months to heal. With C-RFA, internally cooled electrodes are capable of creating large volume spherical lesions, a size advantage over conventional RFA. Although C-RFA lesion size may overcome the anatomic variability of target nerve location and potentially improve pain outcomes, added vigilance is required in thin patients and in anatomic regions of minimal subcutaneous tissue between the lesion target and the dermis. Skin burns at the site of the RF electrode are a potential risk under such conditions. PMID:24796394
Walega, David; Roussis, Christiana
Knee joint moments in work-related situations.
Circumstantial evidence in the literature points towards a relationship between heavy labour and arthrosis of the knee. The aim of this study was to demonstrate which occupational activities yield the greatest knee moments and thus indicate possible gonarthrosis-inducing occupational hazards. Twelve healthy and uninjured medical students were studied in set occupational situations in a laboratory for gait analysis, using a force plate with video display of force vectors and knee joints (VIFOR). With normal walking as a baseline for moment it was found that activities involving knee flexion, such as lifting objects from one level to the other, climbing stairs and ladders, and jumping down, revealed a significant increase in moment. On the other hand, carrying objects in one or both hands did not yield significant increase in knee moment compared with normal walking. Flexed knee lifting had significantly lower moment than jumping down from a height of 0.5 m on to one or both feet. Three levels of knee moment could thus be identified, i.e., normal walking, flexed knee lifting and jumping down. PMID:7635126
Sahlstr—m, A; Lanshammar, H; Adalberth, G
[Operative treatment of cartilage lesions in the knee joint].
With regard to the current demographic changes in today's population and the increasing demands of the patients i. e. in sports activity, the operative treatment of chondral lesions gained of importance in recent years. The treatment of cartilage injuries is not only of great importance in order to reduce the patients' symptoms, but also intends to avoid the appearance of secondary arthrosis. There are several different techniques available for the treatment of full-thickness defects (such as microfracture and autologous chondrocyte implantation), some of them following related principles. The choice of the optimal treatment technique remains of great importance and represents one of the major responsibilities of the surgeon in order to achieve optimal results. The current article represents a review of current techniques and developments in operative cartilage repair of the knee joint and gives help in the decision-making process, since the use of the appropriate technique becomes more and more important in order to achieve optimal clinical results. PMID:17385104
Niemeyer, P; Kreuz, P C; Steinwachs, M; S■dkamp, N P
Joint pain may result from traumas or repeated microtraumas, as in sports injuries. Pain in osteoarthritis starts before any\\u000a objective finding. It has been demonstrated that in the first stages of this disease, pain is due to intraosseous venous engorgement\\u000a for the earlier thickening of the cortical bone under the articular cartilage. The mechanisms of inflammatory pain are more\\u000a complex
Massimo Zoppi; Elisabetta Beneforti
Tailoring molecular specificity toward a crystal facet: a lesson from biorecognition toward Pt{111}.
Surfactants with preferential adsorption to certain crystal facets have been widely employed to manipulate morphologies of colloidal nanocrystals, while mechanisms regarding the origin of facet selectivity remain an enigma. Similar questions exist in biomimetic syntheses concerning biomolecular recognition to materials and crystal surfaces. Here we present mechanistic studies on the molecular origin of the recognition toward platinum {111} facet. By manipulating the conformations and chemical compositions of a platinum {111} facet specific peptide, phenylalanine is identified as the dominant motif to differentiate {111} from other facets. The discovered recognition motif is extended to convert nonspecific peptides into {111} specific peptides. Further extension of this mechanism allows the rational design of small organic molecules that demonstrate preferential adsorption to the {111} facets of both platinum and rhodium nanocrystals. This work represents an advance in understanding the organic-inorganic interfacial interactions in colloidal systems and paves the way to rational and predictable nanostructure modulations for many applications. PMID:23320831
Ruan, Lingyan; Ramezani-Dakhel, Hadi; Chiu, Chin-Yi; Zhu, Enbo; Li, Yujing; Heinz, Hendrik; Huang, Yu
Facility for Advanced Accelerator Experimental Tests (FACET) at SLAC and its Radiological Considerations
Facility for Advanced Accelerator Experimental Tests (FACET) in SLAC will be used to study plasma wakefield acceleration. FLUKA Monte Carlo code was used to design a maze wall to separate FACET project and LCLS project to allow persons working in FACET side during LCLS operation. Also FLUKA Monte Carlo code was used to design the shielding for FACET dump to get optimum design for shielding both prompt and residual doses, as well as reducing environmental impact. FACET will be an experimental facility that provides short, intense pulses of electrons and positrons to excite plasma wakefields and study a variety of critical issues associated with plasma wakefield acceleration [1]. This paper describes the FACET beam parameters, the lay-out and its radiological issues.
Mao, X.S.; Leitner, M.Santana; Vollaire, J.
Intensity Effects of the FACET Beam in the SLAC Linac
The beam for FACET (Facility for Advanced aCcelerator Experimental Tests) at SLAC requires an energy-time correlation ('chirp') along the linac, so it can be compressed in two chicanes, one at the midpoint in sector 10 and one W-shaped chicane just before the FACET experimental area. The induced correlation has the opposite sign to the typical used for BNS damping, and therefore any orbit variations away from the center kick the tail of the beam more than the head, causing a shear in the beam and emittance growth. Any dispersion created along the linac has similar effects due to the high (>1.2% rms) energy spread necessary for compression. The initial huge emittances could be reduced by a factor of 10, but were still bigger than expected by a factor of 2-3. Normalized emittance of 3 {micro}m-rad in Sector 2 blew up to 150 {micro}m-rad in Sector 11 but could be reduced to about 6-12 {micro}m-rad, for the vertical plane although the results were not very stable. Investigating possible root causes for this, we found locations where up to 10 mm dispersion was created along the linac, which were finally verified with strong steering and up to 7 mm settling of the linac accelerator at these locations.
Decker, F.-J.; Lipkowitz, N.; Sheppard, J.; White, G.R.; Wienands, U.; Woodley, M.; Yocky, G.; /SLAC
Interactive exploration of implicit and explicit relations in faceted datasets.
Many datasets, such as scientific literature collections, contain multiple heterogeneous facets which derive implicit relations, as well as explicit relational references between data items. The exploration of this data is challenging not only because of large data scales but also the complexity of resource structures and semantics. In this paper, we present PivotSlice, an interactive visualization technique which provides efficient faceted browsing as well as flexible capabilities to discover data relationships. With the metaphor of direct manipulation, PivotSlice allows the user to visually and logically construct a series of dynamic queries over the data, based on a multi-focus and multi-scale tabular view that subdivides the entire dataset into several meaningful parts with customized semantics. PivotSlice further facilitates the visual exploration and sensemaking process through features including live search and integration of online data, graphical interaction histories and smoothly animated visual state transitions. We evaluated PivotSlice through a qualitative lab study with university researchers and report the findings from our observations and interviews. We also demonstrate the effectiveness of PivotSlice using a scenario of exploring a repository of information visualization literature. PMID:24051774
Zhao, Jian; Collins, Christopher; Chevalier, Fanny; Balakrishnan, Ravin
Comparing Linkage Designs Based on Land Facets to Linkage Designs Based on Focal Species
Least-cost modeling for focal species is the most widely used method for designing conservation corridors and linkages. However, these designs depend on today's land covers, which will be altered by climate change. We recently proposed an alternative approach based on land facets (recurring landscape units of relatively uniform topography and soils). The rationale is that corridors with high continuity of individual land facets will facilitate movement of species associated with each facet today and in the future. Conservation practitioners might like to know whether a linkage design based on land facets is likely to provide continuity of modeled breeding habitat for species needing connectivity today, and whether a linkage for focal species provides continuity and interspersion of land facets. To address these questions, we compared linkages designed for focal species and land facets in three landscapes in Arizona, USA. We used two variables to measure linkage utility, namely distances between patches of modeled breeding habitat for 516 focal species in each linkage, and resistance profiles for focal species and land facets between patches connected by the linkage. Compared to focal species designs, linkage designs based on land facets provided as much or more modeled habitat connectivity for 25 of 28 species-landscape combinations, failing only for the three species with the most narrowly distributed habitat. Compared to land facets designs, focal species linkages provided lower connectivity for about half the land facets in two landscapes. In areas where a focal species approach to linkage design is not possible, our results suggest that conservation practitioners may be able to implement a land facets approach with some confidence that the linkage design would serve most potential focal species. In areas where focal species designs are possible, we recommend using the land facet approach to complement, rather than replace, focal species approaches.
Brost, Brian M.; Beier, Paul
Differential Relations of Depression and Social Anxiety Symptoms to the Facets of Extraversion\\/Positive Emotionality
Previous research has shown that both depression and social anxiety2 facets of internalizing psychopathologyare characterized by low levels of extraversion\\/positive emotionality (E\\/PE). However, little is known about the relations of the facets of E\\/PE with the symptoms of depression and social anxiety. This study utilized multiple measures of each facet of E\\/PE, as well as depression and social anxiety symptoms.
Kristin Naragon-Gainey; David Watson; Kristian E. Markon
Nonlinear elastic model for faceting of vesicles with soft grain boundaries.
We use an elastic model to explore faceting of solid-wall vesicles with elastic heterogeneities. We show that faceting occurs in regions where the vesicle wall is softer, such as areas of reduced wall thicknesses or concentrated in crystalline defects. The elastic heterogeneities are modeled as a second component with reduced elastic parameters. Using simulated annealing Monte Carlo simulations we obtain the vesicle shape by optimizing the distributions of facets and boundaries. Our model allows us to reduce the effects of the residual stress generated by crystalline defects, and reveals a robust faceting mechanism into polyhedra other than the icosahedron. PMID:23004693
Sknepnek, Rastko; Olvera de la Cruz, Monica
FACET: an object-oriented software framework for modeling complex social behavior patterns
The Framework for Addressing Cooperative Extended Transactions (FACET) is a flexible, object-oriented architecture for implementing models of dynamic behavior of multiple individuals, or agents, in a simulation. These agents can be human (individuals or organizations) or animal and may exhibit any type of organized social behavior that can be logically articulated. FACET was developed by Argonne National Laboratory's (ANL) Decision and Information Sciences Division (DIS) out of the need to integrate societal processes into natural system simulations. The FACET architecture includes generic software components that provide the agents with various mechanisms for interaction, such as step sequencing and logic, resource management, conflict resolution, and preemptive event handling. FACET components provide a rich environment within which patterns of behavior can be captured in a highly expressive manner. Interactions among agents in FACET are represented by Course of Action (COA) object-based models. Each COA contains a directed graph of individual actions, which represents any known pattern of social behavior. The agents' behavior in a FACET COA, in turn, influences the natural landscape objects in a simulation (i.e., vegetation, soil, and habitat) by updating their states. The modular design of the FACET architecture provides the flexibility to create multiple and varied simulation scenarios by changing social behavior patterns, without disrupting the natural process models. This paper describes the FACET architecture and presents several examples of FACET models that have been developed to assess the effects of anthropogenic influences on the dynamics of the natural environment.
Dolph, J. E.; Christiansen, J. H.; Sydelko, P. J.
Aerodynamics Investigation of Faceted Airfoils at Low Reynolds Number
NASA Astrophysics Data System (ADS)
The desire and demand to fly farther and faster has progressively integrated the concept of optimization with airfoil design, resulting in increasingly complex numerical tools pursuing efficiency often at diminishing returns; while the costs and difficulty associated with fabrication increases with design complexity. Such efficiencies may often be necessary due to the power density limitations of certain aircraft such as small unmanned aerial vehicles (UAVs) and micro air vehicles (MAVs). This research, however, focuses on reducing the complexity of airfoils for applications where aerodynamic performance is less important than the efficiency of manufacturing; in this case a Hybrid Projectile. By employing faceted sections to approximate traditional contoured wing sections it may be possible to expedite manufacturing and reduce costs. We applied this method to the development of a low Reynolds number, disposable Hybrid Projectile requiring a 4.5:1 glide ratio, resulting in a series of airfoils which are geometric approximations to highly contoured cross-sections called ShopFoils. This series of airfoils both numerically and experimentally perform within a 10% margin of the SD6060 airfoil at low Re. Additionally, flow visualization has been conducted to qualitatively determine what mechanisms, if any, are responsible for the similarity in performance between the faceted ShopFoil sections and the SD6060. The data obtained by these experiments did not conclusively reveal how the faceted surfaces may influence low Re flow but did indicate that the ShopFoil s did not maintain flow attachment at higher angles of attack than the SD6060. Two reasons are provided for the unexpected performance of the ShopFoil: one is related to downwash effects, which are suspected of placing the outer portion of the span at an effective angle of attack where the ShopFoils outperform the SD6060; the other is the influence of the tip vortex on separation near the wing tips, which possibly provides a 'comparative advantage' to the ShopFoil because it has more to gain from a reduction in its pressure drag component.
Napolillo, Zachary G.
Oxidation of CO by NO on planar and faceted Ir(210).
Oxidation of CO by pre-adsorbed NO has been studied on planar Ir(210) and nanofaceted Ir(210) with average facet sizes of 5 nm and 14 nm by temperature programmed desorption (TPD). Both surfaces favor oxidation of CO to CO(2), which is accompanied by simultaneous reduction of NO with high selectivity to N(2). At low NO pre-coverage, the temperature (T(i)) for the onset of CO(2) desorption as well as CO(2) desorption peak temperature (T(p)) decreases with increasing CO exposure, and NO dissociation is affected by co-adsorbed CO. At high NO pre-coverage, T(i) and T(p) are independent of CO exposure, and co-adsorbed CO has no influence on dissociation of NO. Moreover, at low NO pre-coverage, planar Ir(210) is more active than faceted Ir(210) for oxidation of CO to CO(2): T(i) and T(p) are much lower on planar Ir(210) than that on faceted Ir(210). In addition, faceted Ir(210) with an average facet size of 5 nm is more active for oxidation of CO to CO(2) than faceted Ir(210) with an average facet size of 14 nm, i.e., oxidation of CO by pre-adsorbed NO on faceted Ir(210) exhibits size effects on the nanometer scale. In comparison, at low O pre-coverage planar Ir(210) is more active than faceted Ir(210) for oxidation of CO to CO(2) but no evidence has been found for size effects in oxidation of CO by pre-adsorbed oxygen on faceted Ir(210) for average facet sizes of 5 nm and 14 nm. The TPD data indicate the same reaction pathway for CO(2) formation from CO + NO and CO + O reactions on planar Ir(210). The adsorption sites of CO, NO, O, CO + O, and CO + NO on Ir are characterized by density functional theory. PMID:22713063
Chen, Wenhua; Bartynski, Robert A; Kaghazchi, Payam; Jacob, Timo
Giant photoluminescence emission in crystalline faceted Si grains
Empowering an indirect band-gap material like Si with optical functionalities, firstly light emission, represents a huge advancement constantly pursued in the realization of any integrated photonic device. We report the demonstration of giant photoluminescence (PL) emission by a newly synthesized material consisting of crystalline faceted Si grains (fg-Si), a hundred nanometer in size, assembled in a porous and columnar configuration, without any post processing. A laser beam with wavelength 632.8?nm locally produce such a high temperature, determined on layers of a given thickness by Raman spectra, to induce giant PL radiation emission. The optical gain reaches the highest value ever, 0.14?cm/W, representing an increase of 3 orders of magnitude with respect to comparable data recently obtained in nanocrystals. Giant emission has been obtained from fg-Si deposited either on glass or on flexible, low cost, polymeric substrate opening the possibility to fabricate new devices.
Faraci, Giuseppe; Pennisi, Agata R.; Alberti, Alessandra; Ruggeri, Rosa; Mannino, Giovanni
Reverse epitaxy of Ge: ordered and faceted surface patterns.
Normal incidence ion irradiation at elevated temperatures, when amorphization is prevented, induces novel nanoscale patterns of crystalline structures on elemental semiconductors by a reverse epitaxial growth mechanism: on Ge surfaces irradiation at temperatures above the recrystallization temperature of 250 ¯C leads to self-organized patterns of inverse pyramids. Checkerboard patterns with fourfold symmetry evolve on the Ge (100) surface, whereas on the Ge (111) surface, isotropic patterns with a sixfold symmetry emerge. After high-fluence irradiations, these patterns exhibit well-developed facets. A deterministic nonlinear continuum equation accounting for the effective surface currents due to an Ehrlich-Schwoebel barrier for diffusing vacancies reproduces remarkably well our experimental observations. PMID:23863015
Ou, Xin; Keller, Adrian; Helm, Manfred; Fassbender, J■rgen; Facsko, Stefan
The Measurement of Writing Ability with a Many-Faceted Rasch Model.
ERIC Educational Resources Information Center
A Many-Faceted Rasch Model (FACETS) for measurement of writing ability is described, and its use in solving measurement problems in large-scale assessment is illustrated with a random sample of 1,000 students from Georgia's Eighth Grade Writing Test. It is a promising approach to assessment through written compositions. (SLD)
Engelhard, George, Jr.
Soft tissue injuries associated with traumatic locked facets in the cervical spine
The clinical, radiological and operative findings in 10 consecutive patients with cervical spine trauma presenting with locked facets (bilaterally in nine patients) are reported. The treatment was cervical traction until reduction of the locked facets was achieved, followed by anterior surgical decompression and ostheosynthesis. Intervertebral disc herniation was present in nine of the patients, and ruptured calcified posterior longitudinal ligament
A C Moraes; A Serdeira; A Pereira Filho; E Zardo; J Deitos
Future-Time Perspective: Analysis of a Facet-Designed Questionnaire
Future-time perspective for adolescents and young adults is directed towards several objects and may extend into the far or the near future. Differences in this perspective can affect motivational qualities influencing investment in one's future. A future-time perspective questionnaire was developed along these lines using facet design. It contains an object facet with the elements school and professional career, personal
Marlies E. A. Stouthard; Thea T. D. Peetsma
Facile Synthesis of Gold Nanorice Enclosed by High- Index Facets and Its Application for CO Oxidation
A facile method for generating Au nanorice enclosed by high-index facets in high purity. The nanorice shows much higher catalytic activity for CO oxidation than multiply twinned particles of Au enclosed by {l_brace}111{r_brace} facets at temperatures below 300 C.
Zheng, Y.; Tao, J.; Liu, H.; Zeng, J.; Yu, T.; Ma, Y.; Moran, C.; Wu, L.; Zhu, Y.; Liu, J.; Xia, Y.
Relating Sense of Humor to the Five Factor Theory Personality Domains and Facets
The present study examined the relationships between the broad, multidimensional view of humor using the factors of the Multidimensional Sense of Humor Scale (MSHS) and all of the Five Factor Theory (FFT) personality domains and specific facets. Results indicated a number of significant personality facets related to the Humor Production and Social Use factor. The strongest were Assertiveness, Activity-level, Cheerfulness,
Andrew Johnson; David M. McCord
Study of Faceted Blog Distillation -- PRIS at TREC 2009 Blog Track.
National Technical Information Service (NTIS)
This paper describes BUPT (pris) participation in faceted blog distillation task at Blog Track 2009. The system adopts a two-stage strategy in faceted blog distillation task. In the first stage, the system carries out a basic topic relevance retrieval to ...
F. Chen H. Gao H. Sun J. Gao S. Li
The relationship of facets of salesperson job satisfaction with affective organizational commitment
Purpose This paper aims to examines the relationships between various facets of salesperson job satisfaction as assessed by the INDSALES measure and salesperson organizational commitment. The paper also seeks to explore salesperson gender as a moderator of the relationship between facets of job satisfaction and organizational commitment. Design\\/methodology\\/approach This study uses survey research of one firm's business-to-business salespeople
James Boles; Ramana Madupalli; Brian Rutherford; John Andy Wood
Scattering matrix calculated in geometric optics approximation for semitransparent particles faceted with various shapes
A new computer model of light scattering by semitransparent particles with arbitrary shape is presented. The model allows calculations of scattering angle dependences of all elements of scattering matrix Fik in geometric optics approximation. Scattering properties of faceted spheres with a number of the facets less than 10,000 differ significantly from those of the perfect spherical particles. The scattering angle
Ye. Grynko; Yu. Shkuratov
Facet effect manifestation during crystallization from small volumes of solution in melt
NASA Astrophysics Data System (ADS)
Manifestations of the facet effect are possible during the thermomigration of discrete inclusions of the solution of a growing crystal material in small volumes of the melt of a solvent metal. Similar to the case of a bulk crystal growth, the facet effect in small volumes is related to the nonequilibrium trapping of impurity by singular regions of the crystallization front.
Gershanov, V. Yu.; Garmashov, S. I.
Two-faceted mirror for active integration of coherent high-power laser beams
A new integration method suited for spatially coherent high-power laser beams is demonstrated. The integrator system is based on a mirror with two facets, one of which can vibrate under the action of a piezoelectric translator. After reflection in the faceted mirror, the beam intensity distribution is modified to obtain greater uniformity. However, because of the coherence of the reflected
J. Armengol; F. Vega; N. Lupon; F. Laguarta
Examining Rater Errors in the Assessment of Written Composition with a Many-Faceted Rasch Model.
ERIC Educational Resources Information Center
Rater errors (rater severity, halo effect, central tendency, and restriction of range) are described, and criteria are presented for evaluating rating quality based on a many-faceted Rasch (FACETS) model. Ratings of 264 compositions from the Eighth Grade Writing Test in Georgia by 15 raters illustrate the discussion. (SLD)
Engelhard, George, Jr.
A wideband multibeam faceted antenna system for integration in small platforms
The general system architecture and subsystem blocks for a wideband faceted multibeam antenna system intended for both receiving (Rx) and transmitting (Tx) functions are presented. Each facet in the antenna system consists of a planar microstrip antenna array, T\\/R-module and a Rotman lens used for 1D beam steering in azimuth; a module for pulse descriptor word (PDW) generation which detects
Lars-Gunnar Huss; Aziz Ouacha; Ronny Gunnarsson; Staffan Lindstrom; Carl Samuelsson; Mattias Alfredsson
Revealing feelings: Facets of emotional expressivity in self-reports, peer ratings, and behavior
Drawing on an explicit model of emotion, we propose a multifaceted approach to emotional expressiv- ity, defined as the behavioral (e.g., facial, postural) changes associated with emotion. Study 1 shows that self-reported expressivity has 3 facets (Impulse Strength, Negative Expressivity, Positive Expressivity). Study 2 shows that the same 3 facets emerge in peer ratings and that there are robust relations
James J. Gross; Oliver P. John
Facet effect of single-crystalline Ag3PO4 sub-microcrystals on photocatalytic properties.
We recently reported that Ag(3)PO(4) exhibits excellent photooxidative capabilities for O(2) evolution from water and organic dye decomposition under visible-light irradiation. However, very little is known about the shape and facet effects of Ag(3)PO(4) crystals on their photocatalytic properties. Herein we have developed a facile and general route for high-yield fabrication of single-crystalline Ag(3)PO(4) rhombic dodecahedrons with only {110} facets exposed and cubes bounded entirely by {100} facets. Moreover, studies of their photocatalytic performance have indicated that rhombic dodecahedrons exhibit much higher activities than cubes for the degradation of organic contaminants, which may be primarily ascribed to the higher surface energy of {110} facets (1.31 J/m(2)) than of {100} facets (1.12 J/m(2)). PMID:21486031
Bi, Yingpu; Ouyang, Shuxin; Umezawa, Naoto; Cao, Junyu; Ye, Jinhua
Faceting in bond-oriented systems with icosahedral and decagonal symmetry
NASA Astrophysics Data System (ADS)
The recent discoveries of large facets in Al-Li-Cu and other icosahedral quasicrystals, as well as the observation of spatial disorder in these systems, show that disordered systems with long-range bond-orientational order can have growth facets. A fundamental question which naturally arises is whether such systems have equilibrium facets. In this paper, we study the conditions under which a perfect bond-oriented system can facet at T=0. The T=0 equilibrium shapes of bond-oriented systems with icosahedral and decagonal bond-orientational order are discussed. An explicit example is presented to show that disordered systems can have equilibrium facets at T=0. We also give detailed derivation of the surface energy of quasicrystals.
Ho, T. L.; Li, Y. H.; Saam, W. F.; Jaszczak, J. A.
Evolution of (001) and (111) facets for selective epitaxial growth inside submicron trenches
NASA Astrophysics Data System (ADS)
The evolution of (001) and (111) facets for the epitaxial growth inside submicron trenches is systematically studied in this report. The analysis with the method of "Lagrange multiplier" indicates the equilibrium crystal shape. In the case of non-equilibrium without external fluxes, we employed the "weighted mean curvature" method to mathematically model the inter-facet migration rate for two extreme kinetic cases: "surface diffusion limited" and "surface attachment/detachment limited." Coupled with external supply of atoms, the self-limited behavior of facet size is theoretically predicted. Moreover, we find that the self-limited stable facet size in trenches of different widths has a specific relationship determined by the surface energy ratio, kinetic rate ratio, and isolated growth rate difference. The two limited cases could be discriminated according to the mathematical fitting of one exponent in this relationship based on the stable facet size in trenches of different widths.
Jiang, S.; Merckling, C.; Guo, W.; Waldron, N.; Caymax, M.; Vandervorst, W.; Seefeldt, M.; Heyns, M.
Nucleation and Growth During Faceting of the Platinum Covered W(111) Surface
Low energy electron microscopy (LEEM) and scanning tunneling microscopy (STM) have been used to investigate the faceting of W(111) as induced by Pt. The atomically rough W(111) surface, when fully covered with a monolayer film of Pt and annealed to temperatures higher than {approximately}750 K, experiences a significant morphological restructuring: the initially planar surface undergoes a faceting transition and forms three-sided pyramids with {l_brace}211{r_brace} faces. When Pt is dosed onto the heated surface, the transition from planar to faceted structure proceeds through the nucleation and growth of spatially separated faceted regions, as shown by LEEM. STM reveals the atomic structure of the partially faceted surface, with large planar regions, dotted by clusters of pyramids of various sizes.
Hannon, J.B.; Kellogg, G.L.; Madey, T.E.; Pelhos, K.
Measured and predicted root-mean-square errors in square and triangular antenna mesh facets
NASA Technical Reports Server (NTRS)
Deflection shapes of square and equilateral triangular facets of two tricot-knit, gold plated molybdenum wire mesh antenna materials were measured and compared, on the basis of root mean square (rms) differences, with deflection shapes predicted by linear membrane theory, for several cases of biaxial mesh tension. The two mesh materials contained approximately 10 and 16 holes per linear inch, measured diagonally with respect to the course and wale directions. The deflection measurement system employed a non-contact eddy current proximity probe and an electromagnetic distance sensing probe in conjunction with a precision optical level. Despite experimental uncertainties, rms differences between measured and predicted deflection shapes suggest the following conclusions: that replacing flat antenna facets with facets conforming to parabolically curved structural members yields smaller rms surface error; that potential accuracy gains are greater for equilateral triangular facets than for square facets; and that linear membrane theory can be a useful tool in the design of tricot knit wire mesh antennas.
Fichter, W. B.
Studies of the periodic faceting of epitaxial molybdenum oxide grown on Mo(110)
NASA Astrophysics Data System (ADS)
We show that an oxide film can undergo a periodic self-faceting regime during growth. The oxide growth starts as a bulklike MoO2 surface oxide trilayer that wets the substrate in an orientation thermodynamically forbidden in the bulk. As this film continues to grow, it develops into a periodically faceted surface with nanowirelike structures composed of MoO2 (0 2 1) and (02-1) faces. Through the use of density functional theory, it is found that this faceted surface has a lower surface free energy than the initial growth orientation. Finally, using the theory of faceted surfaces, we demonstrate that the periodicity of the facets is likely an equilibrium state that is related to the elastic properties of the film.
Radican, K.; Berdunov, N.; Shvets, I. V.
Analysis of trabecular microarchitecture of human iliac bone using microcomputed tomography in patients with hip arthrosis with or without vertebral fracture
Iliac bone samples were obtained from 50 women with osteoarthrosis of the hip (5080 years of age) during hip surgery for total hip joint replacement. After determining the resolution and threshold for the binary image, the two-dimensional (2D) and three-dimensional (3D) data of the trabecular structure were obtained in these iliac bone samples using microcomputed tomography (micro-CT). Conventional histomorphometry was
M Ito; T Nakamura; T Matsumoto; K Tsurusaki; K Hayashi
Jointness: A Selected Bibliography.
National Technical Information Service (NTIS)
JDEIS is the Joint Doctrine, Education and Training Community Electronic Information System. It encompasses a searchable Joint Doctrine Database, a Joint Education section that includes the JPME Prospective Research Topics Database, as well as award-winni...
L. Garder
Joint Advanced Warfighting School.
National Technical Information Service (NTIS)
When the United States employs military power, it does so as a joint force. The cornerstone for effective joint force employment remains Service competency, but truly effective Service warfighters must think, plan and fight jointly. The key to developing ...
J. M. Davis K. C. Bowen L. W. Schonenberg
Understanding Joint Warfighting Experiments.
National Technical Information Service (NTIS)
In October 1998 the United States Joint Forces Command (USJFCOM) established a Joint Warfighting Experimentation program to support Joint Concept Development. Experimentation is the unique scientific method for establishing whether hypothesized concepts a...
R. A. Kass
Arthritis: Metacarpophalangeal (MP) Joint
... Z Hand Anatomy Find a Hand Surgeon Arthritis - MP Joint Email to a friend * required fields From * ... drift (See Figure 2). When arthritis affects the MP joints, the condition is called MP joint arthritis. ...
NASA Technical Reports Server (NTRS)
Joints for use in interconnecting adjacent segments of an hermetically sealed spacesuit which have low torques, low leakage and a high degree of reliability are described. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics. Linkages which restrain the joint from longitudinal distension and a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli are featured. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.
Vykukal, H. C. (inventor)
Workflow in interventional radiology: nerve blocks and facet blocks
NASA Astrophysics Data System (ADS)
Workflow analysis has the potential to dramatically improve the efficiency and clinical outcomes of medical procedures. In this study, we recorded the workflow for nerve block and facet block procedures in the interventional radiology suite at Georgetown University Hospital in Washington, DC, USA. We employed a custom client/server software architecture developed by the Innovation Center for Computer Assisted Surgery (ICCAS) at the University of Leipzig, Germany. This software runs in an internet browser, and allows the user to record the actions taken by the physician during a procedure. The data recorded during the procedure is stored as an XML document, which can then be further processed. We have successfully gathered data on a number if cases using a tablet PC, and these preliminary results show the feasibility of using this software in an interventional radiology setting. We are currently accruing additional cases and when more data has been collected we will analyze the workflow of these procedures to look for inefficiencies and potential improvements.
Siddoway, Donald; Ingeholm, Mary Lou; Burgert, Oliver; Neumuth, Thomas; Watson, Vance; Cleary, Kevin
The many facets of PPAR?: novel insights for the skeleton
Peroxisome proliferator-activated receptor-? (PPAR?) is a nuclear receptor that functions as a master transcriptional regulator of adipocyte conversion. During PPAR? transactivation, multiple signaling pathways interact with one another, leading to the differentiation of both white and brown adipose tissue. Ligand activation of the PPAR?-RXR heterodimer complex also enhances insulin sensitivity, and this property has been heavily exploited to develop effective pharmacotherapies for the treatment of type 2 diabetes mellitus. PPAR? is also expressed in stem cells and plays a critical role in mesenchymal stromal cell differentiation and lineage determination events. The many facets of PPAR? activity within the bone marrow niche where adipocytes, osteoblasts, and hematopoietic cells reside make this molecule an attractive target for pharmacological investigation. Additional findings that osteoblasts can alter energy metabolism by influencing adiposity and insulin sensitivity, and observations of decreased bone turnover in diabetic subjects, underscore the contribution of the skeleton to systemic energy requirements. Studies into the role of PPAR? in skeletal acquisition and maintenance may lead to a better understanding of the molecular mechanisms governing stromal cell differentiation in the mesenchyme compartment and whether PPAR? activity can be manipulated to benefit skeletal remodeling events and energy metabolism.
Kawai, Masanobu; Sousa, Kyle M.; MacDougald, Ormond A.
Granular packings of elongated faceted particles deposited under gravity
NASA Astrophysics Data System (ADS)
We report experimental and theoretical results of the effect that particle shape has on the packing properties of granular materials. We have systematically measured the particle angular distribution, the cluster size distribution and the stress profiles of ensembles of faceted elongated particles deposited in a bidimensional box. Stress transmission through this granular system has been numerically simulated using a two-dimensional model of irregular particles. For grains of maximum symmetry (squares), the stress propagation localizes and forms chain-like forces analogous to those observed for granular materials composed of spheres. For thick layers of grains, a pressure saturation is observed for deposit depths beyond a characteristic length. This scenario correlates with packing morphology and can be understood in terms of stochastic models of aggregation and random multiplicative processes. As grains elongate and lose their symmetry, stress propagation is strongly affected. Lateral force transmission becomes less favored than vertical transfer, and hence, an increase in the pressure develops with depth, hindering force saturation.
Cruz Hidalgo, Raºl; Zuriguel, Iker; Maza, Diego; Pagonabarraga, Ignacio
Utility of Helical Computed Tomography in Differentiating Unilateral and Bilateral Facet Dislocations
Objective: Diagnosis of cervical facet dislocation is difficult when relying on plain radiographs alone. This study evaluates the interobserver reliability of helical computed tomography (CT) in the assessment of cervical translational injuries, correlates the radiographic diagnosis with intraoperative observation, and examines the role of neurologic injury in the evaluation and diagnosis of these injuries. Methods: Clinical histories and radiographic studies of 10 patients with cervical facet dislocations were presented to 25 surgeons. Participants classified cases as unilateral or bilateral facet dislocations after reviewing selected axial CT slices and sagittal reconstructions. Surgeons' interpretations were compared with intraoperative diagnosis. Participants interpreted the same radiographic studies with 3 different clinical scenarios: neurologically intact, incomplete, and complete spinal cord injury. Vertebral body translation from midsagittal CT was evaluated to confirm whether all unilateral facet dislocations had <25% translation. Results: Interrater ? coefficient showed moderate agreement between observers in classifying injuries as unilateral or bilateral (?: 0.540.58), regardless of neurologic status. Percent agreement among observers varied from 50% to 100% for each individual case. Agreement was statistically higher for bilateral facet dislocation (85%) than for unilateral dislocations (78%), with 1 unilateral fracture showing nearly 50% translation on a midsagittal image. Conclusions: The addition of helical CT to reconstruction enables spine surgeons to more reliably distinguish bilateral from unilateral cervical facet dislocations. Despite frequent occurrence of these injuries and presumed agreement on injury description, agreement may be improved by a more precise definition of facet dislocations and subluxations and thorough review of all imaging studies.
Dailey, Andrew T; Shaffrey, Christopher I; Rampersaud, Raja; Lee, Joonyung; Brodke, Darrel S; Arnold, Paul; Nassr, Ahmad; Harrop, James S; Grauer, Jonathan; Bono, Christopher M; Dvorak, Marcel; Vaccaro, Alexander
Obtaining Content Weights for Test Specifications from Job Analysis Task Surveys: An Application of the Many-Facets Rasch Model
ERIC Educational Resources Information Center
This article discusses the use of the Many-Facets Rasch Model, via the FACETS computer program (Linacre, 2006a), to scale job/practice analysis survey data as well as to combine multiple rating scales into single composite weights representing the tasks' relative importance. Results from the Many-Facets Rasch Model are compared with those
Wang, Ning; Stahl, John
Use of land facets to plan for climate change: conserving the arenas, not the actors.
Even under the most optimistic scenarios, during the next century human-caused climate change will threaten many wild populations and species. The most useful conservation response is to enlarge and link protected areas to support range shifts by plants and animals. To prioritize land for reserves and linkages, some scientists attempt to chain together four highly uncertain models (emission scenarios, global air-ocean circulation, regional circulation, and biotic response). This approach has high risk of error propagation and compounding and produces outputs at a coarser scale than conservation decisions. Instead, we advocate identifying land facets-recurring landscape units with uniform topographic and soil attributes-and designing reserves and linkages for diversity and interspersion of these units. This coarse-filter approach would conserve the arenas of biological activity, rather than the temporary occupants of those arenas. Integrative, context-sensitive variables, such as insolation and topographic wetness, are useful for defining land facets. Classification procedures such as k-means or fuzzy clustering are a good way to define land facets because they can analyze millions of pixels and are insensitive to case order. In regions lacking useful soil maps, river systems or riparian plants can indicate important facets. Conservation planners should set higher representation targets for rare and distinctive facets. High interspersion of land facets can promote ecological processes, evolutionary interaction, and range shift. Relevant studies suggest land-facet diversity is a good surrogate for today's biodiversity, but fails to conserve some species. To minimize such failures, a reserve design based on land facets should complement, rather than replace, other approaches. Designs based on land facets are not biased toward data-rich areas and can be applied where no maps of land cover exist. PMID:20067491
Beier, Paul; Brost, Brian
Theory of concave gratings based on a recursive definition of facet positions.
A general theory for concave gratings is presented that is based on a recursion formula for the facet positions and that differs from previous theories that are based on a power-series expansion of the light path function. In the recursion formula approach the facet positions are determined from a numerical solution for the roots of two constraint functions. Facet positions are determined in sequence, starting from the grating pole. One constraint function may be chosen to give a stigmatic point. A variety of grating designs are discussed, including a design that cannot be generated with the power-series approach. PMID:21127601
McGreer, K A
Theory of concave gratings based on a recursive definition of facet positions
NASA Astrophysics Data System (ADS)
A general theory for concave gratings is presented that is based on a recursion formula for the facet positions and that differs from previous theories that are based on a power-series expansion of the light path function. In the recursion formula approach the facet positions are determined from a numerical solution for the roots of two constraint functions. Facet positions are determined in sequence, starting from the grating pole. One constraint function may be chosen to give a stigmatic point. A variety of grating designs are discussed, including a design that cannot be generated with the power-series approach.
McGreer, K. A.
Faceting at the step flow threshold in epitaxial growth on patterned surfaces
We identify a kinetic mechanism responsible for the emergence of low-angle facets in recent epitaxial regrowth experiments on patterned surfaces. Kinetic Monte Carlo simulations of vicinal surfaces show that the preferred slope of the facets matches the threshold slope for the transition between step flow and growth by island nucleation. At this crossover slope, the surface step density is minimized and the adatom density is maximized, respectively. A model is developed that predicts the temperature dependence of the crossover slope and hence the facet slope.
Jones, Aleksy K.; Ballestad, Anders; Li, Tian; Whitwick, Michael; Rottler, Joerg; Tiedje, T. [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia, V6T 1Z1 (Canada)
[Vascularized joint transfer for finger joint reconstruction].
In a retrospective clinical study 16 vascularized joint transfers to the hand with an average follow-up of 8.2 (3 - 15) years were evaluated. The finger joint defect was caused by trauma in 12 patients, tumour in 2 patients and infection and congenital deformity in 1 patient each. There were 14 men and 2 women. The mean age range was 26 (2 - 42) years. In 6 cases a partial vascularized joint transfer was carried out, with the transplant being harvested in two cases from non-replantable finger according to the "tissue bank concept" according to Chase and in the other two cases from the PIP-joint of the second toe. In 10 patients a complete vascularized joint transfer was carried out, with the joint being harvested from the hand in 6 cases and from the 2nd toe in 4 cases. The following criteria were evaluated: active range of motion (neutral-0-method), postoperative arthritis, growth and complications. Active range of motion of the transplanted joint was for partial PIP-joint transfer Ex/Flex 0/20/65 degrees und for partial MP-joint transfer 0/20/30 degrees . After DIP-to-PIP-joint transposition active range of motion was measured Ex/Flex 0/20/60 degrees , after PIP-to-PIP transposition 0/30/60 degrees , PIP-to-MP-transposition 0/20/80 degrees and after MP-to-MP-transposition 0/20/57 degrees . The results after microvascular PIP-joint transfer from the 2nd toe for PIP-joint reconstruction were 0/25/58 degrees for PIP-joint reconstruction and 0/15/70 degrees for MP-joint reconstruction. Arthritic changes could be seen in 3 out of 4 patients with partial vascularized joint transfer. In all complete joint transfers there was no clinical and radiological evidence of arthritis even after 15 years. In the two skeletal immature patients at the time of transfer, normal growth compared to the contralateral donor site could be seen. In 8 out of 14 patients complications occurred. In 4 cases tendolysis of the extensor tendon was necessary. In 4 patients skeletal malalignment (3 x sagittal plane, 1 x rotation) was diagnosed. In one patient flexor pulley reconstruction was necessary in order to correct a bowstring deformity. Indications for vascularized joint transfer at the finger in children is set because of lack of therapy option offering normal growth potential. In adults vascularized joint transfer is indicated in case of contraindication for prosthetic joint replacement or arthrodesis. PMID:17724645
Hierner, R; Berger, A K; Shen, Z-L
Proprioception and joint stability
In the present paper the current clinical knowledge about proprioception is given for the shoulder, knee, ankle, elbow and the radiocarpal joint. Proprioceptive capabilities are decreased after joint injuries such as ACL or meniscus tears, shoulder dislocation, ankle sprain and in joints with degenerative joint disease. Some surgical procedures seem to restore the proprioceptive abilities; others do not. Elastic knee
J. Jerosch; M. Prymka
Process of faceting in nanoparticles of FCC metals: Results of simulation by the molecular-dynamics method
NASA Astrophysics Data System (ADS)
The process of formation of facets (faceting) in Ni, Al, and Au nanoparticles has been investigated by the molecular-dynamics method. It has been established that the surface of nanoparticles of fcc metals with attainment of a low-energy habit can be transformed via correlated displacements of atomic groups of the facet in the octahedral plane. It has been shown that such a process is similar to the surface diffusion of atomic n-mers with the activation energy depending on the facet size, and for particles with a diameter d < 3.0 nm the correlated displacement of atomic layers proves to be the dominant mechanism of faceting.
Kar'kina, L. E.; Kar'kin, I. N.; Gornostyrev, Yu. N.
Physical facets of ultrasonic cavitational synthesis of zinc ferrite particles.
This paper addresses the physical features of the ultrasonic cavitational synthesis of zinc ferrite particles and tries to establish the relationship between cavitation physics and sonochemistry of the zinc ferrite synthesis. A dual approach of coupling experimental results with simulations of radial motion of cavitation bubbles has been adopted. The precursors for the zinc ferrite, viz. ZnO and Fe(3)O(4) are produced in situ by the hydrolysis of Zn and Fe(II) acetates stimulated by (*)OH radicals produced from the transient collapse of the cavitation bubbles. Experiments performed under different conditions create significant variation in the production of (*)OH radicals, and hence, the rate of acetate hydrolysis. Correlation of the results of experiments and simulations sheds light on the important facets of the physical mechanism of ultrasonic cavitational zinc ferrite synthesis. It is revealed that too much or too little rate of acetate hydrolysis results in smaller particle size of zinc ferrite. The first effect of a higher rate of hydrolysis leads to excessively large growth of particles, due to which they become susceptible to the disruptive action of cavitation bubbles. Whereas, the second effect of too small rate of hydrolysis of Zn and Fe(II) acetates restricts the growth of particles. It has been observed that the initial reactant concentration does not influence the mean particle size or the size distribution of zinc ferrite particles. The present investigation clearly confirms that the rate-controlling step of zinc ferrite synthesis through ultrasonic cavitational route is the rate of formation of (*)OH radicals from cavitation bubbles. PMID:19880340
Reddy, Bhaskar Rao; Sivasankar, Thirugnanasambandam; Sivakumar, Manickam; Moholkar, Vijayanand S
Facet Model and Mathematical Morphology for Surface Characterization
This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera. This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still f ailed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel, Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be successful in detecting the various topographic characteristics of the surface of the slurry. Pertinent topographic elements are retained and a filtered image computed. Carefully tailored morphological operators are then applied to detect and segment regions of interest. Those regions are then selected according to their size, elongation, and orientation. Their bounding rectangles are computed and represented. Also addressed in this paper are aspects of the real time implementation of this algorithm for on-line use. The algorithm is tested on over 500 images of slurry and is found to segment and characterize nonuniformities on all 500 images.
Abidi, B.R.; Goddard, J.S.; Hunt, M.A.; Sari-Sarraf, H.
Control of the disease activity is enabled due to the progress of drug therapy for rheumatoid arthritis. However, surgical treatments are necessary for unresponsive cases to the drug or for achieving higher QOL, and we can attain more tight control or cure by combination of drug therapy and surgical treatments. Total joint arthroplasty provides indolence, mobility, stability and is an useful joint reconstruction method. Shoulder and elbow joint work as a reach function together, and total joint arthroplasty become adaptation when extensive joint destruction or severe pain occurrs. With the usage of biologic agents joint repair is possible in small joints, but if the joint destruction progress in weight-bearing joints, repair is impossible and total joint arthroplasty can be required. PMID:23961679
Mibe, Junya; Yamamoto, Kengo
Facet-dependent electrochemical properties of Co3O4 nanocrystals toward heavy metal ions
We revealed an interesting facet-dependent electrochemical behavior toward heavy metal ions (HMIs) based on their adsorption behaviors. The (111) facet of Co3O4 nanoplates has better electrochemical sensing performance than that of the (001) facet of Co3O4 nanocubes. Adsorption measurements and density-functional theory (DFT) calculations reveals that adsorption of HMIs is responsible for the difference of electrochemical properties. Our combined experimental and theoretical studies provide a solid hint to explain the mechanism of electrochemical detection of HMIs using nanoscale metal oxides. Furthermore, this study not only suggests a promising new strategy for designing high performance electrochemical sensing interface through the selective synthesis of nanoscale materials exposed with different well-defined facets, but also provides a deep understanding for a more sensitive and selective electroanalysis at nanomaterials modified electrodes.
Yu, Xin-Yao; Meng, Qiang-Qiang; Luo, Tao; Jia, Yong; Sun, Bai; Li, Qun-Xiang; Liu, Jin-Huai; Huang, Xing-Jiu
Pathological eating behaviors, BMI, and facet-level traits: the roles of conscientiousness, neuroticism, and impulsivity.
The current study examined the bivariate and multivariate associations of personality with Body Mass Index (BMI) and several eating behavior inventories, focusing on facets of Neuroticism, Conscientiousness, and Impulsivity. Simultaneous multiple regressions showed that the facets Traditionalism, Urgency, and low Vulnerability were significant predictors of BMI. A factor analysis of the eating behavior scales revealed two dimensions: (a) Food and Body Preoccupation and (b) Cued Eating; Neuroticism, low Conscientiousness, and Perfectionism were significant predictors of both eating behavior factors. In addition, the Depression facet predicted Food and Body Preoccupation, and low Temperance predicted Cued Eating. Implications are discussed for the structure of eating pathology and the specificity of facet traits to eating behaviors and obesity. PMID:24183129
Ellickson-Larew, Stephanie; Naragon-Gainey, Kristin; Watson, David
Facet-specific assembly of proteins on SrTiO? polyhedral nanocrystals.
Precisely controlling the protein-nanomaterial interactions at selective sites is crucial in engineering biomolecule composite architectures with tailored nanostructures and functions for a variety of biomedical applications. This strategy, however, is only beginning to be explored. Here, we demonstrate the facet-specific assembly of proteins, such as albumin, immunoglobulin and protamine, on {100} facets of SrTiO3 polyhedral nanocrystals, while none on {110} facets. Molecular dynamics simulations indicate the immobile surface hydration layer might play a barrier role to effectively prevent proteins adsorption on specific {110} facets. This work thus provides new insights into the fundamentally understanding of protein-nanomaterial interactions, and open a novel, general and facile route to control the selective adsorption of various proteins on various nanocrystals. PMID:24866740
Dong, Lingqing; Luo, Qi; Cheng, Kui; Shi, Hui; Wang, Qi; Weng, Wenjian; Han, Wei-Qiang
Microstructural characterization and formation mechanism of 21¯ top facets of ZnO-based nanowall structures
NASA Astrophysics Data System (ADS)
This study reports the microstructural characterization and formation mechanism of the 21¯ top facets of ZnO-based nanowall structures. The ZnO-based nanowall structures reported previously by many other research groups have {112bar0} planes as major planes and top facets with a specific angle in common, irrespective of the growth techniques and growth conditions. These nanowalls were found to exist between two adjacent nanowires with a c-axis preferred orientation, and the atoms at the junction of the nanowalls and nanowires perfectly coincided with each other at an atomic level, without any defects. The top facets of the nanowalls showed periodically stepped surfaces and were identified as {011bar5} planes, which were perpendicular to the {112bar0} major planes. On the basis of the microstructural characterization of the synthesized ZnO-based nanowall structures, the formation mechanism and atomic structure model of the 21¯ top facets of the nanowall structures are proposed.
Lee, Ju Ho; Kim, Dong Chan; Kim, Sang Yun; Choi, SungSoon; Lee, Kwan-Hun; Lee, Jeong Yong; Koun Cho, Hyung
Facet-Specific Assembly of Proteins on SrTiO3 Polyhedral Nanocrystals
Precisely controlling the protein-nanomaterial interactions at selective sites is crucial in engineering biomolecule composite architectures with tailored nanostructures and functions for a variety of biomedical applications. This strategy, however, is only beginning to be explored. Here, we demonstrate the facet-specific assembly of proteins, such as albumin, immunoglobulin and protamine, on {100} facets of SrTiO3 polyhedral nanocrystals, while none on {110} facets. Molecular dynamics simulations indicate the immobile surface hydration layer might play a barrier role to effectively prevent proteins adsorption on specific {110} facets. This work thus provides new insights into the fundamentally understanding of protein-nanomaterial interactions, and open a novel, general and facile route to control the selective adsorption of various proteins on various nanocrystals.
Dong, Lingqing; Luo, Qi; Cheng, Kui; Shi, Hui; Wang, Qi; Weng, Wenjian; Han, Wei-Qiang
Phase field modeling of facet formation during directional solidification of silicon film
NASA Astrophysics Data System (ADS)
Adaptive phase field modeling is conducted to study the facet formation during directional solidification of silicon film. The necessary condition for morphological instability is examined first based on the classic theory for the reported experiments. With a proper thermal gradient, the simulated onset velocity is found consistent with the experimental observations and the classic theory. The effects of anisotropy of kinetic coefficients and interfacial energy are also considered, and the simulated morphologies are significantly affected. The range of the kinetic cusp function affects the facet tips, while the anisotropy of interfacial free energy changes the wavelength of facets. Nevertheless, the simulation of kinetic undercooling on the facets is not successful, and the computational difficulty is discussed.
Lin, H. K.; Chen, H. Y.; Lan, C. W.
Fabrication of lithographically defined optical coupling facets for silicon-on-insulator waveguides by inductively coupled plasma etching
We present a technique to lithographically define and fabricate all required optical facets on a silicon-on-insulator photonic integrated circuit by an inductively coupled plasma etch process. This technique offers 1 {mu}m positioning accuracy of the facets at any location within the chip and eliminates the need of polishing. Facet fabrication consists of two separate steps to ensure sidewall verticality and minimize attack on the end surfaces of the waveguides. Protection of the waveguides by a thermally evaporated aluminum layer before the 40-70 {mu}m deep optical facet etching has been proven essential in assuring the facet smoothness and integrity. Both scanning electron microscopy analysis and optical measurement results show that the quality of the facets prepared by this technique is comparable to the conventional facets prepared by polishing.
Yap, K.P.; Lamontagne, B.; Delage, A.; Janz, S.; Bogdanov, A.; Picard, M.; Post, E.; Chow-Chong, P.; Malloy, M.; Roth, D.; Marshall, P.; Liu, K.Y.; Syrett, B. [Department of Electronics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); Institute for Microstructural Sciences, National Research Council Canada, Ottawa, Ontario K1A 0R6 (Canada); Department of Electronics, Carleton University, Ottawa, Ontario KIS 5B6 (Canada)
Plasma Wakefield Acceleration and FACET - Facilities for Accelerator Science and Experimental Test Beams at SLAC
Plasma wakefield acceleration is one of the most promising approaches to advancing accelerator technology. This approach offers a potential 1,000-fold or more increase in acceleration over a given distance, compared to existing accelerators. FACET, enabled by the Recovery Act funds, will study plasma acceleration, using short, intense pulses of electrons and positrons. In this lecture, the physics of plasma acceleration and features of FACET will be presented.
Andrei Seryi
Psychometric properties of the Dutch Five Facet Mindfulness Questionnaire (FFMQ) in patients with fibromyalgia
Mindfulness-based interventions are increasingly being used in clinical populations to reduce psychological distress and improve\\u000a functioning. The Five Facet Mindfulness Questionnaire (FFMQ) is a questionnaire that measures five facets of mindfulness:\\u000a observe, describe, actaware, nonjudge and nonreact. The goal of this study was to examine the psychometric properties of the\\u000a FFMQ in a clinical population of fibromyalgia patients. A total
Martine M. Veehof; Peter M. ten Klooster; Erik Taal; Gerben J. Westerhof; Ernst T. Bohlmeijer
Branched au nanostructures enriched with a uniform facet: facile synthesis and catalytic performances.
Well-defined noble metal nanocrystals (NMNCs) of a unique morphology yet a uniform facet have attracted broad interests. In this regard, those with a highly branched architecture have gained particular attention. Most of the currently existing branched NMNCs, however, are enclosed by mixed facets. We now report that branched Au nanoarchitectures could be facilely fabricated by mixing an aqueous solution of KAuCl4, an aqueous dispersion of graphene oxide, and ethanol under ambient conditions. Interestingly, unilike the conventional branched NMNCs, our unique Au nanostructures are predominately enriched with a uniform facet of {111}. Compared to the spherical Au nanostructures exposed with mixed facets, our branched nanospecies of a uniform facet display superior catalytic performances both for the catalytic reduction of 4-nitrophenol and the electrocatalytic oxidation of methanol. Our investigation represents the first example that Au nanostructures simultaneously featured with a highly branched architecture and a uniform crystal facet could be formulated. Our unique Au nanostructures provide a fundamental yet new scientific forum to disclose the correlation between the surface atomic arrangement and the catalytic performances of branched NMNCs. PMID:24918973
Zhu, Mingshan; Lei, Bin; Ren, Fangfang; Chen, Penglei; Shen, Yunfan; Guan, Bo; Du, Yukou; Li, Tiesheng; Liu, Minghua
Branched Au Nanostructures Enriched with a Uniform Facet: Facile Synthesis and Catalytic Performances
Welldefined noble metal nanocrystals (NMNCs) of a unique morphology yet a uniform facet have attracted broad interests. In this regard, those with a highly branched architecture have gained particular attention. Most of the currently existing branched NMNCs, however, are enclosed by mixed facets. We now report that branched Au nanoarchitectures could be facilely fabricated by mixing an aqueous solution of KAuCl4, an aqueous dispersion of graphene oxide, and ethanol under ambient conditions. Interestingly, unilike the conventional branched NMNCs, our unique Au nanostructures are predominately enriched with a uniform facet of {111}. Compared to the spherical Au nanostructures exposed with mixed facets, our branched nanospecies of a uniform facet display superior catalytic performances both for the catalytic reduction of 4nitrophenol and the electrocatalytic oxidation of methanol. Our investigation represents the first example that Au nanostructures simultaneously featured with a highly branched architecture and a uniform crystal facet could be formulated. Our unique Au nanostructures provide a fundamental yet new scientific forum to disclose the correlation between the surface atomic arrangement and the catalytic performances of branched NMNCs.
Zhu, Mingshan; Lei, Bin; Ren, Fangfang; Chen, Penglei; Shen, Yunfan; Guan, Bo; Du, Yukou; Li, Tiesheng; Liu, Minghua
A Systems Biology Approach to Synovial Joint Lubrication in Health, Injury, and Disease
The synovial joint contains synovial fluid (SF) within a cavity bounded by articular cartilage and synovium. SF is a viscous fluid that has lubrication, metabolic, and regulatory functions within synovial joints. SF contains lubricant molecules, including proteoglycan-4 and hyaluronan. SF is an ultrafiltrate of plasma with secreted contributions from cell populations lining and within the synovial joint space, including chondrocytes and synoviocytes. Maintenance of normal SF lubricant composition and function are important for joint homeostasis. In osteoarthritis, rheumatoid arthritis, and joint injury, changes in lubricant composition and function accompany alterations in the cytokine and growth factor environment and increased fluid and molecular transport through joint tissues. Thus, understanding the synovial joint lubrication system requires a multi-faceted study of the various parts of the synovial joint and their interactions. Systems biology approaches at multiple scales are being used to describe the molecular, cellular, and tissue components and their interactions that comprise the functioning synovial joint. Analyses of the transcriptome and proteome of SF, cartilage, and synovium suggest that particular molecules and pathways play important roles in joint homeostasis and disease. Such information may be integrated with physicochemical tissue descriptions to construct integrative models of the synovial joint that ultimately may explain maintenance of health, recovery from injury, or development and progression of arthritis.
Hui, Alexander Y.; McCarty, William J.; Masuda, Koichi; Firestein, Gary S.; Sah, Robert L.
ITER Central Solenoid uses butt joints for connecting the pancakes in the CS module. The principles of the butt joining of the CICC were developed by the JAPT during CSMC project. The difference between the CSMC butt joint and the CS butt joint is that the CS butt joint is an in-line joint, while the CSMC is a double joint through a hairpin jumper. The CS butt joint has to carry the hoop load. The straight length of the joint is only 320 mm, and the vacuum chamber around the joint has to have a split in the clamp shell. These requirements are challenging. Fig.1 presents a CSMC joint, and Fig.2 shows a CS butt joint. The butt joint procedure was verified and demonstrated. The tool is capable of achieving all specified parameters. The vacuum in the end was a little higher than the target, which is not critical and readily correctable. We consider, tentatively that the procedure is established. Unexpectedly, we discover significant temperature nonuniformity in the joint cross section, which is not formally a violation of the specs, but is a point of concern. All testing parameters are recorded for QA purposes. We plan to modify the butt joining tool to improve its convenience of operation and provide all features necessary for production of butt joints by qualified personnel.
Martovetsky, N N
NASA Technical Reports Server (NTRS)
A measurement system for simultaneously measuring torque and angular flexure in a pressure suit joint is described. One end of a joint under test is held rigid. A torque transducer is pivotably supported on the other movable end of a joint. A potentiometer is attached to the transducer by an arm. The wiper shaft of the potentiometer is gripped by a reference arm that rotates the wiper shaft the same angle as the flexure of joint. A signal is generated by the potentiometer which is representative of the joint flexure. A compensation circuit converts the output of the transducer to a signal representative of joint torque.
Vykukal, H. C.; Webbon, B. W. (inventors)
Jointness A Selected Bibliography.
National Technical Information Service (NTIS)
To assist researchers in a better understanding of how the United States armed services work together, the U.S. Army War College Library presents Jointness: A Selected Bibliography. A revised and updated version of our earlier bibliographies on jointness,...
Large displacement spherical joint
A new class of spherical joints has a very large accessible full cone angle, a property which is beneficial for a wide range of applications. Despite the large cone angles, these joints move freely without singularities.
Bieg, Lothar F. (Albuquerque, NM); Benavides, Gilbert L. (Albuquerque, NM)
National Technical Information Service (NTIS)
The report contains an explanation of anatomical concepts of joints and movements necessary in biomedical and physical therapy education. Upon completion of pamphlet, reader will be able to: (1) identify movements at any joint in the human body, (2) diffe...
P. Jacoby-Lockhart H. B. Slotnick
Immunohistochemical Evaluation of Neuroreceptors in Healthy and Pathological Temporo-Mandibular Joint
Aim: A study was performed on the articular disk and periarticular tissues of the temporo-mandibular joint (TMJ) with immunohistochemical techniques to give evidence to the presence of neuroreceptors (NRec) in these sites. Methods: The study was carried out on tissue samples obtained from 10 subjects without TMJ disease and from 7 patients with severe TMJ arthritis and arthrosis. We use antibodies directed against following antigens: Gliofibrillary Acidic Protein (GFAP), Leu-7, Myelin Basic Protein (MBP), Neurofilaments 68 kD (NF), Neuron Specific Enolase (NSE), S-100 protein (S-100) and Synaptophysin (SYN). Results: This study revealed that Ruffini's-like, Pacini's-like and Golgi's-like receptors can be demonstrated in TMJ periarticular tissues and that free nervous endings are present in the subsynovial tissues but not within the articular disk. We observed elongated cytoplamic processes of chondrocytes that demonstrated strong S-100 immunoreactivity but they were unreactive with all other antibodies. These cytoplamic processes were more abundant and thicker in the samples obtained from patients with disease TMJ. Conclusion: The results of this study confirm that different Nrec are detectable in TMJ periarticular tissues but they are absent within the articular disk. In the latter site, only condrocytic processes are evident, especially in diseased TMJ, and they might have been confused with nervous endings in previous morphological studies. Nevertheless the absence of immunoreactivity for NF, NSE and SYN proves that they are not of neural origin.
Favia, Gianfranco; Corsalini, Massimo; Di Venere, Daniela; Pettini, Francesco; Favia, Giorgio; Capodiferro, Saverio; Maiorano, Eugenio
Laser scattering properties of the rough ellipsoidal object with the random facet model
NASA Astrophysics Data System (ADS)
Laser scattering properties are studied from the rough surface of an ellipsoidal object with the random facet model and the electromagnetic scattering theory. For actual ellipsoidal objects, such as some airships and air balloons, their lateral correlation lengths are usually longer than the incident laser wavelength 1.06?m, and their surfaces are conventionally the Lambertian surface. Hence, it is feasible to analyze their laser scattering properties of the ellipsoidal object by means of the random facet model. In order to evaluate the scattering, firstly, the ellipsoidal surface is decomposed into many facets according to axial symmetry, then scattered intensity can be denoted for every facet with a laser scattering model of the Lambertian surface. Secondly, total intensity received by a far-field optical detective system is gained with the incoherent superposition principle for all facets, where an incident shadow function and a scattering shadow function are introduced. In the end, far-field angular distribution of the laser scattering intensity is computed and analyzed under different conditions. The numerical results suggest that the laser backscattering intensity of the ellipsoidal object increases with its surface roughness. However, if the ellipsoidal surface is correspondingly rough, the incident laser power might be scattered around.
Guo, Jing; Yang, Chun-Ping; Kang, Mei-Ling; Zhang, Yan; Wu, Jian
Differential Relations of Depression and Social Anxiety Symptoms to the Facets of Extraversion/Positive Emotionality
Previous research has shown that depression and social anxietytwo facets of internalizing psychopathology both are characterized by low levels of extraversion/positive emotionality (E/PE). However, little is known about the relations of the facets of E/PE with symptoms of depression and social anxiety. This study utilized multiple measures of each facet of E/PE, as well as depression and social anxiety symptoms. Self-report data were collected from large samples of college students and psychiatric outpatients. Separate factor analyses in each sample revealed a four-factor structure of E/PE, consisting of Sociability, Positive Emotionality, Ascendance, and Fun-Seeking. Structural equation modeling revealed that, after controlling for the higher-order internalizing factor and the overlap among the E/PE facets, social anxiety was broadly related to all four facets of E/PE, whereas depression was strongly related only to low positive emotionality. Implications for hierarchical models of personality and psychopathology, assessment and treatment, and etiological models are discussed.
Naragon-Gainey, Kristin; Watson, David; Markon, Kristian E.
Defeaturing CAD models using a geometry-based size field and facet-based reduction operators.
We propose a method to automatically defeature a CAD model by detecting irrelevant features using a geometry-based size field and a method to remove the irrelevant features via facet-based operations on a discrete representation. A discrete B-Rep model is first created by obtaining a faceted representation of the CAD entities. The candidate facet entities are then marked for reduction by using a geometry-based size field. This is accomplished by estimating local mesh sizes based on geometric criteria. If the field value at a facet entity goes below a user specified threshold value then it is identified as an irrelevant feature and is marked for reduction. The reduction of marked facet entities is primarily performed using an edge collapse operator. Care is taken to retain a valid geometry and topology of the discrete model throughout the procedure. The original model is not altered as the defeaturing is performed on a separate discrete model. Associativity between the entities of the discrete model and that of original CAD model is maintained in order to decode the attributes and boundary conditions applied on the original CAD entities onto the mesh via the entities of the discrete model. Example models are presented to illustrate the effectiveness of the proposed approach.
Quadros, William Roshan; Owen, Steven James
Neurologically Intact Patient Following Bilateral Facet Dislocation: Case Report and Review of Literature
Background Complete spinal cord lesions and quadriplegia occur in 50%-84% of patients with bilateral facet dislocation. We present a patient who suffered both bilateral facet dislocation and bilateral pedicle fractures while remaining neurologically intact. Based on this case and our literature review, we hypothesize that bilateral facet dislocations without neurological deficits are accompanied by significant associated fractures that facilitate the maintenance of cervical spine canal patency. Case Report After a fall down a flight of stairs, an 86-year-old woman presented to the hospital complaining of neck pain. She denied numbness and weakness of her extremities. On physical examination she was neurologically intact without focal sensory or motor deficits and with normal reflexes throughout. Computed tomography (CT) of her neck demonstrated bilateral C5-C6 facet dislocation with locking of the C6 superior articular process dorsal to the C5 inferior articular process, as well as corresponding bilateral C6 pedicle fractures. Additional acute fractures were identified on the thoracic CT. Magnetic resonance imaging demonstrated no spinal cord compression, edema, or hemorrhage. The patient had a C6-C7 anterior cervical discectomy and allograft fusion and a C5-T1 anterior cervical plate with screw fixation. Conclusion Because bilateral facet dislocations without neurological deficits are rare, the most appropriate surgical intervention is not evident. We believe the best choice as a first step is an anterior cervical discectomy and allograft fusion with plating.
Chakravarthy, Vikram; Mullin, Jeffrey P.; Abbott, E. Emily; Anderson, James; Benzel, Edward C.
Systematic review of tests to identify the disc, SIJ or facet joint as the source of low back pain
Clinical practice guidelines state that the tissue source of low back pain cannot be specified in the majority of patients.\\u000a However, there has been no systematic review of the accuracy of diagnostic tests used to identify the source of low back pain.\\u000a The aim of this systematic review was therefore to determine the diagnostic accuracy of tests available to clinicians
M. J. Hancock; C. G. Maher; J. Latimer; M. F. Spindler; J. H. McAuley; M. Laslett; N. Bogduk
Biomechanical analysis of the lumbar spine on facet joint force and intradiscal pressure - a finite element study
BACKGROUND: Finite element analysis results will show significant differences if the model used is performed under various material properties, geometries, loading modes or other conditions. This study adopted an FE model, taking into account the possible asymmetry inherently existing in the spine with respect to the sagittal plane, with a more geometrically realistic outline to analyze and compare the biomechanical
Ching-Sung Kuo; Hsuan-Teh Hu; Ruey-Mo Lin; Kuo-Yuan Huang; Po-Chun Lin; Zheng-Cheng Zhong; Mu-Lin Hseih
Asymmetric anatase TiO? nanocrystals with exposed high-index facets and their excellent lithium storage properties.
In this work, we demonstrate a unique organic solvent system to synthesize asymmetric anatase TiO(2) nanocrystals with a bipyramidal structure, where the upper pyramid is bound by (201) facets, and the lower pyramid is bound by (401) surfaces. Due to the high surface energy of these (401) high-index facets, the nanocrystals tend to assemble on these facets to minimize the free energy, leading to the formation of a dandelion-like hierarchical structure. PMID:21892504
Wu, Hao Bin; Chen, Jun Song; Lou, Xiong Wen David; Hng, Huey Hoon
Which facets of mindfulness are related to problematic eating among patients seeking bariatric surgery?
There has been growing research indicating the potential positive benefits of mindfulness-based interventions for obesity, but few studies have examined the relationship of mindfulness processes to obesity-related behaviors, particularly among clinical populations such as bariatric surgery candidates. The current study examined the relationship of specific mindfulness facets to a variety of problematic eating behaviors assessed through diagnostic interviews in a clinical sample of 820 patients seeking bariatric surgery. Results indicated that greater mindfulness on specific facets, particularly acting with awareness, was related to less binge and emotional eating. Greater mindfulness was also related, though less consistently, to less habitual overeating and grazing. The observing facet was generally unrelated to problematic eating, but in a few cases being more observant related to having greater eating problems. The results of the study and future directions are discussed in relation to research on problematic eating in obesity and mindfulness-based interventions. PMID:24854822
Levin, Michael E; Dalrymple, Kristy; Himes, Susan; Zimmerman, Mark
Rotary encoding device using polygonal mirror with diffraction gratings on each facet
NASA Technical Reports Server (NTRS)
A device for position encoding of a rotating shaft in which a polygonal mirror having a number of facets is mounted to the shaft and a monochromatic light beam is directed towards the facets. The facets of the polygonal mirror each have a low line density diffraction grating to diffract the monochromatic light beam into a number of diffracted light beams such that a number of light spots are created on a linear array detector. An analog-to-digital converter is connected to the linear array detector for reading the position of the spots on the linear array detector means. A microprocessor with memory is connected to the analog-to-digital converter to hold and manipulate the data provided by the analog-to-digital converter on the position of the spots and to compute the position of the shaft based upon the data from the analog-to-digital converter.
Leviton, Douglas B. (inventor)
Molecular ordering and adsorbate induced faceting in the Ag{110}-(S)-glutamic acid system.
The adsorption of the amino acid, (S)-glutamic acid, was investigated on Ag{110} as a function of coverage and adsorption temperature using the techniques of scanning tunneling microscopy, low energy electron diffraction, and reflection absorption infrared spectroscopy. In the monolayer, (S)-glutamic acid was found to adsorb predominantly in the anionic glutamate form. Several discrete ordered adlayer structures were observed depending on preparation conditions. In addition, (S)-glutamic acid was found to induce both one- and two-dimensional faceting of the Ag{110} surface. In some cases, evidence was found that the 2-D faceting involved the creation of a chiral facet distribution. A comparison is made of the Ag/(S)-glutamic acid system with analogous studies of amino acids on Cu. PMID:16207023
Jones, T E; Baddeley, C J; Gerbi, A; Savio, L; Rocca, M; Vattuone, L
Linear-phase approximation in the triangular facet near-field physical optics computer program
NASA Technical Reports Server (NTRS)
Analyses of reflector antenna surfaces use a computer program based on a discrete approximation of the radiation integral. The calculation replaces the actual surface with a triangular facet representation; the physical optics current is assumed to be constant over each facet. Described here is a method of calculation using linear-phase approximation of the surface currents of parabolas, ellipses, and shaped subreflectors and compares results with a previous program that used a constant-phase approximation of the triangular facets. The results show that the linear-phase approximation is a significant improvement over the constant-phase approximation, and enables computation of 100 to 1,000 lambda reflectors within a reasonable time on a Cray computer.
Imbriale, W. A.; Hodges, R. E.
Mesoporous NiO crystals with dominantly exposed {110} reactive facets for ultrafast lithium storage
NASA Astrophysics Data System (ADS)
Faceted crystals with exposed highly reactive planes have attracted intensive investigations for applications such as hydrogen production, enhanced catalytic activity, and electrochemical energy storage and conversion. Herein, we report the synthesis of mesoporous NiO crystals with dominantly exposed {110} reactive facets by the thermal conversion of hexagonal Ni(OH)2 nanoplatelets. When applied as anode materials in lithium-ion batteries, mesoporous NiO crystals exhibit a high reversible lithium storage capacity of 700 mAh g-1 at 1 C rate in 100 cycles and an excellent cyclability. In particular, the dominantly exposed {110} reactive facets and mesoporous nanostructure of NiO crystals lead to ultrafast lithium storage, which mimics the high power delivery of supercapacitors.
Su, Dawei; Ford, Mike; Wang, Guoxiu
Mindfulness, health symptoms and healthcare utilization: Active facets and possible affective mediators.
Prior work has linked mindfulness with superior physical and psychological health outcomes. However, studies to date have infrequently tested the unique contributions of individual mindfulness facets, inadequately tested links between facets and healthcare utilization, and have not tested whether depression or anxiety may influence these links. In the current report, 40 young, middle aged and older adults (N?=?121) completed measures of dispositional mindfulness, health, healthcare utilization and depression/anxiety. As expected, global trait mindfulness did not predict outcomes while individual mindfulness facets predicted both objective and subjective health as well as healthcare utilization. Across models, observe scores - the tendency to attend to thoughts, sensations and feelings - predicted poorer, and non-reactivity scores better, outcomes even when controlling for demographic and health confounds. Depressed and anxious emotion reduced some but not all mindfulness-health links. Results are discussed in terms of the mechanisms by which greater mindfulness may facilitate better health and health behaviour. PMID:23909611
Consedine, Nathan S; Butler, Haley F
Method and a carrier for treating end facets in photonic devices
US Patent & Trademark Office Database
A carrier for treating photonic devices such as laser bars is provided with a recessed formation with a web surface for supporting the photonic device in contact therewith as well as at least one side surface forming an abutment surface for engaging a respective end facet of the photonic device. The photonic device is arranged in the recessed formation so that the lower surface of the photonic device is masked with respect to the treatment source, while at least one end facet of the photonic device engages at least one side surface by leaving exposed a surface to be treated. A protection member is placed in contact with the upper surface of the photonic device and the carrier with the photonic device arranged therein is exposed to the treatment source. The treatment is thus effective substantially exclusively on the surfaces of the end facets to be treated.
Faceting and coarsening dynamics in the complex Swift-Hohenberg equation.
The complex Swift-Hohenberg equation models pattern formation arising from an oscillatory instability with a finite wave number at onset and finds applications in lasers, optical parametric oscillators, and photorefractive oscillators. We show that with real coefficients this equation exhibits two classes of localized states: localized in amplitude only or localized in both amplitude and phase. The latter are associated with phase-winding states in which the real and imaginary parts of the order parameter oscillate periodically but with a constant phase difference between them. The localized states take the form of defects connecting phase-winding states with equal and opposite phase lag, and can be stable over a wide range of parameters. The formation of these defects leads to faceting of states with initially spatially uniform phase. Depending on parameters these facets may either coarsen indefinitely, as described by a Cahn-Hilliard equation, or the coarsening ceases leading to a frozen faceted structure. PMID:19905429
Gelens, Lendert; Knobloch, Edgar
Faceting of {sigma}3 and {sigma}9 grain boundaries in Cu-Bi alloys
The faceting of {sigma}3 and {sigma}9 tilt grain boundaries (GBs) has been studied in bicrystals of pure Cu and Cu-Bi alloys containing 2.5 x 10{sup -3}, 10 x 10{sup -3} and 16 x 10{sup -3} at.% Bi. The {sigma}3(1 0 0), {sigma}9(1 0 0), {sigma}9(-1 1 0), and {sigma}9(-1 2 0) facets and non-CSL {sigma}3 82 deg 9R facet were observed, where {sigma} is the inverse density of coincidence sites. The ratio between GB energy, {sigma}{sub GB}, and surface energy, {sigma}{sub sur}, was measured by atomic force microscopy using the GB thermal-groove method. The GB energy and thermal-groove deepening rate increased slightly between 0 and 10 x 10{sup -3} at.% Bi for all facets studied. However, between 10 x 10{sup -3} and 16 x 10{sup -3} at.% Bi the GB energy increased dramatically [from a factor 2 for the {sigma}9(1 1 0) facet to 15 times larger for the {sigma}3(1 0 0) facet]. The thermal-groove deepening rate also increased by a factor of 10 in this concentration range. This change corresponds well with the GB solidus line (i.e., the formation of a stable layer of a liquid-like GB phase called GB prewetting) observed previously. Wulff diagrams were constructed using measured {sigma}{sub GB}/{sigma}{sub sur} values.
Straumal, B.B. [Laboratory of Interfaces in Metals, Institute of Solid State Physics, Institutskii prospect 15, 142432 Chernogolovka, Moscow District (Russian Federation)]. E-mail: email@example.com; Polyakov, S.A. [Laboratory of Interfaces in Metals, Institute of Solid State Physics, Institutskii prospect 15, 142432 Chernogolovka, Moscow District (Russian Federation); Max-Planck-Institut fuer Metallforschung and Institut fuer Metallkunde, Heisenbergstr. 3, 70569 Stuttgart (Germany); Bischoff, E. [Max-Planck-Institut fuer Metallforschung and Institut fuer Metallkunde, Heisenbergstr. 3, 70569 Stuttgart (Germany); Gust, W. [Max-Planck-Institut fuer Metallforschung and Institut fuer Metallkunde, Heisenbergstr. 3, 70569 Stuttgart (Germany); Baretzky, B. [Max-Planck-Institut fuer Metallforschung and Institut fuer Metallkunde, Heisenbergstr. 3, 70569 Stuttgart (Germany)
The Unique Relations between Emotional Awareness and Facets of Affective Instability
The relation between affective instability and two facets of emotional awareness, attention to emotion and clarity of emotion, was examined in two community samples (Ns = 303, 101) and one student sample (N=409). Affective instability was positively associated with attention to emotion and negatively associated with clarity of emotion. The two facets of affective instability, affect intensity and emotional variability, were differentially associated with the two components of emotional awareness. As hypothesized, affect intensity was uniquely associated with attention to emotion, whereas emotional variability was uniquely (inversely) associated with clarity of emotion even after taking into account shared variance with neuroticism and gender.
Thompson, Renee J.; Dizen, Muge; Berenbaum, Howard
Explaining global job satisfaction by facets of job satisfaction: the Japanese civil servants study
Objectives Management of job satisfaction is of growing importance in terms of the maintenance of employees health. This study aimed\\u000a to evaluate which and to what extent facets of job satisfaction contributed to global job satisfaction.\\u000a \\u000a \\u000a \\u000a \\u000a Methods The participants were 4286 employees aged 1869 years working in local government in Japan. A questionnaire survey was conducted\\u000a in 19981999. Seven facets of job
Takashi Tatsuse; Michikazu Sekine
Equilibrium faceting formation in vicinal Al2O3 (0001) surface caused by annealing
NASA Astrophysics Data System (ADS)
We report on a heat-induced transformation of the surface of ?-alumina (0001) crystals which have an off-cut in the [12₤10] direction. Annealing the crystal causes the surface to transform into a regular array of (0001) and (12₤16) facets. The resultant faceted morphology represents the equilibrium state of the system. It is demonstrated that the average terrace periodicity is determined by the annealing temperature. Possible causes for the surface rearrangement are also discussed. This method could be used for producing templates with controlled periodicity for growth of nanostructure arrays.
Verre, R.; Sofin, R. G. S.; Usov, V.; Fleischer, K.; Fox, D.; Behan, G.; Zhang, H.; Shvets, I. V.
Gradual facet degradation of (Al,In)GaN quantum well lasers
NASA Astrophysics Data System (ADS)
In our study, III-nitride laser diodes with uncoated facets obtained by cleavage show a much faster degradation than coated ones. An increase in threshold current and drop of slope efficiency suggest increased absorption losses. Degradation experiments in different atmospheres prove the influence of the respective atmosphere and indicate the growth of an oxide film leading to increased absorption. Because the observed degradation is insensitive to the photon density we suggest nonradiative centers, which are saturated at low photon densities, to be at the origin of degradation. No evidence for photon enhanced degradation of coated laser diodes was found. A dielectric coating efficiently protects the facets.
K■mmler, V.; Lell, A.; Hðrle, V.; Schwarz, U. T.; Schoedl, T.; Wegscheider, W.
Soils and geomorphic evolution of bedrock facets on a tectonically active mountain front, western Sangre de Cristo Mountains, New Mexico
NASA Astrophysics Data System (ADS)
Soil profiles, colluvial stratigraphy, and detailed hillslope morphology are key elements used for geomorphic interpretations of the form and long-term evolution of triangular facets on a 1200 m high, tectonically active mountain front. The facets are developed on Precambrian gneisses and Tertiary volcanic and plutonic rocks along a complexly segmented, active normal-fault zone in the Rio Grande rift of northern New Mexico. The detailed morphologies of 20- to 350 m high facets are defined by statistical and time-series analyses of 40 field transects that were keyed to observations of colluvium, bedrock, microtopography, and vegetation. The undissected parts of most facets are transport-limited hillslopes mantled with varying thicknesses (0.1 to > 1 m thick) of sand and gravel colluvium between generally sparse (?10-30%) bedrock outcrops. Facet soils range from (a) thin (? 0.2 m) weakly developed soils with cumulic silty A or transitional A/B epipedons above Cox horizons in bedrock or colluvium, to (b) deep (?0.5-1 m) moderately to strongly developed profiles containing thick cambic (Bw) and/or argillic (Bt) horizons that commonly extend into highly weathered saprolitic bedrock. The presence of strongly weathered profiles and thick colluvium suggests that rates of colluvial transport and hillslope erosion are less than or equal to rates of soil development over at least a large part of the Holocene. The catenary variation of soils and colluvium on selected facet transects indicate that the degree of soil development generally increases and the thickness of colluvium decreases upslope on most facets. This overall pattern is commonly disrupted on large facet hillslopes by irregular secondary soil variations linked to intermediate-scale (20-60 + m long) concave slope elements. These features are interpreted to reflect discontinuous transport and erosion of colluvium down-slope below bedrock outcrops. The degree of weathering in subsurface bedrock commonly increases more systematically upslope on most facets than colluvial soils. This pattern is consistent with an increase in age with height on these fault-generated facet hillslopes. The characteristic range of internal variation in soils and colluvial deposits on a given facet also varies greatly among facets with differing overall morphologies and external environments. Deep cumulic soils and thick colluvium occur consistently on steep (? 30¯), high, and relatively undissected facets above the narrow central sections of fault segments. Much thinner and less weathered colluvium and soils overlie saprolitic bedrock at shallow depths on low, highly dissected, gently sloping (? 20¯) facets above complex fault segment boundaries. Parametric and nonparametric analyses of variance indicate that these large-scale contrasts in facet morphology correlate primarily with a few facet subgroups related, in decreasing importance, to variations in range-front faulting, bedrock lithology, and piedmont dissection or aggradation. These factors are related to facet morphology, drainage evolution, and hillslope-soil stratigraphy in a general geomorphic model for fault-generated facets. In this model, segmentation-related changes in the geometry and/or rates of faulting most strongly affect facet size, slope gradient, the thickness of colluvium and soil development, and drainage patterns. Facets of varying heights have similar hillslope forms at the same position on the range front; these characteristic morphologies are established under prevailing tectonic and nontectonic conditions on facets as bedrock is initially exposed from beneath alluvial-covered fault scarps above a height threshold of 15-35 m.
Menges, Christopher M.
NASA Astrophysics Data System (ADS)
Unimorph active rigidity joints, constructed from Shape Memory Alloy and Shape Memory Polymer and capable of bending actuation, are reported in this work. An embedded aluminum shim was added to each joint as a structural element to facilitate actuation. Joints were actuated using ohmic Tri-Phase and pulse heating processes with different results. It appeared that openloop position control could be achieved using pulse heating. Actuator improvements and future experiments are proposed.
Geeng, Franklin; Manzo, Justin; Garcia, Ephrahim
Investigation of the facet-dependent performance of ?-Fe2O3 nanocrystals for heavy metal determination by stripping voltammetry.
We find for the first time that the electrochemical performances of the ?-Fe2O3 nanostructures depend on their exposed facets. Density functional theory calculations are carried out to better and scientifically understand the effect of different exposed facets at the atomic-scale level. PMID:24710198
Xu, Wei-Hong; Meng, Qiang-Qiang; Gao, Chao; Wang, Jing; Li, Qun-Xiang; Liu, Jin-Huai; Huang, Xing-Jiu
Catalytic CO oxidation on nanoscale Pt facets: Effect of interfacet CO diffusion on bifurcation and fluctuation behavior
NASA Astrophysics Data System (ADS)
We present lattice-gas modeling of the steady-state behavior in CO oxidation on the facets of nanoscale metal clusters, with coupling via interfacet CO diffusion. The model incorporates the key aspects of the reaction process, such as rapid CO mobility within each facet and strong nearest-neighbor repulsion between adsorbed O. The former justifies our use of a ``hybrid'' simulation approach treating the CO coverage as a mean-field parameter. For an isolated facet, there is one bistable region where the system can exist in either a reactive state (with high oxygen coverage) or a (nearly CO-poisoned) inactive state. Diffusion between two facets is shown to induce complex multistability in the steady states of the system. The bifurcation diagram exhibits two regions with bistabilities due to the difference between adsorption properties of the facets. We explore the role of enhanced fluctuations in the proximity of a cusp bifurcation point associated with one facet in producing transitions between stable states on that facet, as well as their influence on fluctuations on the other facet. The results are expected to shed more light on the reaction kinetics for supported catalysts.
Pavlenko, N.; Evans, J. W.; Liu, Da-Jiang; Imbihl, R.
Catalytic CO oxidation on nanoscale Pt facets: effect of interfacet CO diffusion on bifurcation and fluctuation behavior.
We present lattice-gas modeling of the steady-state behavior in CO oxidation on the facets of nanoscale metal clusters, with coupling via interfacet CO diffusion. The model incorporates the key aspects of the reaction process, such as rapid CO mobility within each facet and strong nearest-neighbor repulsion between adsorbed O. The former justifies our use of a "hybrid" simulation approach treating the CO coverage as a mean-field parameter. For an isolated facet, there is one bistable region where the system can exist in either a reactive state (with high oxygen coverage) or a (nearly CO-poisoned) inactive state. Diffusion between two facets is shown to induce complex multistability in the steady states of the system. The bifurcation diagram exhibits two regions with bistabilities due to the difference between adsorption properties of the facets. We explore the role of enhanced fluctuations in the proximity of a cusp bifurcation point associated with one facet in producing transitions between stable states on that facet, as well as their influence on fluctuations on the other facet. The results are expected to shed more light on the reaction kinetics for supported catalysts. PMID:11800750
Pavlenko, N; Evans, J W; Liu, Da-Jiang; Imbihl, R
Venice unfolding: a tangible user interface for exploring faceted data in a geographical context
We introduce Venice Unfolding, a case study on tangible geo-visualization on an interactive tabletop to enable the exploration of architectural projects in Venice. Our tangible user interface consists of a large display showing projects on a map, and a polyhedral object to browse these data interactively by selecting and filtering various metadata facets. In this paper we describe a prototype
Till Nagel; Frank Heidmann; Massimiliano Condotta; Erik Duval
Concave trisoctahedral Ag3PO4 microcrystals with high-index facets and enhanced photocatalytic properties.
Herein, we demonstrate for the first time the fabrication of concave trisoctahedral Ag(3)PO(4) microcrystals enclosed by {221} and {332} facets based on the heteroepitaxial growth procedure, which exhibit much higher photocatalytic activities than cubic Ag(3)PO(4) and commercial N-doped TiO(2). PMID:23223196
Jiao, Zhengbo; Zhang, Yan; Yu, Hongchao; Lu, Gongxuan; Ye, Jinhua; Bi, Yingpu
Low Delta-K Faceted Crack Growth in Titanium Alloys (Postprint).
National Technical Information Service (NTIS)
This communication describes the results of spectrum fatigue loading experiments conducted on cast+HIT Ti-6Al-4V. the purpose of the experiments is to elucidate the nature of the faceted crack growth that occurs at low values of delta-K in titanium alloys...
A. Bhattacharjee A. H. Rosenberger A. L. Pilchak J. C. Williams
The Two Facets of Collaboration: Cooperation and Coordination in Strategic Alliances
This paper unpacks two underspecified facets of collaboration: cooperation and coordination. Prior research has emphasized cooperation, specifically partners' commitment and alignment of interests, as the key determinant of collaborative success. Scholars have paid less attention to the critical role of coordinationthe effective alignment and adjustment of partners' actions. To redress this imbalance, we conceptually disentangle cooperation and coordination in the
Ranjay Gulati; Franz Wohlgezogen; Pavel Zhelyazkov
Crystal facet dependence of water oxidation on BiVO4 sheets under visible light irradiation.
Monoclinic BiVO(4) crystals with preferentially exposed (040) facets were hydrothermally synthesized by using a trace amount of TiCl(3) as the directing agent; this function was confirmed by X-ray diffraction patterns (XRD) and high-resolution transmission electron microscopy (HRTEM). The effects of the directing agent TiCl(3) and the pH values applied during synthesis have been studied, and the optimized BiVO(4) sample with highly exposed (040) facet could be obtained by using 1.2 at.% of TiCl(3) as the directing agent at a pH value of 2. Some complementary techniques were also applied to exclude the effects of the structural and physical property changes, such as surface area and hydrophilicity. The photocatalytic activity of oxygen evolution on BiVO(4) is found to be proportionally correlated with the exposed surfaces of the (040) facet. It is assumed that the active sites with a BiV(4) structure on the exposed (040) facet is assigned to be responsible for the high activity of O(2) evolution. PMID:21243695
Wang, Donge; Jiang, Hongfu; Zong, Xu; Xu, Qian; Ma, Yi; Li, Guoling; Li, Can
Treatment of bipolar disorder: a complex treatment for a multi-faceted disorder
BACKGROUND: Manic-depression or bipolar disorder (BD) is a multi-faceted illness with an inevitably complex treatment. METHODS: This article summarizes the current status of our knowledge and practice of its treatment. RESULTS: It is widely accepted that lithium is moderately useful during all phases of bipolar illness and it might possess a specific effectiveness on suicidal prevention. Both first and second
Konstantinos N Fountoulakis; Eduard Vieta; Melina Siamouli; Marc Valenti; Stamatia Magiria; Timucin Oral; David Fresno; Panteleimon Giannakopoulos; George S Kaprinis
Dynamics of partially faceted melt/crystal interfaces II: multiple step source calculations
NASA Astrophysics Data System (ADS)
Facets appearing on the liquid/solid interface, during directional crystal growth from the melt, advance via a combination of step-flow (i.e. linear) and step-source (i.e. non-linear) kinetics. In this manuscript we rigorously calculate a number of examples in which the macroscopic shape of the interface is dramatically affected by the type, distribution and dynamics of step sources along these facets. The new numerical algorithm employed, based on decoupling interface motion from thermal field calculations, is briefly described (further details are given elsewhere), after which several sets of results are presented. Specifically, an experimental observation of facet evolution dynamics during the melt growth of silicon, qualitatively explained in Voronkov and Pankov [Sov. Phys. Crystallogr. 20(6) (1975) 697] , is quantitatively analyzed and explained here. Additional calculations include analyses of dynamics associated with the hypothetical sudden appearance of a dislocation step-source on a previously dislocation-free advancing facet. Large rates of latent heat release associated with such abrupt changes between growth mechanisms are shown, in some cases, to promote melt-back of rough portions of the interface. Finally, select semi-analytical solutions to the interface motion equation, in non-trivial situations involving transitions between growth mechanisms, are shown to verify numerical calculations of the advancing interface.
Weinstein, Oleg; Brandon, Simon
FACET; Oil and gas production facilities cost-estimating and-control techniques
The merits of using commercially available software packages vs. in-house software and data bases are frequently assessed by cost engineers in consulting, contracting, and operating companies alike. There is no consensus on which approach is better; each company has individual requirements that are better met by one or another alternative. This paper describes FACET (facilities cost estimating techniques) programs and
C. W. Cole; I. J. Banszky
Polymer waveguide end facet roughness and optical input/output coupling loss for OPCB applications
NASA Astrophysics Data System (ADS)
Electro-optical printed circuit board technology (EOCB) based on integrated planar polymer optical waveguides has been the subject of research and development for many years to provide a cost viable, fully integrated system embedded optical interconnect solution, however a number of constraints of this technology have yet to be overcome. Optical coupling loss at the input and output of the waveguides is one of the major issues and waveguide end facet roughness is one of the main sources of the coupling loss which is investigated in this paper. The results of a comprehensive investigation of the end facet roughness of multimode polymer waveguides, fabricated on FR4 printed circuit boards, PCBs, and its effect of optical loss are presented theoretically and experimentally. The waveguide end facet roughness was measured using an atomic force microscope, AFM, when the waveguides were cut using a milling router with various numbers of cutting edges called flutes. The optimized cutting parameters are derived and the optical coupling loss, between the laser source and the waveguide, due to the different roughness magnitudes is measured by experiment for the first time. To improve the surface quality and decrease the waveguide optical loss, a new fabrication technique for reducing the end facet roughness after cutting is proposed and demonstrated. The insertion loss was reduced by 2.60 dB +/- 1.3 dB which is more than that achieved by other conventional methods such as index matching fluid.
Baghsiahi, Hadi; Wang, Kai; Pitwon, Richard; Selviah, David R.
Applying Perkins's Facets of a Learning Environment for Information Literacy Instruction
ERIC Educational Resources Information Center
Perkins, a professor of Education at Harvard University, promoted the use of constructivism in conjunction with information processing technologies to facilitate students' understanding and active use of knowledge and skills. He identified five facets of a learning environment including: information banks, symbol pads, construction kits,
Blummer, Barbara
A Complete Description of Cones and Polytopes Including Hypervolumes of All Facets of a Polytope
ERIC Educational Resources Information Center
In this paper methods and algorithms for identifying the main elements (edges and facets of any dimension) of a cone and a polytope, and calculating the corresponding hypervolumes are presented. The cones and polytopes are supposed to be given as the non-negative linear combination and the convex hull generated by a, not necessarily minimal, set
Jubete, F.; Castillo, E.
Perspectives on fluid and crystallized intelligence: facets for verbal, numerical, and figural intelligence
Fluid intelligence is often measured with figural tests, whereas crystallized intelligence is often assessed with verbal tests. It is argued that construct-irrelevant figural variance is included in fluid intelligence and construct-irrelevant verbal variance is included in crystallized intelligence. The specification of a content facet comprising verbal, numerical, and figural abilities for fluid and crystallized intelligence would reduce the construct irrelevant
AndrÕ Beauducel; Burkhard Brocke; Detlev Liepmann
The heritability of conscientiousness facets and their relationship to IQ and academic achievement
The heritability of conscientiousness has been one of the least explored of the NEO PI domains. Here we focus on the facet scales of the conscientiousness domain, estimating both their heritability and their correlations with measures of IQ and academic achievement (Queensland Core Skills Test; QCST) in a sample of adolescent twins and their non-twin siblings. Our findings confirmed positive
Michelle Luciano; Mark A. Wainwright; Margaret J. Wright; Nicholas G. Martin
Teachers' Perceptions Structured through Facet Theory: Smallest Space Analysis versus Factor Analysis.
ERIC Educational Resources Information Center
Examined the facet theory (FT) of L. Gutman and compared it to factor analysis (FA) in the context of two research studies, one of desirable student traits perceived by 203 Israeli teachers and the other of the perceptions of 92 Israeli teachers regarding teacher professionalism. By using FT and FA, the multidimensional theory and structural
Maslovaty, Nava; Marshall, Anne E.; Alkin, Marvin C.
FACET: A simulation software framework for modeling complex societal processes and interactions
FACET, the Framework for Addressing Cooperative Extended Transactions, was developed at Argonne National Laboratory to address the need for a simulation software architecture in the style of an agent-based approach, but with sufficient robustness, expressiveness, and flexibility to be able to deal with the levels of complexity seen in real-world social situations. FACET is an object-oriented software framework for building models of complex, cooperative behaviors of agents. It can be used to implement simulation models of societal processes such as the complex interplay of participating individuals and organizations engaged in multiple concurrent transactions in pursuit of their various goals. These transactions can be patterned on, for example, clinical guidelines and procedures, business practices, government and corporate policies, etc. FACET can also address other complex behaviors such as biological life cycles or manufacturing processes. To date, for example, FACET has been applied to such areas as land management, health care delivery, avian social behavior, and interactions between natural and social processes in ancient Mesopotamia.
Christiansen, J. H.
Facet Personality and Surface-Level Diversity as Team Mental Model Antecedents: Implications for Implicit Coordination
Team mental models (TMMs) have received much attention as important drivers of effective team processes and performance. Less is known about the factors that give rise to these shared cognitive structures. We examined potential antecedents of TMMs, with a specific focus on team composition variables, including various facets of personality and surface-level diversity. Further, we examined implicit coordination as an
David M. Fisher; Suzanne T. Bell; Erich C. Dierdorff; James A. Belohlav
Using Self-Report Assessment Methods to Explore Facets of Mindfulness
The authors examine the facet structure of mindfulness using five recently developed mindfulness questionnaires. Two large samples of undergraduate students completed mindfulness questionnaires and measures of other constructs. Psychometric properties of the mindfulness questionnaires were examined, including internal consistency and convergent and discriminant relationships with other variables. Factor analyses of the combined pool of items from the mindfulness questionnaires suggested
Ruth A. Baer; Gregory T. Smith; Jaclyn Hopkins; Jennifer Krietemeyer; Leslie Toney
Construct Validity of the Five Facet Mindfulness Questionnaire in Meditating and Nonmeditating Samples
Previous research on assessment of mindfulness by self-report suggests that it may include five component skills: observing, describing, acting with awareness, nonjudging of inner experience, and nonreactivity to inner experience. These elements of mindfulness can be measured with the Five Facet Mindfulness Questionnaire (FFMQ). The authors investigated several aspects of the construct validity of the FFMQ in experienced meditators and
Ruth A. Baer; Gregory T. Smith; Emily Lykins; Daniel Button; Jennifer Krietemeyer; Shannon Sauer; Erin Walsh; Danielle Duggan; J. Mark G. Williams
Using Self-Report Assessment Methods to Explore Facets of Mindfulness
ERIC Educational Resources Information Center
The authors examine the facet structure of mindfulness using five recently developed mindfulness questionnaires. Two large samples of undergraduate students completed mindfulness questionnaires and measures of other constructs. Psychometric properties of the mindfulness questionnaires were examined, including internal consistency and convergent
Baer, Ruth A.; Smith, Gregory T.; Hopkins, Jaclyn; Krietemeyer, Jennifer; Toney, Leslie
Mind Your Words: Positive and Negative Items Create Method Effects on the Five Facet Mindfulness Questionnaire
ERIC Educational Resources Information Center
Mindfulness, a construct that entails moment-to-moment effort to be aware of present experiences and positive attitudinal features, has become integrated into the sciences. The Five Facet Mindfulness Questionnaire (FFMQ), one popular measure of mindfulness, exhibits different responses to positively and negatively worded items in nonmeditating
Van Dam, Nicholas T.; Hobkirk, Andrea L.; Danoff-Burg, Sharon; Earleywine, Mitch
A Multi-Faceted Formative Assessment Approach: Better Recognising the Learning Needs of Students
ERIC Educational Resources Information Center
Students are increasingly subject to a series of learning pressures that prevent effective engagement in assessment. Thus, the aim of this study was to create a multi-faceted formative assessment approach that better enabled students to engage in the assessment process. A formative assessment approach, consisting of six key initiatives, is
Jenkins, James O.
Detection of faceted crystals in deep convective clouds via the antisolar peak
It is shown that an antisolar peak can clearly be detected in backscattered near-infrared reflectances from deep convective cloud tops. This peak should be caused only by regularly faceted ice crystals, primarily columns and plates, rather than rimed or irregular particles. Using 13 years of AVHRR (advanced very high resolution radiometer) data, the average peak stands 22% above the background
Steven C. Sherwood
An Examination of Blue- versus White-Collar Workers' Conceptualizations of Job Satisfaction Facets
ERIC Educational Resources Information Center
This study examined the degree to which blue- versus white-collar workers differentially conceptualize various job facets, namely the work itself, co-workers, supervisors, and pay. To examine these potential differences, we conducted a series of analyses on job satisfaction ratings from two samples of university workers. Consistent with the study
Hu, Xiaoxiao; Kaplan, Seth; Dalal, Reeshad S.
The role of shape on electronic structure and charge transport in faceted PbSe nanocrystals.
We have determined the effect of shape on the charge transport characteristics of nanocrystals. Our study looked at the explicit determination of the electronic properties of faceted nanocrystals that essentially probe the limit of current computational reach, i.e., nanocrystals from 1.53 to 2.1 nm in diameter. These nanocrystals, which resemble PbSe systems, are either bare or covered in short ligands. They also differ in shape, octahedral vs cube-octahedral, and in superlattice symmetry (fcc vs bcc). We have provided insights on electron and hole coupling along different facets and overall charge mobility in bcc and fcc superlattices. We have determined that the relative areas of (100) to (111) facets, and facet atom types are important factors governing the optimization of charge transport. The calculated electronic density of states shows no role of -SCH3- ligands on states near the band gap. Electron coupling between nanocrystals is significantly higher than that of hole coupling; thiol ligands lower the ratio between electron and hole couplings. Stronger coupling exists between smaller nanocrystals. PMID:24548107
Kaushik, Ananth P; Lukose, Binit; Clancy, Paulette
Which facets of mindfulness predict the presence of substance use disorders in an outpatient psychiatric sample?
There have been inconsistent findings regarding the relationship of mindfulness to substance use disorders, which may be attributable in part to measurement issues and the use of nonclinical samples. The current study examined the relationship between specific facets of mindfulness and substance use disorders (SUD) in a clinical sample. The sample consisted of 867 patients seeking outpatient treatment and who completed diagnostic interviews and self-report assessments. Results indicated that deficits in acting with awareness, being nonjudgmental, and nonreactivity were related to the presence of a current SUD relative to those with no history of SUD, although only acting with awareness and being nonjudgmental were related when all of the facets were included in a logistic regression. Patients with a past history of SUD had greater deficits in acting with awareness relative to those with no history of SUD. Results were similar when examining alcohol use and drug use disorders separately. Current nicotine users had greater deficits in being nonjudgmental, but not on other mindfulness facets. The observing facet was not related to current or past history of SUD. The results of the study and future directions are discussed in relation to research on mindfulness-based treatments for addiction. (PsycINFO Database Record (c) 2014 APA, all rights reserved). PMID:24274438
Levin, Michael E; Dalrymple, Kristy; Zimmerman, Mark
Facets of Impulsivity Are Differentially Linked to Insomnia: Evidence From an Exploratory Study
This study investigated the association between insomnia and four facets of impulsivity as distinguished by Whiteside and Lynam (2001): urgency, (lack of) premeditation, (lack of) perseverance, and sensation seeking. A sample of 233 university students completed the UPPS Impulsive Behavior Scale, the Insomnia Severity Index, and a short questionnaire on sleep-related mentation. Correlational analyses revealed that urgency was related to
Ralph E. Schmidt; Philippe Gay; Martial Van der Linden
Evaluating the Diagnostic Validity of a Facet-Based Formative Assessment System
ERIC Educational Resources Information Center
This paper describes methods for an alignment study and psychometric analyses of a formative assessment system, Diagnoser Tools for physics. Diagnoser Tools begin with facet clusters as the interpretive framework for designing questions and instructional activities. Thus each question in the diagnostic assessments includes distractors that
DeBarger, Angela Haydel; DiBello, Louis; Minstrell, Jim; Feng, Mingyu; Stout, William; Pellegrino, James; Haertel, Geneva; Harris, Christopher; Ructinger, Liliana
Near-surface faceted crystals, avalanches and climate in high-elevation, tropical mountains of Bolivia
The importance of near-surface faceted crystals in forming weak layers associated with snow avalanches has recently received greater attention. However, there is still much to be learned concerning the formation and growth of these crystal types, their geographical extent, and related avalanche activity. Here we report on two avalanches that occurred during late September 1999 at high-elevations in the Bolivian
Douglas Hardy; Mark W. Williams; Carlos Escobar
The Eight General Research Methodologies: A Facet Analysis of the Research Process.
ERIC Educational Resources Information Center
There is a need for clarity regarding different research strategies in order to assess the relative contribution of each. Using the framework of the Facet Design Technique (FDT) for problem structuring, eight general research strategies are identified as they relate to measurement fidelity, representativeness of units, and treatment
Gephart, William J.
A FACETS Analysis of Rater Bias in Measuring Japanese Second Language Writing Performance.
ERIC Educational Resources Information Center
Using FACETS, investigates how judgments of trained teacher raters are biased toward certain types of candidates and certain criteria in assessing Japanese second language writing. Explores the potential for using a modified version of a rating scale for norm-referenced decisions about Japanese second language writing ability. (Author/VWL)
Kondo-Brown, Kimi
NaCl on vicinal Cu surfaces: layer growth versus adsorbate-induced faceting
NASA Astrophysics Data System (ADS)
NaCl growth on vicinal Cu surfaces was studied by high-resolution electron diffraction and STM. The substrates used are Cu(221) which consists of (111) terraces and intrinsic (11\\overline1) steps, and Cu(532) which is a kinked (211) surface with (111) terraces and intrinsic (100) steps. On Cu(221) NaCl grows epitaxially on the flat substrate surface and forms (100)-terminated films. The polar [110] in-plane direction of the adlayer is aligned with the intrinsic Cu steps. Submonolayer deposition of NaCl on Cu(532) at 500 K to 600 K, on the other hand, induces two-dimensional substrate surface faceting. The new structure consists of nanopyramids with (111)-, (311)-, and (531)-oriented facets. NaCl grows selectively in its energetically favorable (100) termination as a single monolayer on the (311) and (531) facets, whereas the (111) facet remains uncovered. The overall growth behavior confirms that the orientational relationships observed are governed by Coulomb interactions between the ionic charges in the film and electrostatic dipoles located at steps and kinks of the vicinal metal template [1]. [1] J. Repp, S. F—lsch, G. Meyer, K.H. Rieder, Phys. Rev. Lett. (in print)
Riemann, A.; F—lsch, S.; Repp, J.; Meyer, G.; Rieder, K. H.
Migration of FACET from simulation environment to dispatcher decision support system
This paper describes the approach taken to develop AOC requirements, assess the feasibility of implementing the requirements and ongoing efforts to transfer FACET-derived technology to users of the NAS. The advances made in the state of the art for handling of flights using integrated air traffic and weather data, along with the coupled applications of risk analysis, demand forecasting and
Banavar Sridhar; K. Sheth; P. Smith; W. Leber
Construct Validity of the Five Facet Mindfulness Questionnaire in Meditating and Nonmeditating Samples
ERIC Educational Resources Information Center
Previous research on assessment of mindfulness by self-report suggests that it may include five component skills: observing, describing, acting with awareness, nonjudging of inner experience, and nonreactivity to inner experience. These elements of mindfulness can be measured with the Five Facet Mindfulness Questionnaire (FFMQ). The authors
Baer, Ruth A.; Smith, Gregory T.; Lykins, Emily; Button, Daniel; Krietemeyer, Jennifer; Sauer, Shannon; Walsh, Erin; Duggan, Danielle; Williams, J. Mark G.
Clutter properties for STAP with smooth and faceted cylindrical conformal antennas
Conformal antennas, which assume the shape of the platform, have several advantages; like reduced weight and space, aerodynamic design and increased field of view. We are interested in detection of moving ground targets with air-borne radar with faceted or smooth vertical half-cylinder or planar antennas with different subarray sizes. We simulate radar systems and study clutter properties which are important
Svante Bj—rklund; Tomas Boman; Anders Nelander
Facet-Dependent Catalytic Activity of Platinum Nanocrystals for Triiodide Reduction in Dye-Sensitized Solar Cells
Platinum (Pt) nanocrystals have demonstrated to be an effective catalyst in many heterogeneous catalytic processes. However, pioneer facets with highest activity have been reported differently for various reaction systems. Although Pt has been the most important counter electrode material for dye-sensitized solar cells (DSCs), suitable atomic arrangement on the exposed crystal facet of Pt for triiodide reduction is still inexplicable. Using density functional theory, we have investigated the catalytic reaction processes of triiodide reduction over {100}, {111} and {411} facets, indicating that the activity follows the order of Pt(111) > Pt(411) > Pt(100). Further, Pt nanocrystals mainly bounded by {100}, {111} and {411} facets were synthesized and used as counter electrode materials for DSCs. The highest photovoltaic conversion efficiency of Pt(111) in DSCs confirms the predictions of the theoretical study. These findings have deepened the understanding of the mechanism of triiodide reduction at Pt surfaces and further screened the best facet for DSCs successfully.
Zhang, Bo; Wang, Dong; Hou, Yu; Yang, Shuang; Yang, Xiao Hua; Zhong, Ju Hua; Liu, Jian; Wang, Hai Feng; Hu, P.; Zhao, Hui Jun; Yang, Hua Gui
Facet-Dependent Catalytic Activity of Platinum Nanocrystals for Triiodide Reduction in Dye-Sensitized Solar Cells
NASA Astrophysics Data System (ADS)
Platinum (Pt) nanocrystals have demonstrated to be an effective catalyst in many heterogeneous catalytic processes. However, pioneer facets with highest activity have been reported differently for various reaction systems. Although Pt has been the most important counter electrode material for dye-sensitized solar cells (DSCs), suitable atomic arrangement on the exposed crystal facet of Pt for triiodide reduction is still inexplicable. Using density functional theory, we have investigated the catalytic reaction processes of triiodide reduction over {100}, {111} and {411} facets, indicating that the activity follows the order of Pt(111) > Pt(411) > Pt(100). Further, Pt nanocrystals mainly bounded by {100}, {111} and {411} facets were synthesized and used as counter electrode materials for DSCs. The highest photovoltaic conversion efficiency of Pt(111) in DSCs confirms the predictions of the theoretical study. These findings have deepened the understanding of the mechanism of triiodide reduction at Pt surfaces and further screened the best facet for DSCs successfully.
Zhang, Bo; Wang, Dong; Hou, Yu; Yang, Shuang; Yang, Xiao Hua; Zhong, Ju Hua; Liu, Jian; Wang, Hai Feng; Hu, P.; Zhao, Hui Jun; Yang, Hua Gui
A new device used in the restoration of kinematics after total facet arthroplasty
Facet degeneration can lead to spinal stenosis and instability, and often requires stabilization. Interbody fusion is commonly performed, but it can lead to adjacent-segment disease. Dynamic posterior stabilization was performed using a total facet arthroplasty system. The total facet arthroplasty system was originally intended to restore the natural motion of the posterior stabilizers, but follow-up studies are lacking due to limited clinical use. We studied the first 14 cases (long-term follow-up) treated with this new device in our clinic. All patients were diagnosed with lumbar stenosis due to hypertrophy of the articular facets on one to three levels (maximum). Disk space was of normal height. The design of this implant allows its use only at levels L3L4 and L4L5. We implanted nine patients at the L4L5 level and four patients at level L3L4. Postoperative follow-up of the patients was obtained for an average of 3.7 years. All patients reported persistent improvement of symptoms, visual analog scale score, and Oswestry Disability Index score. Functional scores and dynamic radiographic imaging demonstrated the functional efficacy of this new implant, which represents an alternative technique and a new approach to dynamic stabilization of the vertebral column after interventions for spine decompression. The total facet arthroplasty system represents a viable option for dynamic posterior stabilization after spinal decompression. For the observed follow-up, it preserved motion without significant complications or apparent intradisk or adjacent-disk degeneration.
Vermesan, D; Prejbeanu, R; Daliborca, C Vlad; Haragus, H; Magureanu, M; Marrelli, M; Promenzio, L; Caprio, M; Cagiano, R; Tatullo, M
Complex 3D-tailored facets for optimal lighting of facades and public places
NASA Astrophysics Data System (ADS)
Due to antiquated technologies (calculation methods, regulations, lighting and luminaire concepts, production techniques) current outdoor lighting causes a lot of problems like light pollution, glare, energy waste etc. New types of luminaires, and in consequence new outdoor lighting concepts, can be created by combining advanced calculation methods for optical surfaces with recent production technologies and novel light sources such as short arc metal halide lamps. Light emitted from this small Etendue light sources can precisely be redirected by 3D-curved surfaces manufactured with injection molding, milling and aluminium metallization. The required optical design may use techniques like complex surface calculations and 3D-Tailoring. An innovative concept based on the latest findings in visual perception research is to focus the light of such short arc light sources onto a facetted secondary mirror which provides the desired illuminance distribution on a facade or a public place. These systems are designed to fulfill lighting requirements as well as providing visual comfort. Thus lamps with improved color rendering, luminous efficacy and increased lifetime are used and glare is minimized by splitting the reflector into many facets (light spot decomposition). A few examples of realized projects will be presented where such complex facetted surfaces are used to reach a special quality of light. Using novel techniques like 3D-Tailoring, each facet can be designed to individually create the desired (e.g. uniform) illuminance distribution on the target surface - in this case, a large facade. For this particular application, we chose to impose a square boundary for each facet, in order to tile the rectangular aperture of the secondary mirror without compromising efficiency.
Pohl, Wilfried; Anselm, Christian; Knoflach, Christian; Timinger, Andreas L.; Muschaweck, Julius A.; Ries, Harald
National Technical Information Service (NTIS)
This redport evaluates the stiffness for a standard tape-joint structural connection. This stiffness is frequently necessary when modeling a structure (e.g., a shock model). In general, for a standard cylindrical tape joint, the stiffness is 1.2 times gre...
R. P. Rechard
Experimental data on the axial, bending and torsional behavior of ductile cast iron pipes with rubber gasket joints is presented. Analytical expressions are provided which predict the resistance mechanisms and behavior of the joints. The bending mechanism is found to be quite different from the axial and torsional mechanism. By repeating the tests in a specially designed soil box, the
Investigation of joint disease
The role of nuclear medicine in the diagnosis and management of the major arthropathies is critically reviewed, with particular reference to osteoarthritis, rheumatoid and similar forms of arthritis, ankylosing spondylitis, non-specific back pain, gout, the neuropathic joint, avascular necrosis, infection and the consequences of prosthetic joint insertion. Attention is drawn both to practical applications and deficiencies in current techniques and
M. V. Merrick
Infections involving bone and joint are a significant cause of morbidity and mortality. They can result in prolonged hospital stays, long courses of systemic antibiotics and frequently will require surgical intervention. In this review we will cover the commonest infections seen clinically. We have also chosen to divide the review into two sections; infections involving native tissue\\/joints and infections relating
Tom Darton; Robert Townsend
Campylobacter prosthetic joint infection.
A 75-year-old man was diagnosed with probable Campylobacter jejuni prosthetic knee infection after a diarrheal illness. Joint aspirate and operative cultures were negative, but PCR of prosthesis sonicate fluid was positive, as was stool culture. Nineteen additional cases of Campylobacter prosthetic joint infection reported in the literature are reviewed. PMID:24523462
Vasoo, Shawn; Schwab, Jeramy J; Cunningham, Scott A; Robinson, Trisha J; Cass, Joseph R; Berbari, Elie F; Walker, Randall C; Osmon, Douglas R; Patel, Robin
National Technical Information Service (NTIS)
An artificial manually positionable elbow joint for use in an upper extremity, above-elbow, prosthetic which provides a locking feature that is easily controlled by the wearer is described. The instant elbow joint is very strong and durable to withstand t...
B. Weddendorf
The Joint Warfare System (JWARS) is a campaign-level model of military operations that is currently being developed under contract by the Office of the Secretary of Defense (OSD) for use by OSD, the Joint Staff, the Services, and the War fighting Commands. The behavior of military forces can be simulated from ports of embarkation through to their activities in combat.
A. Simlote
General joint laxity is measured with the hyperextensometer, and by analyzing the values obtained in a group of European subjects norm curves are drawn up related to age and sex. The values found in various orthopedic diseases are put into these curves, and the importance of general joint laxity is discussed.
L. Dubs; N. Gschwend
National Technical Information Service (NTIS)
Three major experimental field installations of approximately 7 types of joint sealing materials were used to compare and evaluate the products of numerous sealant manufacturers. The sealants were placed in contraction joints (3/8 in. x 2 in.) which were ...
J. G. F. Hiss J. R. Lambert W. M. McCarty
Superconducting cable joint resistance
This paper reports on results of a parametric study of the 4.2 K resistance of lap joints between two 27-strand cables of multifilamentary Nb{sub 3}Sn wire. All joints were between ribbon terminations made rolling copper-encapsulated cable ends flat. Resistances as functions of current were inferred from current decay time constants of cable-in-conduit conductor loops connected by the joints. The resistances of twenty three samples were measured (range of 0.2 to 3 n{Omega}). It was found that lap joint resistance was a function of current. The influences of solder versus no solder, solder thickness, indium versus tin-lead, ribbon surface oxidation, solder flux, cable twist pitch, wire chrome plating, clamping pressure during heat treatment, ribbon aspect ratio, and joint length are reported.
Herbelot, O.; Steeves, M.M.; Hoening, M.O. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center)
Influence of misfit strain on {311} facet development in selective epitaxial growth of Si 1? x Ge x \\/Si(100) grown by gas-source molecular beam epitaxy
Selective epitaxy of Si1?xGex\\/Si(100) via gas-source molecular beam epitaxy was carried out to compare facet formations in Si1?xGex to Si. A single {311} facet with a pronounced cusp at the intersection with the (100) surface was observed in large windows (25 ?m). However, facet formations occurring within smaller windows (?5 ?m) show the development of {311}- and {111}- type facets.
Greg D. U'Ren; Mark S Goorsky; Kang L Wang
Cover For Duct Expansion Joint
NASA Technical Reports Server (NTRS)
Size and shape of cover reduces stress and increases strength. Cover for expansion joints on duct-work seals tightly while accommodating movement of joint. Provides ample bonding area on both members of joint.
Brown, A. R.
Highly reactive {001} facets of TiO2-based composites: synthesis, formation mechanism and characterization
NASA Astrophysics Data System (ADS)
Titanium dioxide (TiO2) is one of the most widely investigated metal oxides due to its extraordinary surface, electronic and catalytic properties. However, the large band gap of TiO2 and massive recombination of photogenerated electron-hole pairs limit its photocatalytic and photovoltaic efficiency. Therefore, increasing research attention is now being directed towards engineering the surface structure of TiO2 at the most fundamental and atomic level namely morphological control of {001} facets in the range of microscale and nanoscale to fine-tune its physicochemical properties, which could ultimately lead to the optimization of its selectivity and reactivity. The synthesis of {001}-faceted TiO2 is currently one of the most active interdisciplinary research areas and demonstrations of catalytic enhancement are abundant. Modifications such as metal and non-metal doping have also been extensively studied to extend its band gap to the visible light region. This steady progress has demonstrated that TiO2-based composites with {001} facets are playing and will continue to play an indispensable role in the environmental remediation and in the search for clean and renewable energy technologies. This review encompasses the state-of-the-art research activities and latest advancements in the design of highly reactive {001} facet-dominated TiO2via various strategies, including hydrothermal/solvothermal, high temperature gas phase reactions and non-hydrolytic alcoholysis methods. The stabilization of {001} facets using fluorine-containing species and fluorine-free capping agents is also critically discussed in this review. To overcome the large band gap of TiO2 and rapid recombination of photogenerated charge carriers, modifications are carried out to manipulate its electronic band structure, including transition metal doping, noble metal doping, non-metal doping and incorporating graphene as a two-dimensional (2D) catalyst support. The advancements made in these aspects are thoroughly examined, with additional insights related to the charge transfer events for each strategy of the modified-TiO2 composites. Finally, we offer a summary and some invigorating perspectives on the major challenges and new research directions for future exploitation in this emerging frontier, which we hope will advance us to rationally harness the outstanding structural and electronic properties of {001} facets for various environmental and energy-related applications.
Ong, Wee-Jun; Tan, Lling-Lling; Chai, Siang-Piao; Yong, Siek-Ting; Mohamed, Abdul Rahman
\\{311\\} facets of selectively grown epitaxial Si layers on SiO2-patterned Si(100) surfaces
NASA Astrophysics Data System (ADS)
A Si epitaxial layer was selectively grown on SiO2-patterned Si(100) with no miscut and on 1¯, 3¯, and 4¯ miscut vicinal surfaces by ultrahigh-vacuum chemical-vapor deposition using disilane. On the patterned Si(100) surfaces with and without miscuts, faceted (100) layers grew. Although \\{111\\} is energetically the most stable surface, the resulting facets had \\{311\\} orientation. This means that the \\{311\\} faceting is related to the growth kinetics rather than the energetics. Macroscopically, the \\{311\\} faceting is caused by the slower growth rate of the (311) surface than that of the (100) surface. On the vicinal surfaces, the top surface of the selectively grown layer was not vicinal but had exactly (100) orientation. This indicates the ready incorporation of adatoms into the step edges of (100) terraces and the subsequent step-flow growth mode. When the flowing step reaches the end of the top surface, it is swallowed into the facet and disappears. This decreases the step density and makes the vicinal surface flat. With respect to the swallowing of the growing steps at the facet corner, we propose a microscopic model for the \\{311\\} faceting.
Hirayama, Hiroyuki; Hiroi, Masayuki; Ide, Takashi
Development of big five domains and facets in adulthood: mean-level age trends and broadly versus narrowly acting mechanisms.
Data from a cross-sectional sample (N?=?601 men and women) and a longitudinal sample (N?=?125 women) were used to test hypotheses about the development of Big Five domains and facets from early adulthood through middle age. Analyses of mean-level age trends indicated that overall Agreeableness and Conscientiousness increased with age and that several facets showed distinctive trends that replicated across the samples. Cross-sectional analyses of trait intercorrelations and covariances indicated that interrelations between the Big Five domains, and between their more specific facets, were quite similar at older versus younger ages. Finally, longitudinal analyses of individual-level changes indicated that (a) different people's personalities changed in markedly different ways; (b) these changes were predominantly independent, rather than correlated, across Big Five domains; and (c) the pattern of change correlations between Big Five facets could be explained by the facets' interrelations at the first assessment time. Taken together, these results suggest that a complete understanding of personality development requires consideration of facet-level traits and that adult personality development is predominantly influenced by narrowly acting mechanisms that each affect a single Big Five domain, or a small cluster of related facets, rather than by broadly acting mechanisms that simultaneously affect previously independent traits. PMID:22091969
Soto, Christopher J; John, Oliver P
Multi-wavelength light emission from three-dimensional AlGaN quantum wells fabricated on facet structures
NASA Astrophysics Data System (ADS)
Faceted three-dimensional (3D) AlGaN/AlN multiple quantum wells (MQWs) with semipolar {1?101} and polar (0001) planes are fabricated by a regrowth technique based on metalorganic vapor phase epitaxy (MOVPE) on trench-patterned AlN templates. Similar 3D microfacet structures with different height are formed on top of and at the bottom of the AlN trench. Cathodoluminescence (CL) spectra are separately acquired at semipolar and (0001) facet QWs at room temperature (RT). The peak energies of {1?101} facet QWs and (0001) facet QWs on higher 3D structures are 5.42 and 5.43 eV, respectively, while that of (0001) facet QWs on lower 3D structures is 5.23eV. Through structural analyses using transmission electron microscopy (TEM), the peak energy difference between the {1?101} QWs and the lower (0001) QWs is ascribed mainly to suppressed internal electric fields in the {1?101} facet QWs. Furthermore, Al spatial distribution causes the peak energy difference between the (0001) facet QWs.
Kataoka, Ken; Yamaguchi, Masanori; Fukushima, Kensuke; Funato, Mitsuru; Kawakami, Yoichi
Role of poly(vinylpyrrolidone) (PVP) and other sterically protecting polymers in selective stabilization of {111} and {100} facets in pentagonally twinned silver nanoparticles.
The role of PVP in the selective formation of pentagonally twinned silver nanoparticle morphologies and the corresponding selective facet stabilization is elucidated. Both for decahedral and pentagonal rod nanoparticles, PVP does not promote specific facet selection but is instrumental in colloidal stabilization and facet preservation through steric protection. PMID:24336687
Murshid, Nimer; Kitaev, Vladimir
Appendicular joint dislocations.
This study defines the incidence and epidemiology of joint dislocations and subluxations of the appendicular skeleton. All patients presenting acutely to hospital with a dislocation or subluxation of the appendicular skeleton from a defined population were included in the study. There were 974 dislocations or subluxations over one year between the 1st November 2008 and the 31st October 2009. There was an overall joint dislocation incidence of 157/10(5)/year (188/10(5)/year in males and 128/10(5)/year in females). Males demonstrated a bimodal distribution with a peak incidence of 446/10(5)/year at 15-24 years old and another of 349/10(5)/year in those over 90 years. Females demonstrate an increasing incidence from the seventh decade with a maximum incidence of 520/10(5)/year in those over 90 years. The most commonly affected joints are the glenohumeral (51.2/10(5)/year), the small joints of the hand (29.9/10(5)/year), the patellofemoral joint (21.6/10(5)/year), the prosthetic hip (19.0/10(5)/year), the ankle (11.5/10(5)/year), the acromioclavicular joint (8.9/10(5)/year) and the elbow (5.5/10(5)/year). Unlike fractures, dislocations are more common in the both the most affluent and the most socially deprived sections of the population. Joint disruptions are more common than previously estimated. PMID:23433660
Hindle, Paul; Davidson, Eleanor K; Biant, Leela C; Court-Brown, Charles M
NASA Technical Reports Server (NTRS)
An airtight, flexible joint is disclosed for the interfacing of two pressure vessels such as between the Space Station docking tunnel and the Space Shuttle Orbiter bulkhead adapter. The joint provides for flexibility while still retaining a structural link between the two vessels required due to the loading created by the internal/external pressure differential. The joint design provides for limiting the axial load carried across the joint to a specific value, a function returned in the Orbiter/Station tunnel interface. The flex joint comprises a floating structural segment which is permanently attached to one of the pressure vessels through the use of an inflatable seal. The geometric configuration of the joint causes the tension between the vessels created by the internal gas pressure to compress the inflatable seal. The inflation pressure of the seal is kept at a value above the internal/external pressure differential of the vessels in order to maintain a controlled distance between the floating segment and pressure vessel. The inflatable seal consists of either a hollow torus-shaped flexible bladder or two rolling convoluted diaphragm seals which may be reinforced by a system of straps or fabric anchored to the hard structures. The joint acts as a flexible link to allow both angular motion and lateral displacement while it still contains the internal pressure and holds the axial tension between the vessels.
Kahn, Jon B. (inventor)
NASA Technical Reports Server (NTRS)
Compliant joints devised to accommodate misalignments of tools and/or workpieces with respect to robotic manipulators. Has characteristics and appearance of both universal-joint and cable-spring-type flexible shaft coupling. Compliance derived from elastic properties of short pieces of cable. Compliance of joint determined by lengths, distances between, relative orientations, thickness of strands, number of strands, material, amount of pretwist, and number of short pieces of cable. Worm-drive mechanism used to adjust lengths to vary compliance as needed during operation.
Kerley, James J., Jr.
High-power, low-lateral divergence broad area quantum cascade lasers with a tilted front facet
NASA Astrophysics Data System (ADS)
We introduce a simple technique to improve the beam quality of broad area quantum cascade lasers. Moderately tilted front facets of the laser provide suppression of higher order lateral waveguide modes. A device with a width of 60 ?m and a front facet angle of 17¯ shows a nearly diffraction limited beam profile. In addition, the peak output power and the slope efficiency of the device are increased since most of the light inside the cavity is emitted through the tilted front facet by an asymmetric light intensity distribution along the cavity.
Ahn, Sangil; Schwarzer, Clemens; Zederbauer, Tobias; MacFarland, Donald C.; Detz, Hermann; Andrews, Aaron M.; Schrenk, Werner; Strasser, Gottfried
DEM evaluation by an operator and facets stereo vision: a comparison based on close-range imagery
NASA Astrophysics Data System (ADS)
In this paper we compare the results of DEM estimation by a photogrammetric operator with the analytic plotter LEICA AC3 and an automatic object space based reconstruction method (Facets Stereo Vision). We are working with close-range images of natural stone surfaces, taken in cooperation with curators of monuments to monitor the weathering of stones. Two windows representative of the surface were selected and DEMs evaluated by an operator and Facets Stereo Vision. For the computation with Facets Stereo Vision a horizontal plane was introduced as initial value. Image pyramid techniques were applied for the final DEM estimation. Differences, problems of the comparison, and the results are discussed.
Kempa, M.; Schlueter, Martin
Reconstructing cultural behavior from dental wear studies: Is para-facets analysis approach scientifically valid?
It is common knowledge, that in archaic populations teeth were used as tools, this behavior can be studied by evaluating attrition patterns. Parafacets were defined as nonmasticatory wear areas that have no antagonist matching wear facets. The presence of the parafacets led to far-reaching conclusions regarding cultural interactions between Near Eastern Neanderthals and anatomically modern humans. This study was aimed to examine the identification of parafacets in some of the Qafzeh specimens. Based on findings of our research we suggest that the attrition facets mistakenly considered as parafacets are in fact the result of the static and dynamic occlusion. Therefore the observations induce much less dramatic interpretation. We here propose several guidelines that would be beneficial in that they aim to evaluate the parafacets with heightened accuracy. PMID:24767822
Sarig, Rachel; Tillier, Anne-Marie
An experiential thinking style: its facets and relations with objective and subjective criterion measures.
In Study 1, an experiential factor divided into the following 3 factors when 3 or more factors were extracted: intuition, emotionality, and imagination; whereas a rational factor retained its coherence. In Study 2, an experiential but not a rational thinking style was positively associated with performance measures of creativity, humor, aesthetic judgment, and intuition and with self-report measures of empathy and social popularity. A rational thinking style was associated with several measures of adjustment. Both thinking styles were positively related to personal growth. Support was provided from several sources for the discriminant validity of the experiential facets. In a third study, the independence of the 2 thinking styles and of gender differences in self-reported data were verified by observations by others of participants' thinking styles. The importance of identifying facets of an experiential thinking style and of discovering previously unrecognized favorable attributes of this thinking style was discussed. PMID:21241307
Norris, Paul; Epstein, Seymour
Insights on the facet specific adsorption of amino acids and peptides toward platinum.
Engineering shape-controlled bionanomaterials requires comprehensive understanding of interactions between biomolecules and inorganic surfaces. We explore the origin of facet-selective binding of peptides adsorbed onto Pt(100) and Pt(111) crystallographic planes. Using molecular dynamics simulations, we show that upon adsorption the peptides adopt a predictable conformation. We compute the binding energies of the amino acids constituting two adhesion peptides for Pt, S7, and T7 and demonstrate that peptides' surface recognition behavior that makes them unique among populations originates from differential adsorption of their building blocks. We find that the degree of peptide binding is mainly due to polar amino acids and the molecular architecture of the peptides close to the Pt facets. Our analysis is a first step in the prediction of enhanced affinity between inorganic materials and a peptides, toward the synthesis of novel nanomaterials with programmable shape, structure, and properties. PMID:24289530
Ramakrishnan, Sathish Kumar; Martin, Marta; Cloitre, Thierry; Firlej, Lucyna; Cuisinier, FrÕdÕric J G; Gergely, Csilla
Associations among childhood abuse and psychopathy facets in male sexual offenders.
In the search for causes of psychopathy, the literature historically focuses on biological and temperamental differences. In comparison, this literature overshadows that of psychosocial risk factors for the development of psychopathy, namely childhood maltreatment. The current study examines the association between specific types of maltreatment (i.e., physical, emotional, sexual abuse, neglect) and PCL-R total and facet scores among a sample of 223 adult men convicted of sexual offenses and evaluated for civil commitment. Results indicate that childhood sexual abuse is associated with higher PCL-R total scores and facets tapping a grandiose and manipulative interpersonal style, impulsive-irresponsible lifestyle, and antisocial behavior. Also, childhood physical abuse and neglect are associated with antisocial behavior. Emotional detachment traits of psychopathy (i.e., lack of empathy, shallow affect) are associated with childhood neglect for child molesters, although rapists scored higher on these traits irrespective of neglect history. Theoretical and practical implications are discussed. PMID:22448862
Graham, Nicole; Kimonis, Eva R; Wasserman, Adam L; Kline, Suzonne M
Axis-oriented, continuous anatase titania films with exposed reactive {100} facets.
Homogeneous TiO2 single crystals with high exposure of {100} reactive facets were constructed as a seed monolayer on transparent conductive substrates with the desired orientation of reactive facets. A secondary growth process was subsequently carried out on the monolayer seed film to form an axis-oriented continuous reactive film. Performing secondary growth with different precursors led to optimized conditions for high-performance photoelectrochemical activity of anatase TiO2 films. Experimental techniques such as UV/Vis absorption spectroscopy, X-ray diffraction, high-resolution SEM, and photoelectrochemistry were used to characterize the structural, optical, and photoelectrochemical properties of the as-synthesized films. As a photoanode in a photoelectrochemical cell, the axis-oriented reactive film shows a maximum photocurrent density of 0.3 mA cm(-2), as opposed to 0.075 mA cm(-2) for non-axis-oriented (randomly oriented) TiO2 film. PMID:23733736
Van, Thanh-Khue; Nguyen, Cuong Ky; Kang, Young Soo
Structural, vibrational and electronic properties of faceted GaN (0001₤) surfaces
NASA Astrophysics Data System (ADS)
We report on our investigations of the structural, vibrational and electronic properties of GaN epilayers grown on sapphire(0001). By a combination of high-resolution electron energy-loss spectroscopy (HREELS) and angular-resolved X-ray photoelectron spectroscopy (ARXPS) the orientation of the layers is determined to be (0001₤). Parts of the surface contain facets that are made of (101₤2₤)-type planes, as found using low-energy electron diffraction (LEED). We observe the dissociative adsorption of water from the residual gas at the GaN(0001₤) surface. N?H and Ga?H stretching vibrations observed in hydrogenation experiments can be correlated to adsorption on terraces and facets, respectively. Finally, we report the observation of the conduction-band surface plasmon and use theoretical simulation of the HREEL spectra to extract important semiconductor parameters such as band bending, doping level and electron mobility.
Sloboshanin, S.; Tautz, F. S.; Polyakov, V. M.; Starke, U.; Usikov, A. S.; Ber, B. Ja; Schaefer, J. A.
Heritability of the Big Five Personality Dimensions and Their Facets: A Twin Study
ABSTRACT The genetic and environmental,etiology of the five-factor model of personality as measured by the revised NEO Personality Inventory (NEO-PI-R) was assessed using 123 pairs of identical twins and 127 pairs of fraternal twins. Broad genetic influence on the five dimensions of Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness was estimated at 41%, 53%, 61%, 41%, and 44%, respectively. The facet
Kerry L. Jang; W. John Livesley; Philip A. Vemon
Abnormal grain growth and grain boundary faceting in a model Ni-base superalloy
Normal or abnormal grain growth in a model Ni-base superalloy is observed to depend on the grain boundary structure when heat-treated in a solid solution temperature range above the solvus temperature (1150¯C) of the ?? phase. When heat-treated at 1200¯C abnormal grain growth occurs and most of the grain boundaries are observed to be faceted by optical microscopy, transmission electron
S. B Lee; D. Y Yoon; M. F Henry
Differential effects on facets of attention in adolescents prenatally exposed to cigarettes and marihuana
Facets of attention were examined in 152 13- to 16-year-old adolescents for whom prenatal exposure to marihuana and cigarettes had been ascertained. The subjects, participants in an ongoing longitudinal study, were from a low-risk, predominantly middle-class sample. The assessment battery included 11 variables derived from a Continuous Performance Test, the Wisconsin Card Sorting Test, the Stroop Test, a number of
P. A Fried; Barbara Watkinson
First results from core-edge parallel composition in the FACETS project.
FACETS (Framework Application for Core-Edge Transport Simulations), now in its second year, has achieved its first coupled core-edge transport simulations. In the process, a number of accompanying accomplishments were achieved. These include a new parallel core component, a new wall component, improvements in edge and source components, and the framework for coupling all of this together. These accomplishments were a result of an interdisciplinary collaboration among computational physics, computer scientists, and applied mathematicians on the team.
Cary, J. R.; Candy, J.; Cohen, R. H.; Krasheninnikov, S.; McCune, D. C.; Estep, D. J.; Larson, J.; Malony, A. D.; Pankin, A.; Worley, P. H.; Carlsson, J. A.; Hakim, A. H.; Hamill, P.; Kruger, S.; Miah, M.; Muzsala, S.; Pletzer, A.; Shasharina, S.; Wade-Stein, D.; Wang, N.; Balay, S.; McInnes, L.; Zhang, H.; Casper, T.; Diachin, L. (Mathematics and Computer Science); (Tech-X Corp.); (General Atomics); (LLNL); (Univ. of California at San Diego); (Princeton Plasma Physics Lab.); (Colorado State Univ.); (ParaTools Inc.); (Lehigh Univ.); (ORNL)
First results from core-edge parallel composition in the FACETS project
FACETS (Framework Application for Core-Edge Transport Simulations), now in its second year, has achieved its first coupled core-edge transport simulations. In the process, a number of accompanying accomplishments were achieved. These include a new parallel core component, a new wall component, improvements in edge and source components, and the framework for coupling all of this together. These accomplishments were a result of an interdisciplinary collaboration among computational physics, computer scientists, and applied mathematicians on the team.
Cary, John R. [Tech-X Corporation; Candy, Jeff [General Atomics; Cohen, Ronald H. [Lawrence Livermore National Laboratory (LLNL); Krasheninnikov, Sergei [University of California, San Diego; McCune, Douglas [Princeton Plasma Physics Laboratory (PPPL); Estep, Donald J [Colorado State University, Fort Collins; Larson, Jay [Argonne National Laboratory (ANL); Malony, Allen [University of Oregon; Pankin, A. [Lehigh University, Bethlehem, PA; Worley, Patrick H [ORNL; Carlsson, Johann [Tech-X Corporation; Hakim, A H [Tech-X Corporation; Hamill, P [Tech-X Corporation; Kruger, Scott [Tech-X Corporation; Miah, Mahmood [Tech-X Corporation; Muzsala, S [Tech-X Corporation; Pletzer, Alexander [Tech-X Corporation; Shasharina, Svetlana [Tech-X Corporation; Wade-Stein, D [Tech-X Corporation; Wang, N [Tech-X Corporation; Balay, Satish [Argonne National Laboratory (ANL); McInnes, Lois [Argonne National Laboratory (ANL); Zhang, Hong [Argonne National Laboratory (ANL); Casper, T. A. [Lawrence Livermore National Laboratory (LLNL); Diachin, Lori [Lawrence Livermore National Laboratory (LLNL); Epperly, Thomas [Lawrence Livermore National Laboratory (LLNL); Rognlien, T. D. [Lawrence Livermore National Laboratory (LLNL); Fahey, Mark R [ORNL; Cobb, John W [ORNL; Morris, A [University of Oregon; Shende, Sameer [University of Oregon; Hammett, Greg [Princeton Plasma Physics Laboratory (PPPL); Indireshkumar, K [Tech-X Corporation; Stotler, D. [Princeton Plasma Physics Laboratory (PPPL); Pigarov, A [University of California, San Diego
... bursa or tendon sheath to treat bursitis and tendonitis, respectively. What benefit is derived from a joint ... conditions, such as rheumatoid arthritis, psoriatic arthritis, gout, tendonitis, bursitis and, occasionally, osteoarthritis. What usually is injected ...
Joint Contingency Contracting.
National Technical Information Service (NTIS)
The purpose of this Master of Business Administration (MBA) Professional Report is to investigate and analyze the means by which Contingency Contracting Officers (CCO) can effectively operate in a Joint contingency environment and to validate the Defense ...
E. K. Johnson B. H. Paton E. W. Threat L. A. Haptonstall
Joint Aspiration (Arthrocentesis)
... arthritis, or JRA), systemic lupus erythematosus (SLE), and Lyme disease. Joint aspiration is diagnostic but it also can ... Parents MORE ON THIS TOPIC Evaluate Your Child's Lyme Disease Risk Juvenile Idiopathic Arthritis Living With Lupus Bones, ...
... Dental Research Loan Repayment Programs NIH Loan Repayment Programs ... glide along the joint socket of the temporal bone. The condyles slide back to their original position when we close our mouths. To keep ...
Acromioclavicular Joint Separations.
National Technical Information Service (NTIS)
Acromioclavicular (AC) joint separations are common injuries of the shoulder girdle, especially in the young and active population. Typically the mechanism of this injury is a direct force against the lateral aspect of the adducted shoulder, the magnitude...
F. Martetschlaeger P. J. Millett R. J. Warth T. R. Gaskill
Heuristics for Joint Architecting.
National Technical Information Service (NTIS)
There is no question that Department of Defense and chairman of the Joint Chiefs of Staff directives have increased the development of operational and systems architectures. The DoD Architectural Framework (DoDAF) and its associated governing publications...
A. Piepkorn G. J. Miller J. Kennedy R. Mills T. Wieser
Gram stain of joint fluid ... result means no bacteria are present on the Gram stain. Note: Normal value ranges may vary slightly ... Abnormal results mean bacteria were seen on the Gram stain. This may be a sign of a ...
Validation of Hindi Translation of SRPB Facets of WHOQOL-SRPB Scale
Background: World Health Organization's Quality of Life Spirituality, Religiousness and Personal Beliefs Scale (WHOQOL SRPB) is a valuable instrument for assessing spirituality and religiousness. The absence of this self-administered instrument in Hindi, which is a major language in India, is an important limitation in using this scale. Aim: To translate the English version of the SRPB facets of WHOQOL-SRPB scale to Hindi and evaluate its psychometric properties. Materials and Methods: The SRPB facets were translated into Hindi using the World Health Organisation's translation methodology. The translated Hindi version was evaluated for cross-language equivalence, test-retest reliability, internal consistency, and split half reliability. Results: Hindi version was found to have good cross-language equivalence and test-retest reliability at the level of facets. Twenty-six of the 32 items and 30 of the 32 items had a significant correlation (?<0.001) in cross language concordance and test-retest reliability data, respectively. The Cronbach's alpha was 0.93, and the Spearman-Brown Sphericity value was 0.91 for the Hindi version of SRPB. Conclusions: The present study shows that cross-language equivalence, internal consistency, split-half reliability, and test-retest reliability of the Hindi version of SRPB (of WHOQOL-SRPB) are excellent. Thus, the Hindi version of WHOQOL-SRPB as translated in this study is a valid instrument.
Grover, Sandeep; Shah, Ruchita; Kulhara, Parmanand
An improved algorithm for facet-based infrared small target detection
NASA Astrophysics Data System (ADS)
Infrared small target detection is an important research area of computer vision and often a key technique in Infrared Search and Track (IRST) systems. Many algorithms have been reported for this purpose. The facet-based method is one of novel algorithms and is shown as robust and efficient, but it does not perform well in target preservation. The method cannot detect peripheral pixel of target, which causes information loss of target intensity distribution and affects post processing of detection, such as target tracking and recognition. In this paper an improved algorithm is developed for solving this shortcoming. The detection behavior of the facet model is further analyzed. Small target is surrounded by background, so local image edge that indicates target contour can be represented by zero-crossings of the second partial derivatives. The improved algorithm uses facet model to fit local intensity surface and detect potential targets using extremum theory, then the zero-crossings of the second partial derivatives of the fitting function in each potential target's neighborhood are found and the pixels inside the zero-crossing contour are restored to the potential target. In experiments involving typical infrared images target intensity distribution information is well preserved by proposed algorithm and its execution time is also acceptable.
Yi, Kejia; Deng, Tingquan; Guan, Jing; Wang, Gongze; Chen, Hao
Ga-polar GaN nanocolumn arrays with semipolar faceted tips
NASA Astrophysics Data System (ADS)
Selective area growth of GaN nanocolumns (NCs) by molecular beam epitaxy on laser ablated pre-patterned GaN(0001) templates is shown to provide regular arrays of Ga-polar NCs. The Ga diffusion-assisted growth mechanism is analyzed and the experiments suggest that the effective growth conditions vary with the height of the NCs due to Ga diffusion on the mask and the NC sidewalls, ranging from N-rich up to stoichiometry. The obtained morphology with semipolar facets at the tip is discussed within the framework of equilibrium thermodynamics, which provides a consistent picture also for the growth of N-polar NCs with flat tips. The structural investigation reveals almost defect-free semipolar \\{1\\overline {1}02\\} GaN facets at the top of the NCs, which is known to be a promising way of producing templates for nanoscale semipolar GaN-based heterostructures. Almost no polarization discontinuity is expected for InxGa1-xN/GaN interfaces on such facets.
Urban, A.; Malindretos, J.; Klein-Wiele, J.-H.; Simon, P.; Rizzi, A.
A joint's normal mechanical history contributes to the maintenance of articular cartilage and underlying bone. Loading facilitates the flow of nutrients into cartilage and waste products away, and additionally provides the mechanical signals essential for normal cell and tissue maintenance. Deleteriously low or high contact stresses have been presumed to result in joint deterioration, and particular aspects of the mechanical environment may facilitate repair of damaged cartilage. For decades, investigators have explored static joint contact stresses (under some more or less arbitrary condition) as a surrogate of the relevant mechanical history. Contact stresses have been estimated in vitro in many joints and in a number of species, although only rarely in vivo. Despite a number of widely varying techniques (and spatial resolutions) to measure these contact stresses, reported ranges of static peak normal stresses are relatively similar from joint to joint across species, and in the range of 0.5 to 5.0 MPa. This suggests vertebrate diarthrodial joints have evolved to achieve similar mechanical design criteria. Available evidence also suggests some disorders of cartilage deterioration are associated with somewhat higher peak pressures ranging from 1-20 MPa, but overlapping the range of normal pressures. Some evidence and considerable logic suggests static contact stresses per se do not predict cartilage responses, but rather temporal aspects of the contact stress history. Static contact stresses may therefore not be a reasonable surrogate for biomechanical studies. Rather, temporal and spatial aspects of the loading history undoubtedly induce beneficial and deleterious biological responses. Finally, since all articular cartilage experiences similar stresses, the concept of a "weight-bearing" versus a "non-weight-bearing" joint seems flawed, and should be abandoned.
Brand, Richard A
Prosthetic joint infections represent a major therapeutic challenge for both healthcare providers and patients. This paper reviews the predisposing factors, pathogenesis, microbiology, diagnosis, treatment and prophylaxis of prosthetic joint infection. The most optimal management strategy should be identified based on a number of considerations including type and duration of infection, antimicrobial susceptibility of the infecting pathogen, condition of infected tissues and bone stock, patient wishes and functional status.
Aslam, Saima; Darouiche, Rabih O.
Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.
Ward, Michael E. (Poway, CA); Harkins, Bruce D. (San Diego, CA)
Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 4 figures.
Ward, M.E.; Harkins, B.D.
Biomechanics of the patellofemoral joint and its clinical relevance.
An analysis of the patellofemoral joint based on experimental determinations of pressure distributions on the patellar cartilage and vectorial calculations is presented. The extension torque of all quadriceps muscles is similar. The force transmitted to the patella by the retinacula is small in all knee positions. Because the rigid patella has its own lever arms and tendon insertions at different heights, the forces on patellar and quadriceps tendons are unequal. The small patellar contact areas change according to flexion and are dependent on quadriceps force. Retropatellar pressure is thereby limited and becomes independent of flexion angle. By virtue of the direct force transmission of the quadriceps tendon to the femur, the increase in the retropatellar force is strongly limited beyond 70 degrees. The lateral-to-medial ratio of contact areas, pressing forces, cartilage areas, and bone mass is always 1.6:1, whereas the mean pressure is the same on both facets. The osseous form of the patella does not allow identification of dysplasia because cartilage compensates for apparent incongruence, especially about the medial ridge. This permits the rigid patella to adapt itself to very different abutments. Its individual form results from functional adaptation and does not explain chondromalacia. The ventralization of the tibial tuberosity does not alter retropatellar loading. The mediodistal transfer results in a high increase of pressure on both facets. PMID:2394060
Hehne, H J
Spatial separation of photogenerated electrons and holes among {010} and {110} crystal facets of BiVO4.
Charge separation is crucial for increasing the activity of semiconductor-based photocatalysts, especially in water splitting reactions. Here we show, using monoclinic bismuth vanadate crystal as a model photocatalyst, that efficient charge separation can be achieved on different crystal facets, as evidenced by the reduction reaction with photogenerated electrons and oxidation reaction with photogenerated holes, which take place separately on the {010} and {110} facets under photo-irradiation. Based on this finding, the reduction and oxidation cocatalysts are selectively deposited on the {010} and {110} facets respectively, resulting in much higher activity in both photocatalytic and photoelectrocatalytic water oxidation reactions, compared with the photocatalyst with randomly distributed cocatalysts. These results show that the photogenrated electrons and holes can be separated between the different facets of semiconductor crystals. This finding may be useful in semiconductor physics and chemistry to construct highly efficient solar energy conversion systems. PMID:23385577
Li, Rengui; Zhang, Fuxiang; Wang, Donge; Yang, Jingxiu; Li, Mingrun; Zhu, Jian; Zhou, Xin; Han, Hongxian; Li, Can
Spatial separation of photogenerated electrons and holes among {010} and {110} crystal facets of BiVO4
NASA Astrophysics Data System (ADS)
Charge separation is crucial for increasing the activity of semiconductor-based photocatalysts, especially in water splitting reactions. Here we show, using monoclinic bismuth vanadate crystal as a model photocatalyst, that efficient charge separation can be achieved on different crystal facets, as evidenced by the reduction reaction with photogenerated electrons and oxidation reaction with photogenerated holes, which take place separately on the {010} and {110} facets under photo-irradiation. Based on this finding, the reduction and oxidation cocatalysts are selectively deposited on the {010} and {110} facets respectively, resulting in much higher activity in both photocatalytic and photoelectrocatalytic water oxidation reactions, compared with the photocatalyst with randomly distributed cocatalysts. These results show that the photogenrated electrons and holes can be separated between the different facets of semiconductor crystals. This finding may be useful in semiconductor physics and chemistry to construct highly efficient solar energy conversion systems.
Li, Rengui; Zhang, Fuxiang; Wang, Donge; Yang, Jingxiu; Li, Mingrun; Zhu, Jian; Zhou, Xin; Han, Hongxian; Li, Can
Kinetically controlled synthesis of Pt-Cu alloy concave nanocubes with high-index facets for methanol electro-oxidation.
Pt-Cu alloy concave nanocubes enclosed by high-index {511} facets were synthesized in high yields and exhibited substantially enhanced electrocatalytic properties for methanol oxidation relative to commercial Pt/C. PMID:24271020
Qi, Yue; Bian, Ting; Choi, Sang-Il; Jiang, Yingying; Jin, Chuanhong; Fu, Maoshen; Zhang, Hui; Yang, Deren
Monolithically integrated laser\\/rear-facet monitor arrays with V-groove for passive optical fiber alignment
An InGaAsP\\/InP laser monolithically integrated with a rear facet monitor and a fiber V-groove has been demonstrated for the first time. The integrated device incorporates an etched-facet laser fabricated using an in situ, multistep, reactive ion etch process. The integrated V-groove, which is etched directly into the InP substrate, is designed to enable passive alignment of an optical fiber to
Mark A. Rothman; Chan L. Shieh; Alfred J. Negri; John A. Thompson; Craig A. Armiento; Roger P. Holmstrom; Jatinder Kaur
Long-standing unilateral jumped facets at C34 with no apparent history of antecedent trauma
. We report two cases of unilateral jumped facets at C34 in reliable historians with no apparent history of neck trauma. Lack\\u000a of associated morphological abnormalities of the associated disc, adjacent vertebral bodies, and contralateral facet essentially\\u000a exclude a developmental etiology. Based on the location of the injury and the presence of chronic, osteoarthritic changes\\u000a we postulate that the jumped
Andrei I. Holodny; Vivek Sharma; Eugene Rubach
Faceting of (YEuYbCa)3(GeFe)5O12 on LPE Garnet Films
The correlations of the faceting on LPE films and the lattice mismatches between LPE films and GGG substrates were investigated, taking into consideration LPE growth conditions for (YEuYbCa)3(GeFe)5O12 in a PbO.B2O3 flux. The facets in this garnet system appeared, even when the mismatches were very small. In the case of a small mismatch, it was found that the tendency to
H. Tominaga; M. Sakai; I. Hirai; K. Yamaguchi
Adaptive phase field modeling of morphological instability and facet formation during directional solidification of SiGe alloys
NASA Astrophysics Data System (ADS)
An adaptive phase field model is used to study the morphological instability and the facet formation during a directional solidification of SiGe alloys. Using highly anisotropic surface free energy and cusp kinetic functions, as well as a proper temperature gradient, the simulated critical growth velocity for various alloy concentrations is in good agreement with classical theories and experimental observations. The simulated facet formation and kinetics are also consistent with the experiments as well.
Lin, H. K.; Chen, H. Y.; Lan, C. W.
Spontaneous resolution of symptoms associated with a facet synovial cyst in an adult female - a case report
Background: Facet cysts are implicated in neural compression in the lumbar spine. Surgery is the definitive treatment for symptomatic facet cysts since the failure rate for conservative treatment is quite high; however, the role of physical/manual medicine practitioners in the management of symptomatic facet cysts has not been well explored. This case report will add to the body of evidence of spontaneous resolution of symptoms associated with facet cysts in the chiropractic literature. Case: A 58 year old female presented with acute low back and right leg pain which she attributed to a series of exercise classes that involved frequent foot stomping. Physical examination did not elicit any objective evidence of radiculopathy but MRI and CT scans revealed a facet cyst impinging on the right L5 nerve root. Injections and surgery were recommended; however, the patients radicular symptoms completely resolved after three months without surgical intervention. Summary: There is currently a paucity of data in the literature regarding the chiropractors role in the management of symptomatic facet cysts. The case presented here has added to this literature and possible areas for future research have been explored.
Ngo, Trung; Decina, Philip; Hsu, William
Imaging by atomic force microscopy of the properties difference of the layers covering the facets created during SIMS analysis
NASA Astrophysics Data System (ADS)
Atomic force microscopy (AFM) is used in tapping mode in order to study the roughness created in the crater bottom during secondary ions mass spectrometry (SIMS) analysis in silicon, using O2+ primary ions without flooding. Previous studies of the chemical composition of the facets created during the analysis have lead to the conclusion that the facets oriented toward the O2+ beam during the ionic bombardment were close to SiO2 in composition, while the facets hidden from the beam were covered with a sub-stoichiometric oxide SiOx (with x < 2). We show that the AFM phase contrast during tapping mode observation of the facets reflects this composition difference, revealing a sharp contrast between the facets. The observed contrast may arise from the different chemical composition of the facets, leading to a different energy dissipation of the tip/sample system over Si and SiO2 due to the different properties of the materials (hardness, adhesion, etc.). As a comparison, an observation of a surface covered with SiO2 and Si (SiO2 deposed with a 90 nm or 4 nm thickness, and partially removed from a Si surface) shows the same kind of contrast.
Fares, B.; Gautier, B.; Albertini, D.; Mzerd, A.; Loghmarti, M.
Dissimilar metals joint evaluation
NASA Technical Reports Server (NTRS)
Dissimilar metals tubular joints between 2219-T851 aluminum alloy and 304L stainless steel were fabricated and tested to evaluate bonding processes. Joints were fabricated by four processes: (1) inertia (friction) weldings, where the metals are spun and forced together to create the weld; (2) explosive welding, where the metals are impacted together at high velocity; (3) co-extrusion, where the metals are extruded in contact at high temperature to promote diffusion; and (4) swaging, where residual stresses in the metals after a stretching operation maintain forced contact in mutual shear areas. Fifteen joints of each type were prepared and evaluated in a 6.35 cm (2.50 in.) O.D. size, with 0.32 cm (0.13 in.) wall thickness, and 7.6 cm (3.0 in) total length. The joints were tested to evaluate their ability to withstand pressure cycle, thermal cycle, galvanic corrosion and burst tests. Leakage tests and other non-destructive test techniques were used to evaluate the behavior of the joints, and the microstructure of the bond areas was analyzed.
Wakefield, M. E.; Apodaca, L. E.
Periprosthetic Joint Infections
Implantation of joint prostheses is becoming increasingly common, especially for the hip and knee. Infection is considered to be the most devastating of prosthesis-related complications, leading to prolonged hospitalization, repeated surgical intervention, and even definitive loss of the implant. The main risk factors to periprosthetic joint infections (PJIs) are advanced age, malnutrition, obesity, diabetes mellitus, HIV infection at an advanced stage, presence of distant infectious foci, and antecedents of arthroscopy or infection in previous arthroplasty. Joint prostheses can become infected through three different routes: direct implantation, hematogenic infection, and reactivation of latent infection. Gram-positive bacteria predominate in cases of PJI, mainly Staphylococcus aureus and Staphylococcus epidermidis. PJIs present characteristic signs that can be divided into acute and chronic manifestations. The main imaging method used in diagnosing joint prosthesis infections is X-ray. Computed tomography (CT) scan may assist in distinguishing between septic and aseptic loosening. Three-phase bone scintigraphy using technetium has high sensitivity, but low specificity. Positron emission tomography using fluorodeoxyglucose (FDG-PET) presents very divergent results in the literature. Definitive diagnosis of infection should be made by isolating the microorganism through cultures on material obtained from joint fluid puncturing, surgical wound secretions, surgical debridement procedures, or sonication fluid. Success in treating PJI depends on extensive surgical debridement and adequate and effective antibiotic therapy. Treatment in two stages using a spacer is recommended for most chronic infections in arthroplasty cases. Treatment in a single procedure is appropriate in carefully selected cases.
Lima, Ana Lucia L.; Oliveira, Priscila R.; Carvalho, Vladimir C.; Saconi, Eduardo S.; Cabrita, Henrique B.; Rodrigues, Marcelo B.
Mycotoxicological investigations on maize and groundnuts from the endemic area of Mseleni joint disease in Kwazulu.
Samples of home-grown maize and groundnuts from the endemic area of Mseleni joint disease (MJD) during four seasons (1980-1983) were examined mycologically. The mycoflora of these dietary staples included Fusarium poae and F. oxysporum, which have been implicated in the aetiology of Kashin-Beck or Urov disease, another osteo-arthrosis endemic in Siberia and China. Two other species of Fusarium, i.e. F. moniliforme and F. equiseti, implicated in syndromes of abnormal bone development in animals, were also present. The predominant fungus associated with maize kernels was F. moniliforme; two other fungi relatively frequently isolated from Mseleni maize, i.e. F. compactum and Lasiodiplodia theobromae, have not previously been reported in maize in southern Africa. The predominant fungi associated with groundnut kernels were Penicillium spp., L. theobromae, Macrophomina phaseolina and F. oxysporum. The incidence of certain fungi, particularly F. compactum, F. oxysporum and L. theobromae, appeared to be higher in dietary staples from households affected by MJD than from non-affected ones. The numbers of samples examined were, however, small and these findings need to be confirmed. Cultures of 120/322 isolates of fungi from Mseleni dietary staples proved toxic to ducklings, the most toxic species being F. compactum, F. moniliforme, F. oxysporum and Phomopsis sp. The characteristic pathological changes of MJD have, however, not been induced in experimental animals with cultures of any of these fungi. A diet containing maize and groundnuts from households affected by MJD also failed to induce the characteristic osteo-arthritic changes of MJD in rats. The dietary staples used in this experiment were, however, collected during seasons of abnormally low rainfall at Mseleni.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3961620
Marasas, W F; Van Rensburg, S J
NASA Technical Reports Server (NTRS)
Reliable, lightweight robotic joint suitable for variety of applications, actuated hydraulically, without need for heavy mechanical cylinders or gears on joint itself. Includes two members; first member rotates about pin at end of second member. Includes cam, over which tension line stretched. Ends of tension line anchored at end of second member opposite end that holds pin. Bladder placed on each side of second member, squeezed between second member and tension line. Pressures and/or amounts of fluid in bladders controlled by use of conventional equipment like pumps, valves, and reservoirs. Bladder on one side inflated more than on other side; greater inflation on one side causes greater stretching of tension line on that side. Greater tension pulls on cam, turning first member toward that side. Angle of joint controlled by controlling differential inflation of two bladders.
Robertson, Glen A.
A Faceted Shape Model Approach to Altimetry and Velocimetry for Irregularly Shaped Bodies
NASA Technical Reports Server (NTRS)
Range and velocity sensors based on lidar or radar with multiple beams are often used to measure the altitude and velocity, respectively, of a spacecraft above a targetbody. A difficulty that arises when navigating about small bodies such as asteroids or comets, is that the notion of altitude is largely obscured by the irregular shape of the target surface. This paper develops a method to incorporate the multibeam altimeter and Doppler velocimeter measurements into the on-board spacecraft state estimator by using information from a faceted shape model representation of the target body surface.
Bayard, D.S.; Brugarolas, P.B.; Broschart, S.B.
Facet-dependent optical properties of polyhedral Au-Cu2O core-shell nanocrystals
NASA Astrophysics Data System (ADS)
We fabricated Au-Cu2O core-shell octahedra, cuboctahedra, and nanocubes having sizes of 90-220 nm using 50 nm octahedral cores. The smaller particle sizes minimize the strong light scattering features from the Cu2O shells and enable the surface plasmon resonance (SPR) absorption band of the gold cores to be clearly identified. Beyond a lower shell thickness limit, the SPR band positions of the gold cores are independent of the shell thickness, but are strongly dependent on the exposed particle surfaces. The plasmonic band red-shifts from Au-Cu2O octahedra to cuboctahedra and nanocubes, and differs by as much as 26 nm between the octahedra and the nanocubes. The same facet-dependent optical effects were observed using larger octahedral gold cores and cubic gold cores. In contrast, simulation spectra show progressively red-shifted SPR band positions with increasing shell thickness. The Cu2O shells are also found to exhibit facet-dependent optical behavior. These nanocrystals can respond to changes in the solvent environment such as solvents with different refractive indices, indicating that the plasmonic field of the gold cores can extend beyond the particle surfaces despite the presence of thick shells. Plane-selective spectral responses to low concentrations of surfactants were also recorded.We fabricated Au-Cu2O core-shell octahedra, cuboctahedra, and nanocubes having sizes of 90-220 nm using 50 nm octahedral cores. The smaller particle sizes minimize the strong light scattering features from the Cu2O shells and enable the surface plasmon resonance (SPR) absorption band of the gold cores to be clearly identified. Beyond a lower shell thickness limit, the SPR band positions of the gold cores are independent of the shell thickness, but are strongly dependent on the exposed particle surfaces. The plasmonic band red-shifts from Au-Cu2O octahedra to cuboctahedra and nanocubes, and differs by as much as 26 nm between the octahedra and the nanocubes. The same facet-dependent optical effects were observed using larger octahedral gold cores and cubic gold cores. In contrast, simulation spectra show progressively red-shifted SPR band positions with increasing shell thickness. The Cu2O shells are also found to exhibit facet-dependent optical behavior. These nanocrystals can respond to changes in the solvent environment such as solvents with different refractive indices, indicating that the plasmonic field of the gold cores can extend beyond the particle surfaces despite the presence of thick shells. Plane-selective spectral responses to low concentrations of surfactants were also recorded. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr06293g
Yang, Yu-Chen; Wang, Hsiang-Ju; Whang, Jennifer; Huang, Jer-Shing; Lyu, Lian-Ming; Lin, Po-Heng; Gwo, Shangjr; Huang, Michael H.
Zinc oxide micro-spheres with faceted surfaces produced by laser ablation of zinc targets
NASA Astrophysics Data System (ADS)
We report the fabrication of ZnO micro-spheres using high-power laser ablation of Zn metal in the presence of oxygen gas background without use of any catalysts or additives. The centre-symmetric geometrical structures of ZnO micro-spheres exhibit clear pentagonal and hexagonal facets with different sizes. A discussion of the growth mechanisms based on a model of subsurface micro-explosion boiling followed by laser-surface sintering of assembled particles has been proposed to explain the formation of the ZnO micro-spheres.
Chen, Ming; Liu, Xiangdong; Liu, Yuehua; Zhao, Mingwen
New Joint Sealants. Criteria, Design and Materials.
ERIC Educational Resources Information Center
Contents include--(1) sealing concrete joints, (2) sealing glass and metal joints, (3) metal and glass joint sealants from a fabricator's viewpoint, (4) a theory of adhesion for joint sealants, (5) geometry of simple joint seals under strain, (6) joint sealant specifications from a manufacturer's viewpoint, (7) joint sealant requirements from an
Building Research Inst., Inc., Washington, DC.
Joint Fires Training Guide for a Corps Joint Task Force.
National Technical Information Service (NTIS)
A detailed analysis of responsibilities, inputs, processes, outputs, and interactions was conducted for the staff elements and cells involved in joint fires at the Corps Joint Task Force level. This research product documents that analysis. The purpose of...
J. F. Love
National Technical Information Service (NTIS)
Despite all the attention given to jointness since World War II, there is no comprehensive theory that underpins the concept in doctrine. This is unusual in light of the large body of literature on operational art. Most military practitioners find operati...
R. C. Rubel
Periprosthetic Joint Infection
The orthopedic community has begun to witness a worrisome rise in the incidence of periprosthetic joint infections (PJIs) caused by resistant organisms. Besides other challenges associated with treating these infections, it appears that these infections may pose a higher cost compared to infections caused by sensitive organisms. Significantly higher cost of care for treatment of infections due to methicillin-resistant organisms
Javad Parvizi; Ian M. Pawasarat; Khalid A. Azzam; Ashish Joshi; Erik N. Hansen; Kevin J. Bozic
NSDL National Science Digital Library
Joints are very important to problems in applied geology (fluid flow, slope stability), but three-dimensional exposures of simple joint sets are not readily accessible from my campus. I developed this exercise based on the experiments of Miller (2001) to give students hands-on practice describing and interpreting joints. For the exercise, I prepare a cornstarch-water mixture a few days in advance and pour it into plastic petri dishes. I add a "flaw" to each dish (typically a small pebble). As the cornstarch dries, vertical joints develop. In class, each group of 3-4 students is provided a petri dish of desiccated cornstarch. Students are asked to draw a map of the joints, paying particular attention to intersection angles. (The joints curve to intersect at 90 degrees.) They determine relative ages of the joints using abutting relationships. (Typically 3-6 generations of joints.) Students next dissect the sample and describe the surface textures of the larger joints and the location of the flaw. The cornstarch produces beautiful plumose structure (hackles). Students then interpret the joint propagation direction from the surface textures, and note the origin of the joint. (Typically, a first- or second-generation joint initiates at the flaw.) Students discuss the role of flaws in the initiation of joints in their groups.
Crider, Juliet
Comparison of 2 temporomandibular joint total joint prosthesis systems
Purpose: The study goal was to evaluate the comparative outcomes of patients treated with temporomandibular joint (TMJ) total joint prostheses, using either the Christensen prosthesis (TMJ Inc, Golden, CO) (CP) or the TMJ Concepts prosthesis (TMJ Concepts Inc, Camarillo, CA; formerly Techmedica Inc) (TP). Patients and Methods: Forty-five consecutive patients treated with either CP or TP total joint prostheses were
Larry M. Wolford; Douglas J. Dingwerth; Reena M. Talwar; Marcos C. Pitta
What is Joint Interdependence Anyway.
National Technical Information Service (NTIS)
There is much ado lately about the concept of 'joint interdependence' in future military operations. More than one four-star general has praised Operation Desert Storm's joint deconfliction; that is, the conduct of relatively independent service operation...
C. R. Paparone J. A. Crupi
Facets of psychopathy in relation to potentially traumatic events and posttraumatic stress disorder among female prisoners: the mediating role of borderline personality disorder traits.
Despite the high prevalence of trauma exposure in female prisoners, few studies have examined the link between psychopathy and posttraumatic stress disorder (PTSD)-or the potential mediating role of borderline personality disorder traits. Using a sample of incarcerated women, we identified differential associations across facets of psychopathy, as assessed via the Psychopathy Checklist-Revised (PCL-R; Hare, 2003), with potentially traumatic events (PTE) and symptoms of PTSD. Specifically, the Interpersonal and Affective facets were unrelated to both PTE and PTSD, while the Lifestyle and Antisocial facets were each associated with PTE and the Antisocial facet was uniquely associated with PTSD symptoms. Borderline personality disorder traits fully accounted for the association between the Antisocial facet and both PTE and PTSD, while the Lifestyle facet contributed incrementally to the prediction of PTE. The findings clarify linkages among psychopathy, trauma, PTSD, and borderline personality disorder traits, and extend our understanding of the clinical presentation of psychopathy in women. PMID:22452777
Blonigen, Daniel M; Sullivan, Elizabeth A; Hicks, Brian M; Patrick, Christopher J
Pseudocapacitive hausmannite nanoparticles with (101) facets: synthesis, characterization, and charge-transfer mechanism.
Hausmannite Mn3 O4 octahedral nanoparticles of 18.3 Ý 7.0 nm with (101) facets have been prepared by an oxygen-mediated growth. The electrochemical properties of the Mn3 O4 particles as pseudocapacitive cathode materials were characterized both in half-cells and in button-cells. The Mn3 O4 nanoparticles exhibited a high mass-specific capacitance of 261 F g(-1), which was calculated from cyclic voltammetry analyses, and a capacitive retention of 78% after 10,000 galvanostatic charge-discharge cycles. The charge-transfer mechanisms of the Mn3 O4 nanoparticles were further studied by using synchrotron-based in situ X-ray absorption near edge spectroscopy and XRD. Both measurements showed concurrently that throughout the potential window of 0-1.2?V (vs. Ag/AgCl), a stable spinel structure of Mn3 O4 remained, and a reversible electrochemical conversion between tetrahedral [Mn(II) O4 ] and octahedral [Mn(III) O6 ] units accounted for the redox activity. Density functional theory calculations further corroborated this mechanism by confirming the enhanced redox stability afforded by the abundant and exposed (101) facets of Mn3 O4 octahedra. PMID:23650213
Yeager, Matthew P; Du, Wenxin; Wang, Qi; Deskins, N Aaron; Sullivan, Matthew; Bishop, Brendan; Su, Dong; Xu, Wenqian; Senanayake, Sanjaya D; Si, Rui; Hanson, Jonathan; Teng, Xiaowei
Principal components analyses of the MMPI-2 PSY-5 scales: identification of facet subscales.
The Personality Psychopathology Five (PSY-5) is a five-factor personality trait model designed for assessing personality pathology using quantitative dimensions. Harkness, McNulty, and Ben-Porath developed Minnesota Multiphasic Personality Inventory-2 (MMPI-2) scales based on the PSY-5 model, and these scales were recently added to the standard MMPI-2 profile. Although the PSY-5 constructs are multidimensional in definition, explicit subscales for the broader PSY-5 scales have not been developed. The primary goals of this study were to empirically derive subscales for the MMPI-2 PSY-5 scales using principal components analysis (PCA) and to replicate these subscales with an independent sample. Individual PSY-5 scales were analyzed using PCA with an initial sample of 4,325 MMPI-2 protocols, and the component structure was replicated with a second sample of 4,277 MMPI-2 protocols. A third sample of 4,327 protocols was used to further evaluate the internal consistency reliabilities of the resulting facet subscales. Overall, replicable facet subscales were identified with content areas that are largely congruent with Harkness and McNulty's model. PMID:15914720
Arnau, Randolph C; Handel, Richard W; Archer, Robert P
Kinetical faceting of the low index W surfaces under electrical current
NASA Astrophysics Data System (ADS)
It's widely accepted that when the scale goes down deeply into nanometer, the surfaces of materials will play a crucial role. In equilibrium, the as-fabricated surfaces are usually determined by Wulff construction. However, the technique to rebuild the surface in the scale of as fine as 1 nm, especially to build the off-equilibrium high energy facets is still rare. Here we provide a simple but effective solution for rebuilding the surfaces on the basis of kinetics over thermodynamics. Our in situ transmission electron microscopy (TEM) experiments demonstrate that the flat surfaces of W naturally decompose into off-equilibrium faceted surfaces when electrical current passes in certain directions. The experiments and simulations confirmed that, by using a polar plot and the data of surface diffusivities, the stability of any kind of surfaces as well as the exact post-treatment structures (surface type and periodical length) can be determined. This technique can be generally extended to most conductive solid surfaces.
Zhao, Jiong; Yu, Rong; Dai, Sheng; Zhu, Jing
NUBEAM as TRANSP parallel service and component for SWIM or FACETS
NASA Astrophysics Data System (ADS)
The PPPL Monte-Carlo module NUBEAM is a package for modeling fast ion species in an axisymmetric tokamak. Since its parallelization in 2006, it has been deployed as part of the TRANSP Parallel Service at PPPL. The recently updated parallel service allows for concurrent running of multiple processes consisting of serial TRANSP client jobs sharing a multi-processor server for the NUBEAM code; performance characteristics of the parallel server will be described in this poster. NUBEAM has also been configured to run simulations for the SWIM project. We have recently performed the first 16-processor TSC/TRANSP simulation of the 200s approach to flattop of an ITER hybrid scenario discharge in the SWIM framework.Currently efforts are underway to incorporate NUBEAM as a formal component in the FACETS and SWIM SciDAC frameworks, coupled through the SWIM Plasma State interface similar to other tokamak heating and current drive models in these projects. This poster will discuss performance scaling, computing/communication costs and physics benefits of parallelized NUBEAM as a component in TRANSP parallel services and SWIM/FACETS.
Indireshkumar, K.; Ku, Long-Poe; McCune, D.; Randerson, L.; Pletzer, A.; Malony, A.; Morris, A.; Shende, S.
Highly exposed {001} facets of titanium dioxide modified with reduced graphene oxide for dopamine sensing.
Titanium dioxide (TiO2) with highly exposed {001} facets was synthesized through a facile solvo-thermal method and its surface was decorated by using reduced graphene oxide (rGO) sheets. The morphology and chemical composition of the prepared rGO/TiO2 {001} nanocomposite were examined by using suitable characterization techniques. The rGO/TiO2 {001} nanocomposite was used to modify glassy carbon electrode (GCE), which showed higher electrocatalytic activity towards the oxidation of dopamine (DA) and ascorbic acid (AA), when compared to unmodified GCE. The differential pulse voltammetric studies revealed good sensitivity and selectivity nature of the rGO/TiO2 {001} nanocomposite modified GCE for the detection of DA in the presence of AA. The modified GCE exhibited a low electrochemical detection limit of 6??M over the linear range of 2-60??M. Overall, this work provides a simple platform for the development of GCE modified with rGO/TiO2 {001} nanocomposite with highly exposed {001} facets for potential electrochemical sensing applications. PMID:24853929
How, Gregory Thien Soon; Pandikumar, Alagarsamy; Ming, Huang Nay; Ngee, Lim Hong
Computed tomography-guided percutaneous facet screw fixation in the lumbar spine. Technical note.
The authors describe a new minimally invasive technique for posterior supplementation using percutaneous translaminar facet screw (TFS) fixation with computed tomography (CT) guidance. Oblique axial images were used to determine facet screw fixation sites. After the induction of local anesthesia and conscious sedation, a guide pin was inserted and guided with a laser mounted on the CT gantry. Cannulated TFSs were placed via a percutaneous approach. From December 2002 to August 2003, 18 patients underwent CT-guided TFS. In 17 of these patients this procedure was supplementary to anterior lumbar interbody fusion, which had been performed several days earlier; in the remaining patient, CT-guided TFS fixation was undertaken as the primary therapy. Twelve patients had painful degenerative disc disease or unstable degenerative spondylolisthesis, three had infections, and three had deformities. All screws were inserted accurately and there were no complications. This new minimally invasive surgical technique may offer an alternative to pedicle screw fixation as a method of posterior supplementation. PMID:17633496
Kang, Ho Yeong; Lee, Sang-Ho; Jeon, Sang Hyeop; Shin, Song-Woo
MgO nano-facet embedded silver-based dielectric/metal/dielectric transparent electrode.
We replace Indium Tin Oxide (ITO) with an MgO nano-facet Embedded WO(3)/Ag/WO(3)(WAW) multilayer for electrodes of high efficiency OLEDs. WAW shows higher values for transmittance (93%) and conductivity (1.3æ10(5) S/cm) than those of ITO. Moreover, WAW shows higher transmittance (92.5%) than that of ITO (86.4%) in the blue region (<500 nm). However, due to the large difference in refractive indices (n) of glass (n=1.55) and WO(3) (n=1.95), the incident light has a small critical angle (52¯). Thus, the generated light is confined by the glass/WAW interface, resulting in low light outcoupling efficiency (~20%). This can be enhanced by using a nano-facet structured MgO (n=1.73) layer and a ZrO(2) (n=1.84) layer as a graded index layer. Using these optimized electrodes, ITO-free, OLEDs with various emission wavelengths have been produced. The luminance of OLEDs using MgO/ZrO(2)/WAW layers is enhanced by 24% compared to that of devices with ITO. PMID:22274430
Kim, Sungjun; Yu, Hak Ki; Hong, Kihyon; Kim, Kisoo; Son, Jun Ho; Lee, Illhwan; Kim, Kyoung-Bo; Kim, Tae-Yeob; Lee, Jong-Lam
Enabling multi-faceted measures of success for protected area management in Trinidad and Tobago.
A key challenge has been to define and measure "success" in managing protected areas. A case study was conducted of efforts to evaluate the new protected area management system in Trinidad and Tobago using a participatory approach. The aim of the case study was to (1) examine whether stakeholder involvement better captures the multi-faceted nature of success and (2) identify the role and influence of various stakeholder groups in this process. An holistic and systematic framework was developed with stakeholder input that facilitated the integration of expert and lay knowledge, a broad emphasis on ecological, socio-economic, and institutional aspects, and the use of both quantitative and qualitative data allowing the evaluation to capture the multi-faceted nature and impacts of protected area management. Input from primary stakeholders, such as local communities, was critical as they have a high stake in protected area outcomes. Secondary and external stakeholders, including government agencies, non-governmental organizations, academia and the private sector, were also important in providing valuable technical assistance and serving as mediators. However, a lack of consensus over priorities, politics, and limited stakeholder capacity and data access pose significant barriers to engaging stakeholders to effectively measure the management success of protected areas. PMID:21555042
Granderson, Ainka A
Delaminated graphene at silicon carbide facets: atomic scale imaging and spectroscopy.
Atomic-resolution structural and spectroscopic characterization techniques (scanning transmission electron microscopy and electron energy loss spectroscopy) are combined with nanoscale electrical measurements (conductive atomic force microscopy) to study at the atomic scale the properties of graphene grown epitaxially through the controlled graphitization of a hexagonal SiC(0001) substrate by high temperature annealing. This growth technique is known to result in a pronounced electron-doping (?10(13) cm(-2)) of graphene, which is thought to originate from an interface carbon buffer layer strongly bound to the substrate. The scanning transmission electron microscopy analysis, carried out at an energy below the knock-on threshold for carbon to ensure no damage is imparted to the film by the electron beam, demonstrates that the buffer layer present on the planar SiC(0001) face delaminates from it on the (112n) facets of SiC surface steps. In addition, electron energy loss spectroscopy reveals that the delaminated layer has a similar electronic configuration to purely sp2-hybridized graphene. These observations are used to explain the local increase of the graphene sheet resistance measured around the surface steps by conductive atomic force microscopy, which we suggest is due to significantly lower substrate-induced doping and a resonant scattering mechanism at the step regions. A first-principles-calibrated theoretical model is proposed to explain the structural instability of the buffer layer on the SiC facets and the resulting delamination. PMID:23530467
Nicotra, Giuseppe; Ramasse, Quentin M; Deretzis, Ioannis; La Magna, Antonino; Spinella, Corrado; Giannazzo, Filippo
Faceting of Nanoscale Pt and Au Particles for Applications in Catalysis
In an effort to reduce the world's dependence on fossil fuels as well as lower green house gas emissions, proton exchange membrane fuel cells (PEMFC) have been considered by many as a prime candidate for both mobile and stationary alternative energy sources. The principal limiting factor for efficiency in fuel cells is the oxygen reduction reaction (ORR) which is driven by platinum based catalyst materials. Numerous methods have been developed to synthesize particles that make more efficient use of the active surfaces by tuning shapes, sizes and facets. For example, it was recently demonstrated that selectivity can be tuned by controlling particle shape in the case of promoting trans olefin isomerization to their cis counterparts using close-packed Pt (111), Pt (557) and Pt (100) surfaces as opposed to a more open Pt (110), which favored the trans-counterparts. Furthermore, it has been reported that certain facets exhibit improved ORR activity while others may decrease activity at the bulk phase single crystal level. Here, we will present a study of various wet chemical reduction methods targeting specific morphologies and the resulting electrochemical activity. Determining the effects of synthetic parameters on the final product via transmission electron microscopy (TEM), small angle x-ray scattering (SAXS) and wide angle x-ray scattering (WAXS) provides mechanistic insight on growth kinetics, while electrochemical studies correlate physical properties to performance. Understanding structure and activity relationships will allow us to intuitively design next generation materials with enhanced properties.
Richards, R. M.; Leong, J.; Dinh, H.; Pivovar, B.
Highly exposed {001} facets of titanium dioxide modified with reduced graphene oxide for dopamine sensing
Titanium dioxide (TiO2) with highly exposed {001} facets was synthesized through a facile solvo-thermal method and its surface was decorated by using reduced graphene oxide (rGO) sheets. The morphology and chemical composition of the prepared rGO/TiO2 {001} nanocomposite were examined by using suitable characterization techniques. The rGO/TiO2 {001} nanocomposite was used to modify glassy carbon electrode (GCE), which showed higher electrocatalytic activity towards the oxidation of dopamine (DA) and ascorbic acid (AA), when compared to unmodified GCE. The differential pulse voltammetric studies revealed good sensitivity and selectivity nature of the rGO/TiO2 {001} nanocomposite modified GCE for the detection of DA in the presence of AA. The modified GCE exhibited a low electrochemical detection limit of 6??M over the linear range of 260??M. Overall, this work provides a simple platform for the development of GCE modified with rGO/TiO2 {001} nanocomposite with highly exposed {001} facets for potential electrochemical sensing applications.
How, Gregory Thien Soon; Pandikumar, Alagarsamy; Ming, Huang Nay; Ngee, Lim Hong
Cellular Pressure-Actuated Joint
NASA Technical Reports Server (NTRS)
A modification of a pressure-actuated joint has been proposed to improve its pressure actuation in such a manner as to reduce the potential for leakage of the pressurizing fluid. The specific joint for which the modification is proposed is a field joint in a reusable solid-fuel rocket motor (RSRM), in which the pressurizing fluid is a mixture of hot combustion gases. The proposed modification could also be applicable to other pressure-actuated joints of similar configuration.
McGuire, John R.
Cleaved laser facets on free-standing InGaN LD membrane created by laser lift-off and structural characterisation of the membrane
Cleaved laser facets on free-standing InGaN laser diode membrane created by laser lift-off were fabricated and studied. Cleaved laser facets on GaN on sapphire have been compared with those on free-standing laser membrane. Atomic force microscopy and scanning electron microscopy results show that the cleaved laser facets on free-standing laser membrane are much smoother than those on sapphire. Transmission electron
Li Zilan; Hu Xiaodong; Qin Zhixin; Yu Tongjun; Nie Ruijuan; Lu Min; Ren Qian; Zhang Bei; Yang Zhijian; Chen Weihua; Chen Zhizhong; Yang Hua; Zhang Guoyi
Double slotted socket spherical joint
A new class of spherical joints is disclosed. These spherical joints are capable of extremely large angular displacements (full cone angles in excess of 270.degree.), while exhibiting no singularities or dead spots in their range of motion. These joints can improve or simplify a wide range of mechanical devices.
Bieg, Lothar F. (Albuquerque, NM); Benavides, Gilbert L. (Albuquerque, NM)
The Challenges of Joint Attention
This paper discusses the concept of joint at- tention and the dierent skills underlying its development. We argue that joint attention is much more than gaze following or simul- taneous looking because it implies a shared intentional relation to the world. The current state-of-the-art in robotic and computational models of the dierent prerequisites of joint attention is discussed in relation
Frederic Kaplan; Verena V. Hafner
Glued joints in hardwood timber
The use of glued joints offers an option with ample aesthetic and functional possibilities in the design of wood structures. This type of joint is used since years 1970 in countries of North and Central Europe, for the design and construction of glulam (glued laminated timber) structures. This has led to diverse investigations in the experimental analysis of joints made
D Otero Chans; J. EstÕvez Cimadevila; E. MartÚn GutiÕrrez
NASA Technical Reports Server (NTRS)
This report consists of inputs from each of the Phase I Program Joint Working Groups. The Working Groups were tasked to describe the organizational structure and work processes that they used during the program, joint accomplishments, lessons learned, and applications to the International Space Station Program. This report is a top-level joint reference document that contains information of interest to both countries.
Nield, George C. (Editor); Vorobiev, Pavel Mikhailovich (Editor)
Preparation of superparamagnetic Mn(x)Fe(1-x)O nanoparticles from low-index-facet cubes to high-index-facet concave structures and their catalytic performance in aqueous solution.
We report the synthesis of concave magnetic Mn(x)Fe(1-x)O nanoparticles with high-index facet structures by a thermal decomposition approach. The particle morphology varies from cubic shape under pure Ar, to star-like shapes with exposure to air during the reaction. The oxidative etching in the presence of air (O2) strongly affects the exposed facets on the surface. These concave nanoparticles are transferred from the organic phase to aqueous solution and show distinct catalytic activity toward the degradation of xylenol orange in aqueous solution. PMID:23836257
Lee, Pei-Ying; Teng, His-Sheng; Yeh, Chen-Sheng
Facet growth of self-separated GaN layers through HVPE on large square-patterned template
NASA Astrophysics Data System (ADS)
A self-separated GaN layer was prepared by hydride vapor phase epitaxy (HVPE) on a square-patterned template with large periodicity. Self-separation was completed by breakage of the fragile layer because of the thermal stresses generated during the cooling process after HVPE growth. The GaN layer exhibited graphical surface comprising the terrace and the concave, the shapes of which were corresponding with the mask pattern. The terrace came from the growth on window openings, and had Ga-polarity by wet etching and micro-Raman measurement. The concave over the mask was composed of large inclined facets, and was demonstrated to have N-polarity. The growth on large square-patterned template was considered to be facet growth. The polarity inversion was related to dislocation accumulation. The strain distribution regularly varied, which was interpreted based on the facet growth mode.
Sui, Yanping; Wang, Bin; Zhao, Zhide; Xu, Wei; Li, Xiaoliang; Wang, Xinzhong; Yu, Guanghui
Multi-facet concentrator of solar setup for irradiating the objects placed in a target plane with solar light
According to the proposed invention, this technical result is achieved so that many-facet concentrator of a solar setup for exposure of objects, placed in a target plane, to the action of solar radiation containing a supporting frame and facets differing by that the facets of the concentrator are chosen with spherical focusing reflective surfaces of equal focal lengths and with selective coatings reflecting a desired spectral fraction of solar radiation, and are arranged on the supporting frame symmetrically with respect to the common axis of the concentrator, their optical axes being directed to the single point on the optical axis of the concentrator located before the nominal focus point of the concentrator and determining the position of arranging the target plane.
Lewandowski, Allan A. (Evergreen, CO); Yampolskiy, Vladislav (Moscow, RU); Alekseev, Valerie (Moscow, RU); Son, Valentin (Moscow, RU)
Summary Background: Despite the fact that joint tuberculosis is one of the most common forms of extrapulmonary tuberculosis, it is a disease entity that is very rare in Poland (less than 100 cases a year in the last 10 years). The symptoms are non-specific, and thus the disease is rarely taken into account in preliminary differential diagnosis. Case Report: A 68-year-old female patient was admitted to the Internal Diseases Clinic due to oedema and pain of the right shoulder joint. The pain has been increasing for about 8 months. Physical examination revealed increased circumference and elevated temperature of the right shoulder joint. Limb function was retained. The full range of radiological and laboratory diagnostic examinations was performed, including the biopsy of the affected tissue which revealed the presence of Mycobacterium tuberculosis in the bacterial culture. Clinical improvement was obtained after introduction of TB drugs. Conclusions: Radiological diagnostic methods (X-ray, CT scans, MRI scans) provide high precision monitoring of articular lesions. However, the decisive diagnosis requires additional laboratory tests as well as histopathological and bacteriological assays.
Ostrowska, Monika; Gietka, Jan; Nesteruk, Tomasz; Piliszek, Agnieszka; Walecki, Jerzy
Ruscoe 983 Joint Sealant: Product Evaluation.
National Technical Information Service (NTIS)
This report contains a product evaluation of Ruscoe's 983 joint sealant. Ruscoe 983 is an asphalt base single compound joint sealant. It contains an aluminum fortified adhesive and is designed for use on highway expansion joints, bridge joints, and random...
S. L. Tritsch T. M. Wolfe
Code of Federal Regulations, 2012 CFR
...The joints. As regards the joints the factors of disability...movement than normal (from flail joint, resections, nonunion of...movements smoothly. (f) Pain on movement, swelling...and ankle are considered major joints; multiple involvements of...
Code of Federal Regulations, 2010 CFR
...The joints. As regards the joints the factors of disability...movement than normal (from flail joint, resections, nonunion of...movements smoothly. (f) Pain on movement, swelling...and ankle are considered major joints; multiple involvements of...
Code of Federal Regulations, 2011 CFR
...The joints. As regards the joints the factors of disability...movement than normal (from flail joint, resections, nonunion of...movements smoothly. (f) Pain on movement, swelling...and ankle are considered major joints; multiple involvements of...
Code of Federal Regulations, 2013 CFR
...Transportation 4 2013-10-01 2013-10-01 false Rail joints. 213.121 Section 213.121 Transportation...SAFETY STANDARDS Track Structure ôÏ 213.121 Rail joints. (a) Each rail joint, insulated joint, and compromise...
Association of NEO personality domains and facets with presence, onset, and treatment outcomes of major depression in older adults
Objectives To assess the relationship of multiple domains and facets of the five factor model of personality with presence, onset, and severity of late life depression. Design Cross-sectional analysis of depression status, and age of onset. Retrospective analysis of baseline severity. Longitudinal analysis of severity after 3 and 12 months of psychiatric treatment. Setting: Private university-affiliated medical center in the Southeastern US. Participants One hundred twelve psychiatric patients with a current episode of unipolar major depression, and 104 nondepressed comparison subjects, ages 60 years and older (mean = 70, SD = 6). Measurements Revised NEO Personality Inventory, Diagnostic Interview Schedule, Montgomery-ésberg Depression Rating Scale. Results Binary logistic regression found that depression was related to higher neuroticism (and all its facets), and to lower extraversion (and facets of assertiveness, activity, and positive emotionality), and conscientiousness (and facets of competence, order, dutifulness, and self-discipline). Multinomial logistic regression found some of these relationships held only for depression with onset before age 50 (hostility, self-consciousness, extraversion, assertiveness, positive emotions, order, and dutifulness). Linear regression found that personality was unrelated to depression severity at the beginning of treatment, but improvement after 3 months was related to lower neuroticism (and facets depressiveness and stress-vulnerability) and higher warmth and competence. Improvement after 12 months was related to lower neuroticism, depressiveness, and stress-vulnerability. Conclusions Specific personality facets are related with depression and treatment outcomes. Screening for certain personality traits at the start of treatment may help identify patients at risk of worse response to treatment after 3 months.
Hayward, R. David; Taylor, Warren D.; Smoski, Moria J.; Steffens, David C.; Payne, Martha E.
Application of combined EBSD and 3D-SEM technique on crystallographic facet analysis of steel at low temperature.
Electron backscatter diffraction has been increasingly used to identify the crystallographic planes and orientation of cleavage facets with respect to the rolling direction in fracture surfaces. The crystallographic indices of cleavage planes can be determined either directly from the fracture surface or indirectly from metallographic sections perpendicular to the plane of the fracture surface. A combination of electron backscatter diffraction and 3D scanning electron microscopy imaging technique has been modified to determine crystallographic facet orientations. The main purpose of this work has been to identify the macroscopic crystallographic orientations of cleavage facets in the fracture surfaces of weld heat affected zones in a well-known steel fractured at low temperatures. The material used for the work was an American Petroleum Institute (API) X80 grade steel developed for applications at low temperatures, and typical heat affected zone microstructures were obtained by carrying out weld thermal simulation. The fracture toughness was measured at different temperatures (0¯C, -30¯C, -60¯C and -90¯C) by using Crack Tip Opening Displacement testing. Fracture surfaces and changes in microstructure were analyzed by scanning electron microscopy and light microscopy. Crystallographic orientations were identified by electron backscatter diffraction, indirectly from a polished section perpendicular to the major fracture surface of the samples. Computer assisted 3D imaging was used to measure the angles between the cleavage facets and the adjacent polished surface, and then these angles were combined with electron backscatter diffraction measurements to determine the macroscopic crystallographic planes of the facets. The crystallographic indices of the macroscopic cleavage facet planes were identified to be {100}, {110}, {211} and {310} at all temperatures. PMID:23692572
Mohseni, P; Solberg, J K; Karlsen, M; Akselsen, O M; Ostby, E
Testing of explosive welding and welded joints: joint mechanism and properties of explosive welded joints
In this study physical mechanism of explosive welding joint was analysed. The mechanism refers to wavy joint with interpass\\u000a and without one. Plastic strain, viscosity and acoustic waves were applied to explain the problem. The own model of the mechanism\\u000a of oxide removal for the direct joint and test results confirming the bonding mechanism were showed.
Bogumil Wronka
Laboratory characterization of rock joints
A laboratory characterization of the Apache Leap tuff joints under cyclic pseudostatic and dynamic loads has been undertaken to obtain a better understanding of dynamic joint shear behavior and to generate a complete data set that can be used for validation of existing rock-joint models. Study has indicated that available methods for determining joint roughness coefficient (JRC) significantly underestimate the roughness coefficient of the Apache Leap tuff joints, that will lead to an underestimation of the joint shear strength. The results of the direct shear tests have indicated that both under cyclic pseudostatic and dynamic loadings the joint resistance upon reverse shearing is smaller than that of forward shearing and the joint dilation resulting from forward shearing recovers during reverse shearing. Within the range of variation of shearing velocity used in these tests, the shearing velocity effect on rock-joint behavior seems to be minor, and no noticeable effect on the peak joint shear strength and the joint shear strength for the reverse shearing is observed.
Hsiung, S.M.; Kana, D.D.; Ahola, M.P.; Chowdhury, A.H.; Ghosh, A. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses
Immunohistochemical study of human costotransverse joints: A preliminary investigation.
The human costotransverse joint (CTJ) is the articulation between the posterior tubercle of the ribs with the first through tenth costal facet of the thoracic transverse processes. While the CTJ is well defined anatomically and considered a synovial joint, the human CTJ as a pain generating structure is controversial and not supported from a histological perspective. The objective of the present study was to investigate the histological pain producing properties of CTJ capsule tissue. Ten micron cross-sections at each level (1-10) were stained with H & E or immunostained with antisera against Substance P (SP), calcitonin-gene-related peptide (CGRP), and neuropeptide Y (NPY). Immunoreactivity was confirmed for SP, CGRP, and NPY within the CTJ tissue samples of two unembalmed male cadavers. The presence of previously mentioned neuropeptides suggests that human CTJ is capable of producing pain through somatic and autonomic nervous systems. Therefore, clinicians should consider the CTJ as a differential diagnostic possibility when examining and treating painful thoracic conditions. PMID:21400610
Dedrick, G S; Sizer, P S; Sawyer, B G; BrismeÒ, J M; Smith, M P
Subfracture insult to a knee joint causes alterations in the bone and in the functional stiffness of overlying cartilage.
The current criteria used by the automotive industry for predicting joint injury are based on fracture of bone, but clinical studies suggest that chronic diseases such as osteoarthrosis can occur from a single blunt insult without bone fracture. In the current study, blunt insults were delivered to the patellofemoral joints of rabbits without producing bone fractures. Biomechanical and histological studies were performed on joint tissues at various times after insult. The functional integrity of the retropatellar cartilage on the lateral facet was measured with mechanical indentation experiments, and the thickness of the subchondral bone was measured from histological sections. Impacts produced surface lesions on the retropatellar cartilage. The thickness of the subchondral bone in representative animals tended to increase with time after insult, and the bone exhibited significant thickening at 12 months. The overlying cartilage showed signs of degeneration. However, the mechanical stiffness of the cartilage did not change until 12 months after the insult. PMID:9246093
Newberry, W N; Zukosky, D K; Haut, R C
Soldering of mild steels: functional joints
In recent years, adhesive joints have replaced numerous soldered joints, especially in applications where electrical conductivity is not required from the members of the joint. Nevertheless, soldered joints are still used in applications ranging from electronics to high-technology components. The present work seeks to demonstrate that soldered joints, which can be considered as functional joints, have very good mechanical properties
F. Molleda; J. Mora; E. Carillo; B. G Mellor
Co3O4 nanocages with highly exposed {110} facets for high-performance lithium storage.
Functional materials with both exposed highly reactive planes and hollow structures have attracted considerable attentions with respect to improved catalytic activity and enhanced electrochemical energy storage. Herein, we report the synthesis of unusual single-crystal Co3O4 nanocages with highly exposed {110} reactive facets via a one-step solution method. When tested as anode materials in lithium-ion batteries, these Co3O4 nanocages deliver a high reversible lithium storage capacity of 864 mAh g(-1) at 0.2C over 50 cycles and exhibit an excellent rate capability. The dominantly exposed {110} planes, a high density of atomic steps in nanocages, and the large void interiors lead to the regarded superior electrochemical performance. PMID:23995848
Liu, Dequan; Wang, Xi; Wang, Xuebin; Tian, Wei; Bando, Yoshio; Golberg, Dmitri
Terahertz quantum well photo-detectors: grating versus 45¯ facet coupling
NASA Astrophysics Data System (ADS)
We demonstrate two GaAs/AlGaAs-based terahertz (THz) quantum well photo-detectors (QWPs), with one-dimensional (1D) metal grating and 45¯ facet light coupling configurations. The two THz QWPs have the same multi-quantum well structure parameters. The different light coupling configurations do not affect the peak response frequency (5.85 THz). The background limited infrared performance temperatures and responsivities of the two devices are measured. The effects of different light coupling configurations on the main features of the devices are investigated in detail. The experimental results show that the performance of the THz QWP with 1D metal grating is a little better but there is still a lot of room for improvement.
Gu, L. L.; Zhang, R.; Tan, Z. Y.; Wan, W. J.; Yin, R.; Guo, X. G.; Cao, J. C.
On the facet-skeletal transition of snow crystals - Experiments in high and low gravity
NASA Astrophysics Data System (ADS)
A laboratory investigation of the influence of air velocity on the growth of columnar ice crystals from the vapor over the range -3 to -5 C shows that the linear growth velocity increases and that columns transform to sheath crystals or needles as air velocity increases from a few cm/s to 40 cm/s. Comparison with a similar transition of plates to dendrites shows that, macroscopically, in both cases the facets sprout rounded tips at a critical velocity which is lower for higher ambient supersaturation. Studies in low gravity show that chamber scale convection under normal gravity may have significant influence on growth even in the absence of an imposed air velocity. Falling snow crystals become more skeletal in shape as they grow and fall with increasing velocity. This development depends critically on temperature (+ or - 0.5 C) and demonstrates that the snow crystal shape is even more dependent on environmental growth conditions that previously thought.
Alena, T.; Hallett, J.; Saunders, C. P. R.
Co3O4 nanocages with highly exposed {110} facets for high-performance lithium storage
Functional materials with both exposed highly reactive planes and hollow structures have attracted considerable attentions with respect to improved catalytic activity and enhanced electrochemical energy storage. Herein, we report the synthesis of unusual single-crystal Co3O4 nanocages with highly exposed {110} reactive facets via a one-step solution method. When tested as anode materials in lithium-ion batteries, these Co3O4 nanocages deliver a high reversible lithium storage capacity of 864?mAh g?1 at 0.2C over 50 cycles and exhibit an excellent rate capability. The dominantly exposed {110} planes, a high density of atomic steps in nanocages, and the large void interiors lead to the regarded superior electrochemical performance.
Liu, Dequan; Wang, Xi; Wang, Xuebin; Tian, Wei; Bando, Yoshio; Golberg, Dmitri
Hidden surface states at non-polar GaN (1010) facets: Intrinsic pinning of nanowires
NASA Astrophysics Data System (ADS)
We investigate the electronic structure of the GaN(1010) prototype surface for GaN nanowire sidewalls. We find a paradoxical situation that a surface state at all k points in the bandgap cannot be probed by conventional scanning tunneling microscopy, due to a dispersion characterized by a steep minimum with low density of states (DOS) and an extremely flat maximum with high DOS. Based on an analysis of the decay behavior into the vacuum, we identify experimentally the surface state minimum 0.6 +/- 0.2 eV below the bulk conduction band in the gap. Hence, GaN nanowires with clean (1010) sidewall facets are intrinsically pinned.
Lymperakis, L.; Weidlich, P. H.; Eisele, H.; Schnedler, M.; Nys, J.-P.; Grandidier, B.; StiÕvenard, D.; Dunin-Borkowski, R. E.; Neugebauer, J.; Ebert, Ph.
Facet dependent reactivity and selective deposition of nanometer sized {beta}-SiC on diamond surfaces
Selective deposition of nano-{beta}-SiC on non-(100) diamond faces has been observed in a microwave plasma chemical vapor deposition process due to the presence of Si(CH{sub 3}){sub 4} in the gas phase. The process allows only the growth of diamond starting crystals whose [001] is normal to the film surface and interrupts the growth of otherwise oriented grains; this is due to the preferential deposition of SiH{sub 3} on (111) diamond but not on (001) diamond according to additional theoretical reactivity analysis of the gas species on the exposed diamond surfaces. The facet dependent reactivity facilitates control of diamond/{beta}-SiC nanocomposite film growth.
Jiang, X.; Srikanth, V. V. S. S. [Institute of Materials Engineering, University of Siegen, Paul-Bonatz-Str. 9-11, 57076 Siegen (Germany); Zhao, Y. L. [Institute of Material Science and Engineering, Ocean University of China, Qingdao 266100 (China); Zhang, R. Q. [Centre of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China)
Introducing FACETS, the Framework Application for Core-Edge Transport Simulations
The FACETS (Framework Application for Core-Edge Transport Simulations) project began in January 2007 with the goal of providing core to wall transport modeling of a tokamak fusion reactor. This involves coupling previously separate computations for the core, edge, and wall regions. Such a coupling is primarily through connection regions of lower dimensionality. The project has started developing a component-based coupling framework to bring together models for each of these regions. In the first year, the core model will be a 1 dimensional model (1D transport across flux surfaces coupled to a 2D equilibrium) with fixed equilibrium. The initial edge model will be the fluid model, UEDGE, but inclusion of kinetic models is planned for the out years. The project also has an embedded Scientific Application Partnership that is examining embedding a full-scale turbulence model for obtaining the crosssurface fluxes into a core transport code.
Cary, John R. [Tech-X Corporation; Candy, Jeff [General Atomics; Cohen, Ronald H. [Lawrence Livermore National Laboratory (LLNL); Krasheninnikov, Sergei I [ORNL; McCune, Douglas C [ORNL; Estep, Donald J [Colorado State University, Fort Collins; Larson, Jay W [ORNL; Malony, Allen [University of Oregon; Worley, Patrick H [ORNL; Carlsson, Johann Anders [ORNL; Hakim, A H [Tech-X Corporation; Hamill, P [Tech-X Corporation; Kruger, Scott E [ORNL; Muzsala, S [Tech-X Corporation; Pletzer, Alexander [ORNL; Shasharina, Svetlana [Tech-X Corporation; Wade-Stein, D [Tech-X Corporation; Wang, N [Tech-X Corporation; McInnes, Lois C [ORNL; Wildey, T [Tech-X Corporation; Casper, T. A. [Lawrence Livermore National Laboratory (LLNL); Diachin, Lori A [ORNL; Epperly, Thomas [Lawrence Livermore National Laboratory (LLNL); Rognlien, T. D. [Lawrence Livermore National Laboratory (LLNL); Fahey, Mark R [ORNL; Kuehn, Jeffery A [ORNL; Morris, A [University of Oregon; Shende, Sameer [University of Oregon; Feibush, E [Tech-X Corporation; Hammett, Gregory W [ORNL; Indireshkumar, K [Tech-X Corporation; Ludescher, C [Tech-X Corporation; Randerson, L [Tech-X Corporation; Stotler, D. [Princeton Plasma Physics Laboratory (PPPL); Pigarov, A [University of California, San Diego; Bonoli, P. [Massachusetts Institute of Technology (MIT); Chang, C S [New York University; D'Ippolito, D. A. [Lodestar Research Corporation; Colella, Philip [Lawrence Berkeley National Laboratory (LBNL); Keyes, David E [Columbia University; Bramley, R [Indiana University; Myra, J. R. [Lodestar Research Corporation
Anomalies in modeling of anisotropic etching of silicon: Facet boundary effects
NASA Astrophysics Data System (ADS)
Beginning with an idealized model of anisotropic etching of silicon in which the etch behavior depends only on the crystal features presented to the etchant, this article extends the model to address certain anomalies observed in the data. The idealized model is based on profiles of underetched surfaces and underetch behavior as a function of mask-edge deviation in wagon-wheel experiments on Si{110} and Si{100} at different TMAH concentrations. Underetched surfaces are found to follow a cohesive system composed of planes defined by two types of crystal features: periodic bond chains and rows of kinks. But it is also found that the same crystal planes in the same etchant often exhibit different etch rates. These anomalies are outlined, and interactions at the boundaries between adjacent facets are proposed to explain them.
Elalamy, Z.; Landsberger, L. M.; Pandy, A.; Kahrizi, M.; Stateikina, I.; Michel, S.
Magnetic Resonance Imaging in Cervical Facet Dislocation: A Third World Perspective
Study Design Retrospective case series. Purpose The objective of our study was to determine the change in management brought about by magnetic resonance imaging (MRI) of the cervical spine in alert and awake patients with facet dislocation and spinal cord injury presenting within 4 hours after injury. Overview of Literature Spinal cord injury is a common clinical entity. The role of MRI is well established in evaluating spinal trauma. However, the time at which MRI should be used is still controversial. Methods Retrospective data from 2002-2010 was evaluated. All of the alert and awake patients with spinal cord injury, based on clinical examination with facet dislocation diagnosed on lateral cervical spine X-rays, were included. A questionnaire was also conducted, the data of which consisted of demographic details including age and sex, the mechanism of injury, clinical examination, X-ray findings, MRI findings, whether or not surgery was performed and the time elapsed since injury. Data was analyzed using SPSS ver. 17.0. Continuous variables such as age were expressed in terms of mean Ý standard deviation. Categorical variables such as change in management, X-ray/MRI findings and neurological motor level were assessed in terms of percentage. Results Fifty patients participated in our study. All these patients had spinal cord injury with defined motor levels. The mean age was 35.5 Ý 8.95 years (range, 20 to 52 years). Fifty percent showed a motor level at C6 level. None of the patients required any change in management based on the MRI. Conclusions MRI of the spine in awake patients within 4 hours after injury does not change the management of patients. However, we can hypothesize that such patients can proceed to traction without waiting for the MRI.
Nasir, Sadaf; Murtaza, Ghulam; Moeed, Umber; Bari, Muhammad Ehsan
Preparation of superparamagnetic MnxFe1-xO nanoparticles from low-index-facet cubes to high-index-facet concave structures and their catalytic performance in aqueous solution
NASA Astrophysics Data System (ADS)
We report the synthesis of concave magnetic MnxFe1-xO nanoparticles with high-index facet structures by a thermal decomposition approach. The particle morphology varies from cubic shape under pure Ar, to star-like shapes with exposure to air during the reaction. The oxidative etching in the presence of air (O2) strongly affects the exposed facets on the surface. These concave nanoparticles are transferred from the organic phase to aqueous solution and show distinct catalytic activity toward the degradation of xylenol orange in aqueous solution.We report the synthesis of concave magnetic MnxFe1-xO nanoparticles with high-index facet structures by a thermal decomposition approach. The particle morphology varies from cubic shape under pure Ar, to star-like shapes with exposure to air during the reaction. The oxidative etching in the presence of air (O2) strongly affects the exposed facets on the surface. These concave nanoparticles are transferred from the organic phase to aqueous solution and show distinct catalytic activity toward the degradation of xylenol orange in aqueous solution. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr01865b
Lee, Pei-Ying; Teng, His-Sheng; Yeh, Chen-Sheng
Bladder operated robotic joint
NASA Technical Reports Server (NTRS)
This invention is a robotic joint which is operated by inflatable bladders and which can be used in applications where it is desired to move or hold an object. A support block supports an elongated plate to which is pivotally attached a finger. A tension strip passes over a lever attached to the finger and is attached at its ends to the support block on opposite sides of the plate. Bladders positioned between the plate and the tension strip on opposite sides of the plate can be inflated by pumps to pivot the finger, with one of the bladders being inflated while the other is being deflated.
Robertson, Glen A. (inventor)
Tarsometatarsal/Lisfranc joint.
Accurate early diagnosis with adequate reduction and maintenance of anatomic alignment of the dislocation or fracture within the Lisfranc joint complex have been found to be the key to successful outcomes regarding this injury. Because of the anatomic variations, the thin soft tissue envelop, and the abundance of ligamentous and capsular structures in the region, repair of these injuries can be a challenge. The classification systems used to describe these injuries aid in describing the mechanism of injury or displacement type present, which may aid in determining what treatment modality can provide the best outcome. PMID:22424486
DiDomenico, Lawrence A; Cross, Davi
Integrating five-factor model facet-level traits with the theory of planned behavior and exercise
ObjectivesThe purpose of this study was to examine direct, indirect, and moderating links between facet-level personality traits of the five-factor model, the theory of planned behavior (TPB) constructs [Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50, 179211.], and exercise behavior.
Amy L. Hoyt; Ryan E. Rhodes; Heather A. Hausenblas; Peter R. Giacobbi Jr.
Applying the Many-Facet Rasch Model to Evaluate PowerPoint Presentation Performance in Higher Education
ERIC Educational Resources Information Center
This study investigated the usefulness of the many-facet Rasch model (MFRM) in evaluating the quality of performance related to PowerPoint presentations in higher education. The Rasch Model utilizes item response theory stating that the probability of a correct response to a test item/task depends largely on a single parameter, the ability of the
Basturk, Ramazan
Psychometric Properties of the Five Facets Mindfulness Questionnaire (FFMQ) in a Meditating and a Non-Meditating Sample
ERIC Educational Resources Information Center
The factor structure, internal consistency, construct validity, and predictive validity of the Dutch version of the Five Facet Mindfulness Questionnaire (FFMQ-NL) were studied in a sample of meditators (n = 288) and nonmeditators (n = 451). A five-factor structure was demonstrated in both samples, and the FFMQ-NL and its subscales were shown to
de Bruin, Esther I.; Topper, Maurice; Muskens, Jan G. A. M.; Bogels, Susan M.; Kamphuis, Jan H.
Job Satisfaction of Female and Male Superintendents: The Influence of Job Facets and Contextual Variables as Potential Predictors
ERIC Educational Resources Information Center
A descriptive multiple regression approach was used to assess the job satisfaction of female and male public school superintendents taking part in a decennial survey conducted by AASA. Self-reported job satisfaction of public school superintendents was regressed on their affective reactions to specific job facets (supervision, co-workers, and
Young, I. Phillip; Kowalski, Theodore J.; McCord, Robert S.; Petersen, George J.
Essential facets of competence that enable trust in medical graduates: a ranking study among physician educators in two countries.
One way to operationalize the assessment of trainees in a competency-based context is to determine whether they can be entrusted with critical activities. To determine which facets of competence (FOCs) are most informative for such decisions, we performed a Delphi study among Dutch educators. In the current study, the resulting list of facets of competence was evaluated among experienced Dutch and German clinical educators to determine which facets appear most relevant and to evaluate the agreement among experts in different countries as a support for their external validity. Eight Dutch and eight German experts scored each FOC on a five-point scale for relevance. A rank-order comparison showed that there was almost full agreement about the top 10 FOCs, among which 'Scientific and empirical grounded method of working', 'Knowing and maintaining own personal bounds and possibilities', 'Active professional development', 'Teamwork and collegiality', 'Active listening to patients', and 'Verbal communication with colleagues and supervisors'. We conclude that these facets of competence may be used in a training for educators who need to make entrustment decisions about trainees. PMID:24142879
Wijnen-Meijer, Marjo; van der Schaaf, Marieke; Nillesen, Kirstin; Harendza, Sigrid; Ten Cate, Olle
Analysis and design of a concave diffraction grating with total-internal-reflection facets by a hybrid diffraction method.
A novel hybrid diffraction method is introduced to simulate the diffraction and imaging of a planar-integrated concave grating that has total internal reflection (TIR) facets. The Kirchhoff-Huygens diffraction formu