Sharing data among collaborators in widely distributed systems remains a challenge due to limitations with existing methods for defining groups across administrative domain boundaries with various file systems. Groups in traditional systems are bound to particular domains or file systems using centralized storage locations either beyond ordinary users' ability to manage, inaccessible outside a closed system, or both. We present a method for users to independently create and manage groups on any networked workstation using global user identities and to control access to shared data and storage resources based on group membership, regardless of domain boundaries or underlying file systems. Decentralized groups are decoupled from shared user databases and centralized authentication servers through the use of a virtual user namespace. We describe how owners of shared resources can define security policies through the use of caching, and demonstrate how each caching policy represents tradeoffs between performance, scalability, and consistency


Background: This study aimed to compare and evaluate the spatial and statistical models to predict PM2.5 concentrations at ground level and at the macro scale in Mashhad. Methods: To investigate the status of air pollution in the metropolis of Mashhad air, three interpolating models including Ordinary Kriging (OK), Universal Kriging (UK) and inverse distance weighting (IDW) were used. Root Mean Square Error (RMSE) and correlation coefficient (R2) were employed to compare three models and choose the best one. As well as to select the most optimal conditions for the implementation of both OK and UK, used from Standardized RMSE. Results: The results showed that the highest monthly average of PM2.5 was belonged to September and "Sakhteman" station (95.1 μg/m3). Also, the lowest monthly average pollution had happened in "Torogh" station, in November (15.5 μg/m3). According to the data, the OK had the lowest RMSE (10.601) compared to the UK and IDW. Lower RMSE represents lower error between the predicted and measured values. So, OK model selected as better one in interpolation. Also, Judging by correlation coefficient (R2), the highest correlation belonged to OK compared to other two models. UK model showed a greater standard error of predicts than OK. The greatest standard errors of prediction were related to areas that have more distance from air pollution monitoring stations. Conclusion: it should be noted that the production and use of geo-referenced maps could quickly provide spatial analyses, and because it can be combined with GIS, the user is able to investigate the influence the various concentrations of contaminants.


Four species of Nematomorpha are recorded from NE Spain, representing the first reliable data on the group in the Iberian peninsula. Gordius aquations Linnaeus, 1758, G. plicatulus Heinze, 1937, Gordionus wolterstorffii (Camerano, 1888) and Paragordius tricuspidatus (Dufour, 1828) are redescribed based on scanning electron microscope observations. Notes on intraspecific morphological variation and ecology of the species are given.


Purpose of review To provide an overview of the available evidence on the role of the different methods in laparoscopic training, and to summarize the results obtained with standardized training programmes in advanced laparoscopic gynaecological surgery. Recent findings Box trainers as well as virtual reality simulators ensure a benefit in terms of surgical skills development. No data are available showing superiority of one method compared to another. Global Operative Assessment of Laparoscopic Skills (GOALS) remains the most widely used and established scoring system to assess the acquired laparoscopic abilities, also in the field of advanced gynaecological surgery. Standardized training programmes have been recognized as reliable tools able to improve the development of surgical skills, particularly for innovative surgical techniques, such as laparoscopic endoscopic single-site surgery. Summary The traditional approach based on observing and assisting needs to be updated incorporating box trainers and virtual reality simulators. The development of innovative training methods, integrating box trainers and virtual reality simulators, represents the future horizon. All tertiary centres involved in advanced laparoscopic gynaecological surgery should contribute to the development of an integrated network of standardized training programmes, in order to ensure a high-quality laparoscopic training to gynaecologists.


High-precision photometry of solar-like members of the open cluster M67 with Kepler/K2 data has recently revealed enhanced activity for stars with a large Rossby number, which is the ratio of rotation period to the convective turnover time. Contrary to the well established behavior for shorter rotation periods and smaller Rossby numbers, the chromospheric activity of the more slowly rotating stars of M67 was found to increase with increasing Rossby number. Such behavior has never been reported before, although it was theoretically predicted to emerge as a consequence of antisolar differential rotation (DR) for stars with Rossby numbers larger than that of the Sun, because in those models the absolute value of the DR was found to exceed that for solar-like DR. Using gyrochronological relations and an approximate age of 4 Gyr for the members of M67, we compare with computed rotation rates using just the B − V color. The resulting rotation–activity relation is found to be compatible with that obtained by employing the measured rotation rate. This provides additional support for the unconventional enhancement of activity at comparatively low rotation rates and the possible presence of antisolar differential rotation.


Routine characterisation of activated sludge and identification of the filamentous population by microscopic and/or other non-culture dependent techniques can assist in diagnosing the aetiology of poor performance of wastewater treatment works (WWTWs). In South Africa, most facilities rely solely on physicochemical indicators, treating reactors as 'black-boxes', with the result that process adjustments are often delayed, to the detriment of the environment. This study was performed in order to gain insight into the filamentous population found in activated sludge in Cape Town WWTWs, to compare these with other global and local literature findings, and to build capacity in this science. Physicochemical and plant performance parameters, in terms of nutrient removal and settling, were obtained from routine operational data and assessed in conjunction with the microscopic analyses of activated sludge samples taken over a 6-month period. Hypotheses on the links between filament types and/or plant  configurations and/or operational parameters were formulated using  existing literature. In order of prevalence, the five most common dominant filament species in 96 activated sludge samples were: Eikelboom Type  0092, Eikelboom Type 1851, nocardioforms, Microthrix parvicella and  Eikelboom Type 021N. In order to compile a statistically significant  database, it is recommended that an extensive nationwide study is  conducted to link filament types with plant configurations, operational parameters and geographical locations. Keywords : activated sludge, bulking, identification, filament, Type 0092


High saturated fat diets have been shown to raise blood levels of cholecystokinin (CCK) and induce nonalcoholic steatohepatitis (NASH). CCK receptors are expressed on stellate cells and are responsible for hepatic fibrosis when activated. The purpose of this study was to test the safety and dose of a CCK receptor antagonist, proglumide, in human participants with NASH. An open‐label single ascending dose study was conducted in 18 participants with clinical NASH based upon steatosis by liver ultrasound, elevated hepatic transaminases, and a component of the metabolic syndrome. Three separate cohorts (N = 6 each) were treated with oral proglumide for 12 weeks in a sequential ascending fashion with 800 (Cohort 1), 1,200 (Cohort 2), and 1,600 (Cohort 3) mg/day, respectively. Blood hematology, chemistries, proglumide levels, a biomarker panel for fibrosis, and symptom surveys were determined at baseline and every 4 weeks. Abdominal ultrasounds and transient elastography utilizing FibroScan were obtained at baseline and at Week 12. Proglumide was well tolerated at all doses without any serious adverse events. There was no change in body weight from baseline to Week 12. For Cohorts 1, 2, and 3, the median percent change in alanine aminotransferase was 8.42, −5.05, and −22.23 and median percent change in fibrosis score by FibroScan was 8.13, −5.44, and −28.87 (kPa), respectively. Hepatic steatosis as measured by controlled attenuation parameter score significantly decreased with proglumide, (P < 0.05). Blood microRNA biomarkers and serum 4‐hydroxyproline were consistent with decreased fibrosis at Week 12 compared with baseline. These findings suggest proglumide exhibits anti‐inflammatory and anti‐fibrotic properties and this compound is well tolerated in participants with NASH.


Stakeholder involvement is pivotal EU governance. In this paper, we complete a stakeholder analysis of the European Chemicals Agency's recent Annex XV restriction proposal process on intentionally added microplastics. The aim of this study is to map the interests, influence and importance of active stakeholders in order to understand the arguments being put forward by different stakeholders and provide recommendations to policy-makers on how to ensure a balanced consideration of all stakeholder perspectives. Stakeholders were identified through niche media analysis and by scrutinising comments from the public consultation on the restriction proposal. Their importance and influence were mapped using three approaches: "scale from low to high", "psychometric scale" and "qualitative ranking". We identified 205 different stakeholders out of which 77 were industry and trade associations, 25 were large companies and only four were small and medium-sized enterprises. National authorities and researchers did not comment on the restriction proposal, whilst large companies were very active providing comments. Industry trade associations and sports-related non-governmental organizations articulated anxiety about the costs associated with the implementation of the restriction proposal. Among environmental non-governmental organizations, there was consensus that plastics should be handled like other substances under EU's chemical regulation. Primary stakeholders identified exhibited high importance, but varying degrees of influence, while the opposite applied to the major European institutions. Based on our analysis, we recommend that: The European Chemicals Agency implement measures to include "silent" stakeholders and invite guest experts to participate in their committees on Risk Assessment and Socio-Economic Analysis; Researchers should be more active in the public consultation; and that special emphasis should be put on helping small and medium-sized enterprises. With regards to stakeholder consultation, we find that media analysis is a good supplement to stakeholder analysis and that a more objective top-down measure of stakeholder importance and influence is needed.


Abstract : The North Korean attacks on the South Korean naval vessel, the Cheonan, and on the South Korean island of Yeonpyeong in 2010 have resulted in the deterioration of the relationship between North and South Korea. The death of Kim Jong Il in December 2011 has raised serious concerns over the future of North Korea and political stability on the Korean Peninsula. Against this background, South Korea has continued its agenda of military reform to improve the retention and management of its military personnel. However, South Korea needs better methods and measures for evaluating its personnel to distinguish highly qualified officers from less qualified officers. The purpose of this research is to improve the South Korean Army's method of assessing officers through the use of Decision Analysis principles, especially Value-Focused Thinking. The value model was developed to select officers for long-term retention in the Korean Army. The model should serve as an aid to decision makers who will retain the best officers in the Korean Army based on their abilities.


The unified modeling language (UML) is widely used to describe the behavior of systems. It provides a suitable framework for requirements elicitation by means of Use Case diagrams, for functional specifications by means of Interaction diagrams (Sequence diagrams, Collaboration diagram or Communication diagrams) and for behavioral specification by means of Statechart (State-Transition diagrams). It has attracted the attention of researchers interested in automatically deriving the behavior of the components of a system from their interactions. UML lacks a formal semantics and does not propose semantic links between the diagrams of dynamics. In particular, Interaction diagrams do not have an operational semantics describing formally how to carry out such diagrams. Therefore, it is not possible to apply formal techniques for deriving Statecharts from Sequence diagrams. To reach this goal, this paper proposes a new semantics for UML Sequence diagrams based on a relation of causality between the actions of emission and reception of messages. This semantics avoids unnecessary scheduling constraints and so ease the elaboration of high level specifications.


Over the last several decades, there has been a widespread decrease in civic engagement coinciding with a breakdown in traditional family structures in many countries throughout the developed world. According to Putnam in Bowling alone (2000), however, none of the major declines in civic engagement can be accounted for by the decline in traditional family structures. In this paper, we seek to contribute a robust picture of how adult civic engagement is affected by growing up in a non-intact family. Using 26 waves of annual longitudinal data from the German Socio-Economic Panel, we construct various measures of family structure during childhood, and perform both cross-sectional and sibling difference analyses for different indicators of young adults' civic engagement. Both exercises reveal a significant negative relationship between growing up in a non-intact family and children's civic, social and political engagement as adults. We argue that this finding is consistent with causation rather than selection as the explanation for the negative relationship, and provide several robustness checks to support this claim. JEL Classification: J120


Abstract Objective: This study aimed to estimate the association between tobacco smoking and risk for dementia in seven low- and middle-income countries. Methods: Secondary analysis of the 10/66 population-based cohort study was conducted with 11,143 dementia-free individuals aged 65 years and older who were followed-up for an average of 3.8 years totalling 42,715 person-years. Cox regression with competing-risk analyses was used, controlling for age, gender, number of assets, past hazardous drinking, exercise and self-report of heart disease. Exposure was measured in packyears and smoking status. The number of packyears was calculated by multiplying the average number of packs per day by years of consumption up to 50 years old and up to age at baseline. Results: Meta-analysis of the results from each country yielded non-significant pooled relative risk ratios for all comparisons. There was no difference in risk for any dementia between 'ever smokers' compared to 'never smokers' (HR 0.96; 95% CI 0.82–1.13); 'current smokers' compared to 'never smokers' (HR 0.83; 95% CI 0.66–1.06); 'former smokers' compared to 'never smokers' (HR 1.06; 95% CI 0.88–1.27); 'current smokers' compared to 'former smokers' (HR 0.86; 95% CI 0.66–1.13). Results were similar for Alzheimer's disease (AD) and Vascular Dementia (VaD) as outcomes. Lifetime tobacco consumption (packyears) was not associated with any dementia (HR 1.00; 95% CI 0.99–1.00), nor with AD or VaD. Conclusion: Pooled results from all the countries showed no significant association between smoking and the onset of any dementia. Selective quitting in later-life might have biased the results towards no effect.


Alon and Shikhelman [J. Comb. Theory, B. 121 (2016)] initiated the systematic study of the following generalized Turán problem: for fixed graphs H and F and an integer n, what is the maximum number of copies of H in an n-vertex F-free graph?
An edge-colored graph is called rainbow if all its edges have different colors. The rainbow Turán number of F is defined as the maximum number of edges in a properly edge-colored graph on n vertices with no rainbow copy of F. The study of rainbow Turán problems was initiated by Keevash, Mubayi, Sudakov and Verstraete [Comb. Probab. Comput. 16 (2007)].
Motivated by the above problems, we study the following problem: What is the maximum number of copies of F in a properly edge-colored graph on n vertices without a rainbow copy of F? We establish several results, including when F is a path, cycle or tree.


Biomarkers are measurable substances in an organism that are indicative of some phenomenon. Examples of biomarkers in clinical settings are body temperature and blood pressure. Body temperature is indicative of a fever while blood pressure can be used to monitor someone's risk of a stroke. Previous studies have investigated the possibility of there being a potential biomarker for glaucoma. One possible biomarker identified is growth differentiation factor 15 or GDF15. These studies prompted a study in our lab using a rat glaucoma model. The objective of this study was to show there is a biomarker present for the neurodegenerative disease, glaucoma. To mimic the effects of glaucoma, adult healthy rats were anesthetized using a KAX solution, and NaCl was injected into the episcleral veins of experimental eyes to induce scarring in the trabecular meshwork and induce glaucoma-like conditions. In each animal, only one eye was subjected to this procedure. The other eye was left untreated and acted as an internal control. After a specific period of time, the rats were euthanized, and their retinas and aqueous humor were removed. The retinas and aqueous humor from untreated control eyes and from experimental eyes were quantified for GDF15 protein levels using an enzyme-linked immunosorbent assay (ELISA). After quantifying protein expression in both sets of eyes, a separate experiment was done by adding neuroprotective to the experimental eye to see if it had any effect on the GDF15 expression. Previous studies have found that activation of alpha 7 nicotinic acetylcholine receptors, α7nAChRs, in the eye reduces retinal ganglion cell death associated with glaucoma. The neuroprotective used in this study was PNU-282987. PNU-282987 was added to untreated and experimental eyes to determine if its effect on GDF15 protein expression. It was found that there was an increase in GDF15 expression after injection with hypertonic saline. This increase was most prevalent at 3 days and 7 days post operation. This increase means that GDF15 is a potential biomarker for glaucoma. The results from the neuroprotective experiment yielded promising results. There was no significant difference between the eyes treated with PNU-282987, the eyes not treated with PNU-282987, and the control eyes. This result suggests that the neuroprotection worked in preventing the expression of GDF15. The results also showed possible cross over between the eyes since the untreated eyes that had been induced with glaucoma-like conditions also showed no significant difference. To know for sure more experiments need to be done. An early glaucoma marker such as GDF15 levels could help lead to a faster diagnosis in those affected and help us gain a better understanding of the disease itself.


Objectives: (1) To assess innate ex vivo production of interleukin 1β (IL1β) and interleukin 1 receptor antagonist (IL1Ra) in patients with recent-onset rheumatoid arthritis (RA) as compared with healthy controls; (2) to assess the association of ex vivo IL1β and IL1Ra production with progression of joint damage in RA; (3) to determine whether differences in ex vivo IL1β production are explained by distribution of the IL1β single nucleotide polymorphism C-511T. Methods: Levels of IL1β and IL1Ra (measured by ELISA after whole-blood stimulation with lipopolysaccharide) and distribution of IL1β C-511T were compared in 76 patients with recent-onset RA who had received no disease-modifying antirheumatic drugs (DMARDs), and 63 healthy controls. ORs for RA based on ex vivo IL1β and IL1Ra production were calculated. Association of ex vivo IL1β and IL1Ra production with progression of joint damage (Sharp–van der Heijde score over 2 years) was determined by linear regression with correction for baseline characteristics. Results: Patients with recent-onset RA showed lower ex vivo IL1β and higher ex vivo IL1Ra production than healthy controls (p<0.001), with ORs for RA of 2.4 (95% CI 1.2 to 4.9) for low IL1β-producers and 7.6 (95% CI 3.2 to 18.0) for high IL1Ra-producers. High ex vivo IL1Ra production was associated with progression of joint damage (p = 0.01). The IL1β C-511T genotype distribution was not significantly different between patients and controls. Conclusions: Patients with recent-onset RA had decreased ex vivo IL1β production and increased ex vivo IL1Ra production compared with controls. Ex vivo IL1Ra production is an independent predictor of progression of joint damage in recent-onset RA.


Introduction: When performing fetal biometry measurements, the examiner occasionally has the impression that the sonographic estimation is less accurate due to technical limitations. Our objective was to evaluate the possible association between the examiners assessment of the measurement accuracy and the actual error between fetal weight estimation and actual birth weight. Methods: 186 women, within 10 days of delivery, were examined prospectively using fetal biometric measurements. Fetal weight estimates were calculated using Hadlock's formula employing FL, AC and BPD. The sonographers were asked to give a subjective score to each measurement; one point if the quality of the measurement was technically good, two points if the measurement was of medium quality and three points if the measurement was of poor quality. The difference between the corrected sonographic fetal weight estimation and the actual birth weight was analyzed with respect to the scoring given by the examiner. Results: As shown in tables 1–3 for none of the three measured parameters did the perceived measurement accuracy predict the actual error in predicting birth weight.


Multiple myeloma (MM) is associated with a significant risk of infection due to immune dysfunction. Infections are a major cause of morbidity and mortality in MM patients. There are few data available regarding the prevalence of infection in MM patients, especially in conjunction with newer generations of immunomodulatory drugs (thalidomide, bortezomib, lenalidomide) or post autologous stem cell transplantation (ASCT). Intravenous immunoglobulin (IVIG) has been used successfully to reduce infection rates in the stable phase of MM, with limited data in other stages. We retrospectively analyzed 47 patients with MM from March 2006 to June 2009 at our institution. All patients received thalidomide and steroid therapy for at least 6 months. Nine patients received bortezomib and 11 lenalidomide subsequent to thalidomide, because of disease progression, and 22 patients underwent ASCT. The median age was 64 years (range 37–86), with a female–to-male ratio of 18:29. The median residual-serum IgG-level at time of infection was 3.2 g/L, IgA 0.3 g/L and IgM 0.2 g/L. Most patients suffered from recurrent moderate to severe bacterial infections, including the ASCT group. Fifteen patients suffered from different degrees of viral infections. All patients except 3 received IVIG therapy with a significant decline of the rate of infection thereafter (p<001). Our analysis shows that patients with MM treated with the new immunomodulatory drugs in conjunction with steroids are at significant increased risk of infection. Employing IVIG therapy appears to be an effective strategy to prevent infection in this cohort of patients. Further studies to confirm these findings are warranted.


A framework for building network-based EDM CAPP system using intelligent technology to support organizations characterized by physically distributed, enterprise-wide, heterogeneous intelligent manufacturing system over Internet is proposed. Expert system theory is introduced. Rule-Based reasoning and Case-Based reasoning method are introduced to reason EDM method. Genetic Algorithm is applied to optimize EDM technological parameter. Fuzzy reasoning algorithm is applied to select technological data. Artificial Neural Network is applied to forecast technological effect. Internet environment and Technological knowledge database modules are introduced. Instances are also introduced to testify feasibility.


A new method for optimal control design of distributed parameter systems is presented in this paper. The concept of proper orthogonal decomposition is used for the model reduction of distributed parameter systems to form a reduced order lumped parameter problem. The optimal control problem is then solved in the time domain, in a state feedback sense, following the philosophy of 'adaptive critic' neural networks. The control solution is then mapped back to the spatial domain using the same basis functions. Numerical simulation results are presented for a linear and nonlinear one-dimensional heat equation problem in an infinite time regulator framework.


Arndt's Story: The Life of an Australian Economist. By Peter Coleman, Selwyn Cornish and Peter Drake. Canberra: Asia Pacific Press, Australian National University. 2007. Pp. 338. Professor Heinz Wolfgang Arndt, who passed away on 6 May 2002, was a towering figure in the establishment of the Australian National University's (ANU's) study of Southeast Asian economies. He either directly supervised, or had substantial influence on, a large number of Southeast Asianist academic careers spawned at ANU. He established the Bulletin of Indonesian Economic Studies (BIES), which remains the standard journal in the field on the Indonesian economy. This book concludes that it was ANU's provision for student fieldwork in Indonesia (and other Asian countries) and BIES, under Arndt's leadership, that gave the institution an edge (p. 266). Arndt's contribution to understanding Indonesia's political economy is profound, and lives on with those whom he mentored. He also had some experience of the rest of Asia, including Afghanistan, Hong Kong, Japan, Malaysia, Nepal, Singapore, South Korea, Soviet Central Asia, the Philippines and also Papua New Guinea. Arndt, described in this volume as a German by birth and an "Australian by choice" (p. xiii), went on a difficult journey before finding his place as one of Australia's leading scholars of Asian development. Arndt's Jewish background necessitated the family's flee from Nazi Germany. Arndt himself ended up in the United Kingdom and despite his anti-Nazi credentials he was interned in Canada during World War Ii. Alter the War he moved, first, to Sydney, and then ultimately to Canberra to what was to become ANU. This coincided with an equally colourful intellectual journey. At Oxford University he was, in the words of this book, a "fellow-traveller" of the USSR (p. 21), although he was never a formal member of any communist party. Rejecting the "intellectual flabbiness" of political science and sociology (Arndt commented that "[t]hey seemed to be little more than journalism mixed with pedantry"--p. 43), he transitioned to development economics. His first major publication (with Chatham House), entitled The Economic" Lessons of the Nineteen-Thirties, drew anti-free market lessons from the Great Depression (in contrast to the anti-government intervention lessons derived from the same experience by Hayek and others). By the time Arndt had moved to Australia in the late 1940s he had transitioned to Fabian Socialism (he once advocated the nationalization of Australian banks and attempted to influence Australian politics in the direction of economic planning) and later Keynesianism, and planted himself firmly with the left of the Australian Labour Party (ALP). His view of international relations had shifted to one of suspicion of both superpowers: "[my] own preference is for a critical attitude equally towards the USA and Russia" (p. 85). Years later Arndt would transition to free market economics and split with the ALP over its opposition to the Vietnam War. Arndt believed that the defence of South Vietnam was both a just cause and in the interests of the West. What is not entirely clear from this volume is why and how all these ideological turning points occurred in Arndt's life. What the volume does tell us is that Arndt appeared to solidify his views against Marxism after reading Arthur Koestler's novel Darkness at Noon, and concluded that Marxism-Leninism was "destructive of all intellectual integrity" (p. 43). The volume also notes his trip to India in the 1950s, where he observed a debilitative central planning model that centred on import substitution and paid no regard to comparative advantage. According to the volume: "The hallmarks of Indian economic policy--direct controls, the lack of market incentives and extensive government intervention--were to become anathema to him" (p. 234). Arndt's philosophical transition also seemed to parallel Indonesia's own transition from government intervention (under Soekarno) to free market prescriptions (under Soeharto)--a point not lost on the authors of this book: "This philosophic shift coincided with the Suharto administration's gradual acceptance of comparable advice from American free marketeers" (p. …


The forward (modelled) wavefield for conventional reverse time migration (RTM) is computed by extrapolating the wavefield from an estimated source wavelet. In the typical case of a smooth subsurface velocity, this wavefield lacks the components, including surface reflections, necessary to image multiples in the observed data. We, instead, introduce the concept of forward propagating the recorded data, including direct arrivals, as part of RTM. We analyse the influence of the main components of the data on the imaging process, which include direct arrivals, primaries and surface‐related multiples. In our RTM methodology, this implies correlating the forward extrapolated recorded data wavefield with its reversely extrapolated version prior to applying the zero‐lag cross‐correlation imaging condition. The interaction of the data components with each other in the cross‐correlation process will image primaries and multiples, as well as introduce cross‐talk artefact terms. However, some of these artefacts are present in conventional RTM implementation and they tend to be relatively weak. In fact, for the surface seismic experiment, forward propagating the direct arrivals is almost equivalent to forward propagating a source and it tends to contribute the majority of the data imaging energy. In addition, primaries and multiples recorded in the data become multiples of one higher order. Forward propagating the recorded data to recreate the source will relieve us from the requirement of estimating the source function. It will also include near‐surface information necessary to improve the image in areas with near‐surface complexity. Data from a simple synthetic layered model, as well as the Marmousi model, are used to demonstrate some of these features.


At low grazing angles (LGA), sophisticated electromagnetic scattering of sea surfaces may give rise to complicated surface-current distribution. Therefore, for the multilevel fast multipole algorithm (MLFMA) with the Rao-Wilton-Glisson basis function, the sea scatterer must be meshed fine enough to ensure the precision of the scattering at LGA, which brings huge computational costs. The higher order hierarchical Legendre vector basis functions can bring a great reduction of the unknowns and sparsification of the impedance matrix. The MLFMA with higher order hierarchical Legendre basis functions is applied in the electromagnetic-scattering approach of 3-D breaking water wave crests at LGA for the first time. In addition, an adaptive-order technique is also introduced for the first time in describing the currents which can achieve accurate results and maximally reduce the computational costs from some case analysis. It has been investigated in analyzing the vertically (VV) and horizontally (HH) polarized scattering of profiles of the LONGTANK breaking waves. "Sea-spike" phenomenon has been demonstrated at LGA.


Surface water circulation in the Arctic Ocean is known to vary with time in response to the Arctic Oscillation. Clear recent changes have been documented in the freshwater budget (Rabe et al., 2011) and in the penetration of 129I (Karcher et al., 2012). In the Atlantic Water Layer, the penetration of a warming anomaly, first observed 1990 in Fram Strait (Quadfasel et al., 1991) has been well documented. Much less is known of circulation changes at greater depths.
We compare new 230Th data collected 2007 in the Eurasian and Makarov Basins up to the Alpha Ridge, and 2007-2009 in the southern Canada Basin with previous data from the Arctic Basins. We observe a decreased 230Th content of mid-depth waters (1000-2250m) at the Alpha Ridge compared to data of 1983, and increasing 230Th activities penetrating southward in the Beaufort Sea over the period 2007-2009 in the upper 1500m coincident with the arrival here of the Atlantic temperature anomaly.
We propose that the low-particle flux and high-230Th isolated water mass in the Alpha Ridge region described by Bacon et al. (1989) has been ventilated, resulting in decreased activities in Upper Polar Deep Water here in 2007, and included in an anticyclonic circulation that carried it to the southern regions of the Beaufort Sea.

Bacon, M.P, et al., 1989. Vertical profiles of some natural radionuclides over the Alpha Ridge, Arctic Ocean. Earth Planet. Sci. Lett. 95, 15-22.
Karcher, M.J, et al., 2012. Recent changes of Arctic Ocean circulation revealed by 129 Iodine observations and modelling. Journal of Geophysical Research 117, C08007.
Quadfasel, D., et al., 1991. Warming in the arctic. Nature 350, 385.
Rabe, B., et al., 2011. An assessment of Arctic Ocean freshwater content changes from the 1990s to the 2006-2008 period. Deep Sea Research Part I: Oceanographic Research Papers 58, 173-185.


Processing of YBCO single crystals was carried out by solidification of semi-liquid YBCO composition using a seeding technique. Microstructural characterization of the pinning centers was investigated by transmission electron microscopy. Characterization of single crystals was carried out, relating grain size and shape to the corresponding flux profiles. Current densities were calculated based on measured trapped fields. Once circulating currents were established, flux pumping and quenching experiments were conducted. These large single crystals will be incorporated into electromagnetic forming devices for use in the military and commercial aircraft manufacturing and service industries.<<ETX>>


Purpose: To assess communication skills in children with spastic diplegia. Methods: The study included 20 subjects, 10 preschool children with spastic diplegia and 10 typical matched according to gender, mental age, and socioeconomic status. Assessment procedures were the following: interviews with parents, Stanford – Binet method, Gross Motor Function Classification System, Observing the Communicative Behavior, Vocabulary Test by Peabody Picture, Denver Developmental Screening Test II, MacArthur Development Inventory on Communicative Skills. Statistical analysis was performed using the values of mean, median, minimum and maximum value, and using Student's t-test, Mann-Whitney test, and Paired t-test. Results: Individuals with spastic diplegia, when compared to their peers of the same mental age, presented no significant difference in relation to receptive and expressive vocabulary, fine motor skills, adaptive, personal–social, and language. The most affected area was the gross motor skills in individuals with spastic cerebral palsy. The participation in intervention procedures and the pairing of participants according to mental age may have approximated the performance between groups. Conclusion: There was no statistically significant difference in the comparison between groups, showing appropriate communication skills, although the experimental group has not behaved homogeneously.


. Dogs are the most common companion animals worldwide, motivated by their exceptional social behavior with humans. Unlike many animals, dog learn vocal commands, identify moods, maintain eye contact, and recognize facial expressions. Besides, dogs have great agility and senses of smell and hearing superior to humans, so dogs have been trained for crucial tasks like search, rescue, and assistance. Therefore, it is relevant to do scientific research to understand the fundamentals of behavior and communication that increase the use of its capabilities for the benefit of the human being, guaranteeing the animal's welfare. In this work, a computational method for analyzing dog behavior based on artificial vision techniques was developed. A video database recorded in positive and negative stimuli that induced different emotional states was used. The proposed method determines the dog's emotional state at a given time, which opens a promising field to develop new technologies that trainers and users can take advantage of, to improve the processes of selection, training, and execution of the tasks of working dogs. Using the proposed method, the best test accuracy value we obtained was 0.6917 on the best model trained using transfer learning over the architecture MobileNet, getting good but not perfect results. The training process was carried out using 1067 images distributed among four categories, aggressiveness, anxiety, fear and neutral. The proposed method obtained acceptable results but can still be improved in technical and methodology terms. However, this method can be used as a baseline for exploring and expanding the canine behavior study using computational models.


Adenosine triphosphate (ATP) is an energy compound present in living organisms and is required by living cells for performing operations such as replication, molecules transportation, chemical synthesis, etc. ATP connects with living cells through specialized sites called ATP-sites. ATP-sites are present in various proteins of a living cell. The life span of a cell can be controlled by controlling ATP compounds and without the provision of energy to ATP compounds, cells cannot survive. Countless diseases treatment (such as cancer, diabetes) can be possible once protein active sites are predicted. Considering the need for an algorithm that predicts ATP-sites with higher accuracy and effectiveness, this research work predicts protein ATP sites in a very novel way. Till now Position-specific scoring matrix (PSSM) along with many physicochemical properties have been used as features with deep neural networks in order to create a model that predicts the ATP-sites. To overcome this problem of complex computation, this exertion proposes k-mer feature vectors with simple machine learning (ML) models to attain the same or even better performance with less computation required. Using 2-mer as feature vectors, this research work trained and tested five different models including KNN, Conv1D, XGBoost, SVM and Random Forest. SVM gave the best performance on k-mer features. The accuracy of the created model is 96%, MCC 90% and ROC-AUC is 99%, which are the same or even better in some aspects than the state-of-the-art results. The state-of-the-art results have an accuracy of 97%, MCC 78% and ROC-AUC is 92%. One of the benefits of the created model is that it is much simpler and more accurate.


We address the minimization of the sum of a proper, convex and lower semicontinuous with a (possibly nonconvex) smooth function from the perspective of an implicit dynamical system of forward-backward type. The latter is formulated by means of the gradient of the smooth function and of the proximal point operator of the nonsmooth one. The trajectory generated by the dynamical system is proved to asymptotically converge to a critical point of the objective, provided a regularization of the latter satisfies the Kurdyka-Łojasiewicz property. Convergence rates for the trajectory in terms of the Łojasiewicz exponent of the regularized objective function are also provided.


A common approach to knowledge wh is to try to reduce it to knowledge that, and in particular to answer-knowledge. On this view, the truthconditions of a knowledge wh ascription can be given entirely in terms of which answers to the embedded question the subject knows. Against this background, this paper considers the phenomenon of false-belief sensitivity — a challenge to this common approach to knowledge wh that has recently received a fair amount of attention in the question embedding literature. We present a series of experiments that help to bring the empirical standing of this phenomenon into focus. Across six experiments, our results provide evidence that truth judgments of knowledge wh ascriptions are affected by both the presence of false beliefs and the proportion of the subject's beliefs that are false. Collectively, these results demonstrate a pattern of judgments that is incompatible with standard accounts of the relationship between knowledge that and knowledge wh, and with reducibility more generally. After presenting these new data, we end by considering the theoretical implications of this richer descriptive picture and outline a number of remaining open questions that should be pursued


In this publication a new enhanced V-Model for interdisciplinary product engineering is presented. The new approach comprises continuous requirements elicitation and management, comprehensive modeling and analysis and emphasis on the entire product life cycle. The proposed V-Model unites the models of different development methodologies, e.g. VDI 2221 [3], Systems Engineering [4] and elements of the contemporary VDI 2206 [2]. This new approach is inspired by discussions led within the Technical Committee VDI GMA 4.10 "Interdisciplinary Product Creation" of the Association of German Engineers (VDI).


In the mid 1970's, 19 controlled experiments in the marketplace were conducted by the Campbell Soup Company to evaluate the sales impact of advertising changes for various well established packaged food brands. Changes evaluated included: budget levels, seasonality, media type and mix, creative strategy and audience targeted. Markets defined by Selling Areas Marketing Inc. SAMI were used as the experimental units.

One of the main findings that emerged when the experiments were viewed as a whole was that budget levels, given existing creative executions, generally had little or no impact on the sales of these well established brands. However, changes in copy strategy, media selection, media mix and targeting often produced a substantial payout. These findings had a significant influence on advertising strategy at Campbell Soup Company and led to:

a Greater emphasis on strategic development and evaluation of copy.

b Evaluation of a larger number of sometimes unconventional media.

c Implementation of much greater differences in advertising weight in budget level tests.


For the thermal design of combustion chambers and turbine blades in jet engines, a detailed knowledge of the combustion and of the heat loads to the walls is necessary. In general, high operating temperatures and reduced combustor size are striven for in order to increase engine efficiency and reduce weight. Consequently, the components are exposed to temperatures above the melting point of the materials and there is a growing risk of incomplete combustion within the combustion chambers. To study these effects, we set up a new test bench for fundamental investigation of chemical near-wall reactions at atmospheric pressure. First results of gaseous, non-premixed near-wall CH4/air and H2/air flames are presented. Optical methods such as two-line laser-induced fluorescence thermometry and OH* chemiluminescence were applied. Further, the heat release to the wall was determined by means of inverse heat conduction calculation using the data of implemented thermocouples.


Nanostructures, created by confinement of the motion of an electron from all three dimensions and known as quantum dots (QDs), provide materials scientists with a wide range of potential applications. These structures are produced today with advances of QD growth technology, and computational tools are fundamental in providing a better understanding of such structures. In this paper QD nanostructures are analysed with due account for coupling effects between electronic states in the dot and the wetting layer regions. The analysis, performed on the basis of the finite element methodology and Arnoldi iterations, demonstrates that the effect of coupling may be essential. The numerical procedure applied here is more efficient compared to the QR algorithm typically used in the context of modelling low-dimensional nanostructures. We report results of computational experiments for cylindrical and truncated conical QDs and compare them with the earlier results obtained for fully conical QD nanostructures.


Physician implicit racial bias has been found to predict racial minority patients' reports of satisfaction and trust immediately after engaging in racially discordant medical interactions. This suggests physician implicit racial bias is somehow manifested in physician communication behaviors and noticed by patients during the medical interactions. However, it is unclear exactly how physician implicit racial bias manifests behaviorally during racially discordant medical interactions. The authors argue that such lack of understanding might be due to several limitations with the existing patient-physician coding systems. In order to further advance research on patient-physician communication during racially discordant medical interactions, new coding systems tailored for racially discordant medical interactions are required. Specifically, it is suggested that these coding systems need to be capable of assessing physician nonverbal/paraverbal communication behaviors that were found to be positive or negative by racial minority patients themselves. This likely requires innovative research approaches, such as a mixed-methods approach.


Abstract Objectives To analyse the nature and content of advertising during children's popular television viewing times with the specific aims of (i) identifying the proportion of advertising time devoted to confectionery and potentially cariogenic products (those which readily give rise to dental caries, more commonly known as tooth decay); and (ii) determining whether there is a variation in the advertisement of confectionery and other high-sugar products within children's school holiday time v. outside holiday time. Method In five separate one-week periods, the output of the four most popular British children's commercial television channels was video-recorded during the most popular viewing times for children. In total, 503 h of television were recorded and analysed. Results Analysis of the recordings revealed that 16·4 % of advertising time was devoted to food products; 6·3 % of all advertising time was devoted to potentially cariogenic products. Sugared cereals were the most commonly advertised high-sugar product, followed by sweetened dairy products and confectionery (χ2 = 6524·8, df = 4, P < 0·001). The advertisement of confectionery and high-sugar foods appeared to be influenced by school holidays. Conclusions Health-care professionals should be aware of the shift away from the advertisement of confectionery towards the promotion of foods that might be considered healthier but contain large amounts of hidden sugar.


Goals To determine the prevalence of irritable bowel syndrome (IBS) in subjects with gastroesophageal reflux disease (GERD) compared with non-GERD controls. Study Two hundred subjects were identified from a list of Cedars-Sinai Medical Foundation patients and gastroenterology motility practice subjects with and without a potential diagnosis of GERD. All subjects were then evaluated independently by two blinded physicians who were asked to identify subjects with GERD based on taking a history (gold standard). A follow-up questionnaire was later mailed to patients. This questionnaire included Rome I criteria for IBS. The prevalence of IBS was compared between GERD and non-GERD subjects. Finally, to further strengthen the method, a retrospective review of all subjects' charts was conducted to identify patients who had had 24-hour pH tests, and the prevalence of IBS was determined in this subgroup. Results Of the 200 subjects, 90 (45%) patients returned the questionnaire. After excluding subjects with IBD and incomplete questionnaires, there were 84 subjects (35 with GERD) included in the analysis. Of the 35 GERD subjects, 25 (71%) were Rome I criteria positive for IBS, whereas only 17 of the 49 (35%) non-GERD subjects had IBS (odds ratio = 54.7, CI = 1.7–13.5, p < 0.01). In 11 of the GERD subjects a 24-hour pH study was available and confirmed GERD. Of these 11 subjects, 7 (64%) met Rome I criteria for IBS. Conclusion There is a higher prevalence of IBS in subjects with GERD compared with subjects without GERD.


Background: The question of whether or not abdominoplasty is associated with permanent weight reduction remains controversial. In coalition, should abdominoplasty be used as an adjunct for weight reduction in the overweight/obese patient? Methods: This retrospective patient case series attempts to determine the most important factors associated with weight reduction. Results: All patients undergoing abdominoplasty had weight loss beyond that of their resected pannus, with a minimum body mass index reached 11.6 ± 1.7 weeks after surgery. Weight loss is attributed to an increase in satiety by 75 percent (n = 15) of patients. Preoperative body mass index greater than or equal to 24.5 kg/m2 can be used to predict long-term weight loss with a sensitivity and specificity of 92.9 percent and 83.3 percent, respectively. Patients above this threshold achieved significantly more weight loss (−4.5 ± 1.4 percent body mass index) at 1 year compared with their lower body mass index counterparts (p = 0.014), as did those with pannus resections weighing greater than 4.5 lb (p = 0.01). Conclusions: Abdominoplasty performed on patients with a body mass index greater than 24.5 kg/m2 appears to be linked to sustained weight loss at 1 year. Satiety appears to be a prominent contributing factor, as does the amount of fat resected. Possible neurocrine mechanisms are discussed. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


ABSTRACT
 "Mal de Río Cuarto," is the most important virus disease of corn, Zea mays L., in Argentina. It is caused by the Mal de Río Cuarto virus (family Reoviridae, genus Fijivirus. MRCV), which is a persistent virus transmitted by Delphacodes kuscheli (Fennah 1955) (Hemiptera: Delphacidae). Because corn is not a natural host of D. kuscheli, it has little protection from this pest. In contrast, wheat, Triticum aestivum L., is one of the main hosts of this vector and a reservoir of MRCV. The aim of this work was to identify genes involved in antixenosis, antibiosis, and tolerance of infestation by D. kuscheli in wheat, which might be used to reduce the population level of this vector on corn. A set of recombinant dihaploid (RDH) lines for chromosome 6A derived from the F1 cross between 'Chinese Spring' (CS) × 'Chinese Spring (Synthetic 6A)' (S6A) substitution line, was used for mapping. The S6A parental line is resistant to the MRCV vector. Antixenosis, antibiosis, and tolerance were evaluated using conventional tests in controlled environmental conditions. Most of the RDH and S6A showed higher levels of antixenosis against D. kuscheli than the parental line CS. The RDH lines showed highly significant antibiosis in terms of the duration of first, third, and fifth nymphal instars, developmental time (days), survival and fecundity. There were highly significant differences in the tolerance to D. kuscheli based on the chlorophyll content of the first and second leaves, foliar area, and aboveground fresh and dry weights. The duration of the fifth nymphal instar and the developmental period were significantly associated with Xgwm1017 marker loci, located at 48 cM on 6AL. Another quantitative trait locus accounting for the variation in chlorophyll content of the first leaf was associated with the interval between loci Xgwm459 and Xgwm334a, located in the telomeric region of the 6AS chromosome arm. The alleles with positive effects came from S6A. Antibiotic resistance of RDH could be useful for controlling the population increase of the MRCV vector on wheat, because prolonging the duration of development increases the period between two subsequent generations, so reducing the abundance of infective populations colonizing corn.


This paper explores the financial sustainability of a typical U.S. state defined-benefit pension fund under the continuation of current policies and under alternative policies, such as alternative contribution, indexation and investment allocation policies. We explore the "classic" asset-liability management (ALM) results, which indicate that a policy of conditional indexation may substantially improve the financial position of the fund. We also investigate the value-based ALM results, which provide a market-based evaluation of the net benefits of the contract to the various stakeholders. All participant cohorts under our simulation horizon derive a substantial net benefit from the pension contract, implying that tax payers make substantial contributions to this pension arrangement. The aforementioned measures can be instrumental in alleviating the burden on the tax payer, though this will happen at the cost of a reduction in the value of the contract to the participants.


Mexico is still a "young" country with pressing burdens on education, especially at
secondary and high school levels, and high percentages of the population entering
the work force each year. Yet, it will complete its "demographic transition" in the
next 20-25 years with a rapid increase in the percentage of population 65 years
and older.
As with most Latin American countries, Mexico is experiencing what experts call a
"mixed" epidemiological transition with increasing trends in prevalence of chronic
diseases and a marked decrease in communicable diseases in some areas, but with
a continuing moderate or high incidence of the latter in some regions of the
country. In addition, there are no long-term care programmes that cater to the
specific health and social care needs of the older population. Services for the elderly
are comprised of isolated strategies mainly recreational and information
programmes, and health services similar to those provided to all other
age/condition groups in the country. At the moment, social development and health
sectors are unprepared to cater for the needs of the increasing elderly population.
Currently, the majority of the older population live with their children, or other
close relatives, and most of the care provided to them is done at home by their
family members. Nevertheless, changes in fertility rates, constant rural-urban
migration within Mexico and international migration, women's increasing
participation in the labour force, among other factors have changed family size and
composition and may pose future challenges to the availability of household care
and support.
Given the rapid ageing process Mexico is going through, the absence of dedicated
strategies for the older population and the possible decrease in availability of
informal care, there is a pressing need to have detailed information on the
conditions of the older population and how they are experiencing the ageing
process. Mainly, on their health and disability status, on their use of services by the
elderly, and on the characteristics of the informal care that is provided to them.
The main objective of this research is to generate significant information in order to
provide health system institutions with information on specific needs and on the
provision of social and health care services for the elderly in Mexico in the next
decades.
The aim of the thesis was to generate information on the dynamics of the ageing
process in Mexico and how the Mexican population is facing old age. This was done
by exploring four main topics.
First, a comprehensive study of their health and disability status was done,
including the generation of a Frailty Index in order to have an additional indicator of
their overall health and frailty status at individual and population level.
Secondly, overall survival in the Mexican ageing population was investigated.
Through the analysis, possible differences between sub-samples of the population
were explored.
Given that there are no formal long-term care services for the older population in
Mexico, the remaining topics are related to the care for this population group. On
one hand, the thesis explores the use of health services by the ageing population in
Mexico. This includes the use of different types of care such as general practitioner,
specialist doctors, as well as inpatient and outpatient hospital visits. On the other
hand, it explores the supply of informal care for the older population by their (co-
resident and non-resident) children.
The thesis then addresses future challenges regarding the ageing process and
formal and informal care-giving. Finally, following the identified challenges, the
thesis includes recommendations for future research and inputs for future
-
health
and social-ageing policies and strategies in Mexico.
Data for the research come from the two existing waves of the Mexican Health and
Ageing Study, MHAS (2001 and 2003). This is a prospective panel study of health
and aging in Mexico which includes a nationally representative sample of population
50 years and older.


The process of implementing new laws in an environment of social change shares many characteristics with the process of making investment decisions under uncertainty. In any society that is not totally static, the law maker faces uncertainty about its evolution. Thus, the lawmaker cannot know with certainty what the appropriate law will be in the future, and therefore cannot know with certainty what the future stream of benefits from the law will be. In addition, implementing a new law necessitates the outlay of resources in formulating and enforcing the law, just as investment in a new project does. The costs of implementing a new law are largely sunk, and irreversible. That is, the costs of implementing the law cannot be recovered if the law turns out to be inappropriate in any way. Thus, the lawmaker faces a decision akin to an irreversible investment under uncertainty. Timing of the investment is therefore a critical issue for irreversible investments. When the lawmaker chooses to invest in the new law, he gives up the option to wait to implement the law at some future time. This option is the opportunity cost of investing today. At the same time, there is a cost in delaying the implementation of new laws, due to the decreasing effectiveness of the old laws in the changing social environment. That is, there is an "opportunity benefit" in investing today. In determining the optimal timing of adoption of new laws, the value of the option of waiting must be taken into account. We present a formal model drawn from the investment literature to demonstrate the value of waiting, and discuss its implications in the context of two real world legislative problems, environmental laws and privacy regulation. In both cases, there might be a cost in delaying investment in new laws, in that the damage to the environment or privacy could be irreversible. On the other hand, the benefits of the laws are hard to estimate. In addition, compliance costs might be very large, and the value of waiting correspondingly important in the decision to invest in lawmaking.


Vertebrate genomes are comprised of isochores that are relatively long (>100 kb) regions with a relatively homogenous (either GC-rich or AT-rich) base composition and with rather sharp boundaries with neighboring isochores. Mammals and living archosaurs (birds and crocodilians) have heterogeneous genomes that include very GC-rich isochores. In sharp contrast, the genomes of amphibians and fishes are more homogeneous and they have a lower overall GC content. Because DNA with higher GC content is more thermostable, the elevated GC content of mammalian and archosaurian DNA has been hypothesized to be an adaptation to higher body temperatures. This hypothesis can be tested by examining structure of isochores across the reptilian clade, which includes the archosaurs, testudines (turtles), and lepidosaurs (lizards and snakes), because reptiles exhibit diverse body sizes, metabolic rates, and patterns of thermoregulation. This study focuses on a comparative analysis of a new set of expressed genes of the red-eared slider turtle and orthologs of the turtle genes in mammalian (human, mouse, dog, and opossum), archosaurian (chicken and alligator), and amphibian (western clawed frog) genomes. EST (expressed sequence tag) data from a turtle cDNA library enriched for genes that have specialized functions (developmental genes) revealed using the GC content of the third-codon-position to examine isochore structure requires careful consideration of the types of genes examined. The more highly expressed genes (e.g., housekeeping genes) are more likely to be GC-rich than are genes with specialized functions. However, the set of highly expressed turtle genes demonstrated that the turtle genome has a GC content that is intermediate between the GC-poor amphibians and the GC-rich mammals and archosaurs. There was a strong correlation between the GC content of all turtle genes and the GC content of other vertebrate genes, with the slope of the line describing this relationship also indicating that the isochore structure of turtles is intermediate between that of amphibians and other amniotes. These data are consistent with some thermal hypotheses of isochore evolution, but we believe that the credible set of models for isochore evolution still includes a variety of models. These data expand the amount of genomic data available from reptiles upon which future studies of reptilian genomics can build.


Rain, wind, hail, and unavoidable harvest delays have led to lodged and flat hayfields across the state. This is not usually a concern in more normal seasons, but if it occurs, producers have to manage for and around it. A 'bright side' of delayed harvest is that the forage plants have longer to accumulate carbohydrate 'stores' and maintain plant vigor. Just because hay lodges, does not mean that it will 'smother itself.' New alfalfa and grass shoots that will become the second growth will emerge through the older, lodged first growth. However, harvesting this combined first and partial second growth will interrupt the development of the second growth and likely slow its eventual regrowth. So, there may be a slightly longer interval between your first and second cuts this year.


We have illustrated methods to address three types of problems in static analysis for Ada tasking: quantitative questions, safety problems and MAY-happen event problems. We have applied a two-phase methodology to automate analysis: first deriving a semantically rich model independent of any specific analysis issue, that is the original Ada nets, and then manipulating this model with algorithms that are designed for the specific analysis issue of concern. We call such a methodology the query-driven net reduction. The philosophy behind this methodology is that different analyses demand different aspects of information from the system. An optimized analysis model should only contain the necessary information. In addition to reachability graph generation, the linear algebraic method is also investigated as a follow-up analysis technique. Experiments show that the net reduction technique substantially enhances the analysis ability of both state space generation approaches and linear algebraic methods.<<ETX>>


Developing thermoelectric materials with high ZT revolves around various processing techniques, such as doping, substitution chemistry, and band structure engineering near the Fermi level due to embedded nanoscale precipitates and/or quantum dots, and more recently introduced compositionally alloyed hierarchically organized microstructures. In this work, we have extended atomic scale structural engineering combined with an overarching panoscopic approach enabling the development of hierarchically organized microstructures at multiple length scales to Hf-free p-type half-Heusler thermoelectric materials for the first time. A series of compositions ZrCo1+xSb0.9Sn0.1 have been synthesized employing a fast processing technique of arc melting followed by conventional hot pressing revealing composites of half-Heusler (HH) and full-Heusler (FH) at multiple length scales. Such microstructural modifications at various length scales lead to controlled tuning of the hole density, effective mass and band engineering. Interestingly, a simultaneous large enhancement of the power factor (72% >) and a reduction in thermal conductivity (30% >) of the resulting ZrCo1+xSb0.9Sn0.1 composites were observed. The enhancement in the power factor was primarily due to the increased Seebeck coefficient which resulted from a reduction in the effective hole carrier density via low energy electron filtering coupled with an increase in the hole carrier's effective mass (m*) due to band off-set minimization. The reduction in thermal conductivity can be ascribed to the enhanced phonon scattering by different frequency heat-carrying phonons due to various grain sizes at multiple length scales, such unique specific design strategies of materials described here result in superior thermoelectric properties which have been compared with several state-of-the-art p-type half Heusler materials. The Bergman-Fel model is used to calculate the effective thermoelectric parameters of these composites for comparing the experimental results.


From Hanoi to Hollywood: The Vietnam War in American Film Edited by Linda Dittmar and Gene Michaud. New Brunswick: Rutgers University Press, 1991. 387 pp. Illustrated. $45.00 (cloth), $14.95 (paper). I received this book on the day that the Persian Gulf War began, Operation Desert Storm, the war, according to President Bush, that will create a "new world order." Dittmar and Michaud begin their introductory essay to this collection of essays about Vietnam War films, "This book is about power. Implicitly, it is about the power to make war and to destroy lives. Explicitly, it is about the power to make images that may displace, distort, and destroy knowledge of the history in which those lives participated." It was both instructive and unnerving to read the twenty essays in this book while listening to American "officials" censoring and manipulating the words and images associated with the present war. Dittmar and Michaud also remind us that the title of their book "is meant to draw attention to the process whereby aspects of that war [Vietnam] have been appropriated into particular modes of representation by sectors of the American cultural industry." The essays are arranged into four thematic categories: "Wide Angles: History in the Remaking," "Close-ups: Representation in Detail," "Other Frames: Subtext and Difference," and "Other Forms: Documenting the Vietnam War." The book includes two appendices, "Chronology: The United States, Vietnam and American Film," and "Selected Filmography: The Vietnam War on Film." While the essays vary in style and approach, they share a concern for the relationship between history and its representation in film. This collection of essays focuses on how films are, the editors state, "bound by the commodity status of films produced under the conditions of capitalism." The Vietnam War and historical specificity have been influenced by American culture, ideology, world historical events, and the techniques of film production itself. These and other factors helped to shape every film about the Vietnam War from Green Berets (1968) to Full Metal Jacket (1987). The first essay, "Historical Memory, Film and the Vietnam Era" by Michael Klein points to how revisionism and reinterpretation take place in a historical era. He reminds the reader of how historical myths about the Civil War era were represented in D.W. Griffith's The Birth of a Nation (1915) and Gone With the Wind (1939). Keeping in mind that Hollywood did not produce many Vietnam movies until nearly a decade after America's involvement in the war, Klein and other authors explore how the nation's political and public atmospheres play a deciding role in the content and images included in Vietnam War films. Klein discusses how Hollywood encodes the generic melodramas with an "eye to ideology." The Deer Hunter ( 1978) is "pervaded by racist and Cold War stereotypes." Hollywood's demonological approach to Asians in general, and Vietnamese "Communists" in particular has generated countless "vigilante" style characters who simply must fight the "yellow peril" with means other than conventional warfare. Klein uses Platoon as an example of a film that "substitutes a psychological and metaphysical interpretation for a historical understanding of the genocidal aspects of the war." Leo Cawley's essay, "The War About the War: Vietnam Films and the American Myth," discusses the "mindless military rambunctiousness" of Americans and their love of John Wayne super-troopers and military technology as depicted in Hollywood war films. Cawley, a combat veteran in Vietnam, reminds us that most soldiers do not like super-troopers and that technology was not all that relevant in the Vietnam War. "In Vietnam films, experience is masticated into the form most easily incorporated into American mythology," Cawley asserts. Part of this mythology is also discussed by Harry W. Heines in "They Were Called and They Went: The Political Rehabilitation of the Vietnam Veteran. …


Effect of esculentoside H (EH) on release of tumor necrosis factor (TNF) from murine peritoneal macrophage (Mphi) in vitro was studied. The results showed that EH (12.5-200 micrograms.ml-1) induced the thioglycolate-broth elicited peritoneal Mphi to release TNF into supernatants in a dose-dependent manner, and higher levels of TNF activity were detected in the supernatants from EH-stimulated calcimycin-primed Mø culture. EH-induced TNF release had a different type of kinetics compared with that of lipopolysaccharides (LPS). LPS-induced release of TNF increased rapidly until 6 h after LPS stimulation, then declined gradually, while EH-induced TNF release increased gradually after EH stimulation and reached its peak at approximately 24 h later. These results suggested that the anti-tumor mechanisms of Phytolaccaceae may be related to the capacity of EH for TNF release.


"Gion Caminada has left tangible traces of the dialogue with the building tradition of his region, the Grisons. On closer inspection, however, he does not design by following history: he does not take up or add, but reconceptualizes knowledge in new spatial experiences, interpreting what already exists and sometimes combining it with "finds" from other historical sources.
The awareness that nothing interesting can arise from copies faithful to the original leads to the belief that designing "with history" implies a transformation.
Gion Caminada is an architect who interprets the construction traditions of his place very serenely, designing on them and at the same time updating their meanings. Think of the revival of the Strickbau, one of the oldest methods of building with timber in Grisons, which has been reinterpreted in a freer way to create smoother transitions between rooms inside the buildings and generate a refined interaction between open and closed spaces or even create unprecedented relationships between the inside and the outside.
At the same time, the study of his projects reveals other historical references in the field of international art and architecture of the past, an aspect that is clear for example in its similarity to concrete art, neoplasticism, and constructivism, through a strong interest in the creation of plastic and sculptural spaces.
Therefore, designing "with history" does not imply a repetition of what history itself, a place, a memory, or an image "present" to the architect, but a comparison and a further thought."


The article deals with the evaluation of sugar beet based on crystallization tests of thick juice. A standard methodology was developed of measuring the yield of sugar based on crystallization tests with thick juice, including programs for preparation, control and evaluation of tests and the relations between the composition of nonsugars in sugar beet and the sugar residue in molasses or the yield of sugar. The methodology can be utilized by cultivators and processors of sugar beet for evaluation of technological quality of sugar beet. A valuable result of the project is the extensive data bank of properties of sugar beet pertinent to current conditions of its cultivation in the Czech Republic. The data bank can be used by sugar beet cultivators, the sugar manufacture community and in projects dealing with new perspectives and potentials of sugar beet utilization.


Tuning codes for GPGPU architectures is challenging because few performance tools can pinpoint the exact causes of execution bottlenecks. While profiling applications can reveal execution behavior with a particular architecture, the abundance of collected information can also overwhelm the user. Moreover, performance counters provide cumulative values but does not attribute events to code regions, which makes identifying performance hot spots difficult. This research focuses on characterizing the behavior of GPU application kernels and its performance at the node level by providing a visualization and metrics display that indicates the behavior of the application with respect to the underlying architecture. We demonstrate the effectiveness of our techniques with LAMMPS and LULESH application case studies on a variety of GPU architectures. By sampling instruction mixes for kernel execution runs, we reveal a variety of intrinsic program characteristics relating to computation, memory and control flow.


Despite introduction of Information Communication Technology in schools by Government of Kenya, minimal research has been done on influence of learning strategies in information communication technology use on academic self-concept of pupils. Academic self-concept has a reciprocal relationship with academic achievement. Poor trends in academic achievement are associated with pupils' low academic self-concept as an outcome of continued use of traditional learning strategies. This may be alleviated by use of information communication technology in the learning process. The purpose of the present study was therefore to investigate gender differences in academic self-concept among pupils using learning strategies in the use of information communication technology. Multimedia Learning Theory, Collaborative Learning Theory and the Self Theory of Personality Development formed the theoretical framework of the study. A causal comparative ex post facto research design was used. The study employed mixed methods research by integrating qualitative and quantitative research. The study was done in Bungoma County. The target population was Standard Seven pupils in public primary schools in Bungoma County. A sample of 375 pupils was involved. Purposive sampling was used to select schools with computer program as treatment group and simple random sampling for schools using traditional learning strategies as comparison group. Independent and dependent variables were learning strategies and academic self-concept (measured in 3 dimensions) respectively. Data was collected through an adapted questionnaire with Academic Self-concept Scale and Learning Strategy Rating Scale for learning strategies. Oral interviews and non-participant overt observations were used to collect qualitative data from pupils and teachers who handled learners in the laptop computer programs. The reliability and validity of the instruments was established through a pilot study in 2 sampled schools which were not included in the main study. Data management and analysis was done using both inferential and descriptive statistics using Statistical Package for Social Sciences program. Pearson product moment correlation and t-test were used for inferential statistics. Results showed that there were no significant gender differences in academic self-concept among pupils using traditional learning strategies and those using learning strategies in the use of ICT (t=1.151, t=1.03,-1.494 df=168.191, 182.979 and 165.341, p> 0.05 and (t= 1.422, -0.178 and 0.386, df=178.3 94,180.903 and 175.616, p> 0.05) for treatment and comparison groups respectively. Recommendations for adoption of learning strategies in information communication technology use in classroom teaching and learning, policy development in education and curriculum development were made. Further research using pre-test and post-test experimental design with control group using samples at other levels of education and on individual subject academic self-concept was recommended.


Flexible dye-sensitized solar cells (DSCs) were prepared by using carbon nanotube transparent conductive films (CNT-TCFs) as flexible substrates, and their photovoltaic properties were investigated as well. The flexible DSCs show typical photovoltaic characteristics with short-circuit current of 0.78 μA and open-circuit voltage of 1.48 mV, which was strongly influenced by heat-treatment temperature, type of dyes, and electrical resistivity. In light of their lighter weight and higher flexibility than conventional DSCs based on conductive glass substrates, the flexible DSCs have great potential as functional photoelectric components in many fields.


The study of minimal residual disease is an attempt to redefine the concept of remission. Opinion as to the clinical utility of minimal residual disease is still in evolution. It has become clear that the ability to merely detect minimal residual disease by the polymerase chain reaction amplification of the molecular "fingerprint" of a leukemia does not always foretell relapse. Rather, careful consideration must be taken of the context of the type of disease, the molecular lesion itself, and the type of therapy employed. Thus although the detection of minimal residual disease in acute lymphoblastic leukemia or acute promyelocytic leukemia has a high correlation with relapse, detection of minimal residual disease in t(8;21) acute myelogenous leukemia has little correlation with relapse. In some diseases (eg, chronic myeloid leukemia) the clinical relevance of minimal residual disease detection may be strengthened by quantification, although this in itself introduces another level of complexity and potential pitfalls. Nevertheless, we are moving toward the day when the molecular definition of disease status will guide therapy.


Both climate and cultivated land area of Puan County, Guizhou Province, China are briefly described. The six steps of Gray Series Forecasting Model are introduced, including generation of series, generation of mean value, establishment of GM (1,1) model, reducing reaction, reliability test, and extrapolation forecast. According to the data of cultivated land area in Puan County from the year 1998 to 2007, Gray System Theory is used to establish the Gray Series Forecasting Model of cultivated land area in Puan City. Since it has passed the reliability test, this model has relatively high fitting accuracy and can be used for extrapolation forecast. Based on this Gray Series Forecasting Model, extrapolation forecast of cultivated land change is conducted in Puan County from 2009 to 2012. Result shows that the expected area of cultivated land will be reduced by 1050 hectares in the years 2009-2012, an annual decrease of 270 hectares. Cultivated land area shows a declining trend year by year. Result of the forecasting model is close to actual value with small prediction error. Thus, it can be concluded that the result is basically credible.


Information on past dryland environments is commonly derived from geomorphological landforms and sediments ('geoproxies'). The Okavango Delta in the middle Kalahari, Botswana, has been subject to a long history of arid–humid transitions but its potentially rich archive of fluvial geoproxies is largely untapped. Previous palaeoenvironmental studies in the Delta region have focused mainly on aeolian dunes, lacustrine beach ridges, and rare pollen sequences in surrounding locations, and the Delta's channel dynamics have remained poorly constrained, both chronologically and in quantitative palaeohydrological terms. Focusing on the Delta's Xugana region, we present the first optically stimulated luminescence ages for palaeochannel fills and scroll bars, revealing significantly enhanced fluvial activity in the ~7–4 ka interval. Along 120–150 m‐wide, sand‐bed, sinuous palaeochannels, lateral migration and bend cutoffs were driven by palaeodischarges up to ~350–450 m3 s−1, at least nine times those of the present‐day channels. These palaeochannels represent the last major phase of meander activity in the middle and lower Delta. The palaeodischarges imply significantly higher rainfall over the catchment in the mid Holocene, possibly resulting from a southwards shift of the African tropical rainbelt. Over the last few thousand years, diminished fluvial activity in the Xugana region has continued; <20 m‐wide channels with discharges typically <40 m3 s−1 have been more laterally stable, albeit subject to local avulsions. These findings provide the 'missing link' between evidence for past intervals of enhanced rainfall in the Delta's tributary catchments in the northwest and west and the filling of large lacustrine basins to the southeast and east. The findings contribute to improved understanding of changing Kalahari hydroclimates and support growing evidence indicating that the mid to late Holocene was a time of significant fluvial transformation across many of the world's drylands.


Human Tracking in Computer Vision is a very active up-going research area. Previous works analyze this topic by applying algorithms and features extraction in 2D, while 3D tracking is quite an unexplored filed, especially concerning multi–camera systems. Our approach discussed in this paper is focused on the detection and tracking of human postures using multiple RGB–D data together with stereo cameras. We use low–cost devices, such as Microsoft Kinect and a people counter, based on a stereo system. The novelty of our technique concerns the synchronization of multiple devices and the determination of their exterior and relative orientation in space, based on a common world coordinate system. Furthermore, this is used for applying Bundle Adjustment to obtain a unique 3D scene, which is then used as a starting point for the detection and tracking of humans and extract significant metrics from the datasets acquired. In this article, the approaches are described for the determination of the exterior and absolute orientation. Subsequently, it is shown how a common point cloud is formed. Finally, some results for object detection and tracking, based on 3D point clouds, are presented.


Sub-Sahara African (SSA) countries have become more integrated with the world economy since the early 1990s leading to a surge in international capital inflows, but have also experienced sporadic downfalls in their growth rates leading to instabilities in some macroeconomic variables. This paper examined the dynamic and causal relationship between economic growth and international capital inflow in SSA using data covering the period of 1990 to 2018. Through Structural Vector Autoregression (SVAR) impulse response and variance decomposition, the study found a positive relationship between growth and international capital inflow in SSA. It also found negative relationships between macroeconomic instability and economic growth; and macroeconomic instability and international capital inflow in SSA. In addition, through VAR Granger Causality or Block Exogeneity Wald Tests, the study found a unidirectional causal relationship running from growth to international capital inflow in SSA. The study also found that international capital inflow did not cause economic growth but economic growth attracts international capital inflows. Therefore, the study concluded that a buoyant and viable economy provides conducive business environment for international investors better than less viable economy. Thus, the study recommended that governments and policy makers in SSA should put in place policies that will promote economic growth to attract more international capital inflows which would augment the scarcely available domestic capital resources most especially in terms of knowledge, skills and other technological advancement, that would later translate into further economic growth in SSA region.


The proper fabrication of provisional restorations is integral to the overall success of restorative dentistry, as these templates are the initial architecture for the completed case. In a clinical setting, restorations may be utilized for an extended period, during which time the clinician and patient must feel confident. Due partially to a new generation of dental materials with unique properties, provisionalization can be predictably achieved. This article reviews the clinical criteria for the fabrication of interim restorations using a light cure/dual phase temporary crown and bridge material (Provipont DC, Ivoclar Vivadent, Amherst, NY) and its effect on the overall success of restorative procedures, including anterior and posterior restorations.


In the last few decades stochastic dynamic modeling (SDM) has been used to explore adaptive state-dependent strategies in a whole host of different theoretical problems in behavioural ecology, with considerable success. It has allowed us to better understand cooperative behaviours such as sentinel behaviour, and it might allow us to more fully understand other cooperative behaviours with alternative dynamics. In a recently developed SDM, anti-predator behaviour was examined and a counter-intuitive prediction has emerged: that mobbing effort should be completely independent of state. In this study we test this interesting prediction, using the cooperatively breeding Apostlebird (Struthidea cinerea) as our study species. From October 15th to November 21st in 2009, 6 groups of varying sizes were put through a set of trials, where we used a rubber snake model to elicit mobbing behaviour in experimental trials. A similarly sized stick was used during control trials, wherein birds tended to forage. Behaviour, placement and vocalisation data on an individual basis were gathered in multiple scan samplings per trial in both kinds of treatment. This highly accurate data was then compared with within-individual differences in body mass (state). Several other variables were also considered: sex, age, breeding status, relatedness and mean body mass. Results show that while foraging behaviour was highly state-dependent during controls, no such effect was found in the mobbing effort of the same individuals during experiments. Mobbing effort also did not vary with any of the mentioned phenotypically fixed variables. Our study therefore offers the first empirical evidence of state-independent mobbing.


Performance improvements in graphics hardware and the diffusion of the low cost haptic interfaces have made it possible to visualize complex virtual environments and provided opportunities to interact with these in a more realistic way. In this paper a Virtual Reality application of a game of billiards is presented. By means of a commercial haptic interface a force feedback is provided, thus rendering the interaction realistic and exciting to the user. The introduction of the force feedback makes it possible to obtain a realistic simulation as it is possible to strike the billiard ball and to feel the contact between cue and ball. The virtual environment has been built using the development environment XVR and rigid body dynamics have been simulated utilizing the ODE library. Since in the real game it is possible to use the left hand when aiming and striking the ball, in the play modality it is possible to fix the cue movement in the desired direction in order to allow a more careful aim and a more stable interaction in the virtual environment. In addition it is possible to choose the force with which the ball is hit.


Head and neck squamous cell carcinoma (HNSCC) is a commonly occurring malignancy associated with severe morbidity, persistently high mortality rates, frequent recurrence, and the appearance of second primary tumors (SPTs). A great need exists, therefore, for new therapies, including complementary and preventive approaches to treating HNSCC. Signal transducer and activator of transcription (STAT)-3, an oncogenic transcription factor, shows promise as an important therapeutic target in the treatment of HNSCC. The current study focuses on the STAT3-targeting activities of two natural compounds, guggulsterone and honokiol, and investigation of their antitumor activity in HNSCC. Guggulsterone, a compound contained in the resin of the Commiphora mukul plant, used in Indian Ayurvedic medicine, is widely available as a dietary supplement and associated with few side effects. Honokiol is a naturally-occurring compound that has been used in traditional Chinese medicine and is derived from the plant, Magnolia officinalis. Both compounds have been shown to have anticancer activity in various models and to inhibit nuclear factor kappa B (NF kappa B), an oncogenic transcription factor. NF kappa B and STAT3 interact with one another in various ways. Therefore, we hypothesized that guggulsterone and/or honokiol might be useful in targeting STAT3. Both compounds inhibited growth and invasiveness and induced apoptosis in HNSCC cell lines, in addition to decreasing levels of phosphotyrosine STAT3, and, for guggulsterone, total STAT3. Guggulsterone was also found to cause cell cycle arrest and to target hypoxia-inducible factor (HIF)-1 alpha, a potential therapeutic target whose expression is correlated with poor clinical outcome in HNSCC. Guggulsterone-induced growth inhibition relied partly on its ability to inhibit STAT3. Both compounds enhanced the activities of current HNSCC therapies and modestly inhibited tumor growth in the xenograft model of HNSCC. To test the chemopreventive potential of STAT3 and epidermal growth factor receptor (EGFR) inhibition, a study administering Guggulipid, a guggulsterone-containing nutraceutical, or erlotinib, an EGFR-targeting tyrosine kinase inhibitor (TKI) to mice treated orally with a carcinogen is currently underway. Our results so far suggest that guggulsterone and honokiol-mediated inhibition of STAT3 and guggulsterone-mediated inhibition of HIF-1 alpha provide a biologic rationale for further clinical investigation of these compounds as complementary and preventive treatments for HNSCC.


Photoswitchable ligands are used to control and study complex biological systems such as folding of proteins and peptides, enzymatic reactions or neuronal signaling. They are typically developed by conjugating photochromic compounds to known ligands so that exposure to light results in the change of the binding affinity of the ligand. Many light-responsive ligands are based on azobenzene, a molecule that undergoes a pronounced change in geometry upon photoisomerization from trans to cis in picoseconds. Currently, photoswitchable ligands are available only to a limited number of targets and their development by rational design is complex. Furthermore, they show low affinity and a relatively small change in binding affinity between the cis and trans conformation. In my PhD work, I aimed at overcoming these shortcomings by establishing an in vitro evolution method to generate light-controlled peptide ligands to targets of choice. Combining the expertise on phage display technology of the Heinis' lab and the knowledge about azobenzene photoswitches of the Wegner's lab, I screened large combinatorial libraries of cyclic peptides containing an azobenzene-based linker for the generation of light controlled ligands. [...]


We reported a general seed-induced strategy for the synthesis of both meso/macroporous ZSM-5 and ZSM-11 (denoted as N-ZSM-5 and N-ZSM-11, respectively) under additive-free, low template/SiO2 ratio (from 0.011 to 0.0014) and seed-assisted hydrothermal conditions. It was found that both N-ZSM-5 and N-ZSM-11 were primarily composed of 20–50 nm oriented nanorods, which showed excellent physicochemical properties, such as high crystallinity, large surface area, auxiliary meso/macroporous structures, and uniform size. When being used in the methanol-to-aromatics reaction (MTA), both Zn/N-ZSM-5 and Zn/N-ZSM-11 exhibited high catalytic efficiencies, as reflected by their far longer lifetimes and higher selectivities for total aromatics than conventional Zn/ZSM-5 and Zn/ZSM-11, due to their unique meso/macroporous structure and ultra-small crystal size that resulted in substantial improvements in the mass-transport properties. This seed-induced strategy inspires new ideas for the design and fabrication of oriented nanorod-assembled hierarchical zeolites with lower cost and good catalytic performance.


ABSTRACT Livestock grazing can affect habitat quality for grasshoppers through effects on food and oviposition site availability, microclimate, and other factors. Because of this, some authors have suggested that grazing programs can be used to help manage pest grasshopper populations. In a 6-yr study, we controlled access of cattle to replicated experimental plots on an Agropyron spicatum/Poa sandbergii pasture to create consistent year-to-year differences in postgrazing plant cover, with resultant affects on microclimate. After sampling grasshoppers multiple times after grazing treatments each summer, we found evidence of between-treatment differences in grasshopper abundance for the entire assemblage during 4 of the 6 yr. Some species, including Melanoplus sanguinipes (perhaps the worse rangeland grasshopper pest in the western United States), tended to be more abundant on ungrazed plots, whereas Melanoplus gladstoni often had greater densities on heavily-grazed plots. The effect of grazing on grasshopper densities in this study was lower in magnitude and less consistent among years than in a study we conducted simultaneously at a nearby site where the vegetation was dominated by the exotic species crested wheatgrass (Agropyron cristatum). Our results generally support proposals that grazing could be used to reduce pest grasshopper densities, although the effectiveness of a particular grazing scheme may vary among sites, years, and grasshopper and vegetation assemblages.


Abstract This article draws from data in a larger qualitative study on the lives of black male teachers in US public urban schools. I examine their schooling experiences as black male youth. By coupling theories of social suffering with life history methodology, this research analyzes how three black male teachers experienced frustration, marginalization, and misery as students. For these participants, academic tracking was a site of social suffering. This suffering persisted into their adult lives as classroom teachers, as they witnessed and attempted to mitigate the struggles of their own black male students. The findings in this study have implications for further research on black male teachers as well as their recruitment and retention in US public schools.


Housing supply plays an important role in the volatility of macroeconomic cycles and the speed with which house prices respond to changes in demand, yet it is understudied in the current literature. In this paper we present and estimate a new model of the supply of residential construction that is consistent with the theoretical treatment of land development and urban growth. This model shows that new housing construction is best described as a function of changes in house prices and costs rather than as a function of the levels of those variables. Previous research that uses the price levels specification has the drawback that a one-time increase in the number of households that raises the level of real house prices leads to a permanent jump in new construction and thus an infinite increase in the stock of housing. The empirical tests of the model support our new specification, which performs better than alternative models in out-of-sample forecasts. Our estimates suggest a fairly moderate response of supply to house price changes. A 10 percent rise in real house prices leads to an 0.8 percent increase in the housing stock, which is accompanied by a temporary 180 percent increase in the average number of quarterly starts, spread over four quarters.