Charge control approach to characterization of field effect transistors with application to low level switching

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A facial expression for anxiety.

Anxiety and fear are often confounded in discussions of human emotions. However, studies of rodent defensive reactions under naturalistic conditions suggest anxiety is functionally distinct from fear. Unambiguous threats, such as predators, elicit flight from rodents (if an escape-route is available), whereas ambiguous threats (e.g., the odor of a predator) elicit risk assessment behavior, which is associated with anxiety as it is preferentially modulated by anti-anxiety drugs. However, without human evidence, it would be premature to assume that rodent-based psychological models are valid for humans. We tested the human validity of the risk assessment explanation for anxiety by presenting 8 volunteers with emotive scenarios and asking them to pose facial expressions. Photographs and videos of these expressions were shown to 40 participants who matched them to the scenarios and labeled each expression. Scenarios describing ambiguous threats were preferentially matched to the facial expression posed in response to the same scenario type. This expression consisted of two plausible environmental-scanning behaviors (eye darts and head swivels) and was labeled as anxiety, not fear. The facial expression elicited by unambiguous threat scenarios was labeled as fear. The emotion labels generated were then presented to another 18 participants who matched them back to photographs of the facial expressions. This back-matching of labels to faces also linked anxiety to the environmental-scanning face rather than fear face. Results therefore suggest that anxiety produces a distinct facial expression and that it has adaptive value in situations that are ambiguously threatening, supporting a functional, risk-assessing explanation for human anxiet

The emergence of resistance to the benzimidazole anthlemintics in parasitic nematodes of livestock is characterised by multiple independent hard and soft selective sweeps

Anthelmintic resistance is a major problem for the control of parasitic nematodes of livestock and of growing concern for human parasite control. However, there is little understanding of how resistance arises and spreads or of the “genetic signature” of selection for this group of important pathogens. We have investigated these questions in the system for which anthelmintic resistance is most advanced; benzimidazole resistance in the sheep parasites Haemonchus contortus and Teladorsagia circumcincta. Population genetic analysis with neutral microsatellite markers reveals that T. circumcincta has higher genetic diversity but lower genetic differentiation between farms than H. contortus in the UK. We propose that this is due to epidemiological differences between the two parasites resulting in greater seasonal bottlenecking of H. contortus. There is a remarkably high level of resistance haplotype diversity in both parasites compared with drug resistance studies in other eukaryotic systems. Our analysis suggests a minimum of four independent origins of resistance mutations on just seven farms for H. contortus, and even more for T. circumincta. Both hard and soft selective sweeps have occurred with striking differences between individual farms. The sweeps are generally softer for T. circumcincta than H. contortus, consistent with its higher level of genetic diversity and consequent greater availability of new mutations. We propose a model in which multiple independent resistance mutations recurrently arise and spread by migration to explain the widespread occurrence of resistance in these parasites. Finally, in spite of the complex haplotypic diversity, we show that selection can be detected at the target locus using simple measures of genetic diversity and departures from neutrality. This work has important implications for the application of genome-wide approaches to identify new anthelmintic resistance loci and the likelihood of anthelmintic resistance emerging as selection pressure is increased in human soil-transmitted nematodes by community wide treatment programs

Diabetic retinopathy in sub-Saharan Africa: meeting the challenges of an emerging epidemic

BACKGROUND: Sub-Saharan Africa faces an epidemic of diabetes. Diabetes causes significant morbidity including visual loss from diabetic retinopathy, which is largely preventable. In this resource-poor setting, health systems are poorly organized to deliver chronic care with multiple system involvement. The specific skills and resources needed to manage diabetic retinopathy are scarce. The costs of inaction for individuals, communities and countries are likely to be high. DISCUSSION: Screening for and treatment of diabetic retinopathy have been shown to be effective, and cost-effective, in resource-rich settings. In sub-Saharan Africa, clinical services for diabetes need to be expanded with the provision of effective, integrated care, including case-finding and management of diabetic retinopathy. This should be underpinned by a high quality evidence base accounting for differences in diabetes types, resources, patients and society in Africa. Research must address the epidemiology of diabetic retinopathy in Africa, strategies for disease detection and management with laser treatment, and include health economic analyses. Models of care tailored to the local geographic and social context are most likely to be cost effective, and should draw on experience and expertise from other continents. Research into diabetic retinopathy in Africa can drive the political agenda for service development and enable informed prioritization of available health funding at a national level. Effective interventions need to be implemented in the near future to avert a large burden of visual loss from diabetic retinopathy in the continent. SUMMARY: An increase in visual loss from diabetic retinopathy is inevitable as the diabetes epidemic emerges in sub-Saharan Africa. This could be minimized by the provision of case-finding and laser treatment, but how to do this most effectively in the regional context is not known. Research into the epidemiology, case-finding and laser treatment of diabetic retinopathy in sub-Saharan Africa will highlight a poorly met need, as well as guide the development of services for that need as it expands

Determinants of severity and progression of diabetic retinopathy in Southern Malawi

Background Sub-Saharan Africa faces an epidemic of diabetes. The prevalence and incidence of sight threatening diabetic retinopathy in developed countries and associations between systemic factors, including glycaemic control, blood pressure and blood lipid levels, are well documented. In contrast the epidemiological literature from sub-Saharan Africa is sparse. In this resource-poor setting, population-specific variables such as a high burden of infectious disease and anaemia are likely to affect the spectrum of pathology encountered. I aimed to investigate the prevalence, incidence and progression of diabetic retinopathy in Southern Malawi, to investigate the risk factors for diabetic retinopathy severity and progression in this population and to characterise endothelial function in Southern Malawian subjects with diabetes. Methods I established the Malawi Diabetic Retinopathy Study, a 24 month prospective cohort study. Subjects were systematically sampled from two hospital-based, primary care diabetes clinics. Visual acuity, glycaemic control, systolic blood pressure, HIV status, urine albumin–creatinine ratio, and haemoglobin and serum lipid levels were assessed. Retinopathy was graded at an accredited reading centre using modified Wisconsin grading of four-field mydriatic photographs. Additionally, in order to investigate DR progression at five years, a cohort of subjects recruited to a cross-sectional study of diabetes complications in 2007 were traced and assessed. In a nested case-control study, serum markers of endothelial dysfunction and pulse amplitude tonometry were measured in a subset of subjects from the main cohort plus subjects without diabetes. Results 357 subjects were recruited to the 24 month cohort study. At baseline 13.4% subjects were HIV-positive and 15.1% were anaemic. Baseline prevalence rates of any retinopathy, sight threatening diabetic retinopathy and proliferative retinopathy were 50.1% (95% CI 44.9–55.3), 29.4% (95% CI 24.7–34.1) and 7.3% (95% CI 4.6–10.0), respectively. Cumulative incidence at 2 years of sight threatening diabetic retinopathy for subjects with level 10 (no retinopathy), level 20 (background) and level 30 at baseline was 2.7% (95% CI 0.1-5.3), 27.3% (16.4-38.2) and 25.0% (0-67.4), respectively. In a multivariate logistic analysis, 2 step progression of diabetic retinopathy at 2 years was associated with HbA1c (odds ratio 1.27, 95%CI 1.12-1.45), baseline grade of DR (1.39, 1.02-1.91) and HIV infection (OR 0.16, 0.03-0.78). At 2 years, rates of progression to visual loss were: ≥15 letters lost in 17 subjects (5.8%), moderate visual impairment (<60 letters) in 3 subjects (1.0%), severe visual impairment (<50 letters) in 5 subjects (1.7%). The five year incidence of sight threatening diabetic retinopathy in subjects recruited to the 2007 cross sectional study, for those with level 10 and level 20 retinopathy at baseline, was 19.4% (11.3-27.4) and 81.3% (62.1-100), respectively. In the case control study of endothelial function higher serum VEGF and E-selectin were associated with having diabetes in multivariate regression. Serum VCAM-1 was associated with death in multivariate regression. Conclusions I report the first cohort study of diabetic retinopathy from sub-Saharan Africa. I found a prevalence of sight threatening diabetic retinopathy, in subjects attending diabetes clinics, approximately 3 times that reported in recent European studies and a prevalence of proliferative retinopathy approximately 10 times higher. Progression to sight threatening diabetic retinopathy occurred approximately 3 times more frequently than reported in Europe. The negative association of HIV infection with retinopathy progression is a new finding. I report the first evidence from sub-Saharan Africa of endothelial dysfunction in subjects with diabetes and of an association between levels of endothelial biomarkers and mortality in these subjects. Results presented in this thesis highlight the urgent need for provision of services for retinopathy detection and management to avoid a large burden of vision loss

Elite images and foreign policy outcomes: a study of Norway

(print) xviii, 179 p. ; 23 cm"A publication of the Mershon Center for Education in National Security."Introduction 3 -- Foreign policy analysis 3 -- The strategic image as an analytical concept 4 -- Data sources and problems 5 -- The nature of a strategic image 6 -- The utility of image analysis 7 -- Chapter One : Norwegian Foreign Policy in Perspective 13 -- A country profile 13 -- An overview of Norway in world affairs 17 -- Summary 30 -- Chapter Two : The Emergence of New Axioms in Norwegian Foreign Policy 47 -- World War II and the London government 47 -- The emergence of new concepts 50 -- Norway's relations with Norden in World War II 55 -- Norwegian-Soviet Relations 61 -- Norway and the United Nations Organization 64 -- Chapter Three : The Search for Security : Bridgebuilding in the United Nations 75 -- The strategic image at the beginning of the postwar period 75 -- The policy of bridgebuilding 79 -- Chapter Four : The Search for Security : Scandinavia and the Atlantic 101 -- The security problem in perspective 101 -- Prelude to the Scandinavian defense negotiations 103 -- The position of Sweden and Denmark 105 -- The period of the Scandinavian defense investigation 110 -- The period of the Scandinavian political negotiations 117 -- The move toward the Atlantic Pact 124 -- Chapter Five : The Trend of Norwegian Foreign Policy 143 -- The evolution of the Norwegian strategic image 143 -- Norwegian consideration of a Scandinavian alternative 147 -- Conclusion 159 -- Appendixes 165 -- Bibliographic note 169 -- Index 17

Source Mechanisms of Laboratory Earthquakes During Fault Nucleation and Formation

Acknowledgments The authors thank Emily Butcher for sample preparation and Peter Ibemesi for assistance during the laboratory experiments. The authors greatly appreciate the efforts of one anonymous reviewer and Jessica McBeck in significantly improving the quality of this study.Peer reviewedPublisher PD

Routine measurement of outcomes in Australia's public sector mental health services

OBJECTIVE: This paper describes the Australian experience to date with a national 'roll out' of routine outcome measurement in public sector mental health services. METHODS: Consultations were held with 123 stakeholders representing a range of roles. RESULTS: Australia has made an impressive start to nationally implementing routine outcome measurement in mental health services, although it still has a long way to go. All States/Territories have established data collection systems, although some are more streamlined than others. Significant numbers of clinicians and managers have been trained in the use of routine outcome measures, and thought is now being given to ongoing training strategies. Outcome measurement is now occurring 'on the ground'; all States/Territories will be reporting data for 2003–04, and a number have been doing so for several years. Having said this, there is considerable variability regarding data coverage, completeness and compliance. Some States/Territories have gone to considerable lengths to 'embed' outcome measurement in day-to-day practice. To date, reporting of outcome data has largely been limited to reports profiling individual consumers and/or aggregate reports that focus on compliance and data quality issues, although a few States/Territories have begun to turn their attention to producing aggregate reports of consumers by clinician, team or service. CONCLUSION: Routine outcome measurement is possible if it is supported by a co-ordinated, strategic approach and strong leadership, and there is commitment from clinicians and managers. The Australian experience can provide lessons for other countries

Smart Knowledge Capture for Developing Adaptive Management Systems

In this paper we describe how a welldesigned Spatial Decision Support System (SDSS) may facilitate initial (immediate) decision making, while establishing a robust foundation and framework for improving effectiveness over time as new data and knowledge becomes available. \u27Smart Knowledge Capture\u27 is a set of methods for rapidly developing a strong SDSS for adaptive management. We review some of the MIS tools used in Smart Knowledge Capture: multicriteria decision analysis (MCDA) tools, online surveys, online knowledge portals, ontology systems, and describe the architecture of an SDSS that stores and utilizes this knowledge. We illustrate these concepts using our recent work supporting the development of a revised desert tortoise recovery plan

Posterior segment eye disease in sub-Saharan Africa: review of recent population-based studies.

OBJECTIVE: To assess the burden of posterior segment eye diseases (PSEDs) in sub-Saharan Africa (SSA). METHODS: We reviewed published population-based data from SSA and other relevant populations on the leading PSED, specifically glaucoma, diabetic retinopathy and age-related macular degeneration, as causes of blindness and visual impairment in adults. Data were extracted from population-based studies conducted in SSA and elsewhere where relevant. RESULTS: PSEDs, when grouped or as individual diseases, are a major contributor to blindness and visual impairment in SSA. PSED, grouped together, was usually the second leading cause of blindness after cataract, ranging as a proportion of blindness from 13 to 37%. CONCLUSIONS: PSEDs are likely to grow in importance as causes of visual impairment and blindness in SSA in the coming years as populations grow, age and become more urban in lifestyle. African-based cohort studies are required to help estimate present and future needs and plan services to prevent avoidable blindness