483 research outputs found

    Scattering Theory for Jacobi Operators with Steplike Quasi-Periodic Background

    Full text link
    We develop direct and inverse scattering theory for Jacobi operators with steplike quasi-periodic finite-gap background in the same isospectral class. We derive the corresponding Gel'fand-Levitan-Marchenko equation and find minimal scattering data which determine the perturbed operator uniquely. In addition, we show how the transmission coefficients can be reconstructed from the eigenvalues and one of the reflection coefficients.Comment: 14 page

    Integrating a suicide prevention program into the primary health care network: A field trial study in Iran

    Get PDF
    Objective. To describe and evaluate the feasibility of integrating a suicide prevention program with Primary Health Care services and evaluate if such system can improve screening and identification of depressive disorder, reduce number of suicide attempters, and lower rate of suicide completion. Methodology. This was a quasi-experimental trial in which one community was exposed to the intervention versus the control community with no such exposure. The study sites were two counties in Western Iran. The intervention protocol called for primary care and suicide prevention collaboration at different levels of care. The outcome variables were the number of suicides committed, the number of documented suicide attempts, and the number of identified depressed cases. Results. We identified a higher prevalence of depressive disorders in the intervention site versus the control site (Ăïżœ 2 = 14.8, P < 0.001). We also found a reduction in the rate of suicide completion in the intervention region compared to the control, but a higher prevalence of suicide attempts in both the intervention and the control sites. Conclusion. Integrating a suicide prevention program with the Primary Health Care network enhanced depression and suicide surveillance capacity and subsequently reduced the number of suicides, especially in rural areas. © 2015 Seyed Kazem Malakouti et al

    A reconfigurable stochastic architecture for highly reliable computing

    Full text link
    Mounting concerns over variability, defects and noise motivate a new approach for integrated circuits: the design of stochastic logic, that is to say, digital circuitry that operates on probabilistic signals, and so can cope with errors and uncertainty. Techniques for prob-abilistic analysis are well established. We advocate a strategy for synthesis. In this paper, we present a reconfigurable architecture that implements the computation of arbitrary continuous functions with stochastic logic. We analyze the sources of error: approxima-tion, quantization, and random fluctuations. We demonstrate the ef-fectiveness of our method on a collection of benchmarks for image processing. Synthesis trials show that our stochastic architecture requires less area than conventional hardware implementations. It achieves a large speed up compared to software conventional im-plementations. Most importantly, it is much more tolerant of soft errors (bit flips) than these deterministic implementations

    Parents’ perceived neighborhood safety and children’s cognitive performance:Complexities by race, ethnicity, and cognitive domain

    Get PDF
    Background:Aim: To examine racial/ethnic variations in the effect of parents’ subjective neighborhood safety on children’s cognitive performance. Methods: This cross-sectional study included 10,027 children from the Adolescent Brain Cognitive Development (ABCD) study. The exposure variable was parents’ subjective neighborhood safety. The outcomes were three domains of children’s cognitive performance: general cognitive performance, executive functioning, and learning/memory. We used mixed-effects regression models for data analysis. Results: Overall, parents’ subjective neighborhood safety was positively associated with children’s executive functioning, but not general cognitive performance or learning/memory. Higher parents’ subjective neighborhood safety had a more positive influence on the executive functioning of non-Hispanic White than Asian American children. Higher parents’ subjective neighborhood safety was associated with higher general cognitive performance and learning/memory for non-White children relative to non-Hispanic White children. Conclusion: The race/ethnicity of children moderates the association between neighborhood safety and cognitive performance. This becomes more complicated, as the patterns seem to differ across ethnicity and cognitive domains. It is unknown whether the observed racial/ethnic variations in the effect of neighborhood safety on cognitive performance are neighborhood characteristics such as residential segregation. Addressing neighborhood inequalities is needed if we wish to reduce racial/ethnic inequities in the cognitive development of children

    The Effectiveness of Alcohol Screening and Brief Intervention in Emergency Departments: A Multicentre Pragmatic Cluster Randomized Controlled Trial

    Get PDF
    BACKGROUND: Alcohol misuse is common in people attending emergency departments (EDs) and there is some evidence of efficacy of alcohol screening and brief interventions (SBI). This study investigated the effectiveness of SBI approaches of different intensities delivered by ED staff in nine typical EDs in England: the SIPS ED trial. METHODS AND FINDINGS: Pragmatic multicentre cluster randomized controlled trial of SBI for hazardous and harmful drinkers presenting to ED. Nine EDs were randomized to three conditions: a patient information leaflet (PIL), 5 minutes of brief advice (BA), and referral to an alcohol health worker who provided 20 minutes of brief lifestyle counseling (BLC). The primary outcome measure was the Alcohol Use Disorders Identification Test (AUDIT) status at 6 months. Of 5899 patients aged 18 or more presenting to EDs, 3737 (63·3%) were eligible to participate and 1497 (40·1%) screened positive for hazardous or harmful drinking, of whom 1204 (80·4%) gave consent to participate in the trial. Follow up rates were 72% (n?=?863) at six, and 67% (n?=?810) at 12 months. There was no evidence of any differences between intervention conditions for AUDIT status or any other outcome measures at months 6 or 12 in an intention to treat analysis. At month 6, compared to the PIL group, the odds ratio of being AUDIT negative for brief advice was 1·103 (95% CI 0·328 to 3·715). The odds ratio comparing BLC to PIL was 1·247 (95% CI 0·315 to 4·939). A per protocol analysis confirmed these findings. CONCLUSIONS: SBI is difficult to implement in typical EDs. The results do not support widespread implementation of alcohol SBI in ED beyond screening followed by simple clinical feedback and alcohol information, which is likely to be easier and less expensive to implement than more complex interventions

    Scattering theory with finite-gap backgrounds: Transformation operators and characteristic properties of scattering data

    Full text link
    We develop direct and inverse scattering theory for Jacobi operators (doubly infinite second order difference operators) with steplike coefficients which are asymptotically close to different finite-gap quasi-periodic coefficients on different sides. We give necessary and sufficient conditions for the scattering data in the case of perturbations with finite second (or higher) moment.Comment: 23 page

    Mammography screening: views from women and primary care physicians in Crete

    Get PDF
    Background: Breast cancer is the most commonly diagnosed cancer among women and a leading cause of death from cancer in women in Europe. Although breast cancer incidence is on the rise worldwide, breast cancer mortality over the past 25 years has been stable or decreasing in some countries and a fall in breast cancer mortality rates in most European countries in the 1990s was reported by several studies, in contrast, in Greece have not reported these favourable trends. In Greece, the age-standardised incidence and mortality rate for breast cancer per 100.000 in 2006 was 81,8 and 21,7 and although it is lower than most other countries in Europe, the fall in breast cancer mortality that observed has not been as great as in other European countries. There is no national strategy for screening in this country. This study reports on the use of mammography among middleaged women in rural Crete and investigates barriers to mammography screening encountered by women and their primary care physicians. Methods: Design: Semi-structured individual interviews. Setting and participants: Thirty women between 45–65 years of age, with a mean age of 54,6 years, and standard deviation 6,8 from rural areas of Crete and 28 qualified primary care physicians, with a mean age of 44,7 years and standard deviation 7,0 serving this rural population. Main outcome measure: Qualitative thematic analysis. Results: Most women identified several reasons for not using mammography. These included poor knowledge of the benefits and indications for mammography screening, fear of pain during the procedure, fear of a serious diagnosis, embarrassment, stress while anticipating the results, cost and lack of physician recommendation. Physicians identified difficulties in scheduling an appointment as one reason women did not use mammography and both women and physicians identified distance from the screening site, transportation problems and the absence of symptoms as reasons for non-use. Conclusion: Women are inhibited from participating in mammography screening in rural Crete. The provision of more accessible screening services may improve this. However physician recommendation is important in overcoming women's inhibitions. Primary care physicians serving rural areas need to be aware of barriers preventing women from attending mammography screening and provide women with information and advice in a sensitive way so women can make informed decisions regarding breast caner screening

    Integrating a suicide prevention program into the primary health care network: A field trial study in Iran

    Get PDF
    Objective. To describe and evaluate the feasibility of integrating a suicide prevention program with Primary Health Care services and evaluate if such system can improve screening and identification of depressive disorder, reduce number of suicide attempters, and lower rate of suicide completion. Methodology. This was a quasi-experimental trial in which one community was exposed to the intervention versus the control community with no such exposure. The study sites were two counties in Western Iran. The intervention protocol called for primary care and suicide prevention collaboration at different levels of care. The outcome variables were the number of suicides committed, the number of documented suicide attempts, and the number of identified depressed cases. Results. We identified a higher prevalence of depressive disorders in the intervention site versus the control site (χ2=14.8, P<0.001). We also found a reduction in the rate of suicide completion in the intervention region compared to the control, but a higher prevalence of suicide attempts in both the intervention and the control sites. Conclusion. Integrating a suicide prevention program with the Primary Health Care network enhanced depression and suicide surveillance capacity and subsequently reduced the number of suicides, especially in rural areas
    • 

    corecore