370 research outputs found
A gamma- and X-ray detector for cryogenic, high magnetic field applications
As part of an experiment to measure the spectrum of photons emitted in
beta-decay of the free neutron, we developed and operated a detector consisting
of 12 bismuth germanate (BGO) crystals coupled to avalanche photodiodes (APDs).
The detector was operated near liquid nitrogen temperature in the bore of a
superconducting magnet and registered photons with energies from 5 keV to 1000
keV. To enlarge the detection range, we also directly detected soft X-rays with
energies between 0.2 keV and 20 keV with three large area APDs. The
construction and operation of the detector is presented, as well as information
on operation of APDs at cryogenic temperatures
Predictors and Consequences of Prescription Opioid Use in Women Living With and Without HIV: 20-Year Follow-Up
Objective: To examine predictors and consequences of prescription opioid use among a cohort of women living with HIV (WLWH) and women without HIV from 2000 to 2019. Materials and Methods: The Women's Interagency HIV Study is a multisite, prospective cohort study. Cumulative proportion of visits with prescription opioid use was categorized as follows: minimal (0%-9%), intermediate (10%-39%), and chronic (>40%). Logistic regression examined independent predictors, and proportional hazards regression estimated unadjusted and adjusted hazards of all-cause mortality, comparing intermediate and chronic prescription opioid use with minimal use. Results: Annual prevalence of prescription opioid use significantly increased from 12.6% to 19.3% from 2000 to 2019 (p < 0.0001). Prescription opioid use was minimal in 75%, intermediate in 16%, and chronic in 9% of women. WLWH had 56% higher odds of chronic prescription opioid use compared with women without HIV. Even after adjusting for quality-of-life scores including ratings of pain, women with intermediate and chronic prescription opioid use had greater odds of being sexual minorities (lesbian or bisexual), unemployed, and were more likely to report benzodiazepine and nonprescription substance use compared with those with minimal use. Intermediate and chronic prescription opioid use were each associated with an almost 1.5-fold increased risk of all-cause mortality. Conclusions: Despite federally mandated opioid prescribing guidelines, prescription opioid use and related mortality significantly increased in women experiencing physical and psychosocial vulnerabilities. The higher mortality rate found among prescription opioid users may reflect the many underlying chronic medical and psychosocial conditions for which these opioids were prescribed, as well as complications of opioids themselves. Findings underscore the need for non-opioid and nonpharmacological interventions for chronic pain, particularly in sexual minorities and WLWH. Avoiding concurrent use of opioids with benzodiazepines and nonprescription drugs might reduce mortality
Nonperturbative renormalization group approach to frustrated magnets
This article is devoted to the study of the critical properties of classical
XY and Heisenberg frustrated magnets in three dimensions. We first analyze the
experimental and numerical situations. We show that the unusual behaviors
encountered in these systems, typically nonuniversal scaling, are hardly
compatible with the hypothesis of a second order phase transition. We then
review the various perturbative and early nonperturbative approaches used to
investigate these systems. We argue that none of them provides a completely
satisfactory description of the three-dimensional critical behavior. We then
recall the principles of the nonperturbative approach - the effective average
action method - that we have used to investigate the physics of frustrated
magnets. First, we recall the treatment of the unfrustrated - O(N) - case with
this method. This allows to introduce its technical aspects. Then, we show how
this method unables to clarify most of the problems encountered in the previous
theoretical descriptions of frustrated magnets. Firstly, we get an explanation
of the long-standing mismatch between different perturbative approaches which
consists in a nonperturbative mechanism of annihilation of fixed points between
two and three dimensions. Secondly, we get a coherent picture of the physics of
frustrated magnets in qualitative and (semi-) quantitative agreement with the
numerical and experimental results. The central feature that emerges from our
approach is the existence of scaling behaviors without fixed or pseudo-fixed
point and that relies on a slowing-down of the renormalization group flow in a
whole region in the coupling constants space. This phenomenon allows to explain
the occurence of generic weak first order behaviors and to understand the
absence of universality in the critical behavior of frustrated magnets.Comment: 58 pages, 15 PS figure
Food insecurity is associated with anxiety, stress, and symptoms of posttraumatic stress disorder in a cohort of women with or at risk of HIV in the United States
Background: Food insecurity, which disproportionately affects marginalized women in the United States, is associated with depressive symptoms. Few studies have examined relations of food insecurity with other mental health outcomes. Objective: The aim of this study was to investigate the associations of food insecurity with symptoms of generalized anxiety disorder (GAD), stress, and posttraumatic stress disorder (PTSD) in the Women's Interagency HIV Study (WIHS), a prospective cohort study of women with or at risk of HIV in the United States. Methods: Participants were 2553 women with or at risk of HIV, predominantly African American/black (71.6%). Structured questionnaires were conducted during April 2013-March 2016 every 6 mo. Food security (FS) was the primary predictor, measured using the Household Food Security Survey Module. We measured longitudinal outcomes for GAD (GAD-7 score and a binary GAD-7 screener for moderate-to-severe GAD). Only cross-sectional data were available for outcomes measuring perceived stress (PSS-10 score) and PTSD (PCL-C score and a binary PCL-C screener for PTSD). We examined associations of FS with the outcomes through use of multivariable linear and logistic regression, including lagged associations with GAD outcomes. Results: After adjusting for sociodemographic and health-related factors including HIV serostatus, current marginal, low, and very low FS were associated with increasingly higher GAD-7 scores, and with 1.41 (95% CI: 1.10, 1.80; P < 0.01), 2.03 (95% CI: 1.59, 2.61; P < 0.001), and 3.23 (95% CI: 2.43, 4.29; P < 0.001) times higher odds of screening positive for moderate-to-severe GAD, respectively. Low and very low FS at the previous visit (6 mo earlier) were independently associated with GAD outcomes at current visit. Associations of FS with PSS-10 and PCL-C scores exhibited similar dose-response relations. Very low FS was associated with 1.93 (95% CI: 1.15, 3.24; P < 0.05) times higher odds of screening positive for PTSD. Conclusions: Food insecurity may be associated with a range of poor mental health outcomes among women in the United States with or at risk of HIV
Socioeconomic, Psychosocial, and Clinical Factors Associated with Employment in Women with HIV in the United States: A Correlational Study
Employment is a social determinant of health, and women living with HIV (WLWH) are often underemployed. This correlational study examined the socioeconomic, psychosocial, and clinical factors associated with employment among WLWH (n = 1,357) and women at risk for HIV (n = 560). Descriptive and inferential statistics were used to evaluate factors associated with employment status. Employment was associated (p ≤.05) with better socioeconomic status and quality of life (QOL), less tobacco and substance use, and better physical, psychological, and cognitive health. Among WLWH, employment was associated (p ≤.05) with improved adherence to HIV care visits and HIV RNA viral suppression. Using multivariable regression modeling, differences were found between WLWH and women at risk for HIV. Among WLWH, household income, QOL, education, and time providing childcare remained associated with employment in adjusted multivariable analyses (R2=.272, p <.001). A better understanding of the psychosocial and structural factors affecting employment is needed to reduce occupational disparities among WLWH
Impact of Austria's 2009 trans fatty acids regulation on all-cause, cardiovascular and coronary heart disease mortality
Background: Unhealthy diet, especially consumption of trans fatty acids (TFAs), is a known risk factor for cardiovascular disease (CVD), a leading cause of death in Austria. In 2009, Austria introduced a law regulating the content of TFAs in foods. The aim of this study was to assess the impact of the TFA regulation on CVD-related outcomes.Methods: The study evaluated the TFA regulation as an intervention in a natural experiment. Two study periods were assessed: pre-intervention (1995-2009) and post-intervention (2010-14). The study compared the age-standardized death rates per 100 000 population for CVD outcomes with those of a 'synthetic' international comparator population, created from data of OECD countries where TFA regulation has not been implemented, but where the population is otherwise comparable.Results: There was a continuous decrease in CVD-related mortality throughout the study period in both the synthetic international comparator population, as well as in the adult Austrian population, with no significant change in this trend observed as an effect of TFA regulation.Conclusions: Whilst the results are counterintuitive, given the established link between TFA consumption and an increased risk of CVD, there are many possible explanations: high prevalence of tobacco smoking, changes in TFA content in foods due to international guidance as opposed to formal regulation and a beneficial impact of TFA regulation on sub-groups of the population that might not be detected with nationally aggregated data. However, reduction in TFAs should still be considered an important part of risk factor reduction for CVD and other non-communicable diseases
The Concept of Power in the Analysis of Organisations with Social and Political Goals
I propose a theoretical framework for examining the extent to which organisations with social and political goals (OSPs) empower (or disempower) participants as effective political citizens. Theories of power – including behaviouralism, Structuration and Foucauldian notions – are drawn on to illuminate relevant aspects of organisational life. Together they account for the role of individuals, rules and processes, procedure and administration, culture and practice, techniques of organisation and communication. The intention is to shed light on how groups or individuals are empowered or otherwise and provides a basis, where necessary, for challenging existing structures and practices in the name of greater empowerment
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