2,349 research outputs found
Field-induced paramagnons at the metamagnetic transition in Ca1.8Sr0.2RuO4
The magnetic excitations in Ca1.8Sr0.2RuO4 were studied across the
metamagnetic transition and as a function of temperature using inelastic
neutron scattering. At low temperature and low magnetic field the magnetic
response is dominated by a complex superposition of incommensurate
antiferromagnetic fluctuations. Upon increasing the magnetic field across the
metamagnetic ransition, paramagnon and finally well-defined magnon scattering
is induced, partially suppressing the incommensurate signals. The high-field
phase in Ca1.8Sr0.2RuO4 has, therefore, to be considered as an intrinsically
ferromagnetic state stabilized by the magnetic field
Multiple social identities enhance health post-retirement because they are a basis for giving social support
This is the final version of the article. Available from the publisher via the DOI in this record.We examine the extent to which multiple social identities are associated with enhanced health and well-being in retirement because they provide a basis for giving and receiving social support. Results from a cross-sectional study show that retirees (N = 171) who had multiple social identities following (but not prior to) retirement report being (a) more satisfied with retirement, (b) in better health, and (c) more satisfied with life in general. Furthermore, mediation analyses revealed an indirect path from multiple social identities to greater satisfaction with retirement and better health through greater provision, but not receipt, of social support to others. These findings are the first to point to the value of multiple group membership post-retirement as a basis for increased opportunities to give meaningful support to others. We discuss the theoretical and practical implications for the management of multiple identities in the process of significant life transitions such as retirement.This work was supported by three grants from the
Australian Research Council awarded to JJ (FT110100238), CH
(DP160102514), and AH (FL110100199
Social group memberships in retirement are associated with reduced risk of premature death: evidence from a longitudinal cohort study.
This is the final version of the article. Available from [publisher] via the DOI in this record.OBJECTIVES: Retirement constitutes a major life transition that poses significant challenges to health, with many retirees experiencing a precipitous decline in health status following retirement. We examine the extent to which membership in social groups following retirement determines quality of life and mortality. DESIGN: The longitudinal impact of the number of social group memberships before and after the transition to retirement was assessed on retirees' quality of life and risk of death 6 years later. SETTING: Nationally representative cohort study of older adults living in England. PARTICIPANTS: Adults who underwent the transition to retirement (N=424). A matched control group (N=424) of participants who had comparable demographic and health characteristics at baseline but did not undergo the transition to retirement were also examined. OUTCOME MEASURES: Analyses examined participants' quality of life and mortality during a period of 6 years. RESULTS: Retirees who had two group memberships prior to retirement had a 2% risk of death in the first 6 years of retirement if they maintained membership in two groups, a 5% risk if they lost one group and a 12% risk if they lost both groups. Furthermore, for every group membership that participants lost in the year following retirement, their experienced quality of life 6 years later was approximately 10% lower. These relationships are robust when controlling for key sociodemographic variables (age, gender, relationship status and socioeconomic status prior to retirement). A comparison with a matched control group confirmed that these effects were specific to those undergoing the transition to retirement. The effect of social group memberships on mortality was comparable to that of physical exercise. CONCLUSIONS: Theoretical implications for our understanding of the determinants of retiree quality of life and health, and practical implications for the support of people transitioning from a life of work to retirement are discussed.This research was supported by two grants from the Australian Research Council awarded to JJ (FT110100238) and SAH (FL110100199). The funding body did not play any role in the research design; in the collection, analysis, and interpretation of data; in the writing of the manuscript; or in the decision to submit the manuscript for publication
Reining in the Web's Inconsistencies with Site Policy
Over the years, browsers have adopted an ever-increasing number of client-enforced security policies deployed through HTTP headers. Such mechanisms are fundamental for web application security, and usually deployed on a per-page basis. This, however, enables inconsistencies, as different pages within the same security boundaries (in form of origins or sites) can express conflicting security requirements. In this paper, we formalize inconsistencies for cookie security attributes, CSP, and HSTS, and then quantify the magnitude and impact of inconsistencies at scale by crawling 15,000 popular sites. We show that numerous sites endanger their own security by omission or misconfiguration of the aforementioned mechanisms, which lead to unnecessary exposure to XSS, cookie theft, and HSTS deactivation. We then use our data to analyse to which extent the recent Origin Policy proposal can fix the problem of inconsistencies. Unfortunately, we conclude that the current Origin Policy design suffers from major shortcomings which limit its practical applicability to address security inconsistencies while catering to the need of real-world sites. Based on these insights, we propose Site Policy, designed to overcome Origin Policy's shortcomings and make any insecurity explicit. We make a prototype implementation of Site Policy publicly available, along with a supporting toolchain for initial policy generation, security analysis, and test deployment
C\u3csub\u3e3\u3c/sub\u3e Perennial Grass Dominates Mixed C\u3csub\u3e3\u3c/sub\u3e/C\u3csub\u3e4\u3c/sub\u3e Grasslands After Invasion by a C\u3csub\u3e3\u3c/sub\u3e Woody Sprouter
Honey mesquite (Prosopis glandulosa) encroachment has resulted in decreased C4 mid-grass production and increased C3 mid-grass in the Southern Great Plains of the US. Woody legumes have had similar effects in Africa, Australia, and South America. Prosopis initially facilitates Texas wintergrass (Nassella leucotricha) growth under canopies, in part because N-fixation by this woody legume enriches subcanopy soils, favoring C3 species. As stand density increases, Nassella extends into interspaces between trees as well. Here we report Nassella responses in several studies that either reduced Prosopis to indirectly impact Nassella or treated Nassella directly. In a 9-year study following mechanical top-kill of Prosopis, Nassella increased production for the first 3 years before slowly declining to pre-treatment levels. C4 mid-grass production increased, but was limited to only a third of its potential by drought and Prosopis regrowth. Following a root-killing treatment of Prosopis, Nassella production and total herbaceous production were greater in treated than untreated intercanopy and subcanopy microsites 1-yr post-treatment. Nassella and perennial grass production declined in treated microsites 2-yrs post-treatment; however, total herbaceous production remained greater in treated than untreated microsites due to increased annual forb production. Targeted grazing reduced Nassella cover and reproduction, but increased bare ground. Multiple-stemmed Prosopis with low-hanging limbs protected Nassella, thus limiting targeted grazing success when trees were not removed. The Prosopis/Nassella state appears to be resistant to change and may permanently limit transition back to C4 grassland unless Prosopis is root-killed, though our results indicate that even root-killing Prosopis does not guarantee an immediate increase in C4 production. If so, managing Prosopis height and canopy cover, C:N ratios of the vegetative layer, and grazing Nassella during peak production and nutritional quality may allow profitable production until anthropogenic or natural processes result in large scale mortality of the Prosopis overstory
Aplicação de sensor óptico de pH, de baixo custo, baseado em pet/pani para utilização em água natural.
Desenvolvimento de sensor óptico de baixo custo para o monitoramento de pH baseado em filmes finos de polianilina.
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