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911.
As drug overdose deaths across the United States continue to rise, there is increasing interest in field testing of illicit substances. This work discusses a paper-based analytical device (idPAD) that can run a library of 12 colorimetric tests at the same time, each detecting different chemical functional groups and materials found in illicit drugs, distractor substances, and cutting agents. The idPAD requires no electricity, costs less than $2 USD, and requires minimal training to operate. The results of the 12 tests form a color barcode which is “read” by comparison to standard images. The accuracy of the idPAD was assessed using samples of heroin, cocaine HCl, crack, and methamphetamine at concentrations of 25%–100% in a lactose matrix, as well as pure lactose. Based on 840 “reads” by three different users, the idPAD showed 95% sensitivity and 100% specificity for detecting these drugs; the most common error was mistaking cocaine HCl for crack or crack for cocaine HCl. In a second step, samples of heroin, cocaine, and methamphetamine (n = 30) and distractor substances (pharmaceuticals, cutting agents, and other illicit drugs, n = 64) were tested by two readers, yielding a sensitivity of 100% and specificity of 97%. Targeted substances were detected reliably at 55–180 μg/lane, and the idPAD was found to be stable for at least 3 months when stored at room temperature. The library approach used in the idPAD may provide the accuracy and robustness necessary for a presumptive field drug test.  相似文献   
912.
Understanding the degree and pattern of shrinkage undergone by bone when subjected to heating is crucial to accurately deduce a biological profile from incinerated remains. X-ray microtomography (micro-CT) enables a nondestructive insight into hard tissue structural changes, while allowing for an accurate documentation of volumetric and trabecular shrinkage. Sheep ribs were experimentally burned at temperatures between 400 and 1000°C in 100°C increments and their volumetric shrinkage was calculated. Observed shrinkage ranged from 14.0% at 400°C to 45.5% at 1000°C. Bones burned at temperatures up to 600°C showed no significant difference, whereas the 700 and 800°C samples exhibited higher shrinkage. Bones burnt at 900 and 1000°C showed significantly higher shrinkage than the other temperature groups. Findings signify the potential of micro-CT in research on the effects of factors such as diagenesis or burning on the bone density, morphology and microarchitecture.  相似文献   
913.
We use 10 years of California administrative data with a regression kink design to estimate the causal impacts of benefits in the first state-level paid family leave program for women with earnings near the maximum benefit threshold. We find no evidence that a higher weekly benefit amount (WBA) increases leave duration or leads to adverse future labor market outcomes for this group. In contrast, we document that a rise in the WBA leads to an increased likelihood of returning to the pre-leave firm (conditional on any employment) and of making a subsequent paid family leave claim.  相似文献   
914.
Scientific research has made major contributions to adolescent health by providing insights into factors that influence it and by defining ways to improve it. However, US adolescent sexual and reproductive health policies—particularly sexuality health education policies and programs—have not benefited from the full scope of scientific understanding. From 1998 to 2009, federal funding for sexuality education focused almost exclusively on ineffective and scientifically inaccurate abstinence-only-until-marriage (AOUM) programs. Since 2010, the largest source of federal funding for sexual health education has been the “tier 1” funding of the Office of Adolescent Health’s Teen Pregnancy Prevention Initiative. To be eligible for such funds, public and private entities must choose from a list of 35 programs that have been designated as “evidence-based” interventions (EBIs), determined based on their effectiveness at preventing teen pregnancies, reducing sexually transmitted infections, or reducing rates of sexual risk behaviors (i.e., sexual activity, contraceptive use, or number of partners). Although the transition from primarily AOUM to EBI is important progress, this definition of evidence is narrow and ignores factors known to play key roles in adolescent sexual and reproductive health. Important bodies of evidence are not treated as part of the essential evidence base, including research on lesbian, gay, bisexual, transgender, queer, and questioning (LGBTQ) youth; gender; and economic inequalities and health. These bodies of evidence underscore the need for sexual health education to approach adolescent sexuality holistically, to be inclusive of all youth, and to address and mitigate the impact of structural inequities. We provide recommendations to improve US sexual health education and to strengthen the translation of science into programs and policy.  相似文献   
915.
Although there is growing recognition of the problem of dating violence, little is known about how it unfolds among young adolescents who are just beginning to date. This study examined classes (subgroups) and transitions between classes over three time points based on dating violence, bullying, and sexual harassment perpetration and victimization experienced by youth. The sample was ethnically diverse, consisting of 795 seventh-grade students from schools that were part of a multi-site, longitudinal evaluation of a dating violence initiative (50 % female; 27 % White, 32 % African American, 25 % Latino, 16 % other or multiple races). Results from latent transition analyses revealed five classes of students with distinct behavioral profiles: multi-problem (victimization and perpetration), bullying and sexual harassment (victimization and perpetration), bullying (victimization and perpetration) and sexual harassment (victimization only), bullying (victimization and perpetration), and a least problem group. The majority of classes were characterized by reports of both perpetration and victimization for at least one behavior. Girls were more likely to be in the less problematic classes. Class membership was fairly stable across the three time points. When students transitioned to a different class, the shift was most often from a more problematic to a less problematic class, particularly for girls. The findings support understanding dating violence within a dynamic, developmental process that recognizes related behaviors within and across individuals. Overall, the findings highlight the utility of person-oriented approaches to enhance our understanding of longitudinal profiles and transitions over time for dating violence and related behaviors.  相似文献   
916.
917.
ABSTRACT

Each Passover since 2009, hundreds of East African asylum seekers and Israeli activists have gathered for ‘Refugee Seder’, a public event to support Sudanese and Eritrean communities in Israel. Featuring a ceremonial seder meal, storytelling, speeches, and a dance party, Refugee Seder draws on age-old Jewish rituals and contemporary global black pop musics to symbolize Africans as members of the Israeli national collective. This article explores Refugee Seder’s modified commemorative practices, which engage dual narratives of Jewish nationalism and cultural cosmopolitanism. I show how seder rituals enable African participants to temporarily embody a Jewish spiritual identity, and how black pop musics help publicly reframe Africans’ ‘blackness’ as a cultural asset instead of a political liability. Ultimately, I argue that Refugee Seder distills larger ideologies of identity and belonging that are deeply rooted in Israeli collective consciousness, and which shape the trajectories of ‘refugee issue’ politics and policy-making.  相似文献   
918.
919.
920.
As populations increase and droughts intensify, water providers are using tools such as persuasive messaging to decrease residential water use. However, district-led messaging campaigns are rarely informed by psychological science, evaluated for effectiveness, or strategically disseminated. In collaboration with a water district, we report a field experiment among single-family households using persuasive messaging based on the information-motivation-behavioral skills model (IMB). We randomly assigned 10,000 households to receive different mailings and measured household water use. All messaging reduced water consumption relative to the control. On average, water use dropped 0.68 hundred cubic feet (HCF) (509 gallons) per household in the first month. Had all 10,000 single-family, occupied, non-agricultural residences been mailed the IMB messaging, more than five million gallons would have been saved in the first month. The effects declined but persisted for approximately three months and were three to six times greater in households with high water use (75th to 90th percentiles) relative to average water use. These findings suggest that combining message elements from the IMB model can reduce residential water use and that targeting high-use households is particularly cost-effective.  相似文献   
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