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There is growing interest in the use of unconditional cash transfers as a means to alleviate poverty, yet little is known about the effects of such transfers in the U.S. This paper reports on the results of a randomized controlled study of a one-time $1,000 unconditional cash transfer in May 2020 to families with low incomes in 12 U.S. states. The families were receiving, or had recently received, Supplemental Nutrition Assistance Program benefits. We examine the impact of the cash transfer on five pre-registered outcomes (material hardship, mental health, parenting, child behavior, partner relationships) and several secondary outcomes (hardship avoidance, consumption, employment, benefit use). We find no statistically significant effects (powered to detect effects of 0.09 standard deviations) of the cash transfer on any outcomes for the full sample. In pre-specified exploratory analyses, we find significant reductions in material hardship (-0.17 standard deviations) among families with less than $500 of earnings in the previous month, roughly the bottom 50 percent of monthly earnings for the study sample.  相似文献   
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Global crises have heightened policy uncertainties and efforts to address global climate change. Limited evidence exists in the literature on geopolitical risk's direct and indirect roles in addressing global emissions. In this study, we examine whether geopolitical risk could impede or facilitate efforts to attain a net-zero emissions target through energy transition using panel data for 42 countries from 1990 to 2020. Various econometric techniques were applied in this study to present robust findings and reliable conclusions. Estimates from the Driscoll-Kraay, Lewbel two-stage least squares and method of moment regression techniques consistently showed that countries' geopolitical risk directly increases emissions (total greenhouse gas, carbon, methane, and nitrous oxide). At the same time, energy transition, measured with renewable energy consumption, mitigates these emissions. In addition, evidence from the partial linear functional-coefficient model technique indicates that renewable energy consumption consistently mitigates emissions when geopolitical is minimal (at a minimum and mean level). However, the role of renewable energy consumption in reducing emissions becomes weaker when geopolitical risk is heightened—thus, when geopolitical risk reaches its maximum level. We recommend that efforts to sustain renewable energy transition and maintain geopolitical stability are vital for achieving net-zero emissions and climate change mitigation.  相似文献   
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One of the most fundamental factors related to psychological well being across the lifespan is whether a person perceives social support from important others in his or her life. The current study explored changes in and relationships among perceived social support (SS) and socioemotional adjustment (SEA) across the 1-year transition from elementary to junior high school. Two cohorts of students (N = 140) participated in the current study that took place across a 3-year time span. Analyses of the transition data for boys and girls together reveal declines in perceived total support and teacher support as well as an increase in self-reported school problems. When considering the sexes separately, girls?? perceived total support, close friend support and school support declined while boy??s self-reported school problems increased across the transition. Although social support did not emerge as a mediator or predictor for any of the socioemotional variables in the current study, results reveal that, in general, perceived social support and socioemotional functioning at the end of the last year of elementary school predicts perceived social support and socioemotional functioning at the end of the first year of junior high school. Study limitations and implications for research and practice are discussed.  相似文献   
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The chemical composition of fingermarks could potentially be important for determining investigative leads, placing individuals at the time of a crime, and has applications as biomarkers of disease. Fingermark samples containing triacylglycerols (TAGs) and other components were analyzed using laser desorption/ionization (LDI) time-of-flight mass spectrometry (TOF MS). Only LDI appeared to be useful for this application while conventional matrix-assisted LDI-TOF MS was not. Tandem MS was used to identify/confirm selected TAGs. A limited gender comparison, based on a simple t-distribution and peaks intensities, indicated that two TAGs showed gender specificity at the 95% confidence level and two others at 97.5% confidence. Because gender-related TAGs differences were most often close to the standard deviation of the measurements, the majority of the TAGs showed no gender specificity. Thus, LDI-TOF MS is not a reliable indicator of gender based on fingermark analysis. Cosmetic ingredients present in some samples were identified.  相似文献   
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Suicide by asphyxiation using helium is the most widely-promoted method of "self-deliverance" by right-to-die advocates. However, little is known about persons committing such suicides or the circumstances and manner in which they are completed. Prior reports of suicides by asphyxiation involving helium were reviewed and deaths determined by the North Carolina Office of the Chief Medical Examiner to be helium-associated asphyxial suicides occurring between January 1, 2000 and December 31, 2008 were included in a new case series examined in this article. The 10 asphyxial suicides involving helium identified in North Carolina tended to occur almost exclusively in non-Hispanic, white men who were relatively young (M age = 41.1 T 11.6). In 6 of 10 cases, decedents suffered from significant psychiatric dysfunction; in 3 of these 6 cases, psychiatric disorders were present comorbidly with substance abuse. In none of these cases were decedents suffering from terminal illness. Most persons committing suicide with helium were free of terminal illness but suffered from psychiatric and/or substance use disorders.  相似文献   
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Recent published research has lead to improved techniques for recovering latent fingermarks from metallic surfaces. The present study corroborates and extends some of the work carried out by Bond [1], [2], [3], but an alternative mechanism is proposed for the thermal visualisation of fingermarks based on differential oxidation and the production of interference colours that improve contrast. Fingermarks treated at low temperature could be reheated to enhance recovery, but an upper temperature limit occurs beyond which the mark degrades. The mechanism of enhancement is discussed.  相似文献   
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