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671.
This study evaluated the efficacy of a school-based anxiety prevention program among urban children exposed to community violence. Students who attended Title 1 public elementary schools were screened. Ninety-eight 3rd-5th-grade students (ages 8-12; 48% female; 92% African American) were randomized into preventive intervention versus wait list comparison groups. Students attended 13 biweekly one-hour group sessions of a modified version of FRIENDS, a cognitive-behavioral anxiety intervention program. Results indicated that both intervention and control groups manifested significant reductions in anxiety symptomatology and total exposure to community violence, along with improved standardized reading achievement scores. Additional gains observed only in the intervention group were increased standardized mathematics achievement scores, decreased life stressors, and reduced victimization by community violence. The intervention was equally efficacious for both genders and for children exposed to higher, compared to lower, levels of community violence. Implications for comprehensive, culturally and contextually relevant prevention programs and research are discussed.  相似文献   
672.
Abstract: Low concentrations of microbial pathogens in pure and mixed samples were detected using a bead‐based, liquid array technology. A 20‐bp sequence in the 23S rRNA gene, rrl, was amplified in four microorganisms: Bacillus cereus, Escherichia coli, Salmonella enterica and Staphylococcus aureus. PCR products were positively identified with the Luminex® 100? system. The system could detect very low amounts of DNA and the instrument response was proportional to the input concentration. The lower limit of detection (LLD) was determined to be 0.5 ng for B. cereus and E. coli and 2 ng for S. enterica. The LLD for S. aureus was not determined as the instrument response was still above the threshold when quantities of DNA as low as 0.25 ng were used. The platform positively identified organisms present in mixed samples even when the minor component was overshadowed by a 10‐fold excess of the major component.  相似文献   
673.
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   
674.
The protests of December 2001 in Argentina were the most visible manifestation of a larger cycle of contention, which continues to have a substantial influence on the forms, tactics and goals of social movements throughout the country. This paper provides a critical overview of these lasting effects. In particular, we focus on three areas where the consequences of the crisis for collective action have been particularly strong: performative politics, coalition-building, and institutional support for grassroots networks. We conclude by reflecting on the implications for participatory democracy and the consolidation of a highly engaged civil society.  相似文献   
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