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261.
In recent years, the growth in knowledge of the characteristics and activities of gang members has been impressive. Little is known, however, about the key features of younger gang members, those in middle school. Ninety-six middle school students who self-reported current or former gang membership in a school-based survey form the sample for this analysis. This study examined four dimensions of gang membership: joining the gang, processes involved in gang life, organizational characteristics of the gang, and family characteristics. Gang membership appears to be transient, with a weak hold on members during periods of membership. This is especially true when the results of this study are compared to studies that used older members. 相似文献
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Policy Sciences - Regulation of rapidly developing changing policy areas is a well-known challenge for any government. It can involve balancing factors from elite factional politics to development... 相似文献
264.
Chadwick S Maynard P Kirkbride P Lennard C Spindler X Roux C 《Journal of forensic sciences》2011,56(6):1505-1513
In current casework, most post-cyanoacrylate stains rely on luminescence emission in the visible region (400-700 nm). While traditional stains such as rhodamine 6G work well under most circumstances, some surfaces may generate background luminescence under the same conditions. Detection in the near-infrared region (NIR > 700 nm) has shown to be effective in minimizing the interferences from such surfaces. The laser dye styryl 11 generated strongly luminescent fingermarks when applied after cyanoacrylate fuming on all surfaces tested. When compared to rhodamine 6G, the dye was superior only when viewed in the NIR. Styryl 11 was subsequently combined with rhodamine 6G, and the mixed stain formulation (named StaR 11 by the authors) induced stronger luminescence compared with styryl 11 alone with an ability to visualize in both the visible and NIR regions. Reliable and consistent results were obtained when using either styryl 11 alone or the STaR 11 mixture. The enhancement achieved did not otherwise vary depending on the source of the fingermark secretions. With visualization possible in both the visible and NIR regions, the styryl 11/rhodamine 6G mixture showed significant potential as a post-cyanoacrylate stain. 相似文献
265.
Crosson S 《Politics and the life sciences》2011,30(2):31-42
Research in recent decades has shown that although conventional fisheries management strategies such as fishing seasons, size limits, or gear restrictions can provide sufficient biological protection to fisheries stocks, they do not necessarily lead to satisfactory social or economic outcomes. In their stead, the merits and shortcomings of a variety of alternate management systems, including individual transferable quotas, have been proposed, implemented, and analyzed. Few investigations, however, have examined actual fishers' preferences for different management systems. Integrating results from a mail survey of North Carolina commercial fishers with their individual harvest histories and sociodemographic profiles shows that economic and cultural variables both play a significant role in management system preference. The analysis introduces the use of the Herfindahl-Hirschman Index (HHI), a measure of investment diversity, as a measure of diversity in fisheries harvests and demonstrates an association with management preferences. Social and family factors are also notable indicators. 相似文献
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Jeffrey L. Furman Fiona Murray Scott Stern 《Journal of policy analysis and management》2012,31(3):661-705
This paper articulates a citation‐based approach to science policy evaluation and employs that approach to investigate the impact of the United States’ 2001 policy regarding the federal funding of human embryonic stem cell (hESC) research. We evaluate the impact of the policy on the level of U.S. hESC research, the U.S. position at the knowledge frontier, and the strategic response of U.S. scientists. Consistent with recent research on the science of science and innovation policy, we employ a difference‐in‐differences approach using bibliometric data with the aim of analyzing the causal impact of the policy on cumulative research. Our estimates suggest that in the aftermath of the 2001 policy, U.S. production of hESC research lagged 35 to 40 percent behind anticipated levels. However, this relative decline was largely concentrated in the years 2001 to 2003 and ameliorated over time. The rebound in U.S. hESC research after 2003 was driven by contributions by researchers at elite U.S. institutions and U.S. researchers who collaborated with international partners. The results suggest that scientists respond strategically to research funding restrictions and that modest science policy shifts can have a significant influence on the within‐country composition of research and the pattern of global research collaboration. 相似文献
268.
This article examines the origins and main strands of recent debates within the international development community regarding the tensions between increasing aid allocation to so-called ??fragile states?? and growing domestic and international pressure for donors to demonstrate measurable results and returns on their investments. With particular reference to the UK context, the paper examines how the confluence of these two agendas is being viewed, at least publicly, and some of the main arguments that have been put forward about why they may be difficult to pursue simultaneously. It asks whether or not it is feasible that donors will explicitly seek to address and resolve the apparent trade-offs between these two agendas, and concludes that in both international and domestic political arenas, ??good enough?? aid effectiveness, or a more nuanced, ??developmentised?? understanding of value for money, are unlikely to become palatable or politically viable any time soon. 相似文献
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