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121.
Brett A. Schweers Jennifer Old P.W. Boonlayangoor Karl A. Reich 《Forensic Science International: Genetics Supplement Series》2008,2(3):243-247
Human blood is the body fluid most commonly encountered at crime scenes, and blood detection may aid investigators in reconstructing what occurred during a crime. In addition, blood detection can help determine which items of evidence should be processed for DNA-STR testing. Unfortunately, many common substances can cause red-brown stains that resemble blood. Furthermore, many current human blood detection methods are presumptive and prone to false positive results. Here, the developmental validation of a new blood identification test, Rapid Stain Identification™-Blood (RSID™-Blood), is described. RSID™-Blood utilizes two anti-glycophorin A (red blood cell membrane specific protein) monoclonal antibodies in a lateral flow strip test format to detect human blood. We present evidence demonstrating that this test is accurate, reproducible, easy to use, and highly specific for human blood. Importantly, RSID™-Blood does not cross-react with ferret, skunk, or primate blood and exhibits no high-dose hook effect. Also, we describe studies on the sensitivity, body fluid specificity, and species specificity of RSID™-Blood. In addition, we show that the test can detect blood from a variety of forensic exhibits prior to processing for DNA-STR analysis. In conclusion, we suggest that RSID™-Blood is effective and useful for the detection of human blood on forensic exhibits, and offers improved blood detection when compared to other currently used methods. 相似文献
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Concern about school violence has been escalating in recent years. A variety of strategies are used in efforts to prevent violence in schools. These remedies can be classified as legal, interactionist, and physical remedies. Legal remedies refer to laws, like the reasonable suspicion to search strategy that allows school officials to search and seize contraband. Interactionist remedies refer to practices that encourage students and other school officials to communicate more openly with school officials about possible cases of violence. Physical remedies refer to strategies that involve altering the school environment in an effort to prevent violence. This study considered the way that 138 school officials from the Commonwealth of Virginia defined the usefulness of these strategies. Attention was also given to whether certain factors contribute to the officials' assessments of the efficacy of each prevention strategy. Results of the study showed that the interactionist, and then legal remedies are believed to be the most useful, while physical remedies are perceived as the least useful strategies. The study uncovered differences of opinion based on racial lines. As an example, more Blacks than Whites were more likely to describe metal detectors as a very useful strategy. Implications of the study are provided. 相似文献
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Over the past decade, directional drilling and hydraulic fracturing enabled an unconventional oil and gas extraction (UOGE) boom in many regions of the United States, including parts of Pennsylvania. This revolution has created serious concerns about the capability of existing institutions to govern important societal outcomes associated with UOGE. We present a conceptual framework for assessing key societal outcomes influenced by UOGE governance. In applying this framework to Pennsylvania, we discern certain institutional strengths that have allowed the Commonwealth to reap appreciable short‐term economic growth from rich resource endowments. We also find, however, that several institutional weaknesses have allowed costs externalized to the environment, public health, and community integrity to offset some proportion of those economic benefits. Likewise, we find that governance of UOGE in Pennsylvania has contributed to a bifurcated sociopolitical landscape wherein adversarial coalitions dispute the legitimacy of the industry and its governance. 相似文献
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The principles that behavior is strongly influenced by the behavior of friends, and that people select each other to be friends on the basis of common characteristics, are based in large part on the many studies of adolescents that found the behavior of friends to be similar. In most of these studies, subjects were asked to describe, the behavior of their friends, and this information was then related to subjects' reports of their own behavior. The research on adolescent smoking and drinking described in this paper departs from that tradition by including friend reports of friend behavior so that results based on the different sources for measuring friend behavior can be compared. Subject report of friend behavior is a stronger correlate, of adolescent behavior than friend report of friend behavior, but the two sources for measuring friend behavior produce the same correlations with subject behavior when using longitudinal designs and controlling for prior subject behavior. The findings are discussed in the context of theoretical and methodological considerations of peer influence and selection.This research was supported by grants from the National Institute on Alcohol Abuse and Alcoholism (AA04099) and the National Institute on Drug Abuse (DA02480) of the U.S. Department of Health and Human Services.Received his Ph.D. from Florida State University. His research interests include adolescent health and evaluation research.Received her M.A. from University of North Carolina at Chapel Hill. Her research interests include methodology and analyses in behavioral sciences and applied social and developmental psychology. 相似文献
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Brian Kelly 《The Journal of peasant studies》2013,40(4):653-687
Important advances in scholarship on the post-emancipation South have made possible a new synthesis that moves beyond broad generalizations about African American agency to identify both the shared elements in black life across the region and the varying capacity of freedpeople to assert their interests in the face of white hostility. Building on a number of recent studies of Reconstruction this article seeks to demonstrate that the varying capacity of freedpeople in South Carolina to shape and defend the new society that would emerge after the end of slavery was rooted in their relative strength at work and in their communities. In Charleston and its lowcountry rural hinterland, demographic strength combined with deeply-rooted traditions of collective assertion to sustain a remarkably vibrant grassroots movement that persisted beyond the overthrow of Reconstruction. From very early on, by contrast, former slaves dispersed across the rural interior found their freedom severely circumscribed by a bellicose and heavily-armed white paramilitary campaign. 相似文献
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