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Serious Youth Gun Offenders and the Epidemic of Youth Violence in Boston   总被引:1,自引:0,他引:1  
Boston, like many other major cities, experienced a sudden increase in youth homicides during the late 1980s and early 1990s. Research evidence suggests that the recent epidemic of urban youth violence was intensely concentrated among criminally active young black males residing in disadvantaged urban neighborhoods rather than all young black males residing in disadvantaged black neighborhoods. Other researchers, however, suggest that there was a diffusion of guns and gun violence from youth involved in street crack markets to youth outside the drug trade who armed themselves primarily for self-protection against the armed criminally active youth. In this paper, criminal history data are analyzed to determine whether the criminal profile of Boston arrested youth gun offenders changed over time and micro-level data on youth gun assault incidents in Boston are examined to unravel whether there were noteworthy changes in the nature of these violent events over time. The results of these analyses suggest that the youth violence epidemic in Boston was highly concentrated among serious youth gun offenders rather than a diffusion of guns away from the street drug trade, gangs, and criminally active youth.  相似文献   
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The requirements for dependable management of complex hazardous technologies include multiple barriers against serious failure, clear accountability for errors, and credibility for the decision-making process. Unfortunately, these requirements are in direct conflict. These conflicts can undermine the public's assurance that their health and safety concerns are being properly addressed. These conflicts can be reduced by the adoption of policies that enhance information exchange and evaluation, thereby, complementing the current policies based on physical safe guards and adversarial processes.  相似文献   
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The detection of group-specific component (Gc) from serum and bloodstains has been widely used in the forensic laboratory. A recent increase in substituted or adulterated urine samples in various drug screening programs has necessitated methods to determine the donor. This paper discusses the detection of Gc from urine samples. The samples were concentrated and applied to ultrathin polyacrylamide gel and focused for 150 min. This method separates the samples into the three common phenotypes found in all human populations. A nitrocellulose membrane blotting technique was used to detect the Gc bands. Serum and urine samples were collected from each individual and were typed for Gc. Urine samples tested after 6 months of storage (4 degrees C) were still readable. This method provides the forensic laboratory with an additional test from a body fluid which, until recently, provided little information.  相似文献   
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