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61.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated. 相似文献
62.
David P. Farrington 《Journal of Experimental Criminology》2006,2(2):121-141
Following the tradition of Joan McCord's work, this paper reviews longitudinal-experimental studies in criminology with community samples of at least 100 persons, follow-up periods of at least 5 years, personal interviews, and measures of offending. The main advantages of such studies are in investigating both the natural history of development (including the effects of risk/protective factors and life events) and the impact of interventions on offending. This paper also reviews advantages and problems of prospective longitudinal surveys, randomized experiments, and longitudinal-experimental studies in criminology. Four key longitudinal-experimental studies were conducted by Joan McCord, Richard Tremblay, Lawrence Schweinhart and David Olds. Other studies have been conducted, or are currently under way, but no criminological study has yet been published with several years of personal data on participants both before and after an intervention.Joan McCord Award Lecture given at the American Society of Criminology, Toronto, Canada. 相似文献
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The link between resource deprivation and urban violence has long been explored in criminological research. Studies, however, have largely ignored the potential for resource deprivation in particular communities to affect rates of violence in others. The relative inattention is notable because of the strong theoretical grounds to anticipate influences that extend both to geographically contiguous areas and to those that, though not contiguous, share similar social characteristics. We argue that such influences—what we term spatial and social proximity effects, respectively—constitute a central feature of community dynamics. To support this argument, we develop and test theoretically derived hypotheses about spatial and social proximity effects of resource deprivation on aggregated and disaggregated homicide counts. Our analyses indicate that local area resource deprivation contributes to violence in socially proximate communities, an effect that, in the case of instrumental homicides, is stronger when such communities are spatially proximate. We conclude by discussing the implications of our findings for theories focused on community‐level social processes and violence, and for policies aimed at reducing crime in disadvantaged areas. 相似文献
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Netherlands International Law Review - 相似文献
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Eight homicidal youths were assessed for language disorders and psychiatric diagnoses using a battery of standardized language tests and the Diagnostic Interview for Children and Adolescents. Both language disorders and Diagnostic and Statistical Manual III-R psychiatric diagnoses were present in all subjects. 相似文献
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Routine crime in exceptional times: The impact of the 2002 Winter Olympics on citizen demand for police services 总被引:2,自引:0,他引:2
Despite their rich theoretical and practical importance, criminologists have paid scant attention to the patterns of crime and the responses to crime during exceptional events. Throughout the world large-scale political, social, economic, cultural, and sporting events have become commonplace. Natural disasters such as blackouts, hurricanes, tornadoes, and tsunamis present similar opportunities. Such events often tax the capacities of jurisdictions to provide safety and security in response to the exceptional event, as well as to meet the “routine” public safety needs. This article examines “routine” crime as measured by calls for police service, official crime reports, and police arrests in Salt Lake City before, during, and after the 2002 Olympic Games. The analyses suggest that while a rather benign demographic among attendees and the presence of large numbers of social control agents might have been expected to decrease calls for police service for minor crime, it actually increased in Salt Lake during this period. The implications of these findings are considered for theories of routine activities, as well as systems capacity. 相似文献