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This research expands past investigations into the influence of low self-control as a risk factor for criminal victimization. Specifically, we consider two questions: (1) whether low self-control at one point in time can predict future victimization, and (2) whether victims alter lifestyle choices (like their own delinquency and contact with delinquent peers) in response to their earlier victimization. We answered these questions using three waves of adolescent panel data from the evaluation of the Gang Resistance Education and Training program. Our results support the predictions of self-control theory, showing that low self-control measured at an earlier time is associated with later victimization, even after controlling for past victimization, delinquency, social bonds, and delinquent peer contact. Likewise, self-control appears to influence the relationship between earlier victimization and later lifestyles.
Christopher J. SchreckEmail:
  相似文献   
134.
Laser-induced detection of fluorescent labeled PCR products and multi-wavelength detection (i.e., multicolor analysis) enables rapid generation of mtDNA sequencing profiles. Traditionally, polyacrylamide slab gels have been used as the electrophoretic medium for mtDNA sequencing in forensic analyses. Replacement of slab gel electrophoresis with capillary electrophoresis (CE) can facilitate automation of the analytical process. Automation and high throughput can be further enhanced by using multicapillary electrophoretic systems. The use of the ABI Prism 3100 Genetic Analyzer (ABI 3100, Applied Biosystems, Foster City, CA) as well as the ABI Prism 310 Genetic Analyzer (ABI 310, Applied Biosystems, Foster City, CA) were evaluated for mtDNA sequencing capabilities and compared with sequencing results obtained on the platform currently in use in the FBI Laboratory (the ABI Prism 377 DNA Sequencer, ABI 377, Applied Biosystems, Foster City, CA). Various studies were performed to assess the utility of the ABI 3100, as well as the ABI 310 for mtDNA sequencing. The tests included: comparisons of results obtained among the ABI 3100, the ABI 310 and the ABI 377 instruments; comparisons of results obtained within and between capillary arrays; evaluation of capillary length; evaluation of sample injection time; evaluation of the resolution of mixtures/heteroplasmic samples; and evaluation of the sensitivity of detection of a minor component with reduced template on the ABI 3100. In addition, other studies were performed to improve sample preparation; these included: comparison of template suppression reagent (TSR, Applied Biosystems, Foster City, CA) versus formamide; the use of Performa DTR Gel Filtration Cartridges (Edge BioSystems Inc., Gaithersburg, MD) versus Centri-Sep Spin Columns (Princeton Separations, Adelphia, NJ) for product purification after cycle sequencing; and sample stability after denaturation. The data support that valid and reliable results can be obtained using either capillary electrophoresis instrument, and the quality of sequencing results are comparable to or better than those obtained from the ABI 377 instrument.  相似文献   
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The application of supercritical fluid chromatography (SFC) in forensic science is reviewed. The applications centre on the analysis of explosives and of drugs of abuse. The systems employed are discussed in the context of comparison with gas chromatography and high-performance liquid chromatography methods which are traditionally used for such analyses. The advantages and disadvantages of SFC over these methods are discussed. Recommendations are made for the developments which are required in SFC technology if it is to find greater application in forensic science.  相似文献   
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Economic Change and Restructuring - Two recent studies of SME share determination have employed a partial adjustment model which specifies disequilibrium as the sole means of explanation....  相似文献   
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The possibility that homicides can spread from one geographic area toanother has been entertained for some time by social scientists, yetsystematic efforts to demonstrate the existence, or estimate the strength,of such a diffusion process are just beginning. This paper uses exploratoryspatial data analysis (ESDA) to examine the distribution of homicides in 78counties in, or around, the St. Louis metropolitan area for two timeperiods: a period of relatively stable homicide (1984–1988) and aperiod of generally increasing homicide (1988–1993). The findingsreveal that homicides are distributed nonrandomly, suggestive of positivespatial autocorrelation. Moreover, changes over time in the distribution ofhomicides suggest the possible diffusion of lethal violence out of onecounty containing a medium-sized city (Macon County) into two nearbycounties (Morgan and Sangamon Counties) located to the west. Althoughtraditional correlates of homicide do not account for its nonrandom spatialdistribution across counties, we find some evidence that more affluentareas, or those more rural or agricultural areas, serve as barriers againstthe diffusion of homicides. The patterns of spatial distribution revealedthrough ESDA provide an empirical foundation for the specification ofmultivariate models which can provide formal tests for diffusion processes.  相似文献   
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The implications of different potential affirmative action policies depend on three factors: selection rate from the applicant pool, base rate of qualified applicants, and accuracy of performance predictions. A series of analyses was conducted under various assumptions concerning affirmative action plans, causes of racial differences in average college admissions test scores, and racial differences in accuracy of performance predictions. Evidence suggesting a lower level of predictive accuracy for African Americans implies that, under a program of affirmative action, both proportionately more false positives (matriculated students who do not succeed) and proportionately more false negatives (rejected applicants who could have succeeded) will be found among African American applicants. Unless equivalent levels of predictive accuracy are achieved for both groups, no admission policy can be fair simultaneously to majority group applicants and African American applicants. © 2002 by the Association for Public Policy Analysis and Management.  相似文献   
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Stewart  Ian 《Publius》1990,20(1):99-112
The boundary that separates the Canadian provinces of New Brunswickand Nova Scotia was established in 1784. This article contraststhe political orientations of those who live within a commonborder region, but on opposite sides of the New Brunswick andNova Scotia boundary, and concludes that the boundary line hasindependently had a divisive impact on the area's politicalculture. Unless this particular provincial boundary is atypical,therefore, the institution of federalism is, in some measure,inherently centrifugal.  相似文献   
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