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A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.  相似文献   
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Despite its difficulties and inconsistencies in framing those practices andconducts recently unveiled by the press and judicial investigations whichhave caused considerable public discontent, the penal definition ofcorruption still highlights an interesting conceptual diversity across spaceand time that should not be overlooked. Most official discussions about andreferences to corruption and its volume are still framed within these hardparameters. It is, therefore, important to look at the intricacies ofcorruption as a crime in order to understand the virtues and failures ofnational repressive efforts. While crime statistics are of limited use for itsmeasurement, they can nevertheless help to interpret the way corruptionhas been treated through repressive instruments cross-nationally over aperiod of time.The aim of this paper is to assess the dynamics of the various processes ofsetting and revising penal standards to the conduct of office holders and theresults observable from the application of corruption and related offencesacross countries with different legal traditions.  相似文献   
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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   
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测定了痢疾杆菌福氏 2a 30 1株与喹喏酮类药物耐药性相关的 gyrA基因和 parC基因的序列 ,并对其环丙沙星耐药诱变株的 gyrA和 parC基因喹喏酮类药物耐药性决定区 (QRDR)序列进行了测定分析。结果表明 ,痢疾杆菌福氏 2a 30 1株 gyrA和 parC基因分别为 2 6 2 5bp和2 2 5 6bp ,环丙沙星诱导的耐药菌 gyrA基因QRDR(2 4 5bp)发生氨基酸残基 6 9 Ala→Val和 87 Tyr→Asp改变 ,parC基因QRDR(2 37b)发生氨基酸残基 79 Ala→Asp、84 Ala→Glu和 85 Pro→Ala改变。这一研究结果对认识痢疾杆菌喹喏酮类药物耐药性的分子机理具有重要意义  相似文献   
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Studies of restorative justice programs continue to provide a review of restorative justice practice and impact. While this body of research is growing, many questions remain regarding the impact of restorative justice in reducing crime. By relying on individual and community-level data, the present study examined how offense type and poverty level influenced program completion and recidivism among juveniles in a restorative justice program. This study also examined the relationship between program completion and recidivism. Findings revealed that status offenders in the restorative justice program were more likely to complete the program and less likely to recidivate than status offenders in the comparison group. In addition, property offenders in the restorative justice program were less likely to recidivate than property offenders in the comparison group. Poverty level at the community-level had a significant influence in both program completion and recidivism.  相似文献   
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Now that racism has been officially recognized in Brazil, and some universities have adopted affirmative-action admission policies, measures of the magnitude of racial inequality and analyses that identify the factors associated with changes in racial disparities over time assume particular relevance to the conduct of public debate. This study uses census data from 1950 to 2000 to estimate the probability of death in the early years of life, a robust indicator of the standard of living among the white and Afro-Brazilian populations. Associated estimates of the average number of years of life expectancy at birth show that the 6.6-year advantage that the white population enjoyed in the 1950s remained virtually unchanged throughout the second half of the twentieth century, despite the significant improvements that accrued to both racial groups. The application of multivariate techniques to samples selected from the 1960, 1980, and 2000 census enumerations further shows that, controlling for key determinants of child survival, the white mortality advantage persisted and even increased somewhat in 2000. The article discusses evidence of continued racial inequality during an era of deep transformation in social structure, with reference to the challenges of skin color classification in a multiracial society and the evolution of debates about color, class, and discrimination in Brazil.  相似文献   
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