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The 1H nuclear magnetic resonance (NMR) chemical shifts and coupling constants of heroin's D ring H-15 alpha, H-15 beta, and H-16 alpha, and H-16 beta are presented. These assignments were accessible through the introduction of a double bond (delta 15,16) in heroin. The resulting compound, delta 15,16 didehydroheroin, was subjected to deuterium exchange or stereoselective reduction or both. Reduced products d1-16 alpha heroin d2-15 alpha, 15 beta-heroin, and d3-15 alpha, 15 beta, 16 alpha-heroin are presented. Heroin with deuterated acetyls is also presented for 1H NMR spectral clarity in the D ring area.  相似文献   
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The costs of occupational licensing fall disproportionately on minorities and the poor. Licensing seeks to eliminate the lower-quality, lower-price services that low-income consumers would be more likely to select. Perhaps more important, however, is the impact on workers who are denied entry into the occupation. Recent evidence confirms that licensing regulations esclude less-educated and minority workers more than proportionally. The consequences for these excluded workers include unemployment or lower earnings—either by moving to a less-favored occupation or practicing without a license. The outcomes ofnonprofessional trades regulated by licensing are similar to those predicted by segmented labor market theory. Those who fail to obtain the credential (license) are denied access to the trade even if they are no less productive.  相似文献   
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This article examines a major assumption of street supervisors in police agencies—that control of police officer behavior is dependent on strict hierarchical organization. The intellectual roots of this assumption are examined, and an emerging perspective developed from direct observation of patrol operations is presented. The research questions are addresses with data that were collected from observations of patrol activities in 60 residential neighborhoods in 24 agencies. The analysis, which is referenced to officers' shifts of duty, shows that the effect of supervision is in the direction posited by the authors of traditional police administration texts, but the magnitude of the effect is not overly strong. The findings are used to inform the evaluation of a common policy option directed at improving officer performance through supervision.  相似文献   
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This article traces the emergence of federal citizen involvement policy during the past 34 years which is described as emerging in an incremental and disjointed manner since World War II. The essay summarizes the major stages in this evolution, describes important principles associated with each stage, and identifies 24 elements that constitute an accrued federal citizen involvement policy.  相似文献   
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