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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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Drug trade is widely seen as a phenomenon rather new to the Netherlands. However, at the beginning of the 20th century the Dutch pharmaceutical industries were already extensively involved in the production of both opiates and cocaine, and they went on exporting large quantities of these drugs after the Opium Act (1919) took force. Until the 1960s, arrests were not at all common, and these largely affected minority groups like Chinese opium smokers and black marijuana users. Since then, drug control efforts have increased by leaps and bounds. At first, cannabis was the main target; then the focus turned to heroin, and that was later joined by cocaine. This paper traces the history of the drug trade and drug control in the Netherlands, with emphasis on their development in Amsterdam. The conclusion is reached that, in spite of drastic changes in both drug trade and drug control, certain ideologies, constructs and strategies have remained remarkably stable.  相似文献   
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Goran Therborn, European Modernity and Beyond: The Trajectory of European Societies, (Sage, London 1995). 403pp. ISBN 8039 8934 2.

John McGany and Brendan O'Leary, Explaining Northern Ireland, (Blackwell, Oxford 1995). 535pp. ISBN 0–631–18349–3.  相似文献   

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Abstract: Despite the enormous share of social services in government spending and the strong incentives on government to rationalize services, the alternative service delivery (asd) literature has given little attention to social–service delivery. In our paper, we review current approaches taken to social–service delivery in Ontario by the Ministry of Community and Social Services (mcss). Although the mcss retains responsibility for the social–services system, it provides social services almost exclusively through private non–profit agencies under purchase of service contracts. Two themes emerge from our examination of these relationships. First, the standard privatization model has limited application to social–services delivery. Contracts are generally not awarded in a competitive fashion, and contract termination discipline is rarely applied. Given the inadequacies of current performance measures for social services, monitoring contract performance is difficult. Second, the success of attempts to shift provision to private non–governmental entities is intimately linked to the effectiveness of accountability mechanisms, especially outcome–based performance measures. Improving performance measurement is therefore an important priority. In addition to advocating further research into the effectiveness of social services, one interesting mcss initiative has been to look to client communities to help monitor the performance of agencies. We conclude that among the different institutional approaches to social–service delivery, contracting with non–profits is the one that currently seem most appropriate. Sommaire: Malgré la part énorme des dépenses gouvernementales consacrée aux services sociaux et malgré les efforts gouvemementaux pour rationaliser les services, les ouvrages publiés sur la prestation de services par des moyens de rechange n'ont consacré que peu d'attention à la prestation des services sociaux. Nous examinons dam cet article les méthodes adoptées pour la prestation des services sociaux en Ontario par le ministére des Services sociaux et communautaires (mssc). Même s'il retient la responsabilité du réseau des services sociaux, le mssc foumit les services sociaux presque exclusivement par I'intermédiaire d'organismes privés à but non lucratif, en vertu de contrats d'achat de services. En examinant ces rapports, nous en dégageons deux thémes. Premiérement, le modéle de privatisation standard ne s'applique que de maniére limitée à la prestation des services sociaux. Les contrats ne sont généralement pas accordés de maniére concurrentielle, et on n'utilise que rarement la résiliation de contrats en tant que mesure disciplinaire. II est difficile de surveiller la qualité d'exécution des contrats, vu l'insuffisance des mesures de rende–ment actuelles concernant les services sociaux. Deuxièmement, le transfert de I'exé–cution aux organismes privés non gouvernementaux ne peut réussir qu'en présence de mécanismes de responsabilisation adéquats, et en particulier de moyens permet–tant de mesurer le rendement en fonction des résultats obtenus. I1 importe donc d'améliorer les moyens de mesure du rendement. Selon le mssc, en plus des recher–ches suppéementaires concernant l'efficacite des services sociaux, il faut faire appel aux groupes de clients pour aider À surveiller le rendement des organismes. En conclusion, parmi les diverses méthodes institutionnelles de prestation des services sociaux, la sous–traitance faisant appel aux secteurs à but non lucratif semble çtre aujourd'hui la plus appropriwaee. [I]t is no exaggeration to say the state and local governments tend not to know what results their social service contracts are buying. Because competition is low, they have little opportunity to test the market to see what alternatives they have. Few resources are spent to look past what contractors themselves report. The political system has few incentives to dig deeper and many more incentives to maintain the status quo— The problems with oversight underline earlier observations: whatever advantages contracting–out for social services might produce, greater efficiency through market–tested competition is not one of them. State and local governments are engaging in the equivalent of a shopping trip while blindfolded, with little effort spent to squeeze the tomatoes or thump the watermelons  相似文献   
20.
I present a model of the interaction between a government, a terrorist organization, and potential terrorist volunteers in which, as a result of an endogenous choice, individuals with low ability or little education are most likely to volunteer to join the terrorist organization. However, the terrorist organization screens the volunteers for quality. Consequently, the model is consistent with two seemingly contradictory empirical findings. Actual terrorist operatives are not poor or lacking in education. And yet lack of economic opportunity and recessionary economies are positively correlated with terrorism. The model also endogenizes the effect of government counterterrorism on mobilization. Government crackdowns have competing effects on mobilization: they decrease the ability of terrorists to carry out effective attacks (making mobilization less attractive), and they foment ideological opposition to the government and impose negative economic externalities (making mobilization more attractive). This provides conditions under which government crackdowns increase or decrease mobilization.  相似文献   
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