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151.
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   
152.
Washington University v. Catalona revolves around ownership of tissue samples provided by patients for research purposes, raising significant ethical and legal questions concerning patient rights, current human research practices, and the treatment of samples as capital resources by the research institution.  相似文献   
153.
In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported.  相似文献   
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In a case of suicidal application of electricity differences between the rectal temperature of the body and the suspected time of death were observed.In order to answer the question whether an electric current from hand to hand over >30 min led to a rise in body temperature FEM-based computer simulations and animal experiments were carried out. Both resulted in a warming of the soft parts in the arm without warming the body core. Thus a temperature-based estimation of the time since death can also be used in cases with electricity as the cause of death. Besides, in the animal experiment we found a spontaneous rise in the body core temperature even without application of electricity which may be a reason for the typical temperature plateau after death.  相似文献   
156.
This article examines the question of trust in Bosnia and Herzegovina with a special focus on the role of ethnicity. We find generalised trust to be low and declining in Bosnia and Herzegovina. Moreover, generalised trust is negatively affected by the degree of ethnic heterogeneity in the region. However, a further examination of trust reveals a more complex relationship between ethnicity and trust: people tend to show low levels of trust in all other people irrespective of their ethnic belongings. We argue that ethnic distribution might capture some other regional specific characteristics that also affect the level of trust.  相似文献   
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Fair Trade has become a dynamic and successful dimension of an emerging counter-tendency to the neo-liberal globalisation regime. This study explores some of the dilemmas facing the Fair Trade movement as it seeks to broaden and deepen its impact among the rural poor of Latin America's coffee sector. We argue that the efforts to broaden Fair Trade's economic impact among poor, small-scale producers are creating challenges for deepening the political impact of a movement that is based on social justice and environmental sustainability. The study is based on two years' research and seven case studies of Mexican and Central American small-scale farmer cooperatives producing coffee for the Fair Trade market.  相似文献   
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