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211.
The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty‐five elements were determined by ICP‐MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K‐means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave‐one‐out cross‐validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples.  相似文献   
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Currently, there is no common understanding of categorizing, conceptualizing, and measuring consumption motives in the performing arts. Study one presents the results of forty-seven semi-structured, in-depth interviews and deepens the understanding of consumption motives. A new framework consisting of cultural and social motives is introduced. This framework is tested in the second study. Here, a quantitative instrument is developed. The results of the principal components analysis refine the framework and demonstrate the following consumption motives: cultural aesthetics (with two dimensions: artistic value and enjoyment of beauty), cultural relaxation, cultural stimulation, social bonding, social attraction, social distinction, and social duty.  相似文献   
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The currency approach assumes black economies to entail larger cash volumes than those needed for transactions in the official economy. Estimates of this hypothesis use e.g. overall cash data. But, for the case of Germany, the growing DM cash amounts in circulation did not only accompany transactions in the national economy, they also disseminated in hoards and in international uses. A series of adjusted cash figures is derived which shows the maximum dimension of national cash uses either for official or black activities. The adjusted cash figures in general grew less fast than overall cash, private consumption, GDP or M1 respectively. They even diminished relative to sales figures which often are accused of being a basis for black activities. This enhances the presumption that, contrary to some contentions in the literature, black activities during the times of the DM-regime played a minor or even decreasing role in Germany.  相似文献   
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Increasing politicization in EU member states about European issues can be expected to strengthen the impact of attitudes towards Europe on vote choice in European Parliament (EP) elections. At the same time this impact is likely to vary between voters and contexts as a function of political information. This study explores the role of political information in explaining individual and contextual heterogeneity in the degree of EU issue voting. Using a two-step hierarchical estimation procedure to explore both individual and contextual variation, we show that while EU issue voting in the 2009 EP elections is only slightly more pronounced among the politically sophisticated, it is clearly more extensive in contexts that provide higher levels of political information on European matters.  相似文献   
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Forensic laboratories do not have the infrastructure to process or store contaminated DNA samples that have been recovered from a crime scene contaminated with chemical or biological warfare agents. Previous research has shown that DNA profiles can be recovered from blood exposed to several chemical warfare agents after the agent has been removed. The fate of four toxic agents, sulfur mustard, sodium 2-fluoroacetate, sarin, and diazinon, in a lysis buffer used in Promega DNA IQ extraction protocol was studied to determine if extraction would render the samples safe. Two independent analytical methods were used per agent, selected from GC-MS, 1H NMR, 19F NMR, (31)P NMR, or LC-ES MS. The methods were validated before use. Determinations were carried out in a semi-quantitative way, by direct comparison to standards. Agent levels in the elution buffer were found to be below the detectable limits for mustard, sarin, sodium 2-fluoroacetate or low (<0.02 mg/mL) for diazinon. Therefore, once extracted these DNA samples could be safely processed in a forensic laboratory.  相似文献   
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