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181.
Using Cluster Analysis and ICP‐MS to Identify Groups of Ecstasy Tablets in Sao Paulo State,Brazil
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Camila Maione M.Sc. Vanessa Cristina de Oliveira Souza M.Sc. Loraine Rezende Togni M.Sc. José Luiz da Costa Ph.D. Andres Dobal Campiglia Ph.D. Fernando Barbosa Ph.D. Jr. Rommel Melgaço Barbosa Ph.D. 《Journal of forensic sciences》2017,62(6):1479-1486
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
182.
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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184.
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
185.
Yves Poullet 《Computer Law & Security Report》2011,27(1):6-20
The present paper1 aims both at introducing the legal aspects of the protection of minors in cyberspace and analysing and criticizing certain main features embedded in this legal approach of young people protection. After a short introduction underlining the concept of child’s rights and the reason why this right has been particularly proclaimed in the context of the cyberspace, the first section describes the new technological features of the ICT environment and linked to this evolution the increasing risks the minors are confronted with. A typology of cyber abuses is proposed on the basis of these considerations. A list of EU or Council of Europe texts directly or indirectly related to the minors’ protection into the cyberspace is provided. The second section intends to analyse certain characteristics of the legal approach as regards the ways by which that protection is conceived and effectively ensured. Different principles and methods might be considered as keywords summarizing the legal approach and to a certain extent, fixing a partition of responsibilities taking fully into account the diversity of actors might be deduced from the different regulatory documents.The third section comes back to the different complementary means by which the Law is envisaging the minors’ protection. The obligation to create awareness about the potential risks minors might incur definitively is the first one. The omnipresent reference in all the legal texts to the role of self-regulatory interventions constitutes another pillar of the protection envisaged by the Law. After having described the multiple instruments developed in the context of this self-regulation (labels, codes of conduct, hotlines, ODR…) or even co-regulation, the paper examines the conditions set by the European legislators as regards these instruments. Technology might be considered as a fourth method for protecting children. Our concern will be to see how the Law is addressing new requirements as regards the technological solutions and their implementation. The present debates about the liability of the actors involved in applications or services targeted or not vis-à-vis the minors like SNS or VSP operators are evoked. As a final point the question of the increasing competences of LEA and the reinforcement of the criminal provisions in order to fight cyber abuses against minors will be debated. In conclusion, we will address final recommendations about the way by which it would be possible to reconcile effective minors’ protection and liberties into the cyberspace. 相似文献
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187.
Catherine E. de Vries Wouter van der Brug Marcel H. van Egmond Cees van der Eijk 《Electoral Studies》2011,30(1):16-28
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
188.
189.
Wilkinson DA Hulst AG de Reuver LP van Krimpen SH van Baar BM 《Journal of forensic sciences》2007,52(6):1272-1283
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
190.
Esseiva P Ioset S Anglada F Gasté L Ribaux O Margot P Gallusser A Biedermann A Specht Y Ottinger E 《Forensic science international》2007,167(2-3):247-254
Organised criminality is a great concern for national/international security. The demonstration of complex crimes is increasingly dependant on knowledge distributed within law-enforcement agencies and scientific disciplines. This separation of knowledge creates difficulties in reconstructing and prosecuting such crimes. Basic interdisciplinary research in drug intelligence combined with crime analysis, forensic intelligence, and traditional law enforcement investigation is leading to important advances in crime investigation support. Laboratory results constitute one highly dependable source of information that is both reliable and testable. Their operational use can support investigation and even provide undetected connections or organisation of structure. The foremost difficulties encountered by drug analysts are not principally of a chemical or analytical nature, but methodologies to extract parameters or features that are deemed to be crucial for handling and contextualising drug profiling data. An organised memory has been developed in order to provide accurate, timely, useful and meaningful information for linking spatially and temporally distinct events on a national and international level (including cross-border phenomena). Literature has already pointed out that forensic case data are amenable for use in an intelligence perspective if data and knowledge of specialised actors are appropriately organised, shared and processed. As a particular form of forensic case data, the authors' research focuses on parameters obtained through the systematic physical and chemical profiling of samples of illicit drugs. The procedure is used to infer and characterise links between samples that originate from the same and different seizures. The discussion will not, however, focus on how samples are actually analysed and compared as substantial literature on this topic already exists. Rather, attention is primarily drawn to an active and close collaboration between magistrates, forensic scientists, law enforcement investigators and crime analysts from different institutions with the aim of generating, using and validating relevant profiling case data as integral part of investigative and crime analysis processes. Original advances are highlighted through experiences from criminal investigations of offences related to the unlawful importation, exportation, supply and possession of illicit drugs. 相似文献