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171.
Samantha C. de Freitas Marco A.Z. dos Santos Lucas M. Berneira Rafael S. Ortiz Claudio M.P. de Pereira 《Science & justice》2019,59(2):190-198
Over the past decades, consume of slimming agents considerably increased in several countries, including Brazil, due to weight-loss and stimulant properties. Since these drugs are controlled to prevent illicit and indiscriminate use, there is a parallel illegal market that uses the Internet and irregular pharmacies in order to distribute these formulations. Slimming agents produced by these illegal sources are known for being manufactured with little or none quality control resulting in uncertain and unknown formulations. For forensic purposes, apprehended pharmaceuticals have to undergo a process of chemical identification that can be difficult due to its complex matrix. In this sense, application of assisted energies in the extraction step such as microwave irradiation can be a promising method to increase the recuperation of the target molecules of the sample. Therefore, the aim of this research was to identify four slimming agents apprehended in Brazil by means of visual inspection, Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry and Gas Chromatography – Mass Spectrometry. Moreover, the efficiency of solid-liquid extraction and microwave-assisted extraction was compared. It should be noted that our work was one of the few to use Differential Scanning Calorimetry and the application of microwave irradiation in the analysis of apprehended materials. Results showed that the majority of the samples was counterfeit being composed of one or several adulterants or contaminants. Initially, visual inspection resourcefully screened the slimming agents for possible signs of falsification, however it failed to detect fraudulent products that were very similar to veridical medicines. Sequentially, Fourier Transform Infrared Spectroscopy detected functional groups present in the samples while the presence or absence of the alleged active ingredients were successfully measured with Differential Scanning Calorimetry and, thus, providing a full chemical screening of the apprehended materials. Gas Chromatography- Mass Spectrometry confirmed the presence of adulterants such as caffeine, fluoxetine and phenolphthalein as well as contaminants such as sulfurol in the falsified samples. Finally, comparison of extraction procedures indicated that microwave-assisted extraction increased the recovery of compounds detected in chromatographic analysis to a greater extent than solid-liquid extraction. 相似文献
172.
Vander Freitas Melo Samara Alves Testoni Lorna Dawson Alexandre Guilherme de Lara Fábio Augusto da Silva Salvador 《Science & justice》2019,59(6):667-677
Soil forensics utilizes extensive soil information to answer legal questions and test hypotheses. The main difficulty often is the determination of different variables from a small amount of soil sample collected on the suspect. We developed a sequential mineralogical and chemical analyses to assess a limited quantity of soil vestiges (0.5 g) from a suspect's vehicle (adhered to the outside rear-view mirror and to the left front fender) involved in a murder case and compared them with the surface samples found at the victim's body disposal site at the Graciosa Road, Paraná State, Brazil. All results affirm that the suspect’s vehicle could have been in contact with the edge of the Graciosa Road, approximately the place where the victim’s body was located. As a result of the soil analysis and comparison, the results support the likely contact of the suspect’s vehicle with the crime scene. 相似文献
173.
An Aquatic Decomposition Scoring Method to Potentially Predict the Postmortem Submersion Interval of Bodies Recovered from the North Sea 下载免费PDF全文
Marjolijn A. van Daalen M.D. Dorothée S. de Kat M.D. Bernice F.L. Oude Grotebevelsborg M.D. Roosje de Leeuwe M.Sc. Jeroen Warnaar M.Sc. Roelof Jan Oostra Ph.D. Wilma L.J. M Duijst‐Heesters Ph.D. 《Journal of forensic sciences》2017,62(2):369-373
This study aimed to develop an aquatic decomposition scoring (ADS) method and investigated the predictive value of this method in estimating the postmortem submersion interval (PMSI) of bodies recovered from the North Sea. This method, consisting of an ADS item list and a pictorial reference atlas, showed a high interobserver agreement (Krippendorff's alpha ≥ 0.93) and hence proved to be valid. This scoring method was applied to data, collected from closed cases—cases in which the postmortal submersion interval (PMSI) was known—concerning bodies recovered from the North Sea from 1990 to 2013. Thirty‐eight cases met the inclusion criteria and were scored by quantifying the observed total aquatic decomposition score (TADS). Statistical analysis demonstrated that TADS accurately predicts the PMSI (p < 0.001), confirming that the decomposition process in the North Sea is strongly correlated to time. 相似文献
174.
Using Cluster Analysis and ICP‐MS to Identify Groups of Ecstasy Tablets in Sao Paulo State,Brazil 下载免费PDF全文
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
175.
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
176.
177.
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
178.
179.
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
180.