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Andrzej Kwiatkowski M.Eng. Małgorzata Czerwicka Ph.D. Janusz Smulko Ph.D. Piotr Stepnowski Ph.D. 《Journal of forensic sciences》2014,59(5):1358-1363
Illegal alcoholic beverages are often introduced into market using cheap technical alcohol, which is contaminated by denatonium benzoate (Bitrex) of very small concentration. Bitrex is the most bitter chemical compound and has to be removed before alcohol consumption. The home‐made methods utilize sodium hypochlorite to disintegrate particles of denatonium benzoate in alcohol and to remove bitter taste before trading. In this experimental studies, we propose a novel method that detects in a fast way the remnants of denatonium benzoate in dubious alcohol samples by Raman spectroscopy. This method applies a portable Raman spectrometer of excitation wavelength 785 nm and utilizes the effect of surface‐enhanced Raman spectroscopy (SERS) to recognize the suspected alcoholic beverages. High effectiveness (over 98%) of YES/NO classification of the investigated samples was observed when the nonlinear algorithm support vector machine (SVM) was exploited at carefully adjusted detection parameters. The method can identify illicit alcohol within minutes. 相似文献
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In Finland and Poland, a total of 352 (192 boys and 160 girls) 17-year-old general secondary and vocational school students participated in a study investigating their anticipated transition to adulthood. In times of large sociohistorical change in both countries, Finland (economic depression) and Poland (change from socialism to market economy), we investigated to what extent those changes were reflected in the students' probability estimations (for potential goal attainment in three future life domains; education, occupation and family life), generational comparison (attaining a life different from the life of parents), future time extension (for anticipated events in those life domains), and self-evaluations (self-esteem and control over future). The results showed that girls in both countries expressed a higher level of probability for success in education than boys did. As expected, vocational school students in both countries expressed a lower probability of success in future occupation than general secondary school students did. General secondary school students from both countries expressed higher levels of self-esteem and control over future than vocational school students did. Unexpectedly, no differences between boys' and girls' probability estimations for family life were found, in either country. However, girls from both countries anticipated an earlier and more rapid transition to adulthood than boys did, thus reflecting social time tables. The results suggested that the educational track remains a significant stratifying factor in times of societal change in both countries. 相似文献
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A large literature has developed in which labor market contracts are used to estimate the value of a statistical life (VSL). Reported estimates of the VSL vary substantially, from less than $100,000 to more than $25 million. This research uses meta‐analysis to quantitatively assess the VSL literature. Results from existing studies are pooled to identify the systematic relationships between VSL estimates and each study's particular features, such as the sample composition and research methods. This meta‐analysis suggests that a VSL range of approximately $1.5 million to $2.5 million (in 1998 dollars) is what can be reasonably inferred from past labor‐market studies when “best practice” assumptions are invoked. This range is considerably below many previous qualitative reviews of this literature. © 2002 by the Association for Public Policy Analysis and Management. 相似文献
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The study aims to establish the relationship between body height and the greatest length of the femur. The motive for undertaking these examinations was the lack in the literature of studies that allow -- with reference to the current population of Central Europe -- the reconstruction of height while alive based on measurements of a skeleton. It was decided to examine isolated bones from human remains undergoing forensic autopsy, and belonging to individuals of both sexes whose growth processes had stopped. Examinations were conducted on 91 human bodies from the contemporary Polish population. The research points to a very close relationship between the length of a dead body and the measured greatest length of the femur. This relationship was expressed in nine coefficients of correlation calculated for both sexes. 相似文献