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Abstract: Photo‐ and thermal‐degradation studies on eccrine fingerprint components are presented herein. Dilute distinct solutions of urea, lactic acid, and seven amino acids were deposited on steel coupons and Teflon® disks, exposed to artificial sunlight or heat, extracted, and analyzed. This aim of this study was to determine whether the investigated eccrine components, previously determined to be Raman active for a parallel study, experienced photo‐ or thermally induced degradation, and if so, to determine the rate and identify any detectable products. Neither the amino acids nor urea exhibited photo‐degradation; however, when heated for a period of three minutes, the onset of thermal‐degradation was initiated at 100°C for the amino acids and 100°C for urea. Lactic acid, the major polymerization initiator of superglue fuming, showed photochemical and thermal‐degradation. These results could be used for future development of new latent fingerprint visualization methods, especially when lactic acid is degraded.  相似文献   
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A significant number of medicolegal deaths involve ethanol. Deaths may be related to the acute, intoxicating effects of ethanol, either in decedents or within persons responsible for causing the deaths of others. Additionally, deaths may be related to chronic alcoholism. A chronic alcoholic may display characteristic external features which allow an observer, such as a forensic pathologist or other physician, to conclude that he/she is probably an alcoholic. Herein, the authors report two decedents with a rare condition known as “multiple symmetric lipomatosis” (MSL), which has a strong correlation with chronic alcoholism. Identification of the peculiar features associated with MSL should prompt the forensic pathologist to consider chronic alcoholism as a probable diagnosis.  相似文献   
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The minority threat perspective suggests that the criminal justice system may be one mechanism through which the majority group (i.e. Whites) maintains control of culturally dissimilar minority groups. Although numerous studies have examined the relationship between minority representation and various policing outcomes, few have extended this research to police use of force in the context of stop-and-frisk practices. Using stop, question, and frisk data from the New York Police Department, this study examines (1) whether racial and ethnic composition influences police use of force, and (2) whether an individual’s race/ethnicity interacts with the racial/ethnic composition of a police precinct to produce disparities in police use of force. The results provide partial support for the minority threat perspective.  相似文献   
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Both research and practical experience suggest that alternative forms of data analysis and presentation may affect their use in the policy arena. The variable-wise alternative produces estimates of population parameters through conventional statistical techniques. The case-wise alternative defines and identifies qualitatively distinct types of cases through techniques of numerical taxonomy. In the experiment reported here, variable-wise and case-wise presentations of Census data on poverty were used to compare the effects of the alternatives on policy makers in a priority-setting task. The results show that the case-wise alternative can improve utilization, assimilation, recall, and recognition of the data. Under the circumstances examined here, the case-wise alternative is a practical means of increasing the return on the public's investment in data resources to improve policy decisions.  相似文献   
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Laudanosine, reticuline, codamine, and laudanine are members of the tetrahydrobenzylisoquinoline family of natural products. These alkaloids are present in the opium poppy, Papaver somniferum, and are subsequently found as impurities in clandestinely processed morphine. Morphine is then synthesized to heroin using hot acetic anhydride. During the course of this study, it was determined that these four tetrahydrobenzylisoquinolines undergo degradation to a series of 18 neutral impurities when subjected to hot acetic anhydride. Based on the degradation pathway, these new impurities were categorized into two sets of impurities called the C1-acetates compounds and the stilbene compounds. Synthesis, isolation, and structural elucidation information is provided for the tetrahydrobenzylisoquinoline alkaloids, and the new neutral impurities have been studied. Several hundred authentic heroin samples were analyzed using an established heroin signature program method. This methodology features the detection of trace neutral impurities present in heroin samples. It was determined that all 18 new impurities were detected in various quantities in four different types of heroin samples. Analytical results featuring these new impurities are reported for South American-, Southwest Asian-, Mexican-, and Southeast Asian-type heroin samples. These new impurities, coupled with other established forensic markers, enhance the ability to classify illicit heroin samples.  相似文献   
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