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Ali L  Miller L 《Newsweek》2004,144(2):46-52, 54
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The road to rave     
Ali L 《Newsweek》2001,138(6):54-56
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A GC-MS method has been developed for the detection of amphetamine, methamphetamine, and the ephedrines, in seizures and the urine, based on on-GC condensation (derivatization) with cyclohexanone. The method is simple: the dried seizure material or the urine extract was mixed with cyclohexanone and injected into the GC-MS. The method was found to be superior to the methods based on acyl and trimethylsilyl (TMS) derivatization. Unlike for the acyl and TMS derivatives, the molecular and fragment ions of the cyclohexanone condensation products (cyclohexanone derivatives) were of substantial abundance, a useful property in unambiguous compound characterization. Furthermore, the high stability of the "derivatizing" reagent, cyclohexanone, compared with acyl and TMS derivatizing reagents, is a useful property in method development. The present method has proved selective and, tentatively, sensitive enough in the following areas (where methods based on acyl and TMS derivatization, as tested in this laboratory, have failed): (a) detection of amphetamine as a metabolite of methamphetamine; (b) detection of norpseudoephedrine as a metabolite of pseudoephedrine; (c) detection of amphetamine as an impurity of methamphetamine; (d) detection of cathine (norephedrine) as a constituent of Khat leaves; and (e) differentiation of Khat use from phenylpropanolamine use.  相似文献   
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Due to possible secondary transfer of gunshot residue (GSR) onto a suspect in police custody prior to sampling, a baseline must be created for the amount of GSR present. With an increase of “lead free” ammunition, testing for both gunpowder and primer GSR is relevant. Seventy samples were collected using carbon‐coated adhesive stubs from four Pittsburgh Police Stations and vehicles to investigate these locations as sources of secondary GSR contamination. These seventy samples were analyzed for primer GSR using scanning electron microscopy‐energy‐dispersive X‐ray spectrometry. One primer GSR particle was detected; no sample was classified as positive for primer GSR. These same samples were then analyzed for gunpowder GSR using liquid chromatography coupled to tandem mass spectrometry to test for akardite II, ethylcentralite, diphenylamine, N‐nitrosodiphenylamine, 2‐nitrodiphenylamine, and 4‐nitrodiphenylamine. Ethylcentralite was quantifiable in two test samples. These results suggest there is a negligible potential for secondary transfer of primer and gunpowder GSR.  相似文献   
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The affective profile model was used to investigate individual differences in police personnel perceptions about the working climate and its influences on motivation. The Positive Affect, Negative Affect Schedule (PANAS) was used to assign police personnel, sworn and non-sworn (N = 595), to four affective profiles: self-fulfilling, low affective, high affective, and self-destructive. The work climate was assessed using the Learning Climate Questionnaire (Management Relations and Style, Time, Autonomy and Responsibility, Team Style, Opportunities to Develop, Guidelines on How to do the Job, and Contentedness). Motivation was evaluated using a modified version (to refer specifically to the individual’s work situation) of the Situational Motivation Scale (intrinsic motivation, external regulation, identified regulation, and amotivation). Self-fulfilling individuals scored higher on all work climate dimensions compared to the other three groups. Compared to low positive affect profiles, individuals with profiles of high positive affect scored higher in intrinsic motivation and identified regulation. Self-destructive individuals scored higher in amotivation. Different aspects of the work climate were related to each motivation dimension among affective profiles. Police personnel may react to their work environment depending on their affective profile. Moreover, the extent to which the work influences police personnel’s motivation is also related to the affective profile of the individual.  相似文献   
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There is a paucity of empirical research on the social psychology of justice in educational settings. A few previous studies have predominantly focused on distributive and procedural justice concerns, and knowledge about the role of what have been called informational and interpersonal justice for school outcomes is very scarce. In the present study, data from 227 eighth- and ninth-grade students who participated in a survey study were analyzed to examine the interplay between relational justice concerns (decomposed into procedural, interpersonal, and informational justice), motivation to study, and school achievement. A comprehensive theoretically grounded multi-item measure of informational justice was developed and validated. The results showed that informational justice significantly predicts school grades, and that motivation to study fully mediates this effect. Neither procedural nor interpersonal justice was associated with school grades. The implications of these results for research and practice are discussed in detail.  相似文献   
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