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Marta Concheiro Ana de Castro Oscar Quintela Manuel Lpez-Rivadulla Angelines Cruz 《Forensic Science International Supplement Series》2005,150(2-3):221
This paper describes the analytical methodology for the determination of MDMA, MDA, MDEA and MBDB in oral fluid. After a liquid–liquid extraction, the analysis was carried out by high performance liquid chromatography (HPLC), with fluorescence detection. The detector wavelength was fixed at 285 nm for excitation and 320 nm for emission. The mobile phase, a mixture of phosphate buffer (pH = 5) and acetonitrile (75:25), and the column, Kromasil 100 C8 5 μm 250 mm × 4.6 mm, allowed good separation of the compounds in an isocratic mode in only 10 min. The method was validated and showed good limits of detection (2 ng/mL) and quantitation (10 ng/mL) for all the amphetamine derivatives. No interfering substances were detected. A stability study of these compounds in oral fluid stored at three different temperatures (−18, 4 and 20 °C) over 10 weeks was conducted, showing a time-dependent degradation of the four compounds. 相似文献
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This study investigated the influence of an authority figure on eyewitness identification. Participants watched a staged crime
and then were administered a photo lineup by either an authority (policeman) or non-authority figure (civilian). Participants
in the authority condition were more likely to choose a lineup member than those in the non-authority condition. There was
no effect of authority, however, on the accuracy of the identification decisions. The lack of a deleterious effect suggests
that the presence of a police officer during identification procedures does not create an unduly suggestive situation or have
undesirable effects on eyewitness identification decisions. Although witnesses' choosing behaviors did not increase the rate
of identification errors, the effect of the administrator's authority on choosing was reduced when unbiased instructions (vs.
biased instructions) were presented to the witnesses. Thus, support was found for the use of neutral instructions during eyewitness
identification procedures. 相似文献
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The Federalist claims to present a republican response to thetypical political problems faced by republics. That solutionrequired a departure from all models of republics known at thattime, and in particular a break with Anti-Federalist modelsthat posited heavy reliance on responsibility, understood aseither political accountability or as moral and political virtue.The Federalist challenges the Anti-Federalist notion that a"no-gap polity" is the means to safe and effective republicanism.It also challenges those who believe that virtue of people orrulers is the precondition of a republican polity. Publius doesrequire quasi-virlues of certain sortsand thus does notrely entirely on calculating selfinterestbut these aresignificantly different from the virtues posited by earlierrepublican theorists or certain contemporary interpreters ofThe Federalist. 相似文献
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Drug trade is widely seen as a phenomenon rather new to the Netherlands. However, at the beginning of the 20th century the Dutch pharmaceutical industries were already extensively involved in the production of both opiates and cocaine, and they went on exporting large quantities of these drugs after the Opium Act (1919) took force. Until the 1960s, arrests were not at all common, and these largely affected minority groups like Chinese opium smokers and black marijuana users. Since then, drug control efforts have increased by leaps and bounds. At first, cannabis was the main target; then the focus turned to heroin, and that was later joined by cocaine. This paper traces the history of the drug trade and drug control in the Netherlands, with emphasis on their development in Amsterdam. The conclusion is reached that, in spite of drastic changes in both drug trade and drug control, certain ideologies, constructs and strategies have remained remarkably stable. 相似文献
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