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It has recently been reported that purity of illicit tablets of ecstasy (MDMA) is now high. Our objective was to confirm whether hair of drug users, who request only ecstasy from their supplier, contains MDMA in the absence of other drugs. GC-MS analysis of scalp hair segments disclosed the presence of MDMA in 19 of 21 subjects and amphetamine/methamphetamine in eight subjects. Surprisingly, seven subjects had hair levels of the MDMA metabolite, MDA, equal to or greater than those of MDMA, suggesting use of MDA in addition to that of MDMA. These amphetamine derivatives might be included by clandestine laboratories to enhance effects of the drug cocktail or because of a perception that MDA synthesis might be simpler than that of MDMA. Drug users and investigators examining possible brain neurotoxic effects of MDMA need to consider that "ecstasy" tablets can contain MDA and methamphetamine despite no demand for the drugs.  相似文献   
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Outlined in the paper are outlooks for determining a group affiliation of sperm in traces, left in material evidence, within forensic biological expertise. A technique is suggested to separate the spermatozoids from the vaginal epithelium cells--it has been used up to now in genetics alone. The method involves the available reagents and does not need any extra training. Its elaboration and introduction would resolve one of the most often-encountered issues set by the investigating office.  相似文献   
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This study examined effects of clothing cues on children's identification accuracy from lineups. Four- to 14-year-olds (n = 228) saw 12 video clips of individuals, each wearing a distinctly colored shirt. After watching each clip children were presented with a target-present or target-absent photo lineup. Three clothing conditions were included. In 2 conditions all lineup members wore the same colored shirt; in the third, biased condition, the shirt color of only one individual matched that seen in the preceding clip (the target in target-present trials and the replacement in target-absent trials). Correct identifications of the target in target-present trials were most frequent in the biased condition, whereas in target-absent trials the biased condition led to more false identifications of the target replacement. Older children were more accurate than younger children, both in choosing the target from target-present lineups and rejecting target-absent lineups. These findings suggest that a simple clothing cue such as shirt color can have a significant impact on children's lineup identification accuracy.  相似文献   
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The present study investigated the reliability of Sexually Violent Predator (SVP) civil commitment criteria under Florida's Jimmy Ryce Act. The purpose of the study was to determine if, independently, 2 evaluators would reach the same conclusions about the same client (n = 295). According to civil commitment criteria outlined by the United States Supreme Court (Kansas v. Hendricks, 1997), SVPs must display a mental abnormality predisposing them to sexual violence and a likelihood of future sexual violence. The interrater reliability of 8 DSM-IV diagnoses applied by evaluators to determine whether a client has a "mental abnormality that predisposes him to sexual violence" was found to be poor to fair (kappa = .23 to . 70). The interrater reliability of risk assessment instruments used to determine "likelihood of reoffense" was good (ICC = .77 to .85). The recommendations made by evaluators regarding whether or not to refer a client for civil commitment demonstrated poor reliability (kappa = .54). Implications for practice and policy are explored.  相似文献   
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