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921.
922.
Andrew Huxley 《The Modern law review》1990,53(3):369-376
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At a recent South Australian rave, results reported to users from on-site pill-testing, using pill-testing kits, were compared with GCMS analysis of a scraping from the same pill. The presence of an ecstasy-like substance or methylamphetamine was correctly reported to users in 100% of pills that contained those substances. However only 11% of pills with combinations of illicit substances had both substances correctly identified. Ketamine was particularly problematic with identification occurring in only 18% of pills and in some instances, the colorimetric response obtained from ketamine was confused with the response from methylamphetamine. This study also allowed a comparison between pill design and composition encountered at the rave with those submitted to the forensic laboratory over a 6-month period including the month the rave was held. MDMA was present in 68% of pills at the rave and 89% of pills submitted by the police. Ketamine was present in 27 and 26% of pills, respectively and was often combined with other substances. The combinations of illicit substances were identical apart from one police-pill seizure that contained MDMA combined with PMA. This combination has not been previously encountered in South Australia. The pill designs observed at the rave differed significantly from the designs on pills submitted for testing by police. These differences limit the use of pill comparison charts as an alternative identification tool to colorimetric pill testing in South Australia. 相似文献
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von Wurmb-Schwark N Mályusz V Simeoni E Lignitz E Poetsch M 《Forensic science international》2006,159(2-3):92-97
Nowadays, more and more paternity cases are carried out investigating only child and putative father, mostly for economical or private reasons. Usually, reliable results can be obtained and the putative father can be included or ruled out with a high certainty. Considerable problems might arise when a relative of the biological father is investigated as being the putative father. In this study, we investigated 164 persons from 27 families creating artificial deficiency cases using the AmpFlSTRIdentifiler kit, which amplifies 15 STRs simultaneously. We analyzed 93 child/biological father pairs and the corresponding uncles, respectively the brothers of the biological fathers. The average paternity probability for the biological father was 99.9699% (paternity index (PI): 3321.26); only in three cases the results were under 99.9%. In five out of 125 child/uncle pairs no STR mismatches were found and paternity probabilities between 99.9726% (PI 3652) and 99.9970% (PI 33,545) were calculated. The average number of excluding loci was 3.4, but in 31.2% of the cases only zero, one or two mismatches were found. When both putative fathers were genetically typed, the biological father usually had a statistically higher paternity probability. Nevertheless, the differences between probabilities for father and uncle were only small. These results show that a reliable investigation of deficiency cases (i.e. child and putative father) seems to be more difficult than generally assumed. Especially in cases with an unknown familiar background and/or when investigating foreigners for immigration purposes, the laboratory expert should include the mother, increase the number of investigated loci or include a second method such as RFLP-analysis, some serological systems or typing of X-chromosome specific STRs to further ascertain the results. 相似文献
927.
A capillary zone electrophoresis (CZE) method was developed for the analysis of amphetamine and 13 amphetamine analogues. A full factorial design was used to screen for important design variables (i.e. carrier electrolyte concentration, pH, and separation temperature), and a modified simplex was employed in a final optimisation step. The resolution values of the target compounds were used as responses in the screening and optimisation phases. This approach made it possible to control the effects of the design variables on the separation of the target compounds. The best results were obtained using a 100mM Tris/phosphate buffer (pH 3.1) at a separation temperature of 10 degrees C, and the analysis time was 23 min under these conditions. After slight modification, the method also enabled baseline resolution of the most commonly encountered amphetamine derivatives, as well as cocaine and heroin, within 7 min. There was a linear relationship between peak area and concentration for all substances, with correlation coefficients in the range of 0.9975-0.9999. Moreover, the technique was repeatable and exhibited relative standard deviation (R.S.D.) values in the ranges of 0.01-0.11% and 0.54-1.60% for relative migration time and corrected peak area, respectively. Lastly, the method was successfully applied to analyse street samples. 相似文献
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929.
The common history of drug abuse in adults with an undetermined cause of death has led us to hypothesize that chronic drug abuse increases the risk of sudden death. To begin evaluating this hypothesis, we conducted a retrospective case-control study of 61 decedents whose cause of death remained undetermined following autopsy matched one to one to a control group of pedestrians or passengers killed in motor vehicle collisions. In 21 pairs, the case subject had evidence of drug abuse but the control did not, and in 5 cases the reverse was true. Analysis showed that individuals with an undetermined cause of death are 4.2 times more likely to have evidence of drug abuse than are victims of a motor vehicle collision. 相似文献
930.