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Known exemplar samples of human DNA have traditionally been body fluids, such as blood, saliva, and semen. In each case, the presence of water is a risk for the bacterial growth, which may degrade the DNA evidence. In this study, the authors have developed a method that employed a hydrophilic adhesive tape (HAT) for collecting DNA evidence. The HAT method was used to remove surface cells from relatively hairless areas on the body. The area examined were ankle, arm, behind the ear, between fingers and back of the neck. The HAT was then dissolved in the extraction buffer. DNA typing was performed at vWA, THo1, F13A1, and FES loci using the short tandem repeat (STR) analysis. Our results show that the samples collected from ear give the best results with a success rate of 100%. All subjects tested by this method had known STR genotypes established from buccal swabs. The authors' results suggest that the HAT method can be used as a less invasive method for collecting biological evidence for forensic DNA analysis. In addition, this collection method should reduce the risk of DNA degradation due to the moisture, which is encountered using conventional collecting methods. 相似文献
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Potassium permanganate is used for the production of cocaine and methylcathinone. The third convention of the UN against narcotic drugs (1988) contains a list of so-called precursors, substances commonly used for the production of narcotic drugs. The control of the precursors can be a very important step to prevent the illicit production of narcotic substances. A chemical characterization of a seized product may contribute to determine the origin of the producing company and the trade channels and to prevent further illicit deliveries. 31 samples of permanganate (19 authentic and 12 seized samples) have been analyzed for 9 metallic elements. Detailed procedures for the emission spectrography and ICP-analysis are given and the range of concentrations is tabulated. It was surprising that no significant concentrations of metals like chromium, nickel or cobalt were present. Nor was the difference between the technical and analytically pure products sufficient to make a differentiation according to origin. This is probably attributable to the technical manufacture of permanganate by electrolysis. All the statistical analyses of the results performed on the available data do not allow conclusions as to the country of origin or manufacturer, as production batches of one and the same manufacturer may also show differences. Only the morphology of the product (crystals, powder or "free flowing") allows a certain characterization. Nevertheless it seems necessary to analyze all seized samples for impurities and to establish a table of "impurity profiling" in the future in order to receive more information and to find correlations in selected cases. 相似文献
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Until mid-2003, the audit tool developed at the Australian National University to measure compliance with the International Guidelines on HIV/AIDS and Human Rights had not been tested in a developing country. This article describes the process and preliminary findings from the application of the audit in Cambodia. Of particular interest was the willingness of the Cambodian government to permit the audit, as well as the publication and dissemination of the results. 相似文献
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