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791.
Chemical processes involved in the development of latent fingerprints using the cyanoacrylate fuming method have been studied. Two major types of latent prints have been investigated-clean and oily prints. Scanning electron microscopy (SEM) has been used as a tool for determining the morphology of the polymer developed separately on clean and oily prints after cyanoacrylate fuming. A correlation between the chemical composition of an aged latent fingerprint, prior to development, and the quality of a developed fingerprint has been observed in the morphology. The moisture in the print prior to fuming has been found to be more important than the moisture in the air during fuming for the development of a useful latent print. In addition, the amount of time required to develop a high quality latent print has been found to be within 2 min. The cyanoacrylate polymerization process is extremely rapid. When heat is used to accelerate the fuming process, typically a period of 2 min is required to develop the print. The optimum development time depends upon the concentration of cyanoacrylate vapors within the enclosure.  相似文献   
792.
The Mixed Stain Study 1 (MSS1, Apr.-Nov. 1997) and Mixed Stain Study 2 (MSS2, Jan.-May 1999) evaluated multiplexed short-tandem repeat (STR) DNA typing systems with samples containing DNA from more than one source. These interlaboratory challenge studies evaluated forensic STR measurement, interpretation, and reporting practice using well-characterized samples of very different analytical difficulty. None of the relatively few errors reported in either exercise resulted in a false identification of a reference source; several errors in evaluating the unknown source in three-source samples would hinder matching the profile in any archival database. None of the measurement anomalies reported is associated with any particular STR multiplex; all DNA amplification anomalies are associated with inefficient DNA extraction, inaccurate DNA quantitation, and/or analytical threshold policies.  相似文献   
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Methods for measuring a Russian narcotic analgesic prosidol are suggested: thin-layer chromatography, microcrystalloscopy, gaseous chromatography with ionization flame detector, gas chromatography with mass selective detector, ultraviolet spectroscopy, high-performance liquid chromatography with ultraviolet detector, proton nuclear magnetic resonance used in chemical toxicological analysis, pharmacological analysis, and investigation of material evidence pieces.  相似文献   
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Distribution of blood groups by the serum Gm system was studied in Buryats and in the entire population of Buryatia without consideration for the national appurtenance and with consideration for sex. Differences in the incidence of the factors were detected.  相似文献   
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Morphological manifestations of narcomania in heroin users are described. Diseases associated with heroin narcomania and causes of death of heroin users are presented. Morphological manifestations at the site of injections and inflammatory reactions in parenchymatous organs are characterized. The authors pay special attention to the productive inflammation which can serve as one of the signs that confirm narcomania in cases with parenteral injections of crude heroin. The authors refer the granulomas to toxic allergic form of granulomatous hypersensitive inflammation.  相似文献   
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