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851.
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   
852.
On request of the International Criminal Tribunal for the former Yugoslavia (ICTY), the Danish-Swedish forensic teams worked in Kosovo during the summer and the fall of 1999. The teams worked mainly as "mobile teams" at sites with few graves. Only two larger sites were examined. Most of the bodies were buried separately. A few "multiple burial" graves were examined, but no mass graves were encountered. The main purpose of the autopsies was to establish the cause and manner of death. Identification was of less importance, but a majority of the bodies had been identified prior to the autopsy. A total of 308 bodies, mainly males, were examined. The age varied greatly with a mean age of 47 years. The most common cause of death was gun shot wounds and the most common manner of death was homicide.  相似文献   
853.
Forensic medical service is constantly updated, which is confirmed by introduction of new modern methods, such as detection of blood or semen with test strips, new modifications of methods for handling bone material, differentiation of blood of the same group within ABO system, identification of blood groups in mixed stains of blood of humans and some animals, use of gel plates, etc. Methodological and information letters have been issued and field seminars are regularly carried for upgrading expert biologists. The overwhelming majority of expert biologists have received specialized education and topical upgrading.  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   
856.
Gas chromatographic conditions for qualitative and quantitative evaluation of acetonitrile in biological material were determined, including those for reactive gas chromatography. Absolute and relative time of acetonitrile and concomitant substances retention in three columns of different polarity was determined. Study of the time of acetonitrile retention in biological material showed that acetonitrile concentration in the blood virtually did not change in cadaveric material stored in a hermetically closed flask for 2 weeks at 20 +/- 3 degrees C, while its concentration in the stomach decreased by 10-15%. Distribution of acetonitrile in human viscera in lethal poisoning was studied; the agent was evenly distributed in the gastric wall, intestine, liver, and kidney, while its concentrations in the lung and brain were 2-3 times higher. Forensic chemical expert analyses of the blood, urine, and viscera from corpses of humans dead from lethal acetonitrile poisoning showed that lethal concentration in the blood was 28.3-57.0 mg and in the urine 23.2-40.6 mg/100 ml.  相似文献   
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Theories of judgment in decision making hypothesize that throughout adolescence, judgment is impaired because the development of several psychosocial factors that are presumed to influence decision making lags behind the development of the cognitive capacities that are required to make mature decisions. This study uses an innovative video technique to examine the role of several psychosocial factors—temporal perspective, peer influence, and risk perception—in adolescent criminal decision making. Results based on data collected from 56 adolescents between the ages of 13 and 18 years revealed that detained youth were more likely to think of future-oriented consequences of engaging in the depicted delinquent act and less likely to anticipate pressure from their friends than nondetained youth. Examination of the developmental functions of the psychosocial factors indicates age-based differences on standardized measures of temporal perspective and resistance to peer influence and on measures of the role of risk perception in criminal decision making. Assessments of criminal responsibility and culpability were predicted by age and ethnicity. Implications for punishment in the juvenile justice system are discussed.  相似文献   
860.
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