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781.
Comparing skeletal structures between antemortem and postmortem chest radiographs is widely used by forensic specialists from many disciplines to positively identify unknown decedents. However, validity assessments of this method have been fairly limited. This study had three objectives: 1) to quantify the reliability of ante- and postmortem chest radiograph comparison for decedent identification; 2) to identify useful radiologic features supporting decedent identification; and 3) to recognize sources of error in decedent identification related to use of comparative radiographs. A forensic pathologist, a forensic anthropologist, and two radiologists participated in the study. Our results showed that chest radiograph comparisons proved reliable, if basic decedent information was provided, and antemortem and postmortem radiographs were adequately positioned and exposed. A "morphological approach" using normal anatomical structures for comparison may provide the most efficient method for accurate identification. 相似文献
782.
Validation of a 16-locus fluorescent multiplex system 总被引:24,自引:0,他引:24
Krenke BE Tereba A Anderson SJ Buel E Culhane S Finis CJ Tomsey CS Zachetti JM Masibay A Rabbach DR Amiott EA Sprecher CJ 《Journal of forensic sciences》2002,47(4):773-785
STR multiplexes have been indispensable for the efficient genotyping of forensic samples. The PowerPlex 16 System contains the coreCODIS loci, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, THOI, TPOX, vWA, the sex determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E. This multiplex satisfies the locus requirements for most national databases and is the most efficient currently available system due to its single PCR amplification. To provide the groundwork for judicial acceptance, including the publication of primer sequences, and to evaluate laboratory-to-laboratory variation, a developmental validation for casework on this commercially available system was performed in 24 laboratories and produced the following conclusions. Amplification was reliable on a variety of thermal cyclers and product could be analyzed on either an ABI PRISM 310 Genetic Analyzer or an ABI PRISM 377 DNA Sequencer. Genotyping using single source samples was consistent between 0.25 and 2 ng of input DNA template with a few laboratories obtaining complete genotypes at 0.0625 ng. However, heterozygote allele imbalance (<60% peak height balance) caused by stochastic effects was observed at a rate of 13% with 0.125 ng DNA and 22% at 0.0625 ng DNA. Mixture analyses were done using a total of 1 ng of DNA template. Most alleles were detected in mixtures of 4 to 1 and some minor alleles were detected in mixtures of 19 to 1. Optimum amplification cycle number was dependent on the sensitivity of the detection instrument used and could also be adjusted to accommodate larger amounts of DNA on solid supports such as FTA paper. Reaction conditions including volume, annealing temperature, and concentrations of primer, AmpliTaq Gold, and magnesium were shown to be optimal yet robust enough to withstand moderate variations without affecting genotype analysis. Environmental, matrix and standard source analyses revealed an ability to obtain complete genotypes in all sample types except those exposed to 80 degrees C for 12-48 days. Finally, comparison of genotype results from the PowerPlex 16 System with other commercially available systems on non-probative reference and forensic samples showed consistent results. 相似文献
783.
Between 1976 and the middle of 2001, approximately 718 human executions occurred in the U.S. (a small segment of worldwide executions). Data regarding the medical aspects of these executions are not readily available. We searched all public domain data in the U.S. to obtain specific data for all persons executed in the U.S. since 1976. Of the five methods of execution used (lethal injection, lethal gas, electrocution, hanging, and firing squad), significant differences emerged as measured by rate of complications, duration of time spent by the condemned in the "death chamber," as well as duration of time from the onset of execution procedures to pronouncement of death. These data suggest that human executions are difficult to carry out. Human executions are associated with significant physical complications. These data may help inform future discussions on human executions. 相似文献
784.
A simple technique is presented for the longitudinal sectioning of hair samples without the need for any embedding medium. The technique applies to single hair samples that are placed in a groove of a particular depth and can either be scraped or cut to the desired level. Planar sections are obtained that reveal the internal structure of the sample and are ideal for the application of surface analytical techniques for the study of internal transverse and longitudinal distributions of xenobiotics. 相似文献
785.
786.
The relationship between ethanol and risk of heroin overdosage was studied. Statistical processing of the results of forensic chemical analysis (460 expert evaluations) carried out in Chelyabinsk Regional Bureau of Forensic Medical Expert Evaluations in 2000 was carried out. The results of morphine and ethanol measurements in the blood and urine from corpses where deaths ensued from narcotic or ethanol poisoning, were analyzed. The concentrations of morphine in the blood and urine were measured on a gaseous chromatographer with mass-selective detector (Hewlett Packard HP 6890/HP-5972). Methods for measuring urinary and blood morphine are described. The results of statistical analysis demonstrated relationships between the age and ethanol concentrations in the blood and urine; blood ethanol and total urinary and blood morphine concentrations; blood concentration of free morphine and presence of 6-monoacetylmorphine in the blood. The authors conclude that the presence of ethanol in the blood together with morphine drastically augments the risk of rapid death from respiration arrest. It can also lead to a relatively high risk of overdosage in experienced narcomaniacs using heroin and ethanol. 相似文献
787.
Crystallographic analysis of the cerebrospinal fluid (CSF) was carried out in 18 cases of death from coronary disease and 19 cases of death from ethanol poisoning. The crystallograms were evaluated visually and by the stereoscopic picture. Specific features of the CSF crystal colonies growth in subjects dead from the above conditions are determined. 相似文献
788.
789.
790.
Torres MC Osuna E Pérez-Cárceles MD Gómez-Zapata M Luna A 《The American journal of forensic medicine and pathology》2002,23(2):155-158
The authors evaluated the usefulness of the postmortem biochemical analysis of ionic ratios in different parts of the heart and their relation to cardiac damage caused by chest trauma, as observed by anatomopathologic study. Fifty-nine 59 cases were studied, selected from routine necropsies, and samples were taken from different sites of cardiac tissue. The cause of death was trauma in 40 cases and nontraumatic causes in 19 cases. The object of this study was to analyze the levels of Na+, K+, Ca+2, Mg+2, and Zn+2 in different zones of the heart, and the relationship between intracellular and extracellular ion ratios and the different causes of death and any anatomopathologic alterations observed. The biochemical tests revealed a possible relation between the ionic values and cause of death. Alterations in cell membrane permeability and corresponding modification of the ionic ratios were produced earlier than histologic alterations, which need longer to establish themselves whether or not they follow a traumatic process. 相似文献