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941.
The clavicle has been described as a useful bone for the metric determination of sex of human skeletal remains in a contemporary, predominantly white, North American forensic sample. In this article, measurements of clavicle and scapula are provided for a contemporary Guatemalan rural indigenous sample of forensic origin. Maximum length and circumference at midshaft of the clavicle, and height and width of the glenoid fossa of the scapula, were measured in 35 female and 62 male clavicles, and in 38 female and 65 male scapulae. Discriminant function analysis was used to study sexual dimorphism in this population with a classification purpose. Leave-one-out method (jackknife) matrices produced classification success rates ranging from 85.6% to 94.8%. A comparison with the North American forensic sample showed low percentages of correctly sexed Guatemalan male clavicles, ranging from 29.4% to 54.9%. The choice of an appropriate standard for the metric determination of sex is a crucial step in forensic anthropology.  相似文献   
942.
Self-immolation is an uncommon method of suicide, and its occurrence in South Africa is thus far unknown. This study aimed to determine the prevalence of self-immolation deaths and to establish a profile of these cases and the circumstances under which this condition occurs. A 5-year (1996-2000) retrospective review at a mortuary in Durban, South Africa, was conducted. Data were obtained from the Department of Forensic Medicine, the Medical Research Council's National Injury Mortality Surveillance System, and police and hospital records. During the study period, there were 12339 nonnatural deaths, of which 696 (5.6%) were suicides. Self-immolation accounted for 69 (0.6%) of all nonnatural deaths and 69 (9.9%) of all suicides. The subjects had a mean age of 31.2 years and were predominantly female (76.8%) and black (81.2%). The mean burn surface area was 63.3%, and the mean injury severity score was 36.9. Accelerant use was documented in 53 (76.8%) of cases, and paraffin was preferred. All cases occurred indoors. The proportion of suicides due to self-immolation in our study is excessive when compared with international studies that report figures between 0.9% and 2.2% of suicides. Additional studies are necessary to further elucidate the reasons for this discrepancy.  相似文献   
943.
Childhood sporting deaths   总被引:1,自引:0,他引:1  
  相似文献   
944.
The authors describe three accidental deaths resulting from occupational hazards involving environmental gas alterations. One involved the displacement of oxygen caused by leakage of liquid nitrogen during the installation of a magnetic resonance imaging system. Two involved elevated environmental carbon dioxide concentrations: dry ice sublimation in a walk-in refrigerator in a research laboratory, and activation of a carbon dioxide fire alarm-extinguisher system by a woman locked in a bank vault. The autopsy findings, scene investigations, and certifications of these deaths, as related to the mechanisms of death, are discussed.  相似文献   
945.
Since 1958 NASA has invested approximately $3.7 billion in life sciences R&D in the support of the successful human space flight program. There are numerous studies documenting the spin-off technologies that can be traced to NASA research and development activities. Most of these studies describe the technologies and their uses; however only a few measure the economic impact of the spin-offs and most of these are benefit/cost studies that tend to overstate benefits or underestimate costs. This study takes a different approach, measuring only economic impacts to the companies that developed successful spin-off products from NASA life sciences investments. A personal interview was conducted with each company and the benefits are conservatively estimated as the value-added by the NASA technology to the company's output and the amount of additional private R&D stimulated by the NASA R&D.This pilot study of fifteen companies, using a very conservative measurement technique, found a large return to companies that have successfully commercialized NASA life sciences spin-off products. Value-added benefits totaled over $3.7 billion in life sciences R&D in the support of the successful human space flight program. There are numerous studies documenting the spin-off technologies that can be traced to NASA research and development activities. Most of these studies describe the technologies and their uses; however only a few measure the economic impact of the spin-offs and most of these are benefit/cost studies that tend to overstate benefits or underestimate costs. This study takes a different approach, measuring only economic impacts to the companies that developed successful spin-off products from NASA life sciences investments. A personal interview was conducted with each company and the benefits are conservatively estimated as the value-added by the NASA technology to the company's output and the amount of additional private R&D stimulated by the NASA R&D.This pilot study of fifteen companies, using a very conservative measurement technique, found a large return to companies that have successfully commercialized NASA life sciences spin-off products. Value-added benefits totaled over 1.5 billion and a NASA R&D total investment in these 15 technologies of 64 million was found to stimulate an additional64 million was found to stimulate an additional 200 million in private R&D.  相似文献   
946.
947.
948.
Ketosis occurs in ketoacidosis or malnourishment. When either is suspected in relation to a death, it may be important to analyze for ketosis at autopsy. We encountered a case where starvation was suspected in a deceased nursing home resident, where the body had been embalmed prior to autopsy. Gas chromatography (GC) was unable to separate acetone from formaldehyde, a component of embalming fluid. The Acetest is a simple test that can detect acetone and acetoacetate in body fluids. We validated the Acetest with GC on vitreous. The Acetest and GC were consistent except at very low levels of acetone or acetoacetate. The sensitivity of the Acetest for acetoacetate in vitreous was 10 mg/dL, consistent with early starvation. Significant interference from embalming fluid did not occur. The Acetest was negative in the described case. The Acetest is a simple and useful test for the detection of ketosis in embalmed autopsies.  相似文献   
949.
Current procedures for human DNA quantitation reach their limit at 150 pg DNA, which is above the limit of the PCR profiling range using Profiler-Plus (Applied Biosystems, CA). This study tested the potential for the use of primate specific Alu sequences in forensic science for the sensitive detection and quantitaion of DNA. A fluorescently labelled primer pair was designed enabling high efficiency amplification of the core Alu sequence within primate DNA. Quantitation was performed by measurement of fluorescence intensity and comparison to a series of standard template DNA amounts via the construction of a standard curve. The new Alu-based quantitation protocol developed has shown its feasibility in more sensitively quantitating (100-2.5 pg) unknown amounts of human DNA for forensic use. The method is compatible with the use and throughput of current forensic procedures.  相似文献   
950.
Six ninhydrin analogues containing oxygen, sulfur, and selenium substituents at the C-5 position, 5-(4-nitrophenyl)ninhydrin, and benzo[f]furoninhydrin were evaluated as fingerprint development reagents. The analogues all showed good fingerprint color development but were not superior to ninhydrin in this respect. The benzo[f]furoninhydrin complex was strongly luminescent at room temperature following zinc complexation, while the remaining analogues required cooling to -196 degrees C to produce optimum luminescence. The benzo[f]furo, nitrophenyl, and methyl selenide analogues showed the best potential as fingerprint reagents with the benzo[f]furo analogue comparing favorably with DFO.  相似文献   
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