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871.
DiZinno JA Lord WD Collins-Morton MB Wilson MR Goff ML 《Journal of forensic sciences》2002,47(6):1337-1339
The isolation, amplification, and characterization of human DNA from hematophagous (blood feeding) and necrophagous (carrion feeding) arthropods have been advanced significantly by the development of polymerase chain reaction (PCR) DNA sequencing methodologies. Historically, DNA technology has been successfully utilized to identify individual hosts upon which species of hematophagous arthropods have fed. The analysis of hematophagous insects' gut content blood meals has led to major advances in medical entomology and vector-borne disease epidemiology. In the forensic arena, the ability to apply similar techniques to insects recovered from badly decomposed remains has been greatly enhanced through the advent of mitochondrial DNA (mtDNA) techniques. Mitochondrial DNA analyses have been utilized to identify both the human remains upon which fly larvae (maggots) have fed and the species of the larvae themselves. The preliminary work detailed here demonstrates, for the first time, the successful application of mtDNA sequencing techniques to the analysis of necrophagous beetle larvae. A small sample of sap beetle larvae, Omosita spp. (Coleoptera: Nitidulidae), was collected from human skeletal remains during anthropological examination and analyzed for human DNA using mtDNA sequencing. The beetle larvae yielded mtDNA matching that of the host human bone. The results detailed here further demonstrate the robust nature of human mtDNA and the ability to recover valuable mtDNA evidence from forensically important, late decompositional stage insect species. 相似文献
872.
873.
Nelson MS Levedakou EN Matthews JR Early BE Freeman DA Kuhn CA Sprecher CJ Amin AS McElfresh KC Schumm JW 《Journal of forensic sciences》2002,47(2):345-349
Quality assurance samples submitted from the NCSBI as part of a contract with TBTG to outsource DNA Database samples showed unexpected discrepancies for the locus D16S539 when all other loci yielded identical results. Discrepancies observed included allele drop out and an imbalance in sister alleles with samples returned from TBTG. This led to a comprehensive review of the technical procedures used between the two laboratories to determine the cause of the discrepancies noted for the locus D16S539, since both laboratories were using the PowerPlex 1.1 typing kit from the Promega Corporation. The NCSBI and the TBTG utilize different extraction methods (organic extraction vs. FTA) and amplification conditions (AmpliTaq vs AmpliTaq Gold), respectively, so the exact cause of discrepancy observed was not immediately apparent. Experiments at the NCSBI associated the observed allele drop out and the imbalance of the sister alleles with the use of AmpliTaq Gold and a hot start procedure. Sequencing data revealed that a point mutation resides on the D16S539 primer-binding site that reaches polymorphic levels in African-American populations. This led to the development of a degenerate primer by the Promega Corporation to detect "missing" alleles when AmpliTaq Gold is used. The degenerate primer was then thoroughly tested to show its efficacy in detecting the "true" D16S539 profile when used. 相似文献
874.
Horswell J Cordiner SJ Maas EW Martin TM Sutherland KB Speir TW Nogales B Osborn AM 《Journal of forensic sciences》2002,47(2):350-353
This preliminary investigation has shown that a soil microbial community DNA profile can be obtained from the small sample of soil recovered from the sole of a shoe, and from soil stains on clothing. We have also shown that these profiles are representative of the site of collection and therefore could potentially be used as associative evidence to prove a link between suspects and crime scenes. Soil community profiles were obtained using the T-RFLP fingerprinting method that uses fluorescent primer technology and semi-automated analysis techniques similar to those used in human DNA profiling in forensic laboratories. 相似文献
875.
This study extends the literature on policy feedback and explores the extent to which public attitudes reflect learning from past government initiatives. We analyze the ways in which feedback mechanisms affecting public attitudes may differ from those earlier identified in the literature. We apply this general analytic framework to help explain variation in public attitudes toward private employer involvement in health care, explore possible causal pathways, and offer some preliminary empirical tests of these hypotheses. There are different levels of public support for the notion of employer obligation involving medical care, long-term care, and the treatment of substance abuse. Our evidence suggests that lessons about the performance of institutions in each of these policy domains represent the most important effect of existing policy on public attitudes. Furthermore, these differences correspond to what one would expect based on our model of policy feedback and cannot be explained by other plausible sources of policy legitimacy. 相似文献
876.
877.
Chronic factitious disorder with physical symptoms, or Munchausen syndrome, is a well-recognized but uncommonly diagnosed psychiatric condition characterized by the deliberate production of signs and symptoms of disease in order to receive medical attention. Clinical suspicion of this disease is rarely confirmed by autopsy, as the patients usually do not die as a consequence of feigning illness. Here we report the autopsy confirmation of a case of a suspected Munchausen syndrome patient who presented with a history of cystic fibrosis. Examination of the lungs demonstrated extensive severe interstitial fibrosis, and polariscopic examination revealed a large quantity of crystalline material throughout the tissue; X-ray diffraction identified the material as talc. Synopses of published cases of Munchausen syndrome presenting as cystic fibrosis, and cases of Munchausen syndrome with pulmonary talcosis are presented as part of the discussion. 相似文献
878.
Eric?J.?Bruns Elizabeth?Moore Sharon?Hoover?Stephan David?Pruitt Mark?D.?WeistEmail author 《Journal of youth and adolescence》2005,34(1):23-30
The current study investigated whether the presence of school-based mental health clinicians in an urban school district was associated with reduced out-of-school suspension rates. Forty one elementary schools with expanded school mental health (ESMH) programs were compared to 41 schools without ESMH programs. Correlational analyses revealed associations between suspension outcomes and several school-level demographic variables including school attendance rate, percent of students in poverty, and percent of nonwhite students in the school. After controlling for these variables, however, results of stepwise linear regressions demonstrated no significant differences between ESMH and non-ESMH schools on suspension outcomes. Results of the current study suggest that the presence of ESMH clinicians will not necessarily impact suspension rates in an elementary school. Targeted and well-implemented approaches to address behaviors that lead to suspension, or school- and system-level policies to provide alternatives to suspensions, will likely be a better route to achieving this outcome. 相似文献
879.
880.
Anderson TG 《The Journal of peasant studies》2001,29(1):1-30
This article examines proto-industrialization and the social relations of production in a rural parish in eastern Westphalia that experienced large-scale outmigration to the American Midwest in the mid-nineteenth century. Relying on local and individual-level Prussian tax and emigration records, the study identifies and analyses the socio-economic background of the migrant cohort in terms of proto-industrial activity and peasant economy. Preceded by the downfall of domestic textile industries due to British industrial competition, outmigration was highly selective, drawing individuals from specific socio-economic niches. Landless sharecroppers - linked by debt and labour obligations to better-off peasants and landlords - were underrepresented in the migration, while smallholding peasants and day-labourers - 'free' to commodify their labour power through the sale of home-produced textile products or seasonal migratory labour - were overrepresented. The findings of the study have implications for an understanding of the localized nature of the relations of production in proto-industrial regions, the historical nature of German emigrations, and the dynamics of the German transition to industrial capitalism in the nineteenth century. 相似文献