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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
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On Sunday 28 April 1996 a lone gunman killed and injured many people at the historic penal settlement ruins at Port Arthur in South Eastern Tasmania, Australia. Thirty-two victims were shot dead and 19 were injured in a short time inside a cafe and along the roadway leading to the site entrance. The gunman then took one hostage to a nearby guest house which was occupied by a married couple. Police stood siege during the night. Early the next day the cottage began to burn and a man suspected to be the gunman eventually ran unarmed from the building with his clothes alight and was arrested. The house burned to the ground. Three bodies were later located in the burnt ruins. Forensic odontology played a role in the retrieval of evidence and identification of the incinerated victims. Lack of antemortem dental records for one victim necessitated the reliance on a single CT scan radiograph for matching with the remains. Fire scene procedures, evidence collection and other issues were reviewed. The overwhelming scale of this tragedy and its adverse effects on the Tasmanian community, especially the victims' families and survivors, cannot be overestimated. While acknowledging this, it is important that lessons are learnt from tragedies such as these. This paper is presented with a view to assisting forensic odontologists in the investigation of complex incidents. 相似文献
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The ultimatum game is a standard instrument for laboratory experimentalists.It has been replicated in a large number of environments andpoints to special considerations for fairness. Although it hasbeen popular in the experimental community, researchers havenot harnessed all the statistical power they should to evaluatethe dynamics at work in this type of a bargaining game. Thisresearch uses two planned treatments, the first involving asignaling condition concerning a subject's "type," and the seconda price effect built into the structure of the game. We findthat there are no significant main effects as a result of thesignaling condition of a subject's type, but that there arestrong effects as a result of the different payoff parameters.Using a variety of multivariate models we find important, nonobviousinteractions with the gender of the subjects. The lesson thatwe take away from this research is that experimentalists canlearn more from data collected in the tightly controlled laboratoryenvironment by using statistical techniques that complementtheir research designs. 相似文献
1000.
Cooper G Wilson L Reid C Baldwin D Hand C Spiehler V 《Journal of forensic sciences》2005,50(4):928-932
The purpose of these studies was to evaluate the performance characteristics of the Cozart Microplate Enzyme Immunoassay (EIA) for the determination of methadone in oral fluid from patients in a drug misuse treatment program. Oral fluid specimens were collected using the Cozart RapiScan Collection system from 198 donors who were receiving treatment for their addiction and were monitored for drug misuse. Oral fluid specimens were also collected from forty volunteer donors who were not drug users. The specimens were analyzed in the laboratory by EIA and then analysed for methadone and its main metabolite EDDP by gas chromatography-mass spectrometry (GC-MS). A total of 103 samples were confirmed positive for methadone. The Cozart Microplate EIA for d-Methadone in oral fluid using a cutoff of 30 ng/mL in diluted oral fluid had a sensitivity of 91.3% +/- 2.8% and a specificity of 100% +/- 1.0% vs. GC-MS. 相似文献