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Forensic entomology requires the fast and accurate identification of insects collected from a corpse for estimation of the postmortem interval (PMI). Identification of specimens is traditionally performed using morphological features of the insect. Morphological identification may be complicated however by the numerical diversity of species and physical similarity between different species, particularly in immature stages. In this study, sequencing was performed to study the mitochondrial DNA (mtDNA) as the prospective basis of a diagnostic technique. The sequencing focused on a section of the cytochrome oxidase I encoding region of mtDNA. Three species of calliphorid (blow flies) commonly associated with corpses in western Australia, Calliphora dubia, Chrysomya rufifacies and Lucilia sericata, in addition to specimens of Calliphora augur and Chrysomya megacephala were studied. Phylogenetic analysis of data revealed grouping of species according to genus. The DNA region sequenced allowed identification of all species, providing high support for separation on congeneric species. Low levels of variation between some species of the same genus however indicate that further sequencing is required to locate a region for development of a molecular-based technique for identification. 相似文献
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Bloodhounds are used to trail fleeing felons and missing persons. In order to start a trail, the dog must be presented with a person's scent. There are many hypotheses on what a bloodhound smells while trailing. The present study attempts to identify whether human scent is genetic, and if it is influenced by one's environment. Bloodhounds trained in human scent discrimination were used to differentiate between monozygotic twins, related and nonrelated persons, living together and apart. The first test required the dogs to run blind trails after being presented with the scent of one person in the pair, while the opposite person was hidden. The second test allowed the dogs to trail one person in the pair after both people were hidden. Results appear to demonstrate that bloodhounds rely heavily on genetic cues when differentiating between people. Environmental cues do not appear to significantly aid the bloodhound in scent discrimination. 相似文献
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Harvey ML 《Journal of forensic sciences》2005,50(3):627-629
An important area of recent research in forensic entomology has been the use of insect DNA to provide identification of insects for fast and accurate estimation of time since death. This requires DNA to be extracted efficiently and in a state suitable for use in molecular procedures, and then stored on a long-term basis. In this study, Whatman FTA cards were tested for use with the Calliphoridae (Diptera). In particular, testing examined their ability to effectively extract DNA from specimens, and store and provide DNA template in a suitable condition for amplification using the polymerase chain reaction (PCR). The cards provided DNA that was able to be amplified from a variety of life stages, and thus appears to be of sufficient quality and quantity for use in subsequent procedures. FTA cards therefore appear suitable for use with calliphorids, and provide a new method of extraction that is simple and efficient and allows for storage and transportation without refrigeration, consequently simplifying the handling of DNA in forensic entomological cases. 相似文献
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Until now, suicide prevention efforts have been limited in developing countries, although there are pockets of excellent achievement. Various universal, selective, and indicated interventions have been implemented, many of which target a different pattern of risk factors to those in developed countries. In the absence of sufficient mental health services, developing countries rely heavily on nongovernment organizations (NGOs) to provide crisis interventions for suicidal individuals, as well as proactive interventions aimed at raising community awareness and building resilience. Often these NGOs work within a social and public health framework, collaborating with others to provide nested suicide prevention programs that are responsive to local community needs. There is a clear need to develop appropriate, relevant and effective national suicide prevention plans in developing countries, since, to date, only Sri Lanka has done so. These plans should focus on a range of priority areas, specify the actions necessary to achieve positive change in these priority areas, consider the range of collaborators required to implement these actions, and structure their efforts at national, regional, and local levels. The plans should also promote the collection of accurate data on completed and attempted suicide, and should foster evaluation efforts. 相似文献
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Books reviewed in this article.
Samuel Bowles, David M. Cordon, and Thomas E. Weisskopf, Beyond the Wasteland: A Democratic Alternative to Economic Decline
Economic Report of the President 1981
Helen Cinsburg, Full Employment and Public Policy: The United States and Sweden
Elliot Jaques, Free Enterprise, Fair Employment 相似文献
Samuel Bowles, David M. Cordon, and Thomas E. Weisskopf, Beyond the Wasteland: A Democratic Alternative to Economic Decline
Economic Report of the President 1981
Helen Cinsburg, Full Employment and Public Policy: The United States and Sweden
Elliot Jaques, Free Enterprise, Fair Employment 相似文献