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21.
The individuality of fibres used to provide forensic evidence--not all blue polyesters are the same.
Fibres used in forensic casework suffer from a disadvantage common to other forms of trace evidence--it is not possible to state with absolute certainty that they originate from a specific source. Target fibre studies, population studies and research on 'blocks of colour' have effectively demonstrated the polymorphism of textile fibres (particularly man-made ones) and have shown that when a fibre is believed to have a specific putative source, the chance that it has originated from a different source purely by coincidence is extremely remote. A study by Houck MM (Houck MM, Inter-comparison of unrelated fibre evidence. Forensic Science International 2003; 135: 146-149) has shown that no coincidental matching fibres were recovered from items of clothing examined in 20 unrelated crimes. The study involved over two million comparisons. This work goes a step further, and using the example of blue polyester fibres shows that even within a very narrow segment of the whole general fibre population, many examples of a specific colour/type of man-made fibre taken from random sources can be compared and the chance of any two being the same is very low. These studies should help to show the specificity and value of transferred fibres in providing forensic evidence. 相似文献
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V.K. Sharma R.K. Jadhav G.J. Rao A.K. Saraf Heeresh Chandra 《Forensic Science International Supplement Series》1991,50(2)
A method has been developed on reverse phase high performance liquid chromatography for simultaneous determination of methyl, ethyl and isopropyl alcohols under refractive index detection using pure water as the mobile phase. A good separation has been achieved between these alcohols. Detector response was linear with a detection limit of 5 mg/100 ml. Recovery studies were performed by adding known amounts of methyl and ethyl alcohols to blood, lung and liver within the range 80–90%. The reproducibility of the results was always >90%. The quantitative distribution of methyl alcohol in postmortem body tissues and fluids has been reported in three cases of poisoning. 相似文献
26.
Drawing on the strategic surprise, warning-response, and foreign policy literature, this article argues that the September 11 terror attacks should be regarded as a strategic surprise and examines a number of key factors that contributed to vulnerability and inhibited vigilance. Three broad explanatory "cuts" derived from the literature—psychological, bureau-organizational, and agenda-political—are deployed to sift through the rapidly expanding empirical record in an effort to shed light on the processes and contextual factors that left the United States vulnerable to the attacks. The article aims to improve our understanding of generic processes and practices that enhance or detract from vulnerability and vigilance. 相似文献
27.
K A Hewadikaram M L Goff 《The American journal of forensic medicine and pathology》1991,12(3):235-240
Decomposition studies were conducted using two carcasses of domestic pigs, Sus scrofa L., 8.4 kg and 15.1 kg in weight, to determine the effects of carcass size on the rate of decomposition, composition of the arthropod fauna, and succession patterns. A total of 46 arthropod taxa were recovered during this study. No size-related differences were observed between carcasses with respect to composition of the arthropod fauna or patterns of succession. A greater number of arthropods were observed attracted to the 15.1-kg carcass, and the rate of decomposition observed was more rapid for the 15.1-kg carcass than for the 8.4-kg carcass. Internal temperatures of the 8.4-kg carcass were more directly related to external ambient temperatures during the fresh and bloated stages of decomposition. During the decay stage, both carcasses generated internal temperatures significantly above ambient temperatures. Following this stage, internal temperatures fell to approximate ambient temperatures during the postdecay and remains stages. 相似文献
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P. Gill C.H. Brenner J.S. Buckleton A. Carracedo M. Krawczak W.R. Mayr N. Morling M. Prinz P.M. Schneider B.S. Weir 《Forensic Science International Supplement Series》2006,160(2-3):90-101
The DNA commission of the International Society of Forensic Genetics (ISFG) was convened at the 21st congress of the International Society for Forensic Genetics held between 13 and 17 September in the Azores, Portugal. The purpose of the group was to agree on guidelines to encourage best practice that can be universally applied to assist with mixture interpretation. In addition the commission was tasked to provide guidance on low copy number (LCN) reporting. Our discussions have highlighted a significant need for continuing education and research into this area. We have attempted to present a consensus from experts but to be practical we do not claim to have conveyed a clear vision in every respect in this difficult subject. For this reason, we propose to allow a period of time for feedback and reflection by the scientific community. Then the DNA commission will meet again to consider further recommendations. 相似文献
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Stephen B. Peterson 《公共行政管理与发展》1991,11(5):491-510
This article examines constraints in development bureaucracies in intensifying the use of microcomputers as they move beyond processing applications to analysing applications. The work is based on the experience of several ministries of the Government of Kenya. Processing applications involve throughput of data and are relatively simple. Analysing applications, in contrast, are more complex and include data assembly, sensitivity analysis, and modelling. The article argues that processing applications are more compatible with the administrative cultures, bureaucratic functions, personnel skill levels and organizational structures of development bureaucracies. Analysing applications are less compatible because they require a level of training and motivation uncommon in development bureaucracies. Analysing applications are further thwarted by constraints in the supply of relevant information and the lack of demand for analysis by decision-makers. A four-cell matrix is developed which explains these constraints. The article concludes with several recommendations for encouraging microcomputer-based analysis, but cautions that processing applications will continue to dominate for the foreseeable future. 相似文献