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91.
This paper discusses the organization of the first international proficiency test (PT) programme on ketamine (K) and norketamine (NK) in hair samples. The primary objective of the programme was to evaluate the analytical capability of participating laboratories on hair analysis for K and NK via comparison of results. Authentic samples, instead of spiked samples were used in the programme to mimic the analysis of incorporated illicit drugs in real-life situations. Eight of the ten participating medical or forensic laboratories from Australia, France, Hong Kong, Italy, Singapore and the USA returned results to the organizer. Quantification methods from these laboratories were confined to GC-MS and LC-MS/MS. Performance assessment based on z-score indicated that only three laboratories achieved satisfactory results for both the analysis of K and NK. It was concluded that the overall performance of the participating laboratories was fair and there is still room for further improvement. Additional similarly designed PT programmes are recommended to be organized in order to encourage reliable measurements of illicit drugs in hair samples. Taking into account the substantial effect on the consensus values within limited number of data points, a recommendation on the provision of reference values assigned by accurate methods will be of benefit to small size PT programmes in the forensic field. 相似文献
92.
93.
Both Europe and the United States are confronting the challenges of economic and cultural integration posed by immigration. This article uses the ESS and CID surveys to compare transatlantic public opinion about immigrants and immigration. We find more tolerance for cultural diversity in the United States, but we also find that Americans, like Europeans, tend to overestimate the number of immigrants in their countries and tend to favor lower levels of immigration. The underpinnings of individual attitudes are similar in all countries and immigration attitudes are surprisingly unrelated to country-level differences in GDP, unemployment and the number and composition of the foreign born. An implication of these findings is that acceptance of higher levels of immigration, deemed by many to be an economic need, will require both more selective immigration policies and an emphasis on the cultural assimilation of newcomers. 相似文献
94.
95.
March J Schofield D Evison M Woodford N 《The American journal of forensic medicine and pathology》2004,25(1):60-70
Despite a decade of use in US courtrooms, it is only recently that forensic computer animations have become an increasingly important form of communication in legal spheres within the United Kingdom. Aims Research at the University of Nottingham has been influential in the critical investigation of forensic computer graphics reconstruction methodologies and techniques and in raising the profile of this novel form of data visualization within the United Kingdom. The case study presented demonstrates research undertaken by Aims Research and the Department of Forensic Pathology at the University of Sheffield, which aims to apply, evaluate, and develop novel 3-dimensional computer graphics (CG) visualization and virtual reality (VR) techniques in the presentation and investigation of forensic information concerning the human body. The inclusion of such visualizations within other CG or VR environments may ultimately provide the potential for alternative exploratory directions, processes, and results within forensic pathology investigations. 相似文献
96.
97.
DNA analysis of maggot crop contents can be used to identify a missing body or aid entomologists with interpreting evidence used for PMI estimations. Entomological evidence is often collected and preserved to keep identifiable external features intact. The preservation methods currently in use may not be suitable for preserving DNA in the maggot crop for later analysis. In this study, carrion maggots raised on human tissue were preserved under the following 8 preservation conditions: no fluid at -70 degrees C, no fluid at 4 degrees C, no fluid at 24 degrees C, 70% ethanol at 4 degrees C, 70% ethanol at 24 degrees C, 95% ethanol at 24 degrees C, Kahle's solution at 24 degrees C and formaldehyde at 24 degrees C. Maggots were dissected following 2 weeks, 8 weeks and 6 months of preservation. The maggot crops were extracted, human DNA was quantitated, and an attempt was made at amplifying mitochondrial DNA (mtDNA) and short tandem repeat (STR) loci. Both mtDNA and STRs were successfully amplified from maggots stored in ethanol or without any preservation fluid. Formalin-containing preservation solutions reduced the recovery of DNA. The best results were observed from maggots stored without any preservation fluid at -70 degrees C. 相似文献
98.
Civic engagement and collaborative public management are concepts that are defined broadly, making theoretical explication challenging and practical application of empirical research difficult. In this article, the authors adopt definitions of civic engagement and collaborative public management that are centered on the citizen and the potential for active citizenship. Following a historical review of civic engagement in the United States, a conceptual model of five approaches to civic engagement is offered. Citizen-centered collaborative public management is enhanced through these approaches. The authors suggest the need for further empirical research on collaborative public management that is grounded in citizenship action. 相似文献
99.
Jack S. Levy 《Political science quarterly》2002,117(4):697-698
100.
Jack L. Knetsch 《Journal of policy analysis and management》1995,14(1):68-78
Recent empirical studies indicate that many standard economic assumptions used in policy analyses do not reflect people's preferences and choices as well as modifications based on behavioral findings. Differences in the areas of time preferences and the large disparity between valuations of gains and losses illustrate the issues and the distortions that present analyses likely impose. 相似文献