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排序方式: 共有920条查询结果,搜索用时 15 毫秒
81.
This paper is the fifth in a series of six in relation to the development of a harmonised method for the profiling of amphetamine [L. Aalberg, K. Andersson, C. Bertler, H. Borén, M.D. Cole, J. Dahlén, Y. Finnon, H. Huizer, K. Jalava, E. Kaa, E. Lock, A. Lopes, A. Poortman-van der Meer, E. Sippola, Development of a harmonised method for the profiling of amphetamines I. Synthesis of standards and compilation of analytical data, Forensic Sci. Int. 149 (2005) 219-229; L. Aalberg, K. Andersson, C. Bertler, M.D. Cole, Y. Finnon, H. Huizer, K. Jalava, E. Kaa, E. Lock, A. Lopes, A. Poortman-van der Meer, E. Sippola, J. Dahlén, Development of a harmonised method for the profiling of amphetamines II. Stability of impurities in organic solvents, Forensic Sci. Int. 149 (2005) 231-241]. The third paper [K. Andersson, K. Jalava, E. Lock, L. Aalberg, Y. Finnon, H. Huizer, E. Kaa, A. Lopes, A. Poortman-van der Meer, M.D. Cole, J. Dahlén, E. Sippola, Development of a harmonised method for the profiling of amphetamines III. Development of the gas chromatographic method, Forensic Sci. Int., in press] dealt with the optimisation of the gas chromatographic and detection methods whereas the fourth paper [K. Andersson, K. Jalava, E. Lock, Y. Finnon, S. Stevenson, L. Aalberg, H. Huizer, E. Kaa, A. Lopes, A. Poortman-van der Meer, M.D. Cole, J. Dahlén, E. Sippola, Development of a harmonised method for the profiling of amphetamines IV. Optimisation of sample preparation, Forensic Sci. Int., in press] concerned the optimisation of the extraction method prior to GC analysis. This paper is a study of the optimised method in order to determine its stability. Investigations of within and between day variations were carried out in four laboratories. Moreover, variations between laboratories were also determined. Both flame ionisation detector (FID) and MS detection were used. One laboratory studied nitrogen-phosphorous detector (NPD) detection as well. For this task, 12 batches of amphetamine were prepared. Six of them were synthesised via the Leuckart route, three via the nitrostyrene route and three via the reductive amination route [A.M.A. Verweij, Impurities in illicit drug preparations: amphetamine and methamphetamine, Forensic Sci. Rev. 1 (1989) 2-11]. Taking into account all studied target compounds and the average results from four laboratories, the within day variation was around 6% for FID and 5% for MS, the between days variation was around 10% for FID and 8% for MS. For NPD detection, within day variation was 5% and between days variation 9% (only one laboratory). Finally, the inter-laboratory variation was about 12% for FID (four laboratories) and 10% for MS (three laboratories).  相似文献   
82.
Community capacity for organization and collaboration has been shown to be a powerful tool for improving the health and well-being of communities. Since 1994 the Washington State Family Policy Council has supported the development of community capacity in 42 community public health and safety networks. Community networks bring local communities together to restructure natural supports and local resources to meet the needs of families and children, and increase cross-system coordination and flexible funding streams to improve local services and policy. In this study, researchers sought to demonstrate the strong impact of the community networks' capacity to interrupt health and social problems. Findings suggest that community networks reduce health and safety problems for the entire community population. Further, community networks with high community capacity reduced adverse childhood experiences (ACE) in young adults ages 18-34.  相似文献   
83.
The paper assesses the influence of electoral rules on vote choice and election outcomes using a quasi-experiment conducted during a recent Canadian provincial election. Respondents were invited to vote under three voting systems (first past the post, alternative voting and proportional representation) and to answer a short questionnaire. We examine how the distribution of votes and seats is affected, and we ascertain how much of the total difference is due to psychological and mechanical effects. We find that a PR system would have increased legislative fractionalization by the equivalent of one effective party and that the mechanical effect is much more important than the psychological effect. As for AV, its mechanical and psychological effects act in opposite directions.  相似文献   
84.
Abstract: The growth in popularity of flying ultralight aircraft and paragliding has been associated with an increased involvement of Emergency Medical Services because of various types of trauma suffered from both inexperienced and skilled individuals. This case presentation reports on a paraglider pilot, who was seen spinning “unusually” rapidly toward the ground, without visible attempts to regain control of the aircraft. Besides the bilateral mydriasis and the absence of any ECG activity, there was a significant swelling of face, lips, neck, and tongue. Upon opening the mouth, a dead bee was found over the tongue, underneath the palate. A fatal anaphylactic shock was the likely cause of death of the pilot while still “in mid‐air.” This case is certainly different from the commonly reported accidents during paragliding. An updated review of the medical literature shows no reported cases of fatal anaphylactic shock during the practice of paragliding.  相似文献   
85.
Gunshot residue (GSR) is commonly analysed in forensic casework using either scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) or gas chromatography-mass spectrometry (GC-MS). Relatively little work has been reported on the post-discharge GSR content of non-metallic inorganic or low molecular weight organic anions to distinguish between different ammunition types. The development of an analytical method using suppressed micro-bore anion exchange chromatography (IC) is presented for the analysis of GSR. A hydroxide gradient was optimised for the separation of 19 forensically relevant organic and inorganic anions in <23min and sensitivities of the order of 0.12-3.52ng of anion detected for all species were achieved. Along with an optimised extraction procedure, this method was applied to the analysis of post-ignition residues from three selected ammunition types. By profiling and comparing the anionic content in each ammunition residue, the possibility to distinguish between each type using their anionic profiles and absolute weight is presented. The potential for interference is also discussed with respect to sample types which are typically problematic in the analysis of GSR using SEM-EDX and GC-MS. To the best of our knowledge this represents the first study on the analysis of inorganic anions in GSR using suppressed ion chromatography.  相似文献   
86.
Spatial and Temporal Patterns of Terrorist Attacks by ETA 1970 to 2007   总被引:3,自引:0,他引:3  
Rational choice perspectives maintain that seemingly irrational behavior on the part of terrorist organizations may nevertheless reflect strategic planning. In this paper we examine spatial and temporal patterns of terrorist attacks by the Spanish group ETA between 1970 and 2007. Our analysis is guided by a public announcement by ETA in 1978 that the group would shift from emphasizing attacks in the Basque territory to instead launch attacks more widely in the hopes of exhausting the Spanish government and forcing it to abandon the Basque territory. This announcement suggests that prior to the end of 1978 ETA attacks were based mostly on controlling territory in the Basque region that they hoped to rule; and after 1978 the organization decided to instead undertake a prolonged war of attrition. Accordingly, we argue that before the end of 1978 ETA was mostly perpetrating control attacks (attacking only within the Basque territories) and that the diffusion of attacks between provinces was mostly contagious (spreading contiguously). After the 1978 proclamation, we argue that the attack strategy shifted toward attrition (attacking in areas outside of the Basque territories) and that the attacks were more likely to diffuse hierarchically (spreading to more distant locations). As predicted, we find that after ETA moved toward a more attrition based attack strategy, subsequent attacks were significantly more likely to occur outside the Basque region and to target non-adjacent regions (consistent with hierarchical diffusion). We also find that hierarchical diffusion was more common when a longer time elapsed between attacks (a likely consequence of the fact that more distant attacks require more resources and planning) and that attacks against Madrid were unlikely to be followed immediately by more attacks on Madrid or surrounding provinces. After ETA announced a shift in policy, they maintained a highly dispersed attack strategy even during their period of decline. Using information about where and when prior attacks occurred could provide useful information for policy makers countering groups like ETA.  相似文献   
87.
A physical fit is an important observation that can result from the forensic analysis of trace evidence as it conveys a high degree of association between two items. However, physical fit examinations can be time-consuming, and potential bias from analysts may affect judgment. To overcome these shortcomings, a data analysis algorithm using mutual information and a decision tree has been developed to support practitioners in interpreting the evidence. We created these tools using data obtained from physical fit examinations of duct tape and textiles analyzed in previous studies, along with the reasoning behind the analysts' decisions. The relative feature importance is described by material type, enhancing the knowledge base in this field. Compared with the human analysis, the algorithms provided accuracies above 90%, with an improved rate of true positives for most duct tape subsets. Conversely, false positives were observed in high-quality scissor cut (HQ-HT-S) duct tape and textiles. As such, it is advised to use these algorithms in tandem with human analysis. Furthermore, the study evaluated the accuracy of physical fits when only partial sample lengths are available. The results of this investigation indicated that acceptable accuracies for correctly identifying true fits and non-fits occurred when at least 35% of a sample length was present. However, lower accuracies were observed for samples prone to stretching or distortion. Therefore, the models described here can provide a valuable supplementary tool but should not be the sole means of evaluating samples.  相似文献   
88.
Forensic fractographic features of bone reliably establish crack propagation in perimortem injuries. We investigated if similar fracture surface features characterize postmortem fractures. Experimentally induced peri- and postmortem fractures were used to assess if fractographic features vary as bone elasticity decreases during the postmortem interval (PMI). Thirty-seven unembalmed, defleshed human femoral shafts from males and females aged 33–81 years were fractured at varying PMIs with a drop test frame using a three-point bending setup and recorded with a high-speed camera. Vital statistics, cause of death, PMI length, temperature, humidity, collagen percentage, water loss, fracture energy, and fractography scores were recorded for each sample. Results showed that fractographic features associated with perimortem fractures were expressed in PMIs up to 40,600 accumulated degree hours (ADH), or 60 warm weather days. Hackle was the most consistently expressed feature, occurring in all fractures regardless of ADH. The most variable characteristics were wake features (78.4%) and arrest ridges (70.3%). Collagen percentage did not correlate strongly with ADH (r = −0.04, p = 0.81); however, there was a strong significant correlation between ADH and water loss (r = 0.74, p < 0.001). Multinomial logistic regression showed no association between fractographic feature expression and ADH or collagen percentage. In conclusion, forensic fractographic features reliably determine initiation and directionality of crack propagation in experimentally induced PMIs up to 40,600 ADH, demonstrating the utility of this method into the recent postmortem interval. This expression of reliable fractographic features throughout the early PMI intimates these characteristics may not be useful standalone features for discerning peri- versus postmortem fractures.  相似文献   
89.
ABSTRACT

This article reports the findings of a small-scale qualitative study exploring the experiences of autistic adults who have had experience of the family justice system. While participants related some positive elements to their experiences, in particular with regard to the willingness of professionals to try to learn more about their clients’ needs, the overall picture showed significant concerns. The reports given showed significant misunderstandings about autism, and a system which struggled to make appropriate adjustments which would allow autistic court users to have access to justice on an equivalent basis to non-autistic litigants. This situation stands in contrast to the position regarding other disabilities in the Family Justice System, but also to the relatively greater level of provision for autistic people within the Criminal Justice System. Based on participants’ experiences and existing good practice in other areas, we make recommendations that could be adopted by the Family Court and practitioners.  相似文献   
90.
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