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排序方式: 共有250条查询结果,搜索用时 31 毫秒
61.
Abstract: Electronic control devices (including the Advanced TASER® X26 model produced by TASER International) incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, effects of monophasic square waves with different parameters were compared with those of the X26 electronic control device, using two animal models (frogs and swine). Pulse power, electrical pulse charge, pulse duration, and pulse repetition frequency affected muscle contraction. There was no difference in the charge required, between the square waveform and the X26 waveform, to cause approximately the same muscle‐contraction response (in terms of the strength‐duration curve). Thus, on the basis of these initial studies, the detailed shape of a waveform may not be important in terms of generating electro‐muscular incapacitation. More detailed studies, however, may be required to thoroughly test all potential waveforms to be considered for future use in ECDs.  相似文献   
62.
Over 70,000 children are ‘looked after’ by local authorities in England and Wales. Emerging research suggests that a significant proportion of their birth parents have either already lost a child to permanent adoption or will go on to lose others. These ‘repeat loss’ cases raise difficult questions about marginalized mothers and their reproductive autonomy. This article considers past and present tactics used by the state in its attempts to limit that autonomy, including institutionalization, sterilization, long‐acting contraception, and permanent adoption. It argues that the gradual democratization of intimate citizenship over the past century, defined as a person's ability to choose and direct their intimate relationships, has obliged the contemporary state to develop new tactics which aim to build personal capacity and to balance enhanced child protection with enhanced reproductive autonomy.  相似文献   
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Gary W. Cox 《Public Choice》1994,78(1):115-124
The models developed here are intended to convince the reader that Tsebelis' results — that increased punishment leaves the equilibrium level of crime unchanged — is an example of what is possible rather than a general result. To recap the argument in words: it is true that raising the penalty on a crime may cause the enforcing agency to divert attention away to other matters, so that theexpected penalty facing the prospective criminal is not as high as it would have been had the agency not adjusted; but it is not generally true that enforcing agencies will choose to lower their probabilities of enforcement just enough to exactly offset the increased penalty, leaving the expected penalty unchanged, hence the equilibrium level of crime unchanged.8 this result sounds unusual when stated in words and it is when modelled using the theory of games too.This work was supported by NSF grant SES-9022882.  相似文献   
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This paper describes a procedure for the determination of psilocin and psilocybin in mushroom extracts using high-performance liquid chromatography with postcolumn chemiluminescence detection. A number of extraction methods for psilocin and psilocybin in hallucinogenic mushrooms were investigated, with a simple methanolic extraction being found to be most effective. Psilocin and psilocybin were extracted from a variety of hallucinogenic mushrooms using methanol. The analytes were separated on a C12 column using a (95:5% v/v) methanol:10 mM ammonium formate, pH 3.5 mobile phase with a run time of 5 min. Detection was realized through a dual reagent chemiluminescence detection system of acidic potassium permanganate and tris(2,2'-bipyridyl)ruthenium(II). The chemiluminescence detection system gave improved detectability when compared with UV absorption at 269 nm, with detection limits of 1.2 x 10(-8) and 3.5 x 10(-9) mol/L being obtained for psilocin and psilocybin, respectively. The procedure was applied to the determination of psilocin and psilocybin in three Australian species of hallucinogenic mushroom.  相似文献   
68.
Three-dimensional computer visualization of forensic pathology data   总被引:1,自引:0,他引:1  
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   
69.
Intraosseous T1-weighted (T1W) and short-tau inversion recovery (STIR) magnetic resonance imaging (MRI) signal intensity changes—so-called bone marrow edema—may be able to differentiate antemortem and postmortem fractures in human forensic imaging. The primary objective of this study was to investigate this hypothesis using an animal model. Three juvenile Landrace pigs were anesthetized and underwent MRI of both tibiae and both radii using a 1.5 T magnet. T1W, T2-weighted (T2W), STIR, and T2* sequences were included. Antemortem fractures were induced in both tibiae and postmortem fractures in both radii, and MRI was repeated. Two board-certified radiologists blinded to fracture group jointly evaluated the images for intraosseous and soft tissue signal intensity changes. Sensitivity (Se) and specificity (Sp) in identifying antemortem fractures were calculated based on intraosseous, soft tissue, and combined intraosseous and soft tissue signal intensity changes. Intraosseous and soft tissue signal intensity changes, when present, were hyperintense in all sequences. Intraosseous hyperintensity in T1W and T2W sequences yielded Sp of 100% for antemortem fractures. Regardless of sequence, soft tissue hyperintensity was comparatively more sensitive than intraosseous hyperintensity. Sensitivity for each sequence could be maximized by assessment of soft tissue and intraosseous hyperintense signals together; for the T1W sequence, such assessment optimized diagnostic utility yielding a Se of 100% and Sp of 83%. In summary, MRI—particularly the T1W sequence—can differentiate antemortem and postmortem fractures and may be a useful adjunct to the forensic analyses of fractures.  相似文献   
70.
Journal of Youth and Adolescence - Mentoring programs, which pair youth with caring, non-parental adults with the goal of promoting positive youth development, are an increasingly popular strategy...  相似文献   
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