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871.
Legislative votes can be taken by roll call—noting the position of each individual member—or by some form of indication (sitting or standing, shouting yea or nay, etc.)—noting only an aggregate outcome. Cameral rules define one method of voting as the standard operating procedure and how to invoke any alternative voting methods. We develop a series of hypotheses related to position taking to explain why, when procedures would typically lead to a vote taken by indication, legislators choose to vote by roll call—a means that makes it much easier for actors outside the chamber to observe the positions taken by individual legislators and partisan blocs. With data from Argentina and Mexico, we test these hypotheses regarding the strategic choice of vote procedures and their relationship to observed party unity. 相似文献
872.
Palmiere C Binaghi S Doenz F Bize P Chevallier C Mangin P Grabherr S 《Forensic science international》2012,222(1-3):33-39
The aim of this study was to compare the diagnostic value of post-mortem computed tomography angiography (PMCTA) to conventional, ante-mortem computed tomography (CT)-scan, CT-angiography (CTA) and digital subtraction angiography (DSA) in the detection and localization of the source of bleeding in cases of acute hemorrhage with fatal outcomes. The medical records and imaging scans of nine individuals who underwent a conventional, ante-mortem CT-scan, CTA or DSA and later died in the hospital as a result of an acute hemorrhage were reviewed. Post-mortem computed tomography angiography, using multi-phase post-mortem CTA, as well as medico-legal autopsies were performed. Localization accuracy of the bleeding was assessed by comparing the diagnostic findings of the different techniques. The results revealed that data from ante-mortem and post-mortem radiological examinations were similar, though the PMCTA showed a higher sensitivity for detecting the hemorrhage source than did ante-mortem radiological investigations. By comparing the results of PMCTA and conventional autopsy, much higher sensitivity was noted in PMCTA in identifying the source of the bleeding. In fact, the vessels involved were identified in eight out of nine cases using PMCTA and only in three cases through conventional autopsy. Our study showed that PMCTA, similar to clinical radiological investigations, is able to precisely identify lesions of arterial and/or venous vessels and thus determine the source of bleeding in cases of acute hemorrhages with fatal outcomes. 相似文献
873.
Mephedrone is a synthetic derivative of cathinone which is becoming more common on the recreational drug market. Several intoxications following mephedrone abuse have been reported though published papers have focused essentially on analytical approaches for biological fluids and only one has involved a hair sample. After the development and validation of a new method, the first series of positive results for mephedrone in hair specimens is reported here. After decontamination of the hair strand in methylene chloride, hair segments were cut into small pieces with scissors, weighed and incubated overnight in Soerensen buffer pH 7.0 in the presence of deuterated 3,4-methylenedioxymethamphetamine (MDMA) at 40°C. The incubation medium was extracted using ethyl acetate after alkalinisation with 1N sodium hydroxide (NaOH). Before injection, the dry extract was derivatized using a mixture of heptafluorobutyric anhydride/ethyl acetate (100:50, v/v), evaporated and dissolved in ethyl acetate (25μl). After introduction of 1μl of the extract onto a splitless injector, chromatographic separation was achieved on a HP 6890 gas chromatograph equipped with a 5-MS capillary column. Detection was achieved in single ion monitoring mode (m/z 254-119-210 for mephedrone, m/z 258-213 for MDMA-d5) using a 5973 MSD operating in electron impact mode. Sixty-seven hair specimens were tested for mephedrone. Thirteen of them were found positive for mephedrone with concentrations ranging from 0.2 to 313.2ng/mg with a mean concentration of 26.8ng/mg. It was difficult to compare our findings due to a lack of reference data, nevertheless mephedrone seems well incorporated into hair (concentrations in the ng/mg range) like other stimulant drugs such as amphetamines or cocaine. The aim of this work was to develop a specific and accurate method for mephedrone analysis in hair specimens and its application to a large number of samples (n=67). The developed analytical method appears sensitive enough to reveal occasional to regular use of mephedrone. 相似文献
874.
Bresson F Ducouret J Peyré J Maréchal C Delille R Colard T Demondion X 《Forensic science international》2012,217(1-3):113-118
We study in this paper the expanding behaviour of hollow point 9 mm Parabellum projectiles (Hornady XTP(?) and Speer Gold Dot(?)). We defined a deformation rate that takes into account both the diameter increase and the length reduction. We plotted the behaviour of this parameter versus impact velocity (we refer to this curve as the expanding law). This expanding law has been plotted for different gelatin weight ratios and different gelatin block lengths. We completed our experiments with a set of high speed movies in order to correlate the deceleration to the state of expansion and size of the temporary cavity. Our results pointed out that full expansion is reached shortly after the projectile fully penetrates the gelatin. This result shows that the key point to accurately simulate human body interaction with a hollow point projectile is to accurately simulate the interface (skin, skull, clothes thoracic walls). Simulating accurately organs is only an issue if a quantitative comparison between penetration depths is required, but not if we only focus on the state of expansion of the projectile. By varying the gelatin parameters, we discovered that the expanding law exhibits a velocity threshold below which no expansion occurs, followed by a rather linear curve. The parameters of that expanding law (velocity threshold and line slope) vary with the gelatin parameters, but our quantitative results demonstrate that these parameters are not extremely critical. Finally, our experiments demonstrate that the knowledge of the expansion law can be a useful tool to investigate a gunshot in a human body with a semi-jacketed projectile, giving an estimation of the impact velocity and thus the shooting distance. 相似文献
875.
Taroni F Marquis R Schmittbuhl M Biedermann A Thiéry A Bozza S 《Forensic science international》2012,214(1-3):189-194
This paper extends previous research and discussion on the use of multivariate continuous data, which are about to become more prevalent in forensic science. As an illustrative example, attention is drawn here on the area of comparative handwriting examinations. Multivariate continuous data can be obtained in this field by analysing the contour shape of loop characters through Fourier analysis. This methodology, based on existing research in this area, allows one describe in detail the morphology of character contours throughout a set of variables. This paper uses data collected from female and male writers to conduct a comparative analysis of likelihood ratio based evidence assessment procedures in both, evaluative and investigative proceedings. While the use of likelihood ratios in the former situation is now rather well established (typically, in order to discriminate between propositions of authorship of a given individual versus another, unknown individual), focus on the investigative setting still remains rather beyond considerations in practice. This paper seeks to highlight that investigative settings, too, can represent an area of application for which the likelihood ratio can offer a logical support. As an example, the inference of gender of the writer of an incriminated handwritten text is forwarded, analysed and discussed in this paper. The more general viewpoint according to which likelihood ratio analyses can be helpful for investigative proceedings is supported here through various simulations. These offer a characterisation of the robustness of the proposed likelihood ratio methodology. 相似文献
876.
Massonnet G Buzzini P Monard F Jochem G Fido L Bell S Stauber M Coyle T Roux C Hemmings J Leijenhorst H Van Zanten Z Wiggins K Smith C Chabli S Sauneuf T Rosengarten A Meile C Ketterer S Blumer A 《Forensic science international》2012,222(1-3):200-207
A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture. 相似文献
877.
Research has reported that not only characteristics of the perpetrator but also characteristics of the victim influence risk for intimate partner violence (IPV). This would suggest that prevention of repeat abuse could benefit from a focus on both perpetrator and victim characteristics. Knowledge on factors that are within victims' sphere of influence is important because a focus on victim characteristics can help victims to take control of their situations and can thereby empower them. Dynamic victim-related factors are most relevant here as these are factors that can be changed or improved, in contrast to unchangeable static factors. Surprisingly, however, little is known about how victim-related factors affect risk for revictimization of IPV. The current study was conducted among a Dutch sample of 156 female, help-seeking IPV victims. The aim was to examine to what extent prior IPV and, in particular, dynamic victim-related factors influence risk for future IPV. In accordance with the models articulated by Foa, Cascardi, Zoellner and Feeny, we studied how the three key factors from their models-partner violence, victims' psychological difficulties, and victims' resilience-related to risk for IPV revictimization. Results provide support for several key factors (partner violence and victims' psychological difficulties) and, moreover, show which victim-related factors contribute to revictimization risk above and beyond the influence of prior violence committed by a partner against the victim (i.e., victims' prior IPV victimizations). Findings are discussed in terms of recommendations for practice and future research. 相似文献
878.
879.
880.
Charles A. Kupchan 《安全研究》2014,23(2):219-257
The ongoing reallocation of wealth and power from the West to the “rising rest” promises to produce a new pecking order over the course of the next few decades. Although there is a well-developed body of knowledge on the material dimensions of power transitions, existing scholarship provides a much more embryonic intellectual foundation on the normative dimensions of international change. Transitions in the international distribution of power produce not only novel hierarchies, but also novel brands of international order that rest on the social and ideological proclivities of newly powerful states in the system. This article explores the normative dimensions of hegemony by examining the geopolitical, socioeconomic, cultural, and commercial logics that inform different orders. The normative foundations of hegemony are studied across four great powers: the Ottoman Empire, Imperial China, Great Britain, and the United States. The cases reveal that as great powers rise, they as a matter of course seek to push outward to their expanding spheres of influence the norms that provide order within their own polities. Accordingly, today's emerging powers will not embrace the existing international order erected during the West's watch. On the contrary, China and other rising powers will seek to fashion alternative orders based on their own cultural, ideological, and socioeconomic trajectories. If the next international system is to be characterized by a rules-based order rather than competitive anarchy, it will require a new normative consensus that rests on toleration of ideological and political diversity. 相似文献