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801.
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
802.
803.
Zörntlein SW Kopp A Becker J Kaufmann TJ Röhrich J Urban R 《Forensic science international》2012,214(1-3):113-117
The in vitro production of GHB was observed in freshly collected, untreated whole blood samples using glass BD-Vacutainers and polypropylene S-monovettes. GHB concentrations were determined daily over a period of one week and after 3, 6 and 9 weeks again. Furthermore, the GHB concentration in 40 untreated random whole blood samples stored at 4°C for a longer period of time (10 samples 12 month, 10 samples 24 month and 20 samples 36 month) was also determined. For comparison, the in vitro production of GHB in freshly collected and prepared serum samples was observed. GHB serum concentrations were determined three times over a period of one week and once again after six weeks. Sample preparation was performed by means of methanolic extraction following the precipitation of whole blood and serum samples. A methanolic standard calibration was done in a low range of 0.005-0.1 μg/mL (LOD: 0.004, LLOQ: 0.013). For quantification a spiked blood bank serum with a determined GHB concentration of 0.09 μg/mL was used. Corrected calibrations in the range of 0.09-5.09 μg/mL were used (LOD: 0.08 μg/mL, LLOQ: 0.30 μg/mL), recovery: 91.3% (high level: 4.09 μg/mL) 50.5% (low level: 0.19 μg/mL). RESULTS: Relevant elevation of GHB was observed in all whole blood samples stored in liquid form (4°C or room temperature). In two of the 40 whole blood samples stored over a longer period of time at 4°C, GHB concentrations in the range of 13 μg/mL were even determined. These findings constitute grounds for caution. Even a GHB cut-off level of 5 μg/mL cannot be considered as "absolutely positive" proof of a case of exogenous administration, at least in untreated liquid blood samples in long time storage. However, no significant elevations of GHB were otherwise observed in any of the serum samples independently of storage temperature nor in the whole blood samples that were frozen for storage. CONCLUSIONS: The results suggest that the cut-off for exogenous GHB of 5 μg/mL could be lowered significantly, with the consequence of winning valuable time for the potential victim, but only if serum is collected for GHB determination or if the whole blood sample is frozen immediately after collection and the procedure well documented. 相似文献
804.
Statutes criminalizing behavior that risks transmission of HIV/AIDS exemplify use of the criminal law against individuals
who are victims of infectious disease. These statutes, despite their frequency, are misguided in terms of the goals of the
criminal law and the public health aim of reducing overall burdens of disease, for at least three important reasons. First,
they identify individual offenders for punishment, a paradigm that is misplaced in the most typical contexts of transmission
of infectious disease and even for HIV/AIDS, despite claims of AIDS exceptionalism. Second, although there are examples of
individuals who transmit infectious disease in a manner that fits the criminal law paradigm of identification of individual
offenders for deterrence or retribution, these examples are limited and can be accommodated by existing criminal laws not
devoted specifically to infectious disease. Third, and most importantly, the current criminal laws regarding HIV/AIDS, like
many other criminal laws applied to infectious disease transmission, have been misguided in focusing on punishment of the
diseased individual as a wrongful transmitter. Instead of individual offenders, activities that enhance the scale of disease
transmission—behaviors that might be characterized as ‘transmission facilitation’—are a more appropriate target for the criminal
law. Examples are trafficking in human beings (including sex trafficking, organ trafficking, and labor trafficking), suppression
of information about the emergence of infection in circumstances in which there is a legally established obligation to disclose,
and intentional or reckless activities to discourage disease treatment or prevention. Difficulties remain with justifications
for criminalizing even these behaviors, however, most importantly the need for trust in reducing overall burdens of disease,
problems in identifying individual responsible offenders, and potential misalignment between static criminal law and the changing
nature of infectious disease. 相似文献
805.
806.
Conventional wisdom suggests that dissident groups use terrorism when they face an overwhelmingly more powerful state, yet attacks in developing countries have predominated in the post-Cold War era, suggesting that terrorism is an increasingly weak state phenomenon. Cross-national studies of terrorism find mixed results for how common measures of state capacity influence terrorism. We argue that these indeterminate findings are due in part to a partial understanding of both what constitutes state capacity and how different aspects of state strength or weakness relate to the propensity of groups to use terrorism. We decompose state capacity into two dimensions that we theorize are particularly relevant to dissident groups: military capacity, or the ability to project conventional military force, and bureaucratic/administrative capacity. Our analysis supports the claim that terrorist attacks are more frequently targeted at states with large, technologically sophisticated militaries but less frequently targeted at states with higher bureaucratic and administrative capacity. We also compare two militarily capable states, France and Russia, that have had different recent experiences with terrorism to help illustrate the causal mechanisms involved. Evidence from our models and cases suggest that states can be capable in different ways, and these various capabilities create differing incentives for using terror as a strategic and tactical tool. 相似文献
807.
DANIEL T. RAGAN 《犯罪学》2014,52(3):488-513
The association between delinquent peers and delinquent behavior is among the most consistent findings in the criminological literature, and several recent studies have raised the standards for determining the nature and extent of peer influence. Despite these advances, however, key questions about how deviant behavior is socially transmitted remain unresolved. In particular, much of the research examining peer influence has been limited to peer behavior, despite a rich literature supporting the salience of beliefs, such as expectations and moral approval, in shaping behaviors. In the current study, I model the peer influence and selection processes with longitudinal social network analysis to reexamine the contributions of peer beliefs and behaviors to adolescent drinking. I find evidence that beliefs related to peer drinking have both a direct and an indirect impact on behavior and play an important role in the friendship selection process. These results highlight the importance of understanding how peers influence deviant behavior and suggest that peer beliefs are an important part of this relationship. 相似文献
808.
This article examines how two of Japan’s largest newspapers frame death penalty issues. Through a content analysis of 7,153 Asahi and Nikkei articles in the 66-month period from January 1, 2007 to June 30, 2012, 11 death penalty frames are identified: inevitability, atonement by dying, atonement by living, victims’ rights and emotions, human rights, miscarriage of justice, calls for discussion, life without parole, deterrence, public support, and retribution. In addition to frames, we examined who the main voices are in each article on capital punishment. We found that avoidance and ambivalence are the two main approaches taken by Asahi and Nikkei to cover death penalty issues, and the most surprising finding is the high salience of atonement as a frame for thinking about capital punishment. In Japan, atonement is used to justify (atone by dying) and oppose (atone by living) the death penalty. Although atonement by living in prison and atonement by dying at the gallows imply radically different outcomes, the flexibility of the atonement frame may suggest new possibilities for Japan’s anti-death penalty movement. 相似文献
809.
Jessica Skinner PhD Natalie Langley PhD Malin Joseph MS James Herrick MSA Robert Brown BS Brian Waletzki BS Peter Goguen Dipl T Loukham Shyamsunder PhD Subramaniam Rajan PhD 《Journal of forensic sciences》2023,68(3):757-767
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
810.
It is difficult to evaluate the extent of stress in cases of suspected child abuse/neglect in a medico-legal autopsy. We have previously reported that stress due to abuse/neglect was found to have led to thymic involution. To elucidate the influence upon thymocytes differentiation, we compared the proportion of the thymocyte subpopulation in the thymus of a neglected child with one in an age-matched control obtained from cardiac surgery. We found that the relative number of CD4+ CD8+ double positive (DP) thymocytes decreased in the neglected child. It was presumed that the selective decrease in the number of the immature DP thymocytes with CD3- to low bcl-2low caused the thymic involution in the neglected child. It was suggested that an alteration in the proportion of thymocytes subpopulation might be used as an index of stress in cases of child abuse/neglect. 相似文献