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The development of less-lethal technologies has provided law enforcement personnel with an alternative to lethal force. Although the less lethal projectile was produced to engender non-penetrating wounds, case studies show that there have been a number of reported penetrating injuries ranging from minor to significant in morbidity. The objective of this study was to determine the energy per unit area required to penetrate various regions of the body. Eight unembalmed postmortem human specimens were procured for this testing. Each specimen sustained a maximum of 25 impacts consisting of shots to the anterior and posterior thorax, abdomen, and legs. A 12-gauge, fin-stabilized, rubber rocket round was used as the impactor for all of the conducted tests. The energy density required for 50% risk of penetration varied from 23.99 J/cm2 for the location on the anterior rib (p = 0.000) to 52.74 J/cm2 for the location on the posterior rib (p = 0.001). 相似文献
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Kathleen Gallagher Cunningham Marianne Dahl Anne Frugé 《American journal of political science》2017,61(3):591-605
Why do organizations choose to use nonviolence? Why do they choose specific nonviolent tactics? Existing quantitative work centers on mass nonviolent campaign, but much of the nonviolence employed in contentious politics is smaller‐scale nonviolent direct action. In this article, we explore the determinants of nonviolence with new data at the organization level in self‐determination disputes from 1960 to 2005. We present a novel argument about the interdependence of tactical choices among nonviolent options in self‐determination movements. Given limitations on their capabilities, competition among organizations in a shared movement, and different resource requirements for nonviolent strategies, we show that organizations have incentives to diversify tactics rather than just copy other organizations. The empirical analysis reveals a rich picture of varied organizational resistance choices, and a complex web of interdependence among tactics. 相似文献
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Bret L. Billet Jan Knippers Black Daniel H. Levine Maristella Botticini Allan C. Reddy Lawrence S. Graham Harvey Glickman Fred H. Lawson Thomas U. Berger Paul W. Kuznets Yuan-li Wu Marianne A. Ferber Stephen P. Mumme Dilmus D. James Alison Brysk Carrie A. Meyer Juan M. del Aguila Robert W. Anderson Walter C. Opello M. C. Hallberg Luth Tweenten Anderson Professor 《Studies in Comparative International Development (SCID)》1994,29(3):84-126
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One hundred and fifty-five cord cells were tested for the red blood cell antigens Lua, Lub and Cob in order to collect data on the early postnatal expression of these markers. Additionally, dosage studies were carried out in 8–10-month-old heterozygous children. Antigens Lua and Lub revealed to be significantly less expressed in children of both ages compared with those of their mothers, whereas no such differences could be demonstrated in the expression of the antigen Cob. 相似文献
89.
The resilience of autocratic regimes in various world regions and the emerging model of illiberal capitalist autocracies (China, Russia) have led scholars to shift their attention to the durability of such regimes. Autocracies not only resist the global spread of democracy, but are developing their own domestic efforts in the promotion of autocracy. This study argues that processes at the regional level aim at the dissemination and diffusion of autocratic norms, structures, processes, policy approaches or practices. Likewise, we propose that authoritarian gravity centres can be attributed with both the active promotion of autocracy as well as the inducement of diffusion effects. Our research tries to shed some light on their strategies and modes of influence on countries in their geopolitical proximity (target states). 相似文献
90.
Amber R. Rose MSFS Monica Joshi PhD Marianne E. Staretz PhD Matthew Wood PhD Thomas A. Brettell PhD 《Journal of forensic sciences》2023,68(4):1148-1161
Aminoindanes are a class of novel psychoactive substances (NPSs) that have become more prevalent over the past decade. GC–MS is often utilized for identifying seized drugs and is well regarded for its ability to separate mixtures. However, certain aminoindanes have similar mass spectral data and require specific gas chromatographic stationary phases for separation. Derivatization is an alternative method that can be applied to GC–MS to enhance chromatographic results, providing more selective analysis in seized-drug identification. This study investigates derivatization techniques to provide options for forensic science laboratories in accurately identifying aminoindanes. Three derivatization reagents, N-methyl-bis(trifluoroacetamide) (MBTFA), heptafluorobutyric anhydride (HFBA), and ethyl chloroformate (ECF) were evaluated for the analysis of eight aminoindanes by GC–MS using two common gas chromatographic stationary phases, Rxi®-5Sil MS and Rxi®-1Sil MS. All three derivatization methods successfully isolated eight aminoindanes, including the isomers 4,5-methylenedioxy-2-aminoindane (4,5-MDAI), and 5,6-methylenedioxy-2-aminoindane (5,6-MDAI) that could not be differentiated prior to derivatization. Reduced peak tailing and increased abundance were observed after derivatization for all the compounds, and mass spectra of the derivatives contained individualizing fragment ions that allowed for further characterization of the aminoindanes. This excluded 4,5-MDAI and 5,6-MDAI as they shared the same characteristic ions and were only distinguishable by their retention times. All three derivatization techniques used in this study allow for successful characterization of the aminoindanes and give forensic science laboratories flexibility in their analysis approach when they encounter these compounds. 相似文献