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531.
Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed “behind armor blunt trauma” (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400–460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear.  相似文献   
532.
Medium‐chain acyl‐CoA dehydrogenase (MCAD) deficiency is a rare but important component of the differential diagnosis for adults with a history of premortem mental status changes and the postmortem finding of hepatic steatosis. This case report describes a 30‐year‐old white man who, following a period of nausea and vomiting, was admitted to the hospital with sudden mental status deterioration followed rapidly by clinical deterioration and death. Treating physicians in this case suspected acute illicit drug toxicity with synthetic cathinones based on social history. Clinicians and medical examiners should be aware that the presentation, signs, and symptoms described may indicate an underlying inborn error of metabolism such as MCAD deficiency and take action accordingly.  相似文献   
533.
The institutional landscape for public land management in the U.S. West underwent a seismic shift in the 1990s as the long‐dominant resource extraction paradigm was replaced by the ecosystem management paradigm. Here we analyze the efforts of community‐based organizations (CBOs), entities that emerged in some locations across the West to help their respective communities navigate the transition from resource extraction to environmental stewardship. Despite their formal status as civil society actors, in practice CBOs came to fill various institutional gaps by taking on roles traditionally assigned to both the state and the private sector. We use a case study approach to examine how the Hayfork, California–based Watershed Research and Training Center engages in institutional work within a setting that is at once both open and constrained, as the rural community within which it operates lacks strong state‐ or industry‐led development trajectories while remaining constrained by the legacies of past institutions.  相似文献   
534.
Accumulated evidence from dozens of cash transfer (CT) programs across the world suggests that there are few interventions that can match the range of impacts and cost‐effectiveness of a small, predictable monetary transfer to poor families in developing countries. However, individual published impact assessments typically focus on only one program and one outcome. This article presents two‐year impacts of the Zambian Government's Child Grant, an unconditional CT to families with children under age 5, across a wide range of domains including consumption, productive activity, and women and children's outcomes, making this one of the first studies to assess both protective and productive impacts of a national unconditional CT program. We show strong impacts on consumption, food security, savings, and productive activity. However, impacts in areas such as child nutritional status and schooling depend on initial conditions of the household, suggesting that cash alone is not enough to solve all constraints faced by these poor, rural households. Nevertheless, the apparent transformative effects of this program suggest that unconditional transfers in very poor settings can contribute to both protection and development outcomes.  相似文献   
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Davis  Douglas D.  Reilly  Robert J. 《Public Choice》1999,100(1-2):31-38
Nitzan's (1991) analysis of differential sharing rules in a collective rent-seeking setting is reconsidered. Two groups, each with more than one member, are presumed to use different linear combinations of two sharing rules, one based on an equal-division of the prize, and the other on each member's relative effort. We show that an equilibrium always exists for this type of game, and then characterize the equilibrium. Our result is contrary to Nitzan's claims that (a) in the general case an equilibrium often does not exist, and (b) an equilibrium never exists when the groups use the polar extreme rules.  相似文献   
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Review article     
The Burning Question, Michael Simmonds, Adam Smith Institute, 1989, pp. 43, £9.00.  相似文献   
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