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PROBLEM: Road traffic injury is the leading cause of death among adolescents in high-income countries. Researchers attribute this threat to driver risk taking, which driver education (DE) attempts to reduce. Many North American authorities grant DE graduates earlier access to unsupervised driving despite no evidence of this being a safety benefit. This theoretical article examines risk taking and DE in relation to an apparent mobility bias (MB) in policymaking. METHOD: The MB is defined, the history and sources of driver risk taking are examined, and the failure of DE to reduce collision risk is analyzed in relation to a potential MB in licensing policies. DISCUSSION: The author argues that DE's failure to reduce adolescent collision risk is associated with a MB that has produced insufficient research into DE programs and that influences public policymakers to grant earlier licensure to DE graduates. Recommendations are made regarding future research on DE and risk taking, coordinated improvements to DE and driver licensing, and a plan to reduce collision risk by encouraging parental supervision after adolescent licensure. IMPACT ON INDUSTRY: Research on adolescent driver risk taking would have direct applications in DE curricula development, driver's license evaluation criteria, graduated licensing (GDL) policies, as well as other aspects of human factor research into the crash-risk problem.  相似文献   
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Water management in Uzbekistan (Central Asia) is facing tremendous challenges. They are rooted in past and present environmental degradation, the socio-economic transition after the breakup of the Soviet Union, and the impacts of climate change. The Uzbek government has initiated reforms in the agricultural and water sectors to steer the socio-economic transition and address the threats of increasing water scarcity and decreasing agricultural productivity. However, despite the urgency of the problems and massive international assistance changes to the water management regime have only been minimal so far. In this paper we identify major structural barriers for adaptation of the water management regime through an analysis of two recent policy processes. Both processes address pressing water management issues such as “coping with extreme events” and “providing water for ecosystems”. They were analyzed using the Management and Transition Framework as well as a group model building exercises with stakeholders on the national, regional and local levels. The analyses reveal a lack of vertical integration across administrative levels of the formal system and a still prevailing strong centralization of water management. Moreover the water management regime is strongly influenced by informal institutions that shape the outcomes of policy processes. The interactions guided by informal institutions provide an informal link between different administrative levels of the regime. However, those informal networks and the social capital embedded in them rather prevent needed changes. The resulting combination of top down institutional change initiated by socio-economic transition and bottom-up consolidation of the existing status quo via informal processes and networks prevents social learning. It also slows down an adaptation process that potentially could lead to a transition towards a more adaptive regime.  相似文献   
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A variety of factors can influence an individual’s choice of within-group spatial position. For terrestrial social animals, predation, feeding success, and social competition are thought to be three of the most important variables. The relative importance of these three factors was investigated in groups of ring-tailed coatis (Nasua nasua) in Iguazú, Argentina. Different age/sex classes responded differently to these three variables. Coatis were found in close proximity to their own age/sex class more often than random, and three out of four age/sex classes were found to exhibit within-group spatial position preferences which differed from random. Juveniles were located more often at the front edge and were rarely found at the back of the group. Juveniles appeared to choose spatial locations based on feeding success and not predation avoidance. Since juveniles are the most susceptible to predation and presumably have less prior knowledge of food source location, these results have important implications in relation to predator-sensitive foraging and models of democratic group leadership. Subadults were subordinate to adult females, and their relationships were characterized by high levels of aggression. This aggression was especially common during the first half of the coati year (Nov–April), and subadults were more peripheralized during this time period. Subadults likely chose spatial positions to avoid aggression and were actively excluded from the center of the group by adult females. In the Iguazú coati groups, it appeared that food acquisition and social agonism were the major determinants driving spatial choice, while predation played little or no role. This paper demonstrates that within-group spatial structure can be a complex process shaped by differences in body size and nutritional requirements, food patch size and depletion rate, and social dominance status. How and why these factors interact is important to understanding the costs and benefits of sociality and emergent properties of animal group formation.  相似文献   
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