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The complexity of the modern information ecosystem raises many questions for public organizations. In the context of emergency management, information (such as warning messages) is communicated not only from a source of authority to the public but also between members of the public. The authors use a series of storms that affected Oklahoma in the spring of 2016 to test propositions related to how information about tornado warnings reached the public and who received and shared information about the storm, as well as to identify how gender and age mediate the influence that exposure to an extreme weather event has on the sharing of this information. Overall, the authors find that reported exposure to a tornado increases information sharing through a variety of media and technology. The effect of the tornado erases the otherwise present gender gap in sharing information, while it has little effect on the media platforms that are most popular among older respondents.  相似文献   
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Within any type of system, the actors in the system inevitably compete over resources. With competition comes the possibility of conflict. To minimize such effects, actors often will partition the system into geographic territories. It is against the larger ecological backdrop of competition and conflict that we examine territory formation among urban street gangs. Although previous studies have examined the social and built environment where gangs form, and how the presence of a gang influences local levels of violence, we know little about how competitive interactions are tied to the formation and maintenance of gang territories. We use formal spatial Lotka–Volterra competition models to derive hypotheses about competition‐driven territory formation. By using data on 563 between‐gang shootings, involving 13 rival street gangs in the Hollenbeck Policing Division of Los Angeles, we show that violence strongly clusters along the boundaries between gangs in a way that is quantitatively predicted by the theory. The results suggest that even weak competitive interactions between gangs are sufficient to drive gang territory formation without recourse to other processes or assumptions.  相似文献   
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Two hundred seventy-five United States coins were discovered in the stomach of a mentally disturbed individual at autopsy. Many coins containing copper were corroded by prolonged contact with gastric juice, with subsequent absorption and deposition of copper in the liver and kidneys. The patient died from complications related to the acute toxic phase of chronic copper poisoning. A discussion of the case, foreign-body ingestion, gastric bezoars and the mechanism of copper toxicity is presented. To our knowledge, this is the first death due to copper intoxication following a massive ingestion of coins.  相似文献   
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