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971.
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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G Yelin M L Taff G E Sadowski 《The American journal of forensic medicine and pathology》1987,8(1):78-85
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
975.
Elevated levels of carbon monoxide and cyanide serve as evidence of intravital burning in fire victims. Hydrogen cyanide is released by combustion of nitrogen-containing organic material such as plastics and wool. We present a case of a man who died of haemopneumothorax caused by a stab wound. According to several eye witnesses the body was wrapped in a plastic sheet and burned 2 days after death with the aid of gasoline. No coal pigment was observed in the mucosa of the upper airways at autopsy. The blood sample taken from the pulmonary vessels 6 days after death disclosed a level of blood carboxyhaemoglobin of 4% and of blood cyanide of 10 mg/l. The low carboxy-haemoglobin level was consistent with the smoking habits of the victim. The thoracic cavity had been opened by burning of the intercostal soft tissue. This allowed hydrogen cyanide gas to enter the thoracic cavity and diffuse into the blood probably causing the high blood-cyanide level. 相似文献
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A Rightful Place for Public Health in American Law 总被引:1,自引:0,他引:1
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This paper presents a theoretical framework for understanding the investment decisions and financing decisions of financial and non-financial enterprises over the business cycle. At the core of this theoretical framework is an agency problem between relatively more risk averse depositor/bondholders and relatively less risk averse stockholders. The solution to this agency problem is a corporate governance system that takes the form of an up-front contract that directs managers to make portfolio/investment decisions in the interest of their stockholders, and financing decisions in the interest of their depositor/bondholders. This enables depositor/bondholders to offset any risk shifting portfolio/investment decisions made on behalf of the shareholders thereby mitigating the moral hazard problem among debtors and creditors. The Basle Accord on risk-based capital requirements for depository institutions is one particular regulatory application of this more general theoretical framework. The paper concludes with a comparison between the Basle Accord and the 100% reserve or narrow banking proposal as the means of achieving a risk-free medium of exchange and a financial system that facilitates the optimal transfer of resources from savers to investors consistent with society’s aversion towards risk. 相似文献