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In this article a practical case is described when gunshot directions and position of a victim's body at the moment of each shot were determined by natural simulation using an LG-78 laser (made in the form of a gun).  相似文献   
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This study used data from 299 police officers from 12 municipal police departments across the state of Virginia to determine the relationship between education and police performance. Performance was measured by supervisor evaluations of each officer's overall performance, communication skills, public relations skills, report writing skills, response to new training, decision making ability, and commitment to the police department. Significant correlations were found between education and most measures of performance. Most importantly, the results show a significant correlation between overall performance and education (r=24, p.<001). The only variables not proving to be significantly related to education were objective measures of the volume of arrests, number of times the officer required discipline, and number of accidents. Interestingly, the benefits of a college education do not become apparent until police officers gain experience. In addition, police, officers with only a high school diploma decreased in overall performance after five years of experience.  相似文献   
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In the current study the objective was to find to what extent a reliable determination of age at death is made possible by establishing the degree of aspartic acid racemization in the dentin of teeth. The results of the investigation of 46 teeth are in agreement with the values found by other authors. The method presented makes a reproducible and accurate estimation of age possible. We intend to elaborate and improve this promising method for determination of age at death. The relevant points are presented here.  相似文献   
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The functional and nutritive circulation in the lungs is connected by anastomoses between the pulmonary and bronchial arteries. The anastomoses have the structure of blocked arteries from which arteriovenous anastomoses proceed to the peribronchial plexus. The pulmonary artery is provided with a flow impulse by the anastomoses, and oxygen-containing blood is admixed with the venous blood, thus forming an "aortalization" in the lungs. By diverting the bloodstream, venous blood can reach the bronchial artery. The peculiarities of the lung circulation are important for vital reactions in the form of macro- and microembolisms. Macroembolisms prove the functionality of the system if branches of the pulmonary artery are closed before the arteries are blocked. A hemorrhagic infarction either arises or does not arise, and the hemorrhagic infarction cannot exceed a certain limit. A microembolism is over and above the anastomoses. If the microembolism is greater, pressure in the arteria pulmonaris can cause blood from the pulmonary artery to overflow into the bronchial artery. Because arteriovenous anastomoses arise from the blocked arteries, microemboli can now reach the systemic circulation. Thus, the system described can explain the passage of microemboli into the systemic circulation, avoiding the capillaries of the lungs; on the other hand, larger microembolisms can prove the functionality of the system.  相似文献   
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