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51.
52.
G A Grigor'ev V A Lopatin V I Makarov A L Fedorovtsev 《Sudebno-meditsinskaia ekspertiza》1990,33(1):17-18
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
53.
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
54.
55.
Helena Teixeira Paula Proena Alain Verstraete Francisco Corte-Real Duarte Nuno Vieira 《Forensic Science International Supplement Series》2005,150(2-3):205
An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography–mass spectrometry (LC–MS) has been developed and validated for the confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm3, 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC + H+], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d3-THC + H+]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r2 = 0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette®. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette® collection, 26 of the 40 cases had an undetectable THC. 相似文献
56.
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Significance of functional and nutritive pulmonary circulation for vital reactions in the form of embolisms 总被引:2,自引:0,他引:2
G Adebahr 《Zeitschrift für Rechtsmedizin》1988,100(1):55-64
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
59.
Lobbyists, entrenched forces in congress and self-interested friends will try to stymie Clinton's efforts. A look at four key arenas of combat. 相似文献
60.
Vargas Uribe G 《Estudios demográficos y urbanos》1992,7(1):193-222
The author incorporates geographic variables into this study of population dynamics in Michoacan, Mexico, during the eighteenth century. 相似文献