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911.
P J Knudsen 《Zeitschrift für Rechtsmedizin》1988,101(4):219-227
The Très Haute Vitesse (THV) bullet was introduced to meet the requirements of law enforcement officers, as an alternative to larger calibre fully jacketed bullets, since expanding or exploding bullets are not relevant in Europe. To examine the effect of the THV bullet in tissue, especially the size of the lesion and the degree of overpenetration, 11 recently killed pigs were shot with the weapons used by the Danish Police Force and a 9-mm pistol for reference. The ammunition was THV in the calibres 7.65 mm, 0.38, and 9 mm, using conventional fully jacketed bullets for comparison. The lesions were considerably larger when the THV bullet was used, the entry wound in particular, being roughly twice the diameter in the case of the THV bullet as compared to the fully jacketed bullet of similar calibre. Only one 7.65-mm THV bullet overpenetrated the target when fired against the thorax or abdomen of the pigs and then with only minimal residual energy. All fully jacketed 7.65-mm bullets, all 0.38 bullets, with the exception of one THV bullet, and all 9-mm bullets overpenetrated the target. The 7.65-mm THV bullet produced a lesion which in its extent resembled that of the fully jacketed 9-mm bullet, and should be a suitable alternative for the Danish Police Force. 相似文献
912.
P. Brett Hammond 《Policy Sciences》1984,16(3):227-243
It is well-known that modelers and policy analysts gain access to policymaking arenas based on what they know. Therefore, critics of models are quick to employ various types of technical standards when evaluating policy models in order to assess validity and reliability of claims to knowledge. This article argues that, in the effort to make models better, overreliance on technical standards misses the important political and policy reasons to model: models call attention to the modelers and to their advice about important policy problems of the day. In this sense, models are used as symbols, as claims to authority, whether or not the underlying knowledge is technically up to snuff. Drawing on the experience of energy policy models, this article explores the problem of models as knowledge versus models as symbols and it examines the muddle that conflicts between them produce. 相似文献
913.
The absorption-elution technique with low ionic strength solution (LISS) and papain-treated test cells previously used for bloodstains was employed for the detection of ABO antigens on human hair. Antigen identification was always possible, with good intensity of agglutination, even in those cases where classic techniques had given false-negative results. It was possible to obtain positive results with fragments of human hair as small as 0.2 cm. 相似文献
914.
The sensitivity and specificity of a zinc spot test for the detection of semen were compared with those of an acid phosphatase detection method. As screening techniques both tests were found to be very sensitive, but the zinc test was more specific and was more reliable in older and especially in deteriorated specimens. It is concluded that the zinc spot test deserves at least the same place as the acid phosphatase test in the primary investigation of suspected semen stains and might well be the test of choice in older and poorly preserved stains. 相似文献
915.
K J O'Connell H A Frazier M A Clark P J Christenson B T Keyes A Josselson 《Journal of forensic sciences》1988,33(2):410-417
An animal model was designed to evaluate the ability of the standard military flak jacket to protect the kidneys from direct ballistic trauma. Yorkshire swine were anesthetized and their flanks were protected by flak jackets. Ballistic insults ranging from a low-velocity handgun to a high-velocity rifle were evaluated. The results demonstrate that a flak jacket provides adequate protection against low- and mid-velocity projectiles since none of the animals from this group had evidence of internal trauma and because only minor superficial surgical attention would have been required. Survivability in each case was considered to be excellent. The flak jacket failed to provide any protection against several types of high-velocity bullets. These weapons caused severe internal injury to the genitourinary system as well as to other major organ systems. Survival would have been unlikely. 相似文献
916.
High technology transfer and computer education: Lessons drawn from the case of a developing country
Dr. John P. van Gigch 《The Journal of Technology Transfer》1984,8(2):57-68
Argentina is a developing country which at present is faced with the advent of high technology and the computer age. In Argentina, like for that matter elsewhere, technology is outrunning our capability to understand it and to take full advantage of its potential. This report describes the conditions prevailing in Argentina to assess the potential impact of high technology in education. Recommendations to implement a program of technology transfer in a typical developing country are drawn. In addition, some of the shortcomings of computer education in Argentina as well as in the United States are indicated. 相似文献
917.
918.
Toxicology analyses and other forensic science data were used to examine the mechanisms through which ethanol increased the risk for death caused by injected street preparations of heroin. The authors studied 505 victims of fatal heroin overdose and compared subjects who had concentrations of blood ethanol greater than 1000 mg/L (n = 306) with those who had concentrations less than, or equal to 1000 mg/L (n = 199). We found significant negative correlations between concentrations of ethanol and morphine (a heroin metabolite) in blood (R2 = 0.11, P = 0.0001 for log10-transformed variables) as well as between concentrations of blood ethanol and bile morphine (R2 = 0.16, P = 0.0001 for log10 bile morphine versus blood morphine). Toxicologic evidence of infrequent heroin use was more common in decedents with blood ethanol concentrations greater than 1000 mg/L than in those with lower concentrations. Our data suggest that ethanol enhances the acute toxicity of heroin, and that ethanol use indirectly influences fatal overdose through its association with infrequent (nonaddictive) heroin use and thus with reduced tolerance to the acute toxic effects of heroin. 相似文献
919.
920.