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A custom-built ion mobility spectrometer has been used to obtain the IMS spectra of cocaine, heroin, amphetamine sulfate and LSD at different drug concentrations and desorption temperatures. Practical detection limits for these four drugs were obtained as a function of desorber temperature and for heroin as a function of analysis time. Spectral and ionization interferences for each of the four drugs of interest were determined. Spectral interferences by innocuous materials are few; ionization interferences occur only at very high ratios of the mass of innocuous material to that of the drug of interest. 相似文献
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In this article the authors present some preliminary findings from a comparative study of police recorded violent crimes in Stockholm and Basel. They present the first results from a comparative analysis of the situational context, the ecology of crime, and of offender residences in these cities. There is impressive evidence of basic similarities in the situational context of violent crime and the residential distribution of violent offenders. Yet there are also significant differences, some of which may have interesting implications for crime prevention. Firstly, violent crime seems to be more highly concentrated during weekend nights in Stockholm than in Basel. Secondly, they find evidence that the presence of weapons in a community increases the risk of more serious outcomes of violent events. Efforts to reduce the availability of weapons may thus have significant effects on the outcomes of violence, but not necessarily on its frequency. Thirdly, they show that offenders in both cities are highly concentrated in socially disorganised communities with few economic and social resources. 相似文献
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Hédouin V Bourel B Martin-Bouyer L Bécart A Tournel G Deveaux M Gosset D 《Journal of forensic sciences》1999,44(2):351-353
This study concerns the determination of morphine concentrations in fly larvae reared on rabbits administered different concentrations of morphine and a correlation between concentrations of the drug in larvae and tissues. Three rabbits (R1, R2 and R3) were given dosages of 12.5, 25.0 and 50.0 mg/h of morphine over a 3 h period via continuous ear artery perfusion. These dosages and time of perfusion were calculated to create tissue concentrations of morphine similar to those encountered in human death due to overdose. Morphine blood level plateau was attained after 1 h of perfusion. A fourth rabbit was used as a control. To evaluate drug concentrations, tissues were sampled using a coelioscopic technique. Approximately 400 eggs of Lucilia sericata, all of the same age category, were placed in eyes, nostrils and mouth of each rabbit carcass. Larvae and puparia were regularly collected from each rabbit for toxicological analysis. The concentrations of the drug in the tissues sampled were determined to be similar to those normally encountered in human overdoses and were correlated with the dosage of morphine that had been administered. Morphine was detected in all larvae and pupae fed on tissues from carcasses administered morphine, except for puparia from the colony fed on the R1 animal which received 12.5 mg/h dosage of morphine. All samples from the control rabbit were negative for morphine. Concentrations of morphine in larvae reared on rabbit carcasses containing morphine were 30 to 100 times lower than the concentrations found in the tissues. A correlation between the tissue concentrations and larval concentrations was found in only 3rd instar larvae (80 to 140 h following hatching). No correlations were found between administered dosages, tissue concentrations and younger larvae, prepuparial larvae or puparia. 相似文献
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Is local politics local? French evidence 总被引:2,自引:0,他引:2
Abstract. In advanced democracies, are local political decisions determined by local events? Or are they really shaped by national forces? For the United States case, the evidence on this question is mixed. For the French case, the focus here, the evidence is also mixed, but less hard. In fact, for cantonal elections, in many ways archtypical local affairs, relevant systematic findings are virtually absent. We ask whether the cantonal elections of the Fifth Republic can be better understood as national, rather than local, contests. Our analysis leads us to the conclusion that the basic answer is, ‘yes’. There appear several theoretical reasons for this, which we give an account of. Further, we go on to show that cantonal races can actually serve as barometers to forecast upcoming national races. 相似文献
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Journal of Chinese Political Science - It is no secret that EU member states cannot come to terms on a unified China-policy. Most studies on EU-China relations come to the conclusion that... 相似文献