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871.
da Silva Junior RC Gomes CS Goulart Júnior SS Almeida FV Grobério TS Braga JW Zacca JJ Vieira ML Botelho ED Maldaner AO 《Forensic science international》2012,221(1-3):113-119
Recent information from various sources suggests that a new illicit drug, called "oxi", is being spread across Brazil. It would be used in the smoked form and it would look like to crack cocaine: usually small yellowish or light brown stones. As fully released in the media, "oxi" would differ from crack cocaine in the sense that crack would contain carbonate or bicarbonate salts whereas "oxi" would include the addition of calcium oxide and kerosene (or gasoline). In this context, this work presents a chemical profiling comparative study between "oxi" street samples seized by the Civil Police of the State of Acre (CP/AC) and samples associated with both international and interstate drug trafficking seized by the Brazilian Federal Police in Acre (FP/AC). The outcome of this work assisted Brazilian authorities to stop inaccurate and alarmist releases on this issue. It may be of good use by the forensic community in order to better understand matters in their efforts to guide local law enforcement agencies in case such claims reach the international illicit market. 相似文献
872.
Song J Vorburger TV Ballou S Thompson RM Yen J Renegar TB Zheng A Silver RM Ols M 《Forensic science international》2012,216(1-3):168-182
In response to the guidelines issued by the American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB-International) to establish traceability and quality assurance in U.S. crime laboratories, a NIST/ATF joint project entitled National Ballistics Imaging Comparison (NBIC) was initialized in 2008. The NBIC project aims to establish a National Traceability and Quality System for ballistics identifications in crime laboratories within the National Integrated Ballistics Information Network (NIBIN) of the U.S. NIST Standard Reference Material (SRM) 2460 bullets and 2461 cartridge cases are used as reference standards. 19 ballistics examiners from 13 U.S. crime laboratories participated in this project. They each performed 24 periodic image acquisitions and correlations of the SRM bullets and cartridge cases over the course of a year, but one examiner only participated in Phase 1 tests of SRM cartridge case. The correlation scores were collected by NIST for statistical analyses, from which control charts and control limits were developed for the proposed Quality System and for promoting future assessments and accreditations for firearm evidence in U.S. forensic laboratories in accordance with the ISO 17025 Standard. 相似文献
873.
Konstantinova SV Normann PT Arnestad M Karinen R Christophersen AS Mørland J 《Forensic science international》2012,217(1-3):216-221
A morphine to codeine ratio greater than unity (M/C>1) has been suggested as an indicator of heroin use in living individuals. The aim of this study was to examine the morphine to codeine ratio in a large population (N=2438) of forensically examined autopsy cases positive for 6-monoacetylmorphine (6-MAM) and/or morphine in blood and/or urine. Blood and urine concentrations of 6-MAM, morphine and codeine were examined using GC-MS and LC-MS/MS methods. In 6-MAM positive samples, the M/C ratio was greater than unity in 98% (N=917) of the blood samples and 96% (N=665) of the urine samples. Stratification of 6-MAM negative cases by M/C above or below unity revealed similarities in morphine and codeine concentrations in cases where M/C>1 and 6-MAM positive cases. Median blood and urine morphine concentrations were 8-10 times greater than codeine for both groups. Similarly to 6-MAM positive cases, 25-44 year-old men prevailed in the M/C>1 group. In comparison to cases where M/C ≤ 1, the M/C ratio was a hundred times higher in both 6-MAM positive and M/C>1 cases. The range of morphine concentration between the lowest and the highest quintile of codeine in M/C>1 cases was similar to that in 6-MAM positive cases. This range was much higher than for M/C ≤ 1 cases. Moreover, linear regression analyses, adjusted for age and gender, revealed a strong positive association between morphine and codeine in 6-MAM positive and M/C>1 cases. The M/C ratio appeared to be a good marker of heroin use in post-mortem cases. Both blood and urine M/C>1 can be used to separate heroin users from other cases positive for morphine and codeine. 相似文献
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Grigorii V. Golosov 《欧亚研究》2014,66(10):1611-1628
This study examines the limits of electoral engineering in a consolidating authoritarian regime by focusing on the case of the Imperiali highest averages method of proportional seat allocation in Russia's regional legislative elections. The Imperiali method strongly disadvantages the opposition. But, in the absence of political constraint or trends towards liberalisation, most of the regional decision makers still chose a more permissive formula. The trade-off among the incentives to solidify the power monopoly, to maintain the democratic façade of the regime and to co-opt the opposition was achieved by rejecting the least permissive electoral formula and choosing a middle-of-the-road solution instead. 相似文献
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