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G B?ssler 《Forensic science international》1986,30(1):29-35
Forensic investigations often demand a clear definition of secretor status. Lewis-typing of secretion stains may help to verify non-secretor results and to identify mixtures of secretions from Le (a-b-) persons and secretors (or non-secretors). Furthermore it gives an additional check on secretor status, determined by ABO-grouping. Few problems may arise, when testing prepared saliva or semen stains. Therefore our interest was focussed on the possibility of Lewis-typing in stains appearing in forensic case work such as cigarette tips, stamps and envelope flaps, semen stains and vaginal swabs, nasal secretion, sweat and urine stains. All stains with the exception of sweat and urine were successfully Lewis-typed. In saliva stains Lewis substances could be determined even after 5 years and in semen stains for at least up to 40 days. 相似文献
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Despite the volume of time officers spend on traffic enforcement encounters, there was limited research exploring how they used their discretion in such interactions. Issues relating to police decision making patterns in the enforcement of motor vehicle laws were particularly salient in light of the on-going debate over racial profiling. This study examined how officers made decisions (in particular, to stop and to sanction) in the course of traffic enforcement. Using field observations and interviews with officers in a small midwestern agency, the authors described the factors and forces that officers used in making discretionary choices. The findings indicated that leniency in sanctioning was very common and that officers expected citizens to be contrite and acknowledge responsibility for their infractions. Implications for larger and more systematic observational studies are discussed. 相似文献
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In 16 medical examiner's cases, which were found to be barbiturate-positive by thin-layer chromatographic screening of the liver, blood barbiturate concentrations were determined by gas chromatography. The corresponding vitreous humor samples were screened by the enzyme multiplied immunoassay technique, the EMIT-st serum barbiturate assay. By using the recommended dilution for detecting serum barbiturates, it was possible to detect barbiturates in vitreous humor at a toxic concentration. By using one fourth the amount of diluent, the barbiturates could be detected also at a therapeutic concentration. The EMIT-st assay proved to be useful in the screening for barbiturates in vitreous humor, a material that is readily available in forensic toxicology. 相似文献
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Supreme Court Ruling Creates More Standing Room in the Already Heated Global Greenhouse Gas Movement
This article reviews the recent April 2, 2007 Supreme Court decision in the Massachusetts v. EPA, a highly important case regarding greenhouse gases. The case centered on the Court's review of EPA's denial of a petition to regulate greenhouse gas emissions from new motor vehicles. The Court required EPA to reconsider its denial. The Court found that. 1) the petitioners have standing to challenge EPA's denial of their petition; 2) the Court has the authority to review the denial of the petition; and 3) the Clean Air Act authorizes EPA to regulate greenhouse gas emissions from new motor vehicles. This article looks specifically at the Court's analysis of standing and jurisdiction by Justice Stevens, who wrote the Court's majority opinion, and two dissenting opinions by Justices Roberts and Scalia. Most interesting is how the closely divided Justices (5 to 4 decision) viewed, very differently, the issues regarding standing, the evidence that emissions from new motor vehicles are causing global warming and harm to Massachusetts, and the agency's judgment in denying the petition. Lastly, the article speculates on the impact of the decision and the current activities taking place at the state and regulated community level involving future regulation, litigation, and opportunities by various companies and coalitions to reduce greenhouse gas emissions. The article then presents five broad areas where companies that emit greenhouse gases should need to maintain or increase awareness to better position themselves in the global greenhouse gas movement. 相似文献
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