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Good gas chromatography (GC) separation of molecules is essential for clean gas chromatography/mass spectrometry (GC/MS) confirmation of compounds. The trifluoro derivatives of ephedrine (E) and methamphetamine (MA) coelute on dimethyl silicone capillary columns, such as DB-1, which are most commonly used by chromatographers. Methods are described to separate E and MA to aid GC/MS confirmations of methamphetamine, ephedrine, or both E and MA together, whichever may be present in Enzyme Immunoassay (EIA)-analyzed amphetamine-positive urine samples. The use of the heptafluoro derivatives of E and MA on a DB-1 column, or the trifluoro derivatives of E and MA on a DB-17 column, is suggested for good gas chromatographic separation.  相似文献   
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The Supreme Court early took note of extralegal, “social science” materials in Muller v. Oregon (1908), and a half-century later made specific reference to social science authorities in the famous footnote 11 of Brown v. Board of Education (1954). Since Brown, much has been written about the Supreme Court's use of social science research evidence, but there has been little systematic study of that use. Those writing on the subject commonly focus on areas of law such as jury size, where social science has been used, and have generally assumed that social science information has been utilized in Supreme Court decisions with increasing regularity. Surprisingly little is known, however, about either the justices' baseline use of social science authorities, or many other aspects of their uses of social science information. The focus here is on the citation of social science research evidence in a sample of 240 criminal cases decided during the 30 years between the Supreme Court's 1958 and 1987 Terms. The resulting portrait contributes to a fuller understanding of the justices' use of social science materials, and may ultimately help promote more effective utilization of social science research evidence in Supreme Court decisions.  相似文献   
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One case of the erroneous administration of deslanoside and high level of drug in antemortem plasma and postmortem specimens has been reported owing to the unusual surrounding circumstances. Deslanoside in antemortem plasma was determined by FPIA and the analysis was done by HPLC in the postmortem tissue samples. The analytical results and methods used in the examinations are discussed in the following paper.  相似文献   
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The extent to which local life circumstances influence criminal activity has been the focus of much theoretical debate. Although empirical research has been initiated, it remains limited. Herein, we use data on 524 serious offenders from the California Youth Authority for a seven‐year post‐parole period to examine the relationship between changes in local life circumstances and criminal activity. We extend previous research by employing a statistical model that accounts for the joint distribution of violent and nonviolent crime during the late teens and twenties in order to present information on patterns of criminal activity during a newly recognized developmental period of the life course, “emerging adulthood.”  相似文献   
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