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31.
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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This article outlines the new regionalism movement and its metropolitanagenda, reviews federal efforts to promote new regionalism underISTEA and TEA21, considers how the new federal policieschanged the role of metropolitan planning organizations (MPOs)in transportation planning by examining the MPO for the Louisvillemetropolis, and assesses the MPO process in Louisville. Thelocal decision of whether to build a new bridge across the OhioRiver was a major test of the enhanced MPO process. Federaltransportation policies enhanced regional coordination and cooperationin transportation planning in the Louisville metropolis resultingin a consensus plan to build two bridges across the Ohio River.However, the MPO process did not lead to the development ofa metropolitan-wide interest or perspective. Moreover, the newregionalist agenda was not advanced because sprawl was not afactor in the decision on whether and where to build the bridges. 相似文献
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The decision to leave an abusive relationship: The testing of an alternative methodological approach
Most studies that consider the factors influencing the decision to leave an abusive relationship rely on retrospective, self-report data. In addition to the biased samples that are frequently obtained in such investigations, the methodological shortcomings of survey research limit its explanatory power, particularly when applied to such sensitive topics as family violence. This report introduces an alternative method for studying the decision to leave an abusive relationship. Forty-five men and 68 women were studied using an experimental computer game of an abuse-like relationship. The tendency to leave this relationship was measured under four differing conditions of severity and frequency of abuse. A logit analysis revealed that the frequency of abuse was more consequential to women's decisions to leave, while severity of abuse was more salient for men. In addition, the hypothesized model, including frequency of abuse, severity of abuse, and locus of control, fits well for women but not for men. The implications of these findings, as well as the validity and future application of experimental games, are discussed. 相似文献
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Identification of the driver in two-rider motorcycle accidents. Inguinal contusion-laceration as an indication of the driver 总被引:1,自引:0,他引:1
H Shiono A Akane K Matsubara K Tanabe S Takahashi 《The American journal of forensic medicine and pathology》1990,11(3):190-192
In motorcycle accidents involving two riders, medicolegal identification of the driver is necessary when one or both riders die. It is particularly important in the latter case, because the survivor almost always insists that he or she was not driving. One characteristic injury that distinguishes the driver from the passenger is inguinal contusion-laceration (accompanied internally by pelvic fracture). This injury, caused by collision of the pelvis with the fuel tank, identifies the driver. 相似文献
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