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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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This article outlines the new regionalism movement and its metropolitanagenda, reviews federal efforts to promote new regionalism underISTEA and TEA–21, 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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Correlation between plasma and bone marrow tricyclic antidepressants has not been studied before. Two groups of rabbits were given 10 and 20 mg of desipramine/kg body weight, respectively. Desipramine was administered to the animals once daily by mouth for 5 days. On the fifth day the animals were sacrificed and blood and bone marrow samples were collected and analyzed using a high performance liquid chromatographic (HPLC) method. Data showed that a correlation exists between bone marrow and blood desipramine. The bone marrow desipramine concentration increased as its blood levels increased. The average ratio of bone marrow to blood desipramine +/- S.D. (standard deviation) in both dosage groups was 37.2 +/- 4.46 with a range of 30.99-44.82. This investigation is promising and shows that bone marrow could be used as an alternative tissue in the absence of a suitable blood sample.  相似文献   
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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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The Green River Murder Investigation in King County, Washington, is currently the longest active serial murder investigation in U.S. history. During its course, over 26 separate scenes with from one to five victims each have been processed. The experience of the authors is presented in order to acquaint other agencies with techniques of outdoor scene processing that have evolved during recovery of remains from Green River and other skeletal cases.  相似文献   
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