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31.
Eighteen external quality assessment (proficiency testing) samples were prepared from client specimens collected with the Intercept® oral fluid collection device and by spiking drug-free oral fluid. Samples were circulated in pairs at quarterly intervals to 13 UK and USA based laboratories for analysis by a panel of OraSure micro-plate Intercept® enzyme immunoassay kits and hyphenated mass spectrophotometric techniques. During the survey, there was a single case of non-specificity in a false report for methadone. The major errors were of lack of sensitivity relative to the concentration thresholds specified for the immunoassays. The sensitivity for overall ‘present’/‘not found’ reports calculated as true positives/(true positives + false negatives) were for the amfetamine specific assay 50%, methyl-amfetamines 93%, barbiturates 64%, cannabinoids 73%, cocaine and metabolites 100%, benzodiazepines 69%, methadone 95%, opiates 79% (opiates excluding oxycodone 93%), phencyclidine 93% and human gamma-globulin 97%. A small number of the sensitivity errors were attributable to errors in chromatographic confirmation techniques. 相似文献
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In Garcia v. San Antonio Metropolitan Transit Authority (1985),Justice Harry Blackmun held that the Tenth Amendment does notprevent the Congress from subjecting state and local governmentsto the provisions of the Fair Labor Standards Act, concludingthat the "political safeguards offederalism" are generally adequateto protect state interests on the national scene. This articleexamines the intellectual foundations of the "political safeguardsof federalism" and finds them inadequate. It then surveys thepost-Garcia scholarship to ascertain whether an alternativetheory of the Tenth Amendment has emerged. Concluding that ithas not, the author suggests the need for afresh approach inview of the hints contained in Justice Sandra Day O'Connor'sopinion in Gregory v. Ashcroft (1991) that five justices maybe ready to reexamine the central thesis of Garcia. 相似文献
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Andrew Ridgway John A. Thompson Jonathan Haslam Simon Page Richard Moore 《Cambridge Review of International Affairs》1990,4(2):56-63
William C. Green and Theodore Karasik (Eds.), Gorbachev and his Generals: The Reform of Soviet Military Doctrine (Westview Press, 1990, 239pp. ISBN 0–8133–7898–2)
Daniel Patrick Moynihan, On the Law of Nations (Harvard University Press, 1990)
Peter J. Stavrakis, Moscow and Greek Communism, 1944–1949. Cornell University Press, Ithaca and London. 1989. ISBN 0–8014–2125–X.
Scalpino, R.A., The Politics of Development: Perspectives on Twentieth‐Century Asia (Harvard University Press, Cambridge, Mass., 1989, pp.131)
Sean M. Lynn‐Jones, Steven E. Miller and Stephen van Evera (Eds.), Soviet Military Policy (MIT Press, 1989. £26.95 [cloth]; £13.50 [paperback]). 相似文献
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The “tragedy of the commons” is the familiar problem that open access to a common property resource leads to overexploitation and to zero profits. A commons model is applied to an example of state sponsored private violence, the practice of privateering or licensed piracy. It is predicted that the presence of uncertainty about the value of the prey will reduce the amount of exploitation effort, and that industry profits may be positive due to both uncertainty and heterogeneous exploiters. Using data from England's wars with France and Spain between 1625 and 1630, the model suggests that the commons, represented by enemy merchant shipping, was not overexploited and that privateering profits were positive. The dynamic paths of privateering effort, ships seized, and individual firm profits were, however, consistent with the normal expectation that commons exploitation will peak and fall, as competition drives down returns through entry. “England was never richer than when at war with Spain.” Sir Edward Coke 相似文献