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31.
Telecommunications regulation has experienced a fundamentalshift from rate regulation to increased reliance on compelledaccess, perhaps best exemplified by the Telecommunications Actof 1996's imposition of no fewer than four new access requirements.Unfortunately, each access requirement is governed by a separateset of rules for determining both the scope and the price ofaccess. The resulting ad hoc regime has created difficult definitionalproblems and opportunities for regulatory arbitrage. In thisarticle we propose a system inspired by the discipline of mathematicsknown as graph theory that integrates all of the different formsof access into a single analytical framework. This system separatesdifferent access regimes into five categories: (1) retail access,(2) wholesale access, (3) interconnection access, (4) platformaccess, and (5) unbundled access. It also provides insightsinto how each type of access complicates the already difficultproblems of network configuration and management and introducesinefficient biases into decisions about network capacity anddesign. The approach we propose also provides insights intothe transaction cost implications of the different types ofaccess. Drawing on the Coasean theory of the firm, our approachexamines the tradeoffs between internal governance costs andthe external transaction costs of providing access to offera theory of network boundaries. This framework shows how accessregulation distorts networks' natural boundaries and providesa basis for evaluating whether private ordering through marketswould lead to more efficient network design.  相似文献   
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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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Book Review     
Radical myths and superpower relations in the 1980s

A review of Mark Kaldor, Gerard Holden, and Richard Falk (eds), The New Detente: Rethinking East‐West Relations, Verso, London, 1989.

Paul Taylor and A.J.R. Groom, Global Issues in the United Nations Framework, Basingstoke, Hampshire, The MacMillan Press Ltd., 1989.

Roger A. Coate, Unilateralism, Ideology, and US Foreign Policy: The United States in and out of UNESCO, Lynne Reinner Publishers, London, 1988.

Bary Buzan, Morten Kelstnip, Pierre Lemaitre, Elzbieta Tromer, and Ole Weaver, The European Security Order Recast: Scenarios for the Post‐Cold War Era, Pinter Publishers, London & New York, 1990, pp.x. 282, £8.95 pbk, £30 hbk.  相似文献   

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A definitive explanation of "crib" or "cot" death remains unknown. An unusual incidental autopsy finding of agenesis of the corpus callosum in a case presenting as "near miss" sudden infant death syndrome (SIDS) is discussed. Hitherto, only a single case associated with SIDS has been reported in the literature. The condition may be easily missed outside the interest in neuropathology.  相似文献   
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We report seven fatalities resulting from the ingestion of illicit drugs packaged in condoms, rubber balloons, or plastic bags which were observed in the last 4 years at the Office of the Chief Medical Examiner, State of Maryland. All the victims, with the exception of one, were men ranging in age from 19 to 37 years. There was no racial predominance. No drug paraphernalia was found at any scene. In two cases, seizure-like activity was documented. One victim had recently returned from Nigeria; therefore, Lassa fever was initially suspected. Two of the victims were "body packer" contrabanders who had just arrived from Africa. They used body cavities to hide large amounts of heroin to avoid U.S. Customs. The other five cases were "mini-packers," small-time illicit drug dealers who had swallowed a single bag of cocaine to avoid police detection. The possible mechanism of leaking or rupture of the latex container is discussed.  相似文献   
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Programme based on mathematical model of the process of dead body temperature changing was developed for estimation of postmortem interval. Automatic retrieval of problem solution was performed on programmable microcalculators of "Electronica MK-61" type using adaptive approach. Diagnostical accuracy in case of dead body being preserved in permanent cooling conditions is +/- 3%.  相似文献   
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