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151.
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   
152.
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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154.
This study examines demographic growth and change in Tilleur in the valley of Meuse in Belgium during 1807-80 during the process of industrialization and urbanization. The proportion of immigrants (foreigners and Flemings) increased from 15% in 1807 to 65% in 1856. After 1856, population and industrial growth stabilized. During 1856-66 the proportion of natives stabilized, and the proportion of Flemings increased. It is argued that in Tilleur there were two phases: a foundation phase of industrial and population growth and a phase of maturation with decreased non-native population and greater similarity between groups. Immigrants contributed to the birth rate in greater proportions than their proportion in the population of Tilleur. During 1847-66 native population increased annually from 2.4% to 3.8%. Migrants' annual increases were diminished by the effects of mortality but expanded by the influence of in-migration. During 1857-66 the proportion of foreigners declined and marked the transition to a new phase. During 1830-66 the sex ratio grew from 93 to 119. During the Industrial Revolution in Tilleur, women shifted from outnumbering to undernumbering men. The iron and coal in the region attracted men. The sex ratio among the Flemish was 214 in 1866. In 1830 the proportion of fertile women was higher among immigrants and declined thereafter. Age at marriage rose for natives and declined for immigrants. The native population structure by sex, age, and marriage did not favor the birth rate. During 1866-80 the birth rate of foreign immigrants and rural natives declined, the birth rate of natives doubled, and the gap between these two groups narrowed. The changes among immigrants during the foundation phase led to fertility decline in the maturation phase. Marriage and migration interactions linked the industrial revolution with the demographic transition.  相似文献   
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Dr. Wilton Marion Krogman was one of the major founders of physical and forensic anthropology in the United States. His extraordinary career spanned nearly six decades, and he was universally admired and respected for his scholarship, teaching, research, wit, and humanity. While studies based on human skeletal remains have long been used to assist the medicolegal system, the late Dr. Krogman can be credited with uniting these areas into the discipline of forensic anthropology. His "Guide to the Identification of Human Skeletal Material" (1939) in the F.B.I. Law Enforcement Bulletin became the foundation of this discipline; his monumental book The Human Skeleton in Forensic Medicine (updated with the author in 1986) solidified its establishment. The purpose of this paper is to pay tribute to this great man and outline his influence on the development and advancement of forensic anthropology.  相似文献   
157.
Is medical care different? Old questions, new answers   总被引:3,自引:0,他引:3  
This paper examines whether changes in medical markets may be making them more like other markets. The emergence of HMOs and other managed care systems appears to have increased the consumer's potential ability to make better comparative judgments about the price and quality of medical care, and also seems to have made medical care more like other goods. However, the evidence that medical care is a "reputation good" suggests that it is, in this respect, different from other goods. Finally, the social concerns about medical care use necessarily make medical care different.  相似文献   
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This Article analyzes the development and complexities of the antitrust state action doctrine and the Local Government Antitrust Act as these doctrines apply to both "municipalities" and private entities. The restructuring of a public hospital is used as a model to facilitate the antitrust analysis. The restructuring model, which typically involves the leasing of a hospital facility by a public entity to a private nonprofit corporation, offers the unique opportunity to compare the different standards employed under the state action doctrine and the Local Government Antitrust Act. As a practical matter, the Article provides a framework for a public hospital to evaluate the impact of corporate restructuring on its antitrust liability exposure and to develop strategies to minimize antitrust risks.  相似文献   
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