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Quadratic pieces of fleece measuring 16 mm2 were soaked with 10 different blood-samples in the dilution steps of 1:1, 1:10, 1:100, 1:1000, respectively, and were tested in blood group typing and identification tests of forensic serology. The above spezified dilutions correspond with 5 microliters, 0.5 microliter, 0.05 microliter and 0.005 microliter of blood, respectively. The detection limit of the microspectrometric test for blood was the dilution 1:10, of the porphyrine test a dilution above 1:100, whereas the preliminary test for blood (peroxidase) succeeded always up to a dilution of 1:1000 and the species determination by the radial immunodiffusion test in agar gels succeeded in most cases op to a dilution of 1:1000. The detection limit of the anti-human globulin inhibition test was between the dilution steps 1:10 and 1:100 when non-titrated and undiluted anti-human globulin serum was used. Gc- and ABO-grouping were possible up to a dilution of 1:100 and were thus the most sensitive grouping systems. Phenotyping of the enzyme-systems and the Gm/Km-system usually required stains with considerably higher blood concentrations i.e. stains of undiluted blood. 相似文献
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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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Recently, various authors have examined the relationship between growth in government size and total economic growth. In each case, the authors permitted only a monotonic relationship. This paper examines the issue of a non-linear relationship between growth in government and overall growth in the economy.Government contributes to total economic output in various ways. The provision of Pigovian public goods enhances the productivity of the private sector inputs increasing total output. However, the public decision-making process can result in an inefficient quantity of public goods. The likelihood of this outcome increases with the size of government. Further negative effects are created by the revenue raising and spending mechanisms of government, and the increasing diversion of resources into unproductive rent-seeking activities. The magnitude of these effects is likely to increase with the relative size of government. 相似文献