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41.
Within the context of transboundary disputes, this paper seeks to determine which liability concept, negligence or strict liability, performs better when assets are secure against foreign claims for transboundary damages. Our results indicate that, if assets are hidden from foreign claims, strict liability will not implement the socially optimal outcome, but neither will negligence. However, even though the socially optimal outcome is not always achieved, strict liability weakly dominates negligence. These results suggest that the harmonization of statues that deal with transboundary pollution should be based on strict liability not negligence. JEL classification K32 · Q5 Smith and Eckert both thank SSHRC of Canada for financial assistance. We thank two referees for valuable comments that greatly improved the paper and Matt Smith for his research assistance. All remaining errors are our responsibility.  相似文献   
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The fingernail ridge patterns of a pair of identical twins were compared to each other, their parents, and an unrelated subject. The patterns of the twins' nails showed regions of strong similarity but were distinguishable from one another. Fewer similarities were found when comparing the nails to those of the parents and the unrelated control. The twins were shown to be monozygotic by means of DNA profiling. This therefore represents the first demonstration of unique fingernail ridge patterns in subjects shown conclusively to be identical twins. When the fingernail ridge patterns were examined with a scanning electron microscope, the backscattered electron (BEI) images were found to have superior contrast when compared to the secondary electron (SEI) images.  相似文献   
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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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This paper finds that the relatively favorable standing of Ronald Reagan in the preelection polls helped to generate a bandwagon effect in the 1980 presidential election. The models tested here suggest that this effect was most pronounced among voters who had the weakest prior political opinions and hence were most susceptible to suggestion through the media. While the bandwagon effect that is generated is modest, after controlling for an array of other political biases, it is substantial enough to warrant further attention as the dissemination of poll results becomes an increasingly attractive news event.  相似文献   
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