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161.
We use US county level data from 1970 to 1998 to explore the relationship between economic growth and government employment at three levels: federal, state and local. Increases in federal, state and local government employments are all negatively related to economic growth. We find no evidence that government is more efficient at lower levels. While we cannot separate out the productive and redistributive services of government, we document that the county-level income distribution became slightly more unequal from 1970 to 1998. We conclude that a release of government-employed labor inputs to the private sector would be growth-enhancing. 相似文献
162.
Jock W. Young 《Journal of International Wildlife Law & Policy》2013,16(3):253-275
Abstract Although there is evidence that some populations of large whales in the Southern Hemisphere have increased in recent years, differences in feeding behaviour and migration patterns largely precludes direct competition between these and coastal and pelagic fisheries in the South Pacific Ocean. In particular, many of the whales that spend at least part of their year in the South Pacific make feeding migrations in summer to Antarctic waters where some estimates put their food intake at 90% of annual consumption. Others, such as female sperm whales (Physeter macrocephalus), which do not migrate from tropical/subtropical South Pacific waters, feed at depths greater than that usually occupied by species that are the targets of commercial fisheries, such as the tunas (Thunmisspp.). Thus, even though consumption by whales is high, dietary overlap with commercially fished species is relatively low as much of their feeding is in waters that are not exploited by fisheries. However, there are a number of anecdotal reports that some smaller cetacean species, in particular killer and pilot whales, take fish from longlines set in the region, although more are lost to sharks. However, it should be noted that any assessment of interactions between whales and fisheries is limited by a lack of qualitative and quantitative data. Abundance estimates, particularly for some of the smaller species in the South Pacific region, are only order of magnitude estimates. Furthermore, knowledge of food chains (and their interactions) for many cetaceans in the South Pacific is sketchy making assessment of their impact on local fisheries‐difficult. 相似文献
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d-3-Methoxy-17-methylmorphinan (Dextromethorphan, DXM), which is a structural analog of morphine and codeine, has been widely used as a non-narcotic antitussive agent. It is a safe drug in therapeutic dose and does not produce analgesic effects, while its enantiomer, l-3-methoxy-17-methylmorphinan called levomethorphan (LXM) is a potent narcotic analgesic. DXM has been widely abused in Korea due to its hallucinogenic effect in large doses; therefore, the health authorities have regulated its use as a psychotropic agent since 2003. As its abuse has been serious, a possibility that DXM would be smuggled into Korea has also increased. Moreover, it has been suspected that there was the possibility of the adulteration or substitution of DXM with LXM due to their chemical similarities. Therefore, it was necessary for us to establish the enantiomeric separation of DXM and LXM. In this study, a liquid chromatographic method using a chiral column capable of separating stereoisomers of DXM as well as analyzing the major metabolites of DXM, 3-methoxymorphinan, 3-hydroxymorphinan, and 17-hydroxymethylmorphinan was developed. The validation of a method was studied through repeatability of retention times. Using this method, 32 confiscated DXM samples were analyzed to identify the enantiomers of DXM. As a result, DXM was detected in all samples and there was no evidence of the adulteration or substitution of DXM with LXM. Nevertheless, the stereochemical analysis of DXM and LXM is important not only to identify starting materials for illegal drug manufacture but also to understand the trends of abused drugs. 相似文献
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Garg U Althahabi R Amirahmadi V Brod M Blanchard C Young T 《Journal of forensic sciences》2004,49(2):388-391
Vitreous humor is a suitable specimen for postmortem clinical chemistry because the analytes remain relatively stable after death and they closely reflect blood levels immediately prior to death. The viscous nature of vitreous fluid, however, presents analytical problems including imprecision and inaccuracy. Various preanalytical treatments, such as boiling, high speed centrifugation, microfiltration and dilution have been used. These techniques are labor intensive and add to imprecision and inaccuracy. Because glycosaminoglycans contribute significantly to the viscosity of vitreous humor, we used hyaluronidase as a liquefying agent. We compared the results of analyses in 33 vitreous humor specimens after hyaluronidase treatment with the results after either no treatment or specimen dilution. Seventeen of the 33 specimens could not be analyzed without dilution. Even after dilution, several analytes still could not be measured. Hyaluronidase treatment negated the need for sample dilution and had no significant effect on the analyses. 相似文献
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