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51.
Foot-and-mouth disease (FMD) is a viral disease of domesticated and wild cloven-hoofed animals. FMD virus is known to spread by direct contact between infected and susceptible animals, by animal products such as meat and milk, by the airborne route, and mechanical transfer on people, wild animals, birds, and by vehicles. During the outbreak of 2001 in the Netherlands, milk from dairy cattle was illegally discharged into the sewerage as a consequence of transport prohibition. This may lead to contaminated discharges of biologically treated and raw sewage in surface water that is given to cattle to drink. The objective of the present study was to assess the probability of infecting dairy cows that were drinking FMD virus contaminated surface water due to illegal discharges of contaminated milk. So, the following data were collected from literature: FMD virus inactivation in aqueous environments, FMD virus concentrations in milk, dilution in sewage water, virus removal by sewage treatment, dilution in surface water, water consumption of cows, size of a herd in a meadow, and dose-response data for ingested FMD virus by cattle. In the case of 1.6 x 10(2) FMD virus per milliliter in milk and discharge of treated sewage in surface water, the probability of infecting a herd of cows was estimated to be 3.3 x 10(-7) to 8.5 x 10(-5), dependent on dilution in the receiving surface water. In the case of discharge of raw sewage, all probabilities of infection were 100 times higher. In the case of little dilution in small rivers, the high level of 8.5 x 10(-3) is reached. For 10(4) times higher FMD virus concentrations in milk, the probabilities of infecting a herd of cows are high in the case of discharge of treated sewage (3.3 x 10(-3) to 5.7 x 10(-1)) and very high in the case of discharge of raw sewage (0.28-1.0). It can be concluded that illegal and uncontrolled discharges of contaminated milk into the sewerage system may lead to high risks to other cattle farms at 6-50 km distance of the location of discharge within one day. This clearly underlines current measures that prohibit such discharges, and also asks for strict control. This risk assessment clearly demonstrated the potential significance of FMD virus transmission via water, and the results will be useful on an international scale, and could also serve as a basis for other FMD risk-assessment models.  相似文献   
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The Analysis of Verbal Behavior - The behavioral effects of environmental events can be classified as evocative when we refer to an immediate but momentary change in behavior, and as...  相似文献   
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This essay is a response to questions raised by my review of a book by Uta Gerhardt called Talcott Parsons on National Socialism.In short, I found many issues unresolved in the Cold War years from 1946 to 1954 at Harvard University, especially the role of Talcott Parons and Clyde Kluckhohn in allegedly bringing Nazi collaborators to the United States. I have tried to address these controversial issues in this response.  相似文献   
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This paper examines the concept of union instrumentality in light of theoretical literature and contemporary trends in union political activity. A broad concept of union instrumentality, including a place for the concept of union political instrumentality (e.g., union influence on general elections or legislation), is suggested. The practical importance and applicability of the political instrumentality concept is demonstrated in empirical models of nonunion worker voting intent in union representation elections. As predicted, workers perceiving higher levels of union political instrumentality are significantly more likely than others to indicate a pro-union voting intent. Given the importance of political versus economic activity as a defining characteristic of labor movements and given recent increases in political activity by U.S. unions, these results have significant implications for the way we think about U.S. unions and for future union organizing and political activities. The author wishes to acknowledge helpful comments on an earlier version of this paper from Mario F. Boganno, Frederic C. Champlin III, William N. Cooke, James A. Craft, John T. Delaney, Richard B. Freeman, Daniel G. Gallagher, Cynthia L. Gramm, Charles R. Greer, Wallace E. Hendricks, Marick F. Masters, Lee P. Stepina, and William A. Wines. An earlier version of this paper was presented at the Thirty-Eighth Annual Meeting of the Industrial Relations Research Association, New York, NY, December 1985.  相似文献   
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This paper presents the results of an ecological analysis of the relationship between infant mortality and economic status in a metropolitan aggregate comprised of seven of the larger cities in Ohio during the three years centering on the 1990 census. Using a summary income score derived for the census tract of mother's usual residence, the census tracts in the seven metropolitan centers were divided into broad income groupings and three-year average infant mortality rates were computed for each area, by age, sex, race, and selected causes of death. The most important conclusion to be drawn from the data is that in spite of some remarkable declines in overall levels of infant mortality during the past few decades, there continues to be a very clear and pronounced inverse association between income status and infant mortality. The general inverse association is observed for both sexes, for whites and nonwhites, and for all major causes of infant death. At the same time, the data reveal notable differences in the magnitude of the relationship by sex, and especially by age at death, race, and cause of death. Explanations of these differences are suggested, and a conclusion notes some of the difficulties encountered in developing programs aimed at closing the infant mortality gap between the richest and poorest segments of the society.This is an expanded version of a paper presented at the annual meetings of the Eastern Sociological Society in Baltimore, Maryland (March 17–20, 1994).  相似文献   
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