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941.
942.
A major diesel emissions research program has been initiated by the U.S. Environmental Protection Agency to assess the human health risk associated with increased use of diesel automobiles. This program is intended to establish the mutagenic and carcinogenic potency of complex organics associated with diesel particles as well as comparative particle-bound organics from other environmental emissions for which human epidemiological data are available. The mobile source samples selected for this study were collected from a heavy-duty diesel engine, a series of light-duty diesel passenger cars, and a gasoline catalyst automobile. The comparative source samples incorporated into the study were cigarette smoke condensate, coke oven emissions, roofing tar emissions, and benzo(a)pyrene. The samples were tested using three mutagenic assays and four carcinogenic assays as prescribed by a test matrix. This report describes the study design, particle generation, and sample collection and preparation. A brief summary of the bioassays is also included.  相似文献   
943.
Summary This paper focuses on the emphasis placed on environmental considerations and values in the context of environmental in-service training programs for governmental personnel in England, Austria, the Federal Republic of Germany, and the Netherlands. The paper is generally based on field research conducted in Europe during August 1979; issues were identified and comparisons were made with training programs in the United States. The major issues considered include: (1) early versus later emphasis, (2) resistance, (3) specialists and techno-scientific emphasis, (4) technique orientations, (5) lack of environmental administrative training, and (6) innovations.Despite various contrasts between European and United States environmental in-service training programs, there are some similarities. Many of these similarities center around a lack of emphasis on environmental training per se as well as on a lack of emphasis on environmental considerations and values because of various constraints, perceptions, and orientations. As developed nations with advanced governmental-technological systems in environmental affairs, their training programs are highly oriented toward these systems, and there is a lack of attention devoted to environmental aspects per se. The environmental titles and responsibilities do not automatically insure the incorporation of environmental considerations and values into the policy-making process with obvious training needs.European governments may adhere to a more legalistic, formal, and structured approach with less discretion available. But specialist and administrative personnel, as in the United States, are intimately involved in value judgments and decision-making in environmental affairs. Because of this, training programs have a special responsibility to educate personnel about environmental considerations and values to insure that the environmental public interest is adequately presented in the decision-making process, i.e., that they develop environmental competencies as well as governmental and technological ones on an interface basis.Dr Daniel H. Henning is Professor of Political Science and Distinguished Scholar Professor at Eastern Montana College. His interest and expertise is in the field of environmental training for government officials.  相似文献   
944.
The use of spectral analysis to elucidate the cyclic behavior in time series generated by a forest stand growth simulation model is discussed. A stand-level simulator, FORET, for an Appalachian deciduous forest is described. An estimate of the power spectral density of the total biomass time series is calculated. The power spectral density estimate indicates a dominant cyclic behavior with a period of about 200 years. In addition the spectral density is approximately bandlimited. This characteristic makes possible the application of the sampling theorem for analysis of sampling rates.  相似文献   
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