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Ninety-eight laboratories in 16 countries were surveyed in 1979 to determine the uniformity of methods for the assay of human viruses in BGM cells. None of the 58 responding laboratories applied identical methodology. A number of these practices were sufficiently different to assure a significant variance in liter with the assay of standardized virus samples. The results of this survey indicate a definite need for implementing uniform cell culture practices for the enumeration and identification of viruses in the environment. 相似文献
404.
Daniel Stiles 《The Environmentalist》1984,4(2):93-96
Summary Following the severe droughts in the Sahel and Ethiopia in the late 1960s and early 1970s, which focused the world’s attention
on drought and desertification, the United Nations system organized and held the UN Conference on Desertification (UNCOD)
in Nairobi in 1977. The principal outcome of the Conference was a Plan of Action to Combat Desertification (PACD), containing
28 major recommendations. The follow-up and coordination of implementation of the PACD was entrusted to UNEP, which created
a Desertification Branch in 1978 to undertake the task.
Desertification Branch UNEP 相似文献
405.
Thomas A. O'Neil Robert J. Steidl W. Daniel Edge Blair Csuti 《Conservation biology》1995,9(6):1482-1491
Determining which vegetation types organisms perceive similarly and classifying these types into groups that function as similar habitats are necessary steps toward expanding the focus of conservation strategies from single species to ecosystems. Therefore, the methods used to determine these habitat classifications are crucial to the successful design and implementation of these conservation strategies. Typically, this process has been accomplished through best professional judgement. We used quantitative techniques to group vegetation types into habitats based on the occurrence of breeding wildlife species ( n = 420) in Oregon. After calculating faunal similarities among all regional vegetation types ( n = 130), we used cluster analysis to group vegetation types into wildlife habitats. We classified the original 130 vegetation types into 30 wildlife habitat types that we believe function similarly. We tested this classification to assess whether vegetation types could be correctly classified into habitat types based on wildlife species composition. Discriminant analysis correctly classified 95% of the vegetation types into their wildlife habitat types, strengthening our confidence in this approach. This approach for classifying habitat types allows consistent development of conservation strategies at coarse resolutions and aids in identifying vegetation types where additional biodiversity surveys are needed. Finally, this approach can be refined continuously as the precision of vegetation mapping and our understanding of organism-habitat associations improve. 相似文献
406.
This article explores an increasingly salient employment issue, namely, underemployment of recent college graduates. Using a sample of 283 recent business college graduates, the paper examines the consequences of underemployment on individuals' attitudes towards their jobs, their careers, and their lives in general. It explores, as well, how recent college graduates cope with underemployment and the impact of those coping strategies on individuals' psychological well-being. The paper concludes with directions for future research on underemployment among recent graduates in terms of theory development, research methodology, and public policy formulation. 相似文献
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I. Baldini M. Lo Giudice P. De Grossi G. Vestri R. Muratori 《Chemistry and Ecology》1986,2(4):301-311
Physico-chemical, microbiological, ichthyotoxicological conditions and microalgae of Varenna stream were studied in samples taken in 12 collecting stations. The data reported indicate a marked deterioration proceeding downstream e.g. an increase of bacterial population, concentration of suspended solids, COD and variations in the composition and abundance of phytoplankton and periphyton. 相似文献
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