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James D. Goldberg MD Frank A. Chervenak Robert A. Lipman Richard L. Berkowitz 《黑龙江环境通报》1986,6(1):45-49
Arthrogryposis Multiplex Congenita (AMC) was suspected on ultrasound examination of a fetus at 30·5 weeks of gestation. The criteria for establishing this prenatal diagnosis as well as the importance of establishing the diagnosis at any gestational age are discussed. The diagnosis of AMC was confirmed at birth in this case. 相似文献
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Frank L. Parker 《Environment international》1980,3(3):205-211
The difficulties in resolving water resource policy questions are analogous in many ways to the difficulties in resolving energy policy questions — technical, legal, institutional and social. Federal involvement in water resources began in 1809 and continues to the present time. The most recent comprehensive study was the Second National Water Assessment by the U.S. Water Resources Council in 1979. Conclusions reached were that water quality and quantity and surface and ground water are artificial distinctions, that water policies should reflect national needs and priorities, that flood control must be accelerated and drinking water quality protected and that more decisions should be made at a local level while integrated into national planning and development. Though the study disaggregated the U.S. into 106 subregions, its projections of a single future rather than a range of futures gives an erroneous sense of predictability to the work. To help resolve the major problems, inadequate supply and contamination and flooding and erosion, ultrasophisticated mathematical models are widely utilized without sufficient verification. A more tractable approach for policy studies would be to use simplified semi-empirical models rather than first principle models. Possibly more important, policy resolution awaits social value resolution which means that the policies adopted must be flexible, incremental, and non-divisive. 相似文献
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Amit Kumar Srivastava Thomas Gaiser Frank Ewert 《Mitigation and Adaptation Strategies for Global Change》2016,21(6):955-968
Globally, yam (Dioscorea spp.) is the fifth most important root crop after sweet potatoes (Ipomoea batatas L.) and the second most important crop in Africa in terms of production after cassava (Manihot esculenta L.) and has long been vital to food security in sub-Saharan Africa (SSA). Climate change is expected to have its most severe impact on crops in food insecure regions, yet very little is known about impact of climate change on yam productivity. Therefore, we try estimating the effect of climate change on the yam (variety: Florido) yield and evaluating different adaptation strategies to mitigate its effect. Three regional climate models REgional MOdel (REMO), Swedish Meteorological and Hydrological Institute Regional Climate Model (SMHIRCA), and Hadley Regional Model (HADRM3P) were coupled to a crop growth simulation model namely Environmental Policy Integrated Climate (EPIC) version 3060 to simulate current and future yam yields in the Upper Ouémé basin (Benin Republic). For the future, substantial yield decreases were estimated varying according to the climate scenario. We explored the advantages of specific adaptation strategies suggesting that changing sowing date may be ineffective in counteracting adverse climatic effects. Late maturing cultivars could be effective in offsetting the adverse impacts. Whereas, by coupling irrigation and fertilizer application with late maturing cultivars, highest increase in the yam productivity could be realized which accounted up to 49 % depending upon the projection of the scenarios analyzed. 相似文献