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131.
By combining information about Biotechnology in Japan manually retrieved from Chemical Abstracts (Biochemical Section) with information obtained from Japanese sources, Japanese scientific meetings and from appropriate magazines such as Nikkei Biotech, a basis was formed for a better understanding of the status and perspectives of this field. Through the development of a "biotechnology abstract analyzer" program, these data were further refined and prepared for continuous up-date. Thus, assessment of changes in institute structures and trends in research goals became possible. It is evident that similar procedures can be applied to any field of science in other geographic areas.  相似文献   
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ABSTRACT: Land development projects that are presumed to have regional impact according to the Florida Land and Water Management Act of 1972 are forced to minimize adverse environmental impact through a detailed procedure called Application for Development Approval (ADA). In Southeast Florida, as part of this review process, the water-supply and flooding conflicts must be resolved with the regional water management agency, Central and South Florida Flood Control District (FCD). This paper discusses the efforts to resolve these two conflicts for a large proposed residential development in Broward County, Florida. The project, as envisioned by Leadership Housing, Inc., places 25,000 dwelling units on the 3,960-acre site. The project is located in a flood prone area of the Hillsboro Canal Basin and is at the northwest edge of the Biscayne Aquifer. Significant land modification is required to flood-proof the project. The water-supply conflict was resolved only when the FCD was assured that the ultimate water demand for the project was balanced by the natural recharge to the site. Significant water-resources studies were required to produce these conflict resolutions.  相似文献   
134.
Angiogenesis factors in gliomas: a new key to tumour therapy?   总被引:16,自引:0,他引:16  
Angiogenesis, the formation of new blood vessels, is required for the growth and expansion of tumours. Gliomas, the most common brain tumours, are particularly highly vascularized and, therefore, serve as a model to elucidate the process of tumour angiogenesis and to investigate new anti-angiogenic therapies. This review describes the role of angiogenic factors in glioma angiogenesis and new strategies to inhibit glioma growth by application of anti-angiogenic substances. We focus on vascular endothelial growth factor (VEGF), but also examine the role of angiopoietin and pleiotropic factors such as platelet-derived growth factor (PDGF), pleiotrophin and transforming growth factor- (TFG-). Strategies to inhibit glioma growth by reducing the action of angiogenic factors, by the application of anti-angiogenic substances such as angiostatin or endostatin, or inactivation of endothelial cells, are discussed. These new anti-angiogenic therapies appear to have a high potential not only for the treatment of gliomas, but also of other tumours.  相似文献   
135.
A “multi-pollutant exposure programme” reflecting the new pollution situation where SO2 is no longer the dominating pollutant has been performed by the International Co-operative Programme on Effects on Materials, including Historic and Cultural Monuments (ICP Materials) within the activities of the Convention on Long-range Transboundary Air Pollution. The main results obtained in the period 1997–2003 are summarised. Dose-response functions are presented for carbon steel, zinc, copper, bronze and limestone. Parameters involved in the functions include besides SO2 and pH, which were included in the previously developed functions from ICP Materials, also the effect of particulate matter and HNO3.  相似文献   
136.
Geothermal energy, produced by the decay of long-lived radioactive elements in the earth's crust and inherited by the earth's formation, appears in a concentrated and exploitable form at several places in the upper 1 to 3 km of the earth's crust. The hotter the rock-water system is, the more use can be made of generation of electricity. District heating, on the other hand, can be performed by rather moderate temperatures of circulating waters in permeable sediments, a situation which is often encountered in the large sediment basins of West and Central Europe.  相似文献   
137.
A mathematical model of radionuclide kinetics in a laboratory microcosm was built by systems identification techniques. Insight into the functioning of the system was obtained from analysis of the model. Methods employed have allowed movements of radioisotopes not directly observable in the experimental system to be distinguished. Results are generalized to whole ecosystems.  相似文献   
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Fossilization in amber is unique in preserving specimens with microscopic fidelity; however, arthropod inclusions are rarely examined beyond the exoskeleton as this requires destructive sampling when traditional techniques are used. We report the first complete, digital 3D, non-destructive reconstruction of the anatomy of an insect fossil, a specimen of †Mengea tertiaria embedded in a 42-Ma Baltic amber. This was made possible using Synchrotron μ-CT. The species belongs to the stem group of the phylogenetically enigmatic and extremely specialized Strepsiptera. Most internal structures of the fossil are preserved, but small parts of the lumen had decayed due to incomplete infiltration of the resin. Data on internal organs provided additional information for resolving phylogenetic relationships. A sister group relationship between †Mengea and all extant lineages of the group was confirmed with characters previously not accessible. The newly gained information also yielded some insights in the biology of †Mengea and the early evolutionary history of Strepsiptera. The technique has a tremendous potential for a more accurate interpretation of diverse fossil arthropods preserved in ambers from 130 Ma to the present.  相似文献   
140.
Regional Environmental Change - Planning for the future requires a detailed understanding of how climate change affects a wide range of systems at spatial scales that are relevant to humans....  相似文献   
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