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131.
The application of stable hydrogen isotope (deltaD) techniques has swiftly advanced our understanding of animal movements, but this progression is dominated by studies of birds and relatively long-distance, north-south migrants. This dominance reflects the challenge of incorporating multiple sources of error into geographic assignments and the nature of spatially explicit deltaD models, which possess greater latitudinal than longitudinal resolution. However, recent progress in likelihood-based assignments that incorporate multiple sources of isotopic error and Bayesian approaches that include additional sources of information may advance finer-scale understanding of animal movements. We develop a stable-isotope method for determining probable origins of bats within hibernacula and show that this method produces spatially explicit, continuous assignments with regional resolution. We outline how these assignments can be used to infer hibernacula connectivity, an application that could inform spatial modeling of white-nose syndrome. Additionally, estimates of seasonal and annual flight distances for many cave-dwelling bat species can be derived from this approach. We also discuss how this application can be used in general to provide insights into variable migratory and foraging strategies within bat populations. 相似文献
132.
Rolf D. Schmid 《Die Naturwissenschaften》1987,74(6):267-274
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
133.
134.
Herbert G. Stangland Rolf T. Skrinde 《Journal of the American Water Resources Association》1975,11(4):783-795
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
135.
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
136.
Vladimir Kucera Johan Tidblad Katerina Kreislova Dagmar Knotkova Markus Faller Daniel Reiss Rolf Snethlage Tim Yates Jan Henriksen Manfred Schreiner Michael Melcher Martin Ferm Roger-Alexandre Lefèvre Joanna Kobus 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):249-258
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
137.
Rolf Meissner 《Die Naturwissenschaften》1981,68(9):437-442
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
138.
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
139.
140.
Hans Pohl Benjamin Wipfler David Grimaldi Felix Beckmann Rolf G. Beutel 《Die Naturwissenschaften》2010,97(9):855-859
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