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171.
Summary The conventional economic accounting systems have not played an enlightening role in statistically revealing the actual damage to the environment. They can, however, be methodologically improved; and they must be complemented by assessments of the ecological costs of the production process.In this article statistical evidence is provided on the level and structure of environmental damage and protection expenditures in the Federal Republic of Germany,i.e. on the environmental damage itself and on the environmental protection investments by industry and government, the capital stock for environmental protection, the total costs of and expenditures for environmental protection.Dr Christian Leipert and Prof. Udo Simonis are both regular contributors toThe Environmentalist (see 1989, pp.171–183; 1990, pp.25–38). Prof. Simonis is Director of the International Institute for Environment and Society (Wissenschaftszentrum) and Dr Leipert a member of its research staff. 相似文献
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In accordance with observations by other groups direct CVS preparations reveal only a few mitoses, whereas semi-direct cultures (overnight incubation) give good results. By monitoring the BrdU uptake with an immunological method, a delay in the proliferation activity in native villi could be observed up to 7 h after biopsy. 相似文献
179.
A specimen of the horned dinosaur Psittacosaurus from the early Cretaceous of China is described in which the integument is extraordinarily well-preserved. Most unusual is the presence of long bristle-like structures on the proximal part of tail. We interpret these structures as cylindrical and possibly tubular epidermal structures that were anchored deeply in the skin. They might have been used in display behavior and especially if one assumes that they were colored, they may have had a signal function. At present, there is no convincing evidence which shows these structures to be homologous to the structurally different integumentary filaments of theropod dinosaurs. Independent of their homology, however, the discovery of bristle-like structures in Psittacosaurus is of great evolutionary significance since it shows that the integumentary covering of at least some dinosaurs was much more complex than has ever been previously imagined. 相似文献
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