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J. Röttger J. Klostermeyer P. Czechowsky R. Rüster G. Schmidt 《Die Naturwissenschaften》1978,65(6):285-296
Problems in atmospheric dynamics, in particular in micro- and mesoscale processes, which can be solved by radar investigations, are summarized. The method of atmospheric radar experiments is described. Some relevant results obtained with the new SOUSY-VHF-Radar are presented, including observations of a warm-front passage, of layered structures, and of vertical and horizontal velocities in the troposphere. A power profile of radar echoes from heights up to the stratosphere proves that the SOUSY-VHF-Radar in its final operating state will be able to investigate structures and dynamics in the mesosphere too. 相似文献
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Isozymes and general protein patterns as taxonomic markers in the taxon Nephtyidae (Annelida Polychaeta) 总被引:2,自引:0,他引:2
Seven Nephtys species and one species of the genus Aglaophamus (collected from different European tidal and subtidal locations between 1989 and 1991) were compared with respect to six isozyme systems (-amylase, esterase, hexokinase, malate dehydrogenase, malic enzyme, phosphoglucoseisomerase) as well as with respect to general protein patterns with non-specific staining. The proteins were obtained from the tissue (proboscis, individual segments) of single individuals, the species of which had previously been accurately determined, and were separated by isoelectric focusing (IEF) in polyacrylamide gels. The enzymes were identified by their specific catalytic activities, and the general proteins were visualized by silver staining. All the isozymes proved to be monomorphic within each of the various polychaete populations. With a single exception, it was impossible to distinguish geographically separated populations of the same species, because the band patterns were completely consistent within the species. The individual enzymes varied in their suitability for species differentiation. Only with respect to esterase and -amylase could all species be distinguished; the other enzymes studied were identical in morphologically similar species. In contrast, each species could be identified by its general protein pattern, although some species differed from others in the position of a few bands only. Individuals of N. hombergii, N. caeca and N. cirrosa with abnormally shaped parapodia, as well as juvenile nephtyids, could be unequivocally assigned to their respective species by IEF. Only in the case of N. longosetosa were two morphological variants found to differ in their electrophoretic characteristics; one of them is interpreted as a new species, not previously described. 相似文献