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21.
S. I. Tkachenko A. R. Mingaleev V. M. Romanova A. E. Ter-Oganes’yan T. A. Shelkovenko S. A. Pikuz 《Plasma Physics Reports》2009,35(9):734-753
Distribution of matter in the discharge channel formed upon a nanosecond electrical explosion of a single wire in air and
vacuum was studied experimentally. Simultaneous use of optical, UV, and X-ray diagnostics made it possible to distinguish
qualitatively different regions of the discharge channel, such as the current-carrying layers and the region occupied by a
weakly conducting cold plasma. Several series of experiments with 25-μm-diameter 12-mm-long wires made of different materials
were performed. The charging voltage and the current amplitude were varied in the ranges of U
0 = 10–20 kV and I
max ∼ 5–10 kA, respectively. Explosion regimes with a current pause and with and without current interruption, as well as with
wire preheating in air and vacuum, were studied. Shadow and schlieren images of the discharge channel were obtained using
optical probing at the second harmonic of a YAG: Nd+3 laser (λ = 0.532 μm, τ ∼ 10 ns). In the experiments carried out in vacuum, X-ray images of the discharge channel were also
obtained using an X-pinch as a point source of probing radiation and UV images were recorded using a four-frame MCP camera. 相似文献
22.
E. N. Medvedeva N. A. Neverova T. E. Fedorova V. A. Babkin E. S. Meteleva A. V. Dushkin T. G. Tolstikova M. V. Khvostov M. P. Dolgikh 《Russian Journal of Bioorganic Chemistry》2010,36(7):853-859
It has been found by gel-penetrating chromatography and quantitative 13C NMR spectroscopy that mechanochemical processing of arabinogalactan isolated from the wood of the Siberian larch changes
the molecular mass distribution, monosaccharide composition, and the degree of branching of its macromolecules. This is due
to the partial destruction of polysaccharide macromolecules and subsequent recombination of resulting fragments. The intensity
of these processes depends on the conditions of mechanochemical processing. Based on the data of IR and 13C NMR spectra, the conclusion has been drawn that no functionalization of arabinogalactan macromolecules occurs under these
conditions. The toxicopharmacological properties of mechanically processed arabinogalactan have been studied. Its acute toxicity
is >5000 mg/kg. 相似文献
23.
Lincoln D Stein 《Genome biology》2010,11(5):207
With DNA sequencing now getting cheaper more quickly than data storage or computation, the time may have come for genome informatics
to migrate to the cloud. 相似文献
24.
The precipitation of tobacco mosaic virus by sodium chondroitin sulfate in an aqueous solution was investigated kinetically by means of turbidimetry. The virus solution became turbid after the addition of chondroitin sulfate. A threshold concentration of chondroitin, 1.33 mg/ml, was required for virus precipitation, irrespective of the virus concentration. The precipitation resulted from a mutual spatial exclusion phenomenon, leading to the separation of the virus as a crystalline phase. The dimension of chondroitin sulfate calculated at the threshold concentration agreed well with that obtained by other methods. The initial slopes and the aggregation half-times of the virus aggregates depended on both chondroitin and virus concentrations and the former increased with the increase in concentration of each. Above the threshold concentration of chondroitin sulfate, tobacco mosaic virus aggregation was a rapid-aggregation process and ended within 100 sec. 相似文献
25.
Rice fields are an alternative habitat for waterbirds and provide food and shelter for many avian species, but there is a lack of information about how the use of rice fields translates into population level effects. The aim of this study was to test the relationship between the use of rice fields by European waterbirds and trends in their populations. We tested this relationship during the autumn migration season and during the breeding season. Based on counts conducted over the last 23 years in natural marshes and areas of rice fields in Doñana (SW Spain), an index of rice field use was constructed for 76 bird species, which was then compared to these species’ European population trends obtained from the literature. A positive relationship was found between waterbird population trends and the use of rice fields during autumn migration season. Our study suggests that changes in the Common Agriculture Policy in Europe leading to reductions in areas of rice cultivation may have important effects on waterbirds. The restoration of former marsh areas and the maintenance of rice cultivation would seem to be more environmentally friendly approaches than the use of these areas to grow alternative crops or solar farms. 相似文献
26.
27.
The linkage of the Phi, Pgd, Po2, S, H and halothane sensitivity loci was followed in a Belgian Landrace family, heterozygous for these systems over 6 generations. Recombination next to the S locus occurred mainly in pigs belonging to this particular family. From this investigation the position of the S locus is proved to be outwith the Phi-Pgd region, next to Phi . Therefore the gene sequence S - Phi - Hal -H- Po2 -Pgd is proposed. Higher recombination rates were observed in the female parental line of the multiheterozygous family when compared to the male parental line. Additional data from animals, unrelated to this strain, confirm the evidence of close linkage of the S system to the nearest marker loci. 相似文献
28.
29.
N. V. Ozolina E. V. Kolesnikova V. N. Nurminsky I. S. Nesterkina L. V. Dudareva L. I. Donskaya R. K. Salyaev 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2010,4(3):297-301
The changes in transport activity of tonoplast proton pumps under the influence of exogenous NO donator and modulation of
Ca2+ concentration jointly and separately were investigated at different stages of ontogenesis and under hyperosmotic stress.
The results suggest that both exogenous NO donator and Ca2+ ions can influence the activity of transport processes related to tonoplast and this influence is especially evident in the
period of growth and accumulation of metabolites. Under hyperosmotic stress, H+-pyrophosphatase plays a more important role than H+-ATPase: the activity of the former increases 2.3-fold compared to the control osmotic conditions, whereas the activity of
H+-ATPase is practically unchanged. H+-pyrophosphatase was more responsive to the presence of exogenous NO donator and to variations in Ca2+ concentration. The effects of exogenous NO donator on tonoplast proton pumps depended on the concentration of Ca2+, which apparently can mediate NO action. 相似文献