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11.
12.
O. B. Denisov N. Yu. Orlov S. Yu. Gus’kov V. B. Rozanov N. V. Zmitrenko A. P. Mikhailov 《Plasma Physics Reports》2005,31(8):684-689
A method for calculating and optimizing the composition of materials for soft X-ray sources used in research on inertial confinement fusion is described. For a target-converter, a material composition is determined with which the conversion of laser light into X radiation is highly efficient. A comparative analysis is carried out of the efficiencies of generation of soft X-ray emission in the plasmas of some composite materials of thin conductors (wires) used as loads in X-and Z-pinches. Numerical calculations of the optical plasma properties are reported whose results make it possible to judge the emissivity of plasmas of different materials. The results obtained are compared to the data from other studies. 相似文献
13.
N. K. Berezhetskaya S. I. Gritsinin V. A. Kop’ev I. A. Kossyi D. van Wie 《Plasma Physics Reports》2005,31(10):886-890
The generation of long-lived microplasmoids is observed during the irradiation of a metal-dielectric surface with a high-power microwave beam in a chemically active gas mixture (H2 + O2; CH4 + O2). The lifetime of these plasmoids substantially exceeds the characteristic recombination and cooling times of plasmoids arising at the target surface in a chemically inactive medium. 相似文献
14.
Yu. V. Gamalei 《Russian Journal of Developmental Biology》2005,36(3):129-144
Phylogenetic and ontogenetic relationships between the plastids, cell endoplasmic reticulum, and plant transport communication have been reviewed. The initiating role of plastids (endosymbionts) in the origin of endoplasmic reticulum (buffer zone of endosymbiogenesis) has been shown, as well as a similar role of endoplasmic reticulum in the development of transport communication of xylem and phloem. Plastids, sugars and transport system for their distribution can be interpreted as leading sections in the mechanism of developmental control: gene expression of nuclear genome and genome of organelles, cell and tissue differentiation, and plant morphogenesis. The conflict between the bulk of plant genome and low percentage of its realization is explained as a result of limitation of the nuclear genome realization by plastid genome. The concept of development as applied to plant ontogenesis has been critically analyzed. The possibilities of the concept correction by with the help of symbiogenetic hypothesis are discussed.__________Translated from Ontogenez, Vol. 36, No. 3, 2005, pp. 165–181.Original Russian Text Copyright © 2005 by Gamalei. 相似文献
15.
L. K. Ignatova N. S. Novichkova V. A. Mudrik V. Yu. Lyubimov B. N. Ivanov A. K. Romanova 《Russian Journal of Plant Physiology》2005,52(2):158-164
The effects of CO2 concentration (C
a) on growth, photosynthesis, and the activity of enzymes associated with the translocation and assimilation of CO2 were studied in sugar beet (Beta vulgaris L. subsp. saccharifera, cv. Ramonskaya) plants. The plants were grown in controlled-climate chamber to the stage of 3–4 leaves and then used in experiments. Experimental plants were exposed in boxes to doubled C
a (700 µl/l, 2C plants), whereas control plants were kept in a chamber with ambient atmosphere (350 µl/l, 1C plants). As compared with 1C plants, in 3 and 8 days, the leaf area of 2C plants increased by 14 and 26%, respectively. The rate of their photosynthesis (P
n) measured in 3, 6, and 8 days increased by 85, 47, and 52%, respectively, whereas in normal air, the values of P
n in 2C plants were by 12, 19, and 15% lower than in 1C plants. After 8-day growth, the content of soluble carbohydrates in the leaves of 2C plants attained 7.2%, being by 80% greater than in 1C plants; the content of starch did not exceed 3%. The total content of chlorophylls a and b in the leaves of 2C plants was by 14% greater than in 1C plants, but their ratio was essentially the same. The level of protein in 2C plants was by 13.4% lower than in 1C plants. The activity and content of Rubisco in 1C and 2C plants were similar. As compared with 1C plants, in 2C plants the activity of soluble carbonic anhydrase (sCA) was lower by 34% in 3 days and by 18% in 8 days; the activity of carbonic anhydrase of membrane preparations (mCA), was lower by 24 and 77%, respectively. Catalase activity in 2C plants became by 8% lower than in 1C plants only after 8 days. A reduction in the photosynthetic ability of 2C plants in ambient atmosphere, a decrease in activity of sCA and, especially, of mCA observed together with invariable activity and content of Rubisco in the leaf extracts are interpreted as early symptoms of acclimation of young plants of sugar beet to elevated CO2.Translated from Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 184–190.Original Russian Text Copyright © 2005 by Ignatova, Novichkova, Mudrik, Lyubimov, Ivanov, Romanova.This revised version was published online in April 2005 with a corrected cover date. 相似文献
16.
A method of in silico search for specific repetitive DNA sequences related to the synaptonemal complex (meiDNA) in mammalian genomes was developed. A study of the distribution of these repeats over chromosomes revealed their scarcity on the Y chromosome and a decrease in recombination frequency in regions enriched in meiDNA. The results are discussed in context of the model of the looplike meiotic chromosome organization during the formation of the synaptonemal complex.__________Translated from Genetika, Vol. 41, No. 5, 2005, pp. 697–701.Original Russian Text Copyright © 2005 by Grishaeva, Dadashev, Bogdanov. 相似文献
17.
In April 2004, an expedition to the Caspian Sea discovered the species in the Middle Caspian not previously described in this sea. These species preliminary identified as Oithona similis Claus 1963, Sagitta setosa Muller 1847, and Calanus euxinus (Hulsemann) are the main representatives of edible plankton of the Black Sea; most likely they were introduced into the Caspian Sea with ballast waters of ships passing through the Volga-Don Canal. At present, it is difficult to say if these species will be established in the Caspian Sea; if so, they will clearly become a valuable food resource for planktophagous fish in the Caspian Sea. In addition, we discovered two diatom species typical for the Black Sea phytoplankton, Pseudo-nitzschia seriata (Cleve) H. Peragallo and M. Peragallo and Cerataulina pelagica (Cleve) Hendey which invaded the Caspian Sea in recent years. Pseudo-nitzschia seriata synthesizes a toxin (domoic acid) and can become harmful for the basin in the case of mass bloom. We discuss the problem of spontaneous invasion of alien species from the Black Sea and their effect on the Caspian ecosystem in the context of these findings.Translated from Izvestiya Akademii Nauk, Seriya Biologicheskaya, No. 1, 2005, pp. 78–87.Original Russian Text Copyright © 2005 by Shiganova, Musaeva, Pautova, Bulgakova. 相似文献
18.
L. N. Maslov A. Yu. Lishmanov E. V. Budankova D. L. Stakheev N. V. Solenkova E. I. Barzakh P. R. Oeltgen G. J. Gross W. S. Chang 《Biology Bulletin》2005,32(4):375-380
Preliminary selective blockade of µ, δ1, δ2, κ1, and κ2 opioid receptors proved to have no effect on the incidence of ventricular arrhythmias during a 10-min coronary occlusion and subsequent reperfusion in ket-amine-anesthetized rats. We propose that the endogenous opioid system has no considerable role in regulation of heart resistance to the arrhythmogenic effect of short-term local ischemia and subsequent reperfusion.__________Translated from Izvestiya Akademii Nauk, Seriya Biologicheskaya, No. 4, 2005, pp. 453–459.Original Russian Text Copyright © 2005 by Maslov, Lishmanov, Budankova, Stakheev, Solenkova, Barzakh, Oeltgen, Gross, Chang. 相似文献
19.
20.
Piero Genovesi 《Biological invasions》2005,7(1):127-133
Eradication of alien species is a key conservation tool to mitigate the impacts caused by biologic invasions. The aim of the
present paper is to review the eradications successfully completed in Europe and to discuss the main limits to a wider application
of this management option in the region. On the basis of the available literature – including conference proceedings, national
reports to the Bern Convention, etc. – a total of 37 eradication programmes have been recorded. Thirty-three eradications
were carried out on islands and four on the mainland. The rat (Rattus spp.) has been the most common target (n = 25, 67%), followed by the rabbit (n = 4). In many cases, these eradications determined a significant recovery of native biodiversity. Differently to other regions
of the world, no eradications of alien invertebrates and marine organisms have been recorded; regarding invasive alien plants,
it appears that only some very localized removals have been completed so far in Europe. The limited number of eradications
carried out in Europe so far is probably due to the limited awareness of the public and the decision makers, the inadequacy
of the legal framework, and the scarcity of resources. Synthetic guidelines for improving the ability of European states to
respond to aliens incursions are presented.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献