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41.
The article discusses the probable role of many factors that determine the individual variety of the neurophysiological mechanisms that provide the opportunity to learn and use fluently two or more languages. The formation of the speech function is affected by both the general factors for bilinguals and monolinguals, as well as by the specific characteristic of bilingualism. General factors include genetic and environmental impacts explaining the diversity of individual options for the development of the morphofunctional organization of the speech function. Bilinguals, obviously, have an even wider variation of the central maintenance of speech ability, due to the combination of different conditions that influence the language environment, which include the age of second language acquisition, the language proficiency, the linguistic similarity of the languages, the method of their acquisition, intensity of use, and the area where each language is used. The influence of these factors can be mediated in different ways by the individual characteristics of the bilingual??s brain. Being exposed to two languages from the first days of life, the child uses for the development of speech skills the unique features of the brain that exist only at the initial stages of postnatal ontogenesis. At an older age, mastering a second language requires much more effort, when, in the course of maturation, the brain acquires new additional possibilities but permanently loses that special ??bonus?? that nature gives to a small child only in the first months of life. Large individual variability patterns of activation of the cortex during verbal activity in older bilinguals, compared with the younger ones, allows us to assume that the brain of the older bilingual mastering a new language is forced to manipulate a large number of backup mechanisms, and this is reflected in an increase in the variation of the cerebral processes responsible for speech functions. In addition, there is a serious reason to believe that learning a second language contributes to the expansion of the functional capabilities of the brain and creates the basis for successful cognitive activity.  相似文献   
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Charge-exchange recombination spectroscopy under ITER conditions is numerically simulated using the DINA code. The code allows one to calculate the attenuation of neutral beams in plasma, the intensity of atomic emission and emission from the ions produced by charge exchange with the neutral beam, and the intensity ratio between the emission related to charge exchange and the background continuum plasma emission. The cross sections for atom-ion interactions in plasma are calculated, and the excitation rates of spectral transitions in hydrogen-like impurity ions are determined. The measurement scheme and the main parameters of the spectrometer proposed for charge-exchange recombination diagnostics in ITER are described.  相似文献   
44.
K. A. Blagodatskikh  M. A. Evdokimova  Yu. V. Agapkina  A. G. Nikitin  A. N. Brovkin  A. A. Pushkov  E. G. Blagodatskikh  O. Yu. Kudryashova  V. S. Osmolovskaya  L. O. Minushkina  M. S. Kochkina  N. D. Selezneva  E. N. Dankovtseva  O. S. Chumakova  T. N. Baklanova  P. A. Talyzin  N. E. Reznichenko  O. P. Donetskaya  S. N. Tereshchenko  E. S. Krasil’nikova  N. A. Dzhaiani  E. V. Akatova  M. G. Glezer  A. S. Galyavich  V. B. Zakirova  N. A. Koziolova  I. V. Timofeeva  A. V. Yagoda  O. I. Boeva  L. I. Katel’nitskaya  E. V. Khorolets  S. V. Shlyk  E. G. Volkova  M. P. Margaryan  I. O. Guz’  V. O. Konstantinov  N. V. Timofeeva  B. A. Sidorenko  D. A. Zateishchikov  V. V. Nosikov 《Molecular Biology》2010,44(5):741-747
Association between the rates of poor outcomes in the patient cohort with acute coronary syndrome and polymorphisms G(?174)C in the IL6 gene and G(?1082)A in the IL10 gene were determined. In total, 1145 patients hospitalized for coronary artery disease to cardiological hospitals of Moscow, St. Petersburg, Kazan, Chelyabinsk, Perm, Stavropol, and Rostov-on-Don were examined. The mean observation period was 9.10 ± 5.03 months (maximal, 18 months). Analysis of the survival of the patients with acute coronary syndrome that carried allele A has demonstrated that the presence of IL10 gene polymorphism G(?1082)A is associated with more frequent poor outcomes as compared with GG genotype. The survival time to endpoint for the carriers of GA and AA genotypes was 11.68 ± 0.67 months versus 12.69 ± 0.65 months for the carriers of GG genotype in IL10 gene (χ2 = 4.13, p = 0.042). As for the IL6 gene polymorphism G(?174)C, survival rate analysis did not detect any significant association with the risk for poor outcome. However, joint analysis of these polymorphisms in both genes has demonstrated that characteristic of the patients with acute coronary syndrome that carry GG genotype of IL6 gene and GA and AA genotypes of IL10 is a higher rate of poor outcomes (time to endpoint, 11.01 ± 1.24 months) as compared with the carriers of IL6 gene CC and CG genotypes and IL10 gene GG genotype (time to endpoint, 13.28 ± 0.83 months (ξ2 = 10.23, p = 0.017). These data suggest that the genes IL6 and IL10, whose products are involved in the control of inflammatory response, play an important role by increasing the probability of poor outcomes in the patients with acute coronary syndrome.  相似文献   
45.
Similarity coefficients were quantified for the ecosystems of the West Siberian Plain on the basis of the air-dry masses of dominant and subdominant plant species in five life forms (mosses, lichens, grasses, dwarf shrubs, shrubs, and trees) indicated in the formation ranges of the phytogeographic map of the West Siberian Plain. The resultant matrix was studied with cluster analysis and two classifications were made: one averaged over the formation ranges and the other over groups of the formation ranges. Expected informativity of the proposed classifications expressed in explained variance was 11–16% higher than that of the vegetation-based division used in the original phytogeographic map.  相似文献   
46.
Results are presented from experiments on the implosion of wire arrays powered from 100-and 200-mm-diameter helical explosive magnetocumulative generators with explosive opening switches. The experiments were performed at load currents of up to 4 MA, the current rise time being 0.3–0.4 μs. The maximum soft X-ray yield of ~ 100 kJ was achieved at a pinch plasma temperature of 55 eV. A two-dimensional MHD code was developed to simulate the process of liner implosion and the generation of X-ray emission. The results of computer simulations agree satisfactorily with the experimental data.  相似文献   
47.
The R and M phase variants of Rhodobacter sphaeroides and Rhodobacter capsulatus were isolated. The growth rates in the dark and in the light in glucose-containing media were much higher for the Rba. sphaeroides R variant than for the M variant. For the Rba. capsulatus R and M variants, growth rates in the dark and in the light in fructose- or glucose-containing media differed insignificantly. The cells of Rba. sphaeroides and Rba. capsulatus phase variants growing in media with glucose and fructose exhibited differences in activity of the key enzymes of the Embden–Meyerhof–Parnas (EMP) and Entner–Doudoroff (ED) pathways. The oxidative pentose phosphate pathway (PPP) does not participate in glucose and fructose metabolism in the studied bacteria. Specific activity of the ED pathway enzymes was higher in dark-grown R and M variants of both Rba. sphaeroides and Rba. capsulatus than in the cells grown under light. Specific activity of the EMP enzymes was higher for the R and M variants of both cultures grown in the light than for those grown in the dark. Activities of the 2-keto-3-deoxy-6-phosphogluconate and fructose bisphosphate aldolases, the key enzymes of the ED and EMP pathways in Rba. sphaeroides M variant grown in the medium with glucose in the light or in the dark, were approximately twice those of the R variant. In the medium with fructose activities of these enzymes in both R and M variants did not change significantly depending on growth conditions. Activities of the enzymes of the EMP and ED pathways in the extracts of the Rba. capsulatus R and M cells grown with glucose or fructose did not change significantly. Cultivation of Rba. sphaeroides and Rba. capsulatus phase variants in the medium with fructose resulted in a considerably increased synthesis of 1-phosphofructokinase. Induction of 1-phosphofructokinase synthesis in Rba. sphaeroides occurred only in the light, while in Rba. capsulatus induction of this enzyme in the medium with fructose was observed both in the dark and in the light. Thus, under aerobic conditions in the dark the phase variants of both bacteria probably assimilated glucose and fructose via the ED pathway, while in the light the EMP pathway was active.  相似文献   
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The ultrathin structure of the amoeboid flagellate Thaumatomonas coloniensis Wylezich et al. has been studied. The cell is surrounded by somatic scales forming on the surface of the mitochondria. The heterodynamic flagella emerge from the small flagellar pocket. Both flagella are covered by pineal scales and thin twisted mastigonemes. The kinetosomes lie parallel to each other. The transitional zone of the flagella carries the thin-walled cylinder. The transversal plate of the flagella is above the cell surface. The flagellar root system consists of three microtubular bands and a fibrillar rhizoplast. The vesicular nucleus and Golgi apparatus are of the usual structure. The mitochondria contain tubular cristae. The extrusive organelles (kinetocysts) contain amorphous material and a capsule; they are located in cytoplasm. The capsule consists of a muff and cylinder. Osmiophilic bodies of various shapes contain crystalloid inclusions. The pseudopodia capturing the bacteria emerge from the ventral groove. The groove is armored by the two longitudinal groups of the close situated microtubules. Microbodies and symbiotic bacteria have not been discovered. The resemblance of Th. coloniensis with other thaumatomonads is discussed.  相似文献   
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