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81.
Polymorphisms c.202G > A of prothrombin F2 gene, c.1691G > A of coagulation factor V F5 gene, c.675delinsG of plasminogen activator 1 gene, and (?5)T > C Kozak gene of thrombocytic receptor were studied in the Russian and Moldavian ethnic groups. We have found no association between these polymorphisms and the risk of ischemic stroke development in both ethnic groups. No association was revealed between the risk of stroke development and various combinations of the single nucleotide polymorphisms examined in the sample of ischemic stroke patients from Russia.  相似文献   
82.
Polymorphisms of the genes of the glutamatergic system EAAT2, GRIA1, and GRIA2 have been analyzed in patients with sporadic motor neuron disease (MND) from Russia. The disease is not associated with polymorphic alleles of the genes studied, which indicates that EAAT2, GRIA1, and GRIA2 play an insignificant role in the pathogenesis of sporadic MND.  相似文献   
83.
In experiments on electron cyclotron resonance (ECR) heating of plasma at the second harmonic of the electron gyrofrequency in the L-2M stellarator, the effect of partial reflection of high-power gyrotron radiation from the ECR heating region located in the center of the plasma column was revealed. The reflection coefficient is found to be on the order of 10?3. The coefficient of reflection of an extraordinary wave from the second-harmonic ECR region is calculated in the one-dimensional full-wave model. The calculated and measured values of the reflection coefficient are found to coincide in order of magnitude.  相似文献   
84.
The IVS9-675C > A polymorphism of the HIF-1alpha gene was analyzed in patients with acute ischemic stroke and in a control group. The genotype and allele frequencies proved to significantly differ between the two groups. Allele C and genotypes containing this allele were associated with a higher risk of stroke in the Moscow population.  相似文献   
85.
Polymorphisms c.202G > A of prothrombin F2 gene, c.1691G > A of coagulation factor V F5 gene, c.675delinsG of plasminogen activator1 gene, and (-5)T > C Kozak gene of thrombocytic receptor were studied in the Russian and Moldavian ethnic groups. We have found no association between these polymorphisms and the risk of ischemic stroke development in both ethnic groups. No association was revealed between the risk of stroke development and various combinations of the single nucleotide polymorphisms examined in the sample of ischemic stroke patients from Russia.  相似文献   
86.
The role of variants of the gene encoding arachidonate 5-lipoxygenase-activating protein (ALOX5AP) as possible susceptibility factors for acute stroke were examinated. Two ALOX5AP gene polymorphisms (SG13S114 (rs10507391) and SG13S32 (rs9551963)), which previously had shown association with the risk of ischemic stroke in other populations, were studied. These single nucleotide polymorphisms were analyzed using a sample of acute stroke patients (N = 1320) and a control sample (N = 467). No statistically significant associations were found between acute stroke and the ALOX5AP gene polymorphisms examined.  相似文献   
87.
The characteristics of a new MIG-3 gyrotron complex for creating and heating plasma in the L-2M stellarator are presented. The first experimental results using the complex are reported. The complex consists of two three-electrode GYCOM gyrotrons of the new generation with electron beam energy recuperation, a high-voltage modulator that enables both separate and simultaneous operation of the two gyrotrons, and a control/data-recording unit. The total specific power to be inserted into plasma reaches 5 MW/m3 when both gyrotrons in operation.  相似文献   
88.
Backscattering of gyrotron radiation (θ = π) by short-wavelength density fluctuations (k = 30 cm?1) in the plasma of the L-2M stellarator was studied under conditions of electron cyclotron resonance (ECR) plasma heating at the second harmonic of the electron gyrofrequency (75 GHz). The scattering of the O-wave emerging due to the splitting of the linearly polarized gyrotron radiation into the X- and O-waves was analyzed. The signal obtained after homodyne detection of scattered radiation is a result of interference of the reference signal, the quasi-steady component, and the fast oscillating component. The coefficients of reflection of the quasi-steady component, R = 2 (Y), and fast oscillating component, R 2 (Y), of scattered radiation are estimated. The growth of the R 2 (Y) coefficient from 3.7 × 10?4 to 5.2 × 10?4 with increasing ECR heating power from 190 to 430 kW is found to correlate with the decrease in the energy lifetime from 1.9 to 1.46 ms. The relative density of short-wavelength fluctuations is estimated to be 〈n 2 〉/〈n e 2 〉 = 3 × 10?7. It is shown that the frequencies of short-wavelength fluctuations are in the range 10–150 kHz. The recorded short-wavelength fluctuations can be interpreted as structural turbulence, the energy of which comprises ~10% of the total fluctuations energy. Simulations of transport processes show that neoclassical heat fluxes are much smaller than anomalous ones. It is suggested that short-wavelength turbulence plays a decisive role in the anomalous heat transport.  相似文献   
89.
Plasma Physics Reports - A layer of regolith with a 1.35% Al content was irradiated from the side of the reactor supporting plate with a microwave pulse with an intensity of 10–15 kW...  相似文献   
90.
The influence of magnetic configurations with magnetic hills or wells on the parameters of a plasma column and turbulence characteristics were studied in experiments in which the plasma was created and heated by a microwave beam at the second harmonic of the electron cyclotron frequency. Calculations show that, for 〈β〉=(1.5?2)×10?, a configuration with a magnetic well takes place and the Mercier criterion for stability of the ideal MHD modes is satisfied. It is shown that the compensation of the Shafranov shift of the plasma column by a transverse (vertical) field (B v /B 0 =5×10?3) leads to a configuration with a magnetic hill in which the Mercier stability criterion is violated in the central region of the plasma column. It is experimentally shown that the stored plasma energy in the magnetic-hill configuration is reduced by one-half in comparison with the magnetic-well configuration. In the case of a magnetic hill, the energy of fluctuations increases both in the plasma core and near the separatrix, and the quasi-regular components of the wavelet spectra grow. When the Shafranov shift is compensated only partially (B v/B 0~3×10?3) and the system is near the instability threshold, the stored plasma energy and the central electron temperature are somewhat higher, and the radiation power of fast electrons from non-Maxwellian tails at the second harmonic of the electron gyrofrequency decreases. It is found that the wavelet spectra of fluctuations change, the coherence coefficient for spectral components increases, and the radial electric field near the separatrix decreases.  相似文献   
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