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1.
Khutoryan Eduard Kuleshov Alexei Ponomarenko Sergey Lukin Konstantin Tatematsu Yoshinori Tani Masahiko 《Journal of Infrared, Millimeter and Terahertz Waves》2021,42(6):671-683
Journal of Infrared, Millimeter, and Terahertz Waves - Various regimes of hybrid, bulk-surface, modes being excited in the clinotron oscillator with a sheet electron beam and nonuniform grating... 相似文献
2.
Konstantin V. Dergilev Evgeny K. Shevchenko Zoya I. Tsokolaeva Irina B. Beloglazova Ekaterina S. Zubkova Maria A. Boldyreva Mikhail Yu. Menshikov Elizaveta I. Ratner Dmitry Penkov Yelena V. Parfyonova 《International journal of molecular sciences》2020,21(24)
Cell therapy of the post-infarcted myocardium is still far from clinical use. Poor survival of transplanted cells, insufficient regeneration, and replacement of the damaged tissue limit the potential of currently available cell-based techniques. In this study, we generated a multilayered construct from adipose-derived mesenchymal stromal cells (MSCs) modified to secrete stem cell factor, SCF. In a rat model of myocardium infarction, we show that transplantation of SCF producing cell sheet induced activation of the epicardium and promoted the accumulation of c-kit positive cells in ischemic muscle. Morphometry showed the reduction of infarct size (16%) and a left ventricle expansion index (0.12) in the treatment group compared to controls (24–28%; 0.17–0.32). The ratio of viable myocardium was more than 1.5-fold higher, reaching 49% compared to the control (28%) or unmodified cell sheet group (30%). Finally, by day 30 after myocardium infarction, SCF-producing cell sheet transplantation increased left ventricle ejection fraction from 37% in the control sham-operated group to 53%. Our results suggest that, combining the genetic modification of MSCs and their assembly into a multilayered construct, we can provide prolonged pleiotropic effects to the damaged heart, induce endogenous regenerative processes, and improve cardiac function. 相似文献
3.
Albul V. I. Bychkov V. B. Gusev K. E. Demidov V. S. Demidova E. V. Kurchanov A. F. Luk'yashin V. E. Sokolov A. Yu. 《Measurement Techniques》2003,46(8):810-814
A monitor is proposed based on ultrasonic production when ionizing radiation passes through a medium. The recording element is a 0.2 mm aluminum plate mounted in a ceramic acoustic converter AC in the form of a wedge of thickness 2 mm. The low plate thickness minimizes the beam parameter distortion, while special technology used in the AC provides high sensitivity. The device has been calibrated in the proton beam from the ITEP accelerator at 200 MeV with 2·109–6·1010 particles in a pulse and a pulse length of 70 nsec. 相似文献
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6.
The kinetics of electronic processes in vidicon phototargets based on semiconductor-insulator structures with a narrow-gap semiconductor is considered taking into account charge drain in the insulator layer and relaxation of the nonequilibrium depletion region in the semiconductor layer. The integration time, threshold sensitivity, and resolution at various intensities of incident radiation are estimated. 相似文献
7.
Artem Sokolov Darrell Whitley Andre’ da Motta Salles Barreto 《Genetic Programming and Evolvable Machines》2007,8(3):221-237
This paper evaluates different forms of rank-based selection that are used with genetic algorithms and genetic programming.
Many types of rank based selection have exactly the same expected value in terms of the sampling rate allocated to each member
of the population. However, the variance associated with that sampling rate can vary depending on how selection is implemented.
We examine two forms of tournament selection and compare these to linear rank-based selection using an explicit formula. Because
selective pressure has a direct impact on population diversity, we also examine the interaction between selective pressure
and different mutation strategies. 相似文献
8.
Scientific-Technical Center “Atomtekhénergo.” Leningrad Nuclear Power Plant. N. V. Sultanov Institute of Nuclear Reactors,
Russian Scientific Center “Kurchatovskii institut.” Translated from Atomnaya énergiya, Vol. 76, No. 6, pp. 470–473, June,
1994. 相似文献
9.
V. A. Vdovin S. A. Sokolov V. A. Cherepenin A. M. Afonin V. I. Kanavetz 《Journal of Infrared, Millimeter and Terahertz Waves》1987,8(1):49-54
Theoretical and experimental studies of high-power, relativistic surface-wave microwave Cherenkov generators are briefly considered. Some simulation and experiment results included, the experimentation being made in mm-wave region. 相似文献
10.
A. R. Malosiev V. G. Plotnichenko A. O. Rybaltovskii V. O. Sokolov V. V. Koltashev 《Inorganic Materials》2003,39(3):304-308
The formation of Ge nanoclusters in bulk and thin-film germanosilicate glass samples prepared by vapor deposition techniques and then heat-treated in molecular hydrogen at 800°C was studied by Raman scattering and optical spectroscopy. The results demonstrate that the formation of Ge nanoclusters is accompanied by a substantial increase in the concentration of oxygen-deficient germanium centers and the formation of OH groups. A mechanism of nanocluster formation is proposed. The effects of different process parameters on nanocluster growth in the course of preform fabrication and fiber drawing are examined. 相似文献