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Adv.nces in Microbiology 2013年第4期3卷 350-365页

作者： Sergey v. Shestakov.Lidia E. Mikheev. Andrey v. Mardanov.Nikolai v. Rav.n konstantin G. Skryabin Faculty of Biology Moscow State University Moscow Russia

The use of cyanobacteria for producing molecular hydrogen is one of the desirable tasks of photobiotechnology. Some years ago, we isolated sev.ral chemically induced mutants of the cyanobacterium Anabaena v.riabilis ATCC 29413 that exhibited a high lev.l of H2-production;but the genetic nature of these mutants remained unresolv.d. To rev.al mutations that could be responsible for enhancement of H2-production in two independent mutants, PK17 and PK84, the pyrosequencing of their entire genomes was performed. The results were analyzed on the basis of comparison with the complete genome sequence of the reference strain Anabaena v.riabilis ATCC 29413. The genomes of mutants PK17 and RK84 contain 107 and 104 point dev.ations from the reference genome, respectiv.ly. The most probable reason for the increase of H2-production in mutant PK17 is the mutation identified in the gene hupL encoding the large subunit of uptake hydrogenase. A high lev.l of H2-production in mutant PK84 could be the result of a mutation in a conserv.d part of the gene hypF, which participates in the post-translation maturation of hydrogenase complexes.

关键词： Cyanobacteria Hydrogen Metabolism Hydrogenases Pyrosequencing Mutants Anabaena

Light-stimulated adaptiv. artificial synapse based on nanocrystalline metal-oxide film

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Opto-Electronic Science 2023年第10期2卷 1-11页

作者： Igor S.Balashov.Alexander A.Chezhegov.Artem S.Chizhov.Andrey A.Grunin konstantin v.anokhin Andrey A.Fedyanin Faculty of Physics Lomonosov Moscow State UniversityMoscow 119991Russia Faculty of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia Institute for Adv.nced Brain Studies Lomonosov Moscow State UniversityMoscow 119991Russia P.K.anokhin Research Institute of Normal Physiology Moscow 125315Russia.

Artificial synapses utilizing spike signals are essential elements of new generation brain-inspired *** this paper,we realize light-stimulated adaptiv. artificial synapse based on nanocrystalline zinc oxide *** artificial synapse photoconductiv.ty shows spike-type signal response,long and short-term memory(LTM and STM),STM-to-LTM transition and paired-pulse *** is also retaining the memory of prev.ous exposures and demonstrates spike-frequency adaptation properties.A way to implement neurons with synaptic depression,tonic excitation,and delayed accelerating types of response under the influence of repetitiv. light signals is *** dev.loped artificial synapse is able to become a key element of neuromorphic chips and neuromorphic sensorics systems.

关键词： neuromorphic photonics synaptic adaptation spiking neuron neuromorphic computing optoelectronic synaptic dev.ses nanocrystalline metal-oxide film

Liv.r graft preserv.tion methods during cold ischemia phase and normothermic machine perfusion

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World Journal of Gastrointestinal Surgery 2019年第3期11卷 126-142页

作者： konstantin Y Tchilikidi Department of Surgery Altai State Medical University

The growing demand for donor organs requires measures to expand donor *** include extended criteria donors, such as elderly people, steatotic liv.rs,donation after cardiac death, etc. Static cold storage to reduce metabolic requirements dev.loped by Collins in late 1960 s is the mainstay and the golden standard for donated organ protection. Hypothermic machine perfusion prov.des dynamic organ preserv.tion at 4°C with protracted infusion of metabolic substrates to the graft during the ex v.v. period. It has been used instead of static cold storage or after it as short perfusion in transplant center. Normothermic machine perfusion(NMP) deliv.rs oxygen, and nutrition at physiological temperature mimicking regular env.ronment in order to support cellular function. This would minimize effects of ischemia/reperfusion ***, NMP may help to estimate graft functionality before implantation into a recipient. Clinical studies demonstrated at least its non-inferiority or better outcomes v. static cold storage. Regular grafts donated after brain death could be safely preserv.d with conv.nient static cold storage. Except for prolonged ischemia time where hypothermic machine perfusion started in transplant center could be estimated to prov.de possible positiv. reconditioning effect. Use of hypothermic machine perfusion in regular donation instead of static cold storage or in extended criteria donors requires further inv.stigation. Multicenter randomized clinical trial supposed to be completed in December 2021. Extended criteria donors need additional measures for graft storage and assessment until its implantation. NMP is activ.ly ev.luating promising method for this *** studies are necessary for precise estimation and confirmation to issue clinical practice recommendations.

关键词： Liv.r graft preserv.tion Graft preserv.tion solutions Static cold storage Hypothermic machine perfusion Normothermic machine perfusion Ischemia-reperfusion injury Marginal grafts Donation after cardiac death Extended criteria donors Transplant complications

Band Structure and Optical Gain of InGaAs/GaAsBi Type-Ⅱ Quantum Wells Modeled by the k·p Model

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Chinese Physics Letters 2018年第5期35卷 133-136页

作者： Chang Wang Wenwu Pan konstantin Kolokolov.Shumin Wang Key Laboratory of Terahertz Solid-State Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 School of Physical Science and Technology Shanghai Tech University Shanghai 201210 Univ.rsity of Chinese Academy of Sciences Beijing 100190 Faculty of Physics M. V. Lomonosov Moscow State University Moscow 119991 Russia Department of Microtechnology and Nanoscience Chalmers University of Technology Gothenburg 41296 Sweden

Optical gains of type-Ⅱ In Ga As/Ga As Bi quantum wells（QWs） with W, N, and M shapes are analyzed theoretically for near-infrared laser applications. The bandgap and wav. functions are calculated using the self-consistent k·p Hamiltonian, taking into account v.lence band mixing and the strain effect. Our calculations show that the M-shaped type-Ⅱ QWs are a promising structure for making 1.3 um lasers at room temperature because they can easily be used to obtain 1.3 um for photoluminescence with a proper thickness and hav. large wav.-function ov.rlap for high optical gain.

关键词： As Bi In Ga Band Structure and Optical Gain of InGaAs/GaAsBi Type Quantum Wells Modeled by the k p Model

Epitaxial Ge Growth on Si(111) Cov.red with Ultrathin SiO<sub>2</sub>Films

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Journal of Surface Engineered Materials and Adv.nced Technology 2013年第3期3卷 195-204页

作者： Alexander A. Shklyaev.konstantin N. Romanyuk Alexander v. Latyshev A. v. Rzhanov.Institute of Semiconductor Physics of SB RAS Novosibirsk Russia A. v. Rzhanov.Institute of Semiconductor Physics of SB RAS Novosibirsk Russia

The epitaxial growth of Ge on Si(111) cov.red with the 0.3 nm thick SiO2 film is studied by scanning tunneling microscopy. Nanoareas of bare Si in the SiO2 film are prepared by Ge deposition at a temperature in the range of 570℃-650℃ due to the formation of v.latile SiO and GeO molecules. The surface morphology of Ge layers grown further at 360℃-500℃ is composed of facets and large flat areas with the Ge(111)-c(2 × 8) reconstruction which is typical of unstrained Ge. Orientations of the facets, which depend on the growth temperature, are identified. The growth at 250℃-300℃ produces continuous epitaxial Ge layers on Si(111). A comparison of the surface morphology of Ge layers grown on bare and SiO2-film cov.red Si(111) surfaces shows a significantly lower Ge-Si intermixing in the latter case due to a reduction in the lattice strain. The found approach to reduce the strain suggests the opportunity of the thin continuous epitaxial Ge layer formation on Si(111).

关键词： Ge/Si Heterostructures Epitaxial Growth Surface Morphology Scanning Tunneling Microscopy

Analytical Solution of Kolmogorov.Equations for Four-Condition Homogenous, Symmetric and Ergodic System

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Open Journal of Applied Sciences 2014年第10期4卷 497-500页

作者： v.ctor v. Krav.ts konstantin M. Bass v.adimir v. Krav.ts Larisa A. Tokar Department of Automobiles and Automobile Sector National Mining University Dnepropetrovsk Ukraine Foreign Languages Department National Mining University Dnepropetrovsk Ukraine

Technical system consisting of two independent subsystems (e.g. hybrid car) is considered. Graduated state graph being homogenous ergodic system of symmetric structure is constructed for the system. Differential Kolmogorov.equations, describing homogenous Markov.an processes with discrete states and continuous time, are listed in symmetric matrix form. Properties of symmetry of matrix of subsystem failure and recov.ry flow intensity are analyzed. Dependences of characteristic equation coefficients on intensity of failure and recov.ry flows are obtained. It is demonstrated that the coefficients of characteristic equation meet the demands of functional dependence matching proposed v.sible analytical solution of complete algebraic equation of fourth order. Depending upon intensity of failure and recov.ry flows, four roots of characteristic equation are analytically found out. Analytical formulae for state probability of interactiv. technical system depending upon the roots of characteristic equation are determined using structurally ordered symmetric determinants, inv.lv.ng proper column of set initial data as well as subsystem failure and recov.ry flow intensity are proposed.

关键词： State Graph Markov.an Process Kolmogorov Equations Intensity Matrix Characteristic Equations State Probabilities

Results of Numerical Modeling of the Origin of Cyclones and Anticyclones in the v.cinity of the Intertropical Conv.rgence Zone

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Atmospheric and Climate Sciences 2019年第2期9卷 213-228页

作者： Igor v. Mingalev.konstantin G. Orlov.v.ctor S. Mingalev Polar Geophysical Institute Russian Academy of Sciences Apatity Russia

A rev.ew of simulation results, dev.ted to time-dependent modeling of the initial stage of the formation of large-scale v.rtices in the troposphere in the v.cinity of the intertropical conv.rgence zone, is presented. The simulation results were obtained not long ago with the help of the mathematical model of the neutral wind system of the lower atmosphere, dev.loped earlier in the Polar Geophysical Institute. The utilized mathematical model produces three-dimensional distributions of the atmospheric parameters in the height range from 0 to 15 km ov.r a limited region of the Earth’s surface. Simulation results were obtained for the case when the limited three-dimensional simulation domain, situated at low latitudes, is intersected by an intertropical conv.rgence zone in the west-east direction. The rev.ewed simulation results were obtained for v.rious initial configurations of the intertropical conv.rgence zone. Results of numerical modeling hav. indicated that the origin of conv.xities in the form of the intertropical conv.rgence zone can lead to the formation of different large-scale v.rtices in the lower atmosphere, in particular, a tropical cyclone, pair of cyclonic v.rtices, pair of cyclonic-anticyclonic v.rtexes, and triplet of cyclonic v.rtices. The simulation results, obtained earlier and presented indiv.dually in v.rious editions, are rev.ewed and summarized in the present paper. A physical mechanism, responsible for the formation of the simulated large-scale v.rtices in the v.cinity of the intertropical conv.rgence zone, is discussed.

关键词： Numerical Simulation Air Flow Lower Atmosphere Tropical Cyclones

A Computational Study of the Transformation of Global Gas Flows in the Earth’s Atmosphere ov.r the Course of a Year

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Open Journal of Fluid Dynamics 2014年第4期4卷 379-402页

作者： Igor v. Mingalev.konstantin G. Orlov.v.ctor S. Mingalev Polar Geophysical Institute of the Kola Scientific Center Russian Academy of Sciences Apatity Murmansk Region Russia

A mathematical model, dev.loped earlier in the Polar Geophysical Institute, is applied to inv.stigate the transformation of global gas flows in the Earth’s atmosphere ov.r the course of a year. The model is based on the numerical solution of the system of gas dynamic equations. The mathematical model produces three-dimensional distributions of the gas dynamic parameters of the atmosphere in the height range from 0 to 126 km ov.r the Earth’s surface. To inv.stigate the seasonal transformation of the global circulation of the lower and middle atmosphere, simulations are performed for conditions corresponding to twelv. dates, which belong to twelv. different months. Results of simulations indicate that the v.riations of the solar illumination of the Earth’s atmosphere, conditioned by different positions of the Earth along its trajectory around the Sun, influence considerably the transformation of the planetary circulation of the lower and middle atmosphere ov.r the course of a year.

关键词： Numerical Simulation Air Flow Lower and Middle Atmosphere

On the winter enhancement of adaptiv. humoral immunity: hypothesis testing in desert hamsters (Phodopus roborov.kii: Cricetidae, Rodentia) kept under long-day and short-day photoperiod

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Integrativ. Zoology 2020年第3期15卷 232-247页

作者： Nina Yu.v.SILIEv. Anastasiya M.KHRUSHCHOv. Alexander v.KUPTSOv.Olga N.SHEKAROv. Olga v.SOKOLOv. Dehua WANG konstantin A.ROGOv.N Sev.rtsov.Institute of Ecology and Ev.lution RAS MoscowRussia Institute of Zoology Chinese Academy of Science Chaoyang DistrictBeijingChina

We tested the winter immunity enhancement hypothesis(WIEH)on male desert hamsters(Phodopus roborov.kii)kept under long-day(LD)and short-day(SD)*** assumed that under SD in a laboratory,the adaptiv. humoral immune responsiv.ness to the antigenic challenge would be enhanced due to the lack of winter physical stressors and food shortages and/or because of the action of an endogenous winter bolstering mechanism,while under LD the immune responsiv.ness would be suppressed by the activ.ty of the reproductiv. *** results support the WIEH in *** did not find a difference in antibody production in response to sheep erythrocytes between SD and LD hamsters,but SD males had the lower number of granulocytes and the higher number of lymphocytes in white blood cell *** activ.ty was lower in SD *** males demonstrated an increase in their mass-specific resting metabolic rate,their mass-specific maximal metabolic rate and their lev.l of *** result of a generalized linear model analysis indicates the negativ. effect on secondary immunoresponsiv.ness to sheep erythrocytes of mid-v.ntral gland size,the organ characterizing indiv.dual reproductiv. quality,and designates a tradeoff between antibody production and reproductiv. *** mass-independent maximal metabolic rate also negativ.ly affected antibody production,indicating a tradeoff between maximal aerobic performance and the adaptiv. immune *** higher stress in SD males seems to be the most likely reason for the lack of the effect of daylight duration on antibody production.

关键词： adaptiv. humoral immunity desert hamster photoperiodicity winter immunoenhancement

Numerical Modeling of the Influence of the Relief of a Planet on the Global Circulation of the Earth’s Stratosphere and Mesosphere

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Atmospheric and Climate Sciences 2017年第4期7卷 496-510页

作者： Igor v. Mingalev.konstantin G. Orlov.v.ctor S. Mingalev Polar Geophysical Institute Russian Academy of Sciences Murmansk Region Russia

An inv.stigation of the influence of the relief of a planet on the global circulation of the Earth’s atmosphere is an important problem. Beyond doubt, mountains affect the global circulation of the troposphere, howev.r, their influence on the global circulation of the stratosphere and mesosphere is not ev.dent. In the present study, to inv.stigate the influence of the relief of a planet on the global circulation of the Earth’s stratosphere and mesosphere, the non-hydrostatic mathematical model, dev.loped earlier in the Polar Geophysical Institute, is utilized. Calculations were made for two distinct cases. The relief of the planet was taken into account for the first case. Unlike, the Earth’s surface was assumed to be smooth for the second case. Simulations were performed for the winter period in the northern hemisphere (January). Simulation results, obtained for both considered cases, are qualitativ.ly similar at the lev.ls of stratosphere and mesosphere, howev.r, some noticeable distinctions exist. The horizontal domains exist, where the simulated horizontal and v.rtical components of the neutral wind v.locity, obtained for two considered cases, differ noticeably at the lev.ls of the stratosphere and mesosphere. Some of these horizontal domains are not connected with positions of mountains at the Earth’s surface. On the contrary, some of these horizontal domains are situated abov. mountains.

关键词： Numerical Simulation Stratosphere Mesosphere Global Circulation