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Transient expression of inactive RB in mesenchymal stem cells impairs their adipogenic potential and is associated with hypermethylation of the PPARγ2 promoter

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Genes & Diseases 2022年第1期9卷 165-175页

作者： Mikhail Baryshev nikolai Petrov vladimir Ryabov Boris Popov Institute of Cytology Russian Academy of Sciences St.Petersburg4Tikhoretsky Av.194064St.PetersburgRussia Institute of Microbiology and Virology Riga Stradins UniversityRatsupites 5LV-1067RigaLatvia Developmental Therapeutics Branch National Cancer InstituteNational Institutes of HealthBethesdaMaryland 20892USA

The retinoblastoma gene product(pRb)is a chromatin-associated protein that can either suppress or promote activity of key regulators of tissue-specific *** found that twelve weeks after transfection of the exogenous active(ΔB/X andΔр34)or inactive(ΔS/n)forms of RB into the 10T1/2 mesenchymal stem cells and clonal selection not a single cell line did contain exogenous RB,despite being G-418 ***,the consequences of the transient production of exogenous RB had different effects on the cell ***ΔB/X andΔр34 cells transfected with active form of RB showed elevated levels of inducible adipocyte differentiation(AD).On the contrary,theΔS/n cells transfected with inactive RB mutant were insensitive to induction of AD associated with abolishing of expression of the PPARγ***,the PPARγ2 promoter in undifferentiatedΔS/n cells was hypermethylated,but all except−60 position CpG became mostly demethylated after cells exposure to *** conclude that while transient expression of inactive exogenous RB induces long term epigenetic alterations that prevent adipogenesis,production of active exogenous RBs results in an AD-promoting epigenetic *** results indicate that pRb is involved in the establishment of hereditary epigenetic memory at least by creating a methylation pattern of PPARγ2.

关键词： Adipogenic differentiation DnA methyltransferase 1 Mesenchymal stem cells MSCs RB Retinoblastoma susceptibility gene

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超宽带多注速调管的模拟研究

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电子与信息学报 2006年第1期28卷 180-184页

作者：沈斌丁耀根 Aleksandr n.Sandalov vladimir E.Rodjakin Aleksandra n.Chashurina 中国科学院电子学研究所 Radiophysics Chair

本文介绍了多注速调管的发展历史和现状,以及速调管模拟软件的发展情况。用1．5维软件Klystron -MSU和2．5维软件Arsenal-MSU对超宽带多注速调管进行了设计计算,并对计算结果进行分析,得到了比较好的输出特性。计算结果表明可以实现该... 详细信息

本文介绍了多注速调管的发展历史和现状,以及速调管模拟软件的发展情况。用1．5维软件Klystron -MSU和2．5维软件Arsenal-MSU对超宽带多注速调管进行了设计计算,并对计算结果进行分析,得到了比较好的输出特性。计算结果表明可以实现该超宽带多注速调管,其带宽10-14％,增益40-50dB,效率40-50％。

关键词：多注速调管 Klystron-MSU Arsenal-MSU 电子注通过率输出特性

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Ferroelectricity Induced by Oxygen Vacancies in Rhombohedral ZrO_(2) Thin Films

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Energy & Environmental Materials 2024年第1期7卷 229-237页

作者： Veniero Lenzi José P.B.Silva Břetislav Šmíd vladimir Matoín Cosmin M.Istrate Corneliu Ghica Judith L.MacManus-Driscoll Luís Marques Physics Center of Minho and Porto Universities(CF-UM-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal Laboratory of Physics for Materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic national Institute of Materials Physics 105 bis Atomistilor 077125Magurele Romania Department of Materials Science and Metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observed in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contribute to the ferroelectric *** findings reveal the importance of V_(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

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Surface interaction between Pd and nitrogen derived from hyperbranched polyamide towards highly effective formic acid dehydrogenation

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Journal of Energy Chemistry 2020年第1期29卷 212-216,I0008页

作者： Yancun Yu Xian Wang Changpeng Liu Fateev vladimir Junjie Ge Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina University of Chinese Academy of Sciences Beijing 100049China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources Changchun 130022JilinChina State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022JilinChina University of Science and Technology of China(USTC) Hefei 230026AnhuiChina national Research Center Kurchatov Institute Kurchatov sq.1MoscowRussia Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchaun 130022Jilin.China

Hydrogen production from formic acid decomposition(FAD)is a promising means of hydrogen energy storage and utilization in fuel *** of efficient catalysts for dehydrogenation of formic acid is a challenging *** surface chemical and electronic structure of the active catalysis components is important in formic acid decomposition at ***,the pyrdinic-nitrogen doped catalysts from hyperbranched polyamide were prepared via in situ polymerization reaction process by using activated carbon as a *** of the introduction of the polymer,the particles of the catalysts were stabilized,and the average particle diameter was only 1.64 *** mild conditions,the catalysts activities were evaluated for *** optimized Pd-n30/C catalyst exhibited high performance achieving almost full conversion,with a turnover frequency of 3481 h^-1 at 30℃.

关键词： Formic acid decomposition Hydrogen generation Hyperbranched polymer Pd catalyst

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Electrical triggering of earthquakes:results of laboratory experiments at spring-block models

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Earthquake Science 2017年第4期30卷 167-172页

作者： Victor A.novikov vladimir I.Okunev Vadim n.Klyuchkin Jing Liu Yuri Ya.Ruzhin Xuhui Shen Joint Institute for High Temperatures of Russian Academy of Sciences MoscowRussia Institute of Earthquake Science China Earthquake AdministrationBeijingChina Pushkov Institute of Terrestrial Magnetism and Radio Wave Propagation TroitskMoscow RegionRussia Institute of Crustal Dynamics China Earthquake AdministrationBeijingChina

Recently published results of field and laboratory experiments on the seismic/acoustic response to injection of direct current （DC） pulses into the Earth crust or stressed rock samples raised a question on a possibility of electrical earthquake triggering. A physical mechanism of the considered phenomenon is not clear yet in view of the very low current density （10-7-10-s A/m^2） generated by the pulsed power systems at the epicenter depth （5-10 km） of local earthquakes occurred just after the current injection. The paper describes results of laboratory ＂earthquake＂ triggering by DC pulses under conditions of a spring-block model simulated the seismogenic fault. It is experimentally shown that the electric triggering of the laboratory ＂earthquake＂（sharp slip of a movable block of the spring-block system） is possible only within a range of subcritical state of the system, when the shear stress between the movable and fixed blocks obtains 0.98-0.99 of its critical value. The threshold of electric triggering action is about 20 A/m^2 that is 7-8 orders of magnitude higher than estimated electric current density for Bishkek test site （northern Tien Shan, Kirghizia） where the seismic response to the man-made electric action was observed. In this connection, the electric triggering phenomena may be explained by contraction of electric current in the narrow conductive areas of the faults and the corresponding increase in current density or by involving the secondary triggering mechanisms like electromagnetic stimulation of conductive fluid migration into the fault area resulted in decrease in the fault strength properties.

关键词： Earthquake simulation Spring-block model Electric pulse Triggering threshold

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Selected gas response measurements using reduced graphene oxide decorated with nickel nanoparticles

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nano Materials Science 2021年第4期3卷 412-419页

作者： Ilka Simon Yulyan Haiduk Rolf Mtilhaupt vladimir Pankov Christoph Janiak Institut für Anoganische Chemie und Strukturchemie Heinrich-Heine Universität Düsseldorf 40204DüsseldorfGermany Chemical Faculty Belarusian State UniversityLenningradskaya Str.14220050 MinskBelarus Freiburg Materials Research Center and Institute for Macromolecular Chemistry Albert-Ludwigs-UniversityFreiburg79104FreiburgGermany

The work reports the synthesis of nickel nanoparticles supported on thermally reduced graphene oxides(rGO)in the ionic liquid[BMIm][nTf_(2)]through microwave decomposition ***@rGO with the polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)as binder was positively tested for its response towards the oxidizing gas nitrogen dioxide(10 ppm in air),the reducing gas carbon monoxide(3000 ppm in n_(2))and the volatile organic compound(VOC)acetone(35,000 ppm in air).The results from different gases were compared at different temperatures with the best results for nO_(2) at 200℃.Additionally,it is shown for nO_(2) gas that the ni@rGO-PEDOT:PSS polymer composite gives better results than the rGO-PEDOT:PSS polymer *** the heat treatment the oxidation state of pure nickel nanoparticles were confirmed by powder diffraction.

关键词： nickel nanoparticles Reduced graphene oxide Gas sensing nanocomposite

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Physico−mathematical model of the voltage−current characteristics of light-emitting diodes with quantum wells based on the Sah−noyce−Shockley recombination mechanism

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Journal of Semiconductors 2024年第8期45卷 25-33页

作者： Fedor I.Manyakhin Dmitry O.Varlamov vladimir P.Krylov Lyudmila O.Morketsova Arkady A.Skvortsov vladimir K.nikolaev Dinamics Strength of Machines and Resisance of MaterialsMoscow Polytechnic UniversityRussia Biomedical and Electronic Means and Technologies Vladimir State UniversityRussia Computer-Aided Design and Engineering National University of Science and Technology"MISiS"Russia

Herein,a physical and mathematical model of the voltage−current characteristics of a p−n heterostructure with quantum wells(QWs)is prepared using the Sah−noyce−Shockley(SnS)recombination mechanism to show the SnS recombination rate of the correction function of the distribution of QWs in the space charge region of diode configuration.A comparison of the model voltage−current characteristics(VCCs)with the experimental ones reveals their *** technological parameters of the structure of the VCC model are determined experimentally using a nondestructive capacitive approach for determining the impurity distribution profile in the active region of the diode structure with a profile depth resolution of up to 10Å.The correction function in the expression of the recombination rate shows the possibility of determining the derivative of the VCCs of structures with QWs with a nonideality factor of up to 4.

关键词： light-emitting diodes with quantum wells voltage−current relation nonideality factor recombination mechanism Sah−noyce−Shockley model

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Anomalously High Conductivity of Deformed Metals at the Positive Temperatures

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World Journal of Condensed Matter Physics 2012年第2期2卷 85-90页

作者： Gennady A. Markov vladimir n. Malyshev Mechanical Engineering Department Gubkin Russian State University of Oil and Gas Moscow Russia Technologies of Markov Ltd. Novosibirsk Russia

The description of experimentally observed phenomenon of abnormally high electrical conductivity—'superconductivity' (SC) at the room and higher temperatures is represented. The effect was observed in metallic monospirals of small radius curvature with high density and regular distribution of dislocations. Transition into state of SC has been observed experimentally in the range from –50 up to 3000°C at the density of transmitting current up to 2·109 A/cm2. The experimental data confirming the watched phenomenon are represented. The explanations of this phenomenon are being proposed in the framework of the dislocation model.

关键词： Metallic Monospirals Dislocation Density The Anomalously High Conductivity in Metals-Superconductivity Room and other Positive Temperatures The Velocity of Current Density Growth

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Improving the performance of power system protection using wide area monitoring systems

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Journal of Modern Power Systems and Clean Energy 2016年第3期4卷 319-331页

作者： Arun G.PHADKE Peter WALL Lei DInG vladimir TERZIJA Virginia Polytechnic Institute and State University 900 N.Glebe Rd.ArlingtonVA 22203USA Department of Electrical and Electronic Engineering University of ManchesterManchester M139PLUK School of Electrical Engineering Shandong University17923 Jingshi RoadJinan 250061Shandong ProvinceChina

Wide area monitoring(WAM) offers many opportunities to improve the performance of power system protection. This paper presents some of these opportunities and the motivation for their development. This methods include monitoring the suitability of relay characteristics,supervisory control of backup protection, more adaptive and intelligent system protection and the creation of novel system integrity protection scheme. The speed of response required for primary protection means that the role WAM in enhancing protection is limited to backup and system protection. The opportunities offered by WAM for enhancing protection are attractive because of the emerging challenges faced by the modern power system protection. The increasingly variable operating conditions of power systems are making it ever more difficult to select relay characteristics that will be a suitable compromise for all loading conditions and contingencies. The maloperation of relays has contributed to the inception and evolution of 70 % of blackouts,thus the supervision of the backup protection may prove a valuable tool for preventing or limiting the scale of blackouts. The increasing interconnection and complexity of modern power systems has made them more vulnerable to wide area disturbances and this has contributed to several recent blackouts. The proper management of these wide area disturbances is beyond the scope of most of the existing protection and new, adaptive system integrity protection schemes are needed to protect power system security.

关键词： Backup protection Blackouts Hidden failures Power system protection System integrity protection schemes Wide area monitoring Wide area protection

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Specific structural features of LnZrOx(Ln:La, Sm) mixed oxides prepared by different methods

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Progress in natural Science:Materials International 2018年第4期28卷 437-446页

作者： Tatyana Kuznetsova Tamara Kriger Yurii Chesalov AnDrey Boronin Arcadii Ishchenko Pavlos K.PAnDis vladimir Krivensov Galina Litvak Tatyana Larina Vladislav Sadykov Vassilis n.Stathopoulos Boreskov Institute of Catalysis novosibirsk State University Laboratory of Chemistry and Materials Technology Department of Electrical Engineering School of Technological Applications Technological Education Institute of Sterea Ellada

LnZrOx(Ln: La, Sm) mixed oxides of Ln: Zr = 1 were prepared by different methods(complex polymerized method, sorption of cations on starch from aqueous salt solution and conventional co-precipitation with additional redispersion of precipitate by ultra sound) and calcined at 700–1300 °C. Their specific structural features and changes were studied and discussed. Various characterization methods were used such as X-ray diffraction,Electron microscopy, Fourier-transform infrared and Raman spectroscopy, UV–Vis spectroscopy, X-Ray absorption fine structure and X-ray photoelectron *** formation of pyrochlore structure occurred at 1100–1300 °C from fluorite-like pseudocubic phase ZrO2regardless the method of preparation. This phase had a block-like structure consisting of ZrO2nanocrystals stabilized by Ln cations and residual anions such as hydroxyls and carbonates. The desorption of such anions with heating already started at 900 °C and lead to local changes of Zr cations coordination to octahedral and to the formation of pyrochlore nanodomains inclusions within fluorite-like phase. The increased cation mobility and further elimination of anions caused by further heating was accompanied by the formation of bulk pyrochlore phase at 1100–1300 °C. Even after calcination at 1300 °C the local microheterogeneity as well as defects were identified at domains boundaries or sintered microstructure. These specific features of the formed pyrochlores depend on the method of preparation.

关键词： Fluorites Pyrochlores Synthesis Powders Structure

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