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Ferroelectric-to-relaxor transition and ultrahigh electrostrictive effect in Sm^(3+)-doped Pb(Mg_(1/3)Nb_(2/3))O_(3)-PbTiO_(3)ferroelectrics ceramics

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Journal of Materials Science & Technology 2023年第34期165卷 75-84页

作者： Yunyao Huang Leiyang Zhang Wenjing Shi Qingyuan Hu vladimir Shur Xiaoyong Wei Li Jin Electronic Materials Research Laboratory Key Laboratory of the Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburg 620000Russia

Rare-earth Sm^(3+)-doped Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.25PbTiO_(3)(PMN-0.25PT)ferroelectric ceramics with doping amounts between 0%-3%were developed via a conventional solid-state *** doping effect of Sm^(3+)ions on the PMN-0.25PT matrix was systematically investigated on the basis of the phase structure,temperature-dependent dielectric,ferroelectric,and electrotechnical *** to the disruption of long-range ferroelectric order,the addition of Sm^(3+)ions effectively lowers the Tm(temperature corresponding to maximum permittivity)of the samples,leading to enhanced relaxor ferroelectric(RFE)characteristic and superior electric field-induced strain(electrostrain)properties at room ***,a considerable large-signal equivalent piezoelectric coefficient d∗_(33)of 2376 pm/v and a very small hysteresis were attained in the PMN-0.25PT component doped with 2.5 mol.%Sm^(3+).The findings of piezoelectric force microscopy indicate that the addition of Sm^(3+)increases the local structural heterogeneity of the PMN-0.25PT matrix and that the enhanced electromechanical performance is due to the dynamic behavior of polar ***,strong temperature-dependent electrostrain and electrostrictive coefficient Q33 are observed in the critical region around Tm in all Sm^(3+)-modified PMN-0.25PT ceramic samples *** work elucidates the phase transition behavior of Sm^(3+)-doped PMN-0.25PT and reveals a critical region where electrostrictive properties can be greatly improved due to a strong temperature-dependent characteristic.

关键词： PMN-PT ceramics Sm^(3+)doping,Equivalent piezoelectric coefficient,Local structural heterogeneity,Electrostrictive effect

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射频等离子体改性PTFE表面液滴撞击接触起电对润湿性的影响

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中国表面工程 2023年第6期36卷 145-154页

作者：李昱鹏孟祥任刘玉霞霍磊雷明凯 STARINSKIY Sergey v TEREKHOv vladimir 大连理工大学材料科学与工程学院大连116024 俄罗斯科学院西伯利亚分院热物理研究所俄罗斯新西伯利亚630090

液滴撞击固体表面是自然界的常见现象,研究超疏水表面的液滴撞击对其润湿性的影响,对于超疏水性材料的潜在应用具有重要的科学意义。采用3、10、20 min氧等离子体处理(OPT)和1 min八氟环丁烷等离子体聚合沉积(PPD)的等离子体方法改性聚... 详细信息

液滴撞击固体表面是自然界的常见现象,研究超疏水表面的液滴撞击对其润湿性的影响,对于超疏水性材料的潜在应用具有重要的科学意义。采用3、10、20 min氧等离子体处理(OPT)和1 min八氟环丁烷等离子体聚合沉积(PPD)的等离子体方法改性聚四氟乙烯(PTFE)表面,获得具有不同尺寸和间距的微/纳米锥的超疏水PTFE表面,研究射频等离子体改性PTFE表面的液滴静态接触角、滚动角及液滴撞击动力学行为,分析在不同个数液滴撞击后PTFE表面的润湿性和液滴撞击行为变化,确定PTFE表面液滴撞击起电效应的影响机制。结果表明:通过1~9个液滴撞击后,PTFE表面的静态接触角随撞击液滴数量增加而减小,导致静态接触角低于150°;液滴滚动角随撞击液滴数量增加而增大,造成液滴滚动角高于10°。撞击液滴的接触时间随撞击液滴数量增加而增大,回弹系数随撞击液滴数量增加而减小。随撞击液滴数量增加,回弹液滴的正电荷和PTFE表面的负电压增大,PTFE表面的负电荷对液滴产生强吸引作用,导致低粘附超疏水性被破坏。3 min OPT和1 min PPD改性PTFE表面的纳米锥间距小,密度大,表面负电荷量增加明显,造成PTFE表面的疏水性降低的程度最显著。研究结果可为改善超疏水稳定性的表面织构设计提供理论依据。

关键词：超疏水性表面液滴撞击接触起电聚四氟乙烯(PTFE) 接触角

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Miniature,highly sensitive MOSCAP ring modulators in co-optimized electronic-photonic CMOS

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Photonics Research 2022年第1期10卷 I0001-I0007页

作者： HAYK GEvORGYAN ANATOL KHILO MARK T.WADE vladimir M.STOJANOvIC MILOS A.POPOvIC Department of Electrical and Computer Engineering Boston UniversityBostonMassachusetts 02215USA Ayar Labs Inc. EmeryvilleCalifornia 94608USA Department of Electrical Engineering and Computer Sciences University of California BerkeleyBerkeleyCalifornia 94709USA

Convergence of high-performance silicon photonics and electronics,monolithically integrated in state-of-the-art CMOS platforms,is the holy grail for enabling the ultimate efficiencies,performance,and scaling of electronicphotonic *** requires the emergence of platforms that combine state-of-the-art RF transistors with optimized silicon photonics,and a generation of photonic device technology with ultralow energies,increased operating spectrum,and the elimination of power-hungry thermal *** this paper,in a co-optimized monolithic electronics-photonics platform(GlobalFoundries 45 CLO),we turn the metal-oxide-semiconductor(MOS) field-effect transistor’s basic structure into a novel,highly efficient MOS capacitor ring *** has the smallest ring cavity(1.5 μm radius),largest corresponding spur-free free spectral range(FSR=8.5 THz),and record 30 GHz/v shift efficiency in the O-band among silicon modulators demonstrated to *** 1 v_(pp) RF drive,we show an open optical eye while electro-optically tuning the modulator to track over 400 pm(69 GHz) change in the laser wavelength(using 2.5 v_(DC) range).A 90 GHz maximum electro-optic resonance shift is demonstrated with under 40 nW of power,providing a strong nonthermal tuning mechanism in a CMOS photonics *** modulator has a separately optimized body layer but shares the gate device layer and the gate oxide with 45 nm transistors,while meeting all CMOS manufacturability design *** type of convergent evolution of electronics and photonics may be the future of platforms for high-performance systemson-chip.

关键词： tuning modulator electronic

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基于现场试井数据和岩心驱替试验的采油初期渗透率演化规律

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岩土力学 2023年第3期44卷 834-842页

作者： KOZHEvNIKOv v.Evgenii TURBAKOv S.Mikhail RIABOKON P.Evgenii GLADKIKH A.Evgeniy POPLYGIN v.vladimir GUZEv A.Mikhail 戚承志彼尔姆国立科研理工大学石油和天然气技术系俄罗斯彼尔姆614990 俄罗斯科学院远东分院应用数学研究所俄罗斯符拉迪沃斯托克690041 北京建筑大学土木与交通工程学院中国北京100044

油气开采过程中渗透率预测是一个非常重要的问题。由于油气储量衰竭导致渗透率降低,储层压力下降(有效压力增加),导致油气生产时间增加。对有效压力导致渗透率降低的问题进行了大量研究,主要是通过各种方法建立渗透率模型,如岩心驱替试... 详细信息

油气开采过程中渗透率预测是一个非常重要的问题。由于油气储量衰竭导致渗透率降低,储层压力下降(有效压力增加),导致油气生产时间增加。对有效压力导致渗透率降低的问题进行了大量研究,主要是通过各种方法建立渗透率模型,如岩心驱替试验和现场试井。前期研究结果表明,渗透率对有效压力具有幂律或指数依赖性,然而,预测渗透率的困难在于滞后现象,其原因尚不完全清楚。一些学者利用储层力学模型模拟渗透率以及解释滞后的原因,但该模型在油气生产初期有效压力波动较小时并不适用。在这项工作中,分析Perm地区北部一个油田的试井数据得出:生产初期的储层渗透率很大程度上取决于流体产出量。基于陆相储层的试井数据,得到一个描述采油初期渗透率变化的模型。为验证该模型,根据专门开发的程序对陆相储层样品进行岩心驱替试验。岩心驱替结果表明,从试井数据中获得的模型具有高收敛性。利用计算机断层扫描(computed tomography,简称CT)和扫描电镜(scanning electron microscope,简称SEM)研究岩心孔隙的属性和结构,发现天然胶体的迁移是生产初期低黏土岩石渗透率下降的主要原因。

关键词：渗透率渗透率滞后胶体迁移岩心驱替多孔介质

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Selective footprints and genes relevant to cold adaptation and other phenotypic traits are unscrambled in the genomes of divergently selected chicken breeds

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Journal of Animal Science and Biotechnology 2023年第3期14卷 887-907页

作者： Michael N.Romanov Alexandra S.Abdelmanova vladimir I.Fisinin Elena A.Gladyr Natalia A.volkova Olga A.Koshkina Andrey N.Rodionov Anastasia N.vetokh Igor v.Gusev Dmitry v.Anshakov Olga I.Stanishevskaya Arsen v.Dotsev Darren K.Griffin Natalia A.Zinovieva L.K.Ernst Federal Research Centre for Animal Husbandry DubrovitsyPodolskMoscow RegionRussia School of Biosciences University of KentCanterburyUK Federal State Budget Scientific Institution Federal Research Centre“All-Russian Poultry Research and Technological Institute”of the Russian Academy of Sciences Sergiev PosadMoscow RegionRussia Breeding and Genetic Centre“Zagorsk Experimental Breeding Farm”–Branch of the Federal Research Centre“All-Russian Poultry Research and Technological Institute”of the Russian Academy of Sciences Sergiev PosadMoscow RegionRussia Russian Research Institute of Farm Animal Genetics and Breeding–Branch of the L.K.Ernst Federal Research Centre for Animal Husbandry St.PetersburgRussia

Background The genomes of worldwide poultry breeds divergently selected for performance and other phenotypic traits may also be affected by,and formed due to,past and current admixture *** to diverse environments,including acclimation to harsh climatic conditions,has also left selection footprints in breed *** Using the Chicken 50K_CobbCons SNP chip,we genotyped four divergently selected breeds:two aboriginal,cold tolerant Ushanka and Orloff Mille Fleur,one egg-type Russian White subjected to artificial selection for cold tolerance,and one meat-type White *** of selective sweeps were determined in the studied breeds using three methods:(1)assessment of runs of homozygosity islands,(2)F_(ST) based population differential analysis,and(3)haplotype differentiation *** regions of true selection signatures were identified by two or more methods or in two or more *** these regions,we detected 540 prioritized candidate genes supplemented them with those that occurred in one breed using one statistic and were suggested in other *** them,SOX5,ME3,ZNF536,WWP1,RIPK2,OSGIN2,DECR1,TPO,PPARGC1A,BDNF,MSTN,and beta-keratin genes can be especially mentioned as candidates for cold *** factors may be involved in regulating some of these important genes(e.g.,TPO and BDNF).Conclusion Based on a genome-wide scan,our findings can help dissect the genetic architecture underlying various phenotypic traits in chicken *** include genes representing the sine qua non for adaptation to harsh *** tolerance in acclimated chicken breeds may be developed following one of few specific gene expression mechanisms or more than one overlapping response known in cold-exposed individuals,and this warrants further investigation.

关键词： Acclimation Adaptation Chicken breeds Cold tolerance Divergent selection Genetic diversity Genomewide scan Phenotypic traits Selective sweeps

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Prediction of van Hove singularity systems in ternary borides

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npj Computational Materials 2023年第1期9卷 247-257页

作者： Yang Sun Zhen Zhang Andrew P.Porter Kirill Kovnir Kai-Ming Ho vladimir Antropov Department of Physics Xiamen University361005 XiamenChina Department of Physics and Astronomy Iowa State UniversityAmesIA 50011USA Department of Chemistry Iowa State UniversityAmesIA 50011USA Ames National Laboratory U.S.Department of EnergyAmesIA 50011USA

A computational search for stable structures among bothαandβphases of ternary ATB4 borides(A=Mg,Ca,Sr,Ba,Al,Ga,and Zn,T is 3d or 4d transition elements)has been *** found thatα-ATB4 compounds with A=Mg,Ca,Al,and T=v,Cr,Mn,Fe,Ni,and Co form a family of structurally stable or almost stable *** systems are metallic in non-magnetic states and characterized by the formation of the localized molecular-like state of 3d transition metal atom dimers,which leads to the appearance of numerous van Hove singularities in the electronic *** closeness of such singularities to the Fermi level can be easily tuned by electron *** the atoms in the middle of the 3d row(Cr,Mn,and Fe),these singularities led to magnetic instabilities and magnetic ground states with a weakly metallic or semiconducting *** states appear as non-trivial coexistence of the different spin ladders formed by magnetic dimers of 3d *** magnetic states can be characterized as an analog of the spin glass *** attempts to produce MgFeB4 and associated challenges are discussed,and promising directions for further synthetic studies are formulated.

关键词： metallic ternary magnetic

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Multi-agent reinforcement learning for edge information sharing in vehicular networks

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Digital Communications and Networks 2022年第3期8卷 267-277页

作者： Ruyan Wang Xue Jiang Yujie Zhou Zhidu Li Dapeng Wu Tong Tang Alexander Fedotov vladimir Badenko School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China Advanced Network and Intelligent Connection Technology Key Laboratory of Chongqing Education Commission of China Chongqing400065China Key Laboratory of Ubiquitous Sensing and Networking in Chongqing Chongqing400065China Peter the Great St.Petersburg Polytechnic University Polytechnicheskaya29St.Petersburg195251Russia

To guarantee the heterogeneous delay requirements of the diverse vehicular services,it is necessary to design a full cooperative policy for both vehicle to Infrastructure(v2I)and vehicle to vehicle(v2v)*** paper investigates the reduction of the delay in edge information sharing for v2v links while satisfying the delay requirements of the v2I ***,a mean delay minimization problem and a maximum individual delay minimization problem are formulated to improve the global network performance and ensure the fairness of a single user,respectively.A multi-agent reinforcement learning framework is designed to solve these two problems,where a new reward function is proposed to evaluate the utilities of the two optimization objectives in a unified ***,a proximal policy optimization approach is proposed to enable each v2v user to learn its policy using the shared global network *** effectiveness of the proposed approach is finally validated by comparing the obtained results with those of the other baseline approaches through extensive simulation experiments.

关键词： vehicular networks Edge information sharing Delay guarantee Multi-agent reinforcement learning Proximal policy optimization

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Advances in the development of new biomarkers for Alzheimer’s disease

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Translational Neurodegeneration 2022年第1期11卷 601-624页

作者： Timofey O.Klyucherev Pawel Olszewski Alena A.Shalimova vladimir N.Chubarev vadim v.Tarasov Misty M.Attwood Stina Syvänen Helgi B.Schiöth Department of Neuroscience Functional PharmacologyUniversity of Upp-salaUppsalaSweden Department of Pharmacology Institute of PharmacyI.M.Sechenov First Moscow State Medical UniversityMoscowRussia Institute of Translational Medicine and Biotechnology I.M.Sechenov First Moscow State Medical UniversityMoscowRussia Department of Public Health and Caring Sciences Rudbeck LaboratoryUppsala UniversityUppsalaSweden.

Alzheimer’s disease(AD)is a complex,heterogeneous,progressive disease and is the most common type of neurodegenerative *** prevalence of AD is expected to increase as the population ages,placing an additional burden on national healthcare *** is a large need for new diagnostic tests that can detect AD at an early stage with high specificity at relatively low *** development of modern analytical diagnostic tools has made it possible to determine several biomarkers of AD with high specificity,including pathogenic proteins,markers of synaptic dysfunction,and markers of inflammation in the *** is a considerable potential in using microRNA(miRNA)as markers of AD,and diagnostic studies based on miRNA panels suggest that AD could potentially be determined with high accuracy for individual *** of the retina with improved methods of visualization of the fundus are also showing promising results for the potential diagnosis of the *** review focuses on the recent developments of blood,plasma,and ocular biomarkers for the diagnosis of AD.

关键词： Alzheimer’s disease Amyloid beta peptides Biomarkers Blood Cytokines Inflammation MicroRNA Ocular biomarkers

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Siberian silkmoth outbreaks surpassed geoclimatic barrier in Siberian Mountains

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Journal of Mountain Science 2020年第8期17卷 1891-1900页

作者： KHARUK viacheslav I. IM Sergei T. SOLDATOv vladimir v. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036 Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041 Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014 Russia Russian Center of Forest Protection Academgorodok 50A/2Krasnoyarsk660036 Russia

Siberian silkmoth(SSM,Dendrolimus sibiricus Tschetv.)is the most important defoliator of Siberian pine(Pinus sibirica Du Tour)and fir(Abies sibirica Ledeb.)***-induced SSM outbreaks are one of the major driving factors of successions within the taiga *** is suggested that climate change impacted the SSM range and life *** analyzed the migration of alpine and northerly SSM outbreak boundaries in Siberia and the impact of the climate variables and topography on the outbreak *** used time-series scenes(multispectral data,and vegetation indexes EvI and NDII)in combination with field studies,climate variables,and GIS *** found that SSM outbreaks in the area of alpine boundary shifted about 370 m uphill since the mid of *** outbreak onset was promoted by increased dryness and active temperatures and decreased root zone moisture content in the spring-early summer *** terrain topography strongly affected SSM outbreak onset and ***,the outbreak was located at the middle elevations on the gentle concave southeastern slopes,which are the favorable insect habitats between *** the outbreak expanded uphill and downhill,to steeper slopes,and both concave and convex *** with elevation range expansion,SSM surpassed its northern historical outbreak boundary:the potential outbreaks’boundary moved about 300 km *** warming contributes to SSM migration into former outbreak free conifer stands located in highlands and at northern latitudes.

关键词： Insect outbreaks Remote sensing monitoring Insect ranges expansion Siberian silkmoth Forest health Conifer mortality

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Disease modifying treatment of spinal cord injury with directly reprogrammed neural precursor cells in non-human primates

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World Journal of Stem Cells 2021年第5期13卷 452-469页

作者： vladimir P Baklaushev Oleg v Durov vladimir A Kalsin Eugene v Gulaev Sergey v Kim Ilya L Gubskiy veronika A Revkova Ekaterina M Samoilova Pavel A Melnikov Dzhina D Karal-Ogly Sergey v Orlov Alexander v Troitskiy vladimir P Chekhonin Alexander v Averyanov Jan-Eric Ahlfors Biomedical Research Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBA of RussiaMoscow 115682MoskvaRussia Department of Neurosurgery Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBAMoscow 115682MoskvaRussia Department of Anesthesiology N.N.Blokhin Russian Cancer Research CentreMoscow 115478MoskvaRussia Radiology and Clinical Physiology Scientific Research Center Federal center of brain research and neurotechnologies of the Federal Medical Biological AgencyMoscow 117997Russia Department of Neurobiology Serbsky National Medical Research Center for Psychiatry and NarcologyMoscow 119992MoskvaRussia Department of Primatology Russian Acad Med SciResearch Institute of Medical PrimatologySochi 119992SochiRussia Department of vascular Surgery Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBA of RussiaMoscow 115682MoskvaRussia Department of Basic and Applied Neurobiology V.P.Serbsky Federal Medical Research Center for Psychiatry and NarcologyRussia Department of Medical Nanobiotechnology Pirogov Russian National Research Medical University(RNRMU)Moscow 115682MoskvaRussia New World Laboratories Laval H7V 4A7QuebecCanada

BACKGROUND The development of regenerative therapy for human spinal cord injury(SCI)is dramatically restricted by two main challenges:the need for a safe source of functionally active and reproducible neural stem cells and the need of adequate animal models for preclinical *** reprogramming of somatic cells into neuronal and glial precursors might be a promising solution to the first *** use of non-human primates for preclinical studies exploring new treatment paradigms in SCI results in data with more translational relevance to human *** To investigate the safety and efficacy of intraspinal transplantation of directly reprogrammed neural precursor cells(drNPCs).METHODS Seven non-human primates with verified complete thoracic SCI were divided into two groups:drNPC group(n=4)was subjected to intraspinal transplantation of 5 million drNPCs rostral and caudal to the lesion site 2 wk post injury,and lesion control(n=3)was injected identically with the equivalent volume of *** Follow-up for 12 wk revealed that animals in the drNPC group demonstrated a significant recovery of the paralyzed hindlimb as well as recovery of somatosensory evoked potential and motor evoked potential of injured *** resonance diffusion tensor imaging data confirmed the intraspinal transplantation of drNPCs did not adversely affect the morphology of the central nervous system or cerebrospinal fluid *** immunohistochemical analysis showed that drNPCs maintained SOX2 expression characteristic of multipotency in the transplanted spinal cord for at least 12 wk,migrating to areas of axon growth *** Our data demonstrated that drNPC transplantation was safe and contributed to improvement of spinal cord function after acute SCI,based on neurological status assessment and neurophysiological recovery within 12 wk after *** functional improvement described was not associated with neuronal differentiation of th

关键词： Direct cell reprogramming Neural precursor cells Directly reprogrammed neural precursor cells Spinal cord injury Nonhuman primates Regenerative therapy,Evoked potentials

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