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Epigenetic remodeling by DNA glycosylases during rice reproduction

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Molecular Plant 2021年第9期14卷 1433-1435页

作者： Mingzhuo Li qirui cui Xiang-Qian Zhang Tzung-Fu Hsieh Department of Plant and Microbial Biology North Carolina State UniversityRaleighNC 27695USA Plants for Human Health Institute North Carolina State UniversityNorth Carolina Research CampusKannapolisNC 28081USA College of Forestry and Landscape Architecture South China Agricultural University510642 GuangzhouChina

Cytosine methylation is a covale nt modificatio n of DNA that regulates important processes in eukaryotic genomes,including gene transcription,transposon silencing,and genomic imprinting(Law and Jacobsen,2010).DNA methylation patterns are faithfully duplicated upon cell division to ensure genome integrity and to maintain lineage-specific cell ***,DNA methylation also needs to be dynamically reprogramed or reconfigured during development to allow establishment of new cellular identity and transcriptional state,which plays a prominent role in animal development and reproduction,and is increasingly being appreciated for reproductive success in flowering plants(Walker et al.,2018;Ono and Kinoshita,2021).

关键词： al. remodeling maintain

Anisotropic Dzyaloshinskii-Moriya interaction protected by D_(2d) crystal symmetry in two-dimensional ternary compounds

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npj Computational Materials 2022年第1期8卷 1209-1215页

作者： Yonglong Ga qirui cui Yingmei Zhu Dongxing Yu Liming Wang Jinghua Liang Hongxin Yang Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China

Magnetic skyrmions,topologically protected chiral spin swirling quasiparticles,have attracted great attention in fundamental physics and ***,the discovery of two-dimensional(2D)van der Waals(vdW)magnets have aroused great interest due to their appealing physical ***,both experimental and theoretical works have revealed that isotropic Dzyaloshinskii–Moriya interaction(DMI)can be achieved in 2D magnets or ferromagnet-based ***,2D magnets with anisotropic DMI haven’t been reported ***,via using first-principles calculations,we unveil that anisotropic DMI protected by D_(2d)crystal symmetry can exist in 2D ternary compounds MCuX_(2)(M:3d transition metal(TM),X:group VIA).Interestingly,by using micromagnetic simulations,we demonstrate that ferromagnetic(FM)antiskyrmions,FM bimerons,antiferromagnetic(AFM)antiskyrmions,and AFM bimerons can be realized in the MCuX_(2)*** discovery opens up an avenue to creating antiskyrmions and bimerons with anisotropic DMI protected by D_(2d)crystal symmetry in 2D magnets.

关键词： DMI symmetry magnets

Quantum Anomalous Hall Effects Controlled by Chiral Domain Walls

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Chinese Physics Letters 2023年第3期40卷 62-67页

作者：崔琪睿梁敬华朱英梅姚雄杨洪新 National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China

We report the interplay between two different topological phases in condensed matter physics,the magnetic chiral domain wall(DW),and the quantum anomalous Hall(QAH)*** is shown that the chiral DW driven by Dzyaloshinskii–Moriya interaction can divide the uniform domain into several zones where the neighboring zone possesses opposite quantized Hall *** separated domain with a chiral edge state(CES)can be continuously modified by external magnetic field-induced domain expansion and thermal fluctuation,which gives rise to the reconfigurable QAH *** interestingly,we show that the position of CES can be tuned by spin current driven chiral DW *** two-dimensional magnets with high Curie temperature and large topological band gaps are proposed for realizing these *** present work thus reveals the possibility of chiral DW controllable QAH effects.

关键词： effect chiral topological

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钢-铝热致搅拌摩擦点焊工艺研究

新乡学院学报 2018年第6期35卷 48-51页

作者：胥锴崔强崔琪睿安徽机电职业技术学院机械工程系安徽芜湖241000 西北工业大学理学院陕西西安710072

采用热致搅拌摩擦点焊连接工艺,对DP590钢与6061铝板进行了搭接点焊实验,通过电镜扫描与拉伸试验研究了焊接接头的微观组织和力学性能。结果表明:采用热致搅拌摩擦点焊连接工艺可以获得成形较好的铝-钢异种金属点焊的搭接接头;在搅拌头... 详细信息

采用热致搅拌摩擦点焊连接工艺,对DP590钢与6061铝板进行了搭接点焊实验,通过电镜扫描与拉伸试验研究了焊接接头的微观组织和力学性能。结果表明:采用热致搅拌摩擦点焊连接工艺可以获得成形较好的铝-钢异种金属点焊的搭接接头;在搅拌头旋转速度为1 000 r/min、扎入深度为0.2 mm、停留时间为90 s及焊接压力为0.2 MPa、冷却空气流量为20 L/min的条件下,焊缝表面成形质量较好,表面光亮,退出孔较小;在搅拌针的作用下,搅拌区里的钢-铝产生了强烈的塑性剪切变形与流动,这两种材料能充分混合在一起,呈现出河流状的流动特征;剪切断裂是微孔形核长大和聚合在断口上留下的痕迹。

关键词：热致搅拌摩擦点焊点焊工艺塑性流动

合成铁磁多层膜中各向异性层间Dzyaloshinski-Moriya相互作用

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Science Bulletin 2023年第9期68卷 878-882,M0003页

作者：陈如意徐峰崔琪睿梁敬华周永健王宁潘峰薛飞杨洪新宋成 Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

Dzyaloshinskii-Moriya相互作用(DMI)在合成磁性多层膜体系和自旋电子技术中扮演着重要的作用.这种非共线相互作用在磁性多层膜体系中包括两种形式:界面DMI和层间DMI.对于界面DMI,其单易轴性和各向异性特征都已被发现,为拓扑自旋的技术... 详细信息

Dzyaloshinskii-Moriya相互作用(DMI)在合成磁性多层膜体系和自旋电子技术中扮演着重要的作用.这种非共线相互作用在磁性多层膜体系中包括两种形式:界面DMI和层间DMI.对于界面DMI,其单易轴性和各向异性特征都已被发现,为拓扑自旋的技术发展奠定了基础.然而,到目前为止,有关层间DMI的研究都是单易轴性的,层间DMI的各向异性特征尚未报道.本文结合实验和理论结果,报道了[Co/Pd]多层结构中的各向异性层间DMI,这种层间手性相互作用可引起在互为60°的两个方向上的非对称磁化翻转行为.第一性原理计算表明,层间DMI的各向异性是由面心立方结构中沿(111)面两个能量较低的高对称方向上的面内反演对称性破缺导致.各向异性层间DMI的发现不仅揭示了磁性多层膜中长程层间耦合相互作用的起源,也为基于磁性多层膜的自旋电子学器件设计提供了新的途径.

关键词：磁性多层膜对称性破缺磁化翻转各向异性自旋电子层间耦合第一性原理计算面心立方结构

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层间反对称交换耦合的前沿进展

四川师范大学学报（自然科学版） 2024年第4期47卷 427-436页

作者：杨洪新李彭朱英梅崔琪睿南京大学物理学院固体微结构物理国家重点实验室江苏南京210093 中国科学院宁波材料技术与工程研究所浙江宁波315201 新加坡国立大学苏州研究院江苏苏州215125

层间反对称交换耦合,或者层间Dzyaloshinskii-Moriya(DM)相互作用,存在于以铁磁/非磁/铁磁金属异质结为单元的多层薄膜体系中.其物理来源是体系的对称性破缺、自旋轨道耦合(spin-orbit coupling,SOC)以及Ruderman-Kittel-Kasuya-Yosida(RKKY)机制.层间DM相互作用的理论于20世纪90年代提出,但是由于其强度较小,直到2019年才被实验观测到人工反铁磁结构中的手性交换偏置效应所证实.近期的实验证明层间DM相互作用能帮助无外场自旋轨道转矩(spin-orbit torque,SOT)翻转垂直磁化,对于新兴自旋电子学器件设计意义重大.简要介绍层间DM相互作用的理论推导、相关实验现象、第一性原理的计算方法以及可能的应用,为今后层间DM相互作用相关的研究抛砖引玉.

关键词： Dzyaloshinskii-Moriya相互作用层间反对称交换耦合层间Dzyaloshinskii-Moriya相互作用 RKKY交换相互作用自旋轨道转矩效应

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Systematic screening and structural characterization of dipeptides using offline 2D LC-LTQ-Orbitrap MS:A case study of Cordyceps sinensis

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Journal of Pharmaceutical Analysis 2022年第2期12卷 263-269页

作者： Xiaodie Li Changliang Yao Yun Li Zhengming Qian c Wenlong Wei Jianqing Zhang Jiayuan Li qirui Bi Wenjia Li Yajun cui De-an Guo Shanghai Research Center for Modernization of Traditional Chinese Medicine National Engineering Laboratory for Traditional Chinese Medicine Standardization TechnologyShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China Shanghai University of Traditional Chinese Medicine Shanghai201203China Key Laboratory of State Administration of Traditional Chinese Medicine Sunshine Lake Pharma Co.LtdDongguanGuangdong523850China

Cordyceps sinensis(***)is a widely used and highly valuable traditional Chinese *** dipeptides have been detected in ***,but current scientific knowledge of its chemical makeup remains *** this study,an improved approach that integrates offline two-dimensional liquid chromatography(2D LC)separation,precursor ion list,library screening,and diagnostic ion filtering was established to systematically screen and characterize dipeptides in *** 2D LC integrating hydrophilic interaction LC and reverse phase separations was established to eliminate interference and identify the target dipeptides.A library containing the potential 400 dipeptides was created,and a precursor ion list with all theoretical precursor ions was adopted to trigger the MS/MS scan with high *** identify dipeptides,the type and connection sequence of amino acids were determined according to the product *** and Leu residues were differentiated for the first time according to the characteristic ion at m/z ***,170 dipeptides were identified or tentatively characterized from ***,and most are reported for the first time in this species *** addition,the identified dipeptides were also applied for discrimination among the three Cordyceps species,and 11 markers were *** obtained results provide a deeper understanding of the chemical basis of ***.

关键词： Dipeptides Cordyceps sinensis Two-dimensional liquid chromatography Identification Isoleucine

Data-driven Stealthy Actuator Attack against Cyber-Physical Systems

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Data-driven Stealthy Actuator Attack against Cyber-Physical ...

第三十九届中国控制会议

作者： Zhixue Zhang qirui Zhang Tao Liu Zhonghua Pang Bing cui Shuxin Jin Kun Liu Beijing Satellite Navigation Center Beijing Institute of Technology Beijing Wuzi University North China University of Technology

This paper studies the data-driven stealthy actuator attack against cyber-physical systems. The objective of the attacker is to add a certain bias to the output while keeping the detection rate of the χ detector less than a certain value. With the historical input and output data, the parameters of the system are estimated and the attack signal is the solution of a convex optimization problem constructed with the estimated parameters. The extension to the case of arbitrary detectors is also discussed. A numerical example is given to verify the effectiveness of the attack.

关键词： Cyber-physical system security Stealthy attack Data-driven

来源： cnki会议评论

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一种多反向学习的教与学优化算法

工程科学与技术 2019年第6期51卷 159-167页

作者：何杰光彭志平崔得龙李启锐广东石油化工学院计算机学院

针对原始教与学优化算法全局搜索和局部搜索协调不足、当前反向学习策略过于单一的问题,将多种反向学习策略同教与学优化算法相结合,提出一种基于多反向学习的教与学优化(MOTLBO)算法。首先,借鉴反向学习的思想,设计一种基于Sigmoid函... 详细信息

针对原始教与学优化算法全局搜索和局部搜索协调不足、当前反向学习策略过于单一的问题,将多种反向学习策略同教与学优化算法相结合,提出一种基于多反向学习的教与学优化(MOTLBO)算法。首先,借鉴反向学习的思想,设计一种基于Sigmoid函数且随进化代数逐渐变化的非线性混合反向学习模型,模型综合考虑了问题的搜索边界信息和种群的历史搜索信息;其次,在原始教与学算法教和学两个阶段的基础上,增加了基于搜索边界指导的自学习阶段,增强了种群的多样性;最后,将混合反向学习模型与算法的各阶段相结合,根据各阶段的不同特征,设计了基于均值个体、随机个体和最优个体的反向解计算方法,充分吸收种群的历史搜索经验,提高算法的收敛精度和速度。采用具有不同特征的Benchmark测试函数对算法的非线性混合反向学习模型和收敛性能进行测试,实验结果表明:非线性混合反向学习模型相对于单一的边界信息反向学习或种群信息反向学习,具有更强的全局搜索和局部探测能力;而与原始教与学优化算法及其改进算法相比,MOTLBO算法在获得较高的收敛精度和稳定性的同时保持了更快的收敛速度,其综合性能得到较大提升。此外,对扩频雷达相位编码求解的实验结果进一步表明,MOTLBO算法能有效避免陷入局部最优,亦适用于求解实际的工程优化问题。

关键词：教与学优化算法反向学习搜索边界种群信息非线性混合模型