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Retrospective and perspective of plant epigenetics in China

Journal of Genetics and Genomics 2018年第11期45卷 621-638页

作者： Cheng-guo Duan Jian-Kang Zhu Xiaofeng Cao Shanghai Center for Plant Stress Biology and Center of Excellence for Molecular Plant Sciences Chinese Academy of SciencesShanghai 200032，China Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteIN 47907USA State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China

Epigenetics refers to the study of heritable changes in gene function that do not involve changes in the DNA sequence. Such effects on cellular and physiological phenotypic traits may result from external or environmental factors or be part of normal developmental program. In eukaryotes, DNA wraps on a histone octamer(two copies of H2A, H2B, H3 and H4) to form nucleosome, the fundamental unit of chromatin. The structure of chromatin is subjected to a dynamic regulation through multiple epigenetic mechanisms, including DNA methylation, histone posttranslational modifications(PTMs), chromatin remodeling and noncoding RNAs. As conserved regulatory mechanisms in gene expression, epigenetic mechanisms participate in almost all the important biological processes ranging from basal development to environmental response. Importantly, all of the major epigenetic mechanisms in mammalians also occur in plants. Plant studies have provided numerous important contributions to the epigenetic research. For example, gene imprinting, a mechanism of parental allele-specific gene expression, was firstly observed in maize; evidence of paramutation, an epigenetic phenomenon that one allele acts in a single locus to induce a heritable change in the other allele, was firstly reported in maize and ***, some unique epigenetic mechanisms have been evolved in plants. For example, the 24-nt siRNA-involved RNA-directed DNA methylation(RdDM) pathway is plant-specific because of the involvements of two plant-specific DNA-dependent RNA polymerases, Pol IV and Pol V. A thorough study of epigenetic mechanisms is of great significance to improve crop agronomic traits and environmental adaptability. In this review, we make a brief summary of important progress achieved in plant epigenetics field in China over the past several decades and give a brief outlook on future research *** focus our review on DNA methylation and histone PTMs, the two most important aspects of epigenetic mec

关键词： Plant epigenetics DNA methylation Histone modifications Chromatin remodeling

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Multi-hybrid method for investigation of EM scattering from inhomogeneous object above a dielectric rough surface

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Science China(Physics,Mechanics & Astronomy) 2012年第10期55卷 1781-1790页

作者： LI Jie guo LiXin HE Qiong WEI Bing School of Science Xidian UniversityXi'an 710071China National Supercomputing Center in Shenzhen Shenzhen 518055China

An iterative strategy combining Kirchhoff approximation （KA） method is presented in this paper to study the interactions between KA is applied to study scattering from underlying rough surfaces with the hybrid finite element-boundary integral （FE-BI） the inhomogeneous object and the underlying rough surface. whereas FE-BI deals with scattering from the above target. Both two methods use updated excitation sources. Huygens equivalence principle and an iterative strategy are employed to consider the multi-scattering effects. This hybrid FE-BI-KA scheme is an improved and generalized version of previous hybrid Kirchhoff approximation-method of moments （KA-MoM）. This newly presented hybrid method has the following advantages：（1） the feasibility of modeling multi-scale scattering problems （large scale underlying surface and small scale target）; （2） low memory requirement as in hybrid KA-MoM; （3） the ability to deal with scattering from inhomogeneous （including coated or layered） scatterers above rough surfaces. The numerical results are given to evaluate the accuracy of the multi-hybrid technique; the computing time and memory requirements consumed in specific numerical simulation of FE-BI-KA are compared with those of MoM. The convergence performance is analyzed by studying the iteration number variation caused by related parameters. Then bistatic scattering from inhomogeneous object of different configurations above dielectric Gaussian rough surface is calculated and the influences of dielectric compositions and surface roughness on the scattering pattern are discussed.

关键词： electromagnetic scattering hybrid method rough surface inhomogeneous target

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Preparation of SiC powders by carbothermal reduction with bamboo charcoal as renewable carbon source

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Journal of Advanced Ceramics 2013年第2期2卷 128-134页

作者： Xingzhong guo Lin ZHU Wenyan LI Hui YANG Department of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China

Bamboo charcoal was expected to be a renewable carbon source for carbide materials in carbothermal reduction because of its superior *** powders with characteristic shapes were fabricated by carbothermal reduction with industrial silica sol and bamboo charcoal particles as silicon and carbon sources respectively,and the effects of reacting temperature and time on shape evolutions and properties of the as-prepared SiC powders were *** silica sol/bamboo charcoal system was firstly transformed into SiO_(2)/C system by the transition of silica sol and graphitization of bamboo charcoal,and the carbothermal reduction between SiO_(2) and C occurred at/above 1600℃.The characteristic shapes of SiC particles were transformed from string-beads-like to dumbbell-like and rod-like with the increase of reacting *** prepared SiC powders are expected to become new raw material for silicon carbide ceramic composites.

关键词： carbides chemical synthesis X-ray diffraction(XRD) microstructure

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Boundedness of Some Maximal Commutators in Hardy-type Spaces with Non-doubling Measures

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Acta Mathematica Sinica,English Series 2007年第6期23卷 1129-1148页

作者： guo En HU Yan MENG Da Chun YANG Department of Applied Mathematics University of Information Engineering P. O. Box 1001-747 Zhengzhou 450002 P. R. China School of Information Renmin University of China Beijing 100872 P. R. China School of Mathematical Sciences Beijing Normal University Beijing 100875 P. R. China

Let μ be a non-negative Radon measure on R^d which satisfies only some growth conditions. Under this assumption, the boundedness in some Hardy-type spaces is established for a class of maximal Calderón-Zygmund operators and maximal commutators which are variants of the usual maximal commutators generated by Calder6ón- Zygmund operators and RBMO（μ） functions, where the Hardytype spaces are some appropriate subspaces, associated with the considered RBMO（μ） functions, of the Hardv soace H^I（μ） of Tolsa.

关键词： maximal commutator Calderon Zygmund operator RBMO(μ) Hardy-type space non-doubling measure

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A Generalization of the Mean Size Formula of Wavelet Packets in L_p

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1475-1486页

作者： Song LI guo Mao WANG Zhi Song LIU Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China

The purpose of this paper is to investigate the mean size formula of wavelet packets in Lp for 0 〈 p ≤ ∞. We generalize a mean size formula of wavelet packets given in terms of the p-norm joint spectral radius and we also give some asymptotic formulas for the Lp-norm or quasi-norm on the subdivision trees. All results will be given in the general setting,

关键词： mean size joint spectral radii wavelet packet subdivision sequence

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Hybrid Particle Swarm Optimization with Differential Evolution for Numerical and Engineering Optimization

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International Journal of Automation and computing 2018年第1期15卷 103-114页

作者： guo-Han Lin Jing Zhang Zhao-Hua Liu College of Electrical and Information Engineering Hunan University College of Electrical and Information Hunan Institute of Engineering School of Information and Electrical Engineering Hunan University of Science and Technology

In this paper, a hybrid particle swarm optimization （PSO） algorithm with differential evolution （DE） is proposed for numerical benchmark problems and optimization of active disturbance rejection controller （ADRC） parameters. A chaotic map with greater Lyapunov exponent is introduced into PSO for balancing the exploration and exploitation abilities of the proposed algorithm. A DE operator is used to help PSO jump out of stagnation. Twelve benchmark function tests from CEC2005 and eight real world opti- mization problems from CEC2011 are used to evaluate the performance of the proposed algorithm. The results show that statistically, the proposed hybrid algorithm has performed consistently well compared to other hybrid variants. Moreover, the simulation results on ADRC parameter optimization show that the optimized ADRC has better robustness and adaptability for nonlinear discrete-time systems with time delays.

关键词： Particle swarm optimization (PSO) active disturbance rejection control (ADRC) differential evolution algorithm chaoticmap parameter tuning.

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A DUAL-SURFACE DAMAGE MODEL AND EVALUATION FOR NATURAL SOILS WITHIN THE THERMOMECHANICAL FRAMEWORK

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Acta Mechanica Solida Sinica 2008年第1期21卷 85-94页

作者： Xuan guo Chenggang Zhao Dajun Yuan Mengshu Wang Tunnel and Underground of Engineering Experienmental Research Center Beijing Jiaotong University Beijing 100044 China School of Civil Engineering ＆ Architecture Beijing Jiaotong University Beijing 100044 China

Naturally deposited or residual soils exhibit more complicated behavior than remolded clays. A dual-surface damage model for structured soils is developed based on the thermodynamics framework established in our first paper. The shift stresses and the transformation between the generalized dissipative stress space and actual stress space are established following a systematic procedure. The corresponding constitutive behavior of the proposed model is determined, which reflects the internal structural configuration and damage behavior for geomaterials. Four evolution variables κj^i（i=D, R;j=V, S） and the basic parameters λ, s, v and e0 are introduced to account for the progressive loss of internal structure for natural clays. A series of fully triaxial tests and isotropic compression tests are performed for structured and reconstituted samples of Beijing and Zhengzhou natural clays. The validation of the proposed model is examined by comparing the numerical results with the experimental data.

关键词： dual-surface damage model triaxial tests structured soils thermomechanical approach compressibility

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Synthesis of Novel 1-Alkyl-2-chloro(alkoxy)-1H-indole 3-Carbaldehyde Oximes and Oxime-ethers(esters) Derivatives

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Chemical Research in Chinese Universities 2009年第4期25卷 465-473页

作者： GAO Wen-tao GAO De-peng guo Hui Institute of Superfine Chemicals Bohai University Jinzhou 121000 P. R. China

A convenient synthesis of 1-alkyl-2-chloro-1H-indole-3-carbaldehyde oximes（5a―5d） and 1-alkyl-2-phenoxy-1H-indole-3-carbaldehyde oximes（6a―6d） from 2-indolone was completed via the Vilsmeier-Haack reac-tion,with N-alkylation and oximation as the key *** improved one-pot method for the synthesis of 1-alkyl-2-alkoxy-1H-indole-3-carbaldehyde oximes（7a―7h） from 1-alkyl-2-chloro-1H-indole-3-carbaldehydes（3a―3d） was *** Williamson reactions and esterification reactions were performed and the oxime-ethers and oxime-esters were synthesized,*** new synthesized compounds（3a―11d） were characterized by 1H NMR,IR,MS,and elemental analysis.

关键词： Oxime Indole Vilsmeier-Haack reaction Williamson reaction One-pot method

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An Anti-Quantum Authentication Protocol for Space Information Networks Based on Ring Learning with Errors

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Journal of Communications and Information Networks 2021年第3期6卷 301-311页

作者： Junyan guo Ye Du Xuesong Wu Meihong Li Beijing Key Laboratory of Security and Privacy in Intelligent Transportation Beijing Jiaotong UniversityBeijing 100044China

With the continuous development of satellite communication and Internet of things technology,more and more devices can access space information networks(SIN)and enjoy satellite services everywhere in the ***,due to the openness of the air-to-ground channel,the device will face a series of security threats when accessing SIN,such as replay attacks,eavesdropping attacks,impersonation attacks,and man-in-the-middle *** security threats will lead to illegal entity access and further endanger the reliability and availability of the *** scholars have proposed many enhanced security access authentication protocols,most of them have been proved to have security *** addition,with the development of quantum computing,the previous authentication protocols based on some asymmetric cryptographic mechanisms such as discrete logarithm and elliptic curve cryptographic mechanisms may face new security *** this context,this paper proposes a novel antiquantum access authentication protocol based on ring learning with errors(RLWE),which meets more security requirements and greatly reduces the authentication delay through *** the security analysis and performance analysis,it is shown that our protocol can be more suitable for delaysensitive IoT devices to access SIN while ensuring higher security.

关键词： space information networks access security anti-quantum authentication protocol

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Pore pressure observation: pressure response of probe penetration and tides

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Acta Oceanologica Sinica 2019年第7期38卷 107-113页

作者： Tao Liu Guanli Wei Hailei Kou Lei guo Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266061China College of Engineering Ocean University of ChinaQingdao 266100China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China

Excess pore water pressure is an important parameter that can be used to analyze certain physical characteristics of *** this paper,the excess pore water pressure of subseafloor sediment and its variation with tidal movement was measured following the installation of a wharf in Qingdao,China by using a fiber Bragg grating(FBG)*** results indicated that this FBG piezometer is effective in the *** measured variation of excess pore water pressure after installation is largely explained by the dissipation of excess pore water *** dissipation rate can be used to estimate the horizontal consolidation coefficient,which ranged from 1.3×10^–6 m^2/s to 8.1×10^–6 m^2/*** measured values during tidal phases are associated with the variability of tidal pressure on the seafloor and can be used to estimate the compressibility and the permeability of the sediment during tidal *** volume compression coefficient estimated from tidal oscillation was approximately 2.0×10^–11 Pa^–1,which was consistent with the data from the laboratory *** findings of this paper can provide useful information for in situ investigations of subseafloor sediment.

关键词： pore pressure in situ observation penetration tidal load

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