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Sequence Divergence of Microsatellites and Phylogeny Analysis in Tetraploid Cotton Species and Their Putative Diploid Ancestors

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Journal of Integrative Plant Biology 2005年第12期47卷 1418-1430页

作者： Wang-zhen GUO dong FANG Wen-Duo YU Tian-zhen ZHANG State Key Laboratory of Crop Genetics and Germplasm Enhancement Cotton Research Institute Nanjing Agricultural University Nanjing 210095 China

To determine the level of microsatellite sequence differences and to use the information to construct a phylogenetic relationship for cultivated tetraploid cotton （Gossypium spp.） species and their putative diploid ancestors, 10 genome-derived microsatellite primer pairs were used to amplify eight species, including two tetraploid and six diploid species, in Gossypium. A total of 92 unique amplicons were resolved using polyacrylamide gel electrophoresis. Each amplicon was cloned, sequenced, and analyzed using standard phylogenetic software. Allelic diversities were caused mostly by changes in the number of simple sequence repeat （SSR） motif repeats and only a small proportion resulted from interruption of the SSR motif within the locus for the same genome. The frequency of base substitutions was 0.5%-1.0% in different genomes, with only few indels found. Based on the combined 10 SSR flanking sequence data, the homology of A-genome diploid species averaged 98.9%, even though most of the amplicons were of the same size, and the sequence homology between G. gossypioides （Ulbr.） Standl. and three other D-genome species （G. raimondii Ulbr., G. davidsonii Kell., and G. thurberi Tod.） was 98.5%, 98.6%, and 98.5%, respectively. Phylogenetic trees of the two allotetraploid species and their putative diploid progenitors showed that homoelogous sequences from the A- and D-subgenome were still present in the polyploid subgenomes and they evolved independently. Meanwhile, homoelogous sequence interaction that duplicated loci in the polyploid subgenomes became phylogenetic sisters was also found in the evolutionary history of tetraploid cotton species. The results of the present study suggest that evaluation of SSR variation at the sequence level can be effective in exploring the evolutionary relationships among Gossypuim species.

关键词： diploid Gossypium microsatellite phylogenetic tree simple sequence repeat (SSR) tetraploid.

A reduced-order extrapolation algorithm based on CNLSMFE formulation and POD technique for two-dimensional Sobolev equations

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Applied Mathematics(A Journal of Chinese Universities) 2014年第2期29卷 171-182页

作者： LIU Qun TENG Fei LUO zhen-dong School of Mathematics and Computer Science Guizhou Normal University School of Mathematics Sciences Kaili college School of Mathematics and Physics North China Electric Power University

A reduced-order extrapolation algorithm based on Crank-Nicolson least-squares mixed finite element （CNLSMFE） formulation and proper orthogonal decomposition （POD） technique for two-dimensional （2D） Sobolev equations is established. The error estimates of the reduced-order CNLSMFE solutions and the implementation for the reduced-order extrapolation algorithm are provided. A numerical example is used to show that the results of numerical computations are consistent with theoretical conclusions. Moreover, it is shown that the reduced-order extrapolation algorithm is feasible and efficient for seeking numerical solutions to 2D Sobolev equations.

关键词： Reduced-order extrapolation aigorithm Crank-Nicolson least*squares mixed finite element for-mulation proper orthogonal decomposition technique Sobolev equations.

Analytical solution for 1D consolidation of unsaturated soil with mixed boundary condition

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第1期14卷 61-70页

作者： zhen-dong SHAN Dao-sheng LING Hao-jiang DING MOE Key Lab of Soft Soils and Geo-environmental Engineering Zhejiang University Institute of Engineering Mechanics China Earthquake Administration

Based on consolidation equations proposed for unsaturated soil, an analytical solution for 1D consolidation of an unsaturated single-layer soil with nonhomogeneous mixed boundary condition is developed. The mixed boundary condition can be used for special applications, such as tests occur in laboratory. The analytical solution is obtained by assuming all material parameters remain constant during consolidation. In the derivation of the analytical solution, the nonhomogeneous boundary condition is first transformed into a homogeneous boundary condition. Then, the eigenfunction and eigenvalue are derived according to the consolidation equations and the new boundary condition. Finally, using the method of undetermined coefficients and the orthogonal relation of the eigenfunction, the analytical solution for the new boundary condition is obtained. The present method is applicable to various types of boundary conditions. Several numerical examples are provided to investigate the consolidation behavior of an unsaturated single-layer soil with mixed boundary condition.

关键词： Unsaturated soil Consolidation Mixed boundary condition Analytical solution

Extended scintillation phase gradient autofocus in future spaceborne P-band SAR mission

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Science China(Information Sciences) 2021年第11期64卷 216-232页

作者： Yifei JI zhen dong Yongsheng ZHANG Qilei ZHANG Baidong YAO College of Electronic Science and Technology National University of Defense Technology East China Research Institute of Electronic Engineering

A future spaceborne P-band synthetic aperture radar(SAR) working system will be inevitably influenced by ionospheric scintillation, which tends to cause azimuth decorrelation and azimuth-imaging degradation. The scintillation phase error(SPE) history spatially varies by 2 D scenes, and this leads to the complexity of SPE estimation and compensation. In this paper, to address this problem, an approach based on the extended scintillation phase gradient autofocus(ESPGA) technique has been proposed. ESPGA is composed of three modules: local estimation, overall estimation, and correction. First, it employs the block PGA(BPGA) to estimate SPE associated with the local block. Second, by taking advantage of information redundancy of SPE estimates, azimuth splicing and range interpolation are applied to estimate the overall SPE distribution across the whole scene. Then, the estimation result corresponding to the overall SPE is considered to compensate the spatial-variant SPE and mitigate scintillation impacts on the spaceborne SAR images. Finally, a processing experiment based on a simulated image derived from an airborne P-band SAR real scene is conducted to demonstrate the effectiveness of the proposed methodology.

关键词： synthetic aperture radar (SAR) ionospheric scintillation scintillation phase error (SPE) extended scintillation phase gradient autofocus (ESPGA) spaceborne P-band SAR

Study of the Authenticity and Credibility of QQ Chat Records

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Journal of Harbin Institute of Technology(New Series) 2014年第6期21卷 63-66页

作者： zhen-Xing dong Long Chen Institute of Computer Forensics Chongqing University of Posts and Telecommunications School of Information Science and Technology Southwest Jiaotong University

Digital evidence investigation in QQ software is the current research *** order to identify the authenticity and credibility of QQ chat records,the method based on attacking QQ chat records is ***,an evaluation model on checking the authenticity of QQ chat records is *** cases on kinds of changing QQ chat records are *** challenge in identifying the authenticity of QQ chat records is ***,case study on attacking QQ chat records is proposed to check the relationship between the authenticity of QQ chat records and the difficulty of changing them.A couple of experiments on changing QQ chat records are finished to find how difficult changing records is and whether there are clues left on changing them or ***,a kind of QQ chat forensic process is presented,which can help for digital evidence investigation in the authenticity and credibility of QQ chat *** practices in QQ forensic cases show that it works well.

关键词： digital evidence investigation in QQ forensic identification QQ chat records authenticity credibility

Enhancing the compatibility of the amyloid-dye hybrid nanostructure for improved photo-biocatalysis

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Journal of Energy Chemistry 2023年第3期78卷 430-437,I0012页

作者： zhen dong Yanying Wang Qin Yang Dan Li Peng Wu College of Chemistry Sichuan UniversityChengdu 610064SichuanChina Analytical&Testing Centre State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610064SichuanChina College of Biomass Science and Engineering Sichuan UniversityChengdu 610064SichuanChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007HenanChina

Artificial photosynthesis is significant for renewable energy generation,sustainable development,and environmental ***-protein hybrids are promising for developing photosynthesis mimics(e.g.,photo-biocatalysis),but their performances are far lower than the plant photosystems,partially because of the incompatibility between dye and the protein matrix that limits excited state electron transfer of the included ***,using ThT-insulin amyloid assembly as a model system,we proposed that increasing the dye-protein compatibility could lead to the improved photo-biocatalytic performance.A ThT derivative,ThTPD,was designed with the same electron acceptor but extended π-conjugated donor *** integrated into the insulin amyloid,the extended π-conjugated donor structure allowed increased binding affinity and energy with the amyloid matrix,thus better electron transport to the mediator to drive the photocatalytic ***,compared with ThT, ThTPD exhibited improved light absorption and longer excited state *** photo-biocatalytic performance of ThTPD-insulin amyloid was greatly improved as compared with that of ThT in reduced nicotinamide adenine dinucleotide(NADH) *** integrating with NADH-dependent L-glutamate reductase,the efficiency of the ThTPD-insulin amyloid hybrid was 2.8-fold higher than that of ThT in glutamate generation,showing promising feature in biocatalytic solar-to-chemical conversion.

关键词： Photo-biocatalysis Dye-protein assembly Insulin amyloid ThT Compatibility

Theoretical calculations and evaluations of n+^(23)Na reaction

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Nuclear Science and Techniques 2016年第4期27卷 193-205页

作者： zhen-dong Wu Hai-Ying Liang Yin-Lu Han Department of Nuclear Physics China Institute of Atomic Energy

The data for neutron-induced reactions are indispensable in a lot of applications of nuclear science and technologies. All reaction cross sections, angular distributions, energy spectra, and double-differential cross sections of neutron, proton, deuteron, triton, and alpha-particle emissions are consistently calculated and analyzed for n+^(23)Na reactions at incident neutron energies below200 Me V, based on nuclear theoretical models. The calculated results are compared with the experimental data and the evaluated data in the ENDF/B-VII, JENDL-4.0,and JEFF-3.2 libraries. In most cases, the calculated results describe the corresponding experimental data well. At the resonance energy region, evaluated experimental data are adopted to fit to the resonance structures.

关键词：计算结果诱发反应评价中子能量实验数据双微分截面反应截面共振能量

A Stabilized Crank-Nicolson Mixed Finite Element Method for Non-stationary Parabolized Navier-Stokes Equations

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Acta Mathematicae Applicatae Sinica 2017年第2期33卷 409-416页

作者： Yan-jie ZHOU Fei TENG zhen-dong LUO School of Science Beijing Technology and Business University Beijing 100048 China School of Mathematics and Physics North China Electric Power University Beijing 102206 China

In this study, a time semi-discrete Crank-Nicolson （CN） formulation with second-order time accu- racy for the non-stationary parabolized Navier-Stokes equations is firstly established. And then, a fully discrete stabilized CN mixed finite element （SCNMFE） formulation based on two local Gauss integrals and parameter- free with the second-order time accuracy is established directly from the time semi-discrete CN formulation. Thus, it could avoid the discussion for semi-discrete SCNMFE formulation with respect to spatial variables and its theoretical analysis becomes very simple. Finaly, the error estimates of SCNMFE solutions are provided.

关键词： parabolized Navier-Stokes equations stabilized Crank-Nicolson mixed finite element formulation error estimate

Nonnegative correlation coding for image classification

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Science China(Information Sciences) 2016年第1期59卷 106-119页

作者： zhen dong Wei LIANG Yuwei WU Mingtao PEI Yunde JIA Beijing Laboratory of Intelligent Information Technology School of Computer ScienceBeijing Institute of Technology

Feature coding is one of the most important procedures in the bag-of-features model for image classification. In this paper, we propose a novel feature coding method called nonnegative correlation *** order to obtain a discriminative image representation, our method employs two correlations: the correlation between features and visual words, and the correlation between the obtained codes. The first correlation reflects the locality of codes, i.e., the visual words close to the local feature are activated more easily than the ones distant. The second correlation characterizes the similarity of codes, and it means that similar local features are likely to have similar codes. Both correlations are modeled under the nonnegative constraint. Based on the Nesterov's gradient projection algorithm, we develop an effective numerical solver to optimize the nonnegative correlation coding problem with guaranteed quadratic convergence. Comprehensive experimental results on publicly available datasets demonstrate the effectiveness of our method.

关键词： image classification correlation coding nonnegativity locality similarity