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Bionic optimization research of soil cultivating component design

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Science China(Technological Sciences) 2009年第4期52卷 955-965页

作者： guo ZhiJun ZHOU Zhili ZHANG Yi lI Zhongli College of Vehicle and Motive Power Engineering Henan University of Science&TechnologyLuoyang 471003China

The basic biomechanical laws that apply to the clawed toes of animals with powerful digging abilities and the optimal bionic design of curved soil cultivating components with an analogous contour were researched in a novel way. First, the curvature and profile of the inside contour line of a field mouse’s clawed toe were analyzed. The finite element method (FEM) was then used to simulate the working process in order to study the changing characteristics of the working resistance of bionic soil- engag- ing surfaces and the stress field of the processed soil. A straight-line cultivating component was used for comparative analysis. In accordance with the simulation results, a series of soil cultivating com- ponents of varying design were manufactured. An indoor soil bin experiment was carried out to meas- ure their working resistance and validate the results of the FEM analysis. The results of this research would have important values in the optimization design of cultivating components for energy and cost savings.

关键词： animal clawed toes soil cultivating component bionics optimization design energy-savings

Construction of a Bacterial Artificial Chromosome library of TM-1,a Standard line for Genetics and Genomics in Upland Cotton

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Journal of Integrative Plant Biology 2009年第1期51卷 107-112页

作者： Yan Hu Wang-Zhen guo Tian-Zhen Zhang National Key laboratory of Crop Genetics & Germplasm Enhancement Cotton Research Institute Nanjing Agricultural University Nanjing 210095 China

A bacterial artificial chromosome （BAC） library was constructed for Gossypium hirsutum acc. TM-1, a genetic and genomic standard line for Upland cotton. The library consists of 147 456 clones with an average insert size of 122.8 kb ranging from 97 to 240 kb. About 96.0% of the clones have inserts over 100 kb. Therefore, this library represents theoretically 7.4 haploid genome equivalents based on an AD genome size of 2 425 Mb. Clones were stored in 384 384- well plates and arrayed into multiplex pools for rapid and reliable library screening. BAC screening was carried out by four-round poiymerase chain reactions using 23 simple sequence repeats （SSR） markers, three sequence-related amplified polymorphism markers and one pair of primers for a gene associated with fiber development to test the quality of the library. Correspondingly, in total 92 positive BAC clones were identified with an average four positive clones per SSR marker, ranging from one to eight hits. Additionally, since these SSR markers have been localized to chromosome 12 （A12） and 26 （D12） according to the genetic map, these BAC clones are expected to serve as seeds for the physical mapping of these two homologous chromosomes, sequentially map-based cloning of quantitative trait loci or genes associated with important agronomic traits.

关键词： bacterial artificial chromosome library polymerase chain reaction screening simple sequence repeats markers TM-1 upland cotton.

Change Rules of Γ_2 Particles in Hot-dipped Zn-Ti Coating

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Journal of Iron and Steel Research International 2014年第3期21卷 396-402页

作者： Yan GUI Qiao-yu xU Yan-ling guo Guangzhou Panyu Polytechnic South China University of Technology

Hot-dip Zn-Ti galvanizing can restrain the excess growth of the coating which has better corrosion resist- ances than hot-dip pure Zn. The change rules of Г2 intermetallic compound in hot-dip Zn-Ti galvanizing is investiga ted by immersion time, titanium content and the slag test using scanning electron microscopy （SEM）, energy dis- persive spectroscopy （EDS） and x-ray diffraction （xRD）. And the mechanism of nucleation and growth of Г2 inter- metallic compound is analysed. The results show that, when adding 0. 05mass% titanium to the zinc bath, the Г2 particles form in the η layer, which nucleate by obtaining Ti atoms from the phase and Fe atoms from the dissol- ving ζ phase layer. Moreover, the more titanium is added into the bath, the more and bigger Гz particles appear. The Fz particles in the coatings grow up noticeably with prolonging the immersion time.

关键词： hot-dip galvanizing Zn-Ti alloy bath Г2 phase particle

Recognition of Human Promoter based on GMM and Rough Set 36

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Recognition of Human Promoter based on GMM and Rough Set

Finns-Kingdom RNA Silencing in Plant-Fungal Pathogen Interactions

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作者： guo Shuo YUAN De-cheng guo Wa Zhang Bochen li Jin-na Information Engineering College Shenyang University of Chemical Technology State Grid liaoning Electric Power Supply Co. Ltd Tieling Power Supply Company East China University of Science and Technology

ISBN: (纸本)9781538629185

Identifying Human promoter is the foundation for understanding gene regulation and the key point of large-scale function prediction. Although many algorithms have been proposed, they are rather complex with the performance still limited by low sensitivity and high false positives. In this paper, Gaussian Mixture Model is used to build the model of positional densities of oligonucleotides as the promoter features. Rough Set is applied for analysis the relationship of the binding sites occurence at same time and identify the human promoter sequence. Clustering algorithm which using the inverse of fuzzy likelihood function as the cluster distance is used to estimate the Gaussian Mixture Model optimal number and the parameters of sub-models. And least Square is used to calculate the mixing proportions. The optimal solution and efficient convergence are obtained. The features for building the predict model are not perfect, so Rough Set Theory is applied for building the promoter information table finding the relationship of the motifs at upstream and downstream of promoter sequence, at the mean time, to predict human promoter sequence. The simulation results show the accuracy of the prediction model is high.

关键词： Human promoter Gaussian Mixture Model fuzzy likelihood function cluster Rough Set

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Molecular Plant 2018年第2期11卷 235-244页

作者： Chenlei Hua Jian-Hua Zhao Hui-Shan guo State Key laboratory of Plant Genomics Institute of Microbiology Chinese Academy of Sciences 100101 Beijing China College of life Science University of the Chinese Academy of Sciences 100049 Beijing China

Fungal pathogens represent a major group of plant invaders that are the causative agents of many notorious plant diseases. large quantities of RNAs, especially small RNAs involved in gene silencing, have been found to transmit bidirectionally between fungal pathogens and their hosts. Although host-induced gene silencing （HIGS） technology has been developed and applied to protect crops from fungal infections, the mechanisms of RNA transmission, especially small RNAs regulating trans- kingdom RNA silencing in plant immunity, are largely unknown. In this review, we summarize and discuss recent important findings regarding trans-kingdom sRNAs and RNA silencing in plant-fungal pathogen interactions compared with the well-known RNAi mechanisms in plants and fungi. We focus on the interactions between plant and fungal pathogens with broad hosts, represented by the vascular pathogen Verticillium dahliae and non-vascular pathogen Botrytis cinerea, and discuss the known instances of natural RNAi transmission between fungal pathogens and host plants. Given that HIGS has been developed and recently applied in controlling Verticillium wilt diseases, we propose an ideal research system exploiting plant vasculature-Verticillium interaction to further study trans-kingdom RNA silencing.

关键词： fungal pathogens HIGS microRNA trans-kingdom RNAi small RNA Verticillium dahliae

Dual Spectroscopic Responses of Pyridinium Hemicyanine Dyes to Anions

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Chinese Journal of Chemistry 2011年第9期29卷 1975-1981页

作者： xie, Puhui guo, Fengqi Zhang, Dasheng Zhang, lei College of Sciences Henan Agricultural University Zhengzhou Henan 450002 China Department of Chemistry Zhengzhou University Zhengzhou Henan 450001 China

The absorption and fluorescence spectroscopic responses of three pyridinium hemicyanine dyes to anions F , Cl , Br , I-, H2P02, HS04 and OAc- were investigated. At lower concentrations of OAc- （less than 1 equiv.）, both the absorption and the fluorescence intensities of 1--3 were more effectively changed than F at iden- tical concentrations. At higher concentrations of OAc （more than 1 equiv.）, the interaction was opposite for each compound. 1H NMR results indicated the interaction between 1, 2 or 3 and F- proceeded through hydrogen bonding. The results showed that these dyes are promising to develop dual fluorescence and chromogenic chemo- sensors toward F- and OAc- according to the subtle difference in the affinity of F and OAc .

关键词： hemicyanine absorption spectra fluorescence spectra chemosensors anions

A Geometric Flow Approach for Region-based Image Segmentation-theoretical Analysis

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 65-76页

作者： Zhu-cui JING Juntao YE guo-liang xU School of Economics and Management Beijing Jim)tong University Beijing 100044 China Institute of Automation Chinese Academy of Sciences Beijing 100190 China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

In this paper, we analyze the well-posedness of an image segmentation model. The main idea of that segmentation model is to minimize one energy functional by evolving a given piecewise constant image towards the image to be segmented. The evolution is controlled by a serial of mappings, which can be represented by B-spline basis functions. The evolution terminates when the energy is below a given threshold. We prove that the correspondence between two images in the segmentation model is an injective and surjective mapping under appropriate conditions. We further prove that the solution of the segmentation model exists using the direct method in the calculus of variations. These results provide the theoretical support for that segmentation model.

关键词： l^2-gradient flow Bi-cubic B-spline direct method image segmentation

Dynamic-Response Analysis of the Branch System of a Utility Tunnel Subjected to Near-Fault and Far-Field Ground Motions in Different Input Mechanisms

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Computer Modeling in Engineering & Sciences 2022年第1期130卷 167-186页

作者： Yuhang Jin Endong guo Houli Wu Peilei Yan Institute of Engineering Mechanics China Earthquake AdministrationHarbin150080China Key laboratory of Earthquake Engineering and Engineering Vibration Harbin150080China

There are few studies on the dynamic-response mechanism of near-fault and far-field ground motions for large underground structures,especially for the branch joint of a utility tunnel(UT)and its internal *** on the theory of a 3D viscous-spring artificial boundary,this paper deduced the equivalent nodal force when a P wave and an SV wave were vertically incident at the same time and transformed the ground motion into an equivalent nodal force using a self-developed MATlAB program,which was applied to an ABAQUS finite element *** on near-fault and far-field groundmotions obtained fromtheNGA-WEST2 database,the dynamic responses of a utility tunnel and its internal pipeline in different inputmechanisms of near-fault and far-field groundmotions were compared according to bidirectional input and tridirectional input,***,the damage to the utility tunnel caused by the near-fault ground motion was stronger than that caused by the far-field ground motion,and the vertical ground motion of near-fault ground motion aggravated the damage to the utility *** addition,the joint dislocation of the upper and lower three-way joints of the pipeline in the branch systemunder the seismic action led to local stress *** general,the branch system of the utility tunnel had good seismic performance to resist the designed earthquake action and protect the internal pipeline fromdamage during the rare earthquake.

关键词： Dynamic response utility tunnel near-fault ground motion far-field ground motion earthquake input seismic design

Photoinduced Charge Transfer in MBB-PPV/C_(60) Composite Film

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Chinese Physics letters 2000年第11期17卷 829-831页

作者： guo li-Jun MA guo-Hong SHAN Fu-Kai MO Yu-Jun QIAN Shi-xiong Department of Physics Fudan UniversityShanghai 200433 Department of Physics Henan UniversityKaifeng 475001

The photoconductive properties of MBB-PPV/C_(60) composite films fabricated by the physical jet deposition(PJD)technique have been studied on the basis of the photoinduced charge transfer *** the photoex-citation,the transverse photoconductivity of the composite films is greatly enhanced by 4 orders of magnitude due to the efficient excitation transfer process from MBB-PPV(as donor)to C_(60)(as acceptor)occurring at the interface,the separation of charges and the existence of in-layer free *** results indicate that the conjugated polymer/fullerene composite films optimized by an appropriate configuration have potential applications in photoelectric devices and photonic fields.

关键词： composite V/C films