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Prediction of eukaryotic gene structures based on multilevel optimization

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Chinese Science Bulletin 2004年第4期49卷 321-328页

作者： ZHOUYanhong YANGLei wanghui LUFeng WANHonghui SchoolofComputerScienceandTechnology HuazhongUniversityofScienceandTechnologyWuhan430074China SchoolofLifeScienceandTechnology HuazhongUniversityofScienceandTechnologyWuhan430074China LaboratoryofBioinformatics MarylandInstituteofDynamicGenomicsSilverSpringMD20906USA

Computational gene structure prediction, which is valuable for finding new genes and understanding the composition of genomes, plays a very important role in various kinds of genome projects. For eukaryotic gene structures, however, the prediction accuracy of existing methods is still limited. This paper presents a method of pre-dicting eukaryotic gene structures based on multilevel opti-mization. The complicated problem of predicting gene structure in eukaryotic DNA sequence containing multiple genes can be decomposed into a series of sub-problems at several levels with decreasing complexity, including the gene level (single-exon gene, multi-exon gene), the element level (exon, intron, etc.), and the feature level (functional site sig-nals, codon usage preference, etc.). On the basis of this de-composition, a multilevel model for the prediction of complex gene structures is created by a multilevel optimization proc-ess, in which the models dealing with sub-problems at low complexity level are first optimized respectively, and then optimally combined together to form models for those sub-problems at higher complexity level. Based on the multi-level model, a dynamic programming algorithm is designed to search for optimal gene structures from DNA sequences, and a new program GeneKey (1.0) for the prediction of eu-karyotic gene structures is developed. Testing results with widely used datasets demonstrate that the prediction accura-cies of GeneKey (1.0) at the nucleotide level, exon level and gene level are all higher than that of the well known program GENSCAN. A web server of GeneKey(1.0) is available at http://***.

关键词：真核基因结构预测脱氧核糖核酸蛋白质编码区基因工程

Motion Planning for Industrial Robots Based on Task Process Decomposition

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Chinese Journal of Mechanical Engineering 2010年第2期23卷 135-141页

作者： BU wanghui LIU Zhenyu TAN Jianrong State Key Laboratory of CAD ＆ CG Zhejiang University Hangzhou 310027 China

The existing research of the industrial robotic motion planning mainly focuses on the trajectory planning and the path planning, which aim at obtaining a minimum-time trajectory and finding an obstacle-free path respectively. In the trajectory planning, the jerks of robotic joints are usually not considered, so the smoothness of the robotic motion cannot be ensured. In the path planning, the complex spatial curves generally cannot be tracked easily, and it needs the fussy teach-and-playback operation. In this paper, based on the different constraint characteristic of the variable motion phases in the practical robotic task, the complicated task is decomposed into two kinds of sub processes, which are the free motion process and the constrained motion process. In the free motion process, the kinematic models of quasi trapezoidal waveform and quasi triangular waveform are proposed with the dynamic limits of maximum velocities, accelerations and jerks of robotic joints, so the minimum-time trajectory can be obtained with the motion smoothness. In the constrained motion process, the mathematical presentation of the task paths is extracted from the CAD models of the workpieces, so the complex spatial curves can be tracked autonomously without much teaching operation. In addition to the theoretical research, a robotic virtual prototyping system is also developed for the industrial arc welding production. The proposed research ensures the robotic motion smoothness, enhances the ability for tracking the complex spatial curves, and improves the quality and efficiency of the robotic motion planning.

关键词： robotic manipulator trajectory planning path planning virtual prototyping

Streptomyces avermitilis from marine

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Journal of Environmental Sciences 2005年第1期17卷 123-125页

作者： XIONGLi-xia LIJian-zhong wanghui-li ResearchCenterforEeo-EnvironmentalSciences ChineseAcademyofSciencesBeijing100085China

The insecticidal strain 173 was isolated from marine source and its activity was explored by the bioassay of brine shrimp and Helicoverpa armigera . Based on morphological, physiological and molecular properties, the insecticidal strain 173 was identified as Streptomycetes avermitilis , which is the best insecticidal microorganism found in the terrestrial environment. The taxonomy of the strain 173, insecticidal spectrum and properties of the corresponding insecticidal antibiotics are reported.

关键词： insecticidal microorganism marine taxonomy Streptomyces avermitilis

SPATIAL ANALYSIS OF SOIL EROSION AND NON-POINT SOURCE POLLUTION BASED ON GIS IN ERLONG LAKE WATERSHED, JILIN PROVINCE

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Chinese Geographical Science 2004年第4期14卷 355-360页

作者： WANGNing ZHANGHong-yan wanghui-lian ZHANGZheng-xiang DepartmentofEnvironmentalScience NortheastNormalUniversityChangchun130024P.R.China LaboratoryofGeographicInformationProject NortheastNormalUniversityChangchun130024P.R.China

Data collection, factor composition, nappe analysis and integrative simulation of natural geographical factors in Erlong Lake watershed have been carried out based on GIS. The risk areas where non-point source pollution may occur were compartmentalized and assessed, and the total soil erosion and the runoffs of N and P with rainfall in this valley were worked out by experiment and GIS mapping. The study indicated that the main type of soil erosion was moderate (erosion modulus is 1000-2500t/(km(2).a)) at present, and the intense erosion areas are located in dry land with variable slope east of the lake and the middle-south parts of steep slope mountainous region (erosion modulus is more than 5000t/(km(2).a)). Though the area is small, it should be paid attention to. The trend of non-point source pollution (NSP) of nitrogen and phosphorus loss was corresponded with the soil erosion. Spatial distribution and the reasons of the distribution difference have been presented and it was emphasized that the human activities among the influence factors was the most important. It surely offers a scientific basis to control and prevent non-point source pollution in the watershed.

关键词： soil erosion non-point source pollution Erlong Lake Geographic Information System (GIS)

SINGULAR PERTURBATION FOR REACTION DIFFUSION EQUATIONS

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Applied Mathematics(A Journal of Chinese Universities) 2003年第3期18卷 251-257页

作者： MoJiaqi wanghui ZhuJiang Dept.ofMath. HuzhouTeachersCollegeHuzhou313000China. CommitteeofNationalNaturalSciencesFoundationofChina Beijing100085China. ICEES InstituteofAtmosphericPhysicsChineseAcademyofSciencesBeijing100029China.

The singularly perturbed initial boundary value problems for reaction diffusion equations are *** suitable conditions and by using the theory of differential inequality,the asymptotic behavior of solution for initial ... 详细信息

关键词： nonlinear reaction diffusion equation singular perturbation

Soil-Column Test on Aniline Degradation in Riverbank Filtration under Denitrification Conditions

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Journal of China University of Geosciences 2005年第2期16卷 183-188页

作者： WuYaoguo wanghui ZhangWencun SunWeijian Department of Applied Chemistry Northwestern Polytechnical UniversityXi＇an710072China

Drinking water is at risk from aniline pollution and thus aniline degradation and its mechanism have received much attention. In this paper, a soil column, including sediments and aquifer media, was collected from the Weihe riverbed and its bank, and used to research the characteristics of aniline degradation in the riverbank filtration process under denitrification conditions. The results indicate that all aniline could be degraded by the habituated indigenous microbes, and even mostly mineralized under denitrification conditions, but with a long lag phase. Some aniline degradation must involve deamination, while the majority undergoes covalent binding with humic substances to form complexes, and the complexes are easily degraded and even mineralized. During the degradation no intermediates were harmful to denitrifiers. Therefore, under denitrifaction conditions, aniline is degraded in RBF, and up to now aniline has not been monitored in the groundwater along the polluted river. During the 153 d testing process, the nitrate-nitrogen concentration was about 23.0 mg/L, and aniline concentrations were 40, 80 or 400 mg/L at 0-74 d, 75-105 d and 106-153 d respectively in infiltrating water. Indigenous microbes pass a lag period of 37 d, and grow on aniline as the source of carbon in the RBF under denitrification conditions. Aniline concentration in leachate was lower than the detected limits, so its removal rate was 100 %. Total organic carbon (TOC) removal rates were 97.99 %, 91.39 % and 75.30 % for 40, 80 and 400 mg/L aniline concentrations respectively, based on TOC monitored in infiltrating water and leachate.

关键词： denitrification conditions aniline riverbank filtration anaerobic bio-translation

SEM analysis of the changes of carbon layer structure of mesocarbon microbeads heat-treated at different temperatures

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Chinese Science Bulletin 2004年第11期49卷 1105-1110页

作者： LITongqi WANGChengyang LIUXiujun ZHENGJiaming wanghui KeyLaboratoryforGreenChemicalTechnologyofMinistryofEducation SchoolofChemicalEngineeringandTechnology.TianjinUniversity.Tianjin300072China AnalysisCenter TianjinUniversityTianjin300072.China

Mesocarbon microbeads (MCMB) with narrow size distribution, excellent sphericity and no obvious conglu-tination have been prepared with a coal tar pitch containing quinoline insolubles (QI) as the raw material. Optical mi-croscopy and scanning electron microscopy (SEM) are used to examine the structure of the MCMB. It has been found that SEM technique shows the structural information of MCMB clearly in the form of micrographs even when the structure of MCMB is complex, while the optical technique is useful for analysis of the regular structure of the mesophase spheres but cannot be effectively used to analyze either the complex structure of the green MCMB or the structures of the further heat-treated ones at different temperatures. Ac-cording to the characteristics of the carbon layers, the struc-tures of the as-prepared MCMB in the present experiment could be classified as (1) Parallel Layer type structure and (2) Bent Layer type structure with the carbon layers gathering at one or two points in the MCMB. In the experiments, SEM is also utilized to investigate the structures of MCMB that are heat-treated at different temperatures. It has been found that the MCMB without any further heat-treatment show no layered-carbons, while the ones heat-treated at temperature higher than 1000℃ exhibit obvious layered carbons across their sections. When increasing the heat-treatment tempera-ture, the carbon layers become thinner and flatter.

关键词：扫描电子显微镜热处理缺陷结构球墨材料中碳微球

QUANTITATIVE STUDY OF SOIL EROSION AND ELEMENT RUN-OFF IN THE SONGHUA LAKE VALLEY

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Chinese Geographical Science 2003年第3期13卷 238-241页

作者： WANGNing ZHUYan-ming wanghui-lian DepartmentofEnvironmentalScience NortheastNormalUniversityChtmgchun130024P.R.China NortheastInstituteofGeographyandAgriculturalEcology ChineseAcademyofSciencesChangchun130012P.R.China

Under the condition of different precipitation intensities, different gradients, different land-use types and different vegetation coverage, the soil erosion and transference of element (or pollutant) are studied by simulating and analyzing the surface run-off of experimental plots in the catchment area of Songhua Lake, with an area of about 43 370.8km2. And the influencing factors that produce the spatial difference are analyzed and assessed. It is put forward that the irrational land utilization is the reason of soil erosion and pollutant run-off. The gradient of farmland, the growing season of vegetation and the vegetation coverage are chiefly restricting factors that lead to the soil erosion and pollutant run-off. This study can provide the fundamental data for comprehensive planning and harnessing of the non-point source pollution in the valley.

关键词： soil erosion pollutant run-off land-use type vegetation coverage

gt-C3N4 coordinated single atom as an efficient electrocatalyst for nitrogen reduction reaction

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Nano Research 2019年第5期12卷 1181-1186页

作者： Lifu Zhang wanghui Zhao Wenhua Zhang Jing Chen Zhenpeng Hu School of Physics Nankai UniversityTianjin 300071China Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy Conversion and Synergetic Innovation Centre of Quantum Information & Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The electrochemical reduction of nitrogen to ammonia is a promising way to produce ammonia at mild *** design and preparation of an efficient catalyst with high ammonia selectivity is critical for the real *** this work,a series of transition metal (TM =Sc,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,Y,Zr,Nb,Mo,Tc,Ru,Rh,Pd,Ag,and Cd) atoms supported by gt-C3N4 (TM/gt-C3N4) are investigated as electrocatalysts for the nitrogen reduction reaction (NRR) based on density functional *** is found that Mo/gt-C3N4 with a limiting potential of-0.82 V is the best catalyst for standing-on adsorbed N2 *** for lying-on adsorbed N2 cases,V/gt-C3N4 with a limiting potential of-0.79 V is berer than other *** is believed that this work provides several promising candidates for the non-noble metal electrocatalysts for NRR at mild condition.

关键词： nitrogen reduction reaction single-atom catalyst first-principles calculation Gibbs free energy