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Global Identification of Significantly Expressed Genes in Developing Endosperm of Rice by Expression Sequence Tags and cDNA Array Approaches

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Journal of Integrative Plant Biology 2008年第9期50卷 1078-1088页

作者： Qichao Tu haitao dong Haigen Yao Yongqi Fang Cheng'en Dai Hongmei Luo Jian Yao dong Zhao Debao Li Bioinformatics and Gene Network Research Group Institute of Biotechnology Zhejiang University Hangzhou 310029 China Jiaxing Academy of Agricultural Science Jiaxing 314016 China College of Life and Environmental Sciences Hangzhou Normal University Hangzhou 310036 China

Rice endosperm plays a very important role in seedling germination and determines the qualities of rice grain. Although studies on specific gene categories in endosperm have been carried out, global view of gene expression at a transcription level In rice endosperm Is still limited. To gain a better understanding of the global and tissue-specific gene expression profiles In rice endosperm, a cDNA library from rice endosperm of immature seeds was sequenced. A cDNA array was constructed based on the tentative unique transcripts derived from expression sequence tag （EST） assembling results and then hybridized with cDNAs from five different tissues or organs including endosperm, embryo, leaf, stem and root of rice. Significant redundancy was found for genes encoding prolamin, glutelin, allergen, and starch synthesis proteins, accounting for ~34% of the total ESTs obtained. The cDNA array revealed 87 significantly expressed genes In endosperm compared with the other four organs or tissues. These genes included 13 prolamin family proteins, 17 glutelin family proteins, 12 binding proteins, nine catalytic proteins and four ribosomal proteins, indicating a complicated biological processing in rice endosperm. In addition, Northern verification of 1,4-alpha-glucan branching enzyme detected two isoforms in rice endosperm, the larger one of which only existed in endosperm.

关键词： cDNA array endosperm expression profile expression sequence tag rice (Oryza sativa)

Enhancing Site Style Tree Construction Algorithm

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Wuhan University Journal of Natural Sciences 2009年第2期14卷 129-133页

作者： ZHU Fuxi GONG Changsheng YAO haitao dong Wenyong School of Computer Wuhan University Wuhan 430072Hubei China

The World Wide Web has become a global information service center with a vast amount of news, advertisements, product and service information, and disparate information from diversi- fied sources. However, only a small portion of information is truly relevant and useful to the users who are seeking information on specific topics. In this paper, common relations among nodes are taken into consideration when constructing site style tree, and a new node type is introduced. Experimental results show that the proposed algorithm has higher precision and recall.

关键词： site style tree Web mining noise clean

The Construction of Linux System and Network Programming Course to Develop Engineering Ability

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计算机教育 2020年第12期 107-113页

作者： haitao dong GuoBing Ma School of Information and Control Engineering Qingdao University of TechnologyQingdao 266520China

To meet society’s needs for undergraduate students to have engineering skills and to develop students’ability to operate Linux and engage in network software development,this paper proposes the construction of a new specialized course for network engineering major--Linux system and network *** paper analyzes the course’s advantages,presents the contents of this course,designs a series of teaching methods aimed at improving students’engineering ability,proposes a course assessment method that will encourage students to practice,lists the development requirements for an examination software designed for this course,and finally,presents the results of our practice in teaching this course.

关键词： Linux teaching Linux network programming development of engineering ability course construction.

Gene expression profiling under different photoperiod/temperature conditions in a photoperiod-/thermo-sensitive genic male sterile line of rice(Oryza sativa L.)

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Chinese Science Bulletin 2006年第2期51卷 175-181页

作者： GUO Xiaoqin dong haitao ZHENG Kangle LUO Hongmei TAN Xuelin FANG Yongqi WANG Yanqin DENG Ye DAI Chengen LOU Yichun SHAO Jing SHI Wenqin ZHAO dong LI Debao Bioinformatics and Gene Network Research Group Zhejiang University Hangzhou 310029 China National Center for Rice Improvement China National Rice Research Institute Hangzhou 310006 China College of Life Sciences Hangzhou Teachers College Hangzhou 310012 China Rice Research Institute Yunnan Agricultural University Kunming 650201 China

Peiai 64S is a photoperiod- and thermo- sensitive genic male sterile (PTSGMS) line of rice, which is male sterile at long day/high temperature and partial fertile at short day/low temperature. A cDNA array representing 3328 unique rice genes was used to profile the gene expression patterns in the young panicles of Peiai 64S under these two condi- tions. The statistical data showed that up to 14.60% of genes exhibited up-or down-regulated expressions in the plants at long day/high temperature compared with plants at short day/low temperature. Only four genes were up-regulated while 482 genes down-regulated. Real-time PCR with all the up-regulated and 9 randomly selected down-regulated genes confirmed the differential expressions detected by the array, indicating that the constructed cDNA array is reliable. These differently expressed genes participated in almost all cell biological responses. Analysis of up- and down-regulated genes revealed distinctive changes between the mRNA abundances of MMK1 and MMK2, both of which are analogs ofMAPK, and significant down-regulation of several transcription factors. It was suggested that changes that occurred in the MAPK signal transduction path- way might disturb the transcription control necessary for morphogenesis of pollens and corresponding phys- iological functions.

关键词：水稻光周期温度热敏感性雄性不育基因基因表达信号转导

用虚拟黏性法构造Navier-Stokes方程黏性项的隐式格式

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航空学报 2015年第7期36卷 2186-2196页

作者：董海涛刘丁松北京航空航天大学航空科学与工程学院北京100191

提出的虚拟黏性法是一种关于Navier-Stokes方程黏性项(黏性应力项和传热项)的隐式新方法。通过引入虚拟时间和虚拟黏性项,将隐式格式的构造大大简化,从而避免了大型复杂隐式差分方程组的常规求解。在虚拟时间推进过程中所需求解的方程... 详细信息

提出的虚拟黏性法是一种关于Navier-Stokes方程黏性项(黏性应力项和传热项)的隐式新方法。通过引入虚拟时间和虚拟黏性项,将隐式格式的构造大大简化,从而避免了大型复杂隐式差分方程组的常规求解。在虚拟时间推进过程中所需求解的方程组的系数矩阵是一个三对角矩阵,它具有计算简单且计算量小的优点。用模型方程和NavierStokes方程进行了数值仿真,研究各种参数对计算的影响,并在精度和效率上与显式方法进行比较,证实了算法的正确性和优势。最后分析了本文格式的适用范围。

关键词： Navier-Stokes方程算子分裂隐式格式虚拟黏性虚拟时间

Euler方程的分裂型通量分裂双时间步隐式方法

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北京航空航天大学学报 2015年第5期41卷 776-785页

作者：董海涛陈喆刘福军北京航空航天大学航空科学与工程学院北京100191

传统隐式方法有格式复杂、计算量大等缺点,在Euler方程的差分离散过程中,利用算子分裂思想,结合通量分裂法、双时间步法等隐式离散方法,构造了一种更简单的分裂型隐式计算方法.通过对典型空气动力学问题的计算,检验了该方法的有效性和... 详细信息

传统隐式方法有格式复杂、计算量大等缺点,在Euler方程的差分离散过程中,利用算子分裂思想,结合通量分裂法、双时间步法等隐式离散方法,构造了一种更简单的分裂型隐式计算方法.通过对典型空气动力学问题的计算,检验了该方法的有效性和可靠性,并对其性能做了具体讨论.该方法具有稳定性好、时间步长约束小等隐式格式的普遍优点,同时具有格式简单、程序易实现等优点;避免了传统隐式方法单步推进时的方程组常规求解及矩阵求逆过程,计算量小;比LU-SGS方法收敛速度快.

关键词： Euler方程算子分裂通量分裂双时间步隐式方法

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熔融沉积快速成型的工艺分析

制造技术与机床 2013年第10期 96-98页

作者：董海涛山西机电职业技术学院山西长治046011

对熔融沉积快速成型工艺原理进行介绍,分析了成型的工艺特点;以MEM300成型机为例,对熔融沉积双喷头工艺装备进行研究,论述了设计支撑的原因和支撑的种类;详细说明了FDM的成型工艺过程,以垂直方向高的模型——可乐瓶成型为例,比较分析4... 详细信息

对熔融沉积快速成型工艺原理进行介绍,分析了成型的工艺特点;以MEM300成型机为例,对熔融沉积双喷头工艺装备进行研究,论述了设计支撑的原因和支撑的种类;详细说明了FDM的成型工艺过程,以垂直方向高的模型——可乐瓶成型为例,比较分析4种成型方向布置方案,研究总结出几条成型方向原则,这些原则有利于提高成型质量和缩短成型时间;快速成型技术已经成为现代制造业的热点和发展方向。

关键词：快速成型熔融沉积支撑分层成型方向

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注塑模优化设计理论的研究与应用

塑料科技 2015年第10期43卷 95-98页

作者：董海涛山西机电职业技术学院山西长治046011

注塑成型是塑料制品生产中的重要工艺,因此关于注塑模优化设计的研究具有重要意义。为提升注塑模工艺技术水准、完善注塑模优化设计理论、强化注塑模优化的实际应用,本研究就注塑模填充、壁厚优化、浇口位置优化、浇注系统优化等方面进... 详细信息

注塑成型是塑料制品生产中的重要工艺,因此关于注塑模优化设计的研究具有重要意义。为提升注塑模工艺技术水准、完善注塑模优化设计理论、强化注塑模优化的实际应用,本研究就注塑模填充、壁厚优化、浇口位置优化、浇注系统优化等方面进行了研究。

关键词：注塑模注塑成型优化设计应用分析

SiC颗粒增强2A02Al基复合材料组织和性能的研究

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粉末冶金工业 2022年第3期32卷 91-95页

作者：董海涛山西机电职业技术学院山西长治046011

采用热压烧结工艺制备了30%SiCp/2A02Al复合材料,对烧结试样进行热挤压变形,利用OM、SEM和TEM观察了复合材料微观组织和断口形貌,并检测了密度和力学性能。结果表明:SiCp/2A02Al复合材料的基体与增强体界面结合良好,界面清晰平滑;热挤压... 详细信息

采用热压烧结工艺制备了30%SiCp/2A02Al复合材料,对烧结试样进行热挤压变形,利用OM、SEM和TEM观察了复合材料微观组织和断口形貌,并检测了密度和力学性能。结果表明:SiCp/2A02Al复合材料的基体与增强体界面结合良好,界面清晰平滑;热挤压后SiC颗粒偏聚减少,SiC均匀分布在基体中,在基体内生成了高密度位错和亚晶;复合材料的致密度增加,力学性能显著提高;热挤压试样经过时效处理后在基体内生成了圆盘状的沉淀析出相(Al_(2)Cu相)。

关键词： SiCp/2A02Al复合材料热挤压力学性能显微组织时效析出