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DC dielectrophoresis separation of marine algae and particles in a microfluidic chip

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science china Chemistry 2012年第4期55卷 524-530页

作者： SONG YongXin1, YANG JianDong1, SHI XiaoFei4, JIANG Hai3, WU YanBin1, pENG ran1, WANG Qi5, GONG Ning2, pAN XinXiang1, SUN YeQing2 & LI DongQing1,31dep.r.ment of Marine Engineering, Dalian Maritime university, Dalian 116026, china 2Institute of Environmental Systems Biology, Dalian Maritime university, Dalian 116026, china 3dep.r.ment of Mechanical and Mechatronics Engineering, university of Waterloo, Waterloo, ON, N2L 3G1, Canada 4College of Information science and technology, Dalian Maritime university, Dalian 116026, china 5dep.r.ment of respiratory Medicine, the Second Hospital Affiliated to Dalian Medical university, Dalian 116026, china 1. dep.r.ment of Marine Engineering Dalian Maritime University Dalian 116026 China4. College of Information Science and Technology Dalian Maritime University Dalian 116026 China3. Department of Mechanical and Mechatronics Engineering University of Waterloo Waterloo ON N2L 3G1 Canada5. Department of Respiratory Medicine the Second Hospital Affiliated to Dalian Medical University Dalian 116026 China2. Institute of Environmental Systems Biology Dalian Maritime University Dalian 116026 China

This paper reports a microfluidic method of continuous separation of marine algae and particles by DC dielectrophoresis. The locally non-uniform electric field is generated by an insulating pDMS triangle hurdle fabricated within a pDMS microchannel. Both the particles and algae are subject to negative dep forces at the hurdle where the gradient of local electric-field strength is the strongest. The dep force acting on the particle or the algae depends on particles' or algae's volume, shape and dielectric properties. Thus the moving particles and algae will be repelled to different streamlines when passing the hurdle. In this way, combined with the electroosmotic flow, continuous separation of algae of two different sizes, and continuous separation of polystyrene particles and algae with similar volume but different shape were achieved. This first demonstration of DC dep separation of polystyrene particles and algae with similar sizes illustrates the great influence of dielectric properties on particle separation and potentials for sample pretreatment.

关键词： DC dielectrophoresis – marine algae – particle – microfluidic chip – permittivity difference

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基于决策图的Web数据库访问优化策略

计算机工程与应用 2004年第8期40卷 181-183页

作者：胡虚怀郑若忠湖南理工学院计算机系岳阳414000 国防科技大学计算机学院长沙410073

文章提出了一种用来解决Web数据库访问优化问题的决策方法的新应用。这种基于图形结构的优化方法借助了香农信息论手段,能够减少数据访问的时间,实现对大型数据库的快速查询,降低数据库的设计成本。

关键词： Web数据库优化决策图信息论熵

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C^2连续近似弧长参数化曲线

数值计算与计算机应用 2003年第2期24卷 144-148页

作者：方逵谭建荣长沙大学计算机科学与技术系浙江大学 310027

This paper presents a method for nearly arc-length parameterization based on the rational cubic function. The arc-length function of parametric curve is monotonic increasing, the monotonity preserving rational cubic approximation for the arc-length function is derived. The resulting nearly arc-length parametrized curve is C2-continuous and interpolates a set of points of original curve. At each of the points, nearly arc-length parametrized curve is accurate. Finally, an example illustrate that the method is very efficient.

关键词：弧长参数化参数曲线 C^2保单调插值 CAD 样条曲线数值积分

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基于神经网络的方案加权平均值计算

计算机工程与应用 2003年第18期39卷 90-91,126页

作者：胡军管春北京理工大学计算机科学工程系北京100081 南昌大学计算机科学工程系南昌330029

在Delphi法数据统计处理过程中,成员权值主要根据成员的经历、职务、年龄和自我评定等情况来确定,易导致方案加权平均值及方差计算不准确,大大影响Delphi法的精度和效率。为提高Delphi法的精度和效率,论文提出了基于Bp神经网络的方案加... 详细信息

在Delphi法数据统计处理过程中,成员权值主要根据成员的经历、职务、年龄和自我评定等情况来确定,易导致方案加权平均值及方差计算不准确,大大影响Delphi法的精度和效率。为提高Delphi法的精度和效率,论文提出了基于Bp神经网络的方案加权平均值计算模型,使成员权值分配与其决策预测结果直接相关,减少了人为不正确因素对权值分配的影响,使权值分配较为客观,并且权值分配还具有动态的自学习功能,具有一定的智能性。该计算模型被成功应用于股票上市公司经营业绩综合评价排序。

关键词：人工神经网络 Delphi方法计算模型

Hale中立型延迟微分方程的耗散性:新的准则及其应用

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应用数学学报 2019年第4期42卷 564-576页

作者：王晚生黄艺王为饶婷长沙理工大学数学与统计学院长沙410114 上海师范大学数学系上海200234

本文研究由Hale型非线性中立型延迟微分方程(HNDDEs)生成的耗散动力系统的耗散性,其与不变测度紧密相关.利用广义的Halanay不等式,给出了非线性非自治HNDDEs-些新的、有用的耗散准则.本文详细讨论了两个具体的动力系统:一是由传输线问... 详细信息

本文研究由Hale型非线性中立型延迟微分方程(HNDDEs)生成的耗散动力系统的耗散性,其与不变测度紧密相关.利用广义的Halanay不等式,给出了非线性非自治HNDDEs-些新的、有用的耗散准则.本文详细讨论了两个具体的动力系统:一是由传输线问题所产生的模型,二是非线性Nicholson丽蝇模型.

关键词： Hale中立型延迟微分方程耗散性 Halanay不等式耗散动力系统无损传输线模型 Nicholson丽蝇模型

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水力割缝开采低渗透煤层气应力场数值模拟

天然气工业 2004年第10期24卷 93-95,i024页

作者：唐巨鹏李成全潘一山辽宁工程技术大学力学与工程科学系

文章首次基于Ansys有限元分析软件对水力割缝技术开采低渗透煤储层煤层气进行了数值模拟的计算研究,指出地应力是煤层气运移的重要影响因素,给出了煤层气赋存和运移特征及地应力对煤层气运移的作用机理,建立了煤层气开采水力割缝平面应... 详细信息

文章首次基于Ansys有限元分析软件对水力割缝技术开采低渗透煤储层煤层气进行了数值模拟的计算研究,指出地应力是煤层气运移的重要影响因素,给出了煤层气赋存和运移特征及地应力对煤层气运移的作用机理,建立了煤层气开采水力割缝平面应变有限元模型,得到了钻井前后、水力割缝前后近井地带的地应力场变化规律及其影响范围。钻井后近井地带应力平均降低60%,但井口周边产生了应力集中区,应力场以井孔为中心向井身周边呈辐射状向外递减,应力降影响范围为300～450mm。水力割缝后井周区域应力场变化显著,近井地带应力平均降低84.5%,且沿两侧割缝末端连线方向应力降影响最为明显,影响范围以此向外辐射达3000mm,为钻井孔径的20倍,同时在割缝末端产生了应力集中区,并向背离割缝方向扩散,使得沿割缝方向产生大量裂缝,从而打通割理和裂隙,缩短渗透路径,继而提高煤层气产量。数值模拟结果表明,水力割缝技术可达到使近井地带充分卸压的目的。在现场实践中,此方法对利用定量化指标评估水力割缝效果具有十分重要的指导意义。

关键词：近井地带水力割缝技术低渗透钻井井身井口煤层气应力降区域应力场煤储层

prELIMINArY STUDY ON THE ASSOCIATION OF HOrMONE SENSITIVE LIpASE GENE pOLYMOrpHISM WITH pIG pErFOrMANCE

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PRELIMINARY STUDY ON THE ASSOCIATION OF HORMONE SENSITIVE LI...

Characterization of Function of Three Domains in Dishevelled-1: dep Domain is responsible for Membrane Translocation of Dishevelled-1

面向21世纪的动物科学与动物医学国际研讨会

作者： WUZhen-Fang XIONG Yuan-Zhu I.Harbitz Deng Chang-Yan JIANG Si-Wen( College of Animal science, Huazhong Agricultural university, Wuhan, 430070, china College of Animal science, South of china Agricultural university, Guangzhou, 510640, china Norwegian School of Veterinary science., p.O. Box 8146dep. N-0033 Olso, Norway)

＜正＞Hormone sensitive iipase （HSL） is a key enzyme in fat metabolism. The polymorphism of the pig HSL gene is studied in this paper. The SSCp （Single Strand Conformational polymorphism） is found in the HSL gene Exon 8. It showed three genotypes （MM. MN. NN）, fat-type pig breeds the Meishan and Tongcheng pigs have more allele M, with frequencies of 0.690M and 0.740M, respectively;however, lean-type pig breeds Landrace and the Large white pigs have more allele N, with frequencies of 0.847 N and 0.845 N, respectively. pCr fragments representing HSL genotypes MM and NN are sequenced. Two A→G transitions were detected, and it resulted in corresponding changes of amino acid （Asn→Asp and Glu→Gly） in the HSL protein, respectively. Also significant association were found between SSCp of the porcine HSL gene and backfat depth in Meishan × the large white pig population. We think the HSL gene may be considered as a candidate gene for fatness in pigs.

关键词： hormone sensitive lipase pig SSCp

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Cell research 2004年第4期14卷 324-330页

作者： Wei Jun pAN, Shu Zhao pANG, Tao HUANG, Hui Yun GUO, Dianqing WU, Lin LI Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Graduate School of the Chinese Academy of sciences, 320 Yueyang rd, Shanghai 200031 College of Life science, Jilin university, Changchun 130061, china. dep.r.ment of Genetics and Developmental Biology, university of Connecticut Health Center, Farmington, Connecticut 06030, USA. 1Laboratory of Molecular Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences 320 Yueyang Rd Shanghai 200031. 2College of Life science Jilin University Changchun 130061 China. 1Laboratory of Molecular Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences 320 Yueyang Rd Shanghai 200031. 2College of Life science Jilin University Changchun 130061 China. 3dep.r.ment of Genetics and Developmental Biology University of Connecticut Health Center Farmington Connecticut 06030 USA. 1Laboratory of Molecular Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences 320 Yueyang Rd Shanghai 200031.

Wnt signaling plays an important role in embryogenesis and tumorgenesis. Although the mechanism about how Wnts transduce their signaling from receptor frizzled (Fz) to cytosol has not been understood, dishevelled (Dvl) protein was considered as the intersection of Wnt signal traffic. In this study, we characterized the function of three domains (DIX, pDZ and dep) of Dvl-1 in canonical Wnt signal transduction and Dvl-1 membrane translocation. It was found both DIX and dep domain were sufficient to block Wnt-3a-induced LEF-1 transcriptional activity and free cytosol β-catenin accumulation; whereas pDZ domain and a functional mutant form of dep domain (dep-KM) had no effect on canonical Wnt signaling. In addition, when cotransfected with Fz-7, dep domain, but not DIX, pDZ or dep-KM, translocated and co-localized with Fz-7 to the plasma membrane, which was similar to Dvl-1. Furthermore, it was dep domain that could block Fz-7-induced membrane translocation of Dvl-1 via a possible competitive mechanism. Thes

关键词： Wnt frizzled-7 dishevelled DIX pDZ dep membrane translocation signal transduction

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单变量凸函数所蕴含的基本不等式

四川工业学院学报 2001年第4期20卷 60-61,65页

作者：刘鹏惠四川工业学院计算机科学与工程系四川成都610039

凸函数是以不等式为特征性质的一类函数 ,它与数学分析中一些常用不等式的建立存在有机的联系。而这些常用不等式直接证明的方法虽多 ,但都不容易。

关键词：凸函数导数不等式数学分析数学归纳法