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Lie Point Symmetries of Differential-Difference Equations

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Communications in Theoretical Physics 2004年第5期41卷 645-648页

作者： DING Wei~1 TANG Xiao-Yan~(2,3. 1 Department of Applied Mathematics,Shanghai Jiao Tong University,Shanghai 20003.,China2 Department of Physics,Shanghai Jiao Tong University,Shanghai 20003.,China3.State Key Laboratory of Scientific and Engineering Computing,Institute of Computational Mathematics and Scientific Engineering Computing,Academy of Mathematics and System Sciences,the Chinese Academy of Sciences,P.O.Box 2719,Beijing 100080,China Department of Applied Mathematics Shanghai Jiao Tong University Shanghai 200030 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific Engineering Computing Academy of Mathematics and System Sciences the Chinese Academy of Sciences P.O. Box 2719 Beijing 100080 China

In this paper,the classical Lie group approach is extended to find some Lie point symmetries of differential-difference *** reveals that the obtained Lie point symmetries can constitute a Kac-Moody-Virasoro algebra.

关键词： Lie point symmetry differential-difference equation Kac Moody-Virasoro algebra

Anisotropic characteristics of electrical responses of fractured reservoir with multiple sets of fractures

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Petroleum Science 2009年第2期6卷 127-138页

作者： Shen Jinsong Su Benyu Guo Naichuan Department of Geophysics School of Resource and Information Technology China University of Petroleum Beijing 102249 China Key Laboratory of CNPC Geophysical Exploration China University of Petroleum Beijing 102249 China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

In fractured reservoirs, the fractures not but also form the main flow channels which connect productivity of reservoirs. However, because of the only provide the storage space for hydrocarbons, the pores of the matrix, so fractures dominate the heterogeneity and randomness of the distribution of fractures, exploration and evaluation of fractured reservoirs is still one of the most difficult problems in the oil industry. In recent years, seismic anisotropy has been applied to the assessment of fractured formations, whereas electrical anisotropy which is more intense in fractured formations than seismic anisotropy has not been studied or used so extensively. In this study, fractured reservoir models which considered multiple sets of fractures with smooth and partly closed, rough surfaces were established based on the fractures and pore network, and the vertical and horizontal electrical resistivities were derived as a function of the matrix and fracture porosities according to Ohm＇s law. By using the anisotropic resistivity equations, variations of the electrical anisotropy of three types of fractured models under the conditions of free pressure and confining pressure were analyzed through the variations of the exerted pressure, matrix porosity, fracture aperture and formation water resistivity. The differences of the vertical and horizontal resistivities and the anisotropy between the connected and non-connected fractures were also analyzed. It is known from the simulated results that an increase of the confining pressure causes a decrease of electrical anisotropy because of the elasticity of the closed fractures and the decrease of the fracture aperture. For a fixed fracture porosity, the higher the matrix porosity, the weaker the electrical anisotropy in the rock formation.

关键词： Fractured reservoir partly closed fracture electrical anisotropy fracture roughness

Solid phase based DNA solution of the coloring problem

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Progress in Natural Science:Materials International 2004年第5期 85-88页

作者： PAN Linqiang , LIU Guangwu, XU Jin and LIU Yachun (1. Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 43.074, China 2. Research Group on Mathematical Linguistics, Rovira i Virgili University, Pl. Imperial Tarraco 1, 43.05 Tarragona, Spain 3. Department of Mathematical and Physical Science, Nanhua University, Hengyang 421001, China) Department of Control Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Research Group on Mathematical Linguistics Rovira i Virgili UniversityPl. Imperial Trraco 143005 TarragonaSpain Department of Control Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematical and Physical Science Nanhua UniversityHengyang 421001China

DNA computing has the potential to tackle computationally difficult problems that have real-world implications. The parallel search capabilities of DNA make it a valuable tool for approaching intractable computational problems, for which conventional computers have limited potentials. Up to now, many accomplishments have been achieved to improve its performance and increase its reliability. In this paper, the coloring problem has been solved by means of molecular biology techniques. The coloring problem is a well-known NP-complete problem. This work represents further evidence for the ability of DNA computing to solve NP-complete problems.

关键词： DNA computing NP-complete problem coloring problem.

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KIF4A在结直肠癌中的表达及其临床意义

南京医科大学学报（自然科学版） 2018年第5期38卷 628-632,637页

作者：江涛吴兆映史沛聪杨婷白津徐溢新宋军徐州医科大学研究生学院江苏徐州221004 徐州医科大学肿瘤防治研究所江苏徐州221002 徐州医科大学附属医院胃肠外科江苏徐州221002

目的:探讨人结直肠癌组织中染色体驱动蛋白KIF4A的表达及其临床意义。方法:收集110例手术切除的结直肠癌及相应癌旁5 cm以上结直肠黏膜组织标本,采用免疫组织化学方法检测其中KIF4A的表达情况,并分析KIF4A的表达水平与结直肠癌患者临床... 详细信息

目的:探讨人结直肠癌组织中染色体驱动蛋白KIF4A的表达及其临床意义。方法:收集110例手术切除的结直肠癌及相应癌旁5 cm以上结直肠黏膜组织标本,采用免疫组织化学方法检测其中KIF4A的表达情况,并分析KIF4A的表达水平与结直肠癌患者临床病理特征及其预后之间的关系。结果:结直肠癌组织中KIF4A的表达显著高于癌旁5 cm以上结直肠黏膜组织(P3.、淋巴结转移(P=0.020)、远处转移(P=0.03.)、TNM分期(P0.05)。在随访的110例结直肠癌患者中,Kaplan-Meier生存曲线显示,KIF4A高表达组的5年生存率明显低于KIF4A低表达组(P<0.05)。单因素生存分析显示,KIF4A表达程度、肿瘤分化程度、淋巴结转移、远处转移、TNM分期及血清CEA水平与结直肠癌患者术后生存时间相关。多因素COX比例风险回归模型进一步分析显示,KIF4A表达水平、TNM分期、淋巴结转移和远处转移为结直肠癌患者预后的独立危险因素。结论:KIF4A在结直肠癌组织中高表达,并且其高表达与结直肠的侵袭转移密切相关,KIF4A对于术后结直肠癌患者的预后评估具有参考价值。

关键词：结直肠癌 KIF4A 临床病理预后

基于基础教育课程改革目标的课程实施程度调查

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课程．教材．教法 2016年第5期36卷 14-22页

作者：史丽晶马云鹏东北师范大学吉林长春130024 北京师范大学珠海分校广东珠海519086

调查发现:教师认为课程功能、教学方式、课程评价三类改革目标实施程度良好,而课程结构、课程内容、课程管理三类改革目标实施程度一般;在课程改革目标的实施程度上,小学教师与初中教师、城市教师与农村教师均存在显著差异。我国基础教... 详细信息

调查发现:教师认为课程功能、教学方式、课程评价三类改革目标实施程度良好,而课程结构、课程内容、课程管理三类改革目标实施程度一般;在课程改革目标的实施程度上,小学教师与初中教师、城市教师与农村教师均存在显著差异。我国基础教育课程改革取得了重大成就,但仍然存在诸多问题,我们需要在坚定改革方向的同时,具体问题具体分析,研究促进变革的策略。

关键词：基础教育课程改革课程改革目标课程实施程度

Optimization of Multiplex PCR Systems for Gene-chip Detection of Mutations in Exons in cTnI Gene Associated with FHCM

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稀有金属材料与工程 2006年第S3期 270-273页

作者： Nongyue He~1 Yuanying Zhang~(1,2) Jinan Zhang~3.(1.State Key Laboratory of Bioelectronics,Southeast University,Nanjing 210096,China) (2.Jiangsu Cancer Hospital,Nanjing 210007,China) (3.Research Institute of Cardiovascular Disease,First Affiliated Hospital of Nanjing Medical University,Nanjing 210029,China)

Hypertrophic cardiomyopathy （HCM） is one of the diseases damaging people health most badly and some mutations of exons in cardiac troponin I （cTnI） gene are closely associated with family hypertrophic cardiomyopathy （FHCM）.A microarray was fabricated to screen mutations in exons 3.5,7,and 8 in cTnI *** were designed for the PCR （polymerase chain reaction） to amplify the target DNA fragments from fresh blood *** order to simplify the PCR process,multiplex PCR technology was investigated in *** concentration of Mg2+played an important role in multiplex PCR process,a properly low concentration of Mg2+submitted a better speciality of PCR *** speciality was also favored when the annealing temperature was reasonably enhanced and 64℃is the optimal annealing temperature for the multiplex PCR *** applying the fabricated gene-chip to detect the target fragments from PCR mixture,the signal intensity sequence is in accordance with that from theoretic estimate.

关键词： hypertrophic cardiomyopathy(HCM) gene-chip multiplex PCR mutation hybridization

In-situ Characterization of Non-aqueous Nano-dispersion Systems by Freeze-etching TEM and Comparative Study with Laser Scattering Method

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Journal of Wuhan University of Technology(Materials Science) 2010年第3期25卷 432-436页

作者：欧忠文 Department of Architecture and Civil Engineering Logistics Engineering University

In-situ characterization of non-aqueous nano-dispersion systems（NANDS） by freeze-etching transmission electron microscope（FETEM） was *** improve just-for-once successive rate of specimen preparation and get good characterization results,an improving specimen preparation method of freezing etching was ***,distribution and morphology of NANDS were directly *** information of particle dispersion feature and particle density can also be *** of the FETEM characterization is *** with laser scattering method,which is liable to give positive error especially for small size particle anchoring disperser,FETEM characterization can give more accurate measurement of particle ***,FETEM can give dispersion feature of nanoparticle in non-aqueous medium.

关键词： non-aqueous nano-dispersion system dispersion state in-situ characterization freeze-etching laser scattering method

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动脉化冠状动脉旁路移植术的应用现状

中华外科杂志 2020年第5期58卷 337-340页

作者：赵强杨溢朱云鹏上海交通大学医学院附属瑞金医院心脏外科 200025

旁路血管的选择一直是冠状动脉外科领域的热点。动脉旁路血管具有优良的生物学特性和远期通畅率。近二十年的临床观察和随机临床研究结果显示,胸廓内动脉是"金标准"旁路血管。多支动脉和全动脉冠状动脉旁路移植术可明显改善患者的远期生... 详细信息

旁路血管的选择一直是冠状动脉外科领域的热点。动脉旁路血管具有优良的生物学特性和远期通畅率。近二十年的临床观察和随机临床研究结果显示,胸廓内动脉是"金标准"旁路血管。多支动脉和全动脉冠状动脉旁路移植术可明显改善患者的远期生存,但也存在一定的技术难度和手术风险。国内外学者大力提倡多支动脉或全动脉化冠状动脉旁路移植术,并形成了相应的指南和专家共识。我国的冠状动脉外科进入了质量提升阶段,随着循证医学证据不断积累,动脉化冠状动脉旁路移植术具有良好的应用前景。

关键词：冠状动脉疾病冠状动脉分流术动脉

Randomization of classical inference patterns and its application

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Science in China(Series F) 2007年第6期50卷 867-877页

作者： WANG GuoJun1,2 & HUI XiaoJing1,3. Institute of Mathematics, Shaanxi Normal University, Xi’an 710062, China 2 Research Center for Science, Xi’an Jiaotong University, Xi’an 710049, China 3.College of Mathematics and Computer Science, Yan’an University, 716000, China Institute of Mathematics Shaanxi Normal University Xi’an China Research Center for Science Xi’an Jiaotong University Xi’an China College of Mathematics and Computer Science Yan’an University China

By means of randomization, the concept of D-randomized truth degree of formulas in two-valued propositional logic is introduced, and it is proved that the set of values of D-randomized truth degree of formulas has no isolated point in [0,1]. The concepts of D-logic pseudo-metric and D-logic metric space are also introduced and it is proved that there is no isolated point in the space. The new built D-randomized concepts are extensions of the corresponding concepts in quantified logic. Moreover, it is proved that the basic logic connectives are continuous operators in D-logic metric space. Lastly, three different types of approximate reasoning patterns are proposed.

关键词： D-randomized mapping D-randomized truth degree D-similarity D-logic metric space approximate reasoning