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Acta Mathematica Sinica,English Series 2007年第8期23卷 1495-1504页

作者： de ming zhu Ying SUN department of Mathematics East China Normal University Shanghai 200062 P. R. China School of Science University of Ji'nan Ji'nan 250022 P. R. China

In this paper, we study the dynamical behavior for a 4-dimensional reversible system near its heteroclinic loop connecting a saddle-focus and a saddle. The existence of infinitely many reversible 1-homoclinic orbits to the saddle and 2-homoclinic orbits to the saddle-focus is shown. And it is also proved that, corresponding to each 1-homoclinic （resp. 2-homoclinic） orbit F, there is a spiral segment such that the associated orbits starting from the segment are all reversible 1-periodic （resp. 2-periodic） and accumulate onto F. Moreover, each 2-homoclinic orbit may be also accumulated by a sequence of reversible 4-homoclinic orbits.

关键词： reversible condition homoclinic orbit Poincare map periodic orbit saddle-focus

Homoclinic Bifurcation of Orbit Flip with Resonant Principal Eigenvalues

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Acta Mathematica Sinica,English Series 2006年第3期22卷 855-864页

作者： Tian Si ZHANG de ming zhu department of Mathematics East China Normal University

Codimension-3 bifurcations of an orbit-flip homoclinic orbit with resonant principal eigenvalues are studied for a four-dimensional system. The existence, number, co-existence and noncoexistence of 1-homoclinic orbit, 1-periodic orbit, 2n-homoclinic orbit and 2n-periodic orbit are obtained. The bifurcation surfaces and existence regions are also given.

关键词： Orbit flip Homoclinic orbit Periodic orbit Resonance Principal eigenvalues

Codimension-4 Resonant Homoclinic Bifurcations with Orbit Flips and Inclination Flips

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Acta Mathematica Sinica,English Series 2015年第8期31卷 1359-1366页

作者： Tian Si ZHANG de ming zhu College of Science University of Shanghai for Science and Technology department of Mathematics East China Normal University

The paper studies a codimension-4 resonant homoclinic bifurcation with one orbit flip and two inclination flips, where the resonance takes place in the tangent direction of homoclinic *** active coordinate system is introduced to construct the Poincar′e returning map, and also the associated successor functions. We prove the existence of the saddle-node bifurcation, the perioddoubling bifurcation and the homoclinic-doubling bifurcation, and also locate the corresponding 1-periodic orbit, 1-homoclinic orbit, double periodic orbits and some 2n-homoclinic orbits.

关键词： Orbit flip inclination flip resonant homoclinic-doubling bifurcations

New Oscillation Criteria for Second Order Linear Matrix Differential Equations with Damping

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Acta Mathematica Sinica,English Series 2008年第6期24卷 925-936页

作者： Yan Cong XU de ming zhu department of Mathematics East China Normal University Shanghai 200062 P. R. China

By using the positive linear functional and the monotone subhomogeneous functional, including the general means and Riccati technique, some new oscillation criteria are established for the second order linear matrix differential system （P（t）X＇（t））＇＋ R（t）X＇（t）＋ Q（t）X（t） =0, t ≥ to 〉 0 where P（t）, R（t）, Q（t） are n × n real continuous matrix functions, P（t） and R（t） are commutative. Theresults improve and generalize those given in some previous papers, which can be seen by the examples given at the end of this paper.

关键词： matrix differential equation oscillation damping

Improvement on electrochemical performances of nanoporous titania as anode of lithium-ion batteries through annealing of pure titanium foils

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Journal of Energy Chemistry 2018年第1期27卷 250-263页

作者： Md.Arafat Rahman Yat Choy Wong Guangsheng Song de ming zhu Cuie Wen Faculty of Science Engineering and TechnologySwinburne University of Technology department of Mechanical Engineering Chittagong University of Engineering and Technology School of Material Science&Engineering Anhui University of Technology School of Engineering RMIT University

The effect of annealing of Ti foils before anodization on the morphology and electrochemical performance of resultant nanoporous anatase TiO2 （np-TiO2） as anode in rechargeable lithium-ion batteries （LIBs） was investigated. The np-TiO2 anode fabricated from annealed Ti foils exhibited higher specific surface area and reduced pore diameter compared to np-TiO2 electrode fabricated from as-received Ti foils. The highly porous np-TiO2 anode fabricated from annealed Ti foils exhibited 1st discharge capacity of 453.25 mAh/g and reduced to 172.70 mAh/g at 1 C current rate after 300 cycles; whilst the np-TiO2 electrode fabricated from the as-received Ti foils exhibited 1st discharge capacity of 213.30 mAh/g and reduced to 160.0 mAh/g at 1 C current rate after 300cycles. Even after 400cycles, such np-TiO2 electrode exhibited a reversible capacity of 125.0 mAh/g at 2.5 C current rate. Compared to the untreated Ti foils, the enhanced electro- chemical performance of np-TiO2 anode fabricated from annealed Ti foils was ascribed to the annealing- induced removal of residual stress among the Ti atoms. The benefit of annealing process can reduce pore size of as-fabricated np-TiO2.

关键词： Annealing Nanoporous Anatase Titanium oxide Anode Lithium-ion battery

Hepatitis B virus X protein promotes proliferation and upregulates TGF-β1 and CTGF in human hepatic stellate cell line,LX-2

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Hepatobiliary & Pancreatic Diseases International 2009年第1期8卷 59-64页

作者： Guang-Hui Guo,de-ming Tan,Ping-An zhu and Fei Liu department of Infectious Diseases,Xiangya Hospital,Central South University,Changsha 410008,China department of Infectious Diseases Xiangya Hospital Central South University Changsha 410008 China. guanghuiguo2008@***

BACKGROUND:Chronic hepatitis B virus(HBV)infection is a major cause of liver fibrosis,but the mechanisms underlying HBV-related fibrogenesis are still unknown. Although the roles of HBV X protein(HBx)remain poorly understood,it is thought to play an important role in the regulation of cellular growth and hepatocarcinogenesis. The aim of this study was to determine the role of HBx in liver fibrogenesis by studying the effect of HBx on the proliferation and expression of fibrosis-related molecules in the human hepatic stellate cell line,LX-2. METHODS:We established an in vitro co-culture system with LX-2 cells and a stable QSG7701-HBx cell line which had been transfected with the HBx gene. 3 H-TdR incorporation and flow cytometry were used to determine the effects of HBx on the proliferation of LX-2 cells. α-smooth muscle actin(α-SMA),transforming growth factor-β1(TGF-β1),transforming growth factor-βreceptor Ⅱ(TGF-βRⅡ),and connective tissue growth factor (CTGF)in LX-2 cells were analyzed by Western *** addition,the expression levels of collagen typeⅠ(ColⅠ) from the co-cultured media were measured by ELISA. RESULTS: 3 H-TdR incorporation increased significantly in LX-2 cells co-cultured with QSG7701-HBx cells compared to those cultured with QSG7701-pcDNA3 and QSG7701 (non-tumorigenic human liver cell line).Cell cycle results revealed that HBx accelerated the progression of G1 to S in LX-2 *** expressions ofα-SMA,TGF-β1,TGF-βR Ⅱ,CTGF and ColⅠwere significantly increased in the co- cultures of LX-2 cells with stable QSG7701-HBx cells. CONCLUSION:These results suggest that HBx may facilitate liver fibrosis by promoting hepatic stellate cell proliferation and upregulating the expression of fibrosis- related molecules.

关键词： hepatitis B virus HBx liver cirrhosis hepatic stellate cell proliferation

Application and Effects of Ultrasound in Hevea brasiliensis

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Application and Effects of Ultrasound in Hevea brasiliensis

2014年中国作物学会学术年会

作者： Cuifang DUAN Zhiyi NIE Rizhong Zeng Wei-fu LIN Ling-xue KONG de-ming zhu Institute of Rubber Research Chinese Academy of Tropical Agricultural Sciences/Ministry of Agriculture Key Laboratory for Rubber Tree Biology/State Key Laboratory Incubation Base

Ultrasound is a form of mechanical *** can vibrate and move particles within a specific medium,therefore has been extensively used as an effective method for faster mixing,energy and mass transfer,selective extraction,faster response to process *** instance,more recently,ultrasound assisted technology has been applied to modern waste water treatment,and food processing etc as ultrasound irradiation will result in cavitations phenomena and enhancement in mass *** has strong biological effects when it was applied in different *** can influence plant physiologies,such as respiration intensity,germination rate,rooting,and some metabolic *** can play an important role in the cell growth and secondary metabolite biosynthesis since ultrasound stimulation is beneficial not only to inducing the defense responses,but also to the secondary metabolites *** study aims to investigate the potential of using ultrasound-assisted technology to increase rubber yield from the Para rubber tree Hevea *** influence of ultrasound treatment on latex yield,dry rubber content has been observed and further evaluated by analyzing the physiological mechanism of ultrasound acting on the ***,the molecular mechanism of ultrasound on the latex was also *** study on ultrasound application in Hevea brasiliensis will help not only to understand how the ultrasound improves the latex yield,but also be useful on the future application of ultrasound on the other latex producing plants.

关键词： ultrasonic wave Hevea brasiliensis ultrasound latex rubber tree

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具有双轨道翻转性质的同宿分支

数学学报（中文版） 2009年第1期52卷 33-46页

作者：邓桂丰朱德明徐衍聪上海立信会计学院数学与统计学系上海201620 华东师范大学数学系上海200062 杭州师范大学数学系杭州310036

研究了4维系统中连接强稳定与强不稳定方向的同宿轨线分支问题．不仅得到了1-同宿轨线，2^n-同宿轨线，1-周期轨线和2^n-周期轨线的存在性、数目、共存性和非共存性等结论，而且给出了系统的分支图．

关键词：同宿轨线非主特征方向周期轨线

重症胰腺炎肾脏损伤中细胞凋亡相关基因的作用

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世界华人消化杂志 2005年第17期13卷 2103-2107页

作者：朱明德方驰华史学深南方医科大学珠江医院肝胆外科广东省广州市510282

目的:探讨细胞凋亡及bax,bcl-2基因表达在重症胰腺炎(SAP)肾脏损伤中的作用.方法:大鼠30只随机分为假手术组(SO组,n=15)和SAP组(n=15),采用50g/L牛磺胆酸钠逆行胆胰管注射法建立SAP模型,建模后6,12,18h测定血Cr,BUN,光镜、电镜观察肾组... 详细信息

目的:探讨细胞凋亡及bax,bcl-2基因表达在重症胰腺炎(SAP)肾脏损伤中的作用.方法:大鼠30只随机分为假手术组(SO组,n=15)和SAP组(n=15),采用50g/L牛磺胆酸钠逆行胆胰管注射法建立SAP模型,建模后6,12,18h测定血Cr,BUN,光镜、电镜观察肾组织病理变化,TUNEL法测定肾脏细胞凋亡,SABC免疫组化染色法测定bax,bcl-2基因表达.结果:SAP组血Cr,BUN较假手术组升高,光电镜下见肾组织损害明显.肾小球细胞凋亡数明显高于对照组(6,12,18h分别为3.2±1.1vs0.8±0.1,P<0.05;3.9±1.8vs0.9±0.1,P<0.05;4.8±1.7vs0.8±0.2,P<0.01),肾小管细胞凋亡数明显高于对照组(6,12,18h分别为9.8±1.1vs1.3±0.5,P<0.01;12.6±2.3vs1.2±0.3,P<0.01;15.7±2.6vs1.3±0.3,P<0.01),肾小球bax表达水平明显高于对照组(6,12,18h分别为3.05±0.86vs1.01±0.04,P<0.05;3.37±1.13vs1.06±0.05,P<0.05;4.11±1.24vs1.09±0.03,P<0.05),肾小管bax表达水平也明显高于对照组(6,12,18h分别为8.17±2.16vs1.53±0.07,P<0.01;12.92±1.81vs1.61±0.05,P<0.01;13.08±2.53vs1.59±0.05,P<0.01),并且随病程延长而逐渐增高.bcl-2表达主要在肾小管区,其表达水平也高于对照组(6,12,18h分别为3.38±1.07vs1.58±0.02,P<0.05;4.26±1.13vs1.59±0.06,P<0.05;7.21±1.04vs1.61±0.02,P<0.01),肾小球区的bcl-2表达水平也高于对照组(6,12,18h分别为2.18±0.65vs1.04±0.02;2.42±0.63vs1.03±0.05,P<0.05;2.69±0.47vs1.08±0.04,P<0.05),但随病程延长而逐渐下降.结论:SAP肾脏损伤的发病与肾脏细胞凋亡有关,可能是通过上调bax表达并下调bcl-2表达而引起细胞凋亡.

关键词：重症胰腺炎 bax bel-2 肾细胞凋亡

连接两个具有一维不稳定流形的双曲鞍点异宿环的稳定性

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数学学报（中文版） 2018年第5期61卷 761-770页

作者：路秋英邓桂丰刘潇朱德明上海立信会计金融学院统计与数学学院上海201209 华东师范大学数学系上海200241

本文研究任意有限维空间中连接两个具有一维不稳定流形的双曲鞍点异宿环的稳定性.借助适当的线性变换和坐标变换,将局部稳定流形和不稳定流形拉直,利用奇异流映射和正则流映射构造了Poincaré映射.通过技巧性地估计向量的模,给出了在横... 详细信息

本文研究任意有限维空间中连接两个具有一维不稳定流形的双曲鞍点异宿环的稳定性.借助适当的线性变换和坐标变换,将局部稳定流形和不稳定流形拉直,利用奇异流映射和正则流映射构造了Poincaré映射.通过技巧性地估计向量的模,给出了在横截面上Poincaré映射的初始点与首次回归点离异宿轨道与横截面交点的距离之比,得到了高维空间中连接两个带有一维不稳定流形的异宿环的非常简洁的稳定性判据.

关键词：高维系统异宿环稳定性 Poincaré映射