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World Journal of Gastroenterology 2009年第20期15卷 2500-2505页

作者： ye zong Shu-Tian Zhang Sheng-Tao Zhu Department of Gastroenterology Beijing Friendship Hospital Affiliated to the Capital Medical University Beijing Digestive Disease Center Beijing 100050 China

AIM： To study the effect of nicotine on the migration and invasion of human esophageal squamous carcinoma cells and to investigate whether nimesulide can inhibit the effect of ***： The esophageal squamous carcinoma cell line （TE-13） was treated with different concentrations of nicotine （100 μg/mL and 200 μg/mL） or 200 μg/mL nicotine plus 100 μmol/L nimesulide. Cell migration and invasion were measured using migration and invasion chamber systems. COX-2 expression was determined by Western blotting. Matrix metalloproteinase-2 （MMP-2） was analyzed by zymography and ***： Nicotine （100 μg/mL, 200 μg/mL） enhanced TE-13 cells migration and invasion, and increased the protein expression of COX-2 and the activity of MMP-2. Nicotine （200 μ/mL） stimulated TE-13 cells migration and invasion which were partly blocked by nimesulide. This was associated with decreased protein expression of COX-2 and decreased activity and protein expression of MMP-2. CONCLUSION： Nicotine enhances the migration and invasion of the esophageal squamous carcinoma cell line, and nimesulide partly blocks the effect ofnicotine-enhanced esophageal squamous carcinoma cell migration and invasion.

关键词： Carcinoma Cyclooxygenase 2 inhibitors Esophagus Nicotine Squamous cell

Nuclear Matter in a Chiral SU(3) Quark Mean-Field Model

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Communications in Theoretical Physics 2001年第7期36卷 71-78页

作者： WANG Ping ZHANG zong-ye YU You-Wen Institute of High Energy Physics Academia Sinica P.O. Box 918(4) Beijing 100039 China Institute of High Energy Physics Academia Sinica P.O. Box 918(4) Beijing 100039 China Institute of High Energy Physics Academia Sinica P.O. Box 918(4) Beijing 100039 China

A quark meson coupling model based on SU(3)L × SU(3)R symmetry and scale invariance is *** quarks and mesons get masses through symmetry broken. We apply this SU(3) chiral constituent quark model to investigating the nuclear matter at finite temperature and density. The effective baryon masses, compression modulus and hyperon potentials are all reasonable. The critical temperature ofliquid-gas phase transition is also calculated in this model.

关键词： chiral symmetry, constituent quark, nuclear matter, hyperon potentials

QQqq Four-Quark Bound States in Chiral SU(3) Quark Model

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Communications in Theoretical Physics 2008年第8期50卷 437-440页

作者： ZHANG Ming ZHANG Hai-Xia ZHANG zong-ye Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100049 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China School of Biomedical Engineering Capital Medical University Beijing 100069 China

Abstract The possibility of QQqq heavy-light four-quark bound states has been analyzed by means of the chiral SU（3） quark model, where Q is the heavy quark （c or b） and q is the light quark （u, d, or s）. We obtain a bound state for the bbnn configuration with quantum number JR=1^＋, I = 0 and for the ccnn （JR=1^＋, I=O） configuration, which is not bound but slightly above the D^＊ D^＊ threshold （n is u or d quark）. Meanwhile, we also conclude that a weakly bound state in bbnn system can also be found without considering the ehiral quark interactions between the two light quarks, yet its binding energy is weaker than that with the chiral quark interactions.

关键词： four-quark states quark model chiral symmetry

Contribution of myeloid-derived suppressor cells to tumor-induced immune suppression,angiogenesis,invasion and metastasis

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Journal of Genetics and Genomics 2010年第7期37卷 423-430页

作者： Xian-zong ye Shi-Cang Yu Xiu-Wu Bian Institute of Pathology and Southwest Cancer Center Southwest Hospital Third Military Medical University Chongqing 400038 China

Growing evidence suggests that myeloid-derived suppressor cells （MDSCs）,which have been named ＂immature myeloid cells＂ or ＂myeloid suppressor cells＂（MSCs）,play a critical role during the progression of cancer in tumor-bearing mice and cancer *** their name implies,these cells are derived from bone marrow and have a tremendous potential to suppress immune *** studies indicated that these cells also have a crucial role in tumor *** can directly incorporate into tumor *** secret many pro-angiogenic factors as *** addition,they play an essential role in cancer invasion and metastasis through inducing the production of matrix metalloproteinases （MMPs）,chemoattractants and creating a pre-metastatic *** evidence supports the idea that cancer stem cells （CSCs） are responsible for tumorigenesis,resistance to therapies,invasion and ***,we hypothesize that CSCs may ＂hijack＂ MDSCs for use as alternative niche cells,leading to the maintenance of stemness and enhanced chemo-and radio-therapy *** countermeasure that directly targets to MDSCs may be useful for against angiogenesis and preventing cancer from invasion and ***,the study of MDSCs is important to understand tumor progression and to enhance the therapeutic efficacy against cancer.

关键词： myeloid-derived suppressor cells immune suppression angiogenesis invasion metastasis

Low-Energy Kπ Phase Shifts in Chiral SU（3） Quark Model

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Communications in Theoretical Physics 2005年第4X期44卷 665-669页

作者： HUANG Fei ZHANG zong-ye YU You-Wen Institute of High Energy Physics P.O. Box 918-4 Beijing 100049 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

The low-energy region kaon-pion S- and P-wave phase shifts with isospin I = 1/2 and I = 3/2 are dynamically studied in the chiral SU(3) quark model by solving a resonating group method equation. The model parameters are taken to be the values fitted by the energies of the baryon ground states and the kaon-nucleon elastic scattering phase shifts of different partial waves. As a preliminary study the s-channel q(-q) annihilation interactions are not included since they only act in the very short range and are subsequently assumed to be unimportant in the low-energy domain. The numerical results are in qualitative agreement with the experimental data.

关键词： Kπ phase shifts quark model chiral symmetry

Hot deformation characteristics of as-cast high-Cr ultra-super-critical rotor steel with columnar grains

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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1275-1285页

作者： zong-ye Ding Qiao-dan Hu Long Zeng Jian-guo Li School of Materials Science and Engineering Shanghai Jiao Tong University Laboratory of Advanced Materials and Solidification Shanghai Jiao Tong University

Isothermal hot compression tests of as-cast high-Cr ultra-super-critical（USC） rotor steel with columnar grains perpendicular to the compression direction were carried out in the temperature range from 950 to 1250°C at strain rates ranging from 0.001 to 1 s^（-1）. The softening mechanism was dynamic recovery（DRV） at 950°C and the strain rate of 1 s^（-1）, whereas it was dynamic recrystallization（DRX） under the other conditions. A modified constitutive equation based on the Arrhenius model with strain compensation reasonably predicted the flow stress under various deformation conditions, and the activation energy was calculated to be 643.92 kJ ×mol^（-1）. The critical stresses of dynamic recrystallization under different conditions were determined from the work-hardening rate（θ）–flow stress（σ） and-θ/σ–σ curves. The optimum processing parameters via analysis of the processing map and the softening mechanism were determined to be a deformation temperature range from 1100 to 1200°C and a strain-rate range from 0.001 to 0.08 s^（-1）, with a power dissipation efficiency η greater than 31%.

关键词： rotor steel columnar grains dynamic recrystallization constitutive models critical conditions processing maps

Understanding the structure of d~*(2380) in chiral quark model

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Science China(Physics,Mechanics & Astronomy) 2016年第2期59卷 40-48页

作者： Fei Huang Peng Nian Shen Yu Bing Dong zong ye Zhang School of Physical Sciences University of Chinese Academy of Sciences Institute of High Energy Physics Chinese Academy of Sciences Theoretical Physics Center for Science Facilities Chinese Academy of Sciences College of Physics and Technology Guangxi Normal University

The structure and decay properties of d＊ have been detailedly investigated in both the chiral SU（3） quark model and the extended chiral SU（3） quark model that describe the energies of baryon ground states and the nucleon-nucleon （NN） scattering data satisfactorily. By performing a dynamical coupled-channels study of the system of △△ and hidden-color channel （CC） with quantum numbers l（JP） = 0（3^＋） in the framework of the resonating group method （RGM）, we find that the d＊ has a mass of about 2.38-2.42 GeV and a root-mean-square radius （RMS） of about 0.76-0.88 fm. The channel wave function is extracted by a projection of the RGM wave function onto the physical basis, and the fraction of CC component in the d＊ is found to be about 66%-68%, which indicates that the d＊ is a hexaquark-dominated exotic state. Based on this scenario the partial decay widths of d＊ → dπ^0π^0 and d＊ → dn^＋n^- are further explicitly evaluated and the total width is then obtained by use of the branching ratios extracted from the measured cross sections of other possible decay channels. Both the mass and the decay width of d＊ calculated in this work are compatible with the data （M ≈ 2380 MeV, F ≈ 70 MeV） reported by WASA-at-COSY Collaboration.

关键词： hexaquark state d*(2380) quark model hidden-color channel

An atomic insight into effect of grain boundary on diffusion behavior of Cu/Al dissimilar materials undergoing ultrasonic welding

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Journal of Iron and Steel Research International 2024年第10期31卷 2555-2567页

作者： Jing-wei Yang Chu-hao Xie Jie Zhang zong-ye Ding Jian Qiao School of Mechatronic Engineering and Automation Foshan UniversityFoshan528225GuangdongChina School of Mechanical Engineering University of Science and Technology BeijingBeijing100083China Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of Advanced Brazing Filler Metals&Technology Zhengzhou Research Institute of Mechanical Engineering Co.Ltd.Zhengzhou450001HenanChina

The diffusion processes in bicrystalline Cu/Al joints,characterized by typical high-angle grain boundaries(GBs),were investigated using molecular dynamics *** was found that GBs facilitated the diffusion of both Cu and Al atoms,predominantly enhancing the migration of Cu atoms into Al *** to mean squared displacement results,the movement of Al atoms within Al matrix was more vigorous than that of Cu *** mechanisms of atomic rearrangement,dislocation movement,stacking fault formation,and dynamic recrystallization were *** the compression and initial welding stages,the mismatch in lattice constants and the twisting of grains initiated a squeeze-induced rearrangement of Al atoms at the interface,leading to the formation of dislocations and *** the advanced stages of welding,the plastic deformation primarily occurred within Al matrix,marked by the emergence of dislocations,stacking faults,and GB ***,the shearing effect during the ultrasonic welding process,combined with GB sliding,collectively induced grain recrystallization at the ***,the diffusion between Cu/Al joints could be enhanced by increasing the vibration frequency,due to a significant rise in the number of amorphous regions.

关键词： Grain boundary Molecular dynamics Diffusion behavior Ultrasonic welding Dissimilar material

Constitutive analysis and optimization on hot working parameters of as-cast high Cr ultra-super-critical rotor steel with columnar grains

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Journal of Iron and Steel Research International 2017年第9期24卷 916-924页

作者： zong-ye Ding Di Zhang Qiao-dan Hu Long Zeng Jian-guo Li School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory of Materials Laser Processing and Modification Shanghai Jiao Tong UniversityShanghai 200240China

Isothermal hot compression tests on the as-cast high-Cr ultra-super-critical rotor steel with columnar grains were carried out in the temperature range from 1223 to 1523Kand at strain rates from 0.001 to 1s^（-1）.The compression direction was parallel to the longitudinal direction of columnar *** constitutive equation based on Arrhenius model was presented,and the processing maps based on the dynamic material model were developed,correlating with microstructure *** main softening mechanism was dynamic recovery at 1223 Kunder strain rates from 0.1to 1s^（-1）,whereas it was dynamic recrystallization under other deformation *** constitutive equation modified by strain compensation reasonably predicted the flow *** processing maps and microstructure evolution mechanism schematic indicated that the optimum hot working parameters lay in the zone defined by the temperature range from 1423 to 1473Kand the strain rate range from 0.001 to 1s^（-1）.

关键词： As-cast ultra-super-critical rotor steel Columnar grain Dynamic recrystallization Modified constitutive equation Processing map

Chiral SU(3) Quark Model Study of Tetraquark States: cn■/cs

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Communications in Theoretical Physics 2008年第2期49卷 414-420页

作者： ZHANG Hai-Xia WANG Wen-Ling DAI Yuan-Ben ZHANG zong-ye Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100049 China Institute of Particle Physics Central China Normal University Wuhan 430079 China Institute of Theoretical Physics the Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China

The new members of the charm-strange family Dsj^＊（2317）, Dsj（2460）, and Ds（2632）, which have the surprising properties, are challenging the present models. Many theoretical interpretations have been devoted to this issue. Most authors suggest that they are not the conventional cs^- quark model states, but possibly are four-quark states, molecule states, or mixtures of a P-wave cs^- and a four-quark state. In this work, we follow the four-quark-state picture, and study the masses of cnn^-s^-/css^-s^- states （n is u or d quark） in the chiral SU（3） quark model. The numerical results show that the mass of the mixed four-quark state （cnn^-s^-/css^-s^-） with spin parity j^P ： 0^＋ might not be Ds （2632）. At the same time, we also conclude that Dsj^＊（2317） and Dsj（2460） cannot be explained as the pure four-quark state.

关键词： four-quark states quark model chiral symmetry