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Codimension 3 nonresonant bifurcations of homoclinic orbits with two inclination flips

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Science china Mathematics 2005年第2期48卷 248-260页

作者： SHUI Shuliang & ZHU Deming college of Mathematics and physics, Zhejiang Normal university, Jinhua 321004. china Department of Mathematics, East china Normal university, Shanghai 200062, china college of Mathematics and physics Zhejiang Normal University Jinhua China Department of Mathematics East China Normal University Shanghai China

Homoclinic bifurcations in four-dimensional vector fields are investigated by setting up a local coordinate near a homoclinic orbit. This homoclinic orbit is principal but its stable and unstable foliations take inclination flip. The existence, nonexistence, and uniqueness of the 1-homoclinic orbit and 1-periodic orbit are studied. The existence of the two-fold 1-periodic orbit and three-fold 1 -periodic orbit are also obtained. It is indicated that the number of periodic orbits bifurcated from this kind of homoclinic orbits depends heavily on the strength of the inclination flip.

关键词： bifurcation, homoclinic orbit, non-resonance, inclination flip, 1-periodic orbit.

β-delayed proton decays near the proton drip line

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2 , CHEN Yongshou 2 , XU Furong 3 , WANG Kun 4., PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 2. Nuclear physics Department, china Institute of Atomic Energy, Beijing 1024.3, china 3. Department of Technical physics, Peking university, Beijing 100871, china 4. Shanghai Institute for Nuclear Research, Shanghai 201800, china Institute of Modern physics Chinese Academy of Sciences Lanzhou China Nuclear physics Department China Institute of Atomic Energy Beijing China Department of Technical physics Peking University Beijing China Shanghai Institute for Nuclear Research Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2004. namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14.nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92Rh as well as the predicted “waiting point” nuclei 89Ru and 93Pd are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2) The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 14.Ho and 128Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3) The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

Effect of Ozone Produced from Antibody-catalyzed Water Oxidation on Pathogenesis of Atherosclerosis

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Acta Biochimica et Biophysica Sinica 2006年第6期38卷 417-422页

作者： Ke-Jun PENG~1,Yu-Shan HUANG~1,Li-Na AN~1,Xiao-Qun HAN~1,Jing-Ge ZHANG~1, Qiu-Lin WANG~2,Jing SUN~1,and Shu-Ren WANG~(1*) ~1 Department of Pathophysiology,West china Preclinical Medical and Forensic Medical college,sichuan university,{4. 61004.,china ~2 The First Department of Internal Medicine,The First Hospital Affiliated to {4. Medical college,{4. 610500,china Department of Pathophysiology West China Preclinical Medical and Forensic Medical College Sichuan UniversityChengdu 610041 China The First Department of Internal Medicine The First Hospital Affiliated to Chengdu Medical CollegeChengdu 610500 China

Recent studies have suggested that antibodies can catalyze the generation of unknown oxidantsincluding hydrogen peroxide （H2O2） and ozone （O3） from singlet oxygen （1O2） and *** study is aimedto detect the effect of antibody-catalyzed water oxidation on *** results showed that bothH2O2and O_ were produced in human leukemia THP-1 monocytes incubated with human immunoglobulin Gand phorbol myristate *** the THP-1 monocytes incubated with human immunoglobulin G,phorbolmyristate acetate and low density lipoprotein the intracellular total cholesterol,free cholesterol,cholesterylester and lipid peroxides clearly increased,and a larger number of foam cells were observed by oil red *** accumulation of all intracellular lipids was significantly inhibited by vinylbenzoic acid,and onlyslightly affected by *** findings suggested that the production of O3,rather than H2O2,might beinvolved in the pathogenesis of atherosclerosis through the antibody-catalyzed water oxidation pathway.

关键词： antibody ozone THP-1 monocyte foam cell atherosclerosis

Theoretical study of ZnO adsorption and bonding on Al_2O_3(0001) surface

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2,XUE Weidong1,LI Jinshan3 & LIU Yonghua3 1.Institute of Microelectronics and Solid State Electronics,university of Electronic Science and Technol- ogy of china,chengdu 610054.china 2.Institute of Mathematics and Software Science,{4. Normal university,chengdu 610068,china 3.Institute of Chemical Materials,china Academy of Engineering physics,Mianyang 621000,china Institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China Institute of Chemical Materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 4.4.3(±38.6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 30° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 30°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2 of the ZnO ? and the surface Al3+ has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2+ and the surface O2 has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4. and the O 2p and partially from that of the Zn 3d and the O 2p.

关键词： α-Al2O3 (0001) ZnO ab initio molecular dynamics chemical adsorption density of states

Further research on high-spin structure in ^(161)Lu

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Science china(physics,Mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1,2,YU ShaoYing1,2,4.SHEN CaiWan1,5,LI XiaoWei6 & CHEN YongShou3,4.1 School of Science,Huzhou Teachers college,Huzhou 313000,china 2 college of Mathematics,physics and Information Engineering,Zhejiang Normal {4.,Jinhua 321000,china 3 china Institute of Atomic Energy,Beijing 1024.3,china 4.Institute of Theoretical physics,Chinese Academy of Sciences,Beijing 100080,china 5 Center of Theoretical Nuclear physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china 6 Department of physics,Chifeng {4.,Chifeng 024.01,china School of Science Huzhou Teachers College Huzhou China college of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua China Institute of Theoretical physics Chinese Academy of Sciences Beijing China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China Department of physics Chifeng University Chifeng China china Institute of Atomic Energy Beijing China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2 in 161Lu. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i13/2 also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4. BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 3. college of Resources and Environment, Southwest Agricultural university, Chongqing 4.0716, china 4. The Ministry of Science and Technology, P. C. china, Beijing 100862, china 5. chengdu Institute of Biology, Chinese Academy of Sciences, chengdu 61004., china Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of the Chinese Academy of Sciences Beijing China college of Resources and Environment Southwest Agricultural University Chongqing China The Ministry of Science and Technology P. C. China Beijing China chengdu Institute of Biology Chinese Academy of Sciences Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2000 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2000, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.4.%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2000, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Ligands of Peroxisome Proliferator-activated Receptor Inhibit Homocysteineinduced DNA Methylation of Inducible Nitric Oxide Synthase Gene

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Acta Biochimica et Biophysica Sinica 2007年第5期39卷 366-376页

作者： Yideng JIANG~(1*), Jianzhong ZHANG~1, Jiantuan XIONG~1, Jun CAO~1, Guizhong LI~1, and Shuren WANG~2 1 Department of Pathology, Ningxia Medical college, Yinchuan 750004. china 2 Department of Pathophysiology, West china college of Preclinical and Forensic Medical Sciences,{4., chengdu 61004., china Department of Pathology Ningxia Medical CollegeYinchuan 750004 China Department of Pathophysiology West China College of Preclinical and Forensic Medical Sciences Sichuan UniversityChengdu 610041 China

Homocysteine (Hcy) is a risk factor for atherosclerosis. It is generally accepted that inducible nitric oxide synthase (iNOS) is a key enzyme in the regulation of vascular disease. The aim of the present study is to investigate the effects of peroxisome proliferator-activated receptor ligands on iNOS in the presence of Hcy in human monocytes. Foam cells, induced by oxidize low density lipoprotein (ox-LDL) and phorbol myristate acetate (PMA) in the presence of different concentrations of Hcy, clofibrate and pioglitazone in human monocytes for 4.d, were examined by oil red O staining. The activity of iNOS was detected by real-time quantitative reverse transcription-polymerase chain reaction and Western blot analysis. The capability of DNA methylation was measured by assaying endogenous C5 DNA methyltransferase (C5MTase) activity, and the iNOS promoter methylation level was determined by quantitative MethyLight assays. The results indicated that Hcy increased the activity of C5MTase and the level of iNOS gene DNA methylation, resulting in a decrease of iNOS expression. Clofibrate and pioglitazone could antagonize the Hcy effect on iNOS expression through DNA methylation, resulting in attenuation of iNOS transcription. These findings suggested that Hcy decreased the expression of iNOS by elevating iNOS DNA methylation levels, which can repress the transcription of some genes. Peroxisome proliferator-activated receptor α/γ ligands can down- regulate iNOS DNA methylation, and could be useful for preventing Hcy-induced atherosclerosis by repressing iNOS expression.

关键词： homocysteine DNA methyltransferase PPARα/γ ligand iNOS DNA methylation

Noether-Form Invariance of Nonholonomic Controllable Mechanical Systems in Phase Space

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Communications in Theoretical physics 2007年第7期48卷 23-26页

作者： XIA Li-Li LI Yuan-Cheng college of physics Science and Technology,china university of Petroleum,Dongying 257061,china college of physics Science and Technology China University of Petroleum Dongying 257061 China

In this paper,we study the Noether-form invariance of nonholonomic mechanical controllable systems inphase *** of motion of the controllable mechanical systems in phase space are *** definitionand the criterion for this system are presented.A new conserved quantity and the Noether conserved quantity deducedfrom the Noether-form invariance are *** example is given to illustrate the application of the results.

关键词： nonholonomic controllable mechanical system phase space Noether-form invariance conserved quantity

Tanshinone prevents cancellous bone loss induced by ovariectomy in rats

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Acta Pharmacologica Sinica 2004年第5期25卷 136-142页

作者： Liao CUI2,3, Tie WU3, Yu-yu LIU3, Yi-feng DENG4. Chun-mei AI4. Huai-qing CHEN22Institue of Biomedical Engineering, West china Medical Center, sichuan university, chengdu 61004., china 3Department of Pharmacology, 4.uangdong Key Laboratory for Research and Development of Natural Drugs,Guangdong Medical {4., Zhanjiang 524.23 china 四川大学 Chengdu 610041 Department of Pharmacology Guangdong Medical College Zhanjiang 524023 Department of Pharmacology Guangdong Medical College Zhanjing 524023 Guangdong Medical college Guangdong Key Laboratory for Research and Development of Natural Drugs Zhanjiang 524023

AIM: To investigate the skeletal effects of total tanshinone in ovariectomized rats by analyzing cancellous bonehistomorphometry of fourth lumbar vertebrae (LV4. and proximal tibial metaphyses (PTM). METHODS: Four-month-old Sprague-Dawley female rats were sham-operated and treated with vehicle or ovariectomized and treatedwith either vehicle, total tanshinone (200 mgkg-1d-1, equivalent to 35 gkg-1d-1 of tanshinone II A and 16 mgkg -1d-1 ofcryptotanshinone), or 17a-ethynylestradiol (30 gkg-1d-1 as positive treatment group) starting one day post-sur-gery for 10 weeks. Double in vivo fluorochrome labeling was administered to all rats. The undecalcified longitu-dinal LV4.and PTM sections were cut and stained with Goldners Trichrome (4.m thickness) or unstained (8-mthickness) for the bone histomorphometric analysis. RESULTS: A significant decrease in trabecular bone volume(BV/TV) and trabecular number (Tb.N) and a significant increase in osteoclast surface (OCS/BS) and mineralizingsurface (MS/BS) were found in both LV and PTM of vehicle-treated OVX rats compared with sham *** completely prevented the decreases in BV/TV and Tb.N and the increase in OCS/BS in the LV4. andpartially prevented the decreases in BV/TV and Tb.N in the PTM of OVX rats. In addition, tanshinone increasedtrabecular thickness (***) whereas it did not alter MS/BS. Moreover, tanshinone had no effect on uterine weightand body weight of OVX rats. Estrogen treatment increased BV/TV and Tb.N and decreased OCS/BS, but, alsomarkedly decreased MS/BS and increased uterine weight in OVX rats. CONCLUSION: The current study demon-strated that the adequate supply of tanshinone prevented OVX-induced cancellous bone loss in rats through inhibi-tion of elevated bone resorption.

关键词： tanshinone cryptotanshinone 2-fluoro-17alpha-ethynylestradiol ovariectomy bone and bones osteoclasts osteoporosis histocytochemistry morphology