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Point Groups and Single Forms of Quasicrystals with Eightfold and Twelvefold Symmetry

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 39-43页

作者： Shi Nicheng and Liao Libing beijing graduate School, china university of Geosiences, beijing beijing graduate School China University of Geosiences Beijing

This paper mainly deals with the point groups and single forms of octagonal quasicrystals and the description of one-dimensional quasilattice. The authors present a new sequence for describing the arrangement of quasiperiods in one-dimensional quasilattice. The first ten numbers of quasiperiods of this sequence are 1, 1, 2, 5, 12, 29, 70, 169, 4.8 and 985. The arrangement of quasiperiods in the first five steps are a, b, ab. babab and babababbabab. Seven p(?)nt groups and nine single forms for the octagonal system have been deduced, They are as follows: Point groups: 8.8m, 82, 8/m, 8/mmm, 8 and 82m; single forms: octagonal prism, dioctagonal prism. octagonal pyramid. dioctagonal pyramid. octagonal dipyramid, dioctagonal dipyramid, octagonal scalenohedron, dioctagonal scalenohedron and octagonal trapezohedron. Besides seven point groups and nine single forms for the dodecahegonal system have also been deduced.

关键词： Point Groups and Single Forms of Quasicrystals with Eightfold and Twelvefold Symmetry

Spatial heterogeneity of the driving forces of cropland change in china

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Science china Earth Sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2, WANG Jinfeng1, LIU Mingliang4.1 & MENG Bin1,2,3 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 Arts and Sciences of beijing Union university, beijing 100083, china 4. School of Forestry and Wildlife Sciences, Auburn university, Auburn, Alabama, AL3684., USA Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate School of the Chinese Academy of Sciences Beijing China School of Forestry and Wildlife Sciences Auburn University Auburn Alabama USA College of Arts and Sciences of beijing Union university Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2000 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

In flight MTF monitoring and compensation for CCD camera on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2,3, LI Xiaoying1,2,4. MIN Xiangjun5, YU Tao1,2, SUN Jijuan5, ZENG Yong1,2,4. XU Hua1,2 & GUO Ding2,6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal university, beijing 100101, china 2. The Center for National Spaceborne Demonstration, beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84.14.Avignon, France 4. graduate university of Chinese Academy of Sciences, beijing 100039, china 5. china Center for Resource Satellite Data and Application, beijing 100830, china 6. university of Electronic Science and Technology of china, Chengdu 610054. china State Key Laboratory of Remote Sensing Science Beijing Normal University Chinese Academy of Sciences Beijing 100101 China Center for National Spaceborne Demonstration Beijing 100101 China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France graduate university Chinese Academy of Sciences Beijing 100039 China china Center for Resource Satellite Data and Application Beijing 100830 China university of Electronic Science and Technology of china Chengdu 610054 China

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5 for 4.° directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 4.° axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3 , HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4., ZHANG Shu 2 & ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, beijing 100012, china 2 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, beijing 10004., china 3 {4. university of the Chinese Academy of Sciences, beijing 10004., china 4.Department of Physics, Nanjing Normal university, Nanjing 210011, china Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China graduate university of the Chinese Academy of Sciences Beijing China Department of Physics Nanjing Normal University Nanjing China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Nitric oxide modulates hypoxic pulmonary smooth muscle cell proliferation and apoptosis by regulating carbon monoxide pathway

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Acta Pharmacologica Sinica 2007年第1期28卷 28-35页

作者： Yan-fei WANG~2 Hong TIAN~2 Chao-shu TANG~(3,4. Hong-fang JIN~2 Jun-bao DU~(2,4.5)2 Department of Pediatrics,Peking university First Hospital,beijing 100034.china 3 Institute of Cardiovascular Diseases,Peking university First Hospital,beijing 100034.china,4.Key Laboratory of Molecular Cardiovascular Diseases,Ministry of Education,beijing 100034.china Department of Pediatrics Peking University First Hospital Beijing China Institute of Cardiovascular Diseases Peking University First Hospital Beijing China Key Laboratory of Molecular Cardiovascular Diseases Ministry of Education Beijing China

Aim:To explore the role of carbon monoxide(CO)in the regulation of hypoxicpulmonary artery smooth muscle cell(PASMC)proliferation and apoptosis bynitric oxide(NO).Methods:PASMC of Wistar rats was cultured in vitro in thepresence of a NO donor,sodium nitroprusside,or an inhibitor of heine oxygenase(HO),zinc protoporphyrin-IX,or under both normoxic and hypoxic *** and carboxyhemoglobin in PASMC medium were detected *** proliferating and apoptotic percentage of PASMC wasmeasured by flow *** expression of HO-1 mRNA in PASMC wasanalyzed by fluorescent real-time quantitative PCR,and the proliferating cell nuclearantigen and caspase-3 were examined by immunocytochemical ***:The results showed that hypoxia suppressed NO generation from PASMC,whichpromoted hypoxic PASMC proliferation and induced ***,hy-poxia induced HO-1 expression in PASMC and promoted CO production fromPASMC,which inhibited PASMC proliferation and regulated PASMC *** upregulated the expression of HO-1 mRNA in hypoxic PASMC;NO also inhib-ited proliferation and promoted apoptosis of hypoxic PASMC,possibly by regu-lating the production of ***:The results indicated that CO couldinhibit proliferation and regulate apoptosis of PASMC,and NO inhibited prolifera-tion and promoted apoptosis of hypoxic PASMC,possibly by regulating the pro-duction of CO.

关键词： hypoxia proliferation apoptosis carbon monoxide nitric oxide

Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley

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Science china Earth Sciences 2008年第7期51卷 1021-1035页

作者： LIU YunYun1,2,3 & DING YiHui2 1 Chinese Academy of Meteorological Sciences, beijing 100081, china 2 National Climate Center, beijing 100081, china 3 {4. university of Chinese Academy of Sciences, beijing 10004., china Chinese Academy of Meteorological Sciences Beijing China National Climate Center Beijing China graduate university of Chinese Academy of Sciences Beijing China

Based on the Indian and Chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern china. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South china Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion

关键词： Indian summer monsoon (ISM) the Meiyu over the Yangtze River Valley teleconnection mode

The identity of some taxa of Schizophragma (Saxifragaceae)

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Journal of Systematics and Evolution 2009年第2期47卷 151-161页

作者： 1,2Wei LIU 1Xiang-Yun ZHU 1(Institute of Botany,Chinese Academy of Sciences,beijing 100093,china) 2.graduate university of Chinese Academy of Sciences,beijing 10004.,china) Institute of Botany Chinese Academy of Sciences Beijing 100093 China graduate university of Chinese Academy of Sciences Beijing 100049 China

After examining a large number of type and authoritative specimens of Schizophragma Siebold & Zucc.,*** *** and *** *** Rehder were reduced to synonyms of *** Rehder and *** *** *** was reduced to synonym of *** *** crassum *** *** was treated as the correct name of *** ***(Chun) *** name *** *** Rehder is *** taxonomic treat-ment is supported by leaf epidermal characters.

关键词： leaf epidermis new synonym reinstatement Schizophragma

Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4.PG, in tumor cells

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Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2,4., Fan LIAO~(2,4., Chang-qi ZHAO~2, Yong-da LIN~2, Ming-xue ZUO~(2,3,5) ~2 College of Life Sciences, beijing Normal university, beijing 100875 china ~3 Key Laboratory for Molecular Biology and Gene Engineering Drugs of beijing, beijing 100875, china College of Life Sciences Beijing Normal University Beijing China Key Laboratory for Molecular Biology and Gene Engineering Drugs of beijing Beijing China

Aim: To define the in vitro cytotoxic activities of 4.demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4.PG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3 were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4.PG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562 cell lines）. For the K562 cell line, the antiproliferation effect of 4.PG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4.PG vs 2.23x 10（-5） mol/L for etoposide). Further, 4.PG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3 were confirmed in cells treated with 4.PG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4.PG. Conclusion: The cytotoxicity of 4.PG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4.PG to be a potential antitumor drug.

关键词： 4.demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth Sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4.1. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 2. Institute of Geophysics, china Seismological Bureau, beijing 100085, china 3. Institute of Deposition Resource, Chinese Academy of Geosciences, beijing 100037, china 4. School of Exploration and Information, china university of Geosciences, beijing 100083, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Institute of Geophysics China Seismological Bureau Beijing China Institute of Deposition Resource Chinese Academy of Geosciences Beijing China School of Exploration and Information China University of Geosciences Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 4. km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.