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Comparative study on the effect of integrin αvβ3 on secretion of matrix metalloproteinases in human normal and carcinoma trophoblasts

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Progress in Natural Science:materials international 2005年第11期15卷 982-987页

作者： BAI Suxia, FU Yayuan, KONG Gang and WANG Yanling (State Key Laboratory of Reproductive Biology, Institute of Zoology, chinese academy of sciences, Beijing 100080, china The Second Hospital of chinese Medicine College, shenyang 110003, china) State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. The Second Hospital of chinese Medicine College Shenyang 110003 China

The invasion of cytotrophoblast cells into the maternal endometrium during embryonic implantation is very similar to the metastasis of carcinoma cells. However, the significant difference is that the former is a highly controlled process. In this report, the effects of integnn αvβ3 on the secretion of matrix metalloproteinase (MMP) were compared between normal cytotrophoblast cells and chorio-carcinoma cells by RT-PCR, gelatin zymography and immunocytochemistry. The results reveal that both normal cytotrophobiast cells and choriocarcinoma cells can express integrin αvβ3. The secretion of MMPs in normal cytotrophoblast cells is up-regulated by anti-αvβ3 antibody, whereas, decreased in choriocarcmoma cells. It was suggested that αvβ3 can modulate the expression of MMPs in trophoblasts, and this action is carried out through distinct mechanisms in normal and carcinoma cytotrophoblast cells.

关键词： cytotrophoblast cells choriocarcinoma cells integrfn αvβ3 matrix metalloproteinase.

Stabilization effects of third element on CaCu5 type derivatives of rare-earth transition-metal intermetallics

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Progress in Natural Science:materials international 2002年第2期 3-12页

作者： LIANG Jingkui, LIU Quanlin, HUANG Feng, RAO Guanghui and CHEN Xiaolong( Institute of physics and center for Condensed Matter physics, chinese academy of sciences, Beijing 100080, china international center of Material physics, chinese academy of sciences, shenyang 110015, china)

Part of the results of the key project "Search for novel rare-earth functional materials" supported by the National Natural Science Foundation of china is reviewed. In combination with reports in literature, the effects of the third element M on the formation and stability of La2(Co, M)17, R(Fe, M)12 and R3(Fe, M)29 intermetallic compounds are discussed by considering mixing enthalpy of M with rare-earth, Fe and Co, and atomic radius, electronegativity and electronic configurations, etc. It is concluded that the mixing enthalpy and atomic radius dominate the preferential sites and the minimum amount of M required to stabilize a structure, which ultimately affect the magnetic properties of a compound prominently. This review should provide some heuristic hints for exploiting novel rare-earth transition metal functional materials and for improving their performance.

关键词： La2(Co M)17 R(Fe M)12 Rs(Fe M)29 crystal structure magnetic properties.

First-principles study of the effects of Si doping on geometric and electronic structure of closed carbon nanotube

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Science Bulletin 2005年第17期 9-14页

作者： ZHOU Junzhe1 & WANG Chongyu1, 2 1. Department of physics, Tsinghua University, Beijing 100084, china 2. international Centre for materials physics, chinese academy of Sci-ences, shenyang 110016, china

The effects of Si doping on geometric and elec-tronic structure of closed carbon nanotube (CNT) are stud-ied by, a first-principles method, DMol. It is found that the local density of states at the Fermi level (EF) increases due to the Si-doping and the non-occupied states above the EF go down toward the lower energy range under an external elec-tronic field. In addition, due to the doping of Si, a sub-tip on the CNT cap is formed, which consisted of the Si atom and its neighbor C atoms. From these results it is concluded that Si-doping is beneficial to the CNT field emission properties.

关键词： carbon nanotube doping electronic structure field emission.

Diagnostic analysis of mesoscale rainstorms in the Jiang-Huai valley of china with convective vorticity vector

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Progress in Natural Science:materials international 2007年第5期17卷 559-568页

作者： Cui Xiaopeng, Gao Shouting and Li Xiaofan (Laboratory of Cloud-Precipitation physics and Severe Storms (LACS), Institute of Atmospheric physics, chinese academy of sciences, Beijing 100029, china Joint center for Satellite Data Assimilation and NOAA/NESDIS/center for Satellite Applications and Research, Camp Springs, Maryland, USA) [a]Laboratory of Cloud-Precipitation physics and Severe Storms (LACS) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China [b]Joint center for Satellite Data Assimilation and NOAA/NESDIS/center for Satellite Applications and ResearchCamp Springs Maryland USA

By the vector product of absolute vorticity vectors and equivalent potential temperature gradients, a new vector, convec-tive vorticity vector (CVV) is readdressed after Gao et al., and is applied to the study of the development and movement of mesoscale rainstorms in the Jiang-Huai valley of china by using high-resolution simulation data with PSU/NCAR MM5 briefly. The results show that the CVV, especially its vertical component which is closely related to interactions between vertical secondary circulations and horizontal equivalent potential temperature gradients, may be a good tracer and diagnostic tool in the study of mesoscale rainstorms in the Jiang-Huai valley of china. And the main physical processes responsible for the variations of the vertical component of the CVV are discussed briefly based on its tendency equation proposed in this article.

关键词： convective vorticity vector mesoscale rainstorms tendency equations.

A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation

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Journal of materials Science & Technology 1999年第5期15卷 435-438页

作者： Qiang LI and Yongbo XU(State Key Laboratory for Fatigue and Fracture of materials, Institute of Metal Research, chinese academy of sciences,shenyang 110015, china) To whom correspondence should be addressed Present address: Analysis Cener, School of Mater State Key Laboratory for Fatigue and Fracture of materials Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China Analysis Cener School of Materials Tianjin University Tianjin 300072 China international center of materials physics Chinese Academy of Sciences Shenyang 110015 China Laboratory for Non-linear Mechanics of Continuous Media Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Recrystallized grains, less than 200 nm in diameter were observed in heavily shear zones of a high strength low alloy steel and a Ni-based alloy, and Also grain refinement, less than 3 μm in diameter was made in high purity aluminum by ECAE at ambient temperature. The experimental results showed that high strain rate and large deformation could induce dynamic *** on dislocation dynamics and grain orientation change enhanced by plastic deformation,a model for the recrystallization process is developed. The model is used to explain the ultra fine grains which are formed at a temperature still much lower than that for the conventional recrystallization

关键词： Figure A Model of Dynamic Recrystallization in Alloys during High Strain Plastic Deformation

维普期刊数据库

Recent progress in fingerprint recognition

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Progress in Natural Science:materials international 2006年第3期16卷 231-240页

作者： TIAN Jie, CHEN Xinjian, ZHANG Yangyang, YANG Xin, HE Yuliang, LI Liang, XIE Weihua and ZHENG Zhipeng (center for Biometrics and Security Research, Key Laboratory of Complex Systems and Intelligence Science, Institute of Automation, chinese academy of sciences, Beijing 100080, china Graduate School of the chinese academy of sciences, Beijing 100080, china) [a]center for Biometrics and Security Research Key Laboratory of Complex Systems and Intelligence Science Institute of Automation Chinese Academy of Sciences Beijing China [b]Graduate School of the chinese academy of sciences Beijing China

Fingerprint recognition has been increasingly used to realize personal identification in civilian' s daily life, such as ID card, fingerprints hard disk and so on. Great improvement has been achieved in the on-line fingerprint sensing technology and automatic fingerprint recognition algorithms. Various fingerprint recognition techniques, including fingerprint acquisition, classification, enhancement and matching, are highly improved. This paper overviews recent advances in fingerprint recognition and summarizes the algorithm proposed for every step with special focuses on the enhancement of low-quality fingerprints and the matching of the distorted fingerprint images. Both issues are believed to be significant and challenging tasks. In addition, we also discuss the common evaluation for the fingerprint recognition algorithm of the Fingerprint Verification Competition 2004 (FVC2004) and the Fingerprint Vendor Technology Evaluation 2003 (FpVTE2003), based on which we could measure the performance of the recognition algorithm objectively and uniformly.

关键词： biometrics fingerprint enhancement matching minutia image registration similarity measures.

Contribution of cloud condensate to surface rainfall process

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Progress in Natural Science:materials international 2006年第9期16卷 967-973页

作者： ZHOU Yushu , GUI Xiaopeng and LI Xiaofan ( Institute of Atmospheric physics, chinese academy of sciences, Beijing 100029, china Joint center for Satellite Data Assimilation and NOAA/NESDIS/Office of Research and Applications Camp Springs, Maryland, USA) [a]chinese academy of sciences Institute of Atmospheric Physics Beijing China [b]Joint center for Satellite Data Assimilation and NOAA/NESDIS/Office of Research and Applications Camp Springs Maryland USA

Contribution of cloud condensate to surface rainfall processes is investigated in a life span of tropical convection based on hourly data from a two-dimensional cloud resolving simulation. The model is forced by the large-scale vertical velocity, zonal wind and horizontal advections obtained from tropical ocean global atmosphere coupled ocean-atmosphere response experiment (TOGA COARE). The results show that during the genesis, development, and decay of tropical convection, calculations with water vapor overestimate surface rain rate, and cloud condensate plays an important role in correcting overestimation in surface rain rates. The analysis is carried out in deep convective clouds and anvil clouds during the development of tropical convection. The surface rain rates calculated with water vapor in deep convective clouds and anvil clouds have similar magnitudes, the large surface rain rate appears in deep convective clouds due to the consumption of water hydrometeors whereas the small surface rain rate occurs in anvil clouds because of the gain of ice hydrometeors. Further analysis of the grid data shows that the surface rain rates calculated with water vapor and with cloud condensate are negatively correlated with the correlation coefficient of - 0.85, and the surface rain rate calculated with cloud condensate is mainly contributed to the water hydrometeors in the tropical deep convective regime.

关键词： cloud condensate surface rain rate cloud resolving simulation.

Progress in multi-waveband observations of supernova remnants

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Progress in Natural Science:materials international 2008年第9期18卷 1057-1062页

作者： Xuejuan Yang a,b, Fangjun Lua, Wenwu Tian c,d,* a Particle Astrophysics center, Institute of High Energy physics, chinese academy of sciences, Beijing 100049, china b Department of Astronomy, Beijing Normal University, Beijing 100875, china c National Astronomical Observatories, chinese academy of sciences, 20A Datun Road, Chaoyang District, CAS, Beijing 100012, china d Department of physics & Astronomy, University of Calgary, Alberta, Canada T2N 1N4 Particle Astrophysics center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences 20A Datun Road Chaoyang District CAS Beijing 100012 China Department of physics & Astronomy University of Calgary Alberta Canada T2N 1N4

The development of observational techniques has enriched our knowledge of supernova remnants. In this paper, we review the main progresses in the last decade, including new discoveries of supernova remnants and the associated (rare type of) pulsars, nucleosynthesis, the interaction between supernova remnants and molecular clouds, dust in the supernova remnants, shock physics, and cosmic ray accelerations.

关键词： Supernova remnant Observations

Interannual variation of annual precipitation and urban effect on precipitation in the Beijing region

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Progress in Natural Science:materials international 2007年第9期17卷 1042-1050页

作者： Yu Shuqiu(State Key Laboratory on Severe Weather,chinese academy of Meteorological sciences,Beijing 100081,china) State Key Laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081， China

The large scale character of the interannual variation of precipitation and the urban effect on local annual precipitation anomaly are investigated in this paper based on the 1960-2000 annual precipitation observations at 20 stations in the Beijing *** results show that:the annual precipitation in the Beijing region possesses the large scale variation character with the linear trend of-1.197/10 yr,which corresponds to a total reduction of 27.82 mm in annual precipitation in the 41 years;the local annual precipitation anomalies(percent of the normal 1960-2000)show a positive center near the urban area,*** precipitation island(UPI),whose intensity increases with the linear trend of 0.6621%/10 yr,opposite to the interannual trend of large scale precipitation over the Beijing region;changes in the UPI are also associated with the intensity of synoptic processes of precipitation,and when the synoptic processes are strong(wet years),the intensity of UPI strengthens,while the synoptic processes are weak(dry years),and the UPI disappears in the Beijing region.

关键词： urban precipitation island effect interannual climate variation precipitation Beijing atmospheric science