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A study of a sequence of blazars from FSRQs to BL Lac objects

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 231-234页

作者： LIU HongTao1 & Chen Liang1,2 1 National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,China 2 graduate university of the chinese academy of sciences,Beijing 100049,China National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China graduate university of the chinese academy of sciences Beijing China

There are significant correlations between the broad line region luminosity LBLR,the quantity Δmax(maximum of Δ≡log[(Fν)cm/(Fν)mm]) and redshift *** are strong correlations between the extended radio luminosity PE,LBLR and Δ*** results indicate that FSRQs with higher mass accretion rate M and black hole spin j occur in the earlier,highly luminous,violent phase of the galactic sequence,and BL Lacs with lower M and j occur in the lower luminous,later phase of the galactic sequence,while FR II BL Lacs are possible intermediate stages in the sequence of blazars from FSRQs to FR I BL Lacs with j lower than FR II BL *** is indicated that there is a disk-jet symbiosis in blazars.

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

Preliminary results of a regional air-sea coupled model over East Asia

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chinese Science Bulletin 2010年第21期55卷 2295-2305页

作者： LI Tao ZHOU GuangQing Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China graduate university of the chinese academy of sciences Beijing 100049 China

We have established a regional air-sea coupled model over East Asia and conducted a 20-year integration to evaluate its performance in reproducing the present *** coupled model consists of RegCM3 and HYCOM controlled by the OASIS3 coupler with resuolution of 60 km for the atmosphere and 33 km for the ocean,*** some other regional air-sea coupled models,a one-way nesting method is employed in the oceanic component and a heat flux adjustment for solar radiation is used to remove an about 2°C cold bias in *** primary analysis for this 20-year integration shows that the coupled model successfully reproduces the main features of the circulations over East Asia,both in the atmosphere and the ocean,including climatology,seasonal and interannual *** are seen in the coupled model compared to the uncoupled one,especially in the simulation of precipitation,the most important element of the East Asian monsoon,although there are still obvious discrepancies that come mainly from the model components *** analyses show that the rainfall simulation benefits from the enhancements of the Northwest Pacific Subtropical High in summer,which leads to the improvement of the moisture flux simula-tion at the middle-lower atmospheric *** results indicate that the regional air-sea coupled model is more suitable for the East Asia monsoon simulation.

关键词：海气耦合模式东亚地区空气西北太平洋副高大气环流海域耦合模型模拟降雨

Bioreducible crosslinked low molecular weight branched PEI-PBLG as an efficient gene carrier

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Science China Chemistry 2010年第12期53卷 2490-2496页

作者： GUO ZhaoPei 1,TIAN HuaYu 1,XIA JiaLiang 1,2,CHEN Jie 1,LIN Lin 1 & CHEN XueSi 1 1 Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry,chinese academy of sciences,Changchun 130022,China 2 graduate university of chinese academy of sciences,Beijing 100049,China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China graduate university of chinese academy of sciences Beijing China

Low molecular weight polyethylenimine-poly(gamma-benzyl L-glutamate) (PEI-PBLG) was crosslinked by N,N'-cystaminebisacrylamide (CBA) to get the polymer named as CBA-PEI-PBLG (CPP).CPP not only inherits PEI-PBLG's amphiphilic advantages,but also possesses reducible *** can complex with DNA to form ***/DNA complex particles were characterized by particle size and zeta potential *** result showed that the complex particles have suitable size and surface charges for gene *** gel retardation assay also prove CBA-PEI-PBLG has proper condensing ability for *** has good reducible property,and also has good biocompatibility because of introducing PBLG *** cytotoxicity of CPP was evaluated using MTT assay,and the results showed CPP has lower cytotoxicity compared with PEI 25 *** transfection properties were characterized in different cells by using plasmid DNA as a *** showed higher transfection efficiencies and lower cytotoxicity in HeLa *** was attributed to bioreducible and biocompatibility properties of the *** results suggested that CPP is a promising low-toxic,highly effective non-viral gene carrier.

关键词： gene carrier transfection cytotoxicity crosslinked

Lunar surface dielectric constant,regolith thickness, and ~3He abundance distributions retrieved from the microwave brightness temperatures of CE-1 Lunar Microwave Sounder

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Science China Earth sciences 2010年第9期53卷 1365-1378页

作者： WANG ZhenZhan1, LI Yun1,2, JIANG JingShan1 & LI DiHui1 1 National Microwave Remote Sensing Laboratory, Center for Space Science and Applied Research, chinese academy of sciences, Beijing 100190, China 2 graduate university of chinese academy of sciences, Beijing 100049, China National Microwave Remote Sensing Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

Lunar regolith parameters, such as physical temperature, thickness and dielectric constant, are important in studying regolith features, distribution of lunar resources and evolution of the Moon. There had been no measurement obtained by lunar-orbit-borne microwave radiometer applied to evaluate the properties of lunar regolith before CE-1 Lunar Microwave Sounder (CELMS) being launched. CEMLS is the first passive microwave radiometer in the world to sound the surface of the Moon. The brightness temperatures (TB) sensed by CELMS include complicated information on the above geophysical parameters. In this paper, algorithms of retrieving dielectric constant, regolith thickness, and 3He content from CELMS brightness temperatures are developed, and the results are compared with those from literature. The results show that the regolith thicknesses are mostly in the range of 4.0-6.0 m, and 43% of them are bigger than 5.0 m. The content of 3He evaluated by retrieved regolith thickness is about 1.03 million tons.

关键词： CE-1 Lunar Microwave Sounder (CELMS) lunar regolith dielectric constant lunar regolith thickness 3He retrieval

TIME-IGGCAS model validation:Comparisons with empirical models and observations

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Science China Technological sciences 2008年第3期51卷 308-322页

作者： YUE XinAn1,2,3, WAN WeiXing1, LIU LiBo1, NING BaiQi1, ZHAO BiQiang1 & ZHANG ManLian1 1 Institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, China 2 Wuhan Institute of Physics and Mathematics, chinese academy of sciences, Wuhan 430071, China 3 graduate university, chinese academy of sciences, Beijing 100049, China Institute of Geology and Geophysics Chinese Academy of Sciences

The TIME-IGGCAS (Theoretical Ionospheric Model of the Earth in Institute of Ge- ology and Geophysics, chinese academy of sciences) has been developed re- cently on the basis of previous works. To test its validity, we have made compari- sons of model results with other typical empirical ionospheric models (IRI, NeQuick-ITUR, and TItheridge temperature models) and multi-observations (GPS, Ionosondes, Topex, DMSP, FORMOSAT, and CHAMP) in this paper. Several conclu- sions are obtained from our comparisons. The modeled electron density and elec- tron and ion temperatures are quantitatively in good agreement with those of em- pirical models and observations. TIME-IGGCAS can model the electron density variations versus several factors such as local time, latitude, and season very well and can reproduce most anomalistic features of ionosphere including equatorial anomaly, winter anomaly, and semiannual anomaly. These results imply a good base for the development of ionospheric data assimilation model in the future. TIME-IGGCAS underestimates electron temperature and overestimates ion tem- perature in comparison with either empirical models or observations. The model results have relatively large deviations near sunrise time and sunset time and at the low altitudes. These results give us a reference to improve the model and enhance its performance in the future.

关键词： ionosphere theoretical model empirical model satellite observation relative deviation

Functional analysis of schistosomes EF-hand domain-containing tegument proteins

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chinese Science Bulletin 2007年第15期52卷 2100-2107页

作者： YU FuDong1,2,3,KANG Bin1,3,LI YuanYuan3,4 & LI YiXue1,3 1 Bioinformatics Center,Key Laboratory of Systems Biology,Shanghai Institutes for Biological sciences,chinese academy of Sci-ences,Shanghai 200031,China 2 graduate university of chinese academy of sciences,Shanghai 200031,China 3 Shanghai Center for Bioinformation Technology,Shanghai 200235,China 4 Key Laboratory of Systems Biology,Shanghai Institutes for Biological sciences,chinese academy of sciences,Shanghai 200031,China Bioinformatics Center Key Laboratory of Systems Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

Schistosomes cause schistosomiasis disease which severely threatens human health. Little is known about the functions of EF-hand domain containing schistosomes tegument proteins other than as an-tigens. More possible functions of these tegument proteins were investigated with in silico analyses including protein-protein functional interaction,site-specific variation and glycosylation modification. The analysis results suggested that schistosomes could actively modulate host immune responses for its own favor through functional interactions with host proteins with immunomodulatory function,and passively regulate host immune responses through sequence variation under positive selection and glycosylating the recognition sites of host immune attack. In addition,the analysis of the C-terminal domain of these tegument proteins indicated that they could assist schistosomes in escaping host immune attacks through inhibiting chemotaxis and non-complement fixing antibody (IgG4) responses. In summary,our results suggested that these tegument antigen proteins could assist schistosomes in escaping and modulating host immune responses for self-protection during the process of host-para-site interaction.

关键词：寄生虫血吸虫皮蛋白质健康

GIS-based analysis of forest degradations in Baihe Forestry Bureau,northeast China

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Science China(Technological sciences) 2006年第z1期49卷 167-176页

作者： ZHOU Li, DAI Limin , Guofan Shao, XU Dong, WANG Hui & BAI Jianwei Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, China graduate university of chinese academy of sciences, Beijing 100101, China Department of Forestry and Natural Resources, Purdue university, West Lafayette, IN 47907, USA Department of City Development, Jinan university, Jinan 250002, China academy of Forest Inventory and Planning, State Forestry Administration, Beijing 100714, China Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe Forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy Forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed Forest, the native forest vegetation type, decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed Forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented.

关键词： geographic information system, forest management, Changbai Mountains, forest change, forest decline.

Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications

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chinese Science Bulletin 2010年第15期55卷 1483-1487页

作者： GE JunYi 1,2 & GUO ZhengTang 3 1 State Key Laboratory of Loess and Quaternary Geology (SKLLQG),Institute of Earth Environment,chinese academy of sciences,Xi’an 710075,China 2 graduate university of chinese academy of sciences,Beijing 100049,China 3 Key Laboratory of Cenozoic Geology and Environment,Institute of Geology and Geophysics,chinese academy of sciences,Beijing 100029,China State Key Laboratory of Loess and Quaternary Geology (SKLLQG) Institute of Earth Environment Chinese Academy of Sciences Xi’an China graduate university of chinese academy of sciences Beijing China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The Qinling Mountains constitute a key climate barrier between southern and northern *** recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West ***-mammalian fossils dated a 150.2 m section (NL-VI) near Xihe for the late Miocene to Pliocene (～10-4 Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2 m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope *** results add important insights to the earlier studies about the widespread eolian deposition in northern China during the Miocene,prior to 8 *** also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ～10 *** well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene.

关键词：秦岭山脉风尘堆积构造意义气候新近纪晚中新世地球化学分析风尘沉积

Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU Jin (Department of Bioengineering, School of Chemical and Environmental Engineering, China university of Mining and Technology (Beijing), Beijing 100083, China Department of Biology, graduate university of chinese academy of sciences, Beijing 100049, China) Department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China. Department of Biology Graduate University of Chinese Academy of Sciences Beijing 100049 China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.