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Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth Sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2 & LU Yang1,3.1. Institute of Geodesy and Geophysics, chinese academy of Sciences, Wuhan 43.077, china 2. {3. School of the chinese academy of Sciences, Beijing 10003., china 3. Unite Center for Astro-geodymics Research, chinese academy of Sciences, shanghai 20003., china 1. Institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. graduate School of the chinese academy of Sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 200 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3.& WANG Huijun2 1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of Sciences, Beijing 100029, china 2. Department of Atmospheric Science, Yunnan {3., Kunming 650091, china 3. graduate {3. of the chinese academy of Sciences, Beijing 100049, china 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. graduate university of the chinese {3. of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in Sichuan Basin:Taking Lezhi County as Example

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2, 3., LIU Qing 1 1. Chengdu Institute of Biology, chinese academy of Sciences, Chengdu 610041, Sichuan,china 2. {3. university of chinese academy of Sciences, Beijing 100049, china 3. academy of Land Reconnaissance and Layout of Sichuan Province , Chengdu 61003., Sichuan, china Chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan China graduate university of chinese {3. of Sciences Beijing China academy of Land Reconnaissance and Layout of Sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of china, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2001. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2001. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2001, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

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,{3.,china 2 graduate university of chinese academy of Sciences,{3.,china 3.shanghai Center for Bioinformation Technology,shanghai 20023.,china 4 Key Laboratory of Systems Biology,shanghai Institutes for Biological Sciences,chinese academy of Sciences,{3.,china Bioinformatics Center Key Laboratory of Systems Biology Shanghai Institutesfor 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

Sequence analysis of mRNA polyadenylation signals of rice genes

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chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2, GAO Chenxi1,2,3.& HAN Bin1,3.41. National Center for Gene Research, shanghai Institutes for Biological Sciences, chinese academy of Sciences, shanghai 20023., china 2. graduate School of the chinese academy of Sciences, Beijing 10003., china 3. Institute of Plant Physiology and Ecology, shanghai Institutes for Biological Sciences, chinese academy of Sciences, shanghai 20003., china National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China graduate School of the chinese academy of Sciences Beijing 100039 China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3.-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12969 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953.genes. The al- ternative poly(A) sites were revealed in approxi- mately 25% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3. fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3. fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3.and Xin-Wu Cao1,2 1 shanghai Astronomical Observatory, chinese academy of Sciences, {3., china 2 Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, {3., china 3.graduate School of the chinese academy of Sciences, Beijing 100049, china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate School of the chinese academy of Sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

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.graduate university of chinese academy of Sciences, Beijing 100049, china 1. chinese academy of Meteorological Sciences Beijing 100081 China 2. National Climate Center Beijing 100081 China 3. graduate university of chinese {3. of Sciences Beijing 100049 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

Strong decays of N~*(153.) in an extended chiral quark model

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3.& ZOU BingSong1,2,3.1 Institute of High Energy Physics,chinese academy of Sciences,Beijing 100049,china 2 Theoretical Physics Center for Science Facilities,chinese academy of Sciences,Beijing 100049,china 3.graduate university of chinese academy of Sciences,Beijing 100049,china Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China graduate university of chinese {3. of Sciences Beijing 100049 China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

Simulations for terrestrial planets formation

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 794-803页

作者： ZHANG Niu 1,2 &JI JiangHui 2,3.1graduate university of chinese {3. of Sciences,Beijing 100049,china 2Purple Mountain Observatory,chinese {3. of Sciences,Nanjing 210008,china 3.National Astronomical Observatories,chinese {3. of Sciences,Beijing 100012,china graduate university of chinese {3. of Sciences Beijing 100049 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

In this paper,the formation of terrestrial planets in the late stage of planetary formation is investigated using the two-planet *** that time,the protostar formed for about 3.Ma and the gas disk *** the model,the perturbations from Jupiter and Saturn are *** of the mass of outer planet,and the initial eccentricities and inclinations of embryos and planetesimals are also *** results show that,terrestrial planets are formed in 50 Ma,and the accretion rate is about 60%-80%.In each simulation,3.4 terrestrial planets are formed inside"Jupiter"with masses of 0.15 -3.6M⊕.In the 0.5-4 AU,when the eccentricities of planetesimals are excited,planetesimals are able to accrete material from wide radial *** plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this *** could also happen a few times between two major planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 10 8 *** one of our simulations,commensurability of the orbital periods of planets is very ***,a librating-circulating 3.2 configuration of mean motion resonance is found.

关键词： astrophysics exoplanet planetary formation n-body simulation