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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 {2. of Sciences, Wuhan 43.077, china 2. {3. school of the chinese {2. of Sciences, Beijing 100039, china 3. Unite Center for Astro-geodymics Research, chinese {2. of Sciences, Shanghai 2.003., china 1. Institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. graduate school of the {2. {3. 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 2.0 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

Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1,2.*, YUAN Yunbin1, OU Jikun1 and CHEN Jinping3.1. Institute of Geodesy and Geophysics, chinese {2. of Sciences, Wuhan 43.077, china 2. {3. school of chinese {2. of Sciences, Beijing 100039, china 3. Department of Precision Instrument and Mechanology, Tsinghua University, Beijing 100084, china) Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China graduate school of {2. {3. of Sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS ionospheric eclipse factor ionospheric influence factor

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science china Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3.1. Institute of Oceanology, chinese {2. of Sciences, Qingdao 2.6071, china 2. Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061, china 3. graduate school of the chinese {2. of Sciences, Beijing 100039, china 1. Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration 266061 Qingdao China 2. Institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. graduate {2. of the chinese {3. of Sciences 100039 Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Analysis of tandem repeats in the genome of chinese shrimp Fenneropenaeus chinensis

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chinese Science Bulletin 2005年第14期50卷 1462-1469页

作者： KONG Jie1 & GAO Huan2.3.1. Key Laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, chinese {2. of Fishery Sciences, Qingdao 2.6071, china 2. Institute of Oceanology, chinese {2. of Sciences, Qingdao 2.6071, china 3. The graduate school of the chinese {2. of Sciences, Beijing {12., china Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheris Research Institute Chinese Academy of Fishery Sciences Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China The graduate school of the {2. {3. of Sciences Beijing China

Through random sequencing, we found a total of 884000 base-pairs (bp) of random genomic sequences in the genome of chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2.59 tandem repeats were found, in which there were 1714 mi- crosatellites and 445 minisatellites, accounting for 79.4% and 2..6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2. of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.42.. In decreasing order, the 2. most abundant repeat sequence classes were as follows: AT (557), AC (471), AG (2.4), AAT (92., A (56), AAG (2.), ATC (2.), ATAG (2.), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them.

关键词：虾遗传特性遗传基因 DNA

Cloning and expression of putative ethylene receptor genes in soybean plant

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Progress in Natural Science:Materials International 2007年第10期17卷 1152-1160页

作者： Xie Zongming1,2.3. Lei Gang1,2. Wuriyanghan Hada1,2. Tian Aiguo1, Zhang Jinsong1 and Chen Shouyi1(1. National Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, chinese {2. of Sciences, Beijing 100101, china 2. {3. school of chinese {2. of Sciences, Beijing 100039, china 3. Xinjiang {2. of Agricultural and Reclamation Science, Shihezi 83.000, china) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China graduate school of {2. {3. of Sciences Beijing 100039 China Xinjiang academy of Agricultural and Reclamation Science Shihezi 832000 China

Ethylene plays important roles in plant growth, development, and stress responses, and ethylene receptors have been identified and studied extensively in various plant species. Here we report the cloning of four ethylene receptor genes from soybean, i.e. GmETR1, GmERS1, GmETR2.and GmEIN4. Construction of the phylogenic tree showed that GmETR1 and GmERS1 belong to subfamily I whereas GmETR2.and GmEIN4 belong to subfamily II. The four ethylene receptor genes showed different tissue-specific expression patterns in roots, stems, leaves, cotyledons, flowers, pods and seeds of soybean. These genes were differentially regulated by various abiotic stresses and plant hormones. The possible roles of the four genes in soybean plant were also discussed.

关键词： abiotic stress expression analysis ethylene receptor plant hormone soybean.

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2.3., LI Xiao-wei 2.3.. {2. of Information Engineering, Zhejiang Forestry College, Hangzhou 3.13.0, Zhejiang, china 2. Institute of Computing Technology, chinese {3. of Sciences, Beijing 100080, china 3. graduate {2. of the chinese {3. of Sciences, Beijing 100039, china school of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1,2.**, ZHANG Hongfu~1, XIAO Yan~ 1,2.and ZHAO Xinmiao~ 1,2.(1. State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, chinese academy of Sciences, Beijing 10002.,{2. 2. {3. school of chinese academy of Sciences, Beijing 100039,{2.) [a]State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China [b]graduate school of {2. {3. of Sciences Beijing China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1%. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.

Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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Science china Earth Sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2. ZHOU Jie1, SHEN Ji3. CHEN Peng1,2. WU Feng1,2.& XIE Xiuping1,2.1. State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, chinese {2. of Sciences, Xi’an 710075, china 2. {3. University of chinese {2. of Sciences, Beijing 100039, china 3. Nanjing Institute of Geography and Limnology, chinese {2. of Sciences, Nanjing 2.0008, china 1. State Key Lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. graduate University of chinese {2. of Sciences Beijing 100039 China 3. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3., grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3.and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1,2., GUO Qionglin~1**, HU Wei~1, WANG Yaping~1 and ZHU Zuoyan~1(1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, chinese academy of Sciences, Wuhan 4{2.072. china 2. {{2. school of chinese academy of Sciences, Beijing 100039, china) [a]State key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China China [b]graduate school of {2. {3. of sciences Beijing China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2.year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1806 nucleotides is translated into a putative peptide of 602.amino acids, including an extracellular ligand-binding domain of 2.4 amino acids (aa), a single transmembrane domain of 2. aa and an intracellular signal-transduction domain of 3.4 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2.year common carp, a 2.4 bp product was identified in liver and a 3.1 bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 3.1 bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2.year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2.year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.