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Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern china

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Science china Earth Sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2.YI Yi1,HU Chaoyong1, CAI Yanjun3 & CHENG Hai4.1. Faculty of Earth Science,china University of Geosciences,{2. 4.0074.china 2. School of Environmental Studies,china University of Geosciences,{2. 4.0074.china 3. SKLLQG,institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,china 4. Department of Geology and Geophysics,University of Minnesota,MN554.5,USA 1. Faculty of Earth Science China University of Geosciences 430074 Wuhan China 2. School of Environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. Department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern china’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C1.1.to C2. in carbon number, maximizing at C1., with a second dominance at C2.. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C2.). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C1.:1./C1.:0, C1.:1.C1.:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2.ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

Second-order consensus in networks of dynamic agents with communication time-delays

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Journal of Systems Engineering and Electronics 2010年第1期21卷 88-94页

作者： Bo Yang1.2. Huajing Fang3, and Hua Wang4.1. School of Navigation, {1. University of Technology, {1. 4.0063, P. R. china 2. {1. Second Ship Design and Research {4., {1. 4.0064. P. R. china 3. Department of Control Science and Engineering, Huazhong University of Science and Technology, {1. 4.0074. P. R. china 4. Department of Aerospace and Mechanical Engineering, Boston University, Boston MA02.1., USA School of Navigation Wuhan University of Technology Wuhan 430063 P. R. China wuhan Second Ship Design and Research {1. Wuhan 430064 E R. China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China Department of Aerospace and Mechanical Engineering Boston University Boston MA02215 USA

This paper proposes second-order consensus protocols with time-delays and gives the measure of the robustness of the protocols to the time-delay existing in the network of agents with second-order dynamics. By employing a frequency domain method, it is proven that the information states and their time derivatives of all the agents in the network achieve consensus asymptotically, respectively, for appropriate communication timedelay if the topology of weighted network is connected. Particularly, a tight upper bound on the communication time-delay that can be tolerated in the dynamic network is found. The consensus protocols are distributed in the sense that each agent only needs information from its neighboring agents, which reduces the complexity of connections between neighboring agents significantly. Numerical simulation results are provided to demonstrate the effectiveness and the sharpness of the theoretical results for second-order consensus in networks in the presence of communication time-delays.

关键词： second-order consensus protocols dynamic networks algebraic graph theory frequency domain analysis com-munication constraints.

Warming in Arctic intermediate and deep waters around Chukchi Plateau and its adjacent regions in 1.99

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Science china Earth Sciences 2005年第8期48卷 1312-1320页

作者： ZHAO Jinping1. GAO Guoping2.& JIAO Yutian1.1. First institute of Oceanography, State Oceanic Administration, Qingdao 2.6061.{1. 2. Ocean University of{1., Qingdao 2.6003,{1. 1. First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. Ocean University of china 266003 Qingdao China

Based on the data measured during Arctic scientific expedition of china in 1.99, the characteristics of temperature and salinity distributions around the Chukchi Plateau and its ad-jacent regions have been studied. It was found that the intermediate water with temperature higher than 0.5℃ existed in all parts of a 6{1. km section with a maximum temperature of 0.85℃ indicating a strong signal of the warming in Arctic Intermediate Water in 1.99. Two important phenomena are described in this paper. First, the temperature of warm water was horizontally nonuniform. In the area of Chukchi Plateau, the temperature was higher, the layer of warm water was thicker and the depth of the warm water core was shallower than those in the area of con-tinental slope. The horizontal nonuniformity of the temperature distribution of warming water im-plies that the upward heat flux should also be nonuniform, thus exerting different effects on sea ice thickness, ice extent, and air-sea heat exchange. The mechanism to generate higher tem-perature in the plateau region was the bypassing of current around the plateau area caused by the special local topography, which restricted water exchange across the plateau and conserved heat in the water body. Second, the deep water down to 1.1.0 m was also warming with a tem-perature increase of 0.2.. The warming in deep water reflects the occurrence of complicated heat redistribution processes in the intermediate water, which altered the thermal structure in the upper 1.1.0 m. The warming data embody the obvious impact of global climate change on the Arctic Ocean and further studies are wanted.

关键词： Chukchi Plateau, Arctic Ocean, warming in intermediate water, warming in deep water.

U-Pb dating of zircon from the bed parallel anatectic granitic intrusion in the Baoban group in Hainan Island and the tectonic implication

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Science china Earth Sciences 2005年第12期48卷 2092-2103页

作者： DING Shijiang1. HU Jianmin2. SONG Biao3,4. CHEN Mulun1. XIE Shengzhou1.& FAN Yuan1.1. Geological Surveying {1. of Hainan, Haikou 5702.6, china 2. {1. of Geomechanics, Chinese Academy of Geological Sciences, Beijing 1.0081. china 3. Beijing Center of SHRIMP, Beijing 1.0037, china 4. {1. of Geology, Chinese Academy of Geological Sciences, Beijing 1.0037, china 1. Geological Surveying institute of Hainan 570206 Haikou China 2. institute of Geomechanics Chinese Academy of Geological Sciences 100081 Beijing China 3. Beijing Center of SHRIMP 100037 Beijing China 4. {1. of Geology Chinese Academy of Geological Sciences 100037 Beijing China

The petrological and geochemical features of the bed parallel granitic intrusion in the Pre-Cambrian Baoban group in Hainan Island attest to the anatexis origin of the granites. U-Pb dating analyses of zircons from the anatectic granite and the biotite two-feldspar gneiss in the Baoban group, using SHRIMP II in the Beijing Ion-probe Center, acquire 2.6Pb/2.8U ages of 368±3.5 Ma (of granite, 95% confidence level, MSDW=1.2.) and 362.9±6.1.Ma (of gneiss, 95% confidence level, MSDW = 2.0{2. respectively. The two late Devonian ages indicate consistently a tectonic- thermal event experienced in Hainan Island, and are the first discovered record of the Devonian geological process in the district. This event possibly resulted from the deep ther-mal-dynamic process when the Gondwana continent began to break up in the Devonian period.

关键词： Hainan Island, Devonian period, anatectic granite, zircon SHRIMP U-Pb dating.

Cloning and characterization of interferon stimulated genes Viperin and ISG1.,and their promoters from snakehead Channa argus

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Progress in Natural Science:Materials International 2007年第12期17卷 1425-1435页

作者： Jia Weizhang1.2. Zhou Xiuxia1.2. Huang Rong1.2.and Guo Qionglin1.1. institute of Hydrobiololgy, Chinese Academy of Sciences, {1. 4.0072. china 2. Graduate University of Chinese Academy of Sciences, Beijing 1.0039, china) institute of Hydrobiololgy Chinese Academy of Sciences Wuhan 430072 China Graduate University of Chinese Academy of Sciences Beijing 100039 China

By suppression subtractive hybridization, rapid amplification of cDNA ends and gene walking methods, interferon stimulated genes (ISGs), Viperin and ISG1., and their promoters have been cloned and characterized from snakehead Channa argus. The Viperin cDNA was found to be 1.0}{2.nt and contain an open reading frame (ORF) of 1.59 nt that translates into a putative peptide of 352.amino acid (aa). The putative peptide of Viperin shows high identity to that in teleosts and mammals except for the N-terminal 70 aa. The ISG1. cDNA was found to be 758 nt and contain an ORF of {2.8 nt that translates into a putative peptide of 1.5 aa. The putative peptide of ISG1. is composed of two tandem repeats of ubiquitin-like (UBL) domains, and a canonical conjugation motif (LRGG) at C-terminal. Viperin and ISG1. promoter regions were characterized by the presence of interferon stimulating response elements (ISRE) and γ-IFN activation sites (GAS). ISRE is a feature of IFN-induced gene promoter and partially overlaps interferon regulatory factor (IRF) 1.and IRF2.recognition sites. GAS is responsible for the γ-IFN mediated transcription. One conserved site for NF-κB was found in the promoter region of Viperin. This is the first report of conservative binding motif for NF-κB in accordance with the consensus sequence (GGGRNNYYCC) among teleost ISG promoters. Moreover, there were also TATA, CAAT and Sp1.transcription factor sites in Viperin and ISG1. promoters. In 5′ untranslated region (UTR), snakehead ISG1. gene contains a single intron, which differs from Viperin gene. The transcripts of Vipeirn and ISG1. mRNA were mainly expressed in head kidney, posterior kidney, spleen and gill. The expression levels in liver were found to increase obviously in response to induction by IFN-inducer poly I∶C.

关键词： interferon interferon stimulated gene (ISG) Viperin ISG1. snakehead (Channa argus).

Fabrication of Ni-decorated helical ribbon composite microstructure from self-assembled lipid tubule by electroless metallization

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Science china Chemistry 2006年第3期49卷 238-245页

作者： FU Yubin1.2. ZHANG Lide1.& ZHENG Jiyong2.1. institute of Solid State Physics,{1. Academy of Sciences, Hefei 2.0031.{1. 2. Luoyang Ship Material Research institute, Luoyang 4.1.39,{1. 1. institute of Solid State Physics China Academy of Sciences Hefei 230031 China 2. Luoyang Ship Material Research institute Luoyang 471039 China

Lipid molecules can self-assemble into a tubular structure, which is formed by tightly wound helical ribbons. Lipid tubules are utilized as a precursor to fabricate a novel Ni-decorated helical ribbon composite microstructure in a high yield by electroless deposition. The microstructure carries Ni nanoparticles on the flat face and wires at the edge of helical ribbon, in which the average size of nanoparticles is about 4.―60 nm, and the wires are of a layered structure strongly correlated with a multi-bilayer structure in the lipid membrane. Compared with the tubular precursor, the Ni-decorated composite microstructure becomes short and irregular shapes due to the breakage in the deposition, and its formation is largely bound up with the tubular helical structure and the different catalytic process. Finally, the helical composite microstructure would have a potential application in the development of electric active materials.

关键词： molecular self-assembly, lipid tubule, helical ribbon, electroless deposition, nanoparticles and wires, composite microstructure.

Sorption of Eu^(3+) onto nano-size silica-water interfaces

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Science china Earth Sciences 2005年第11期48卷 1942-1948页

作者： HU Ping1.2. YIN Xiulan3 , ZHAO Linghu1.& LI Dien{2.1. Department of Earth Sciences,{1. University of Geosciences, wuhan {2.007{2.{1. 2. Northeastern Illinois University, Chicago, IL 6062., USA 3.{1. {{2. of Geo-Environmental Monitoring, Beijing 1.0081.{1. {2. Division of Chemistry, Los Alamos National Laboratory, Los Alamos, NM 875{2., USA 1. Department of Earth Sciences China University of Geosciences 430074 Wuhan China 2. Northeastern Illinois University 60625 Chicago IL USA 3. china {1. of Geo-Environmental Monitoring 100081 Beijing China 4. Division of Chemistry Los Alamos National Laboratory 87544 Los Alamos NM USA

The sorption of Eu species onto nano-size silica-water interfaces is investigated at pH range of 1.8.5 and the initial Eu concentrations (CEu) of 2.× 1.?5, 2.× 1.?4.and 2.× 1.?3 M using fluorescence spectroscopy. The sorption rate of Eu is initially low, but significantly in-creases at pH > 4. For the initial CEu of 2.× 1.?5, 2.× 1.?4.and 2.× 1.?3 M, the dissolved Eu spe-cies are completely sorbed onto silica-water interfaces at pH = 4.75, ~5.8 and 6.6, respectively, with the respective sorption densities of ~1.58 × 1.?8, 1.58 × 1.?7 and 1.58 × 1.?6 mol/m2. The sorbed Eu species at pH 2. to ~6 at pH = 6. At pH = 6 – 8, Eu(OH)2., Eu(CO3)+ and Eu(CO3)2. form in the solutions, and Eu(CO3)+ is dominant at pH = ~7.5. These ions may be sorbed onto silica-water interfaces as inner-sphere bidentate complexes or multi-nuclear pre-cipitates.

关键词： surface sorption, Eu3+ species, nano-size silica, fluorescence spectroscopy, immobilization of toxic metals

Biasing fluctuation model for directional stepping motion of molecular motor

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Chinese Science Bulletin 1998年第22期43卷 1879-1882页

作者： BAO Jingdong 1.and ZHUO Yizhong 2.1. Beijing Meteorological College, Beijing 1.0081. china 2. china institute of Atomic Energy, Beijing 1.2.8}3, china Beijing Meteorological College Beijing China china {1. of Atomic Energy Beijing China

The biasing fluctuation model with a colored noise is presented to study the directional stepping motion of the molecular motor. The expression of probability current is obtained in the adiabatic approximation. The fo... 详细信息

关键词： molecular motor stepping motion biasing force colored noise Langevin equation.

The deformation pattern and fault rate in the Tianshan Mountains inferred from GPS observations

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Science china Earth Sciences 2008年第8期51卷 1064-1080页

作者： YANG ShaoMin1.2. LI Jie1.3 & WANG Qi2.1.1.Research Center of Space Science and Technology, china University of Geosciences, {1. 4.0074. china 2.institute of {4., china Earthquake Administration, {1. 4.0071. china 3 Earthquake Administration of Xinjiang Uygur Autonomous Region, Urumqi 83001., china 1. Research Center of Space Science and Technology China University of Geosciences Wuhan 430074 China 2. institute of {1. China Earthquake Administration Wuhan 430071 China 3. Earthquake Administration of Xinjiang Uygur Autonomous Region Urumqi 830011 China

Based on GPS measurements conducted from 1.92.to 2.06, we present the current crustal movement velocity field for approximately 4.0 sites in the Tianshan Mountains and their adjacent areas, and estimate slip rates on the major faults using a 2.D elastic dislocation model. Our studies show slip rates within the range of 1.4.mm/a on the NW-SE trending strike-slip faults (such as Talas-Fergana fault) in the Tianshan Mountains. We also found the slip rates on the approximately WE-SN trending gently-dipping detachment fault vary from 1.―1. mm/a for the southwest Tianshan Mountains to 2.5 mm/a for the eastern Tianshan Mountains, and to 6―1. mm/a for the Kyrgrz Tianshan. The GPS velocity field reveals that the total convergence is not uniformly distributed across the Tianshan Mountains, with 80%―90% of the N-S shortening absorbed along the southern and northern edges, and relatively little deformation accommodated within the interior. This first-order feature of strain pattern is explained best by underthrusting of adjacent blocks beneath the Tianshan Mountains along a basal detachment fault. We found the occurrence of historical M7―8 earthquakes somewhere in the locked ramp that connects the creeping and locking segments of the detachment, thereby resulting in elastic strain concentration and accumulation around it. The elastic strain confined in the upper crustal layer above the detachment ultimately releases through infrequent great earthquakes in the Tianshan Mountains, resulting in considerable folding and faulting at their margins. The Tianshan Mountains propagated outward and rose progressively as a wedge-shaped block.

关键词： Tianshan Mountains GPS slip rates tectonic deformation