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Energy Transfer among Chlorophylls in Trimeric Light-harvesting Complex Ⅱ of Bryopsis corticulans

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 310-317页

作者： Su-Juan ZHANG~(1,2*)Shui-Cai WANG~2 Jun-Fang HE~2 Hui CHEN~3. 1 institute of Photonics and Photo-Technology,Northwest University,Xi'an 710069,china 2 State key {3. of Transient Optics and Photonics,Xi 'an institute of Optics and Precision Mechanics,chinese academy of sciences,Xi'an 710068.china 3.Laboratoty of Photosynthesis Basic Research,institute of Botany,chinese academy of sciences,Beijing 100093.china institute of Photonics and Photo-Technology Northwest UniversityXi'an 710069 China State key laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi'an 710068 China laboratory of Photosynthesis Basic Research Institute of Botany Chinese Academy of SciencesBeijing 100093 China

A study on energy transfer among chlorophylls（Chls）in the trimeric unit of the major light-harvesting complex Ⅱ（LHC Ⅱ）from Bryopsis corriculan,was carried out using time-correlated singlephoton *** the chlorophyll Q region of LHC Ⅱ,six molecules characterized as Chlb628,Chlb646,Chlb652654,657,Chla664666,Chla674677.680and Chla682683.ere discriminated according to their absorption spectrumand fluorescence emission ***,excited by pulsed light of 628 nm,fluorescence kinetics spectrain the chlorophyll Q region were *** accordance with the principles of fluorescence kinetics,thesekinetics data were analyzed with a multi-exponential *** constants on energy transfer were *** overwhelming percentage of energy transfer among chlorophylls undergoes a process longer than 97picoseconds（ps）,which shows that,before transferring energy to another Chl,the excited Chl might convertenergy to vibrations of a lower state with different multiplicity（intersystem crossing）.Energy transfer at thelevel of approximately 10 ps was also obtained,which was interpreted as the excited Chls may go throughinternal conversion before transferring energy to another *** with a higher standard deviation,timeconstants at the femtosecond level can not be entirely excluded,which can be attributed to the ultrafastprocess of direct energy *** to the arrangement and direction of the dipole moment of Chls inLHC Ⅱ,the probability of these processes is *** fluorescence lifetimes of Chlb652654,657,Chla664666,Chla674677.680and Chla682683.ere determined to be 1.44ns,1.43.ns,63. ps and 713.ps,*** of energy dissipation in the pathway of fluorescence emission were no more than 40% in thetrimeric unit of LHC Ⅱ.These results are important for a better understanding of the relationship between thestructure and function of LHC Ⅱ.

关键词： energy transfer LHC Ⅱ transient spectrum fluorescence kinetics

Transiently Expressed Short Hairpin RNA Targeting 126 kDa Protein of Tobacco Mosaic Virus Interferes with Virus Infection

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 22-28页

作者： Ming-Min ZHAO~(1,2),De-Rong AN~(1*),Jian ZHAO~2,Guang-Hua HUANG~3.Zu-Hua HE~4,and Jiang-Ye CHEN~3. ~1 College of Plant Protection,Northwest Science and Technology University of Agriculture and Forestry,Yangling 712100,china ~2 College of Agriculture,Yangtze University,Jingzhou 43.025,china ~3.State key {3. of Molecular Biology,{3. of Biochemistry and Cell Biology,Shanghai {3.s for Biological sciences, chinese academy of sciences,Shanghai 20003.,china ~4 State key {3. of Plant Molecular Genetics,{3. of Plant Physiology and Ecology,Shanghai {3.s for Biological sciences, chinese academy of sciences,Shanghai 20003.,china College of Plant Protection Northwest Science and Technology University of Agriculture and Forestry Yang ling 712100 China College of Agriculture Yangtze University Jingzhou 434025 China State key laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China State key laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

RNA-interference (RNAi) silences gene expression by'guiding mRNA degradation in asequence-specific *** interfering RNA (siRNA),an intermediate of the RNAi pathway,has beenshown to be very effective in inhibiting virus infection in mammalian cells and cultured plant ***,wereport that Agrobacterium tumefaciens-mediated transient expression of short hairpin RNA (shRNA) couldinhibit tobacco mosaic virus (TMV) RNA accumulation by targeting the gene encoding the replication-asso-ciated 126 kDa protein in intact plant *** results indicate that transiently expressed shRNA efficientlyinterfered with TMV *** interference observed is sequence-specific,and time-and *** expressed shRNA corresponding to the TMV 126 kDa protein gene did not inhibit cucumbermosaic virus (CMV),an unrelated *** order to interfere with TMV accumulation in tobaccoleaves,it is essential for the shRNA constructs to be infiltrated into the same leaves as TMV *** support the view that RNAi opens the door for novel therapeutic procedures against virus *** propose that a combination of the RNAi technique and Agrobacterium-mediated transient expressioncould be employed as a potent antiviral treatment in plants.

关键词： tobacco mosaic virus 126 kDa protein RNA interference short hairpin RNA

Plastic deformation of nanocrystalline nickel

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Science china(Technological sciences) 2009年第8期52卷 2216-2221页

作者： WU XiaoLei State key laboratory of Nonlinear Mechanics, institute of Mechanics,{3., Beijing 100190,{3. State key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

A high-resolution electron microscopy study has uncovered the plastic behavior of accommodating large strains in nanocrystalline (NC) Ni subject to cold rolling at liquid nitrogen temperature. The activation of grain-boundary-mediated-plasticity is evidenced in NC-Ni, including twinning and formation of stacking fault via partial dislocation slips from the grain boundary. The formation and storage of 60? full dislocations are observed inside NC-grains. The grain/twin boundaries act as the barriers of dislocation slips, leading to dislocation pile-up, severe lattice distortion, and formation of sub-grain boundary. The vicinity of grain/twin boundary is where defects preferentially accumulate and likely the favorable place for onset of plastic deformation. The present results indicate the heterogeneous and multiple natures of accommodating plastic strains in NC-grains.

关键词： nanocrystalline metal plastic deformation deformation twinning dislocation microstructure

DMTB:A comprehensive online resource of 16S rRNA genes,ecological metadata,oligonucleotides,and magnetic properties of magnetotactic bacteria

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chinese Science Bulletin 2011年第6期56卷 476-478页

作者： LIN Wei1,2, LI Bi1,2 & PAN YongXin1,2 1 Paleomagnetism and Geochronology laboratory, key laboratory of the Earth’s Deep Interior, {3. of Geology and {3., chinese academy of sciences, Beijing 100029, china 2 France-china Bio-Mineralization and Nano-Structures laboratory, {3. of Geology and {3., chinese academy of sciences, Beijing 100029, china Paleomagnetism and Geochronology laboratory Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China France-china Bio-Mineralization and Nano-Structures laboratory Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Magnetotactic bacteria (MTB) are of interest in microbiology, biomineralization, advanced magnetic materials, and bio-geo-sciences because of their ability to form highly ordered intracellular magnetic minerals. Great strides for MTB studies have been made in the past four decades. In this paper we complied the first internet-accessible database for MTB, Database of Magnestotactic Bacteria (DMTB). It contains information of 16S rRNA gene sequences, corresponding ecological metadata, oligonucleotides, and magnetic properties of MTB. The comprehensive information contained in DMTB will provide a very useful data resource for researchers from different disciplines. The website of DMTB is at http://***/.

关键词： rRNA基因序列趋磁细菌 16S 网上资源寡核苷酸磁学性质生态磁性材料

The effects of K^+ growth conditions on the accumulation of cesium by the bacterium Thermus sp. TibetanG6

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Science china(Life sciences) 2006年第2期49卷 123-129页

作者： WANG Hailei1,2,3. KONG Fanjing1,2,3.& ZHENG Mianping1,2,3.1. R&D Center for Saline Lake and Epithermal Deposits, chinese academy of Geological sciences, Beijing 10003.,{3. 2. key Open laboratory of Saline Lake Resources and Environment, chinese academy of Geological sciences, Beijing 10003.,{3. 3. institute of Mineral Resources, chinese academy of Geological sciences, Beijing 10003.,{3. R&D Center for Saline Lake and Epithermal Deposits Chinese Academy of Geological Sciences Beijing China key Open laboratory of Saline Lake Resources and Environment Chinese Academy of Geological Sciences Beijing China institute of Mineral Resources Chinese Academy of Geological Sciences Beijing China

The accumulation of cesium by the bacterium Thermus sp. TibetanG6 was examined under different K+ growth conditions. The effects of external pH and Na+ on the accumulation of ce-sium were also studied, and the mechanism involved was discussed. K+ regimes played an important role in the accumulation of cesium by the strain TibetanG6. The quantity of cesium accumulated (24 h) was much higher in K+-deficient regime than that in K+-sufficient regime. The pH and Na+ had different effects on the accumulation of cesium in the two K+ regimes. IR spectra analyses indicated that the biosorption is a process of homeostasis with cesium initially accumulated on the cell wall.

关键词： Thermus sp. TibetanG6, cesium, bioaccumulation, K+-growth condition, pH, sodium, IR spectroscopy.

Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

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Science china Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3. MA Haizhou2, LI Zhen4, TAN Hongbing2 & WANG Xianyan1 1. State key laboratory of Loess and Quaternary Geology, institute of Earth Environment,{3., Xi’an 710075{3. 2. Qinghai institute of Salt Lakes,{3.. Xining 810008,{3. 3. institute of Geology and geophysics,{3., Beijing 100029,{3. 4. Department of Geography, Qinghai Normal University, Xining 810008,{3. State key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China institute of Geology and geophysics Chinese Academy of Sciences Beijing China Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining China Department of Geography Qinghai Normal University Xining China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (103. samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3. T2, T1 were formed at 14, 11.3. 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3. 1.2 and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 43. m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3.1. National Marine Environmental Forecasting Center, Beijing 100081, china 2. key laboratory Regional Climate-Environment for Temperate East Asia, {3. of Atmospheric Physics,{3., Beijing 100029, china 3. Graduate University of{3., Beijing 100049, china National Marine Environmental Forecasting Center Beijing China key laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

A puzzle of the radio-quiet quasar PG 1407+265:Are optical and X-ray emissions produced from a relativistic jet?

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2,3.& BAI JinMing 1,2 1 National Astronomical Observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,{3. 2 key laboratory for the Structure and Evolution of Celestial Objects,chinese academy of sciences,Kunming 650011,{3. 3.Graduate University of chinese academy of sciences,Beijing 100049,{3. National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming China key laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming China Graduate University of chinese academy of sciences Beijing China

PG 1407+265 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+265,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+265

Magnesium lithospermate B ameliorates renal cortical microperfusion in rats

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Acta Pharmacologica Sinica 2006年第2期27卷 217-222页

作者： Chun-guang CHEN~(2,3. Yi-ping WANG~(2,4) ~2State key laboratory of Drug Research.Shanghai institute of Materia Medica,Shanghai institutes for Biological {3. Graduate School of the chinese academy of sciences,chinese academy of {3.,Shanghai 201203.china State key laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Shanghai China Graduate School of the chinese academy of sciences Chinese Academy of Sciences Shanghai China

Aim:To investigate the effects of magnesium lithospermate B（MLB）isolatedfrom Salviae miltiorrhizae on renal microcirculation,and renal and systemic he-modynamics in Sprague-Dawley ***:MLB（10,3.,and 60 mg/kg）wasinjected intravenously and renal blood flow（RBF）,renal cortical microperfusion（RCM）,and systemic hemodynamic function parameters including heart rate（HR）,mean arterial pressure（MAP）,left ventricular systolic pressure（LVSP）,left ven-tricular end-diastolic pressure（LVEDP）,and maximal velocity of pressure increase(dp/dtmax)were measured for 45 min after ***:IntravenousMLB at doses of 10,3.,and 60 mg/kg increased RCM significantly,but had noobvious effects on RBF or systemic *** effect of MLB on RCMreached its peak 15 rain after injection and returned to baseline after 45 *** to60 mg/kg MLB increased RCM by 62.4%±20.2%（changes from baseline,P3.7%±9.7% vs baseline）and renal vascular resistance（-1.4%±9.1%vs baseline）did not obviously ***:These results indicate thatMLB ameliorates renal microcirculation in a dose-dependent manner,which maybe related to the renoprotective effects of MLB.

关键词： magnesium lithospermate B hemodynamics renal blood flow renal cortical microperfusion