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Nonculturability of the pathogenic Vibrio parahaemolyticus in live culture of Grateloupia turuturu is associated with bacterial attachment to the algal thalli

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Acta Oceanologica Sinica 2010年第6期29卷 92-103页

作者： LIU Feng PANG Shaojun Marine Biological Culture Collection Centre Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate university of{2. academy of sciences Beijing 100049 China

The invasive red alga Grateloupia turuturu Yamada could turn Vibrio parahaemolyticus into nonculturable state in live algal *** order to elucidate the mechanism of such an effect,a series of culture experiments were performed in this investigation based on three hypothesized causes,namely bacterial attachment,production of reactive oxygen species （ROS） and the discharge of water soluble secondary metabolic *** results reveal that attachment to the thallus surface of *** was the major reason for the decrease of *** in *** investigations show that *** attachment to the surface of algal thallus in live cultures of seaweeds was a common ***,the disappearance of the culturability of *** occurred only on the thallus of *** over 72.h among all six algal species *** microscopic scanning shows that most of *** attached to *** changed from the initial normal bacilli to coccoid-shape after 72.*** enclosure experiments by enclosing the algal thallus in tubes demonstrate that the nonculturability of *** in the water of live culture of *** occurred after the physical contact of the *** to the *** capacity of *** in affecting the culturability of *** was not influenced after inhibition of photosynthesis by treatment of 3（3,4dichlorophenyl）-1 ,1dimethyl urea （DCMU） at non-lethal *** of reactive oxygen species after addition of live culture of bacteria was excluded by on-line analyzing the oxidation of dichlorohydrofluorescein （DCFH） to dichlorofluorescein （DCF） in the presence of peroxidase on a VersaFluor fluorometer.

关键词： Grateloupia turuturu attachment Vibrio parahaemolyticus nonculturability effective quantum yield

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science China Earth sciences 2010年第5期53卷 763-772页

作者： CHEN BaiLian1,3, ZHANG RenHe2. SUN ShuFen1, BIAN LinGen2. XIAO CunDe4,2.& ZHANG TingJun5 1 Institute of Atmospheric Physics, chinese academy of{2., beijing 10002., China 2.chinese academy of Meteorological{2., beijing 100081, China 3 graduate university of chinese academy of{2., beijing 100049, China 4 Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of{2., Lanzhou 730000, China 5 The National Snow and Ice Data Center, university of Colorado, Boulder, CO 80309-0449, USA 1. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Chinese Academy of Meteorological Sciences Beijing 100081 China4. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China5. The National Snow and Ice Data Center University of Colorado Boulder CO 80309-0449 USA

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°2.′S, 70°2.′E), we applied the model to simulate the seasonal temperature variation within a depth of 2. m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3, 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2. the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

A SAR sidelobe suppression algorithm based on modified spatially variant apodization

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Science China(Technological sciences) 2010年第9期53卷 2542-2551页

作者： NI Chong1,2.WANG YanFei1,XU XiangHui1,ZHOU ChangYi1 & CUI PengFei1,2.1 Institute of Electronics,chinese academy of{2.,beijing 100190,China 2.graduate university of chinese academy of{2.,beijing 100039,China 1. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100039 China

The existing spatially variant apodizations (SVAs) either cannot depress the sidelobes effectively or reduce the energy of the *** improve this,a modified SVA (MSVA) is put forward in this paper,which expands the traditional filter from 3-taps to 5-taps and sets relevant parameters according to different sampling rates to get the excellent result that satisfies constrained optimization theory.A method for synthetic aperture radar (SAR) sidelobe control based on MSVA is presented,which applies MSVA to range compression and azimuth compression to control *** method which is available for any Nyquist sampling rate can both depress the sidelobes effectively and keep the energy of the mainlobe and the resolution of the *** method can reduce sidelobe levels more effectively than classical amplitude weighting while maintaining the image resolution,as demonstrated by the result of the experiment.

关键词： synthetic aperture radar sidelobe suppression resolution SVA

A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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Science China(Technological sciences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2.& FENG Xueshang1,3 1. SIGMA Weather Group, Key Laboratory of Space Weather, Center for Space Science and Applied Re-search, chinese academy of{2., beijing 100080, China 2. graduate School of the chinese academy of{2., beijing 100039, China 3. School of Geophysics and Geoinformation Systems, China university of Geosciences, beijing 100083, China 1. SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. graduate School of the chinese{2. of sciences 100039 Beijing China 3. School of Geophysics and Geoinformation Systems China University of Geosciences 100083 Beijing China

Using 80 CME-ICME events during 1997.1―2.02.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2. The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3) The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 30% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

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 2.31. School of Information Engineering, Zhejiang Forestry College, Hangzhou 311300, Zhejiang, China 2. Institute of Computing Technology, chinese academy of{2., beijing 100080, China 3. graduate School of the chinese academy of{2., 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

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{2.,Kunming 650011,China 2.graduate university of the chinese academy of{2.,beijing 100049,China chinese Acad Sci Yunnan Observ Natl Astron Observ Kunming 650011 Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R 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

The correspondence between the concepts in description logics for contexts and formal concept analysis

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Science China(Information sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1,2.SUI YueFei 1 & CAO CunGen 1 1 Key Laboratory of Intelligent Information Processing,Institute of Computing Technology,chinese academy of{2.,beijing 100190,China 2.graduate university of chinese academy of{2.,beijing,China 1. Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role

Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

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Science China Earth sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3 1. Key Laboratory of Lake Sedimentation and Environment, Nanjing Institute of Geography and Limnology, chinese academy of{2., Nanjing 2.0008, China 2. Institute of Tibetan Plateau Research, chinese academy of{2., beijing 10085, China 3. graduate university of chinese academy of{2., beijing 100039, China 1. Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 10085 China 3. graduate university of{2. academy of sciences Beijing 100039 China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 2.0Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14C age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 2.0Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14C dating is stronger. Based on the analysis on results of 14C, 2.0Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C calendar ages, and establish the time sequence for cores CE-1 and CE-2.with result of 2.0Pb CRS model for the upper 35 cm and re-calculated 14C calendar age for sediments bellow 35 cm. Since 1400 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14C, 2.0Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.

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{2.,Changchun 13002.,China 2.graduate university of chinese academy of{2.,beijing 100049,China 1. Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 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 2. *** 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