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Comparative Analysis of Two-component Signal Transduction System in Two Streptomycete Genomes

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Acta Biochimica et Biophysica Sinica 2007年第5期39卷 317-325页

Species of the genus Streptomyces are major bacteria responsible for producing most natural antibiotics. Streptomyces coelicolor A3(2) and Streptomyces avermitilis were sequenced in 2002 and 2003, respectively. Two-component signal transduction systems (TCSs), consisting of a histidine sensor kinase (SK) and a cognate response regulator (RR), form the most common mechanism of transmembrane signal transduction in prokaryotes. TCSs in S. coelicolor A3(2) have been analyzed in detail. Here, we identify and classify the SK and RR of S. avermitilis and compare the TCSs with those of S. coelicolor A3(2) by computational approaches. Phylogenetic analysis of the cognate SK-RR pairs of the two species indicated that the cognate SK-RR pairs fall into four classes according to the distribution of their orthologs in other organisms. In addition to the cognate SK-RR pairs, some potential partners of non-cognate SK-RR were found, including those of unpaired SK and orphan RR and the cross-talk between different components in either strain. Our study provides new clues for further exploration of the molecular regulation mechanism of streptomycetes with industrial importance.

关键词： Streptomyces two-component system cross-talk phylogenetic analysis

Relationship between the Asian-Pacific oscillation and the tropical cyclone frequency in the western North Pacific

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Science China Earth Sciences 2008年第3期51卷 380-385页

作者： ZHOU BoTao1, CUI Xuan2 & ZHAO Ping3 1 laboratory for Climate Studies, National Climate center, China Meteorological Administration, Beijing 100081, China 2 National Meteorological center, China Meteorological Administration, Beijing 100081, China 3 Chinese Academy of Meteorological Sciences, China Meteorological Administration, Beijing 100081, China laboratory for Climate Studies National Climate Center China Meteorological Administration Beijing China National Meteorological center China Meteorological Administration Beijing China Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing China

The relationship between the Asian-Pacific oscillation (APO) and the tropical cyclone frequency over the western North Pacific (WNP) in summer is preliminarily investigated through an analysis of ob- served data. The result has shown clearly that APO is significantly and positively correlated to the tropical cyclone frequency in the WNP. If APO is above (below) the normal in summer, more (less) tropical cyclones will tend to appear in the WNP. The present study also addresses the large-scale at- mospheric general circulation changes underlying the linkage between APO and the WNP tropical cy- clone frequency. It follows that a positive phase of summer APO is concurrent with weakened as well as northward and eastward located western Pacific subtropical high (WPSH), low-level convergence and high-level divergence, and reduced vertical zonal wind shear in the WNP, providing favorable envi- ronment for the tropical cyclone genesis, and thus more tropical cyclones will come into being, and vice versa.

关键词： Asian-Pacific oscillation western North Pacific tropical cyclone atmospheric circulation

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science China(Physics,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3,4, JIANG YunGuo1 & LI XinGuo2,3 1 Institute of Theoretical Physics, College of Applied Sciences, Beijing University of Technology, Beijing 100022, China 2 Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China 3 center of Theoretical Nuclear Physics, National laboratory of Heavy Ion Collisions, Chinese Academy of Sciences, Lanzhou 730000, China 4 China center of Advanced Science and Technology (World laboratory), Beijing 100080, China Institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Beijing China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou China China center of Advanced Science and Technology (World laboratory) Beijing China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

2.5-dimensional angle potential field algorithm for the real-time autonomous navigation of outdoor mobile robots

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Science China(Information Sciences) 2011年第10期54卷 2100-2112页

作者： QIU Quan 1,3 & HAN JianDa 2 1 Beijing Research center of Intelligent Equipment for Agriculture,Beijing 100097,China 2 State Key laboratory of Robotics,Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang 110016,China 3 National Research center for Intelligent Agricultural Equipment,Beijing 100097,China Beijing Research center of Intelligent Equipment for Agriculture Beijing China National Research center for Intelligent Agricultural Equipment Beijing China State Key laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang China

A new real-time algorithm for the autonomous navigation of mobile robots equipped with laser scanners is proposed in this *** from the existing algorithms designed for 2-dimensional navigation problems,the new algorithm introduces the height information of the obstacles into the guidance process and behaves as a 2.5-dimensional angle potential field algorithm (2.5D-APF) to fulfill the navigation requirements under complex outdoor terrain ***,one laser scan is partitioned into two kinds of function sectors: guidance sector and inspecting ***,the guidance sector and the inspecting sectors are reconstructed to form a virtual guidance scan,where the 2.5D information is taken into ***,the conventional APF is improved to analyze the virtual guidance scan and generate the navigation *** new algorithm is tested on a tracked mobile robot,and the experimental results validate the proposed algorithm.

关键词： robot 2.5-dimensional outdoor real-time autonomous navigation

Real-time detection of α1A-AR movement stimulated by phenylephrine in single living cells

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Acta Pharmacologica Sinica 2007年第6期28卷 796-802页

作者： Ning XU~(2,5),Zhang-yi LIANG~(3,5),Ming XU~2,Ying-hua GUAN~3,Qi-hua HE~4,Qi-de HAN~2,Xin-sheng ZHAO~(3,6),You-yi ZHANG~(2,6)~2 Institute of Vascular Medicine,Peking University Third Hospital,and Key laboratory of Molecular Cardiovascular Sciences,Ministry ofEducation,Beijing 100083,China ~3 Beijing National laboratory for Molecular Sciences,State Key laboratory for Structural Chemistry ofUnstable and Stable Species,and Department of Chemical Biology,College of Chemistry and Molecular Engineering,Peking University,Beijing 100871,China ~4 center of Medical Analysis,Peking University,Health Science center,Beijing 100083,China Institute of Vascular Medicine Peking University Third Hospital and Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing China Beijing National laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species Department of Chemical Biology College of Chemistry and Molecular Engineering Peking University Beijing China center of Medical Analysis Peking University Health Science Center Beijing China

Aim:To investigate the movement of α1A-adrenergic receptors(α1A-AR) stimu-lated by agonist,phenylephrine （PE）,and the dynamics of receptor movement inreal time in single living cells with millisecond ***:We labeledα1A-AR using the monoclonal,anti-FLAG （a kind of tag） antibody and Cy3-conju-gated goat anti-mouse IgG and recorded the trajectory of their transport processin living HEK293A cells stimulated by agonist,PE,and then analyzed their dy-namic ***:The specific detection of α1A-AR on the surface ofliving HEK293A-α1Acells was achieved.α1A-AR internalize under the stimulationof *** the cells were stimulated with PE for 20 min,apparent colocalizationwas found between α1A-AR and *** 40 min stimulation of PE,trajecto-ries of approximate linear motion in HEK293A-α1Acells were recorded,and theirvelocity was ***:The specific labeling method on the livingcell surface provides a convenient means of real-time detection of the behavior ofsurface *** this method we were able to specifically detect α1A-AR andrecord the behavior of individual particles of receptors with 50 ms exposure time inreal time in single living cells.

关键词： adrenergic receptor trajectory living cell

Inducible nitric oxide synthase contributes to intermittent hypoxia against ischemia/reperfusion injury

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Acta Pharmacologica Sinica 2005年第3期26卷 315-322页

作者： Hai-lei DING~2 Hai-feng ZHU~2 Jian-wen DONG~2 Wei-zhong ZHU~2 Wei-wei YANG~3 Huang-tian YANG~3 Zhao-nian ZHOU~(2,4)2 Physiological laboratory of Hypoxia,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China 3.laboratory of Molecular Cardiology,Health Science center,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences and Shanghai Second Medical University,Shanghai 200025,China Physiological laboratory of Hypoxia Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China laboratory of Molecular Cardiology Health Science Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences and Shanghai Second Medical University Shanghai China

Aim:To investigate the role of inducible nitric oxide synthase (iNOS)-derivednitric oxide (NO) in the cardioprotection of intermittent hypoxia (IH) against is-chemia/reperfusion (I/R) ***:Langendorff-perfused isolated rathearts were used to measure variables of left ventricular function during baselineperfusion,ischemia,and reperfusion *** plus nitrite (NOx) content inmyocardium was measured using a biochemical method,iNOS mRNA and pro-tein expression in rat left ventricles were detected using reverse transcription poly-merase chain reaction (RT-PCR) and Western blot,***:Myo-cardial function recovered better in IH rat hearts than in normoxic control *** iNOS-selective inhibitor aminoguanidine (AG) (100μmol/L) significantlyinhibited the protective effects of IH,but had no influence on normoxic rat *** baseline content of NOx in IH hearts was higher than that in normoxic *** 30 min ischemia,the NOx level in normoxic hearts increased compared tothe corresponding baseline level,whereas there was no significant change in ***,the NOx level in IH hearts was still higher than that of normoxichearts during ischemia and reperfusion *** 100μmol/L significantly di-minished the NOx content in IH and normoxic hearts during ischemia and *** baseline levels of iNOS mRNA and protein in IH hearts were higherthan those of normoxic *** to the corresponding baseline level,iNOS mRNA and protein levels in normoxic rat hearts increased and those in IH rathearts decreased after *** addition of AG 100μmol/L significantlydecreased iNOS mRNA and protein expression in IH rat hearts after I/***:IH upregulated the baseline level of iNOS mRNA and protein expres-sion leading to an increase in NO production,which may play an important role inthe cardiac protection of IH against I/R injury.

关键词： intermittent hypoxia ischemia/reperfusion inducible nitric oxide synthase aminoguanidine: rats

Upregulation of TNF-αand IL-6 mRNA in mouse liver induced by bacille Calmette-Guerin plus lipopolysaccharide

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Acta Pharmacologica Sinica 2006年第4期27卷 460-468页

作者： Dao-fang LIU~(1,2,3) Wei WEI~(1,4) Li-hua SONG~(1,2,3,4) ~1Institute of Clinical Pharmacology,Key laboratory of Anti-inflammatory and Immunopharmacology in Anhui Province.Key laboratory of Research and Development of Chinese Medicine in Anhui Province.Anhui Medical University,Hefei 230032,China:~2Molecular Biology laboratory,Anhui Biology Institute,Hefei 230088,China ~3center of Research and Development,Anhui Anke Biotechnology Group,Hefei 230088.China Institute of Clinical Pharmacology Key Laboratory of Anti-inflammatory and Immunopharmacology in Anhui Province Key Laboratory of Research and Development of Chinese Medicine in Anhui Province Anhui Medical University Hefei China Molecular Biology laboratory Anhui Biology Institute Hefei China center of Research and Development Anhui Anke Biotechnology Group Hefei China

Aim:To investigate the mechanism of immunological liver injury induced by bacilleCalmette-Guerin(BCG)plus lipopolysaccharide(LPS).Methods:Mice were in-jected via the tail vein with 125 mg/kg BCG,and 12 d later,the mice were injectedintravenously with different doses of LPS(125,250,or 375 μg/kg).Serum alanineaminotransferase(ALT)activity and liver pathological changes were *** expression of tumor necrosis factor(TNF)-α interleukin(IL)-6,lipopolysac-charide binding protein(LBP)and CD14 mRNA,and NF-κB and IκB-α protein inmouse liver at different time points after BCG and LPS injection were measuredusing RT-PCR,immunohistochemistry and Western blotting analysis,***:The activity of serum ALT in mice treated with BCG and LPS was signifi-cantly *** degrees of liver injury,such as inflammatory cellinfiltration,spotty necrosis,piecemeal necrosis,even bridging necrosis,could beseen in liver sections from mice after BCG and LPS ***,thelevels of TNF-α and IL-6 mRNA in mouse liver were significantly elevated afteradministration of BCG plus LPS(P<0.05).The levels of LBP and CD14 mRNA inmouse liver were markedly upregulated after treatment with BCG and LPS,andtreatment with BCG alone led to an increase in CD14 InRNA in mouse ***,immunoreactivity for NF-κB p65 was predominantly detected in hepatocyte nucleifrom mice treated with BCG plus LPS,compared with the normal *** of IκB-α were strikingly decreased by LPS or BCG plus LPS treatment,compared with the normal group or BCG ***:TNF-α and IL-6mRNA were partially involved in early immunological liver injury induced by chal-lenge with small doses of LPS after BCG *** of TNF-α and IL-6 mRNA might be related to increases in LBP and CD 14 mRNA expression andactivation of NF-κ***,BCG priming in immunological liver injury mayoccur via upregulation of CD 14 mRNA expression in monon uclear cell infiltrationinto t

关键词： liver injury lipopolysaccharide binding protein CD14 tumor necrosis factor-alpha interleukin-6 NF-kappa B

New evidence for lack of CMB power on large scales

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： LIU Hao1 & LI TiPei1,2,3 1 Key laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China 2 Department of Physics & center for Astrophysics, Tsinghua University, Beijing 100084, China 3 Department of Engineering Physics & center for Astrophysics, Tsinghua University, Beijing 100084, China Key laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of Physics & center for Astrophysics Tsinghua University Beijing China Department of Engineering Physics & center for Astrophysics Tsinghua University Beijing China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

How random are matrix elements of the nuclear shell model Hamiltonian?

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Science China(Physics,Mechanics & Astronomy) 2009年第10期52卷 1477-1481页

作者： SHEN JiaJie1 & ZHAO YuMing1,2,3,4 1 Department of Physics,Shanghai Jiao Tong University,Shanghai 200240,China 2 center of Theoretical Nuclear Physics,National laboratory of Heavy Ion Accelerator,Lanzhou 730000,China 3 Nishina center,Institute of Physical Chemical Research(RIKEN),Hirosawa 2-1,Wako-shi,Saitama 351-0198,Japan 4 CCAST,World laboratory,Beijing 100080,China Department of Physics Shanghai Jiao Tong University Shanghai China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China Nishina center Institute of Physical Chemical Research (RIKEN) Saitama Japan

In this paper we study the general behavior of matrix elements of the nuclear shell model *** find that nonzero off-diagonal elements exhibit a regular pattern,if one sorts the diagonal matrix elements from smaller to larger *** correlation between eigenvalues and diagonal matrix elements for the shell model Hamiltonian is more remarkable than that for random matrices with the same distribution unless the dimension is small.

关键词： nuclear shell model geometry property linear correlation randomize