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Theoretical study of interactions between human adult hemoglobin and acetate ion by polarizable force field and fragmentation quantum chemistry methods

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Science China Chemistry 2009年第11期52卷 1925-1931页

作者： YAN XiuFen JIANG Nan ma jing School of Chemistry and Chemical Engineering Institute of Theoretical and Computational ChemistryKey Laboratory of Mesoscopic Chemistry of MOENanjing UniversityNanjing 210093China

A series of theoretical approaches,including conventional FF03 and FF03-based polarization model,as well as the generalized energy-based fragmentation(GEBF) quantum chemistry method,have been applied to investigate the interactions between acetate ion(CH3COO-) and the α-subunit of human adult hemoglobin(designated as Hb-α) at four binding sites(Lys16,Lys90,Arg92,and Lys127),*** FF03-based polarizable force fields show that the interaction energies between the CH3COO-group and Hb-α follow the trend of Arg92>Lys127>Lys90>*** complexation of CH3COO-with Hb-α is governed by the long-range electrostatic interactions and steric effect.

关键词： polarization model fragmentation QM method hemoglobin interaction

Square-Free Integers as Ideal Norms

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Acta mathematica Sinica,English Series 2010年第4期26卷 621-628页

作者： Shigeru KANEMITSU Antanas LAURINCIKAS jing ma Graduate School of Advanced Technology Kinki University Iizuka Fukuoka 820-8555 Japan Department of mathematics and Informatics Vilnius University Naugarduko 24 LT 03225 Vilnius Lithuania Department of mathematics Jilin University Changchun 130012 P. R. China School of mathematics and System Sciences Shandong University Jinan 250100 P. R. China

Elaborating on Katzel＇s result, Zhai obtained a sharp short interval result for the number of ways of expressing a square-free integer as sums of two squares. In this note we view Zhai＇s decom- position as one by de... 详细信息

关键词： square-free integer ideal norm quadratic field

Field Effects on the Statistical Behavior of the Molecular Conductance in a Single Molecular Junction in Aqueous Solution

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Nano Research 2010年第5期3卷 350-355页

作者： Hui Cao jing ma Yi Luo Department of Theoretical Chemistry School of BiotechnologyRoyal Institute of TechnologyS-10691 StockholmSweden School of Chemistry and Chemical Engineering Institute of Theoretical and Computational ChemistryKey Laboratory of Mesoscopic Chemistry of Ministry of EducationNanjing UniversityNanjing 210093China

We have combined molecular dynamics simulations with first-principles calculations to study electron transport in a single molecular junction of perylene tetracarboxylic diimide (PTCDI) in aqueous solution under external electric gate fields. It is found that the statistics of the molecular conductance are very sensitive to the strength of the electric field. The statistics of the molecular conductance are strongly associated with the thermal fluctuation of the water molecules around the PTCDI molecule. Our simulations reproduce the experimentally observed three orders of magnitude enhancement of the conductance, as well as the temperature dependent conductance, under the electrochemical gates. The effects of the molecular polarization and the dipole rearrangement of the aqueous solution are also discussed.

关键词： Molecular junction field effect solvent effect temperature effect statistical behavior

Multiplication formulas for Kubert functions

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Frontiers of mathematics in China 2014年第1期9卷 101-109页

作者： Hailong LI jing ma Yuichi URAmaTSU Department of mathematics Weinan Teachers' University Weinan 714000 China School of mathematics Jilin University Changchun 130012 China Graduate School of Advanced Technology Kinki University Iizuka Fukuoka 820-8555 Japan

The aim of this paper is two folds. First, we shall prove a general reduction theorem to the Spannenintegral of products of （generalized） Kubert functions. Second, we apply the special case of Carlitz＇s theorem to the elaboration of earlier results on the mean values of the product of Dirichlet L-functions at integer arguments. Carlitz＇s theorem is a generalization of a classical result of Nielsen in 1923. Regarding the reduction theorem, we shall unify both the results of Carlitz （for sums） and Mordell （for integrals）, both of which are generalizations of preceding results by Frasnel, Landau, Mikolas, and Romanoff et al. These not only generalize earlier results but also cover some recent results. For example, Beck＇s lamma is the same as Carlitz＇s result, while some results of maier may be deduced from those of Romanoff. To this end, we shall consider the Stiletjes integral which incorporates both sums and integrals. Now, we have an expansion of the sum of products of Bernoulli polynomials that we may apply it to elaborate on the results of afore-mentioned papers and can supplement them by related results.

关键词： Kubert function multiplication formula integral formula Bernoulli polynomial mean value

Mutation of Residue Arginine^18 of Cytochrome b559 α-Subunit and its Effects on Photosystem Ⅱ Activities in Chlamydomonas reinhardtii

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Journal of Integrative Plant Biology 2007年第7期49卷 1054-1061页

作者： jing-jing ma Liang-Bi Li Yu-Xiang jing Ting-Yun Kuang Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

It has been known that arginine is used as the basic amino acid in the α-subunit of cytochrome bsss （Cyt bsss） except histidine. However, previous studies have focused on the function of histidine in the activities of photosystem （PS） Ⅱ and there are no reports regarding the structural and/or functional roles of arginine in PSll complexes. In the present study, two arginine18 （R18） mutants of Chlamydomonas reinhardtii were constructed using site-directed mutagenesis, in which R18 was replaced by glutamic acid （E） and glycine （G）. The results show that the oxygen evolution of the PSII complex in the R18G and R18E mutants was approximately 60% of wild-type （WT） levels and that, after irradiation at high light intensity, oxygen evolution for the PSll of mutants was reduced to zero compared with 40% in WT cells. The efficiency of light capture by PSll （Fv/Fm） of R18G and R18E mutants was approximately 42%-46% that of WT cells. Furthermore, levels of the α-subunit of Cyt bsss and PsbO proteins were reduced in thylakoid membranes compared with WT. Overall, these data suggest that R18 plays a significant role in helping Cyt bss9 maintain the structure of the PSll complex and its activity, although it is not directly bound to the heme group.

关键词： Chlamydomonas reinhardtii chloroplast transformation cytochrome b559 mutation photosystem Ⅱ.

DBS imaging based on Keystone transform

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Journal of Systems Engineering and Electronics 2012年第3期23卷 342-348页

作者： jing Tian Wei Cui Lin ma Siliang Wu Radar Research Institute Beijing Institute of TechnologyBeijing 100081E R.China

To correct the range walk through resolution cell in Doppler beam sharpening （DBS） imaging, a new DBS imaging algorithm based on Keystone transform is proposed. Without the exact values of the movement parameters and the look angle of the radar platform in the multi-targets environment, a linear trans- form on the received data is employed to correct different range walk values accurately under the condition of Doppler frequency ambiguity in this algorithm. This method can realize the cohe- rent integration in azimuth dimension and improve the azimuth resolution. In order to reduce the computational burden, a fast implementation of Keystone transform is used. Theoretical anal- ysis and simulation results demonstrate the effectiveness of the new algorithm. And through comparing the computational load of the fast implementation with several other algorithms, the real-time processing ability of the proposed algorithm is superior to that of other algorithms.

关键词： Doppler beam sharpening (DBS) Keystone transform range walk coherent integration.

Modeling Method and Application of Rational Finite Element Based on Absolute Nodal Coordinate Formulation

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Acta Mechanica Solida Sinica 2018年第2期31卷 207-228页

作者： Chao ma Cheng Wei jing Sun Bin Liu Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing Institute of Spacecraft System Engineering Department of Aerospace Engineering Harbin Institute of Technology

In multibody system dynamics, the absolute nodal coordinate formulation （ANCF） uses power functions as interpolating polynomials to describe the displacement field. It can get accurate results for flexible bodies that undergo large deformation and large rotation. However, the power functions are irrational representation which cannot describe the complex shapes precisely, especially for circular and conic sections. Different from the ANCF representation, the rational absolute nodal coordinate formulation （RANCF） utilizes rational basis functions to describe geometric shapes, which allows the accurate representation of complicated displacement and deformation in dynamics modeling. In this paper, the relationships between the rational surface and volume and the RANCF finite element are provided, and the generalized transformation matrices are established correspondingly. Using these transformation matrices, a new four-node three-dimensional RANCF plate element and a new eight-node three-dimensional RANCF solid element are proposed based on the RANCF. Numerical examples are given to demonstrate the applicability of the proposed elements. It is shown that the proposed elements can depict the geometric characteristics and structure configurations precisely, and lead to better convergence in comparison with the ANCF finite elements for the dynamic analysis of flexible bodies.

关键词： Multibody system dynamics Absolute nodal coordinate formulation Flexible deformation Spline representation Rational finite element

Nonlinear dynamics and station-keeping control of a rotating tethered satellite system in halo orbits

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Chinese Journal of Aeronautics 2013年第5期26卷 1227-1237页

作者： Liu Gang Huang jing ma Guangfu Li Chuanjiang Department of Control Science and Engineering Harbin Institute of Technology

The dynamics of a rotating tethered satellite system （TSS） in the vicinity of libration points are highly nonlinear and inherently unstable. In order to fulfill the station-keep control of the rotating TSS along halo orbits, a nonlinear output tracking control scheme based on the θ- D technique is proposed. Compared with the popular time-variant linear quadratic regulator （LQR） controller, this approach overcomes some limitations such as on-line computations of the algebraic Riccati equation. Besides, the obtained nonlinear suboptimal controller is in a closed form and easy to implement. Numerical simulations show that the TTS trajectories track the periodic reference orbit with low energy consumption in the presence of both tether and initial injection errors. The axis of rotation can keep pointing to an inertial specific object to fulfill an observation mission. In addition, the thrusts required by the controller are in an acceptable range and can be implemented through some low-thrust propulsion devices.

关键词： Halo orbit Restricted three-body problem Station-keeping control Suboptimal control Tethered satellite system

A dynamic influence model of social network hotspot based on grey system

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Science China(Information Sciences) 2015年第12期58卷 63-74页

作者： XIAO YunPeng ma jing LIU YanBing YAN ZhiXian Chongqing University of Posts and Telecommunications (CQUPT) Swiss Federal Institute of Technology (EPFL)

The outbreak of hotspot in social network may contain complex dynamic genesis. Using user behavior data from hotspots in social network, we study how different user groups play different roles for a hotspot topic. Firstly, by analyzing users’ behavior records, we mine group situation that promotes the *** major attributions in a hotspot outbreak, such as individual, peer and group triggers, are defined formally according to the view-point of social identity, social interaction, retweet depth and opinion leader. Secondly,for the problem of the uneven and sparse data in each stage of hotspot topic’s life cycle, we propose a dynamic influence model based on grey system to formalize the effect of different groups. Then the process of hotspot evolution driven by distinct crowd is showed dynamically. The experimental result confirms that the model is able not only to qualify users’ influence on a hotspot topic but also to predict effectively an upcoming change in a hotspot topic.

关键词： social network hotspot topic grey system influence model dynamic evolution