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FINITE ELEMENT APPROXIMATIONS OF SyMMETRIC TENSORS ON SIMPLICIAL GRIDS IN R^n： ThE hIGhER ORDER CASE

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Journal of Computational Mathematics 2015年第3期33卷 283-296页

作者： Jun hu LMAM School of Mathematical Sciences and Beijing International Center for Mathematical Research Peking University Beijing 100871 P. R. China.

The design of mixed finite element methods in linear elasticity with symmetric stress approximations has been a longstanding open problem until Arnold and Winther designed the first family of mixed finite elements where the discrete stress space is the space of h（div,Ω;S）-Pk＋1 tensors whose divergence is a Pk-1 polynomial on each triangle for k ≥ 2. Such a two dimensional family was extended, by Arnold, Awanou and Winther, to a three dimensional family of mixed elements where the discrete stress space is the space of h（div, Ω; S）-Pk＋2 tensors, whose divergence is a Pk-1 polynomial on each tetrahedron for k ≥ 2. In this paper, we are able to construct, in a unified fashion, mixed finite element methods with symmetric stress approximations on an arbitrary simplex in R^n for any space dimension. On the contrary, the discrete stress space here is the space of h（div,Ω; S）-Pk tensors, and the discrete displacement space here is the space of L^2（Ω; R^n）-Pk＋1 vectors for k ≥ n＋ 1. These finite element spaces are defined with respect to an arbitrary simplicial triangulation of the domain, and can be regarded as extensions to any dimension of those in two and three dimensions by.h. and Zhang.

关键词： Mixed finite element Symmetric finite element First order system Simplicial grid Inf-sup condition.

Mutations in hemagglutinin of a Novel Avian-Origin h7N9 Virus That Are Critical for Receptor Binding Specificity

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Tsinghua Science and Technology 2013年第5期18卷 522-529页

作者： Wei hu the Department of Computer Science Houghton College

A novel avian-origin h7N9 influenza virus was discovered in March in China and has caused a total of131 people infected including 39 deaths in China as of June 9, 2013. Adaptation of avian viruses to efficiently infect humans requires the viral hemagglutinin（hA） binding switches from avian to human type receptors with help of some mutations in hA. As such it is critical for pandemic assessment to discover these mutations as hallmarks of adaptation. To continue our previous study of this novel h7N9 virus, we identified two sets of mutations in hA. The first set of mutations are present in the current circulating strains of 2013 h7N9 in China, and the second set are potential mutations that were found when compared to the hAs of previous human h7 subtype. These two sets of mutations exhibited unique features. The first group of mutations, on average, enhanced the hA binding to human type receptors whereas reduced that to avian types. Further the reduction of avian binding was almost three times of the increase of the human binding. The second group increased the binding to both human and avian *** the increase in human types was almost three times of that in the avian types. Though different in their way of changing the binding preference, these two sets of mutations both contained more mutations to decrease the avian binding and increase the human binding than those that did the opposite. Our research highlighted the pandemic potential of this novel virus by showing the important mutations that could potentially.h.lp it to adapt to human hosts. Our findings offered new insights into the current state of evolution of this virus, which might be helpful for the continued surveillance of the emergence of h7N9 strains having the ability of human-to-human transmission.

关键词： h7N9 influenza receptor binding specificity mutation hA gene

Wild-type and molten globular chorismate mutase achieve comparable catalytic rates using very different enthalpy/entropy compensations

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Science China Chemistry 2014年第1期57卷 156-164页

作者： hu hao Department of Chemistry The University of Hong Kong

The origin of the catalytic power of enzymes with a meta-stable native state,*** globular state,is an unsolved challenging issue in *** help understand the possible differences between this special class of enzymes and the typical ones,we report here computer simulations of the catalysis of both the well-folded wild-type and the molten globular mutant of chorismate *** the ab initio quantum mechanical/molecular mechanical minimum free-energy path method,we determined the height of reaction barriers that are in good agreement with experimental ***-substrate interactions were analyzed in detail to identify factors contributing to *** angular order parameters of backbone N–h bonds and side-chain methyl groups suggested site-specific,non-uniform rigidity changes of the enzymes during *** change of conformational entropy from the ground state to the transition state revealed distinctly contrasting entropy/enthalpy compensations in the dimeric wild-type enzyme and its molten globular monomeric variant.A unique catalytic strategy was suggested for enzymes that are natively molten globules:some may possess large conformational flexibility to provide strong electrostatic interactions to stabilize the transition state of the substrate and compensate for the entropy loss in the transition *** equilibrium conformational dynamics in the reactant state were analyzed to quantify their contributions to the structural transitions enzymes needed to reach the transition *** results suggest that large-scale conformational dynamics make important catalytic contributions to sampling conformational regions in favor of binding the transition state of substrate.

关键词： conformational entropy,enthalpy entropy compensation,enzyme evolution

The emerging applications of pillararene architectures in supramolecular catalysis

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Chinese Chemical Letters 2022年第1期33卷 89-96页

作者： Kaiya Wang Xueqi Tian Jacobs h.Jordan Krishnasamy Velmurugan Leyong Wang Xiao-yu hu College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China The Southern Regional Research Center Agricultural Research ServiceUSDANew OrleansLA 70124United States Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Over the last decade,numerous research efforts have been devoted to pillar[n]arenes since their *** popularity of pillararenes is a reflection of current research trend in supramolecular and macrocyclic chemistry in *** the vast applications(such as chemosensors,drug delivery,transmembrance channels,and separation)of pillararenes,their utilization in catalysis is a relatively less explored ***,soaring attention has been paid by researchers in recent years and this field has seen gradual increasing ***,in this review we will discuss progress in the emerging applications of pillararene architectures in catalysis based on various reaction genre including reduction,oxidation,coupling,decomposition and ***,this review not only focuses on the pillararenes based current progress in catalysis,but also provides the signs for future development in this research field.

关键词： Supramolecular catalysis host–guest chemistry Macrocycles Pillararene Self-assembly

Co_(4)^(Ⅱ)O_(4)立方烷簇的合成、结构、质谱学和电催化性质研究

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湖北大学学报（自然科学版） 2025年第1期47卷 146-152页

作者：张越胡泉源湖北大学化学化工学院湖北武汉430062

以2-甲基-2-(1 h-苯并咪唑基)-1,3丙二醇配体与3d过渡金属Co离子通过溶剂热法配位合成配合物,借助X-射线单晶衍射仪进行晶体结构检测。结果表明:中心离子C_(O)(Ⅱ)以六配位形成八面体构型,该晶体属于单斜晶系,其中a(nm)=1.25579(3),b(nm... 详细信息

以2-甲基-2-(1 h-苯并咪唑基)-1,3丙二醇配体与3d过渡金属Co离子通过溶剂热法配位合成配合物,借助X-射线单晶衍射仪进行晶体结构检测。结果表明:中心离子C_(O)(Ⅱ)以六配位形成八面体构型,该晶体属于单斜晶系,其中a(nm)=1.25579(3),b(nm)=1.88920(8),c(nm)=2.39851(5),α(°)=90,β(°)=95.379(2),γ(°)=90(2),ESI-MS、XRD、TG-MS等常规测试手段研究了此配合物的基本结构、固液性质和物化性能,同时电催化氧化表征测试结果表明在电流密度为10 mA^(-2)时,其催化过电位为344 mV。

关键词：配合物晶体结构质谱电催化

Dynamic Evasion-Interrogation Games with Uncertainty in the Context of Electromagetics

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Numerical Mathematics(Theory,Methods and Applications) 2011年第3期4卷 359-378页

作者： h.T.Banks Shuhua hu K.Ito Sarah Grove Muccio Center for Research in Scientific Computation North Carolina State UniversityRaleighNC 27695-8212USA.

We consider two player electromagnetic evasion-pursuit games where each player must incorporate significant uncertainty into their design strategies to disguise their intension and confuse their *** this paper,the evader is allowed to make dynamic changes to his strategies in response to the dynamic input with uncertainty from the *** problem is formulated in two different ways;one is based on the evolution of the probability density function of the intensity of reflected signal and leads to a controlled forward Kolmogorov or Fokker-Planck *** other formulation is based on the evolution of expected value of the intensity of reflected signal and leads to controlled backward Kolmogorov *** addition,a number of numerical results are presented to illustrate the usefulness of the proposed approach in exploring problems of control in a general dynamic game setting.

关键词： Electromagnetic evasion-pursuit uncertainty feedback control computational methods Kolmogorov and Fokker-Planck equations.

history-dependent percolation on multiplex networks

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National Science Review 2020年第8期7卷 1296-1305页

作者： Ming Li Linyuan Lü youjin Deng Mao-Bin hu hao Wang Matú? Medo h.Eugene Stanley Department of Thermal Science and Energy Engineering University of Science and Technology of China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Alibaba Research Center for Complexity Sciences Hangzhou Normal University Beijing Computational Science Research Center hefei National Laboratory for Physical Sciences at Microscale Department of Modern Physics and CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China Department of Physics and Center for Polymer Studies Boston University

The structure of interconnected systems and its impact on the system dynamics is a much-studied cross-disciplinary topic. Although various critical phenomena have been found in different models, study of the connections between different percolation transitions is still lacking. here we propose a unified framework to study the origins of the discontinuous transitions of the percolation process on interacting networks. The model evolves in generations with the result of the present percolation depending on the previous state, and thus is history-dependent. Both theoretical analysis and Monte Carlo simulations reveal that the nature of the transition remains the same at finite generations but exhibits an abrupt change for the infinite generation. We use brain functional correlation and morphological similarity data to show that our model also provides a general method to explore the network structure and can contribute to many practical applications, such as detecting the abnormal structures of human brain networks.

关键词： percolation multiplex networks critical phenomena brain networks

Antibodies elicited by Newcastle disease virus-vectored h7N9 avian influenza vaccine are functional in activating the complement system

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Journal of Integrative Agriculture 2024年第6期23卷 2052-2064页

作者： Zenglei hu ya huang Jiao hu Xiaoquan Wang Shunlin hu Xiufan Liu Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education of China Yangzhou UniversityYangzhou 225009China Animal Infectious Disease Laboratory School of Veterinary MedicineYangzhou UniversityYangzhou 225009China Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses Yangzhou UniversityYangzhou 225009China

h7N9 subtype avian influenza virus poses a great challenge for poultry *** disease virus(NDV)-vectored h7N9 avian influenza vaccines(NDV_(vec)h7N9)are effective in disease control because they are protective and allow mass *** note,these vaccines elicit undetectable h7N9-specific hemagglutination-inhibition(hI)but high IgG antibodies in ***,the molecular basis and protective mechanism underlying this particular antibody immunity remain ***,immunization with an NDV_(vec)h7N9 induced low anti-h7N9 hI and virus neutralization titers but high levels of hemagglutinin(hA)-binding IgG antibodies in *** residues(S150,G151 and S152)in hA of h7N9 virus were identified as the dominant epitopes recognized by the NDV_(vec)h7N9 immune *** transferred NDV_(vec)h7N9 immune serum conferred complete protection against h7N9 virus infection in *** NDV_(vec)h7N9 immune serum can mediate a potent lysis of hA-expressing and h7N9 virus-infected cells and significantly suppress h7N9 virus *** activities of the serum were significantly impaired after heat-inactivation or treatment with complement inhibitor,suggesting the engagement of the complement ***,mutations in the 150-SGS-152 sites in hA resulted in significant reductions in cell lysis and virus neutralization mediated by the NDV_(vec)h7N9 immune serum,indicating the requirement of antibody-antigen binding for complement ***,antibodies induced by the NDV_(vec)h7N9 can activate antibody-dependent complement-mediated lysis of h7N9 virus-infected cells and complement-mediated neutralization of h7N9 *** findings unveiled a novel role of the complement in protection conferred by the NDV_(vec)h7N9,highlighting a potential benefit of engaging the complement system in h7N9 vaccine design.

关键词： h7N9 subtype avian influenza virus NDV vector vaccine antibody immunity complement protection

An Immersed Boundary-Lattice Boltzmann Prediction for Particle hydrodynamic Focusing in Annular Microchannels

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Chinese Physics Letters 2018年第10期35卷 89-92页

作者： Tao h Meng-Dan hu Si-si Zhou Dong-Ke SUN School of Mechanical Engineering Southeast UniversityNanjing 211189 School of Materials Science and Engineering Southeast UniversityNanjing 211189 School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189

We numerically study the dynamics of particle crystals in annular microchannels by the immersed-boundary（IB）lattice Boltzmann（LB） coupled model, analyze the fluid-particle interactions during the migration of particles,and reveal the underlying mechanism of a particle focusing on the presence of fluid flows. The results show that the Reynolds and Dean numbers are key factors influencing the hydrodynamics of particles. The particles migrate onto their equilibrium tracks by adjusting the Reynolds and Dean numbers. Elliptical tracks of particles during hydrodynamic focusing can be predicted by the IB-LB model. Both the small Dean number and the small particle can lead to a small size of the focusing track. This work would possibly facilitate the utilization of annular microchannel flows to obtain microfluidic flowing crystals for advanced applications in biomedicine and materials synthesis.

关键词： An Immersed Boundary-Lattice Boltzmann Prediction for Particle hydrodynamic Focusing in Annular Microchannels