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Small-divisor Equation of Higher Order with Large Variable Coefficient and Application to the Coupled KdV Equation

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Acta Mathematica Sinica,English Series 2011年第10期27卷 2005-2032页

作者： Mei na gao Jing ZHANG School of Mathematical Sciences Fudan University Shanghai 200433 P. R. China

In this paper, we establish an estimate for the solutions of small-divisor equation of higher order with large variable coefficient. Then by formulating an infinite-dimensional KAM theorem which allows for multiple normal frequencies and unbounded perturbations, we prove that there are many periodic solutions for the coupled KdV equation subject to small Hamiltonian perturbations.

关键词： KAM theorem small-divisor equation with large variable coefficient coupled KdV equation

A Degenerate KAM Theorem for Partial Differential Equations with Unbounded Perturbations

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Acta Mathematica Sinica,English Series 2024年第11期40卷 2719-2734页

作者： Mei na gao Jian Jun LIU School of Mathematics Physics and Statistics Shanghai Polytechnic UniversityShanghai201209P.R.China School of Mathematics Sichuan UniversityChengdu610065P.R.China

In this paper,an infinite dimensional KAM theorem with unbounded perturbations and double normal frequencies is established under qualitative non-degenerate *** is an extension of the degenerate KAM theorem with bounded perturbations by Bambusi,Berti,Magistrelli,and *** applications,for derivative nonlinear Schrödinger equation with periodic boundary conditions,quasi-periodic solutions around constant solutions are obtained.

关键词： KAM theorem derivative nonlinear Schrödinger equation quasi-periodic solutions

Modeling and reachability analysis of synchronizing transitions bounded Petri net systems based upon semi-tensor product of matrices

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The Journal of China Universities of Posts and Telecommunications 2017年第1期24卷 77-86页

作者： gao na Han Xiaoguang Chen Zengqiang Zhang Qing College of Computer and Control Engineering Nankai University Tianjin 300350 China Tianjin Key Laboratory of Intelligent Robotics Tianjin 300350 China College of Science Civil Aviation University of China Tianjin 300300 China

The reachability problem of synchronizing transitions bounded Petri net systems （BPNSs） is investigated in this paper by constructing a mathematical model for dynamics of BPNS. Using the semi-tensor product （STP） of matrices, the dynamics of BPNSs, which can be viewed as a combination of several small bounded subnets via synchronizing transitions, are described by an algebraic equation. When the algebraic form for its dynamics is established, we can present a necessary and sufficient condition for the reachability between any marking （or state） and initial marking. Also, we give a corresponding algorithm to calculate all of the transition paths between initial marking and any target marking. Finally, an example is shown to illustrate proposed results. The key advantage of our approach, in which the set of reachable markings of BPNSs can be expressed by the set of reachable markings of subnets such that the big reachability set of BPNSs do not need generate, is partly avoid the state explosion problem of Petri nets （PNs）.

关键词： reachability Petri nets BPNSs semi-tensor product (STP) of matrices synchronizing transitions

Small G Rac1 is involved in replication cycle of dengue serotype 2 virus in EAhy926 cells via the regulation of actin cytoskeleton

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Science China(Life Sciences) 2016年第5期59卷 487-494页

作者： Jing Zhang na Wu na gao Wenli Yan Ziyang Sheng Dongying Fan Jing An Department of Microbiology School of Basic Medical Sciences Capital Medical University Beijing 100069 China Center of Epilepsy Beijing Institute for Brain Disorders Beijing 100069 China

Bleeding is a clinical characteristic of severe dengue and may be due to increased vascular permeability. However, the patho- genesis of severe dengue remains unclear. In this study, we showed that the Racl-microfilament signal pathway was involved in the process of DENV serotype 2 （DENV2） infection in EAhy926 cells. DENV2 infection induced dynamic changes in actin organization, and treatment with Cytochalasin D or Jasplakinolide disrupted microfilament dynamics, reduced DENV2 entry, and inhibited DENV2 assembly and maturation. Racl activities decreased during the early phase and gradually increased by the late phase of infection. Expression of the dominant-negative form of Racl promoted DENV2 entry but inhibited viral as- sembly, maturation and release. Our findings demonstrated that Racl plays an important role in the DENV2 life cycle by reg- ulating actin reorganization in EAhy926 cells. This finding provides further insight into the pathogenesis of severe dengue.

关键词： dengue virus small Rho GTPase Racl actin vascular endothelial cells

Effects of sports on school adaptability, resilience and cell phone addiction tendency of high school students

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World Journal of Psychiatry 2023年第8期13卷 563-572页

作者： Li-Qiang Zhang Hui-na gao School of Physical Education Xizang Minzu UniversityXianyang 712082Shaanxi ProvinceChina The PE Department Shaanxi Institute of International Trade&CommerceXi’an 712046Shaanxi ProvinceChina

BACKGROUND Sport help promote healthy physical and mental development of high school *** date,there have been few studies on the effect of sport on school adaptability,resilience and cell phone addiction tendency of high school *** To explore the effects of sports on school adaptability,resilience and cell phone addiction of high school *** A stratified random sampling method was used to select 600 students from two high schools in Lhasa,and Physical Activity Rating Scale,School Adjustment Scale for High School Students,Chinese Adolescents Resilience Scale,and Mobile Phone Addiction Index were used for field questionnaire *** Sport was positively correlated with school adaptability and resilience(P<0.01),school adaptability was positively correlated with resilience(P<0.01)and cell phone addiction was negatively correlated with sports,school adaptability and resilience(P<0.01).The direct effect of sport on cell phone addiction was significant(P<0.001),accounting for 20.51%of the total *** mediating effect of school adaptability on sport and cell phone addiction was significant(P<0.001),accounting for 17.38%and 35.36%of the total effect value,*** adjustment and resilience had a significant chain-mediated effect on sport and cell phone addiction(P<0.001),accounting for 26.75%of the total *** Sport affected the cell phone addiction tendency of senior high school students through the mediating effect of school adaptability and resilience,and through the chain mediation effect of both.

关键词： Sport High school students School adaptability Resilience Cell phone addiction

Tris(2,2'-bipyridyl)ruthenium(Ⅱ) electrochemiluminescence (ECL) enhanced by rutin on platinum electrode

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Chinese Chemical Letters 2007年第5期18卷 561-564页

作者： Da Xu Zhong Lan gao na Li Ke An Li Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Ru（bpy）3^2＋ electrochemiluminescence （ECL） was applied to determination of rutin. ECL intensity of Ru（bpy）3^2＋ could be enhanced in the presence of rufin in basic solution on platinum electrode. At pH 9.9, lig... 详细信息

关键词： Ru(bpy)3^2+ Electrochemiluminescence Rutin Platinum electrode

Micro air vehicle-motivated computational biomechanics in bio-flights:aerodynamics,flight dynamics and maneuvering stability

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Acta Mechanica Sinica 2010年第6期26卷 863-879页

作者： Hao Liu Toshiyuki nakata na gao Masateru Maeda Hikaru Aono Wei Shyy Graduate School of Engineering.Chiba University Chiba 263-8522Japan Department of Aerospace Engineering.University of Michigan Ann ArborMI 48109USA Department of Mechanical Engineering The Hong Kong University of Science and TechnologyClear Water Bay.KowloonHong Kong China

Aiming at developing an effective tool to unveil key mechanisms in bio-flight as well as to provide guidelines for bio-inspired micro air vehicles（MAVs） design,we propose a comprehensive computational framework,which integrates aerodynamics,flight dynamics,vehicle stability and *** framework consists of（1） a navier-Stokes unsteady aerodynamic model;（2） a linear finite element model for structural dynamics;（3） a fluidstructure interaction（FSI） model for coupled flexible wing aerodynamics aeroelasticity;（4） a free-flying rigid body dynamic（RBD） model utilizing the Newtonian-Euler equations of 6DoF motion;and（5） flight simulator accounting for realistic wing-body morphology,flapping-wing and body kinematics,and a coupling model accounting for the nonlinear 6DoF flight dynamics and stability of insect flapping *** are presented based on hovering aerodynamics with rigid and flexible wings of hawkmoth and *** present approach can support systematic analyses of bio- and bio-inspired flight.

关键词： Micro air vehicle Bio-flight Computational mechanics Integrative biomechanics

A melatonin-based targetable fluorescent probe for screening of tumor cells and real-time imaging of glutathione fluctuations in tumor cells

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Chinese Chemical Letters 2022年第5期33卷 2527-2531页

作者： Xiwei Li Caiyun Liu na gao Wenlong Sheng Baocun Zhu School of Water Conservancy and Environment University of JinanJi’nan 250022China Biology Institute Qilu University of Technology(Shandong Academy of Sciences)Ji’nan 250103China

Glutathione(GSH)is a key maintainer of cellular redox balance and plays an important role in many physiological *** example,GSH has been widely implicated in cancer initiation,progression and ***,the concentrations of GSH in tumor cells can influence drug *** the serious harmfulness of cancer and the important roles of GSH in cancer,it has great significance to devel-opment probes for screening of tumor cells and real-time monitoring of GSH fluctuations in tumor ***,no targetable probe for reversible imaging of GSH in tumor cells has been ***,we constructed a melatonin-based targetable and reversible fluorescent probe(GR-MT)for screening of tumor cells and real-time imaging of GSH fluctuations in tumor *** probe uses coumarin as the skeleton,Michael addition reaction as the reaction mechanism,and melatonin as the targeted groups of tumor *** experimental results demonstrate this probe has many advantages including high selec-tivity,satisfactory sensitivity,excellent reversible ability,rapid reaction speed,and outstanding targetabil-ity of tumor ***,this study provides a promising tool for tumor cells screening and real-time detection of GSH fluctuations in specific tumor cells.

关键词： Glutathione Reversible detection Fluorescent probe Tumor cells screening Melatonin

Enzyme-catalyzed asymmetric domino aza-Michael/aldol reaction for the synthesis of 1,2-dihydroquinolines using pepsin from porcine gastric mucosa

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Chinese Chemical Letters 2016年第6期27卷 964-968页

作者： Xue-Dong Zhang na gao Zhi Guan Yan-Hong He Key Laboratory of Applied Chemistry of Chongqing Municipality School of Chemistry and Chemical Engineering Southwest University

An unprecedented enzyme-catalyzed asymmetric domino aza-Michael/aldol reaction of 2-aminobenzaldehyde and a,b-unsaturated aldehydes is achieved. Pepsin from porcine gastric mucosa provided mild and efficient access to diverse substituted 1,2-dihydroquinolines in yields of 38%–97% with 6%–24%enantiomeric excess（ee）. This work not only provides a novel method for the synthesis of dihydroquinoline derivatives, but also promotes the development of enzyme catalytic promiscuity.

关键词： Pepsin Biocatalysis Domino aza-Michael/aldol reaction 1 2-Dihydroquinolines Enzyme catalytic promiscuity