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Regulation of developmental and environmental signaling by interaction between microtubules and membranes in plant cells

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Protein & Cell 2016年第2期7卷 81-88页

作者： qun zhang Wenhua zhang College of Life Sciences State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing AgriculturalUniversity Nanjing 210095 China

Cell division and expansion require the ordered arrangement of microtubules, which are subject to spatial and temporal modifications by developmental and environmental factors. Understanding how signals translate to changes in cortical microtubule organization is of fundamental importance. A defining feature of the cortical microtubule array is its association with the plasma membrane; modules of the plasma membrane are thought to play important roles in the mediation of microtubule organization. In this review, we highlight advances in research on the regulation of cortical microtubule organization by membrane-associated and membrane-tethered proteins and lipids in response to phytohormones and stress. The transmembrane kinase receptor Rho-like guanosine triphosphatase, phospholipase D, phosphatidic acid, and phosphoinositides are discussed with a focus on their roles in microtubule organization.

关键词： abiotic stresses cortical microtubule,lipids plasma membrane

Existence and Regularity of Solution to the Generalized Tricomi Equation with a Singular Initial Datum at a Point

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Acta Mathematica Sinica,English Series 2012年第6期28卷 1135-1154页

作者： Kang qun zhang Department of Mathematics&IMS Nanjing University

In this paper, we study the existence and regularity of a solution to the initial datum problem of a semilinear generalized Tricomi equation in mixed-type initial datum on the degenerate plane is smooth away from the origin, domain. We suppose that an and has a conormal singularity at this point, then we show that in some mixed-type domain, the solution exists and is conormal with respect to the characteristic conic surface which is issued from the origin and has a cusp singularity.

关键词： Generalized Tricomi equation confluent hypergeometric function existence conormalregularity cusp singularity

A Note on Initial Value Problem for the Generalized Tricomi Equation in a Mixed-type Domain

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Acta Mathematica Sinica,English Series 2013年第8期29卷 1581-1596页

作者： Kang qun zhang Department of Mathematics and Physics Nanjing Institute of Technology

In this paper, we study the well-posedness of initial value problem for n-dimensional gener-alized Tricomi equation in the mixed-type domain {（t,x）：t∈[1,＋∞）,x∈Rn} with the initial data given on the line t=1 in Hadamard＇s sense. By taking partial Fourier transformation, we obtain the explicit expression of the solution in terms of two integral operators and further establish the global estimate of such a solution for a class of initial data and source term. Finally, we establish the global solution in time direction for a semilinear problem used the estimate.

关键词： Generalized Tricomi equation semilinear initial value problem mixed-type domain

Existence of a-Cores for Games Without Compact Assumptions

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Journal of the Operations Research Society of China 2024年第2期12卷 520-527页

作者： Hai-qun zhang School of International Economics and Trade Shanghai Lixin University of Accounting and Fin Shanghai201209China

Following the representation of Kajii(J Econ Theory 56:194-205,1992),we provide some existence theorems ofα-cores for games without ordered preferences and compact *** applications,we obtain some existence results of... 详细信息

关键词： α-Core Existence Preference Noncompactness

A robust joint frequency spectrum and power allocation strategy in a coexisting radar and communication system

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Chinese Journal of Aeronautics 2024年第10期37卷 393-409页

作者： Haowei zhang Weijian LIU qun zhang Taiyong FEI Air and Missile Defense School Air Force Engineering UniversityXi’an 710051China Air Force Early Warning Academy Wuhan 410039China Information and Navigation School Air Force Engineering UniversityXi’an 710082China

The resource allocation technique is of great significance in achieving frequency spectrum coexistence in Joint Radar-Communication(JRC) systems, by which the problem of radio frequency spectrum congestion can be well alleviated. A Robust Joint Frequency Spectrum and Power Allocation(RJFSPA) strategy is proposed for the Coexisting Radar and Communication(CRC)system. Specifically, we consider the uncertainty of target Radar Cross Section(RCS) and communication channel gain to formulate a bi-objective optimization model. The joint probabilities that the Cramér-Rao Lower Bound(CRLB) of each target satisfying the localization accuracy threshold and the Communication Data Ratio(CDR) of each user satisfying the communication threshold are simultaneously maximized, under the constraint of the total power budget. A Three-Stage Alternating Optimization Method(TSAOM) is proposed to obtain the Best-Known Pareto Subset(BKPS) of this problem, where the frequency spectrum, radar power, and communicator power are allocated using the greedy search and standard convex optimization methods, respectively. Simulation results confirm the effectiveness of the proposed RJFSPA strategy, compared with the resource allocation methods in a uniform manner and that ignores the uncertainties. The efficiency of the TSAOM is also verified by the comparison with the exhaustive search-based method.

关键词： Radar and communication system Bi-objective optimization Resource allocation Cramér-Rao lower bound Communication data ratio

Nonexistence of Majorana fermions in Kerr-Newman type spacetimes with nontrivial charge

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Chinese Physics C 2024年第11期48卷 156-161页

作者： He-qun zhang Xiao zhang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

We show that the Dirac equation is separated into four differential equations for time-periodic Majorana fermions in Kerr-Newman and Kerr-Newman-(A)dS *** they cannot be transformed into radial and angular equations,the four differential equations yield two algebraic *** the electric or magnetic charge is nonzero,they conclude that there is no differentiable time-periodic Majorana fermions outside the event horizon in Kerr-Newman and Kerr-Newman-AdS spacetimes,or between the event horizon and the cosmological horizon in Kerr-Newman-dS spacetime.

关键词： Dirac equation Majorana fermion Kerr-Newman-type spacetime

A Note on the Complexity of Proximal Iterative Hard Thresholding Algorithm

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Journal of the Operations Research Society of China 2015年第4期3卷 459-473页

作者： Xue zhang Xiao-qun zhang Department of Mathematics Shanghai Jiao Tong UniversityShanghai 200240China Institute of Natural Sciences Shanghai Jiao Tong UniversityShanghai 200240China

The iterative hard thresholding(IHT)algorithm is a powerful and efficient algorithm for solving l_(0)-regularized problems and inspired many applications in sparse-approximation and image-processing ***,some convergence results are established for the proximal scheme of IHT,namely proximal iterative hard thresholding(PIHT)algorithm(Blumensath and Davies,in J Fourier Anal Appl 14:629–654,2008;Hu et al.,Methods 67:294–303,2015;Lu,Math Program 147:125–154,2014;Trzasko et al.,IEEE/SP 14th Workshop on Statistical Signal Processing,2007)on solving the related l_(0)-optimization ***,the complexity analysis for the PIHT algorithm is not well *** this paper,we aim to provide some complexity estimations for the PIHT *** particular,we show that the complexity of the sequential iterate error is at o(1/k).Under the assumption that the objective function is composed of a quadratic convex function and l_(0)regularization,we show that the PIHT algorithm has R-linear convergence ***,we illustrate some applications of this algorithm for compressive sensing reconstruction and sparse learning and validate the estimated error bounds.

关键词： l_(0)Regularization Iterative hard thresholding Proximal algorithm Convergence rate R-linear

Isometric Immersions of Higher Codimension in to the Product S~κ×H^(n+p-k)

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Acta Mathematica Sinica,English Series 2014年第12期30卷 2146-2160页

作者： Xing Xiao LI Tian qun zhang Department of Mathematics He'nan Normal University Luoyang No.43 Middle School

In this paper,we obtain a sufficient and necessary condition for a simply connected Riemannian manifold（M^n,g） to be isometrically immersed,as a submanifold with codimension p 〉 1,into the product S^k×H^n＋p＋k of... 详细信息

关键词： Isometric immersions of higher codimension product structure spheres and hyperboloids

Asymptotic behavior and blowup for two generalized Ginzburg-Landau type equations with several nonlinear source terms

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International Journal of Biomathematics 2017年第2期10卷 235-247页

作者： Shoubo Jin Zufeng zhang qun zhang School of Mathematics and Statistics Suzhou University Suzhou 233000 Anhui P. R. China

In this paper, the long-time behavior and blowup of solutions for two generalized Ginzburg-Landau type equations with several nonlinear source terms are investigated. First, the conditions in which the solutions of the two equations are positive are ana- lyzed by using Green＇s function. According to the characteristics of nonlinear terms, four different functionals are constructed for solving the problems. Finally, we obtain the long-time behavior and finite-time blowup of solutions for the initial and boundary value problem by using these functionals.

关键词： Asymptotic behavior blowup Ginzburg-Landau type equations.