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In this paper, we prove nonexistence of positive supersolutions of a semilinear equation − div ( A ( x ) ∇ u ) + b ( x ) ⋅ ∇ u = f ( u ) in exterior domains in R n ( n ≥ 3 ), where A ( x ) is bounded and uniformly elliptic, b ( x ) = O ( | x | − 1 ) , div b = 0 and f is a continuous and positive function in ( 0 , ∞ ) satisfying f ( u ) ∼ u q as u → 0 with q ≤ n / ( n − 2 ) . Furthermore, we investigate general conditions on b and f for nonexistence of positive supersolutions. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we revisit elliptic estimates invariant under domain expansion. We improve the invariant elliptic estimates in the previous paper [Y. Cho, T. Ozawa, Y. Shim, Calc. Var. PDE 34 (2009) 321–339] via gradient estimate and discuss an application to the Lamé system. [Copyright &y& Elsevier]

Abstract: In this paper, we will prove some uniqueness theorems of meromorphic functions whose derivatives share four distinct small functions. The results in this paper improve those given by R. Nevanlinna, L. Yang, G.D. Qiu, and other authors. An example is provided to show that the results in this paper are best possible. [Copyright &y& Elsevier]

Abstract: In this paper, we deal with the problem of uniqueness and weighted sharing of two meromorphic functions with their first derivatives having the same fixed points with the same multiplicities. The results in this paper improve those given by K. Tohge, Xiao-Min Li and Hong-Xun Yi. [Copyright &y& Elsevier]

Abstract: In this paper, by means of a series of counterexamples, we study in a systematic way the relationships among (pseudo, quasi) α-preinvexity, (strict, strong, pseudo, quasi) α-invexity and (strict, strong, pseudo, quasi) αη-monotonicity. Results obtained in this paper can be viewed as a refinement and improvement of the results of Noor and Noor [M.A. Noor, K.I. Noor, Some characterizations of strongly preinvex functions, J. Math. Anal. Appl. 316 (2006) 697–706]. [Copyright &y& Elsevier]

Abstract: In this paper we complete a distributional Fourier analysis developed by Howell in a serie of papers. We investigate convolution operators in the corresponding distribution spaces. [Copyright &y& Elsevier]

Abstract: In this paper, we suggest and analyze a new inexact proximal point method for solving general variational inequalities, which can be considered as an implicit predictor–corrector method. An easily measurable error term is proposed with further relaxed error bound and an optimal step length is obtained by maximizing the profit-function and is dependent on the previous points. Our results include several known and new techniques for solving variational inequalities and related optimization problems. Results obtained in this paper can be viewed as an important improvement and refinement of the previously known results. Preliminary numerical experiments are included to illustrate the advantage and efficiency of the proposed method. [Copyright &y& Elsevier]

In this paper, we first establish collective fixed points theorems for a family of multivalued maps with or without assuming that the product of these multivalued maps is Φ-condensing. As an application of our collective fixed points theorem, we derive the coincidence theorem for two families of multivalued maps defined on product spaces. Then we give some existence results for maximal elements for a family of LS-majorized multivalued maps whose product is Φ-condensing. We also prove some existence results for maximal elements for a family of multivalued maps which are not LS-majorized but their product is Φ-condensing. As applications of our results, some existence results for equilibria of abstract economies are also derived. The results of this paper are more general than those given in the literature. [Copyright &y& Elsevier]

In this paper we prove that spectral synthesis holds for a variety on an Abelian group if spectral analysis holds on it and the residue ring of the annihilator of the variety is a Noether ring. This extends the fundamental result of M. Lefranc about spectral synthesis on finitely generated Abelian groups. [ABSTRACT FROM AUTHOR]

This paper addresses the properties of the C 0 -semigroup generated by the reparable system with finite repair time. In particular, it can be shown that the C 0 -semigroup is eventually differentiable and eventually compact, which is not true for the case when the repair time is infinite, as discussed in [9] and [11] . [ABSTRACT FROM AUTHOR]

In this paper, we study the Cauchy problem of the Camassa–Holm equation. We present a well-posedness result and a blow-up criterion of solutions in the inhomogeneous Triebel–Lizorkin spaces. [ABSTRACT FROM AUTHOR]

This paper is concerned with Wold-type decomposition for regular operators whose orbits under any vector satisfy some growth conditions. Several results on left invertible operators close to isometries are extended. We also give numerous results on the Moore–Penrose inverse for regular operators in this particular setting. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we provide an existence result of periodic solutions to planar systems having a repulsive singularity on both the axes. We require a nonresonance assumption, related to the spectrum of the periodic problem associated to the Steen's planar system which is isochronous (see [15]). As a particular case we obtain the existence of periodic solutions to a periodically perturbed Steen's planar system. [Copyright &y& Elsevier]

Abstract: A celebrated theorem of Coburn asserts that, on the setting of the Hardy space, if a Toeplitz operator is nonzero, then either it is one-to-one or its adjoint operator is one-to-one. In this paper, we show that an analogous result holds for Toeplitz operators acting on the Dirichlet space. [Copyright &y& Elsevier]

Abstract: Periodic travelling wave solutions of reaction–diffusion equations were studied by many authors. The type reaction–diffusion system is a notable special model that admits explicit periodic travelling wave solutions and was introduced by Kopell and Howard in 1973. There are now similar systems which are investigated by means of autonomous dynamics. In contrast, there are few papers which are concerned with non-autonomous cases. For this reason, we apply Mawhin’s continuation theorem to derive the existence of periodic travelling wave solutions for non-autonomous systems, and we describe the ‘disappearance’ of periodic travelling wave solutions under special situations. Our main result is also illustrated by examples. [Copyright &y& Elsevier]

Abstract: In this paper, we give new characterization of the classical Morrey space. Complementary global Morrey-type spaces are introduced. It is proved that for particular values of parameters these spaces give new pre-dual space of the classical Morrey space. We also show that our new pre-dual space of the Morrey space coincides with known pre-dual spaces. [Copyright &y& Elsevier]

Abstract: The main aim of this paper is the investigation of conditions under which a locally convex quasi ⁎-algebra attains sufficiently many -continuous ⁎-representations in , to separate its points. Having achieved this, a usual notion of bounded elements on rises. On the other hand, a natural order exists on related to the topology τ, that also leads to a kind of bounded elements, which we call “order bounded”. What is important is that under certain conditions the latter notion of boundedness coincides with the usual one. Several nice properties of order bounded elements are extracted that enrich the structure of locally convex quasi ⁎-algebras. [Copyright &y& Elsevier]

Abstract: In this paper, we establish a necessary and sufficient condition for the convexity of the complete elliptic integrals of the first kind with respect to Hölder means. [Copyright &y& Elsevier]

Abstract: In this paper, the property of linearly dependence of solutions and for higher order linear differential equation where () are entire periodic coefficients and () is the dominant coefficient, is investigated. [Copyright &y& Elsevier]

Abstract: By now the -spectra of self-conformal measures satisfying the so-called open set condition are well understood. However, if the open set condition is not satisfied, then almost nothing is known. In this paper we compute the mixed -spectra for self-conformal measures, which have bound distortion property and satisfy the weak separation condition. [Copyright &y& Elsevier]

Abstract: In this paper viability results for nonlinear fractional differential equations with the Caputo derivative are proved. We give the sufficient condition that guarantees fractional viability of a locally closed set with respect to nonlinear function. As an example we discuss positivity of solutions, particularly in linear case. [Copyright &y& Elsevier]

Abstract: In this paper second order quasilinear ordinary differential equations are considered, and a necessary and sufficient condition for the existence of a slowly growing positive solution is established. Moreover, the precise asymptotic forms as of slowly growing positive solutions and slowly decaying positive solutions are obtained. [Copyright &y& Elsevier]

Abstract: In this paper we investigate and Sobolev boundedness of a certain class of pseudodifferential operators with non-regular symbols. We employ regularisation methods, namely convolution with a net of mollifiers , and we study the corresponding net of pseudodifferential operators providing and Sobolev estimates which relate the parameter ε with the non-regularity of the symbol. [Copyright &y& Elsevier]

Abstract: In this paper, we deal with the global existence and nonexistence of solutions to a nonlinear diffusion system coupled via nonlinear boundary flux. By constructing various kinds of sub- and super-solutions and using the basic properties of M-matrix, we give the necessary and sufficient conditions for global existence of nonnegative solutions. The critical curve of Fujita type is conjectured with the aid of some new results, which extend the recent results of Wang et al. [Nonlinear Anal. 71 (2009) 2134–2140] and Li et al. [J. Math. Anal. Appl. 340 (2008) 876–883] to more general equations. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the invertibility of nonnegative Hamiltonian operator with unbounded entries is studied, and the sufficient conditions for the everywhere defined bounded invertibility of nonnegative Hamiltonian operator are obtained. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we investigate the uniqueness of meromorphic functions in the unit disc and consider the relation between the Borel points and shared-values of meromorphic functions in an angular domain. [Copyright &y& Elsevier]

Abstract: In this paper we present a new primal-dual path-following interior-point algorithm for semidefinite optimization. The algorithm is based on a new technique for finding the search direction and the strategy of the central path. At each iteration, we use only full Nesterov–Todd step. Moreover, we obtain the currently best known iteration bound for the algorithm with small-update method, namely, , which is as good as the linear analogue. [Copyright &y& Elsevier]

Abstract: This paper is devoted to the existence and properties of solutions of the following class of nonlinear elliptic differential equations , , . We prove existence of positive solutions vanishing at positive infinity. Our approach is based on the subsolution and supersolution method. The nonlinearity f covers both sublinear and superlinear cases and does not necessarily satisfy . The asymptotic behavior of solutions is also described. [Copyright &y& Elsevier]

Abstract: In this paper, essentially strongly order-preserving and conditionally set-condensing semiflows are considered. Obtained is a new type of generic quasi-convergence principles implying the existence of an open and dense set of stable quasi-convergent points when the state space is order bounded. The generic quasi-convergence principles are then applied to essentially cooperative and irreducible systems in the forms of ordinary differential equations and delay differential equations, giving some results of theoretical and practical significance. [Copyright &y& Elsevier]

Abstract: In this paper, we will study the isometric extension problem for -spaces and prove that every surjective isometry from the unit sphere of onto that of a Banach space E can be extended to a linear surjective isometry from onto E. Moreover, we introduce the approximate isometric extension problem and show that, if E and F are Banach spaces and E satisfies the property (m) (special cases are , and ), then every bijective ϵ-isometry between the unit spheres of E and F can be extended to a bijective 5ϵ-isometry between their closed unit balls. At last, we will give an example to show that the surjectivity assumption cannot be omitted. Using this, we solve the non-surjective isometric extension problem in the negative. [Copyright &y& Elsevier]

Abstract: In this paper, we show that minimization problems involving sublinear regularizing terms are ill-posed, in general, although numerical experiments in image processing give very good results. The energies studied here are inspired by image restoration and image decomposition. Rewriting the nonconvex sublinear regularizing terms as weighted total variations, we give a new approach to perform minimization via the well-known Chambolle''s algorithm. The approach developed here provides an alternative to the well-known half-quadratic minimization one. [Copyright &y& Elsevier]

Abstract: Let and be polynomials of degree respectively n and less than n such that A result due to Q.I. Rahman states that In this paper, we slightly improve the above inequality and discuss several sharpness aspects, including all cases of equality. [Copyright &y& Elsevier]

Abstract: In the present paper we show some results concerning the orbital stability of dnoidal standing wave solutions and orbital instability of cnoidal standing wave solutions to the following Klein–Gordon equation: We also present a result of orbital instability of snoidal standing wave solutions to the Klein–Gordon equation The main tool to obtain these results is the classical Grillakis, Shatah and Strauss'' theory in the periodic context. [Copyright &y& Elsevier]

Abstract: In this paper, we improve contractivity conditions of solutions for the positive equilibrium of the following differential equation with piecewise constant arguments: where is a nonnegative continuous function on , , , , , and . In particular, for the case and , we really improve the known three type conditions of the contractivity for solutions of this model (see for example, [Y. Muroya, A sufficient condition on global stability in a logistic equation with piecewise constant arguments, Hokkaido Math. J. 32 (2003) 75–83]). For the other case and , under the condition , the obtained result partially improves the known results on the contractivity of solutions for the positive equilibrium of this model given by the author [Y. Muroya, Persistence, contractivity and global stability in logistic equations with piecewise constant delays, J. Math. Anal. Appl. 270 (2002) 602–635] and others. [Copyright &y& Elsevier]

Abstract: This paper extends the Hille–Phillips functional calculus and rational approximations results due to R. Hersh, T. Kato, P. Brenner, and V. Thomée to generators of bi-continuous semigroups. The method yields error estimates for rational time-discretization schemes for such semigroups, in particular for dual semigroups, Feller semigroups such as the Ornstein–Uhlenbeck semigroup, the heat semigroup, semigroups induced by nonlinear flows, implemented semigroups, and evolution semigroups. Furthermore, the results provide error estimates for a new class of inversion formulas for the Laplace transform. [Copyright &y& Elsevier]

Abstract: In this paper we discuss a certain class of sets of generators for a full Hilbert -module which characterize Hilbert -modules over the -algebra of compact operators. An example of such sets of generators are orthonormal bases. [Copyright &y& Elsevier]

Abstract: In this paper, two conjugate dual problems based on weak efficiency to a constrained vector optimization problem are introduced. Some inclusion relations between the dual objective mappings and the properties of the Lagrangian maps and their saddle points for primal problem are discussed. Gap functions for a vector equilibrium problem are established by using the weak and strong duality. [Copyright &y& Elsevier]

Abstract: In this paper we consider the stability for a class of jump-diffusions with Markovian switching. We first construct them successively and show that they can be associated with some appropriate generators and they are non-explosive. We then prove their Feller continuity by the coupling methods. Furthermore, we also prove their strong Feller continuity by making use of the relation between the transition probabilities of jump-diffusions and the corresponding diffusions. Finally, we also investigate their exponential ergodicity. [Copyright &y& Elsevier]

Abstract: Drewnowski and Paúl proved in [L. Drewnowski, P.J. Paúl, The Nikodým property for ideals of sets defined by matrix summability methods, Rev. R. Acad. Cienc. Exactas Fís. Nat. (Esp.) 94 (2000) 485–503] that for any strongly nonatomic submeasure η on the power set of the ideal has the Nikodym property (NP); in particular, this result applies to densities defined by strongly regular matrices A. Grahame Bennett and the authors stated in [G. Bennett, J. Boos, T. Leiger, Sequences of 0''s and 1''s, Studia Math. 149 (2002) 75–99] that the strong null domain of any strongly regular matrix A has the Hahn property (HP). Moreover, Stuart and Abraham [C.E. Stuart, P. Abraham, Generalizations of the Nikodym boundedness and Vitali–Hahn–Saks theorems, J. Math. Anal. Appl. 300 (2) (2004) 351–361] pointed out that the said results are in some sense dual and that the last one follows from the first one by considering the density (defined by A) as submeasure on and the ideal as well by identifying with the set χ of sequences of 0''s and 1''s. In this paper we aim at a better understanding of the intimated duality and at a characterization of those members of special classes of matrices A such that has NP (equivalently, has HP). [Copyright &y& Elsevier]

Abstract: In this paper we prove new identities in the Catalan triangle whose entry is defined by In fact, we show some new identities involving the well-known Catalan numbers, and specially the identity that appears in a problem related with the dynamical behavior of a family of iterative methods applied to quadratic polynomials. [Copyright &y& Elsevier]

Abstract: In this paper, we prove an important inequality and investigate some new calculating problems of random fixed point index, and generalize famous theorem by means of the theory of random fixed point index. [Copyright &y& Elsevier]

Abstract: In this paper, characterizations of the existence of the directional derivative and second-order parabolic directional derivative of a locally Lipschitzian function are established. These characterizations involve the adjacent cone and second-order adjacent set of the graph of the function. [Copyright &y& Elsevier]

Abstract: Let and be analytic in the unit disk. The Hadamard product of f and g is defined by . This paper gives some characterizations of functions in spaces in terms of the Hadamard products. [Copyright &y& Elsevier]

Abstract: In this paper, the connection between -analogue of special functions and representations of certain two parameter quantum algebras has been developed. The realizations of the representations of these quantum algebras are in terms of -derivative operators. The matrix elements of these representations are computed in terms of the generalized -hypergeometric series. This leads to the developments in the theory of -special functions. [Copyright &y& Elsevier]

Abstract: In this paper we study the hyponormality and subnormality of 2-variable weighted shifts using the Schur product techniques in matrices. As applications, we generalize the result in [R. Curto, J. Yoon, Jointly hyponormal pairs of subnormal operators need not be jointly subnormal, Trans. Amer. Math. Soc. 358 (2006) 5135–5159, Theorem 5.2] and give a non-trivial, large class satisfying the Curto–Muhly–Xia conjecture [R. Curto, P. Muhly, J. Xia, Hyponormal pairs of commuting operators, Oper. Theory Adv. Appl. 35 (1988) 1–22] for 2-variable weighted shifts. Further, we give a complete characterization of hyponormality and subnormality in the class of flat, contractive, 2-variable weighted shifts with the condition that the norm of the 0th horizontal 1-variable weighted shift of T is a given constant. [Copyright &y& Elsevier]

Abstract: In this paper, we study the normality of a family of meromorphic functions and obtain some normality results for meromorphic functions, which improve and generalize the related results of Gu, Bergweiler and Lin. [Copyright &y& Elsevier]

Abstract: In this paper, we study the existence of stationary solutions to the Vlasov–Poisson–Boltzmann system when the background density function tends to a positive constant with a very mild decay rate as . In fact, the stationary Vlasov–Poisson–Boltzmann system can be written into an elliptic equation with exponential nonlinearity. Under the assumption on the decay rate being for some , it is shown that this elliptic equation has a unique solution. This result generalizes the previous work [R. Glassey, J. Schaeffer, Y. Zheng, Steady states of the Vlasov–Poisson–Fokker–Planck system, J. Math. Anal. Appl. 202 (1996) 1058–1075] where the decay rate is assumed. [Copyright &y& Elsevier]

Abstract: Some new generalizations of the Hilbert integral inequality by introducing real functions and . The results of this paper reduce to those of the corresponding inequalities proved by Gao [Mingzhe Gao, On Hilbert''s integral inequality, Math. Appl. 11 (3) (1998) 32–35]. Some applications are considered. [Copyright &y& Elsevier]

Abstract: In this work we present an extension to arbitrary unital Banach algebras of a result due to Phillips [R.S. Phillips, Spectral theory of semigroups of linear operators, Trans. Amer. Math. Soc. 71 (1951) 393–415] (Theorem 1.1) which provides sufficient conditions assuring the uniform continuity of strongly continuous semigroups of linear operators. It implies that, when dealing with the algebra of bounded operators on a Banach space, the conditions of Phillips''s theorem are also necessary. Moreover, it enables us to derive necessary and sufficient conditions in terms of essential spectra which guarantee the uniform continuity of strongly continuous semigroups. We close the paper by discussing the uniform continuity of strongly continuous groups acting on Banach spaces with separable duals such that, for each , the essential spectrum of is a finite set. [Copyright &y& Elsevier]

Abstract: In this paper, we deal with the problem of framing 2-variable 2-parameter Bessel functions (2V2PBF) into the context of the representation of the 3-dimensional Lie algebra . Further, we derive generating relations and identities involving 2V2PBF. Furthermore, we deduce some new and known relations involving various other forms of generalized Bessel functions (GBF) and Bessel functions (BF) as applications of these results. [Copyright &y& Elsevier]