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991.
Yuli Xie Yidong Liu Alison Rinderspacher Donald W. Landry 《Tetrahedron letters》2008,49(14):2320-2323
An efficient synthesis of a series of N-8-quinolinyl benzenesultams as novel NF-κB inhibitors was described via diazotization-induced cyclization of easily accessible N-8-quinolinyl-2-aminobenzenesulfonamides. 相似文献
992.
This expository article is devoted to the local theory of ultradifferentiable classes of functions, with a special emphasis on the quasianalytic case. Although quasianalytic classes are well-known in harmonic analysis since several decades, their study from the viewpoint of differential analysis and analytic geometry has begun much more recently and, to some extent, has earned them a new interest. Therefore, we focus on contemporary questions closely related to topics in local algebra. We study, in particular, Weierstrass division problems and the role of hyperbolicity, together with properties of ideals of quasianalytic germs. Incidentally, we also present a simplified proof of Carleman's theorem on the non-surjectivity of the Borel map in the quasianalytic case. 相似文献
993.
L. Bernal-González M. C. Calderón-Moreno J. A. Prado-Bassas 《Integral Equations and Operator Theory》2008,60(1):1-11
The existence of infinite dimensional closed linear spaces of holomorphic functions f on a domain G in the complex plane such that Tf has dense images on certain subsets of G, where T is a continuous linear operator, is analyzed. Necessary and sufficient conditions for T to have the latter property are provided and applied to obtain a number of concrete examples: infinite order differential
operators, composition operators and multiplication operators, among others.
This work was supported in part by the Plan Andaluz de Investigación de la Junta de Andalucía FQM-127 and by MEC DGES Grants
MTM2006-13997-C02-01 and MTM2004-21420-E. 相似文献
994.
The notions of exhausters were introduced in (Demyanov, Exhauster of a positively homogeneous function, Optimization 45, 13–29
(1999)). These dual tools (upper and lower exhausters) can be employed to describe optimality conditions and to find directions
of steepest ascent and descent for a very wide range of nonsmooth functions. What is also important, exhausters enjoy a very
good calculus (in the form of equalities). In the present paper we review the constrained and unconstrained optimality conditions
in terms of exhausters, introduce necessary and sufficient conditions for the Lipschitzivity and Quasidifferentiability, and
also present some new results on relationships between exhausters and other nonsmooth tools (such as the Clarke, Michel-Penot
and Fréchet subdifferentials). 相似文献
995.
Natalie Priebe Frank 《Expositiones Mathematicae》2008,26(4):295-326
This paper is intended to provide an introduction to the theory of substitution tilings. For our purposes, tiling substitution rules are divided into two broad classes: geometric and combinatorial. Geometric substitution tilings include self-similar tilings such as the well-known Penrose tilings; for this class there is a substantial body of research in the literature. Combinatorial substitutions are just beginning to be examined, and some of what we present here is new. We give numerous examples, mention selected major results, discuss connections between the two classes of substitutions, include current research perspectives and questions, and provide an extensive bibliography. Although the author attempts to represent the field as a whole, the paper is not an exhaustive survey, and she apologizes for any important omissions. 相似文献
996.
In this paper we extend and generalize several known estimates for homogeneous polynomials and multilinear mappings on Banach spaces. Applying the theory of absolutely summing nonlinear mappings, we prove that estimates which are known for mappings on ?p spaces in fact hold true for mappings on arbitrary Banach spaces. 相似文献
997.
Manuel Delgado 《Journal of Differential Equations》2008,244(9):2133-2155
The main goal of this paper is the study of the existence and uniqueness of positive solutions of some nonlinear age-dependent diffusive models, arising from dynamic populations. We use a bifurcation method, for which it has been necessary to study in detail the linear and eigenvalue problems associated to the nonlinear problem in an appropriate space. 相似文献
998.
Global solution for a one-dimensional model problem in thermally radiative magnetohydrodynamics 总被引:1,自引:0,他引:1
The dynamics of gaseous stars is often described by magnetic fields coupled to self-gravitation and radiation effects. In this paper we consider an initial-boundary value problem for nonlinear planar magnetohydrodynamics (MHD) in the case that the effect of self-gravitation as well as the influence of radiation on the dynamics at high temperature regimes are taken into account. Based on the fundamental local existence results and global-in-time a priori estimates, we establish the global existence of a unique classical solution with large initial data to the initial-boundary value problem under quite general assumptions on the heat conductivity. 相似文献
999.
Laurent Thomann 《Journal of Differential Equations》2008,245(1):249-280
In this paper we consider supercritical nonlinear Schrödinger equations in an analytic Riemannian manifold (Md,g), where the metric g is analytic. Using an analytic WKB method, we are able to construct an Ansatz for the semiclassical equation for times independent of the small parameter. These approximate solutions will help to show two different types of instabilities. The first is in the energy space, and the second is an immediate loss of regularity in higher Sobolev norms. 相似文献
1000.
V. Yurko 《Journal of Differential Equations》2008,244(2):431-443
We study boundary value problems on compact graphs without circles (i.e. on trees) for second-order ordinary differential equations with nonlinear dependence on the spectral parameter. We establish properties of the spectral characteristics and investigate the inverse spectral problem of recovering the coefficients of the differential equation from the so-called Weyl vector which is a generalization of the Weyl function (m-function) for the classical Sturm-Liouville operator. For this inverse problem we prove the uniqueness theorem and obtain a procedure for constructing the solution by the method of spectral mappings. 相似文献