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A Case of Recurrent Multiple Left Ventricular Thrombi without Thromboembolism in Noncompacted Myocardium
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作者 Teng Ye Shusheng Liao 《Case Reports in Clinical Medicine》 2019年第11期295-300,共6页
Background: Left ventricular noncompaction with multiple left ventricular thrombi can be revealed by echocardiography, and early diagnosis seems to be imperative to prevent significant embolic events. Case Report: A 5... Background: Left ventricular noncompaction with multiple left ventricular thrombi can be revealed by echocardiography, and early diagnosis seems to be imperative to prevent significant embolic events. Case Report: A 57-year-old woman presented with symptoms of heart failure. Two-dimensional transthoracic echocardiogram demonstrated a dilated and diffusely hypokinetic left ventricle with severe impaired left ventricular systolic function. Moreover, a markedly thickened endocardium at the left ventricular apex and middle segment with numerous, excessively prominent trabeculations and deep intertrabecular recesses were present. During systole, the ratio of the noncompacted to compacted myocardial layers at the site of the maximal wall thickness was above two, a characteristic finding in left ventricular non-compaction. Multiple mobile, homogeneous, echodense thrombi were identified in the left ventricle, with the largest one in the apical noncompacted segment (dimensions, 32 × 14 mm). Cardiac magnetic resonance imaging confirmed the diagnosis of noncompacted myocardium with the presence of multiple thrombi. After anticoagulant therapy, her symptoms improved and thrombi dissolved. Unexpectedly, she re-admitted to the cardiovascular unit with progressive dyspnea. Transthoracic echocardiogram showed new large right atrial thrombi, with the largest one was 43 × 38 mm compared to the echocardiogram done 11 months ago. The patient was anticoagulated with continuous heparin infusion for several days followed by oral Apixaban. After 4 weeks, the floating thrombi completely disappeared. After a 26-month follow-up, the patient’s condition was stable without embolic complications. Conclusion: Echocardiography was the cornerstone of diagnostic methods for early detecting left ventricular thrombi to eventually prevent embolic events. 展开更多
关键词 MULTIPLE Left VENTRICULAR THROMBI noncompacted MYOCARDIUM
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Existence of Solutions of a Convolution Integral Equation
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作者 Henry Otoo Benjamin Dadzie Mensah Lewis Brew 《Journal of Applied Mathematics and Physics》 2024年第5期1835-1847,共13页
In this study, we prove the of existence of solutions of a convolution Volterra integral equation in the space of the Lebesgue integrable function on the set of positive real numbers and with the standard norm defined... In this study, we prove the of existence of solutions of a convolution Volterra integral equation in the space of the Lebesgue integrable function on the set of positive real numbers and with the standard norm defined on it. An operator P was assigned to the convolution integral operator which was later expressed in terms of the superposition operator and the nonlinear operator. Given a ball B<sub>r</sub> belonging to the space L it was established that the operator P maps the ball into itself. The Hausdorff measure of noncompactness was then applied by first proving that given a set M∈ B r the set is bounded, closed, convex and nondecreasing. Finally, the Darbo fixed point theorem was applied on the measure obtained from the set E belonging to M. From this application, it was observed that the conditions for the Darbo fixed point theorem was satisfied. This indicated the presence of at least a fixed point for the integral equation which thereby implying the existence of solutions for the integral equation. 展开更多
关键词 VOLTERRA Integral Equation CONVOLUTION Fixed Point EXISTENCE Noncompactness
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SOME CONVERGENCE PROBLEMS REGARDING THE FRACTIONAL SCHRODINGER PROPAGATOR ON NONCOMPACT MANIFOLDS
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作者 潘亚丽 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2309-2319,共11页
Let L be the Laplace-Beltrami operator.On an n-dimensional(n≥2),complete,noncompact Riemannian manifold M,we prove that if 0<α<1,s>α/2 and f∈Hs(M),then the fractional Schr?dinger propagator e(it|L|α/2)(f... Let L be the Laplace-Beltrami operator.On an n-dimensional(n≥2),complete,noncompact Riemannian manifold M,we prove that if 0<α<1,s>α/2 and f∈Hs(M),then the fractional Schr?dinger propagator e(it|L|α/2)(f)(x)→f(x)a.e.as t→0.In addition,for when M is a Lie group,the rate of the convergence is also studied.These results are a non-trivial extension of results on Euclidean spaces and compact manifolds. 展开更多
关键词 Schrodinger propagator noncompact manifolds SPECTRA
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EXISTENCE OF SOLUTION AND APPROXIMATE CONTROLLABILITY OF A SECOND-ORDER NEUTRAL STOCHASTIC DIFFERENTIAL EQUATION WITH STATE DEPENDENT DELAY 被引量:4
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作者 Sanjukta DAS Dwijendra PANDEY N. SUKAVANAM 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1509-1523,共15页
This paper has two sections which deals with a second order stochastic neutral partial differential equation with state dependent delay. In the first section the existence and uniqueness of mild solution is obtained b... This paper has two sections which deals with a second order stochastic neutral partial differential equation with state dependent delay. In the first section the existence and uniqueness of mild solution is obtained by use of measure of non-compactness. In the second section the conditions for approximate controllability are investigated for the distributed second order neutral stochastic differential system with respect to the approximate controllability of the corresponding linear system in a Hilbert space. Our method is an extension of co-author N. Sukavanam’s novel approach in [22]. Thereby, we remove the need to assume the invertibility of a controllability operator used by authors in [5], which fails to exist in infinite dimensional spaces if the associated semigroup is compact. Our approach also removes the need to check the invertibility of the controllability Gramian operator and associated limit condition used by the authors in [20], which are practically difficult to verify and apply. An example is provided to illustrate the presented theory. 展开更多
关键词 approximate controllability cosine family state dependent delay neutral stochastic differential equation measure of noncompactness
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ON MONOTONE ITERATIVE METHOD FOR INITIAL VALUE PROBLEMS OF NONLINEAR SECOND-ORDER INTEGRO-DIFFERENTIAL EQUATIONS IN BANACH SPACES 被引量:3
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作者 陈芳启 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第5期509-518,共10页
Using the monotone iterative method and Monch Fixed point theorem, the existence of solutions and coupled minimal and maximal quasisolutions of initial value problems for mixed monotone second-order integro-differenti... Using the monotone iterative method and Monch Fixed point theorem, the existence of solutions and coupled minimal and maximal quasisolutions of initial value problems for mixed monotone second-order integro-differential equations in Banach spaces are studied. Some existence theorems of solutions and coupled minimal and maximal quasisolutions are obtained. 展开更多
关键词 integro-differential equations Kuratowski measure of noncompactness coupled lower and upper quasisolutions monotone iterative method
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THE EXISTENCE OF SOLUTIONS OF NONLINEARFREDHOLM INTEGRAL EQUATIONS IN BANACH SPACES 被引量:3
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作者 闫宝强 史国良 《Acta Mathematica Scientia》 SCIE CSCD 1998年第S1期114-119,共6页
This paper improves Tychonov ford point theorem and discusses the existence of solutions of nonlinear Fredholm integral equations on [0,+∞] in Banach spaces with Frechet space theory.
关键词 Fredholm equation Kuratowski measure of noncompactness locally equicontinuous set
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CHARACTERIZATIONS OF COMPACT OPERATORS ON SOME EULER SPACES OF DIFFERENCE SEQUENCES OF ORDER m 被引量:2
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作者 Ivana Djolovi Eberhard Malkowsky 《Acta Mathematica Scientia》 SCIE CSCD 2011年第4期1465-1474,共10页
In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ (... In the past, several authors studied spaces of m-th order difference sequences, among them, H.Polat and F.Basar ([17]) defined the Euler spaces of m-th order difference sequences e r 0 (△ ( m ) ), e r c (△ ( m ) ) and e r ∞ (△ ( m ) ) and characterized some classes of matrix transformations on them. In our paper, we add a new supplementary aspect to their research by characterizing classes of compact operators on those spaces. For that purpose, the spaces are treated as the matrix domains of a triangle in the classical sequence spaces c 0 , c and ∞ . The main tool for our characterizations is the Hausdorff measure of noncompactness. 展开更多
关键词 difference sequence spaces of order m matrix transformations compact operators Hausdorff measure of noncompactness
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STATIONARY DISTRIBUTIONS OF INFINITE PARTICLE SYSTEMS WITH NONCOMPACT STATE SPACE. 被引量:2
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作者 陈木法 《Acta Mathematica Scientia》 SCIE CSCD 1989年第1期7-19,共13页
This paper deals with the preblem of existence and uniqueness of the stationary distributions (abbr., s. d.'s) for the processes constructed in [4] .The main results are stated in § 1. For the reader's co... This paper deals with the preblem of existence and uniqueness of the stationary distributions (abbr., s. d.'s) for the processes constructed in [4] .The main results are stated in § 1. For the reader's convenience we first restate the existence theorems (Theorem 1 and 2) of the processes given in [4]. Then two existence theorems (Theorem 3 and 4) and a uniqueness theorem (Theorem 5) for the s. d.'s of the processes are presented. The last result (Theorem 6), as an application of the previous ones, is about the Schlgl model which comes from nonequilibrium statisticali physics. The details of the proofs of Theorem 3—6 are given in § 2—4. 展开更多
关键词 PRO STATIONARY DISTRIBUTIONS OF INFINITE PARTICLE SYSTEMS WITH NONCOMPACT STATE SPACE
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NONCOMPACT INFINITE OPTIMIZATION AND EQUILIBRIA OF CONSTRAINED GAMES IN GENERALIZED CONVEX SPACES 被引量:1
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作者 丁协平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第9期1002-1007,共6页
By applying a new existence theorem of quasi-equilibrium problems due to the author, some existence theorems of solutions for noncompact infinite optimization problems and noncompact constrained game problems are prov... By applying a new existence theorem of quasi-equilibrium problems due to the author, some existence theorems of solutions for noncompact infinite optimization problems and noncompact constrained game problems are proved in generalized convex spaces without linear structure. These theorems improve and generalize a number of important results in recent literature. 展开更多
关键词 noncompace infinite optimization noncompact constrained game quasiequilibrium generalized convex space
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FIXED POINT THEOREMS FOR MEIR-KEELER CONDENSING OPERATORS VIA MEASURE OF NONCOMPACTNESS 被引量:1
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作者 A.AGHAJANI M.MURSALEEN A.SHOLE HAGHIGHI 《Acta Mathematica Scientia》 SCIE CSCD 2015年第3期552-566,共15页
In this article, we introduce the notion of Meir-Keleer condensing operator in a Banach space, a characterization using L-functions and provide a few generalization of Darbo fixed point theorem. Also, we introduce the... In this article, we introduce the notion of Meir-Keleer condensing operator in a Banach space, a characterization using L-functions and provide a few generalization of Darbo fixed point theorem. Also, we introduce the concept of a bivariate Meir-Keleer condensing operator and prove some coupled fixed point theorems. As an application, we prove the existence of solutions for a large class of functional integral equations of Volterra type in two variables. 展开更多
关键词 Measure of noncompactness Darbo fixed point theorem couple fixed point Meir-Keeler condensing operator Volterra integral equation
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ON THE m^(th) ORDER DIFFERENCE SEQUENCE SPACE OF GENERALIZED WEIGHTED MEAN AND COMPACT OPERATORS 被引量:1
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作者 Metin BASARIR Emrah Evren KARA 《Acta Mathematica Scientia》 SCIE CSCD 2013年第3期797-813,共17页
In this article, using generalized weighted mean and difference matrix of order m, we introduce the paranormed sequence space l(u, v, p; △(m)), which consist of the sequences whose generalized weighted △(m)-di... In this article, using generalized weighted mean and difference matrix of order m, we introduce the paranormed sequence space l(u, v, p; △(m)), which consist of the sequences whose generalized weighted △(m)-difference means are in the linear space l(p) defined by I.J.Maddox. Also, we determine the basis of this space and compute its α-, β- and γ-duals. Further, we give the characterization of the classes of matrix mappings from l(u, v, p, △(m)) to l∞, c, and co. Finally, we apply the Hausdorff measure of noncompacness to characterize some classes of compact operators given by matrices on the space lp(U, v, △(m)) (1 ≤ p 〈 ∞). 展开更多
关键词 Paranormed sequence spaces difference sequence spaces weighted mean α- β γ-duals matrix mappings Hausdorff measure of noncompactness compactoperators
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Heat flow of harmonic maps from noncompact manifolds 被引量:1
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作者 WANG Meng LIU Xiao-feng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期431-436,共6页
The global existence of the heat flow for harmonic maps from noncompact manifolds is considered. When L^m norm of the gradient of initial data is small, the existence of a global solution is proved.
关键词 heat flow noncompact complete manifold harmonic map
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广义H—方程解的存在性及其应用
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作者 周友明 《大学数学》 1993年第3期9-13,共5页
本文讨论一类广义形式的H—方程解的存在性,推广了某些已知的结果,并用所得结果讨论了L_(p)(G)空间中的H—积分方程解的存在性。
关键词 H—equation noncompactness MEASURE BILINEAR BOUNDED OPERATOR
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ON GRAPH MEASURES IN BANACH SPACES AND DESCRIPTION OF ESSENTIAL SPECTRA OF MULTIDIMENSIONAL TRANSPORT EQUATION
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作者 Boulbeba Abdelmoumen Aref Jeribi Maher Mnif 《Acta Mathematica Scientia》 SCIE CSCD 2012年第5期2050-2064,共15页
In this paper,we define new measures called respectively graph measure of noncompactness and graph measure of weak noncompactness.Moreover,we apply the obtained results to discuss the incidence of some perturbation re... In this paper,we define new measures called respectively graph measure of noncompactness and graph measure of weak noncompactness.Moreover,we apply the obtained results to discuss the incidence of some perturbation results realized in [2] on the behavior of essential spectra of such closed densely defined linear operators on Banach spaces.These results are exploited to investigate the essential spectra of a multidimensional neutron transport operator on L1 spaces. 展开更多
关键词 measures of noncompactness and weak noncompactness in Banach spaces Fredholm operators essential spectra
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Unusual Cardiomyopathies:Some May Be More Usual Than Previously Thought and Simply Underdiagnosed
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作者 Frank W.Smart 《Cardiovascular Innovations and Applications》 2015年第B10期29-36,共8页
Heart failure is the most common cause of hospitalization in the United States.Just as the prevalence of heart failure has increased,the number of diseases identifi ed that result in the heart failure syndrome has esc... Heart failure is the most common cause of hospitalization in the United States.Just as the prevalence of heart failure has increased,the number of diseases identifi ed that result in the heart failure syndrome has escalated.Certain cardiomyopathies that have previously been regarded as very rare are being recognized with increasing frequency,because of improved imaging techniques and an increased understanding of the pathophysiologic mechanisms that result in these diseases.Improved echocardiographic techniques and methods such as spectral Doppler and 3D image rendering,along with the use of advanced diagnostic tools such as cardiac CT angiography and cardiac magnetic resonance imaging are now common.These advanced imaging methods have led to an increased appreciation of the frequency of diseases such as isolated left ventricular noncompaction and cardiac amyloidosis.Left ventricular noncompaction,once thought to occur in roughly one in one million patients,may actually be seen in fewer than one in 1000 patients.Cardiac amyloidosis,in the senile form,may exist in 80% of 80-year-old patients,although the incidence of clinical symptoms is less.As the genetic alterations that contribute to these diseases are further elucidated,improved diagnosis and a better understanding of the prognosis of these uncommon cardiomyopathies will follow. 展开更多
关键词 CARDIOMYOPATHY NONCOMPACTION cardiac AMYLOIDOSIS heart failure
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SOLUTIONS FOR SECOND ORDER IMPULSIVE INTEGRO- DIFFERENTIAL EQUATION ON UNBOUNDED DOMAINS IN BANACH SPACES
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作者 陈芳启 田瑞兰 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第6期721-729,共9页
Under loose conditions, the existence of solutions to initial value problem are studied for second order impulsive integro-differential equation with infinite moments of impulse effect on the positive half real axis i... Under loose conditions, the existence of solutions to initial value problem are studied for second order impulsive integro-differential equation with infinite moments of impulse effect on the positive half real axis in Banach spaces. By the use of recurrence method, Tonelii sequence and the locally convex topology, the new existence theorems are achieved, which improve the related results obtained by Guo Da-jun. 展开更多
关键词 impulsive integro-differential equation Tonelii sequence locally convex topology measure of noncompactness
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TWO POINTS BOUNDARY VALUE PROBLEMS IN BANACH SPACES
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作者 王志华 张凤祥 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第3期275-280,共6页
The present paper is concerned with botmdary value problem.for differential inclusions of second order in separable Banach spaces,an existence resuh is proved under weaker conditions and some existence theorems.for no... The present paper is concerned with botmdary value problem.for differential inclusions of second order in separable Banach spaces,an existence resuh is proved under weaker conditions and some existence theorems.for nonlinear second order systems can be deduced.form this paper stheorems. 展开更多
关键词 boundary value problems differential inclusions measure of noncompactness FIXED-POINT
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THE INITIAL VALUE PROBLEMS OF FIRST ORDER IMPULSIVE DIFFERENTIAL EQUATIONS IN BANACH SPACES
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作者 孙钦福 栾世霞 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第1期35-44,共10页
In this paper, by using of monotone iterative technique, the existence and iterative approximation of the minimax quasi_solutions of the initial value problems for more general first order impulsive differential equat... In this paper, by using of monotone iterative technique, the existence and iterative approximation of the minimax quasi_solutions of the initial value problems for more general first order impulsive differential equations in Banach spaces are investigated. 展开更多
关键词 Banach space first order impulsive differential measure of noncompactness minimax quasi_solution
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RELATIVE ESSENTIAL SPECTRA INVOLVING RELATIVE DEMICOMPACT UNBOUNDED LINEAR OPERATORS
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作者 Bilel KRICHEN 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期546-556,共11页
In this article, we introduce the concept of demicompactness with respect to a closed densely defined linear operator, as a generalization of the class of demicompact operator introduced by Petryshyn in [24] and we es... In this article, we introduce the concept of demicompactness with respect to a closed densely defined linear operator, as a generalization of the class of demicompact operator introduced by Petryshyn in [24] and we establish some new results in Fredholm theory. Moreover, we apply the obtained results to discuss the incidence of some perturbation results on the behavior of relative essential spectra of unbounded linear operators acting on Banach spaces. We conclude by characterizations of the relative Schechter's and approximate essential spectrum. 展开更多
关键词 Demicompact linear operator relative essential spectrum Fredholm and semi-Fredholm operators measure of noncompactness.
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EXISTENCE OF SOLUTIONS FOR NONLINEAR IMPULSIVE HAMMERSTEIN INTEGRAL EQUATIONS IN BANACH SPACES
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作者 陈芳启 陈予恕 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第2期123-132,共10页
The existence of solutions for nonlinear impulsive Hammerstein integral equations with infinite numbers of moments of impulse effect on the infinite interval R+ in Banach spaces is studied. By means of Monch fixed poi... The existence of solutions for nonlinear impulsive Hammerstein integral equations with infinite numbers of moments of impulse effect on the infinite interval R+ in Banach spaces is studied. By means of Monch fixed point theorem, an existence theorem of solutions is obtained. The result is demonstrated by means of an infinite system for impulsive integral equations. 展开更多
关键词 Hammerstein integral equation Monch fixed point theorem measure of noncompactness
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