Results 61 to 70 of about 498 (162)
Journal of Comparative Neurology, Volume 534, Issue 5, May 2026.Honeybee mushroom bodies (MBs), sites for learning and memory, house two classes of intrinsic neurons: class I and II Kenyon cells (KCs) that form synaptic complexes with boutons of projection neurons (PNs) from primary sensory neuropils. Dendrites of both KC classes were restricted to distinct unimodal MB compartments.
Andrea Rafaela Nicolaidou +3 more
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Maximally dissipative and self‐adjoint extensions of K$K$‐invariant operators
Bulletin of the London Mathematical Society, Volume 58, Issue 5, May 2026.Abstract We introduce the notion of K$K$‐invariant operators, S$S$, in a Hilbert space, with respect to a bounded and boundedly invertible operator K$K$ defined via K∗SK=S$K^*SK=S$. Conditions such that self‐adjoint and maximally dissipative extensions of K$K$‐invariant symmetric operators are also K$K$‐invariant are investigated.
Christoph Fischbacher +2 more
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Measures of noncompactness and their applications
, 2021 The measures of noncompactness are very useful tools in the theory of operatorequations in Banach spaces. In particular, the fixed point theorems derived fromthem have many important results. In this study, we state a general information onmeasures of noncompactness and fixed point theory. In addition, applications fromvarious topics are presented.
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Results in Nonlinear Analysis, 2020 We consider the controllability problem for a class of fractional impulsive evolution systems of mixed type in an infinite dimensional Banach space. The existence of mild solutions and controllability results are discussed by a new estimation technique
Duraisamy Senthil Raja, Ponnusamy Sundararajan, Kulandhaivel Karthikeyan
doaj
Semigroups of operators and measures of noncompactness
Journal of Functional Analysis, 1971 AbstractIt is observed that the perturbation class of an open semigroup in a Banach algebra is a closed two-sided ideal. Certain seminorms on the algebra of bounded operators are introduced; these seminorms induce norms on the quotient algebra modulo the ideal of compact operators.
Lebow, Arnold, Schechter, Martin
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Electronic Journal of Qualitative Theory of Differential Equations, 2015 In this present paper, we introduce a new measure of noncompactness on the space consisting of all real functions which are $n$ times bounded and continuously differentiable on $\mathbb{R}_+$.
Reza Allahyari +2 more
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Convergence Theorems and Measures of Noncompactness for Noncompact Urysohn Operators in Ideal Spaces
Journal of Integral Equations and Applications, 2004 The author considers the following nonlinear integral equation of Urysohn type \[ A(f)x(t):= \int_S f(t, s,x(s))\,ds,\quad t\in T, \] where the integral is in the Bochner sense. He establishes an estimate for the measure of noncompactness of the Urysohn operator and proves a convergence theorem for a sequence of simpler Urysohn operators which are ...
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International Journal of Differential Equations, 2018 By combining the techniques of fractional calculus with measure of weak noncompactness and fixed point theorem, we establish the existence of weak solutions of multipoint boundary value problem for fractional integrodifferential equations.
Haide Gou, Baolin Li
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Spatial dynamics of a viral infection model with immune response and nonlinear incidence. [PDF]
Z Angew Math Phys, 2023 Zheng T, Luo Y, Teng Z.
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International Journal of Differential Equations, 2014 We consider an impulsive neutral fractional integrodifferential equation with infinite delay in an arbitrary Banach space X. The existence of mild solution is established by using solution operator and Hausdorff measure of noncompactness.
Alka Chadha, Dwijendra N. Pandey
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