Results 51 to 60 of about 237,939 (264)
Some remarks about the convergence of composition operators
Journal of Inequalities and ApplicationsThis article presents a new sequence of positive linear operators that results from recent advancements in the area of composition operators. We introduce the moment-generating function and utilize it to compute moments of certain orders.
Meenu Rani +2 more
doaj +1 more source
On Convexity of Composition and Multiplication Operators on Weighted Hardy Spaces
Abstract and Applied Analysis, 2009 A bounded linear operator T on a Hilbert space ℋ, satisfying ‖T2h‖2+‖h‖2≥2‖Th‖2 for every h∈ℋ, is called a convex operator. In this paper, we give necessary and sufficient conditions under which a convex composition operator on a large class of weighted ...
Karim Hedayatian, Lotfollah Karimi
doaj +1 more source
Kernels for composition of positive linear operators
Journal of Mathematical Analysis and ApplicationsThis paper investigates the composition of Bernstein--Durrmeyer operators and Szász--Mirakjan--Durrmeyer operators, focusing on the structure and properties of the associated kernel functions. In the case of the Bernstein--Durrmeyer operators, we establish new identities for the kernel arising from the composition of two and three operators, from which
Ulrich Abel +3 more
openaire +2 more sources
Revealing the structure of land plant photosystem II: the journey from negative‐stain EM to cryo‐EM
FEBS Letters, EarlyView.Advances in cryo‐EM have revealed the detailed structure of Photosystem II, a key protein complex driving photosynthesis. This review traces the journey from early low‐resolution images to high‐resolution models, highlighting how these discoveries deepen our understanding of light harvesting and energy conversion in plants.
Roman Kouřil
wiley +1 more source
Operators commuting with complex symmetric weighted composition operators on H 2
Concrete OperatorsIn this article, we initially study when an anti-linear Toeplitz operator is in the commutant of a composition operator. Primarily, we investigate weighted composition operators Wg,ψ{W}_{g,\psi } commuting with complex symmetric weighted composition ...
Bhuia Sudip Ranjan
doaj +1 more source
ITERATED COMPOSITIONS OF LINEAR OPERATIONS ON SETS OF POSITIVE UPPER DENSITY [PDF]
International Journal of Number Theory, 2009 Starting from a result of Stewart, Tijdeman and Ruzsa on iterated difference sequences, we introduce the notion of iterated compositions of linear operations. We prove a general result on the stability of such compositions (with bounded coefficients) on sets of integers having a positive upper density.
Hegyvári, Norbert +2 more
openaire +2 more sources
Reciprocal control of viral infection and phosphoinositide dynamics
FEBS Letters, EarlyView.Phosphoinositides, although scarce, regulate key cellular processes, including membrane dynamics and signaling. Viruses exploit these lipids to support their entry, replication, assembly, and egress. The central role of phosphoinositides in infection highlights phosphoinositide metabolism as a promising antiviral target.
Marie Déborah Bancilhon, Bruno Mesmin
wiley +1 more source
THE REVIEW OF ALMOST PERIODIC SOLUTIONS TO A STOCHASTIC DIERENTIAL EQUATION [PDF]
International Journal of Mathematical Modelling & Computations, 2016 This paper proves the existence and uniqueness of quadratic mean almost periodic mild so-lutions for a class of stochastic dierential equations in a real separable Hilbert space. Themain technique is based upon an appropriate composition theorem combined
Siavosh Ahmadi
doaj
Green-hyperbolic operators on globally hyperbolic spacetimes
, 2014 Green-hyperbolic operators are linear differential operators acting on sections of a vector bundle over a Lorentzian manifold which possess advanced and retarded Green's operators.
Baer, Christian
core +1 more source
Phosphatidylinositol 4‐kinase as a target of pathogens—friend or foe?
FEBS Letters, EarlyView.This graphical summary illustrates the roles of phosphatidylinositol 4‐kinases (PI4Ks). PI4Ks regulate key cellular processes and can be hijacked by pathogens, such as viruses, bacteria and parasites, to support their intracellular replication. Their dual role as essential host enzymes and pathogen cofactors makes them promising drug targets.
Ana C. Mendes +3 more
wiley +1 more source