Results 101 to 110 of about 850,915 (318)
Essential norm of substitution operators on L p spaces
Indian Journal of Pure and Applied Mathematics, 2012 Let \((X,\Sigma, \mu)\) be a \(\sigma\)-finite measure space. Suppose that \(\varphi:X \to X\) is a non-singular transformation, that is, \(\mu\circ \varphi^{-1} \ll \mu\), and let \(u\) be a \(\Sigma\)-measurable function on \(X\). By the Radon-Nikodým theorem, for every \(f\in L^1\) there exists a \(\mu\)-unique function \(\tilde{f}_{\varphi}^{u}\in ...
Jabbarzadeh, M. R., Estaremi, Y.
openaire +2 more sources
On the Essential Norm of Multiplications Operators Acting on Cesàro Sequence Spaces
Journal of Function Spaces, 2019 In this article, we establish an important property about the growth of sequences in the dual space of Cesàro sequence spaces. As a consequence of this fact, we calculate the measure of noncompactness or the essential norm of the multiplication operator ...
Julio C. Ramos-Fernández +2 more
doaj +1 more source
Molecular bases of circadian magnesium rhythms across eukaryotes
FEBS Letters, EarlyView.Circadian rhythms in intracellular [Mg2+] exist across eukaryotic kingdoms. Central roles for Mg2+ in metabolism suggest that Mg2+ rhythms could regulate daily cellular energy and metabolism. In this Perspective paper, we propose that ancestral prokaryotic transport proteins could be responsible for mediating Mg2+ rhythms and posit a feedback model ...
Helen K. Feord, Gerben van Ooijen
wiley +1 more source
The essential norm of a composition operator mapping into Qk type spaces
Journal of Function Spaces and Applications, 2008 An asymptotic formula for the essential norm of the composition operator Cφ(f):=f∘φ, induced by an analytic self-map φ of the unit disc, mapping from the α-Bloch space ℬα or the Dirichlet type space Dαp into Qk(p,q) is established in terms of an integral
Marko Kotilainen, Jouni Rättyä
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FEBS Letters, EarlyView.This perspective highlights emerging insights into how the circadian transcription factor CLOCK:BMAL1 regulates chromatin architecture, cooperates with other transcription factors, and coordinates enhancer dynamics. We propose an updated framework for how circadian transcription factors operate within dynamic and multifactorial chromatin landscapes ...
Xinyu Y. Nie, Jerome S. Menet
wiley +1 more source
Real‐time assay of ribonucleotide reductase activity with a fluorescent RNA aptamer
FEBS Letters, EarlyView.Ribonucleotide reductases (RNR) synthesize DNA building blocks de novo, making them crucial in DNA replication and drug targeting. FLARE introduces the first single‐tube real‐time coupled RNR assay, which enables isothermal tracking of RNR activity at nanomolar enzyme levels and allows the reconstruction of allosteric regulatory patterns and rapid ...
Jacopo De Capitani +4 more
wiley +1 more source
Disordered but rhythmic—the role of intrinsic protein disorder in eukaryotic circadian timing
FEBS Letters, EarlyView.Unstructured domains known as intrinsically disordered regions (IDRs) are present in nearly every part of the eukaryotic core circadian oscillator. IDRs enable many diverse inter‐ and intramolecular interactions that support clock function. IDR conformations are highly tunable by post‐translational modifications and environmental conditions, which ...
Emery T. Usher, Jacqueline F. Pelham
wiley +1 more source
Journal of Function Spaces, 2018 We compute upper and lower bounds for essential norm of difference of composition operators acting from weighted Bergman spaces to Bloch-type spaces.
Ram Krishan +2 more
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Time after time – circadian clocks through the lens of oscillator theory
FEBS Letters, EarlyView.Oscillator theory bridges physics and circadian biology. Damped oscillators require external drivers, while limit cycles emerge from delayed feedback and nonlinearities. Coupling enables tissue‐level coherence, and entrainment aligns internal clocks with environmental cues.
Marta del Olmo +2 more
wiley +1 more source