Results 41 to 50 of about 3,332 (213)
Design and analysis strategies for robust microbiome ageing research
FEBS Letters, EarlyView.The gut microbiome changes with age and associates with age‐related morbidity and mortality, establishing it as a potential biomarker and intervention target for ageing. Realising this potential requires methodological rigour, yet distinguishing biological signals from methodological artefacts remains challenging across cohorts. This review provides an
Mark Olenik +5 more
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Oscillatory behavior of nonlinear Hilfer fractional difference equations
Advances in Difference Equations, 2021 In this paper, we study the oscillation behavior for higher order nonlinear Hilfer fractional difference equations of the type Δ a α , β y ( x ) + f 1 ( x , y ( x + α ) ) = ω ( x ) + f 2 ( x , y ( x + α ) ) , x ∈ N a + n − α , Δ a k − ( n − γ ) y ( x ) |
Tuğba Yalçın Uzun
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COMPACT DIFFERENCES OF COMPOSITION OPERATORS [PDF]
Bulletin of the Australian Mathematical Society, 2008 AbstractLet ϕ andψbe analytic self-maps of the open unit disk. Each of them induces a composition operator,CϕandCψrespectively, acting between weighted Bergman spaces of infinite order. We show that the differenceCϕ−Cψis compact if and only if both operators are compact or both operators are not compact and the pseudohyperbolic distance of the ...
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Reconstructing enzyme evolution by protein engineering
FEBS Letters, EarlyView.Natural enzyme evolution can be retraced by protein engineering methods such as directed evolution, rational design, and ancestral sequence reconstruction. These approaches reveal how enzymes emerged from ligand‐binding scaffolds, developed varying substrate preferences, formed oligomeric complexes, adapted to environmental changes, and evolved novel ...
Lukas Drexler +2 more
wiley +1 more source
Fixed Points of Difference Operator of Meromorphic Functions
The Scientific World Journal, 2014 Let f be a transcendental meromorphic function of order less than one. The authors prove that the exact difference Δf=fz+1-fz has infinitely many fixed points, if a∈ℂ and ∞ are Borel exceptional values (or Nevanlinna deficiency values) of f.
Zhaojun Wu, Hongyan Xu
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Tunneling for a Class of Difference Operators [PDF]
Annales Henri Poincaré, 2011 The authors analyze a general class of difference operators \(H_\varepsilon = T_\varepsilon + V_\varepsilon\) on \(\ell^2((\varepsilon {\mathbb{Z}})^d)\), where \(V_\varepsilon\) is a multi-well potential and \(\varepsilon\) is a small parameter. They decouple the wells by introducing certain Dirichlet operators on regions containing only one potential
Klein, Markus, Rosenberger, Elke
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Microbiome‐blood–brain barrier interactions in aging — mechanisms and therapeutic potential
FEBS Letters, EarlyView.Aging reshapes the gut microbiome (↓SCFA‐producing commensals; ↑pro‐inflammatory outputs), shifting circulating metabolites (↓SCFAs; ↑LPS, ↑TMAO, ↑PAA) that act at the BBB to increase nonspecific transcytosis, alter transport, and promote astrocyte reactivity, heightening brain vulnerability.
Daniel Cuervo‐Zanatta +3 more
wiley +1 more source
On the Spectrum of a Discrete Non-Hermitian Quantum System
Symmetry, Integrability and Geometry: Methods and Applications, 2009 In this paper, we develop spectral analysis of a discrete non-Hermitian quantum system that is a discrete counterpart of some continuous quantum systems on a complex contour.
Ebru Ergun
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On some properties of Schwartz–Gopengauz operator
Lietuvos Matematikos Rinkinys, 2023 The generalization of Schwarz’s derivative proposed by B.E. Gopengauz, which is applied to the study of the properties of the class of functions with nonvanishing in the unit circle divided difference of n-th order is examined.
Eduardas Kirjackis
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FEBS Letters, EarlyView.Animals must match their growth rate to available nutrients. We show that in Drosophila larvae, the nutrient‐sensing TOR kinase controls growth by regulating levels of TFAM, a key regulator of mitochondrial function, in the adipose tissue. When nutrients are abundant, high TOR activity suppresses TFAM, lowering mitochondrial bioenergetic activity and ...
Shrivani Sriskanthadevan‐Pirahas +4 more
wiley +1 more source