Search results for " function"

showing 10 items of 9395 documents

A sharp stability estimate for tensor tomography in non-positive curvature

2021

Funder: University of Cambridge

osittaisdifferentiaaliyhtälötMathematics - Differential GeometryGeodesicGeneral Mathematics010102 general mathematicsMathematical analysisBoundary (topology)Curvature01 natural sciencesinversio-ongelmatTensor field010101 applied mathematicsmath.DGMathematics - Analysis of PDEsDifferential Geometry (math.DG)Simply connected spaceFOS: MathematicsNon-positive curvatureTensor0101 mathematicsConvex functionComputingMilieux_MISCELLANEOUSmath.APMathematicsAnalysis of PDEs (math.AP)
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Stationary sets of the mean curvature flow with a forcing term

2020

We consider the flat flow approach for the mean curvature equation with forcing in an Euclidean space $\mathbb R^n$ of dimension at least 2. Our main results states that tangential balls in $\mathbb R^n$ under any flat flow with a bounded forcing term will experience fattening, which generalizes the result by Fusco, Julin and Morini from the planar case to higher dimensions. Then, as in the planar case, we are able to characterize stationary sets in $\mathbb R^n$ for a constant forcing term as finite unions of equisized balls with mutually positive distance.

osittaisdifferentiaaliyhtälötMean curvature flowForcing (recursion theory)Mean curvatureEuclidean spaceApplied Mathematics010102 general mathematicsMathematical analysisstationary setscritical setsvariaatiolaskenta01 natural sciences35J93Term (time)010101 applied mathematicsMathematics - Analysis of PDEsFlow (mathematics)forced mean curvature flowBounded functionFOS: Mathematics0101 mathematicsConstant (mathematics)AnalysisAnalysis of PDEs (math.AP)MathematicsAdvances in Calculus of Variations
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On some partial data Calderón type problems with mixed boundary conditions

2021

In this article we consider the simultaneous recovery of bulk and boundary potentials in (degenerate) elliptic equations modelling (degenerate) conducting media with inaccessible boundaries. This connects local and nonlocal Calderón type problems. We prove two main results on these type of problems: On the one hand, we derive simultaneous bulk and boundary Runge approximation results. Building on these, we deduce uniqueness for localized bulk and boundary potentials. On the other hand, we construct a family of CGO solutions associated with the corresponding equations. These allow us to deduce uniqueness results for arbitrary bounded, not necessarily localized bulk and boundary potentials. T…

osittaisdifferentiaaliyhtälötinverse problemsApplied Mathematics(fractional) Calderón problem010102 general mathematicsDegenerate energy levelsMathematical analysisBoundary (topology)Duality (optimization)Type (model theory)partial dataCarleman estimates01 natural sciencesinversio-ongelmatrunge approximationcomplex geometrical optics solutions010101 applied mathematicsBounded functionBoundary value problemUniqueness0101 mathematicsapproksimointiAnalysisMathematicsestimointiJournal of Differential Equations
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On the second-order regularity of solutions to the parabolic p-Laplace equation

2022

AbstractIn this paper, we study the second-order Sobolev regularity of solutions to the parabolic p-Laplace equation. For any p-parabolic function u, we show that $$D(\left| Du\right| ^{\frac{p-2+s}{2}}Du)$$ D ( D u p - 2 + s 2 D u ) exists as a function and belongs to $$L^{2}_{\text {loc}}$$ L loc 2 with $$s>-1$$ s > - 1 and $$1<p<\infty $$ 1 < p < ∞ . The range of s is sharp.

osittaisdifferentiaaliyhtälötp-parabolic functionstime derivativeSobolev regularityMathematics::Analysis of PDEsfundamental inequalityWeak solutionsMathematics (miscellaneous)Fundamental inequalityweak solutionsGRADIENT111 MathematicsTime derivativeEQUIVALENCE
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Spectral multipliers and wave equation for sub-Laplacians: lower regularity bounds of Euclidean type

2018

Let $\mathscr{L}$ be a smooth second-order real differential operator in divergence form on a manifold of dimension $n$. Under a bracket-generating condition, we show that the ranges of validity of spectral multiplier estimates of Mihlin--H\"ormander type and wave propagator estimates of Miyachi--Peral type for $\mathscr{L}$ cannot be wider than the corresponding ranges for the Laplace operator on $\mathbb{R}^n$. The result applies to all sub-Laplacians on Carnot groups and more general sub-Riemannian manifolds, without restrictions on the step. The proof hinges on a Fourier integral representation for the wave propagator associated with $\mathscr{L}$ and nondegeneracy properties of the sub…

osittaisdifferentiaaliyhtälötsub-LaplacianApplied MathematicsGeneral Mathematicsharmoninen analyysi35L05 35S30 42B15 43A22 58J60Functional Analysis (math.FA)Mathematics - Functional Analysiseikonal equationMathematics - Analysis of PDEsMathematics - Classical Analysis and ODEsClassical Analysis and ODEs (math.CA)FOS: Mathematicswave equationsub-Riemannian manifoldMathematics::Differential Geometryspectral multipliermonistotFourier integral operatorAnalysis of PDEs (math.AP)Journal of the European Mathematical Society
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Otsalohkovamman vaikutus lapsen kognitiivisiin taitoihin ja käyttäytymiseen : tapaustutkimus

1998

otsalohkojen toimintahäiriötlapsen otsalohkovammaattention deficit disordertarkkaavaisuushäiriöfrontal lobe dysfunctionfrontal lobe lesion in childhoodexecutive functionstoiminnan ohjauksen vaikeudet
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Merging Features from Green's Functions and Time Dependent Density Functional Theory: A Route to the Description of Correlated Materials out of Equil…

2016

We propose a description of nonequilibrium systems via a simple protocol that combines exchange-correlation potentials from density functional theory with self-energies of many-body perturbation theory. The approach, aimed to avoid double counting of interactions, is tested against exact results in Hubbard-type systems, with respect to interaction strength, perturbation speed and inhomogeneity, and system dimensionality and size. In many regimes, we find significant improvement over adiabatic time dependent density functional theory or second Born nonequilibrium Green's function approximations. We briefly discuss the reasons for the residual discrepancies, and directions for future work.

out of equilibriumexchange-correlation potentialmany body perturbation theoryGeneral Physics and AstronomyPerturbation (astronomy)Non-equilibrium thermodynamicsFOS: Physical sciences02 engineering and technologyResidual01 natural sciencesnon-equilibrium Green's functionCondensed Matter - Strongly Correlated Electronstime dependent density functional theory0103 physical sciencesMesoscale and Nanoscale Physics (cond-mat.mes-hall)Statistical physicsnonequilibrium system010306 general physicsAdiabatic processcorrelated materialsPhysicsCondensed Matter - Materials Scienceta114Strongly Correlated Electrons (cond-mat.str-el)Condensed Matter - Mesoscale and Nanoscale PhysicsMaterials Science (cond-mat.mtrl-sci)Time-dependent density functional theory021001 nanoscience & nanotechnologyinteraction strengthperturbation techniquesFunction approximationDensity functional theory0210 nano-technologyCurse of dimensionality
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Rescue of ovarian function: stem cells and regenerative factors

2022

El envejecimiento y otras condiciones de daño adquiridas, como los tratamientos oncológicos, conducen a un deterioro de la función ovárica. Sin embargo, incluso cuando los ovarios dañados pierden su capacidad de ovular, permanece un conjunto residual de folículos quiescentes que podrían ser rescatados y desarrollados en un nicho ovárico adecuado, dando lugar a ovocitos maduros. Los factores solubles secretados por las células madre podrían proporcionar un entorno ovárico adecuado para mantener y promover el crecimiento folicular. Por lo tanto, la presente tesis doctoral tuvo como objetivo evaluar los efectos regenerativos de diferentes fuentes de factores secretados por células madre en mod…

ovarian agingstem cellsfemale infertilityUNESCO::CIENCIAS MÉDICASfertility rescuesoluble factorsimpaired ovarian function
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Estimating the safety performance function for urban unsignalized four-legged one-way intersections in Palermo, Italy

2014

Abstract Starting from consideration that urban intersections are sites with promise for safety and operational improvements, the paper describes the steps taken to develop a crash predictive model for estimating the safety performance of urban unsignalized intersections located in Palermo, Italy. The focus is on unsignalized four-legged one-way intersections widespread in Italian downtowns. The sample considered in the study consist of 92 intersections in Palermo, Italy. For the study were collected crashes occurred in the sites during the years 2006-2012, geometric design and functional characteristics and traffic flow. Results showed that data were overdispersed and NB1 distributed. In o…

overdispersionCrashSample (statistics)safety performance functionsSafety performance functions urban intersection overdispersion correlationTransport engineeringurban intersectionGeometric designGeographyOverdispersionlcsh:TA1-2040correlationSettore ICAR/04 - Strade Ferrovie Ed AeroportiPerformance functionlcsh:Engineering (General). Civil engineering (General)Generalized estimating equationCivil and Structural Engineering
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Molluscan antimicrobial peptides, a review from activity-based evidences to computer-assisted sequences

2011

Antimicrobial peptides (AMPs) represent the most universal immune effectors. Molluscs constitute the second largest animal phylum, after Arthropods, in term of number of species. Only a negligible number has been investigated regarding AMPs. The choice of the species to be studied relied on their economical importance and availability. First studies on molluscan AMPs dated from 1996 and were based on biological activities of biochemical-purified fractions. Such approach released all the original structures we know, with biological activity sometimes different from one isoform to another. Then, molecular biology techniques were applied to molluscan AMPs starting in 1999. Complete screening o…

oysterBivalvesantimicrobial peptidelcsh:Biology (General)Gastropodsmussellcsh:QH301-705.5defensinantimicrobial peptides biological function Computer-based evidencesAMPInvertebrate Survival Journal
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