Search results for "values."

showing 10 items of 1353 documents

Veränderung des Schmeckvermögens bei Patienten mit Vestibularisschwannom

2014

Das Vestiularisschwannom ist ein gutartiger Tumor. Klinisch wird die Erkrankung durch die Kardinalsymptome einseitige Hörminderung, Tinnitus und Gleichgewichtsstörungen auffällig. Auf Grund der anatomischen Enge im Bereich des inneren Gehörganges kann es auch zu Affektionen des N.[for full text, please go to the a.m. URL]

Gynecologymedicine.medical_specialtyddc: 610Otorhinolaryngologybusiness.industryReference valuesmedicineTumor burdenIn patient610 Medical sciences; MedicinebusinessNervus facialisLaryngo-Rhino-Otologie
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Inverse eigenvalue problem for normal J-hamiltonian matrices

2015

[EN] A complex square matrix A is called J-hamiltonian if AT is hermitian where J is a normal real matrix such that J(2) = -I-n. In this paper we solve the problem of finding J-hamiltonian normal solutions for the inverse eigenvalue problem. (C) 2015 Elsevier Ltd. All rights reserved.

Hamiltonian matrixApplied MathematicsHamiltonian matrixMoore–Penrose inverseMatrius (Matemàtica)Normal matrixSquare matrixHermitian matrixCombinatoricssymbols.namesakeMatrix (mathematics)Inverse eigenvalue problemsymbolsÀlgebra linealDivide-and-conquer eigenvalue algorithmMATEMATICA APLICADAHamiltonian (quantum mechanics)Normal matrixEigenvalues and eigenvectorsMathematicsMathematical physicsApplied Mathematics Letters
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Elementary presentation of self‐consistent intermediate Hamiltonians and proposal of two totally dressed singles and doubles configuration interactio…

1994

Intermediate Hamiltonians are effective Hamiltonians which are defined on an N‐dimensional model space but which only provide n<N exact eigenvalues and the projections of the corresponding eigenvectors onto the model space. For a single root research, the intermediate Hamiltonian may be obtained from the restriction of the Hamiltonian to the model space by an appropriate, uniquely defined dressing of the diagonal energies or of the first column. Approximate self‐consistent dressings may be proposed. The simplest perturbative form gives the same result as the original 2nd order intermediate Hamiltonian or the ‘‘shifted Bk’’ technique but it is of easier implementation. Self‐consistent inclus…

HamiltoniansHamiltonians ; Configuration Interaction ; Scf Calculations ; Eigenvalues ; Eigenvectors ; Degeneration ; Many−Body Problem ; Electronic StructureDiagonalGeneral Physics and AstronomyElectronic structureMany−Body ProblemMany-body problemsymbols.namesakePauli exclusion principleQuantum mechanicsPhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]Eigenvalues and eigenvectorsMathematical physicsMathematicsDegenerate energy levelsEigenvaluesScf CalculationsConfiguration interactionUNESCO::FÍSICA::Química físicaConfiguration InteractionElectronic StructureDegenerationsymbolsEigenvectorsHamiltonian (quantum mechanics)The Journal of Chemical Physics
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A chain of solvable non-Hermitian Hamiltonians constructed by a series of metric operators

2021

We show how, given a non-Hermitian Hamiltonian $H$, we can generate new non-Hermitian operators sequentially, producing a virtually infinite chain of non-Hermitian Hamiltonians which are isospectral to $H$ and $H^\dagger$ and whose eigenvectors we can easily deduce in an almost automatic way; no ingredients are necessary other than $H$ and its eigensystem. To set off the chain and keep it running, we use, for the first time in our knowledge, a series of maps all connected to different metric operators. We show how the procedure works in several physically relevant systems. In particular, we apply our method to various versions of the Hatano-Nelson model and to some PT-symmetric Hamiltonians.

HamiltoniansQuantum PhysicsPure mathematicsSeries (mathematics)010308 nuclear & particles physicsFOS: Physical sciencesGeneral Physics and AstronomyMathematical Physics (math-ph)01 natural sciencesHermitian matrixSet (abstract data type)symbols.namesakeSimilarity mapsIsospectralChain (algebraic topology)0103 physical sciencesMetric (mathematics)symbolsQuantum Physics (quant-ph)010306 general physicsHamiltonian (quantum mechanics)Settore MAT/07 - Fisica MatematicaMathematical PhysicsEigenvalues and eigenvectorsMathematicsAnnals of Physics
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Diagnostic and prognostic values of B-type natriuretic peptides (BNP) and N-terminal fragment brain natriuretic peptides (NT-pro-BNP).

2012

Abstract B-type natriuretic peptide (BNP) is a member of a four-natriuretic peptide family that shares a common 17-peptide ring structure. The N-terminal fragment (NT-pro-BNP) is biologically inert, but both are secreted in the plasma in equimolar quantities and both have been evaluated for use in the management of congestive heart failure. BNP and NT-pro-BNP are frequently used in the diagnosis of congestive heart failure and distinguishing between patients with dyspnoea of cardiac or pulmonary origin. Values of NT-pro-BNP are affected by age or the presence of one or several co-morbidities such as chronic renal failure, type 2 diabetes, and acute coronary syndrome. ‘Normal’ values of thes…

Heart FailureAge FactorsReproducibility of ResultsComorbidityReview ArticlePrognosisSeverity of Illness IndexPeptide FragmentsDiagnosis DifferentialDyspneaPredictive Value of TestsRisk FactorsNatriuretic Peptide BrainHumansnatriuretic peptidesprognostic valueshormones hormone substitutes and hormone antagonistsBiomarkersNT-pro-BNPCardiovascular journal of Africa
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Full modal analysis of confocal coaxial elliptical waveguides

2000

An efficient method for analysing confocal coaxial elliptical waveguides is presented. Using elliptical coordinates, the differential Helmholtz equation is transformed into a linear matrix eigenvalue problem by means of the method of moments. The expressions of the vector mode functions for the full spectrum of these guides are constructed, including the TEM, TM and TE modes. The convergence of the method is very good, giving an efficient and accurate code. Comparisons with numerical results found in the technical literature validate the presented theory.

Helmholtz equationComputer Networks and Communicationsbusiness.industryModal analysisMethod of moments (statistics)Transverse modeOpticsConvergence (routing)Electrical and Electronic EngineeringCoaxialbusinessEigenvalues and eigenvectorsElliptic coordinate systemMathematicsIEE Proceedings - Microwaves, Antennas and Propagation
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Extension of the line element-less method to dynamic problems

2020

The line element-less method is an efficient approach for the approximate solution of the Laplace or biharmonic equation on a general bidimensional domain. Introducing generalized harmonic polynomials as approximation functions, we extend the line element-less method to the inhomogeneous Helmholtz equation and to the eigenvalue problem for the Helmholtz equation. The obtained approximate solutions are critically discussed and advantages as well as limitations of the approach are pointed out.

Helmholtz equationLaplace transformLine elementMechanical EngineeringHarmonic (mathematics)02 engineering and technologyLaplace equationLine element-less methodCondensed Matter Physics01 natural sciences020303 mechanical engineering & transports0203 mechanical engineeringDynamic problemMechanics of Materials0103 physical sciencesLine (geometry)Biharmonic equationApplied mathematicsHelmholtz equationSettore ICAR/08 - Scienza Delle Costruzioni010301 acousticsEigenvalues and eigenvectorsMathematics
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Monotonicity and local uniqueness for the Helmholtz equation

2017

This work extends monotonicity-based methods in inverse problems to the case of the Helmholtz (or stationary Schr\"odinger) equation $(\Delta + k^2 q) u = 0$ in a bounded domain for fixed non-resonance frequency $k>0$ and real-valued scattering coefficient function $q$. We show a monotonicity relation between the scattering coefficient $q$ and the local Neumann-Dirichlet operator that holds up to finitely many eigenvalues. Combining this with the method of localized potentials, or Runge approximation, adapted to the case where finitely many constraints are present, we derive a constructive monotonicity-based characterization of scatterers from partial boundary data. We also obtain the local…

Helmholtz equationMathematics::Number Theorylocalized potentialsBoundary (topology)Monotonic function01 natural sciencesDomain (mathematical analysis)inversio-ongelmat35R30 35J05symbols.namesakeMathematics - Analysis of PDEs35J050103 physical sciencesFOS: MathematicsUniquenessHelmholtz equation0101 mathematicsinverse coefficient problemsEigenvalues and eigenvectorsMathematicsNumerical AnalysisApplied Mathematics010102 general mathematicsMathematical analysisMathematics::Spectral Theorymonotonicitystationary Schrödinger equation35R30Helmholtz free energyBounded functionsymbols010307 mathematical physicsmonotonicity localized potentialsAnalysisAnalysis of PDEs (math.AP)
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Expression of the 60 kDa heat shock protein in normal and inflamed liver.

1993

The 60 kDa heat shock proteins (HSP 60) have been well conserved throughout evolution and are highly immunogenic. Cross-reactivity between bacterial and mammalian HSP 60 is considered a likely mechanism in the pathogenesis of autoimmune diseases. T cell and B cell reactivity to HSP 60 is found in patients with rheumatoid or juvenile arthritis, and the expression of HSP 60 in the inflamed joint is found to be increased. In this study the presence of HSP 60 was demonstrated in normal and inflamed lives. HSP 60 was found to be predominantly expressed in hepatocytes and Kupffer cells, and mainly localized in mitochondria. Heat stress in the form of a 1 h incubation at 42 degrees C increased HSP…

HepatitisHepatologyT cellKupffer cellInflammationAutoimmune hepatitisChaperonin 60Biologymedicine.diseaseMolecular biologyHepatitisPathogenesismedicine.anatomical_structureLiverReference ValuesHeat shock proteinImmunologyChronic DiseasemedicineHumansmedicine.symptomB cellHeat-Shock ProteinsJournal of hepatology
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The equality case in a Poincaré–Wirtinger type inequality

2016

It is known that, for any convex planar set W, the first non-trivial Neumann eigenvalue μ1 (Ω) of the Hermite operator is greater than or equal to 1. Under the additional assumption that Ω is contained in a strip, we show that β1 (Ω) = 1 if and only if Ω is any strip. The study of the equality case requires, among other things, an asymptotic analysis of the eigenvalues of the Hermite operator in thin domains.

Hermite operatorsymbols.namesakePure mathematicsNeumann eigenvaluesSettore MAT/05 - Analisi MatematicaHermite operator Neumann eigenvalues thin stripsGeneral MathematicsPoincaré conjecturesymbolsType inequalityThin stripsMathematicsRendiconti Lincei - Matematica e Applicazioni
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