Search results for "classical"

showing 10 items of 2294 documents

The relativistic mean-field model at large densities

1988

The extrapolation properties of the relativistic mean-field model are investigated in nuclear matter. The results of a recent relativistic Bethe-Brueckner-Gatdstone calculation are taken as ‘data”. Fits in a window of normal nuclear densities are extrapolated to large densities and compared with the ‘data’. We find large discrepancies which hint at an insufficiency of the model in its present parametrisation.

Nuclear physicsPhysicsNuclear and High Energy PhysicsClassical mechanicsMean field theoryNuclear TheoryExtrapolationNuclear fusionNuclear matterZeitschrift f�r Physik A Atomic Nuclei
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Plasma effects on neutrino-antineutrino synchrotron radiation in dense matter

2000

Abstract We consider plasma effects on ν ν synchroton radiation from ultrarelativistic, degenerate electrons in neutron stars with strong magnetic fields. Under typical conditions for such stars, a semiclassical calculation can be performed, in which electrons are considered to move along classical paths. We show that collective effects in the plasma lead to an essential enhancement (about three times) of the vector weak-current contributions to neutrino pair emissivity.

Nuclear physicsPhysicsNuclear and High Energy PhysicsStarsNeutron starEmissivitySemiclassical physicsSynchrotron radiationPlasmaElectronNeutrinoAtomic and Molecular Physics and OpticsNuclear Physics B - Proceedings Supplements
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Numerical approximation of the viscous quantum hydrodynamic model for semiconductors

2006

The viscous quantum hydrodynamic equations for semiconductors with constant temperature are numerically studied. The model consists of the one-dimensional Euler equations for the electron density and current density, including a quantum correction and viscous terms, coupled to the Poisson equation for the electrostatic potential. The equations can be derived formally from a Wigner-Fokker-Planck model by a moment method. Two different numerical techniques are used: a hyperbolic relaxation scheme and a central finite-difference method. By simulating a ballistic diode and a resonant tunneling diode, it is shown that numerical or physical viscosity changes significantly the behavior of the solu…

Numerical AnalysisApplied MathematicsNumerical analysisFinite difference methodResonant-tunneling diodeFinite differenceRelaxation (iterative method)Euler equationsComputational Mathematicssymbols.namesakeClassical mechanicsQuantum hydrodynamicssymbolsPoisson's equationMathematicsApplied Numerical Mathematics
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A Flux-Split Algorithm Applied to Relativistic Flows

1998

The equations of RFD can be written as a hyperbolic system of conservation laws by choosing an appropriate vector of unknowns. We give an explicit formulation of the full spectral decomposition of the Jacobian matrices associated with the fluxes in each spatial direction, which is the essential ingredient of the techniques we propose in this paper. These techniques are based on the recently derived flux formula of Marquina, a new way to compute the numerical flux at a cell interface which leads to a conservative, upwind numerical scheme. Using the spectral decompositions in a fundamental way, we construct high order versions of the basic first-order scheme described by R. Donat and A. Marqu…

Numerical AnalysisConservation lawPhysics and Astronomy (miscellaneous)Interface (Java)Applied MathematicsComputer Science ApplicationsMatrix decompositionComputational Mathematicssymbols.namesakeClassical mechanicsDimension (vector space)Modeling and SimulationScheme (mathematics)Jacobian matrix and determinantsymbolsApplied mathematicsSupersonic speedWind tunnelMathematicsJournal of Computational Physics
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Electrophoretic properties of charged colloidal suspensions: Application of a hybrid MD/LB method

2006

Abstract Electrophoretic properties of charged colloidal suspensions are investigated using a hybrid simulation method. In this method, the colloidal particles are propagated via Newton’s equations of motion using molecular dynamics (MD), while they are coupled to a structureless solvent that is modelled by the Lattice-Boltzmann (LB) method.

Numerical AnalysisMaterials scienceGeneral Computer ScienceApplied Mathematicsdigestive oral and skin physiologyEquations of motionTheoretical Computer ScienceCondensed Matter::Soft Condensed MatterSolventElectrophoresisMolecular dynamicsColloidClassical mechanicsChemical physicsColloidal particleModeling and SimulationMathematics and Computers in Simulation
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Efficient numerical method for simulating static and dynamic properties of superfluid helium

2004

Density functional theory (DFT) offers computationally affordable way of describing static and dynamic properties of superfluid 4He. In general, the DFT models yield single particle-like Schrodinger equations with a nonlinear potential term that accounts for all the many-body interactions. The resulting equations can be solved for small amplitude plane wave excitations in the bulk whereas fully numerical solution must be sought in more complicated cases. In this paper we propose a numerical method that can be used in solving the time-dependent nonlinear Schrodinger equation in both real and imaginary times. The method is based on operator splitting technique where each component operator is…

Numerical AnalysisPhysics and Astronomy (miscellaneous)Applied MathematicsNumerical analysisOperator (physics)Plane waveComputer Science ApplicationsSchrödinger equationComputational Mathematicssymbols.namesakeNonlinear systemClassical mechanicsModeling and SimulationsymbolsCrank–Nicolson methodNonlinear Schrödinger equationSuperfluid helium-4MathematicsJournal of Computational Physics
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The Right Answer for the Right Electrostatics: Force Field Methods Are Able to Describe Relative Energies of DNA Guanine Quadruplexes

2014

Different force fields and approximate density functional theory were applied in order to study the rotamer space of the telomeric G-quadruplex DNA. While some force fields show an erratic behavior when it comes to the reproduction of the higher-order DNA conformer space, OPLS and MMFF implementations are able to reproduce the experimentally known energy order. The stabilizing effect of the AA (anti−anti) versus SA (syn−anti) conformer is analyzed applying mechanical bond strength descriptors (compliance constants). The fact that we observe the correct energy order using appropriate force fields is in contrast with results previously reported, which suggested the general inappropriateness o…

OPLSMechanical bondChemistrycomputer.software_genreElectrostaticsForce field (chemistry)Computer Science Applicationschemistry.chemical_compoundClassical mechanicsSettore CHIM/03 - Chimica Generale E InorganicaDFT calculations Molecular mechanics calculations G-quadruplex DNADensity functional theoryData miningPhysical and Theoretical ChemistryGuanine-QuadruplexescomputerConformational isomerismDNAJournal of Chemical Theory and Computation
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Wild olive seed weevil in South Africa, Anchonocranus oleae Marshall (Coleoptera Curculionidae), a rediscovery after a century

2019

The wild olive seed weevil, Anchonocranus oleae Marshall, 1912 was not found after its description and the study of its biology by Silvestri in 1915. Recently, A. oleae larvae were found alive inside the kernels of wild olives (O. europaea subsp. cuspidata) collected from trees between 2009 and 2012 in the Western Cape, South Africa. No weevil larvae were found in cultivated olives collected during the same period. Only two adult weevils emerged from olives collected on the tree and on the ground. Over the sampling period 20 adults were collected directly on wild olive trees at different sites in the Western Cape and one in the Eastern Cape. All adults were shown to be conspecific with the …

Olea europaea cuspidata Western Cape Eastern Cape olive seed wasps classical biological controlSettore AGR/11 - Entomologia Generale E Applicata
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The combined role of biomarkers and interim PET scan in prediction of treatment outcome in classical Hodgkin's lymphoma: a retrospective, European, m…

2016

BACKGROUND: Early-interim fluorodeoxyglucose (FDG)-PET scan after two ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) chemotherapy courses (PET-2) represents the most effective predictor of treatment outcome in classical Hodgkin's lymphoma. We aimed to assess the predictive value of PET-2 combined with tissue biomarkers in neoplastic and microenvironmental cells for this disease.METHODS: We enrolled 208 patients with classical Hodgkin's lymphoma and treated with ABVD (training set), from Jan 1, 2002, to Dec 31, 2009, and validated the results in a fully matched independent cohort of 102 patients with classical Hodgkin's lymphoma (validation set), enrolled from Jan 1, 2008, to De…

OncologyMaleDenmarkProgrammed Cell Death 1 ReceptorCohort Studies0302 clinical medicineRecurrenceAntineoplastic Combined Chemotherapy ProtocolsTumor MicroenvironmentMedicineTreatment FailureReed-Sternberg CellsHazard ratioHematologyHodgkin DiseaseVinblastineDacarbazineSTAT1 Transcription FactorItalylymphoma PET Hodgkin030220 oncology & carcinogenesisDisease ProgressionbiomarkerFemalemedicine.drugAdultmedicine.medical_specialtyDacarbazineAntigens Differentiation MyelomonocyticSettore MED/08 - Anatomia PatologicaVinblastineDisease-Free Survival03 medical and health sciencesBleomycinAntigens CDInternal medicineHumansRetrospective StudiesFluorodeoxyglucosebusiness.industryRetrospective cohort studyPET scanmedicine.diseaseLymphomaSurgeryABVDReed–Sternberg cellDoxorubicinPositron-Emission TomographyMultivariate Analysisclassical Hodgkin's lymphoma:PolandbusinessBiomarkers030215 immunology
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Brentuximab Vedotin Plus ESHAP (BRESHAP) Versus ESHAP As Salvage Strategy for Patients with Primary Refractory or Relapsed Classical Hodgkin's Lympho…

2021

Abstract Introduction. Patients with relapsed/refractory classical Hodgkin's lymphoma (RRHL) still represent a therapeutic challenge. Consolidation with autologous stem cell transplantation (auto-HCT) is the standard of care in this setting. The achievement of a metabolic complete remission (mCR) with salvage chemotherapy (CT) improves long-term outcome after auto-HCT. The introduction of new drugs has significantly changed the landscape of RRHL. Our cooperative group (GELTAMO) has already demonstrated that brentuximab vedotin (BV) + ESHAP (BRESHAP, García-Sanz R et al, Ann Oncol 2019) is able to achieve a mCR rate of 70% before auto-HCT in patients with RRHL. Nevertheless, the superiority …

Oncologymedicine.medical_specialtybusiness.industryImmunologyCell BiologyHematologyBiochemistryClassical Hodgkin's LymphomaClinical trialRefractoryInternal medicineMedicinebusinessBrentuximab vedotinESHAPmedicine.drugBlood
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