0000000000280629

AUTHOR

Javier Carrasco

showing 3 related works from this author

First-principles calculations of the atomic and electronic structure ofFcenters in the bulk and on the (001) surface ofSrTiO3

2006

The atomic and electronic structure, formation energy, and the energy barriers for migration have been calculated for the neutral O vacancy point defect F center in cubic SrTiO3 employing various implementations of density functional theory DFT. Both bulk and TiO2-terminated 001 surface F centers have been considered. Supercells of different shapes containing up to 320 atoms have been employed. The limit of an isolated single oxygen vacancy in the bulk corresponds to a 270-atom supercell, in contrast to commonly used supercells containing 40– 80 atoms. Calculations carried out with the hybrid B3PW functional show that the F center level approaches the conduction band bottom to within 0.5 eV…

Materials scienceElectronic structureCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsIonCondensed Matter::Materials ScienceDelocalized electronAtomic orbitalVacancy defectIonizationPhysics::Atomic and Molecular ClustersDensity functional theoryAtomic physicsElectronic densityPhysical Review B
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Monitoring of anti-vaccine CD4 T cell frequencies in melanoma patients vaccinated with a MAGE-3 protein.

2005

Abstract Quantitative evaluation of T cell responses of patients receiving antitumoral vaccination with a protein is difficult because of the large number of possible HLA-peptide combinations that could be targeted by the response. To evaluate the responses of patients vaccinated with protein MAGE-3, we have developed an approach that involves overnight stimulation of blood T cells with autologous dendritic cells loaded with the protein, sorting by flow cytometry of the T cells that produce IFN-γ, cloning of these cells, and evaluation of the number of T cell clones that secrete IFN-γ upon stimulation with the Ag. An important criterion is that T cell clones must recognize not only stimulat…

CD4-Positive T-Lymphocytesmedicine.medical_treatmentT cellImmunologyAntigen presentationMolecular Sequence DataCD4 T cellsCell SeparationBiologyLymphocyte ActivationCancer VaccinesFlow cytometryInterleukin 21Interferon-gammaAntigenSDG 3 - Good Health and Well-beingAntigens NeoplasmMonitoring ImmunologicmedicineTumor Cells CulturedImmunology and AllergyHumansAmino Acid SequenceLymphocyte CountMelanomaCell Line TransformedAntigen Presentationmedicine.diagnostic_testT-cell receptorCoculture TechniquesGrowth InhibitorsClone CellsNeoplasm Proteinsmedicine.anatomical_structureCell cultureImmunologyAdjuvantVaccineMAGE-3 proteinJournal of immunology (Baltimore, Md. : 1950)
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First principles simulations of F centers in cubic SrTiO 3

2005

Atomic and electronic structure of regular and O-deficient SrTiO3 have been studied. Several types of first principles atomistic simulations: Hartree-Fock method, Density Functional Theory, and hybrid HF-DFT functionals, have been applied to periodic models that consider supercells of different sizes (ranging between 40 and 240 atoms). We confirm the ionic character of the Sr-O bonds and the high covalency of the Ti-O2 substructure. For the stoichiometric cubic crystal; the lattice constant and bulk modulus correctly reproduce the experimental data whereas the band gap is only properly obtained by the B3PW functional. The relaxed geometry around the F center shows a large expansion of the t…

Condensed Matter::Materials ScienceLattice constantCondensed matter physicsChemistryVacancy defectAtomPhysics::Atomic and Molecular ClustersIonic bondingDensity functional theoryElectronic structureCubic crystal systemElectronic densityphysica status solidi (c)
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