Search results for "numeri"

showing 10 items of 2138 documents

Factors affecting basket catheter detection of real and phantom rotors in the atria: A computational study

2018

[EN] Anatomically based procedures to ablate atrial fibrillation (AF) are often successful in terminating paroxysmal AF. However, the ability to terminate persistent AF remains disappointing. New mechanistic approaches use multiple-electrode basket catheter mapping to localize and target AF drivers in the form of rotors but significant concerns remain about their accuracy. We aimed to evaluate how electrode-endocardium distance, far-field sources and inter-electrode distance affect the accuracy of localizing rotors. Sustained rotor activation of the atria was simulated numerically and mapped using a virtual basket catheter with varying electrode densities placed at different positions withi…

Ablation TechniquesNormalization propertyTime FactorsPhysiologymedicine.medical_treatmentAction Potentials02 engineering and technology030204 cardiovascular system & hematologylaw.invention0302 clinical medicineModelslawHeart RateMedicine and Health SciencesMapping cathetersCardiac Atrialcsh:QH301-705.5Numerical AnalysisEcologyRotor (electric)HeartAblationElectrophysiologyComputational Theory and Mathematicsmedicine.veinModeling and SimulationRotorsPhysical SciencesInferior Vena CavaEngineering and TechnologyAnatomyBasket catheterArrhythmiaInterpolationResearch ArticleBiotechnologyMaterials scienceCatheters0206 medical engineeringPhase (waves)CardiologyInferior vena cavaModels BiologicalMembrane PotentialImaging phantomVeinsTECNOLOGIA ELECTRONICA03 medical and health sciencesCellular and Molecular NeuroscienceAblation Techniques; Action Potentials; Atrial Fibrillation; Computational Biology; Computer Simulation; Heart Atria; Heart Conduction System; Heart Rate; Humans; Models Biological; Time FactorsHeart Conduction SystemPhase analysisGeneticsmedicineHumansComputer SimulationHeart AtriaMolecular BiologyEcology Evolution Behavior and SystematicsMechanical EngineeringComputational BiologyBiology and Life SciencesBiological020601 biomedical engineeringAtrial fibrillationInterpolationlcsh:Biology (General)Cardiovascular AnatomyBlood VesselsMedical Devices and EquipmentMathematicsBiomedical engineeringEndocardium
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Accélération de la convergence et algorithme proximal

1995

Nous faisons une première étude de la question de savoir s'il est possible d'accélérer des suites issues de l'algorithme proximal ou de la méthode de l'inverse partiel par des méthodes d'extrapolation.

Accélération de la convergenceInverse partielMéthodes d'extrapolation[ MATH.MATH-NA ] Mathematics [math]/Numerical Analysis [math.NA][MATH.MATH-NA] Mathematics [math]/Numerical Analysis [math.NA][MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]Algorithme proximalApplication pseudo-contractante
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Numerical Methods for BVP’s Appearing in Nondestructive Ultrasonic Testing

2018

Abstract In this article we studies BVP’s that can not be solved as P.V.I or BVP with Matlab solvers ODExx or BVPxx since the solutions do not have limit in 0. We propose a numerical algorithm based on Cubic-spline written in Maple 16 [4].

AcousticsNumerical analysisUltrasonic testingGeneral MedicineBoundary value problemFixed pointMathematicsACTA Universitatis Cibiniensis
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The history of chemical enrichment in the intracluster medium from cosmological simulations

2017

The distribution of metals in the intracluster medium (ICM) of galaxy clusters provides valuable information on their formation and evolution, on the connection with the cosmic star formation and on the effects of different gas processes. By analyzing a sample of simulated galaxy clusters, we study the chemical enrichment of the ICM, its evolution, and its relation with the physical processes included in the simulation and with the thermal properties of the core. These simulations, consisting of re-simulations of 29 Lagrangian regions performed with an upgraded version of the SPH GADGET-3 code, have been run including two different sets of baryonic physics: one accounts for radiative coolin…

Active galactic nucleusCosmology and Nongalactic Astrophysics (astro-ph.CO)Radiative coolingGalaxies:clusters:general; Galaxies:clusters:Intracluster medium; Methods: numerical; Astronomy and Astrophysics; Space and Planetary ScienceMetallicityFOS: Physical sciencesclusters:Intracluster medium [Galaxies]AstrophysicsAstrophysics::Cosmology and Extragalactic Astrophysics01 natural sciencesSmoothed-particle hydrodynamicsclusters:general [Galaxies]Intracluster medium0103 physical sciencesGalaxies:clusters:Intracluster medium010303 astronomy & astrophysicsGalaxy clusterAstrophysics::Galaxy AstrophysicsPhysicsnumerical [Methods]Methods: numerical010308 nuclear & particles physicsStar formationAstronomyAstronomy and AstrophysicsAstronomy and AstrophysicAstrophysics - Astrophysics of GalaxiesGalaxies:clusters:generalSupernova13. Climate actionSpace and Planetary ScienceAstrophysics of Galaxies (astro-ph.GA)Astrophysics - Cosmology and Nongalactic Astrophysics
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Psychiatric disorders in childhood cancer survivors in Denmark, Finland, and Sweden: a register-based cohort study from the SALiCCS research programm…

2022

BACKGROUND A childhood cancer diagnosis and treatment-induced somatic late effects can affect the long-term mental health of survivors. We aimed to explore whether childhood cancer survivors are at higher risk of psychiatric disorders later in life than their siblings and the general population. METHODS In this register-based cohort study (part of the Socioeconomic Consequences in Adult Life after Childhood Cancer [SALiCCS] research programme), we included 5-year survivors of childhood cancer diagnosed before 20 years of age between Jan 1, 1974 and Dec 31, 2011, in Denmark, Finland, and Sweden. In Denmark and Sweden, 94��7% of individuals were born in a Nordic country (ie, Denmark, Finland,…

AdultHospitals PsychiatricMalemedicine.medical_specialtyAdolescentFinland/epidemiologyDenmarkPopulationPsychiatric Department HospitalCohort StudiesYoung AdultQuality of lifeCancer SurvivorsSurvivorship curveMedicinePsychiatric hospitalHumansRegistriesSiblingeducationPsychiatry610 Medicine & healthChildBiological PsychiatryFinlandSwedeneducation.field_of_studybusiness.industryMental DisordersSiblingsRegistries/statistics & numerical dataInfantMiddle AgedDenmark/epidemiologyPsychiatric Department Hospital/statistics & numerical dataPsychiatry and Mental healthSweden/epidemiologyHospitals Psychiatric/statistics & numerical dataRelative riskChild PreschoolPopulation studyFemalebusinessMental Disorders/epidemiology360 Social problems & social servicesCancer Survivors/statistics & numerical dataCohort studyThe lancet. Psychiatry
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Numbers and time doubly dissociate

2011

The magnitude dimensions of number, time and space have been suggested to share some common magnitude processing, which may imply symmetric interaction among dimensions. Here we challenge these suggestions by presenting a double dissociation between two neuropsychological patients with left (JT) and right (CB) parietal lesions and selective impairment of number and time processing respectively. Both patients showed an influence of task-irrelevant number stimuli on time but not space processing. In JT otherwise preserved time processing was severely impaired in the mere presence of task-irrelevant numbers, which themselves could not be processed accurately. In CB, impaired temporal estimatio…

AdultMaleCognitive NeuroscienceIntelligenceNumbers and timeMagnitude (mathematics)Experimental and Cognitive PsychologyNeuropsychological TestsCombinatoricsExecutive FunctionBehavioral NeuroscienceDiscrimination PsychologicalHumansAttentionTime processingProblem SolvingSize PerceptionAgedIntelligence TestsSettore M-PSI/02 - Psicobiologia E Psicologia FisiologicaParietal lobeInfarction Middle Cerebral ArteryNumerosity adaptation effectMiddle AgedMagnitude processingMagnetic Resonance ImagingData Interpretation StatisticalSpace PerceptionMental RecallTime PerceptionFemaleNumerical estimationPsychologySocial psychologyPhotic StimulationPsychomotor PerformanceNeuropsychologia
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Association Study of Nonsynonymous Single Nucleotide Polymorphisms in Schizophrenia

2010

Genome-wide association studies using several hundred thousand anonymous markers present limited statistical power. Alternatively, association studies restricted to common nonsynonymous single nucleotide polymorphisms (nsSNPs) have the advantage of strongly reducing the multiple testing problem, while increasing the probability of testing functional single nucleotide polymorphisms (SNPs).We performed a case-control association study of common nsSNPs in Galician (northwest Spain) samples using the Affymetrix GeneChip Human 20k cSNP Kit, followed by a replication study of the more promising results. After quality control procedures, the discovery sample consisted of 5100 nsSNPs at minor allel…

AdultMaleNonsynonymous substitutionGenotype"psychosis"methods [Genetic Association Studies]"mental brain homeostasis"Single-nucleotide polymorphismBiologygenetics [Cation Transport Proteins]Polymorphism Single Nucleotide03 medical and health sciences0302 clinical medicineHumansGenetic Predisposition to Diseasegenetics [Schizophrenia]ddc:610statistics & numerical data [Genetic Association Studies]genetics [Genetic Predisposition to Disease]Cation Transport ProteinsGenetic Association StudiesBiological PsychiatryAged030304 developmental biology"ZIP8"Aged 80 and overGenetics0303 health sciences"mental brain homeostasis"; "psychosis"; "metal ion transporters"; "ZIP8"; "whole-genome assosiation"; "SLC39A3"Zip8 protein humanMiddle Aged3. Good health"whole-genome assosiation"SpainCase-Control StudiesSchizophreniaFemale"SLC39A3""metal ion transporters"030217 neurology & neurosurgeryBiological Psychiatry
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Influence of articulation rate on two memory tasks in young and older adults.

2008

This study investigated the relation between phonological loop functioning and age. Phonological loop is a time-based subsystem of the Working Memory Model of Baddeley and Wilson, which uses rehearsal of information as an active process to avoid phonological decay. Performance differences were examined between young and older adults in two speech-based memory tasks, such as the immediate serial recall of words and the Digit Ordering Task. Analysis showed that performance on both tasks was lower for the older group. Articulation rate was also measured to test the hypothesis that the impairment of some cognitive functions in adults can be associated to their slowness or the greater time need…

AdultMaleRecallProcess (engineering)Age FactorsExperimental and Cognitive PsychologyCognitionMiddle AgedSensory SystemsNumerical digitTask (computing)Speech Production MeasurementMemoryMental RecallHumansSpeechFemaleBaddeley's model of working memoryArticulation (phonetics)SlownessPsychologyCognitive psychologyPerceptual and motor skills
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Modeling the impact of soft tissue on axial transmission measurements of ultrasonic guided waves in human radius

2008

Recent in vitro and simulation studies have shown that guided waves measured at low ultrasound frequencies (f=200 kHz) can characterize both material properties and geometry of the cortical bone wall. In particular, a method for an accurate cortical thickness estimation from ultrasound velocity data has been presented. The clinical application remains, however, a challenge as the impact of a layer of soft tissue on top of the bone is not yet well established, and this layer is expected to affect the dispersion and relative intensities of guided modes. The present study is focused on the theoretical modeling of the impact of an overlying soft tissue. A semianalytical method and finite-differ…

AdultMaleTime FactorsMaterials scienceAcoustics and UltrasonicsAcousticsModels BiologicalMotionYoung AdultOpticsArts and Humanities (miscellaneous)Image Interpretation Computer-AssistedmedicineHumansComputer SimulationTime domainDispersion (water waves)AgedUltrasonographyAged 80 and overGuided wave testingbusiness.industryUltrasoundBiomechanicsReproducibility of ResultsNumerical Analysis Computer-AssistedRadiusMiddle AgedRadiusmedicine.anatomical_structureConnective TissueFemaleUltrasonic sensorCortical bonebusinessThe Journal of the Acoustical Society of America
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Unconscious processing of Arabic numerals in unilateral neglect

2005

This study explores the processing of Arabic numerals in three patients with dense left unilateral neglect. Three tasks have been used: a test of visual awareness (is the stimulus on the left, on the right or on both sides?), a number comparison task (is the number larger or smaller than 5?), a number parity judgment task (is the number odd or even?). The test of visual awareness indicated that all three patients were completely unaware of the stimuli presented in the left hemifield. Despite this, the number comparison and number parity judgment tasks clearly indicated that Arabic numerals were unconsciously processed at semantic level (i.e. quantity). These results show that patients with …

AdultMaleVisual perceptionCognitive Neurosciencemedia_common.quotation_subjectExperimental and Cognitive PsychologyNeuropsychological Testsbehavioral disciplines and activitiesFunctional LateralityArabic numeralsNeglectPerceptual DisordersNumeral systemJudgmentBehavioral NeuroscienceReaction TimemedicineHumansmedia_commonNeglect Numerical processing Semantics Unconscious processingChi-Square DistributionUnconscious PsychologySettore M-PSI/02 - Psicobiologia E Psicologia FisiologicaCognitionHemispatial neglectMiddle AgedMagnetic Resonance ImagingPattern Recognition VisualUnilateral neglectAcalculiaFemalemedicine.symptomPsychologyMathematicsPhotic StimulationCognitive psychologyNeuropsychologia
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