0000000000124003

AUTHOR

Joan Vila

showing 9 related works from this author

Semi-Supervised Classification Method for Hyperspectral Remote Sensing Images

2004

A new approach to the classification of hyperspectral images is proposed. The main problem with supervised methods is that the learning process heavily depends on the quality of the training data set. In remote sensing, the training set is useful only for simultaneous images or for images with the same classes taken under the same conditions; and, even worse, the training set is frequently not available. On the other hand, unsupervised methods are not sensitive to the number of labelled samples since they work on the whole image. Nevertheless, relationship between clusters and classes is not ensured. In this context, we propose a combined strategy of supervised and unsupervised learning met…

Learning vector quantizationTraining setArtificial neural networkComputer sciencebusiness.industryHyperspectral imagingPattern recognitionMultispectral pattern recognitionRobustness (computer science)Unsupervised learningArtificial intelligencebusinessHyMapRemote sensing
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Urban monitoring using multi-temporal SAR and multi-spectral data

2006

In some key operational domains, the joint use of synthetic aperture radar (SAR) and multi-spectral sensors has shown to be a powerful tool for Earth observation. In this paper, we analyze the potentialities of combining interferometric SAR and multi-spectral data for urban area characterization and monitoring. This study is carried out following a standard multi-source processing chain. First, a pre-processing stage is performed taking into account the underlying physics, geometry, and statistical models for the data from each sensor. Second, two different methodologies, one for supervised and another for unsupervised approaches, are followed to obtain features that optimize the urban rela…

Synthetic aperture radarEarth observationFeature selectionStatistical modelcomputer.software_genreData setData acquisitionArtificial IntelligenceSignal ProcessingStandard algorithmsComputer Vision and Pattern RecognitionData miningcomputerSoftwareMulti-sourcePattern Recognition Letters
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Benefit of primary percutaneous coronary interventions in the elderly with ST segment elevation myocardial infarction

2020

Objective Primary percutaneous coronary intervention (P-PCI) has demonstrated its efficacy in patients with ST segment elevation myocardial infarction (STEMI). However, patients with STEMI >= 75 years receive less P-PCI than younger patients despite their higher in-hospital morbimortality. The objective of this analysis was to determine the effectiveness of P-PCI in patients with STEMI >= 75 years. Methods We included 979 patients with STEMI >= 75 years, from the ATencion HOspitalaria del Sindrome coronario study, a registry of 8142 consecutive patients with acute coronary syndrome admitted at 31 Spanish hospitals in 2014-2016. We calculated a propensity score (PS) for the indication of P-P…

MaleTime FactorsPercutaneoussistema de registrosmedicine.medical_treatmenthumanosComorbidityCoronary Artery Disease030204 cardiovascular system & hematologyLogistic regression0302 clinical medicineRecurrenceRisk Factorsevaluación de riesgosST segmentRegistries1506030212 general & internal medicineMyocardial infarctionAged 80 and overancianocoronary intervention (PCI)resultado del tratamientoCardiogenic shockAge FactorsShockstemiTreatment Outcomesurgical procedures operativeCardiologyFemaleAcute coronary syndromeCardiology and Cardiovascular MedicineStemiAcute coronary syndromemedicine.medical_specialtyShock CardiogenicPulmonary EdemaRisk Assessmentacute coronary syndromeedema pulmonar03 medical and health sciencesfactores de tiempoPercutaneous Coronary Interventionchoquecirugía coronaria percutáneaInternal medicinemedicinefactores de riesgoHumanscardiovascular diseasesAgedCoronary intervention (PCI)business.industryPercutaneous coronary interventionmedicine.diseaseSpainPropensity score matchingST Elevation Myocardial InfarctionbusinessrecurrenciaOpen Heart
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Design of a Neural Network Model as a Decision Making Aid in Renal Transplant

2004

This paper presents the application of this new tool of data processing in the study of the problem that arises when a renal transplant is indicated for a paediatric patient. Its aim is the development and validation of a neural network based model which can predict the success of the transplant over the short, medium and long term, using pre-operative characteristics of the patient (recipient) and implant organ (donor). When compared to results of logistic regression, the results of the proposed model showed better performance. Once the model is obtained, it will be converted into a tool for predicting the efficiency of the transplant protocol in order to optimise the donor-recipient pair …

Protocol (science)Artificial neural networkComputer sciencebusiness.industryRenal transplantArtificial intelligenceMachine learningcomputer.software_genrebusinessLogistic regressioncomputerPaediatric patients
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SmartSpectra: Applying multispectral imaging to industrial environments

2005

SmartSpectra is a smart multispectral system for industrial, environmental, and commercial applications where the use of spectral information beyond the visible range is needed. The SmartSpectra system provides six spectral bands in the range 400-1000nm. The bands are configurable in terms of central wavelength and bandwidth by using electronic tunable filters. SmartSpectra consists of a multispectral sensor and the software that controls the system and simplifies the acquisition process. A first prototype called Autonomous Tunable Filter System is already available. This paper describes the SmartSpectra system, demonstrates its performance in the estimation of chlorophyll in plant leaves, …

business.industryComputer scienceMultispectral imageBandwidth (signal processing)Image processingSpectral bandsFilter systemSoftwareSignal ProcessingVisible rangeComputer visionComputer Vision and Pattern RecognitionArtificial intelligenceElectrical and Electronic EngineeringbusinessComputer hardwareReal-Time Imaging
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Hypertensive status and lipoprotein oxidation in an elderly population at high cardiovascular risk.

2008

BACKGROUND: In elderly individuals, hypertension is a main risk factor for cardiovascular disease and oxidative damage is increased. Our aim was to assess the relationship between the degree of in vivo low-density lipoprotein (oxLDL) oxidation and the hypertensive status in a elderly population at high cardiovascular risk. METHODS: Cross-sectional study with baseline data from the PREDIMED (PREvención con DIeta MEDiterránea) trial, an intervention study directed at testing the efficacy of the Mediterranean diet on the primary prevention of cardiovascular disease. Participants were 1,130 subjects at high cardiovascular risk aged 55-80. At baseline, in vivo circulating oxLDL was measured, and…

MaleCoronary DiseaseDiet MediterraneanSeverity of Illness IndexRisk groupsRisk FactorsMedicineAged 80 and overCoronary diseaseBioquímica y tecnologíaIncidence0895-7061Follow up studiesAge FactorsMiddle AgedPrognosisBiochemistry and technologyHypertensionChristian ministrylipids (amino acids peptides and proteins)HipertensióFemaleHypertensive StatusLypoproteinsmedicine.medical_specialtyLipoproteinsLipid peroxidationEnzyme-Linked Immunosorbent AssayBioquímica i biotecnologiaEnvironmental healthElderly populationInternal medicineInternal MedicineHumansLipoprotein oxidationLipoprotein OxidationAgedRetrospective Studiesbusiness.industryLipoproteïnes -- OxidacióUnited StatesPersones grans -- NutricióElderly PopulationOxidative StressEndocrinologyCross-Sectional StudiesMulticenter studyOxidative stressHypertension complicationsLipid PeroxidationbusinessOlive oilFollow-Up StudiesAmerican journal of hypertension
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Protective effect of homovanillyl alcohol on cardiovascular disease and total mortality: virgin olive oil, wine, and catechol-methylathion

2016

Background: Hydroxytyrosol is a phenolic compound that is present in virgin olive oil (VOO) and wine. Hydroxytyrosol-related foods have been shown to protect against cardiovascular disease (CVD).Objective: We investigated the associations between hydroxytyrosol and its biological metabolite, 3-O-methyl-hydroxytyrosol, also known as homovanillyl alcohol (HVAL), with CVD and total mortality.Design: We included 1851 men and women with a mean ± SD age of 66.8 ± 6 y at high risk of CVD from prospective cohort data. The primary endpoint was a composite of myocardial infarction, stroke, and death from cardiovascular causes; the secondary endpoint was all-cause mortality. Twenty-four-hour urinary h…

Malemedicine.medical_specialtyGenotypeMediterranean dietCatecholsMyocardial InfarctionMedicine (miscellaneous)Wine030204 cardiovascular system & hematologyCatechol O-MethyltransferaseLower riskMethylationGastroenterology03 medical and health scienceschemistry.chemical_compound0302 clinical medicinePhenolsCause of DeathInternal medicineHomovanillyl alcoholmedicineClinical endpointHumans030212 general & internal medicineProspective cohort studyOlive OilAgedNutrition and DieteticsCatechol-O-methyl transferasebusiness.industryHomovanillic AcidMiddle AgedPhenylethyl AlcoholDietStrokechemistryCardiovascular DiseasesHydroxytyrosolFemalebusinessBiomarkersrs4680The American Journal of Clinical Nutrition
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Estimation of solar-induced vegetation fluorescence from space measurements

2007

[1] A characteristic spectral emission is observed in vegetation chlorophyll under excitation by solar radiation. This emission, known as solar-induced chlorophyll fluorescence, occurs in the red and near infra-red spectral regions. In this paper a new methodology for the estimation of solar-induced chlorophyll fluorescence from spaceborne and airborne sensors is presented. The fluorescence signal is included in an atmospheric radiative transfer scheme so that chlorophyll fluorescence and surface reflectance are retrieved consistently from the measured at-sensor radiance. This methodology is tested on images acquired by the Medium Resolution Imaging Spectrometer (MERIS) on board the ENVIron…

Materials scienceCorrelation coefficientbusiness.industryImaging spectrometerFluorescencechemistry.chemical_compoundGeophysicsOpticschemistryAbsorption bandChlorophyllRadianceRadiative transferGeneral Earth and Planetary SciencesbusinessChlorophyll fluorescenceRemote sensingGeophysical Research Letters
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Percepción de alcoholemia y capacidad de predecirla tras la ingesta de vino: actitud ante la conducción de vehículos

2014

A pesar de que la siniestralidad en carretera en España ha disminuido en los últimos años, queda un amplio margen de mejora. En este trabajo se pretende analizar la percepción de alcoholemia y la capacidad de predecirla tras medidas repetidas de la alcoholemia y la capacidad objetiva y subjetiva de conducción después de una ingesta de alcohol en el contexto de una comida. Tras una comida con ingesta libre de alcohol se procedió a la medición de la tasa de alcohol en aire espirado (AAE), preguntando antes por el nivel estimado y capacidad de conducción, después de cada medición se informaba del resultado obtenido. Participaron 34 individuos. La edad mediana fue de 56 (28-85) años. El consumo…

Sociología. Población. Trabajo socialCiencias de la salud. GeneralidadesCiencias socialesCiencias de la salud
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