Search results for "Linear Models"

showing 10 items of 440 documents

k-Nearest neighbour local linear prediction of scalp EEG activity during intermittent photic stimulation

2011

The characterization of the EEG response to photic stimulation (PS) is an important issue with significant clinical relevance. This study aims to quantify and map the complexity of the EEG during PS, where complexity is measured as the degree of unpredictability resulting from local linear prediction. EEG activity was recorded with eyes closed (EC) and eyes open (EO) during resting and PS at 5, 10, and 15. Hz in a group of 30 healthy subjects and in a case-report of a patient suffering from cerebral ischemia. The mean squared prediction error (MSPE) resulting from k-nearest neighbour local linear prediction was calculated in each condition as an index of EEG unpredictability. The linear or …

AdultMaleComputer sciencePhotic StimulationBiomedical EngineeringBiophysicsElectroencephalographyEyeMachine learningcomputer.software_genreBrain IschemiaYoung AdultIschemiamedicineHumansEEGPredictabilityIntermittent photic stimulationK nearest neighbourPredictability mapAgedScalpLocal linearmedicine.diagnostic_testbusiness.industrySpectrum AnalysisLocal linear predictionElectroencephalographySignal Processing Computer-AssistedPattern recognitionScalp eegmedicine.anatomical_structureScalpSettore ING-INF/06 - Bioingegneria Elettronica E InformaticaCortexLinear ModelsFemaleArtificial intelligencebusinesscomputerPhotic StimulationMedical Engineering & Physics
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Surrogate data analysis of sleep electroencephalograms reveals evidence for nonlinearity

1996

We tested the hypothesis of whether sleep electroencephalographic (EEG) signals of different time windows (164 s, 82 s, 41 s and 20.5 s) are in accordance with linear stochastic models. For this purpose we analyzed the all-night sleep electroencephalogram of a healthy subject and corresponding Gaussian-rescaled phase randomized surrogates with a battery of five non-linear measures. The following nonlinear measures were implemented: largest Lyapunov exponent L1, correlation dimension D2, and the Green-Savit measures delta 2, delta 4 and delta 6. The hypothesis of linear stochastic data was rejected with high statistical significance. L1 and D2 yielded the most pronounced effects, while the G…

AdultMaleCorrelation dimensionGeneral Computer ScienceStochastic modellingModels NeurologicalLyapunov exponentElectroencephalographysymbols.namesakeStatisticsmedicineHumansMathematicsStochastic ProcessesQuantitative Biology::Neurons and Cognitionmedicine.diagnostic_testStochastic processbusiness.industryLinear modelElectroencephalographyPattern recognitionNonlinear systemNonlinear DynamicsData Interpretation StatisticalLinear ModelssymbolsSleep (system call)Artificial intelligenceSleepbusinessCyberneticsBiotechnologyBiological Cybernetics
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Oxidative status in nondiabetic middle-aged subjects with metabolic syndrome: preliminary data.

2013

AdultMaleEndocrinology Diabetes and MetabolismMedicine (miscellaneous)PhysiologyEnzyme-Linked Immunosorbent AssayOxidative phosphorylationNitric OxideAntioxidantsProtein CarbonylationText miningMedicineHumansTriglyceridesMetabolic SyndromeNutrition and Dieteticsbusiness.industryCholesterol HDLMiddle Agedmedicine.diseaseOxidative StressLinear ModelsFemaleLipid PeroxidationMetabolic syndromeCardiology and Cardiovascular MedicinebusinessLipid peroxidation total antioxidant status insulin resistanceNutrition, metabolism, and cardiovascular diseases : NMCD
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Influence of social cognition as a mediator between cognitive reserve and psychosocial functioning in patients with first episode psychosis

2019

This work was supported by the Carlos III Institute of Health and European Fund for Regional Development (PI08/1213, PI11/01977, PI14/01900, PI08/01026, PI11/02831, PI14/01621, PI08/1161, PI16/00359, PI16/01164, PI18/00805), the Basque Foundation for Health Innovation and Research (BIOEF), the Secretaria d´Universitats I Recerca del Departament d´Economia I Coneixement (2017 SGR 1365), and R&D activities in Biomedicine, Madrid Regional Government and Structural Funds of the European Union (S2017/BMD-3740 (AGES-CM 2-CM)).

AdultMaleFirst episode psychosisAdolescentSocial perceptionPsicosiCognitive reservesocial cognitionNeuropsychological TestsPercepció socialPsychosocial functioning03 medical and health sciencesYoung Adult0302 clinical medicineMediatorSocial cognitionfirst episode psychosisHumansPath analysis (statistics)Applied PsychologyCognitive reservePsychiatric Status Rating ScalesMediation AnalysisPsychosesCognitionSocial cognition030227 psychiatryPsychiatry and Mental healthPsychotic DisordersLinear Modelspsychosocial functioningFemaleVerbal memoryCognitive reserve first episode psychosis psychosocial functioning social cognitionPsychologyNeurocognitivePsychosocial030217 neurology & neurosurgeryClinical psychology
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Causal transfer function analysis to describe closed loop interactions between cardiovascular and cardiorespiratory variability signals

2004

Although the concept of transfer function is intrinsically related to an input-output relationship, the traditional and widely used estimation method merges both feedback and feedforward interactions between the two analyzed signals. This limitation may endanger the reliability of transfer function analysis in biological systems characterized by closed loop interactions. In this study, a method for estimating the transfer function between closed loop interacting signals was proposed and validated in the field of cardiovascular and cardiorespiratory variability. The two analyzed signals x and y were described by a bivariate autoregressive model, and the causal transfer function from x to y w…

AdultMaleGeneral Computer ScienceLinear transfer functionBlood PressureBivariate analysisTransfer functionModels BiologicalFeedbackCausality (physics)Cardiovascular Physiological PhenomenaControl theoryCoherence (signal processing)HumansComputer SimulationLungMathematicsComputer Science (all)Linear modelFeed forwardReproducibility of ResultsRegression analysisHeartAutoregressive modelCardiovascular controlLinear ModelsRespiratory Physiological PhenomenaRegression AnalysisFemaleCoherenceAlgorithmsBiotechnology
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Association Between Low Education and Higher Global Cardiovascular Risk

2014

This study was designed to evaluate the impact of educational status on global cardiovascular risk in a southern Italian urban population. The study population consisted of 488 consecutive outpatients aged 18 years and older. Educational status was categorized according to the number of years of formal education as follows: (1) low education group (10 years) and (2) medium-high education group (10-15 years). In both groups, cardiometabolic comorbidities (obesity, visceral obesity, diabetes, dyslipidemia, metabolic syndrome, microalbuminuria, left ventricular hypertrophy) and global cardiovascular risk, according to international guidelines, were analyzed. Left ventricular mass index and eje…

AdultMaleGerontologyUrban PopulationLow educationCross-sectional studyEndocrinology Diabetes and MetabolismPopulationMEDLINESocioeconomic FactorRegression AnalysiBody Mass IndexWaist–hip ratioRisk FactorsCardiovascular DiseasePrevalenceInternal MedicineHumansMedicineAssociation (psychology)educationCross-Sectional Studieeducation.field_of_studyWaist-Hip Ratiobusiness.industryRisk FactorMiddle AgedEducational StatuCross-Sectional StudiesSocioeconomic FactorsItalyCardiovascular DiseasesLinear ModelsCommentaryEducational StatusRegression AnalysisLinear ModelPopulation studyFemaleCardiology and Cardiovascular MedicinebusinessBody mass indexHumanThe Journal of Clinical Hypertension
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Psychotic-like experiences in the general population of Buenos Aires city

2011

AdultMaleGerontologyeducation.field_of_studyPopulationArgentinaMEDLINECommunity health planningCommunity Health PlanningYoung AdultPsychiatry and Mental healthPsychotic DisordersLinear ModelsHumansFemaleYoung adulteducationPsychologyBiological PsychiatrySchizophrenia Research
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Impaired Health-Related Quality of Life in Inflammatory Bowel Diseases Psychosocial Impact and Coping Styles in a National German Sample

2001

The purpose of this study is to give a detailed survey of the disease-specific and generic quality of life (HRQOL) of adult patients suffering from inflammatory bowel disease (IBD) in Germany.1322 patients suffering from IBD were examined in a cross-sectional study. A questionnaire assessing disease-specific and generic quality of life, coping, and hopelessness was sent to members of the German Crohn/Colitis association.Compared to the general population, the generic HRQOL in IBD patients is significantly reduced. Active coping has a negative influence on patients' generic physical HRQOL during an active phase (beta = -0.31), while this association is not present in the case of patients in …

AdultMaleGerontologymedicine.medical_specialtyCoping (psychology)Cross-sectional studySeverity of Illness IndexInflammatory bowel diseaseAge DistributionCrohn DiseaseGermanySickness Impact ProfileSurveys and QuestionnairesAdaptation PsychologicalEpidemiologymedicineHumansSex DistributionProbabilitybusiness.industryPublic healthGastroenterologyMiddle AgedInflammatory Bowel DiseasesPrognosismedicine.diseaseHealth SurveysUlcerative colitisdigestive system diseaseshumanitiesCross-Sectional StudiesPsychological well-beingMultivariate AnalysisLinear ModelsQuality of LifeColitis UlcerativeFemalebusinessPsychosocialClinical psychologyScandinavian Journal of Gastroenterology
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Improved Nutritional Knowledge in the Obese Adult Population Modifies Eating Habits and Serum and Anthropometric Markers

2020

Multicomponent lifestyle interventions achieve good results in the management of obesity among the adult population. However, their implementation in certain populations poses difficulties. A good level of nutritional knowledge enables people to make changes in their diet that improve their health. This study aims to assess the relationship between nutritional knowledge and nutritional parameters such as dietary intake, anthropometric parameters and biomarkers. A before&ndash

AdultMaleHealth Knowledge Attitudes PracticeobesitymacronutrientsPopulation030209 endocrinology & metabolismlcsh:TX341-641OverweightArticleManagement of obesity03 medical and health sciences0302 clinical medicineWeight lossEnvironmental healthIntervention (counseling)energy expendituremedicineHumansNutritional Physiological Phenomena030212 general & internal medicineeducationeducation.field_of_studyNutrition and DieteticsattitudesAnthropometrybusiness.industryFeeding BehaviorMiddle AgedAnthropometryMicronutrientmedicine.diseaseObesityhealth knowledgeFoodmicronutrientsLinear ModelsFemalemedicine.symptombusinessdietlcsh:Nutrition. Foods and food supplyBiomarkersFood ScienceNutrients
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Differential up-regulation of circulating soluble selectins and endothelial adhesion molecules in Sicilian patients with Boutonneuse fever

1999

SUMMARYIn 150 patients with Boutonneuse fever (BF), caused by Rickettsia conorii, we studied the plasma levels of soluble l-selectin (s l-selectin), vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1) and E-selectin (sE-selectin) in various phases of disease to clarify their role in disease evolution. Results indicate that during the acute phase of BF there is a significant increase in the serum levels of s l-selectin, sE-selectin, sVCAM-1 and sICAM-1. s l-selectin and sVCAM-1 returned to normal levels in the third week of disease, whereas sE-selectin and sICAM-1 persisted at significantly high levels even after the third week. The secretion of these sol…

AdultMaleImmunologyIntercellular Adhesion Molecule-1Vascular Cell Adhesion Molecule-1BiologyBoutonneuse FeverPathogenesisLeukocyte CountmedicineHumansImmunology and AllergyL-SelectinCell adhesionAgedAnalysis of VarianceCell adhesion moleculeMiddle AgedIntercellular Adhesion Molecule-1medicine.diseasebiology.organism_classificationUp-RegulationEndothelial stem cellBoutonneuse feverSolubilityImmunologyLinear ModelsCytokinesFemaleOriginal ArticleE-SelectinRickettsia conoriiSelectinClinical and Experimental Immunology
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