Search results for " Impedance"

showing 10 items of 380 documents

Changes in brain natriuretic peptide levels and bioelectrical impedance measurements after treatment with high-dose furosemide and hypertonic saline …

2005

OBJECTIVES: The aim of this study was to evaluate the effect of a new treatment for refractory congestive heart failure (CHF) on brain natriuretic peptide (BNP) plasma levels and hydration station. BACKGROUND: The study was aimed at evaluating the effects of the combination of high-dose furosemide and small-volume hypertonic saline solution (HSS) in refractory CHF patients. METHODS: A total of 94 patients (34 women/60 men) with refractory CHF (age 55 to 80 years) were enrolled. They had to have an ejection fraction <35%, serum creatinine <2 mg/dl, blood urea nitrogen <60 mg/dl, a reduced urinary volume, and a low natriuresis (<500 ml/24 h and <60 mEq/24 h, respectively). Pati…

Malemedicine.medical_specialtyTime Factorsmedicine.drug_classNatriuresisDouble-Blind MethodFurosemideHeart rateNatriuretic Peptide BrainNatriuretic peptidemedicineElectric ImpedanceHumansDiureticsBlood urea nitrogenAgedAged 80 and overHeart FailureSaline Solution HypertonicEjection fractionDose-Response Relationship Drugbusiness.industryBioelectrical ImpedanceBrain Natriuretic peptideFurosemideMiddle Agedmedicine.diseaseBrain natriuretic peptideSurgeryHeart failureAnesthesiaDrug Therapy CombinationFemaleCardiology and Cardiovascular Medicinebusinessmedicine.drugFollow-Up StudiesJournal of the American College of Cardiology
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Long-Term Effects of Dietary Sodium Intake on Cytokines and Neurohormonal Activation in Patients With Recently Compensated Congestive Heart Failure

2009

Abstract Background A growing body of evidence suggests that the fluid accumulation plays a key role in the pathophysiology of heart failure (HF) and that the inflammatory and neurohormonal activation contribute strongly to the progression of this disorder. Methods and Results The study evaluated the long-term effects of 2 different sodium diets on cytokines neurohormones, body hydration and clinical outcome in compensated HF outpatients (New York Heart Association Class II). A total of 173 patients (105 males, mean age 72.5±7) recently hospitalized for worsening advanced HF and discharged in normal hydration and in clinical compensation were randomized in 2 groups (double blind). In Group …

Malemedicine.medical_specialtyTime Factorsmedicine.medical_treatmentPlasma renin activityGastroenterologychemistry.chemical_compoundDouble-Blind MethodInternal medicinemedicineHumansAgedAged 80 and overHeart FailureNeurotransmitter AgentsAldosteronebusiness.industryFurosemideSodium Dietarymedicine.diseaseBrain natriuretic peptidePathophysiologyAldosterone BNP bioelectrical impedance congestive heart failure cytochines plasma renin activatityEndocrinologyCytokinechemistryHeart failureCytokinesFemaleDiureticCardiology and Cardiovascular MedicinebusinessBiomarkersmedicine.drugFollow-Up Studies
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New insights in respiratory impedance in young children after repair of congenital diaphragmatic hernia: a cross-sectional study

2019

Abstract Lung function impairment is common in Congenital Diaphragmatic Hernia (CDH) survivors. The aim of this study was to evaluate, in children who underwent CDH surgical repair, mid and long-term consequences on respiratory impedance, investigating the impact of CDH on both resistance and reactance parameters, as well as bronchodilator response. Forced Oscillation Technique (FOT) parameters were collected from 12 patients (2–11 years). Resistance and reactance values at 8 Hz (Rrs8, Xrs8) and the area under the reactance curve (AX) were measured pre and post-salbutamol. Quantitative variables were compared using Mann-Whitney U test. Differences of categorical variables were evaluated usi…

Malemedicine.medical_specialtymedicine.drug_classCross-sectional studyCongenital diaphragmatic hernia03 medical and health sciencessymbols.namesake0302 clinical medicine030225 pediatricsBronchodilatorInternal medicinemedicineHumansAlbuterol030212 general & internal medicineChildLetter to the EditorChildrenLung functionFisher's exact testRespiratory impedancebusiness.industryAirway ResistanceSignificant differencelcsh:RJ1-570InfantCongenital diaphragmatic hernialcsh:Pediatricsmedicine.diseaseLung functionBronchodilator AgentsRespiratory Function TestsForced oscillation techniqueCross-Sectional StudiesItalyRespiratory impedanceChild PreschoolCardiologyMann–Whitney U testsymbolsFemaleHernias Diaphragmatic CongenitalbusinessChildren; Congenital diaphragmatic hernia; Forced oscillation technique; Lung function; Respiratory impedance
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Evaluation of esophageal motility and reflux in children treated for congenital diaphragmatic hernia with the use of combined multichannel intralumin…

2011

Abstract Background Gastroesophageal reflux (GER) is frequently observed in children treated for congenital diaphragmatic hernia (CDH) at birth, as well as esophageal dysmotility, that has been hypothesized to be caused by innervatory anomalies. The aim of this study is to evaluate GER and dysmotility in young patients with CDH using pH-multichannel intraluminal impedance. Methods Thirty children (17 boys and 13 girls) who underwent repair for CDH between 2002 and 2007 with a median age of 5.2 years (range, 3-10 years) were included in the study. All patients were operated on with a subcostal laparotomy incision and had a left-sided diaphragmatic defect. The defect repair required an artifi…

Malemedicine.medical_specialtymedicine.medical_treatmentMonitoring AmbulatoryCongenital diaphragmatic herniaGastroenterologyPh monitoringPostoperative ComplicationsSwallowingInternal medicineLaparotomyElectric ImpedanceHumansMedicineEsophageal Motility DisordersChildHernia Diaphragmaticbusiness.industryIncidenceEsophageal motilitySettore MED/20 - Chirurgia Pediatrica E InfantileRefluxCongenital diaphragmatic herniaGastric Acidity DeterminationGeneral MedicineHydrogen-Ion Concentrationmedicine.diseaseDeglutitionSurgeryTreatment OutcomeEsophageal motility disorderGastroesophageal refluxIntraluminal multichannel impedanceChild PreschoolAtresiaPediatrics Perinatology and Child HealthFemaleSurgeryHernias Diaphragmatic CongenitalbusinessEsophageal motility
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Body composition and changes in health-related quality of life in older age: a 10-year follow-up of the Helsinki Birth Cohort Study

2020

Abstract Purpose Most studies examining the associations between body composition and health-related quality of life (HRQoL) in older age have been cross-sectional and analyzed only fat or lean mass. Hence, it is poorly known whether fat and lean mass are independently associated with subsequent changes in HRQoL. We investigated whether baseline lean and fat mass are associated with changes in HRQoL over a 10-year period in older adults. Methods We studied 1044 men and women from the Helsinki Birth Cohort Study (age 57–70 years at baseline). Bioelectrical impedance analysis was used to derive baseline fat mass index (FMI, fat mass/height2) and lean mass index (lean mass/height2), dichotomiz…

MaleobesityAgingTime FactorsHealth-related quality of lifeelämänlaatuBody compositionCohort Studies0302 clinical medicineQuality of lifeMass index030212 general & internal medicineALL-CAUSE MORTALITYFat massConfoundingfat massMENASSOCIATIONMiddle Aged3142 Public health care science environmental and occupational healthhealth-related quality of lifeSKELETAL-MUSCLEFemaleBioelectrical impedance analysismedicine.medical_specialtyrasvakudokset030209 endocrinology & metabolismHEART-DISEASEArticle03 medical and health sciencesMASS INDEXlean massmedicineHumansObesitykehonkoostumusAgedbody compositionbusiness.industryterveydentilaDISABILITYPublic healthagingPublic Health Environmental and Occupational HealthLean massADULTSmedicine.diseaseObesity3141 Health care scienceikääntyminenCross-Sectional StudieslihasmassaStandardized coefficientLean body massQuality of LifelihavuusTRAJECTORIESbusinessDemographyFollow-Up StudiesQuality of Life Research
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Impact of Model Shape Mismatch on Reconstruction Quality in Electrical Impedance Tomography

2012

Electrical impedance tomography (EIT) is a low-cost, noninvasive and radiation free medical imaging modality for monitoring ventilation distribution in the lung. Although such information could be invaluable in preventing ventilator-induced lung injury in mechanically ventilated patients, clinical application of EIT is hindered by difficulties in interpreting the resulting images. One source of this difficulty is the frequent use of simple shapes which do not correspond to the anatomy to reconstruct EIT images. The mismatch between the true body shape and the one used for reconstruction is known to introduce errors, which to date have not been properly characterized. In the present study we…

MalereconstructionSwineComputer scienceImage processingComputed tomographyIterative reconstructionmechanical ventilationshapeLung injuryRadiationModels BiologicalArticleQuality (physics)Electrical impedance tomography (EIT)Electric ImpedanceImage Processing Computer-AssistedMedical imagingmedicineAnimalsHumansComputer visionElectrical and Electronic EngineeringLungTomographyElectrical impedance tomographymodelRadiological and Ultrasound Technologymedicine.diagnostic_testbusiness.industryMiddle AgedThoraxRespiration ArtificialComputer Science ApplicationsArtificial intelligencebusinessAlgorithmsSoftwareIEEE Transactions on Medical Imaging
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Impedance characterization of the electrochemical environment under a polymer film artificially delaminated

2008

International audience; Knowledge of the electrical conductivity of the zone under a delaminated paint film is one necessary input parameter for the simulation of electrochemically driven underpaint corrosion. In this work, a microelectrode array system has been developed, tested, and applied to measure the spatial distribution of resistivity in the delaminated zone along the metal/polymer interface. The experimental device consists of a linear array of six 100 m diameter stainless steel microelectrodes (100 m in diameter) embedded in a steel substrate. A polymer coatingwas applied and an artificial "delaminated zone"was created using the laser-induced decohesion technique. The electrochemi…

Materials science020209 energyGeneral Chemical EngineeringDelamination[ SPI.MAT ] Engineering Sciences [physics]/MaterialsOrganic coatingsImpedance02 engineering and technologyElectrolyte[SPI.MAT] Engineering Sciences [physics]/Materials021001 nanoscience & nanotechnologyDielectric spectroscopyCorrosion[SPI.MAT]Engineering Sciences [physics]/MaterialsMicroelectrodeElectrical resistivity and conductivitySteelDelaminationElectrode0202 electrical engineering electronic engineering information engineeringElectrochemistryComposite material0210 nano-technologyElectrical impedanceMicroelectrodes
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Characterization of Different Cable Ferrite Materials to Reduce the Electromagnetic Noise in the 2–150 kHz Frequency Range

2018

The gap of standardization for conducted and field coupled electromagnetic interferences (EMI) in the 2–150 kHz frequency range can lead to Electromagnetic Compatibility (EMC) problems. This is caused by power systems such as Pulse Width Modulation (PWM) controlled rectifiers, photovoltaic inverters or charging battery units in electric vehicles. This is a very important frequency spectral due to interferences generated in a wide range of devices and, specifically, communication problems in the new technologies and devices incorporated to the traditional grid to convert it into a Smart Grid. Consequently, it is necessary to provide new solutions to attenuate this kind of interference, which…

Materials scienceAcoustics02 engineering and technology01 natural scienceslcsh:TechnologyArticlelow frequency emissionsElectric power systeminsertion lossEMI0103 physical sciencescable ferriteInsertion lossGeneral Materials Sciencelcsh:MicroscopyElectrical impedancelcsh:QC120-168.85010302 applied physicscable ferrite; electromagnetic interferences; low frequency emissions; nanocrystalline; relative permeability; insertion losselectromagnetic interferenceslcsh:QH201-278.5lcsh:TPhotovoltaic systemElectromagnetic compatibilityrelative permeability021001 nanoscience & nanotechnologylcsh:TA1-2040Ferrite (magnet)lcsh:Descriptive and experimental mechanicsnanocrystallinelcsh:Electrical engineering. Electronics. Nuclear engineering0210 nano-technologylcsh:Engineering (General). Civil engineering (General)lcsh:TK1-9971Pulse-width modulationMaterials; Volume 11; Issue 2; Pages: 174
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Electromechanical Impedance Method to Assess the Stability of Dental Implants

2017

In this paper we illustrate the application of the electromechanical impedance (EMI) technique, popular in structural health monitoring, to assess the stability of dental implants. The technique consists of bonding a piezoelectric transducer to the element to be monitored. When subjected to an electric field, the transducer induces low to high frequency structural excitations which, in turn, affect the transducer's electrical admittance. As the structural vibrations depend on the mechanical impedance of the host structure (in this case the implant secured to the jaw), the measurement of the PZT's admittance can infer the progress of the osseointegration process. In the study presented in th…

Materials scienceAdmittanceAcousticsmedicine.medical_treatmentMechanical impedanceOsseointegrationFinite element methodTransducerEMI methodFEM analysis.medicineDental Implant stabilityStructural health monitoringSettore ICAR/08 - Scienza Delle CostruzioniDental implantAbutment (dentistry)Structural Health Monitoring 2017
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Study the effects of moisture content on the electrical properties of technical textiles by impedance spectroscopy

2012

Application of metal coatings for the functionalization of technical fibres and fabrics faced with influence of moisture on functional properties, e.g., the impedance of the metal coated K-glass fabrics have strong dependence of content absorbed water or moisture. The paper devoted to develop methodology for characterisation functional materials based on fabrics and model for interpretation of the electrical impedance spectra to obtained functional characteristics of technical textile fabrics. Model based on analyses of 3D plot of imaginary part of complex modulus spectra versus sample mass. Methodology helps to control content of adsorbed water in fabric and influence of moisture on the fu…

Materials scienceAdsorptionMoistureModulusSurface modificationComposite materialTechnical textileElectrical impedanceWater contentDielectric spectroscopyIOP Conference Series: Materials Science and Engineering
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