Search results for "Biomedical"

showing 10 items of 2328 documents

New biodegradable hydrogels based on an acryloylated polyaspartamide cross-linked by gamma irradiation

1999

Alpha, beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA), a synthetic biocompatible macromolecule, was functionalized with glycidyl methacrylate (GMA) in order to introduce in its side chains residues having double bonds and ester groups. The copolymer (PHG), obtained from PHEA and GMA, had a degree of derivatization of 29 mol%. PHG aqueous solutions are cross-linked by gamma radiation at 0 degrees C either in the presence or absence of N,N'-methylenebisacrylamide (BIS) giving rise to new hydrogel systems. In both cases gelation occurs at quite low doses (0.26 and 0.4 kGy, respectively). The obtained networks were characterized by FT-IR spectrophotometry which confirmed that the cross-linki…

Glycidyl methacrylateMagnetic Resonance SpectroscopyMaterials scienceBiomedical EngineeringBiophysicsBiocompatible MaterialsBioengineeringIn Vitro TechniquesBiomaterialsHydrolysischemistry.chemical_compoundEnzymatic hydrolysisMaterials TestingSpectroscopy Fourier Transform InfraredPolymer chemistryCopolymerReduced viscosityAqueous solutionHydrolysisHydrogelsBiodegradation EnvironmentalCross-Linking ReagentschemistryGamma RaysSelf-healing hydrogelsPeptidesMacromoleculeJournal of Biomaterials Science, Polymer Edition
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Biodegradable hydrogels obtained by photocrosslinking of dextran and polyaspartamide derivatives

2003

The functionalization of dextran with glycidyl methacrylate (GMA) leads to the formation of a derivative that generates hydrogels for irradiation at 365nm. The effects of various polymer concentrations and irradiation times on the yield and the properties of the obtained hydrogels are reported. The networks have been characterized by FT-IR spectra, dimensional analysis and swelling measurements carried out at different pH values. In vitro studies suggest that all samples undergo a partial chemical hydrolysis, whereas the incubation with dextranases causes a total degradation whose rate depends on the degree of crosslinking. In addition, aqueous solutions of functionalized dextran have been …

Glycidyl methacrylateMaterials scienceMagnetic Resonance SpectroscopyTime FactorsPolymersUltraviolet RaysBiophysicsBiomedical EngineeringBiocompatible MaterialsBioengineeringBiomaterialschemistry.chemical_compoundContraceptive AgentsTheophyllinePolymer chemistrySpectroscopy Fourier Transform InfraredCopolymermedicineBisphenol A-Glycidyl MethacrylateDextranPolyhydroxyethyl MethacrylatePhotocrosslinkingchemistry.chemical_classificationAqueous solutionHydrolysistechnology industry and agricultureTemperatureDextransHydrogelsPolymerDrug releaseHydrogen-Ion Concentrationαβ-Poly(N-2-hydroxyethyl)-DL-aspartamideDextranCross-Linking ReagentschemistryMechanics of MaterialsSelf-healing hydrogelsDrug deliveryCeramics and CompositesSwellingmedicine.symptomPeptidesGlycidyl methacrylateBiotechnology
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A study of reproducibility of kinesiology tape applications: review, reliability and validity

2017

Abstract Background Literature addressing the mechanical properties of kinesiology tape is quite scarce. There are no studies which focus on the mechanical characteristics of kinesiology tape, its mechanical properties, nor its adherence following the ISO international standard test methods for tape elongation. Methods This study quantified the mechanical characteristics of 380 samples of kinesiology tape from 19 different brands and in 4 different colors using a dynamometer. Mechanical testing was controlled by UNE EN ISO 13934-1. Results Significant differences were found between tape brands in terms of grammage, maximum force tenacity, work, pre-elongation and percentage elongation (P < …

GrammageMechanical processeslcsh:Diseases of the musculoskeletal systemeducationMuscle Strength DynamometerStrain03 medical and health sciences0302 clinical medicineRheumatologyHumansMedicineOrthopedics and Sports MedicineElongationReliability (statistics)030203 arthritis & rheumatology030222 orthopedicsReproducibilityDynamometerKinesiologybusiness.industryWork (physics)Mechanical ProcessesReproducibility of ResultsInjury preventionEquipment DesignProprioceptionAthletic TapeAdherenceKinesiology Appliedlcsh:RC925-935businessResearch ArticleBiomedical engineering
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Granger causality analysis of sleep brain-heart interactions

2014

We studied the networks of Granger causality (GC) between the time series of cardiac vagal autonomic activity and brain wave activities, measured respectively as the normalized high frequency (HF) component of heart rate variability and EEG power in the δ, θ, α, σ, β bands, computed in 10 healthy subjects during sleep. GC analysis was performed by vector autoregressive modeling, and significance of each link in the network was assessed using F-statistics. The whole-night analysis revealed the existence of a fully connected network of brain-heart and brain-brain interactions, with the ß EEG power acting as a hub which conveys the largest number of GC links between the heart and brain n…

Granger causality analysismedicine.diagnostic_testBiomedical EngineeringHealthy subjectsElectroencephalographySleep in non-human animalsGranger causalityAutoregressive modelSettore ING-INF/06 - Bioingegneria Elettronica E InformaticamedicineHeart rate variabilityPsychologyNeuroscienceSlow-wave sleep2014 8th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO)
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233 Diabetic care in a network of health professionals in the beaune area

2010

Objectives The GPSPB a Network of Health Professionals in the Beaune Area is a primary care network created February 2002. It covers a population of over 77,000 people and gathers together 123 health professionals. One of the health priorities of the network concerns diabetes. The aim of the study was to evaluate the overall satisfaction of patients with the diabetes care they receive and to measure the medico-economic impact of coordinated care (GPs, dieticians and podiatrists). Program To follow-up satisfaction questionnaires sent to patients with diabetes who applied to the GPSPB from April 2006 to the end of December 2007 (48 people). To study the evolution of relevant biomedical data (…

Gynecologymedicine.medical_specialtyPediatricseducation.field_of_studyHealth professionalsbusiness.industryHealth PolicyPopulationPrimary careDiabetic careNational health insuranceBiomedical dataHealth careMedicineDiabetic patientbusinesseducationBMJ Quality &amp; Safety
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Enhancement of Gene Expression by Somatic Hybridization with Primary Cells: High-Level Synthesis of the Hepatitis B Surface Antigen in Monkey Vero Ce…

1990

Vero cells transfected with the S gene encoding the surface antigen (HBsAg) of the hepatitis B virus (HBV) synthesize HBsAg at low levels. We have obtained a large increase in S gene expression by somatic hybridization of Vero cells with primary hepatocytes, which are the natural target cells for HBV infection. Fusion with cells other than hepatocytes did not enhance expression of the S gene. The Vero/hepatocyte hybrid clones analyzed are stable and have maintained a high level of HBsAg synthesis over prolonged periods. Hybrid cell lines may be of general interest for the high-level synthesis of proteins using cloned genes.

HBsAgLiver cytologyvirusesGenetic VectorsBiomedical EngineeringGene ExpressionBioengineeringHybrid CellsBiologyKidneyTransfectionmedicine.disease_causeApplied Microbiology and BiotechnologyCell LineAntigenChlorocebus aethiopsmedicineAnimalsVero CellsHepatitis B virusHepatitis B Surface AntigensCell fusionvirus diseasesTransfectionVirologyMolecular biologydigestive system diseasesLiverCell cultureVero cellRNAMolecular MedicinePapioBiotechnologyNature Biotechnology
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Reliability of automated optical determination of capillary refill time

2021

The present study is devoted to assessment of automated optical capillary refill time determination by custom developed optoelectronic device prototype. Study comprised fifteen healthy volunteers; To induce capillary refill time changes the hand position challenge was utilized. During rest conditions slight inter-subject variation was observed: T90 (0.75±0.27 s), TSTB (2.20±0.58 s) and temperature at the measurement site (32.21±1.87 Co), however during hand position challenge results were more consistent. Rising hand substantially increased, while lowering slightly decreased capillary refill time. We conclude that automated determination of refill time have high clinical potential, however …

Hand positionTime changesLight intensitymedicine.diagnostic_testComputer scienceDecreased capillary refill timeHealthy volunteersmedicineCapillary refillMeasurement siteReliability (statistics)Biomedical engineeringBiophotonics Congress 2021
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2021

Purpose: Physical activity promotes a positive physical self-image, but less is known about whether the positive effect covers the general self-evaluation of adolescent appearance. This study aimed to further explore the associations between physical activity and body-esteem in Finnish adolescents, via a country-representative cross-sectional study design. Methods: The data for the study were drawn from the Finnish component of the Health Behaviour in School-aged Children (HBSC) study (2014), using surveys from 15-year-old adolescents (n=1956, mean age 15.8 years) from 122 schools. Self-evaluations of body or appearance were measured by the Body-Esteem Scale for Adolescents and Adults (BESA…

Health (social science)PhysiologyCross-sectional studymedia_common.quotation_subjectRehabilitationBiomedical EngineeringSelf-esteemPhysical activityEthnic groupPhysical Therapy Sports Therapy and RehabilitationLinear regressionOrthopedics and Sports MedicineAnatomyAssociation (psychology)PsychologyWeight statusSocioeconomic statusDemographymedia_commonPhysical Activity and Health
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A morphology-based approach to the evaluation of atrial fibrillation organization.

2007

Health Informaticmedicine.medical_specialtybusiness.industryBiomedical EngineeringModels CardiovascularAction PotentialsAtrial fibrillationMorphology (biology)General Medicinemedicine.diseaseHealth Information ManagementBiological ClocksHeart Conduction SystemInternal medicineAtrial FibrillationmedicineCardiologySignal processing algorithmsHumansComputer SimulationHeart AtriabusinessIEEE engineering in medicine and biology magazine : the quarterly magazine of the Engineering in MedicineBiology Society
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Comparison of region of interest segmentation methods for video-based heart rate measurements

2018

International audience; Conventional contact photoplethysmography (PPG) sensors are not suitable in situations of skin damage or when unconstrained movement is required. As a consequence, remote photoplethysmography (rPPG) has recently emerged because it provides remote physiological measurements without expensive hardware and improves comfort for long-term monitoring. RPPG estimation methods use the spatially averaged RGB values of pixels in a Region Of Interest (ROI) to generate a temporal RGB signal. The selection of ROI is a critical first step to obtain reliable pulse signals and must contain as many skin pixels as possible with a low percentage of non-skin pixels. In this paper, we ex…

Heart Rate (HR)Computer science[INFO.INFO-TS] Computer Science [cs]/Signal and Image Processing0206 medical engineering02 engineering and technology01 natural sciencesSignal[INFO.INFO-CV] Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV][INFO.INFO-TS]Computer Science [cs]/Signal and Image ProcessingRegion of interestPhotoplethysmogramSegmentationComputer visionVideo basedPixelbusiness.industryremote photoplethysmography (rPPG)010401 analytical chemistryPerspective (graphical)[INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]Region of Interest (ROI)020601 biomedical engineering0104 chemical sciencesRGB color modelArtificial intelligencebusiness
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