简介：Anopen-endedcoaxiallinereflectionmethodespeciallysuitableformeas-uringthedielectricpropertiesofbiologicaltissueinvivoisdescribed.Thismethodofferstheadvantageofnotrequiringanyspecialpreparationofthesamplestobemeasuredbutaclosecontactwiththeopenendofacoaxialline.Itis,therefore,veryconvenienttoacquirealargenumberofmeasurementdatainbroadbandrapidly.Themethodmayalsobeusedtomeasurethepropertiesofothersubstances.ThemeasuringsystemconsistsofanetworkanalyzercontrolledbyamicrocomputerandcalibratedbyusingANAproceduretoelimi-hatetheinflunceoferrornetworkintroducedbytheadapter,someconnectors,etc.Inor-dertoreachhigheraccuracy,theiterativemethodisusedtodeterminetheparametersoftheequivalentcircuit.Measurementsofpermeativitiesofsomelivingtissueshavebeenper-formedinthefrequencybandof0.5-2GHz.Comparedwiththeresultsknowninsomepapers,thevalidityofthismethodhasbeenconfirmed.Thedifferenceindielectricproper-tiesbetweenlivinganddeadtissues,andthetissuepermeativites(ε)versusfrequencyanddurationofmeasurementafterdeathhavealsobeenmeasured.

简介：Purpose:Thisstudywastoinvestigatetheassociationbetweenulnarvariance(UV)andbiologicalandtrainingcharacteristics,handgrip,andwristpaininagroupof23Portugueseskeletallyimmaturemalegymnasts(aged11.22.5years).Methods:LeftandrightUVwasobtainedusingHafner'sprocedureandskeletalagewasdeterminedbytheTannereWhitehouse3-method.AnegativemeanvalueforUVmeasureswasobserved(2.4to3.6mm)withoutsignificantdifferenceswithincreasingage-category(p=0.09top=0.48).SignificantlowcorrelationswereobservedbetweensomeUVparametersandstature,fatpercentage,yearsoftraining,andlefthandgripstrength.Results:TengymnastsreportedwristpainwithgradualonsetandUVvalueswereverysimilarbetweenpainlessandpainfulwrists.Conclusion:ThefindingsofthisstudydonotdirectlysupportthethesisthatgymnasticstrainingandbiologicalvariablesorwristpainareassociatedwithUV.

简介：Background:Identifyingfactorsassociatedwithphysicalactivity(PA)isusefulinplanninginterventionsandpolicies.Theaimofthisstudywastoidentifysociodemographic,biological,andpsychosocialfactorsassociatedwithPAperformedinschoolsettings.Methods:Datacollectedforthepresentstudyincludedgender,age,socioeconomicstatus,bodyfatpercentage,aerobicfitness,self-efficacy,attitudes,peerandparentalsupport,andperceptionofschoolenvironment.Dependentvariableswerelight-intensityPA(LPA)andmoderate-to-vigorousintensityPA(MVPA)performedduringschooltime,recesses,andphysicaleducation(PE)classes.Multipleregressionanalyseswereperformed.Results:Participatingadolescents(n=567,53%female,12.9±5.3years)spent5%ofschooltimeinMVPAand27%inLPA,15%ofrecessesinMVPAand44%inLPA,and16%ofPEclassesinMVPAand41%inLPA.BoysengagedinmoreMVPAinallcategories.AgewasinverselyrelatedwithMVPAandLPAinallperiods,whereasbodyfatpercentagewasinverselyrelatedwithMVPAinschooltimeandPEclasses.AttitudewasinverselyrelatedwithMVPAinallperiodsandwithLPAinrecesses.ConsideringPAtobegoodandenjoyablewaspositivelyassociatedwithMVPAinschooltime.Conclusion:AdolescentsspentlittletimeinPAduringschool.Futureinterventionsshouldimplementenjoyableactivitiesatschool.