简介:Systemictoxicityandinsufficientdrugaccumulationatthetumours让earemainbarriersinchemotherapy.Thermosens让iveliposomes(TSL)combinedwithhighintensityfocusedultrasound(HIFU)hasemergedasapotentialsolutiontoovercomethesebarriersthroughtargeteddrugdeliveryandlocalisedrelease.Owingtothemultiplephysicalandbiochemicalprocessesinvolvedinthiscombinationtherapy,mathematicalmodellingbecomesanindispensabletoolfordetailedanalysisofthetransportprocessesandpredictionoftumourdruguptake.Tothisend,amultiphysicsmodelhasbeendevelopedtosimulatethetransportofchemotherapydrugsdeliveredthroughacombinedHIFU-TSLsystem.Allkeydeliveryprocessesareconsideredinthemodel;theseineludeinterstitialfluidflow,HIFUacoustics,bioheattransfer;drugreleaseandtransport,aswellastumourdruguptake.Thecapabilityofthemodelisdemonstratedthroughitsapplicationtoa2-Dprostatetumourmodelreconstructedfrommagneticresonanceimages.Ourresultsnotonlydemonstratethefeasibilityofthemodeltosimulatethiscombinationtherapy,butalsoconfirmtheadvantageofHIFU-TSLdrugdeliverysystemwithenhancementofdrugaccumulationintumourregionsandreductionofdrugavailabilityinnormaltissue.ThismultiphysicsmodellingframeworkcanserveasausefultooltoassistinthedesignofHIFU-TSLdrugdeliverysystemsandtreatmentregimenforimprovedanticancerefficacy.
简介:Earthquakeengineershavemadealotofeffortstoderiveacomprehensivesetofclosedformexpressionsforperformanceevaluationofframes,whicharealreadypresentedinguidelinessuchasSAC/FEMA.Theseanalyticalexpressionshavebeendevelopedtoestimatetheannualprobabilityofexceedingalimitstate.Intheprocessofsuchseismicassessments,someessentialassumptionsareadoptedtosimplifytheprocess.Oneofthesefundamentalassumptionsdeclaresthatdriftdemandatanyseismicintensitylevelfollowsalognormaldistributionarounditsmedian.Toinvestigatethevalidityofthisassumption,thispaperdescribesacasestudyofthetypesoferrorsthatcouldbeproducedbyusingthesamplemedianasthecentraltendency.BasedontheMaximumLikelihoodEstimationmethodaswellasotherstatisticalevidence,thispaperproposestheuseofthesamplegeometricmeaninsteadofthesamplemedianforthecentraltendency.Further,theresultsofseismicreliabilityevaluationsof4sampleframesarecomparedbasedonutilizingboththegeometricmeanandthesamplemedian.Inthisprocess,bothfirstandsecondorderpowerlawfitsofthehazardcurveareimplementedtocomparetheeffectsofhazardestimationandtheselectionofthecentraltendencyonthefinalresults.Itisobservedintheapplicationexamplethatthesamplegeometricmeancouldleadtomoreaccurateresults.