Search results for "Variable"

showing 10 items of 1674 documents

A PDE model for the spatial dynamics of a voles population structured in age

2020

Abstract We prove existence and stability of entropy weak solutions for a macroscopic PDE model for the spatial dynamics of a population of voles structured in age. The model consists of a scalar PDE depending on time, t , age, a , and space x = ( x 1 , x 2 ) , supplemented with a non-local boundary condition at a = 0 . The flux is linear with constant coefficient in the age direction but contains a non-local term in the space directions. Also, the equation contains a term of second order in the space variables only. Existence of solutions is established by compensated compactness, see Panov (2009), and we prove stability by a doubling of variables type argument.

Parabolic–hyperbolic equationEnergy estimateseducation.field_of_studyConstant coefficientsDoubling of variablesPopulation dynamics structured in age and spaceApplied Mathematics010102 general mathematicsPopulationMathematical analysis01 natural sciences010101 applied mathematicsCompact spaceNon-local fluxCompensated compactnessPopulation dynamics structured in age and space Parabolic–hyperbolic equation Non-local flux Boundary value problem Energy estimates Compensated compactness Doubling of variablesBoundary value problem0101 mathematicseducationBoundary value problemAnalysisMathematics
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Detachment From Parents, Problem Behaviors, and the Moderating Role of Parental Support Among Italian Adolescents

2012

This study examined the relationship of emotional detachment from parents, parental support, and problem behaviors and focused on the unique and common contribution that detachment and parental support made to internalizing and externalizing behavioral problems. A total of 461 young adolescents, 13 to 14 years old ( M = 13.4; SD = 0.44), 234 boys and 227 girls, completed self-reporting measures of detachment, parental support, and internalizing and externalizing problems. Data showed that detachment was related positively to internalizing problem behaviors. Results revealed that parental support played a moderating role in the relationship between detachment and internalizing problems, suc…

Parental supporteducationPredictor variablesEmotional detachmentYoung adolescentsDevelopmental psychologySettore M-PSI/04 - Psicologia Dello Sviluppo E Psicologia Dell'EducazioneParenting stylesmedicineEarly adolescentsadolescents detachment behavioral problems parental support parent/child relationsmedicine.symptomPsychologySocial Sciences (miscellaneous)Journal of Family Issues
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Existence and uniqueness for the Prandtl equations

2001

International audience; Under the hypothesis of analyticity of the data with respect to the tangential variable we prove the existence and uniqueness of the mild solution of Prandtl boundary layer equation. This can be considered an improvement of the results of [8] as we do not require analyticity with respect to the normal variable. (C) 2001 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.

Partial differential equation010102 general mathematicsPrandtl numberMathematical analysisGeneral Medicine01 natural sciencesEuler equations010101 applied mathematicssymbols.namesakeBoundary layer[MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph]symbolsUniqueness0101 mathematicsConvection–diffusion equationNavier–Stokes equationsVariable (mathematics)Mathematics
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Search for Higgs bosons decaying to WW in e(+)e(-) stope collisions at LEP

2006

A search for Higgs bosons produced in association with a fermion pair, and decaying to WW, is performed with the data collected by the ALEPH detector at centre-of-mass energies ranging from 191 to 209 GeV. The data correspond to an integrated luminosity of 453.2 pb^-1. Thirteen exclusive selections are developed according to the different final state topologies. No statistically significant evidence for a Higgs boson decaying into a WW pair has been found. An upper limit is derived, as a function of the Higgs boson mass, on the product of the e+e- -> Hff cross section and the H -> WW branching ratio. The data on the search for H -> WW are combined with previously published ALEPH re…

Particle physicsAlephPhysics and Astronomy (miscellaneous)Electron–positron annihilationFOS: Physical sciences7. Clean energy01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsEngineering (miscellaneous)BosonPhysicsLuminosity (scattering theory)010308 nuclear & particles physicsBranching fractionHigh Energy Physics::PhenomenologyFermionFunction (mathematics)3. Good healthHiggs bosonHigh Energy Physics::ExperimentHiggs Boson Invariant Mass Higgs Boson Mass Time Projection Chamber Inant VariableParticle Physics - Experiment
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Inclusive B-meson production at small p_T in the general-mass variable-flavor-number scheme

2015

We calculate the cross section for the inclusive production of B mesons in pp and ppbar collisions at next-to-leading order in the general-mass variable-flavor-number scheme and show that a suitable choice of factorization scales leads to a smooth transition to the fixed-flavor-number scheme. Our numerical results are in good agreement with data from the Tevatron and LHC experiments at small and at large transverse momenta.

Particle physicsPhysics and Astronomy (miscellaneous)TevatronFOS: Physical scienceslow [transverse momentum]01 natural sciencesCross section (physics)High Energy Physics - Phenomenology (hep-ph)Factorization0103 physical sciencesscattering [p p]Order (group theory)B mesonddc:530Batavia TEVATRON Collinclusive production [B]factorization [scale]010306 general physicsnumerical calculationsNuclear ExperimentEngineering (miscellaneous)Variable (mathematics)PhysicsLarge Hadron Colliderscattering [anti-p p]higher-order [correction]010308 nuclear & particles physicsHigh Energy Physics::Phenomenologycalculated [total cross section]Transverse planeHigh Energy Physics - PhenomenologyCERN LHC Coll[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]High Energy Physics::Experiment1 [higher-order]correction [total cross section]
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Symptoms of Depression and Status in the European Labour Market

2017

This study uses three rounds of European Social Survey to study the effects from the status in the labour market of individuals from general population on the strength of their depression symptoms. Particular interest is in the comparison of the mismatched (over- and undereducated) to other kinds of status. Mismatch is defined by a normative (ISCO-based) measure. The main result is that not only overeducation but also (though to a smaller extent) undereducation is associated with an increased presence of depression symptoms. Health, income, personality, religion, the frequency of watching news on TV and partner’s status in the labour market are among the independent variables.

Partner effectseducation.field_of_studyVariablesActuarial sciencemedia_common.quotation_subjectPopulationEuropean Social SurveyDepression (economics)NormativePersonalityDemographic economicsPsychologyeducationmedia_common
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V-Belt Winding along Archimedean Spirals During the Variator Speed Ratio Shift

2010

Starting from a previous model for the shift mechanics of rubber belt variators, this lecture elaborates practical design formulas for the torque and the axial thrust making use of the very close resemblance of the belt path to a linear spiral of Archimedes along a large part of the arc of contact. In addition, as an alternative to the modern calculus tools, it is shown how the drive variables can be equally calculated applying some propositions of Archimedes’ classical treatise πeρί ‘eλίκων (On Spirals).

Path (topology)Arc (geometry)symbols.namesakeVariatorAxial thrustArchimedean spiralsymbolsTorqueGeometryGear ratioStoria della meccanica V-belt spirale di ArchimedeContinuously variable transmissionMathematics
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Early Referral to an ALS Center Reduces Several Months the Diagnostic Delay: A Multicenter-Based Study.

2020

Objective: To analyze those factors contributing to the diagnostic delay in ALS.Methods: Consecutive ALS patients were categorized as those studied in departmental hospitals and those studied in a referral ALS center. Demographic and clinical variables, together with data of the diagnostic pathway were collected. Multivariable models were used to assess their effect in the time between symptoms onset and the first neurologist visit (time symptoms-neurologist), in the time between the first neurologist visit and the diagnosis (time neurologist-diagnosis) and in the diagnostic delay.Results: 166 ALS patients with a median diagnostic delay of 11.53 months (IQR: 6.68, 15.23) were included. The …

Pediatricsmedicine.medical_specialtyamyotrophic lateral sclerosisALS UnitClinical variablesReferrallcsh:RC346-42903 medical and health sciences0302 clinical medicinemental disordersmedicine030212 general & internal medicineAmyotrophic lateral sclerosislcsh:Neurology. Diseases of the nervous systemOriginal Researchdiagnostic timelinesbusiness.industryUpper motor neuronmedicine.diseasediagnostic delaynervous system diseasesdiagnostic pathwaymedicine.anatomical_structureNeurologyReferral centerBulbar onsetProgression rateNeurology (clinical)business030217 neurology & neurosurgeryEarly referralFrontiers in neurology
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Graphical models for estimating dynamic networks

2012

Het bepalen van dynamische netwerken met behulp van data is een actief onderzoeksgebied, met name in de systeem biologie. Het schatten van de structuur van een netwerk heeft te maken met het bepalen van de aan of afwezigheid van een relatie tussen de hoekpunten in de graaf. Grafische modellen definiëren deze relaties via conditionele afhankelijkheid. In Gaussiaanse grafische modellen (GGM) wordt verondersteld dat de hoekpunten een normale verdeling volgen. Dit heeft grote voordelen vanwege de computationele handelbaarheid van GGM. Standaard GGM zijn echter niet bruikbaar om grote netwerken te bestuderen, i.e. als het aantal waarnemingen minder is dan het aantal hoekpunten van de graaf. Rece…

Penalized Likelihood Graphical Models Dynamic Networks State-space modelDynamische modellenLatent VariablesNetwerkenmathematische statistiekgraphical modelestimating dynamic networks.Proefschriften (vorm)Settore SECS-S/01 - StatisticaNormale verdelingDynamische systemenSysteembiologieGrafische methoden
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Comparison of free software platforms for the calculation of the 90% confidence interval of f2 similarity factor by bootstrap analysis

2020

Abstract Introduction The calculation of the 90% confidence interval of f2 based on the bootstrap methodology has been proposed and accepted by the main regulatory authorities when the dissolution data shows excessive variability. Different free software platforms allow the calculation of the 90% CI of f2 by means of bootstrapping. Their use in regulatory submissions is growing, but divergent results have been observed between the available software platforms. Therefore, the objective of this work is to analyze the characteristics of these software platforms and evaluate their results. Methods and materials Highly variable in vitro dissolution data from two products were selected. Three dif…

Percentilebusiness.industryPharmaceutical ScienceValue (computer science)02 engineering and technology021001 nanoscience & nanotechnology030226 pharmacology & pharmacyConfidence interval03 medical and health sciencesVariable (computer science)0302 clinical medicineSoftwareBootstrapping (electronics)Similarity (network science)StatisticsTruncation (statistics)0210 nano-technologybusinessMathematicsEuropean Journal of Pharmaceutical Sciences
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