Search results for "Fourier analysi"

showing 4 items of 114 documents

Evaluation of the Complexity of Myocardial Activation During Ventricular Fibrillation. An Experimental Study

2013

A B S T R A C T Introduction and objectives: An experimental model is used to analyze the characteristics of ventricular fibrillation in situations of variable complexity, establishing relationships among the data produced by different methods for analyzing the arrhythmia. Methods: In 27 isolated rabbit heart preparations studied under the action of drugs (propranolol and KB-R7943) or physical procedures (stretching) that produce different degrees of change in the complexity of myocardial activation during ventricular fibrillation, use was made of spectral, morphological, and mapping techniques to process the recordings obtained with epicardial multielectrodes. Results: The complexity of ve…

medicine.medical_specialtyMultivariate analysisCoefficient of variationmedia_common.quotation_subjectComplexity indexsymbols.namesakeInternal medicinemedicineAnimalsmedia_commonVariablesbusiness.industrySpectral densityHeartGeneral Medicinemedicine.diseaseFourier analysisVentricular FibrillationVentricular fibrillationCardiologysymbolsRabbitsElectrophysiologic Techniques CardiacbusinessBiological systemEnergy (signal processing)Revista Española de Cardiología (English Edition)
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Analytical model for the long- distance tracer-transport in plants

2011

International audience; Recent investigations of long-distance transport in plants using non-invasive tracer techniques such as C radiolabeling monitored by positron emission tomography (PET) combined with magnetic resonance imaging (MRI) revealed the need of dedicated methods to allow a quantitative data analysis and comparison of such experiments. A mechanistic compartmental tracer transport model is presented, defined by a linear system of partial differential equations (PDEs). This model simplifies the complexity of axial transport and lateral exchanges in the transport pathways of plants (e.g. the phloem) by simulating transport and reversible exchange within three compartments using j…

metabolism [Plant Structures]Transport pathwaysPlant RootsNuclear magnetic resonanceCarbon RadioisotopesPositron emissiontomography(PET)11CPartial differential equationFourier AnalysisApplied MathematicsLinear systemfood and beveragesGeneral MedicinePlantsphysiology [Biological Transport]Magnetic Resonance Imagingmetabolism [Plants]Jddc:580Modeling and SimulationPositron emission tomography (PET)Beta vulgarisGeneral Agricultural and Biological SciencesBiological systemmetabolism [Zea mays]AlgorithmsSimulationStatistics and ProbabilityMaterials scienceC-11metabolism [Phloem]Data analysisPhloemZea maysModels BiologicalGeneral Biochemistry Genetics and Molecular Biologymetabolism [Plant Roots]RaphanusXylemTRACERddc:570metabolism [Carbon Radioisotopes]Computer SimulationSensitivity (control systems)Radioactive TracersGeneral Immunology and Microbiologymetabolism [Xylem]Biological Transportmetabolism [Raphanus]metabolism [Beta vulgaris]Positron-Emission TomographyConstant (mathematics)Plant Structures
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Aesthetics and smile: correlation between upper central incisor morphology and face shape

2022

smile aestheticsFourier analysisshape of face and central incisorSettore MED/28 - Malattie Odontostomatologiche
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Mappings of finite distortion: Reverse inequalities for the Jacobian

2007

Let f be a nonconstant mapping of finite distortion. We establish integrability results on 1/Jf by studying weights that satisfy a weak reverse Holder inequality where the associated constant can depend on the ball in question. Here Jf is the Jacobian determinant of f.

symbols.namesakePure mathematicsDifferential geometryFourier analysisMathematical analysisJacobian matrix and determinantsymbolsGeometry and TopologyBall (mathematics)Reverse holder inequalityMathematicsJournal of Geometric Analysis
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