Search results for "FUNCTIONAL"

showing 10 items of 4822 documents

Comparative study of the arterial and lacunary systems of the ventricular myocardium of elasmobranch and teleost fishes.

1983

The typical fish heart has a spongy trabeculated ventricular myocardium (spongiosa) supplied by the venous blood of the intertrabecular spaces (lacunae); hence it is called a "venous heart." However, in some fishes a more complex ventricular muscle is found (mixed type), in which the spongiosa is covered by an outer layer of densely arranged myocardial bundles (compacta). The compacta receives oxygenated blood from the coronary vessels. The objective of this study was to investigate relations between myoarchitecture and blood supply with an emphasis on the hitherto unexplored, putative vascular connections between the arterial and the lacunary circuits. Using histological methods combined w…

Heart VentriclesFishesMixed typeHeartContext (language use)ArteriesVenous bloodAnatomyBiologyVentricular myocardiumHeart Conduction SystemFunctional morphologyVentricular muscleAnimalsInkBlood supplyAnatomyLacunary function
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Heart rate response and functional capacity in patients with chronic heart failure with preserved ejection fraction

2018

Aims: The mechanisms of exercise intolerance in heart failure with preserved ejection fraction (HFpEF) are not yet elucidated. Chronotropic incompetence has emerged as a potential mechanism. We aimed to evaluate whether heart rate (HR) response to exercise is associated to functional capacity in patients with symptomatic HFpEF. Methods and results We prospectively studied 74 HFpEF patients [35.1% New York Heart Association Class III, 53% fe- male, age (mean ± standard deviation) 72.5 ± 9.1 years, and 59.5% atrial fi brillation]. Functional performance was assessed by peak oxygen consumption (peak VO 2 ). The mean (standard deviation) peak VO 2 was 10 ± 2.8 mL/min/kg. The following chronotro…

Heart failure with preserved ejection fractionFunctional capacityChronotropic response
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Preliminary Short-term Results of a Population of Patients Treated with MitraClip therapy: one Center Experience

2017

<p><span>Objectives: This retrospective analysis sought to evaluate 1-month outcomes and therapy effectiveness of a population of patients treated with MitraClip therapy. We describe in this article the preliminary results of primary effictiveness endpoint.</span></p><p><span>Background: Percutaneous Mitral Repair is being developed to treat severe mitral regurgitation (MR),with increasing real-world cases of functional MR(FMR). In the EVEREST(Endovascular Valve Edge-to-Edge Repair Study)II trial,percutaneous device showed superior safety but less reduction in MR at 1year. 4-year outcomes from EVEREST II trial showed no difference in the prevalence of mod…

Heart valvesmedicine.medical_specialtyeducation.field_of_studyMitral regurgitationlcsh:Diseases of the circulatory (Cardiovascular) systemPercutaneousbusiness.industryMitraClipPopulationlcsh:Rlcsh:MedicinePercutaneous approachNyha classNew york heart associationSurgerylcsh:RC666-701MedicineFunctional mrMitraClipbusinesseducationCatheter-based therapyNYHA functional classMitral RegurgitationInternational Cardiovascular Forum Journal
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Spatially localized solutions of the Hammerstein equation with sigmoid type of nonlinearity

2016

Abstract We study the existence of fixed points to a parameterized Hammerstein operator H β , β ∈ ( 0 , ∞ ] , with sigmoid type of nonlinearity. The parameter β ∞ indicates the steepness of the slope of a nonlinear smooth sigmoid function and the limit case β = ∞ corresponds to a discontinuous unit step function. We prove that spatially localized solutions to the fixed point problem for large β exist and can be approximated by the fixed points of H ∞ . These results are of a high importance in biological applications where one often approximates the smooth sigmoid by discontinuous unit step function. Moreover, in order to achieve even better approximation than a solution of the limit proble…

Heaviside step functionIterative methodApplied Mathematics010102 general mathematicsMathematical analysisSigmoid functionFixed point01 natural sciences010305 fluids & plasmasHamiltonian systemFunctional Analysis (math.FA)Mathematics - Functional AnalysisNonlinear systemsymbols.namesakeMathematics - Analysis of PDEs0103 physical sciencessymbolsFOS: MathematicsFitzHugh–Nagumo modelHomoclinic orbit0101 mathematicsAnalysisMathematicsAnalysis of PDEs (math.AP)
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3 He NMR studies on helium-pyrrole, helium-indole, and helium-carbazole systems: a new tool for following chemistry of heterocyclic compounds

2014

The 3He nuclear magnetic shieldings were calculated for free helium atom and He–pyrrole, He–indole, and He–carbazole complexes. Several levels of theory, including Hartree–Fock (HF), Second-order Moller-Plesset Perturbation Theory (MP2), and Density Functional Theory (DFT) (VSXC, M062X, APFD, BHandHLYP, and mPW1PW91), combined with polarization-consistent pcS-2 and aug-pcS-2 basis sets were employed. Gauge-including atomic orbital (GIAO) calculated 3He nuclear magnetic shieldings reproduced accurately previously reported theoretical values for helium gas. 3He nuclear magnetic shieldings and energy changes as result of single helium atom approaching to the five-membered ring of pyrrole, indo…

Helium atomCarbazoleChemical shiftchemistry.chemical_elementGeneral ChemistryRing (chemistry)chemistry.chemical_compoundchemistryAtomic orbitalComputational chemistryPhysics::Atomic and Molecular ClustersMoleculePhysical chemistryGeneral Materials ScienceDensity functional theoryPhysics::Atomic PhysicsHeliumMagnetic Resonance in Chemistry
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A spectral approach to a constrained optimization problem for the Helmholtz equation in unbounded domains

2014

We study some convergence issues for a recent approach to the problem of transparent boundary conditions for the Helmholtz equation in unbounded domains (Ciraolo et al. in J Comput Phys 246:78–95, 2013) where the index of refraction is not required to be constant at infinity. The approach is based on the minimization of an integral functional, which arises from an integral formulation of the radiation condition at infinity. In this paper, we implement a Fourier–Chebyshev collocation method to study some convergence properties of the numerical algorithm; in particular, we give numerical evidence of some convergence estimates available in the literature (Ciraolo in Helmholtz equation in unbou…

Helmholtz equationApplied MathematicsMathematical analysisTransparent boundary conditionComputational mathematicsFOS: Physical sciencesNumerical Analysis (math.NA)Mathematical Physics (math-ph)Electric-field integral equationComputational MathematicsCollocation methodConvergence (routing)Computational MathematicFOS: MathematicsMathematics - Numerical AnalysisBoundary value problemHelmholtz equationMinimization of integral functionalSpectral methodSpectral methodConstant (mathematics)Mathematical PhysicsMathematics
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Global stability analysis of a delay cell-population model of hepatitis B infection with humoral immune response

2021

In this work, we propose and investigate a delay cell population model of hepatitis B virus (HBV) infection. We suppose spatial diffusion of free HBV particles, and use a Beddington-DeAngelis incid...

Hepatitis B virusGeneral MathematicsCellvirus diseasesmedicine.disease_causeVirologydigestive system diseasesComputer Science ApplicationsHepatitis B infectionmedicine.anatomical_structureImmune systemPopulation modelLyapunov functionalmedicineSpatial diffusionMathematicsDynamical Systems
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Recent Advances in Derivation of Functional Hepatocytes from Placental Stem Cells

2013

Abstract: End-stage liver diseases are one of the leading causes of death in the world. Often orthotopic liver transplantation represents the final therapeutic choice. The limits of this approach are the scarcity of donor livers available, and the many side effects related to the administration of immune suppressants to the patients. Cellular therapy for liver diseases is increasingly being viewed as a promising strategy to provide hepatocytes to replenish the parenchymal cells of the organ. This technique suffers of some important limitations, such as the difficulty in isolating sufficient cell numbers (e.g. when adult or foetal hepatocytes are used for transplantation), the limited viabil…

Hepatocyte differentiationMesenchymal stem cells Wharton’s jelly amniotic fluid amniotic membrane immune modulation umbilical cord hepatocyte differentiation functional assays inflammation fibrosis regenerative medicine tissue repair.Settore BIO/16 - Anatomia UmanaMesenchymal stem cellBiologyPlacenta cord bankingRegenerative medicineCell therapySettore MED/38 - Pediatria Generale E Specialisticamedicine.anatomical_structureDevelopmental NeuroscienceImmunologyCancer researchmedicineBone marrowStem cellDevelopmental BiologyAdult stem cellThe Open Tissue Engineering and Regenerative Medicine Journal
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949 IDENTIFICATION OF TWO CLINICALLY DISTINCT SUBTYPES IN AUTOIMMUNE HEPATITIS BY COMPARATIVE FUNCTIONAL GENOMICS

2013

Conclusion: Incidence of autoimmune hepatitis is increasing, as other autoimmune diseases in developed countries. The main recognised hypothesis is the ‘hygienist theory’ (improvement of hygien leading to a decrease in infections) with few putative non exclusive mechanisms involving antigenic competition, extension of immune regulation induced by exogenous bacterial antigen or Toll Like Receptors.

HepatologyAntigenImmunologyImmune regulationmedicineIdentification (biology)Autoimmune hepatitisBacterial antigenBiologyReceptorBioinformaticsmedicine.diseaseFunctional genomicsJournal of Hepatology
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Hydrocracking ofn-heptane. Study of NiO-MoO3catalysts supported on a HY ultrastable zeolite

1986

The hydrocracking of n-heptane in the temperature range of 573 to 623 K and at 2.45 × 106 Pa pressure has been employed as a test reaction for the study of Ni—Mo bifunctional catalysts supported on a HY ultrastable zeolite. Two groups of catalysts containing 8 and 12 wt% of MoO3 and different amounts of NiO have been studied. In both series a maximum in the activity has been obtained for catalysts with a Ni/Mo atomic ratio of 0.8-1.0. The order of the impregnation of the oxides can have little influence on the activity. The most active catalyst has been obtained when the zeolite is exchanged with NH+4 ions until the Na+ level is less than 2% of the original and calcined at 823 K to obtain a…

HeptaneChemistryStereochemistryGeneral Chemical EngineeringNon-blocking I/OCatalysislaw.inventionchemistry.chemical_compoundCarbonium ionlawAtomic ratioCalcinationZeoliteBifunctionalNuclear chemistryThe Canadian Journal of Chemical Engineering
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