Search results for "fusion [vector boson]"

showing 10 items of 526 documents

Pattern formation and bifurcation analysis for some chemotaxis-reaction-diffusion systems

Pattern formation Chemotaxis Reaction-diffusion system bifurcation normal formSettore MAT/07 - Fisica Matematica
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Pattern formation driven by cross–diffusion in a 2D domain

2012

Abstract In this work we investigate the process of pattern formation in a two dimensional domain for a reaction–diffusion system with nonlinear diffusion terms and the competitive Lotka–Volterra kinetics. The linear stability analysis shows that cross-diffusion, through Turing bifurcation, is the key mechanism for the formation of spatial patterns. We show that the bifurcation can be regular, degenerate non-resonant and resonant. We use multiple scales expansions to derive the amplitude equations appropriate for each case and show that the system supports patterns like rolls, squares, mixed-mode patterns, supersquares, and hexagonal patterns.

Pattern formationFOS: Physical sciencesSaddle-node bifurcationPattern Formation and Solitons (nlin.PS)Dynamical Systems (math.DS)Bifurcation diagramDomain (mathematical analysis)Reaction–diffusion systemFOS: MathematicsMathematics - Dynamical SystemsBifurcationMathematical PhysicsMathematicsApplied MathematicsNonlinear diffusionTuring instabilityDegenerate energy levelsMathematical analysisGeneral EngineeringGeneral MedicineMathematical Physics (math-ph)Nonlinear Sciences - Pattern Formation and SolitonsBiological applications of bifurcation theoryComputational MathematicsAmplitude equationGeneral Economics Econometrics and FinanceSubcritical bifurcationAnalysis
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Mild twin–twin transfusion syndrome: Clinical report.

2008

Pediatricsmedicine.medical_specialtyClinical reportbusiness.industryPediatrics Perinatology and Child HealthTransfusion twinsmedicineObstetrics and GynecologybusinessTwin Twin Transfusion Syndrome
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A SUBCRITICAL BIFURCATION FOR A NONLINEAR REACTION–DIFFUSION SYSTEM

2010

In this paper the mechanism of pattern formation for a reaction-diffusion system with nonlinear diffusion terms is investigated. Through a linear stability analysis we show that the cross-diffusion term allows the pattern formation. To predict the form and the amplitude of the pattern we perform a weakly nonlinear analysis. In the supercritical case the Stuart-Landau equation is found, which rules the evolution of the amplitude of the most unstable mode. With the increasing distance from the bifurcation value of the cross-diffusion parameter, the weakly nonlinear analysis fails and a Fourier–Galerkin approach is adopted. In the subcritical case the weakly nonlinear analysis must be pushed u…

Period-doubling bifurcationNonlinear systemTranscritical bifurcationNonlinear resonanceMathematical analysisReaction–diffusion systemSaddle-node bifurcationBifurcation diagramNonlinear Sciences::Pattern Formation and SolitonsBifurcationMathematicsWaves and Stability in Continuous Media
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Correction: Widespread white matter microstructural abnormalities in bipolar disorder: evidence from mega- and meta-analyses across 3033 individuals

2019

Fronto-limbic white matter (WM) abnormalities are assumed to lie at the heart of the pathophysiology of bipolar disorder (BD); however, diffusion tensor imaging (DTI) studies have reported heterogeneous results and it is not clear how the clinical heterogeneity is related to the observed differences. This study aimed to identify WM abnormalities that differentiate patients with BD from healthy controls (HC) in the largest DTI dataset of patients with BD to date, collected via the ENIGMA network. We gathered individual tensor-derived regional metrics from 26 cohorts leading to a sample size of N = 3033 (1482 BD and 1551 HC). Mean fractional anisotropy (FA) from 43 regions of interest (ROI) a…

PharmacologyAdultMaleBipolar DisorderCorrectionBrainDiagnostic markersBiologyTranslational researchmedicine.diseaseMega-White MatterCorpus CallosumWhite matterPsychiatry and Mental healthmedicine.anatomical_structureDiffusion Tensor ImagingNeural PathwaysmedicineHumansFemaleBipolar disorderClinical psychologyNeuropsychopharmacology
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Physicochemical stability of human insulin 1 I.U./mL infusion solution in 50 mL polypropylene syringes

2021

Abstract Objectives The objective of this study was to investigate the physicochemical stability of human insulin 1 I.U./mL injection solutions (Insuman® Rapid) diluted with 0.9% NaCl solution in 50 mL disposable three-piece polypropylene syringes and stored refrigerated or at room temperature. Methods 1 I.U./mL test solutions were prepared with Insuman® Rapid and 0.9% sodium chloride infusion solution in 50 mL Original-Perfusor® syringes and BD® Perfusion syringes. Test solutions were stored for 90 days at 2–8 °C/dark or 48 h at 20–25 °C/diffuse room light in order to determine chemical stability. Additional test solutions were stored 28 days at 2–8 °C/dark followed by 24 h at 20–25 °C/dif…

PharmacologyPolypropyleneChromatographyInternational unitphysicochemical stabilityInfusion solutionPharmacyRM1-950polypropylene syringechemistry.chemical_compoundchemistryHuman insulinhuman insulinPharmacology (medical)intravenous injectionTherapeutics. PharmacologyHD9665-9675Pharmaceutical industryPharmaceutical Technology in Hospital Pharmacy
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Polymorphic and regular localized activity structures in a two-dimensional two-component reaction–diffusion lattice with complex threshold excitation

2010

Abstract Space–time dynamics of the system modeling collective behaviour of electrically coupled nonlinear units is investigated. The dynamics of a local cell is described by the FitzHugh–Nagumo system with complex threshold excitation. It is shown that such a system supports formation of two distinct kinds of stable two-dimensional spatially localized moving structures without any external stabilizing actions. These are regular and polymorphic structures. The regular structures preserve their shape and velocity under propagation while the shape and velocity as well as other integral characteristics of polymorphic structures show rather complex temporal behaviour. Both kinds of structures r…

Phase spaceLattice (order)Quasiperiodic functionReaction–diffusion systemBound statePattern formationStatistical and Nonlinear PhysicsGeometryStatistical physicsCondensed Matter PhysicsBifurcationMultistabilityMathematicsPhysica D: Nonlinear Phenomena
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On the Semiconductor Spectroscopy for Identification of Emergent Contaminants in Transparent Mediums

2021

In this chapter, we present a theoretical study of photoelectronic processes in experimental silicon \({n}^{+}{\text{-}}p{\text{-}}{n}^{+}\) structures with applications in identifying emergent contaminants in aqueous medium. Contribution due to various mechanisms of photon absorption to the total photocurrent is calculated. Various mechanisms, such as the influence of tunneling on the spectral characteristic and selective spectral photosensitivity of samples under investigation were investigated. The nature of the relationship between energy parameters of the absorbed waves and the structural parameters is revealed. Expressions are obtained for photocurrent with and without external diffus…

PhotocurrentMaterials scienceSiliconbusiness.industrychemistry.chemical_elementMolecular physicsSemiconductorchemistryAttenuation coefficientDiffusion currentAbsorption (logic)businessSpectroscopyEnergy (signal processing)
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A partially reflecting random walk on spheres algorithm for electrical impedance tomography

2015

In this work, we develop a probabilistic estimator for the voltage-to-current map arising in electrical impedance tomography. This novel so-called partially reflecting random walk on spheres estimator enables Monte Carlo methods to compute the voltage-to-current map in an embarrassingly parallel manner, which is an important issue with regard to the corresponding inverse problem. Our method uses the well-known random walk on spheres algorithm inside subdomains where the diffusion coefficient is constant and employs replacement techniques motivated by finite difference discretization to deal with both mixed boundary conditions and interface transmission conditions. We analyze the global bias…

Physics and Astronomy (miscellaneous)random diffusion coefficientvariance reductionMonte Carlo method010103 numerical & computational mathematicsControl variates01 natural sciencesdiscontinuous diffusion coefficientrandom walk on spheresFOS: Mathematics[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]Mathematics - Numerical Analysis0101 mathematicsElectrical impedance tomographyMathematicsNumerical AnalysisApplied MathematicsProbabilistic logicEstimatorMonte Carlo methodsreflecting Brownian motionNumerical Analysis (math.NA)Inverse problemRandom walkComputer Science Applications010101 applied mathematicsComputational MathematicsModeling and SimulationVariance reductionAlgorithmelectrical impedance tomographyJournal of Computational Physics
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An exact thermodynamical model of power-law temperature time scaling

2016

In this paper a physical model for the anomalous temperature time evolution (decay) observed in complex thermodynamical system in presence of uniform heat source is provided. Measures involving temperatures T with power-law variation in time as T(t)∝tβ with β∈R shows a different evolution of the temperature time rate T(t) with respect to the temperature time-dependence T(t). Indeed the temperature evolution is a power-law increasing function whereas the temperature time rate is a power-law decreasing function of time. Such a behavior may be captured by a physical model that allows for a fast thermal energy diffusion close to the insulated location but must offer more resistance to the therm…

PhysicsAnomalous conductionDiffusion equationField (physics)business.industryPower-lawTime evolutionTemperature evolutionGeneral Physics and AstronomyAnomalous conduction; Fractional derivative; Fractional Transport; Power-law; Temperature evolution;Function (mathematics)Fractional derivative01 natural sciencesPower law010305 fluids & plasmasFractional Transport010101 applied mathematics0103 physical sciencesStatistical physics0101 mathematicsDiffusion (business)businessSettore ICAR/08 - Scienza Delle CostruzioniScalingThermal energy
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