Browsing Mathematics by Title
Now showing items 120 of 296

The 1 : √2 mode interaction and heteroclinic networks in Boussinesq convection
(Elsevier, 2007)Methods of equivariant bifurcation theory are applied to Boussinesq convection in a plane layer with stressfree horizontal boundaries and an imposed square lattice periodicity in the horizontal directions. We consider ... 
2D and 3D polar plume analysis from the three vantage positions of STEREO/EUVI A, B, and SOHO/EIT
(Springer Verlag, 20111117)Polar plumes are seen as elongated objects starting at the solar polar regions. Here, we analyze these objects from a sequence of images taken simultaneously by the three spacecraft telescopes STEREO/EUVI A and B, and ... 
3D electron density distribution in the solar corona during solar minima: assessment for more realistic solar wind modelling
(American Astronomical Society, 20151117)Knowledge of the electron density distribution in the solar corona put constraints on the magnetic field configurations for coronal modeling and on initial conditions for solar wind modeling. We work with polarized ... 
Accelerated diffusion in the centre of a vortex
(Cambridge University Press, 2001)The spiral windup and diffusive decay of a passive scalar in circular streamlines is considered. An accelerated diffusion mechanism operates to destroy scalar fluctuations on a time scale of order P1/3 times the turnover ... 
Acceleration of onedimensional mixing by discontinuous mappings
(Elsevier, 2002)The paper considers a simple class of models for mixing of a passive tracer into a bulk material that is essentially one dimensional. We examine the relative rates of mixing due to diffusion, stretch and fold operations ... 
Altered intrinsic excitability of hippocampal CA1 pyramidal neurons in aged PDAPP mice
(Frontiers, 20151014)Amyloidopathy involves the accumulation of insoluble amyloid b (Ab) species in the brain’s parenchyma and is a key histopathological hallmark of Alzheimer’s disease (AD). Work on transgenic mice that overexpress Ab ... 
Alternative stable scroll waves and conversion of autowave turbulence
(American Institute of Physics, 2010)Rotating spiral and scroll waves (vortices) are investigated in the FitzHughNagumo model of excitable media. The focus is on a parameter region in which there exists bistability between alternative stable vortices with ... 
Amplified midlatitude planetary waves favour particular regional weather extremes
(Nature Publishing Group, 2014)There has been an ostensibly large number of extreme weather events in the Northern Hemisphere midlatitudes during the past decade [1]. An open question that is critically important for scientists and policy makers is ... 
An analytical approach to initiation of propagating fronts
(American Physical Society, 2008)We consider the problem of initiation of a propagating wave in a onedimensional excitable fibre. In the ZeldovichFrankKamenetsky equation, a.k.a. Nagumo equation, the key role is played by the "critical nucleus'' solution ... 
An Analytical Model for Onchip Interconnects in Multimedia Embedded Systems
(Association for Computing Machinery (ACM), 2013)The traffic pattern has significant impact on the performance of networkonchip. Many recent studies have shown that multimedia applications can be supported in onchip interconnects. Driven by the motivation of evaluating ... 
Analytically Solvable Asymptotic Model of Atrial Excitability
(20090525)We report a threevariable simplified model of excitation fronts in human atrial tissue. The model is derived by novel asymptotic techniques \new{from the biophysically realistic model of Courtemanche et al (1998) in ... 
Anisotropic properties of riddled basins
(Elsevier, 2001)We consider some general properties of chaotic attractors with riddled basins of attraction (basins with positive measure but open dense complements) in dynamical systems with symmetries. We investigate how a basin of ... 
Are changes in global precipitation constrained by the tropospheric energy budget?
(American Meteorological Society, 2009)A tropospheric energy budget argument is used to analyze twentiethcentury precipitation changes. It is found that global and oceanmean general circulation model (GCM) precipitation changes can be understood as being due ... 
Asymptotic analysis and analytical solutions of a model of cardiac excitation.
(Springer Verlag, 2008)We describe an asymptotic approach to gated ionic models of singlecell cardiac excitability. It has a form essentially different from the Tikhonov fastslow form assumed in standard asymptotic reductions of excitable ... 
Asymptotic and numerical solutions of the initial value problem in rotating planetary fluid cores
(Oxford University Press / Royal Astronomical Society, 2010)An initial state of fluid motion in planetary cores or atmospheres, excited, for example, by the giant impact of an asteroid or an earthquake and then damped by viscous dissipation, decays towards the state of rigidbody ... 
Asymptotic properties of mathematical models of excitability.
(Royal Society, 2006)We analyse small parameters in selected models of biological excitability, including HodgkinHuxley (Hodgkin & Huxley 1952 J. Physiol.117, 500544) model of nerve axon, Noble (Noble 1962 J. Physiol.160, 317352) model of ... 
Asymptotic theory of resonant flow in a spheroidal cavity driven by latitudinal libration
(Cambridge University Press, 2012) 
Asymptotics of conduction velocity restitution in models of electrical excitation in the heart.
(Springer Verlag, 2011)We extend a nonTikhonov asymptotic embedding, proposed earlier, for calculation of conduction velocity restitution curves in ionic models of cardiac excitability. Conduction velocity restitution is the simplest nontrivial ... 
The atmospheric response to three decades of observed arctic sea ice loss
(American Meteorological Society, 2013)Arctic sea ice is declining at an increasing rate with potentially important repercussions. To understand better the atmospheric changes that may have occurred in response to Arctic sea ice loss, this study presents results ... 
Attractors of a randomly forced electronic oscillator
(Elsevier, 1999)This paper examines an electronic oscillator forced by a pseudorandom noise signal. We give evidence of the existence of one or more random attractors for the system depending on noise amplitude and system parameters. ...