Now showing items 1-20 of 428

  • The 1 : √2 mode interaction and heteroclinic networks in Boussinesq convection 

    Podvigina, Olga; Ashwin, Peter (Elsevier, 2007)
    Methods of equivariant bifurcation theory are applied to Boussinesq convection in a plane layer with stress-free 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 

    de Patoul, Judith; Inhester, Bernd; Feng, L; Wiegelmann, T (Springer Verlag, 2011-11-17)
    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 

    de Patoul, Judith; Foullon, Claire; Riley, Pete (American Astronomical Society, 2015-11-17)
    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 

    Bajer, Konrad; Bassom, Andrew P.; Gilbert, Andrew D. (Cambridge University Press, 2001)
    The spiral wind-up 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 turn-over ...
  • Acceleration of one-dimensional mixing by discontinuous mappings 

    Ashwin, Peter; Nicol, Matthew; Kirkby, Norman (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 

    Tamagnini, F; Novelia, J; Kerrigan, TL; Brown, JT; Tsaneva-Atanasova, KT; Randall, AD (Frontiers, 2015-10-14)
    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 ...
  • Altered intrinsic pyramidal neuron properties and pathway-specific synaptic dysfunction underlie aberrant hippocampal network function in a mouse model of Tauopathy. 

    Booth, Clair A.; Witton, J; Nowacki, J; Tsaneva-Atanasova, Krasimira; Jones, MW; Randall, AD; Brown, JT (Society for Neuroscience -, 2016-01-13)
    The formation and deposition of tau protein aggregates is proposed to contribute to cognitive impairments in dementia by disrupting neuronal function in brain regions, including the hippocampus. We used a battery of in ...
  • Alternative stable scroll waves and conversion of autowave turbulence 

    Foulkes, A. J.; Barkley, D.; Biktashev, V. N.; Biktasheva, I. V. (American Institute of Physics, 2010)
    Rotating spiral and scroll waves (vortices) are investigated in the FitzHugh-Nagumo model of excitable media. The focus is on a parameter region in which there exists bistability between alternative stable vortices with ...
  • Amplified mid-latitude planetary waves favour particular regional weather extremes 

    Screen, James A.; Simmonds, Ian (Nature Publishing Group, 2014)
    There has been an ostensibly large number of extreme weather events in the Northern Hemisphere mid-latitudes during the past decade [1]. An open question that is critically important for scientists and policy makers is ...
  • Analysis of anchor-size effects on pinned scroll waves and measurement of filament rigidity. 

    Nakouzi, E; Jiménez, ZA; Biktashev, V.N.; Steinbock, O (American Physical Society, 2014-04-02)
    Inert, spherical heterogeneities can pin three-dimensional scroll waves in the excitable Belousov-Zhabotinsky reaction. Three pinning sites cause initially circular rotation backbones to approach equilateral triangles. The ...
  • An analytical approach to initiation of propagating fronts 

    Idris, I.; Biktashev, V. N. (American Physical Society, 2008)
    We consider the problem of initiation of a propagating wave in a one-dimensional excitable fibre. In the Zeldovich-Frank-Kamenetsky equation, a.k.a. Nagumo equation, the key role is played by the "critical nucleus'' solution ...
  • An Analytical Model for On-chip Interconnects in Multimedia Embedded Systems 

    Wu, Yulei; Min, Geyong; Zhu, Dakai; Yang, Laurence T. (Association for Computing Machinery (ACM), 2013)
    The traffic pattern has significant impact on the performance of network-on-chip. Many recent studies have shown that multimedia applications can be supported in on-chip interconnects. Driven by the motivation of evaluating ...
  • Analytically Solvable Asymptotic Model of Atrial Excitability 

    Simitev, R. D.; Biktashev, V. N. (2009-05-25)
    We report a three-variable 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 

    Ashwin, Peter; Breakspear, Michael (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 ...
  • Anthropogenic perturbation of the carbon fluxes from land to ocean 

    Regnier, P; Friedlingstein, P; Ciais, P; Mackenzie, FT; Gruber, N; Janssens, IA; Laruelle, GG; Lauerwald, R; Luyssaert, S; Andersson, AJ; Arndt, S; Arnosti, C; Borges, AV; Dale, AW; Gallego-Sala, Angela V.; Goddéris, Y; Goossens, N; Hartmann, J; Heinze, C; Ilyina, T; Joos, F; Larowe, DE; Leifeld, J; Meysman, FJR; Munhoven, G; Raymond, PA; Spahni, R; Suntharalingam, P; Thullner, M (Nature Publishing Group, 2013-06-09)
    A substantial amount of the atmospheric carbon taken up on land through photosynthesis and chemical weathering is transported laterally along the aquatic continuum from upland terrestrial ecosystems to the ocean. So far, ...
  • Anti-phase Signature of Flare Generated Transverse Loop Oscillation 

    White, R.S.; Verwichte, E.; Foullon, Claire (American Astronomical Society / IOP Publishing, 2013)
    Transverse loop oscillations observed by the Atmospheric Imaging Assembly instrument on the Solar Dynamics Observatory spacecraft are studied after an impulsive solar flare eruption on 2012 May 8. We have found that a ...
  • Arctic amplification decreases temperature variance in Northern mid- to high-latitudes 

    Screen, James A. (Nature Publishing Group, 2014)
    Changes in climate variability are arguably more important for society and ecosystems than changes in mean climate, especially if they translate into altered extremes [1, 2, 3]. There is a common perception and growing ...
  • Are changes in global precipitation constrained by the tropospheric energy budget? 

    Lambert, F. Hugo; Allen, Myles R. (American Meteorological Society, 2009)
    A tropospheric energy budget argument is used to analyze twentieth-century precipitation changes. It is found that global and ocean-mean general circulation model (GCM) precipitation changes can be understood as being due ...
  • Asymmetry of magnetosheath flows and magnetopause shape during low Alfven Mach number solar wind 

    Lavraud, B.; Larroque, E.; Budnik, E.; Genot, V.; Borovsky, J.E.; Dunlop, M.W.; Foullon, Claire; Hasegawa, H.; Jacquey, C.J.; Nykyri, Katariina; Ruffenach, A.; Taylor, M.G.G.T.; Dandouras, I.; Reme, Henri (American Geophysical Union (AGU), 2013)
    Previous works have emphasized the significant influence of the solar wind Alfvén Mach number (MA) on magnetospheric dynamics. Here we report statistical, observational results that pertain to changes in the magnetosheath ...
  • Asymptotic analysis and analytical solutions of a model of cardiac excitation. 

    Biktashev, V. N.; Suckley, R.; Elkin, Y. E.; Simitev, R. D. (Springer Verlag, 2008)
    We describe an asymptotic approach to gated ionic models of single-cell cardiac excitability. It has a form essentially different from the Tikhonov fast-slow form assumed in standard asymptotic reductions of excitable ...