Now showing items 1-7 of 7

  • Amplitude equation approach to spatiotemporal dynamics of cardiac alternans 

    Echebarría Domínguez, Blas; Karma, Alain (American Physical Society, 2007-11-30)
    Article
    Open Access
    Amplitude equations are derived that describe the spatiotemporal dynamics of cardiac alternans during periodic pacing of one- B. Echebarria and A. Karma, Phys. Rev. Lett. 88, 208101 2002 and twodimensional homogeneous ...
  • Crack front segmentation and facet coarsening in mixed-mode fracture 

    Chen, Chih-Hung; Cambonie, Tristan; Lazarus, Veronique; Nicoli, Matteo; Pons Rivero, Antonio Javier; Karma, Alain (2015-12-30)
    Article
    Open Access
    A planar crack generically segments into an array of “daughter cracks” shaped as tilted facets when loaded with both a tensile stress normal to the crack plane (mode I) and a shear stress parallel to the crack front (mode ...
  • Helical crack-front instability in mixed-mode fracture 

    Pons Rivero, Antonio Javier; Karma, Alain (2010-03-04)
    Article
    Restricted access - publisher's policy
    [...]We show that the dynamically preferred unstable wavelength is governed by the balance of the destabilizing effect of far-field stresses and the stabilizing effect of cohesive forces on the process zone scale, and we ...
  • Instability and spatiotemporal dynamics of alternans in paced cardiac tissue 

    Echebarría Domínguez, Blas; Karma, Alain (2002)
    Article
    Open Access
    We derive an equation that governs the spatiotemporal dynamics of small amplitude alternans in paced cardiac tissue. We show that a pattern-forming linear instability leads to the spontaneous formation of stationary or ...
  • Mechanisms for initiation of cardiac discordant alternans 

    Echebarría Domínguez, Blas; Karma, Alain (Springer, 2007-07-31)
    Article
    Restricted access - publisher's policy
    Electrical alternans, defined as a beat-to-beat change in the duration of the excited phase of cardiac cells, is among the known precursors of sudden cardiac death. It may appear as concordant (all the tissue presenting ...
  • Onset of sidebranching in directional solidification 

    Echebarría Domínguez, Blas; Karma, Alain; Gurevich, Sebastian (2010-02-26)
    Article
    Open Access
    We use a computationally efficient phase-field formulation [B. Echebarria et al., Phys. Rev. E 70, 061604 (2004)] to investigate the origin and dynamics of sidebranching in directional solidification for realistic ...
  • Spatiotemporal control of cardiac alternans 

    Echebarría Domínguez, Blas; Karma, Alain (Institute of Physics (IOP), 2002)
    Article
    Restricted access - publisher's policy
    Electrical alternans are believed to be linked to the onset of life-threatening ventricular arrhythmias and sudden cardiac death. Recent studies have shown that alternans can be suppressed temporally by dynamic feedback ...