Monday March 10, 2014
(Refreshments served at 10:45 am, HSCI-224)
Fig: Dynamics of order parameter measuring a dynamical instability in a two dimensional model of a heart cell.
Electrical alternans is a beat-to-beat alternation in the amplitude of the electrocardiogram (ECG) which has been shown to be a precursor to various heart rhythm disorders. Many studies have traced this phenomenon to a nonlinear instability of a heart cell that is driven by a periodic stimulus. In this talk I will present an overview of the nonlinear response of heart cells, and show how subcellular processes can lead to complex dynamical behavior. In particular, I highlight the important role of stochastic signaling between ion channels and argue that nonlinearities inherent in the signaling architecture are essential to understand instabilities in the whole heart. Furthermore, I will present evidence that the transition to alternans occurs via an order-disorder phase transition in the Ising universality class. Based on these results I will then argue that the onset of alternans in heart cells exhibits universal features common to a wide range of physical systems.
See the colloquium schedule and its archive of previous talks
Colloquia are scheduled to start Mondays at 11:15am sharp in Peterson Hall 2, Room 110 (PH2-110, map). Refreshments are served from 10:45am to 11:05am in Room HSCI-224 (next to the department office) and everyone is invited to mingle with faculty and students!
We acknowledge with gratitude donations and support from the following present sponsors:
We also acknowledge with gratitude our past donors: The Forty-Niner Shops, Inc., The Northrop Grumman Foundation, Sandra Dana, Anonymous.
If you wish to support the Colloquium, please contact the colloquium coordinator or the department chair. Thank you!
|Date||Title||Speaker and Affiliation|
|January 27||Laser Eye Surgery: Applied Physics at its Finest||F. Raksi|
|February 3||Computational Approach to Undergraduate Physics Laboratory||Zoltan Papp, CSULB|
|February 10||Superconducting States in pseudo-Landau levels of Strained Graphene||Yafis Barlas, UCR|
|February 17||Heating up the Vacuum: a new Spin on QCD at RHIC||Kenneth R. Barish, UCR|
|February 24||My Favorite Elementary Particle: The Neutrino||James Hill, CSUDH|
|March 3||Space Situational Awareness: Providing advanced, innovative space surveillance technologies to the warfighter||Kenneth A. Abeloe
Integrity Applications Incorporated
|March 10||Nonlinear dynamics and phase transitions in heart cells||Y. Shiferaw, CUN|
|March 17||TBA||J. Lau, UCR|
|March 24||TBA||A. Manohar, UCSD|
|April 28||TBA||Dmitri Krioukov, USCD|
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