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Distribution of Directional Change as a Signature of Complex Dynamics
PNAS (2013)
  • Stanislav Burov, James Frank Institute
  • S.M. Ali Tabei, University of Northern Iowa
  • Toan Huynh
  • Michael P. Murrell
  • Louis H. Philipson
  • Stuart A. Rice, James Frank Institute
  • Margaret L. Gardel, James Frank Institute
  • Norbert F. Scherer
  • Aaron R. Dinner, The University of Illinois at Chicago
Analyses of random walks traditionally use the mean square displacement (MSD) as an order parameter characterizing dynamics. We show that the distribution of relative angles of motion between successive time intervals of random walks in two or more dimensions provides information about stochastic processes beyond the MSD. We illustrate the behavior of this measure for common models and apply it to experimental particle tracking data. For a colloidal system, the distribution of relative angles reports sensitively on caging as the density varies. For transport mediated by molecular motors on filament networks in vitro and in vivo, we discover self-similar properties that cannot be described by existing models and discuss possible scenarios that can lead to the elucidated statistical features.
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Citation Information
Stanislav Burov, S.M. Ali Tabei, Toan Huynh, Michael P. Murrell, et al.. "Distribution of Directional Change as a Signature of Complex Dynamics" PNAS Vol. 110 Iss. 49 (2013)
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