Issue
EPL
Volume 87, Number 2, July 2009
Article Number 20003
Number of page(s) 6
Section General
DOI http://dx.doi.org/10.1209/0295-5075/87/20003
Published online 05 August 2009
EPL, 87 (2009) 20003
DOI: 10.1209/0295-5075/87/20003

Dynamics of path aggregation in the presence of turnover

Debasish Chaudhuri1, Peter Borowski2, P. K. Mohanty3 and Martin Zapotocky1, 4

1   Max Planck Institute for the Physics of Complex Systems - Nöthnitzer Strasse 38, 01187 Dresden, Germany, EU
2   Department of Mathematics, University of British Columbia - Vancouver, BC, Canada V6T 1Z2
3   TCMP Division, Saha Institute of Nuclear Physics - 1/AF Bidhan Nagar, Kolkata 700064, India
4   Institute of Physiology, Academy of Sciences of the Czech Republic - Videnska 1083, 14220 Praha 4, Czech Republic, EU

zapotocky@biomed.cas.cz

received 16 April 2009; accepted in final form 8 July 2009; published July 2009
published online 5 August 2009

Abstract
We investigate the slow time scales that arise from aging of the paths during the process of path aggregation. This is studied using Monte Carlo simulations of a model aiming to describe the formation of fascicles of axons mediated by contact axon-axon interactions. The growing axons are represented as interacting directed random walks in two spatial dimensions. To mimic axonal turnover, random walkers are injected and whole paths of individual walkers are removed at specified rates. We identify several distinct time scales that emerge from the system dynamics and can exceed the average axonal lifetime by orders of magnitude. In the dynamical steady state, the position-dependent distribution of fascicle sizes obeys a scaling law. We discuss our findings in terms of an analytically tractable, effective model of fascicle dynamics.

PACS
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
05.40.Fb - Random walks and Levy flights.
87.19.lx - Development and growth.

© EPLA 2009