Persistent random walk of cells involving anomalous effects and random death / Fedotov Sergei,Tan Abby,Zubarev Andrey // PHYSICAL REVIEW E. - 2015. - V. 91, l. 4.

ISSN/EISSN:
1539-3755 / 1550-2376
Type:
Article
Abstract:
The purpose of this paper is to implement a random death process into a persistent random walk model which produces sub-ballistic superdiffusion (Levy walk). We develop a stochastic two-velocity jump model of cell motility for which the switching rate depends upon the time which the cell has spent moving in one direction. It is assumed that the switching rate is a decreasing function of residence (running) time. This assumption leads to the power law for the velocity switching time distribution. This describes the anomalous persistence of cell motility: the longer the cell moves in one direction, the smaller the switching probability to another direction becomes. We derive master equations for the cell densities with the generalized switching terms involving the tempered fractional material derivatives. We show that the random death of cells has an important implication for the transport process through tempering of the superdiffusive process. In the long-time limit we write stationary master equations in terms of exponentially truncated fractional derivatives in which the rate of death plays the role of tempering of a Levy jump distribution. We find the upper and lower bounds for the stationary profiles corresponding to the ballistic transport and diffusion with the death-rate-dependent diffusion coefficient. Monte Carlo simulations confirm these bounds.
Author keywords:
REACTION-TRANSPORT SYSTEMS; TIME RANDOM-WALKS; FRACTIONAL DIFFUSION; RANDOM MOTION; MIGRATION; CHEMOTAXIS; EQUATION; MODELS; VELOCITIES; MOVEMENT
DOI:
10.1103/PhysRevE.91.042124
Web of Science ID:
ISI:000353142000003
Соавторы в МНС:
Другие поля
Поле Значение
Month APR 20
Publisher AMER PHYSICAL SOC
Address ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
Language English
Article-Number 042124
EISSN 1550-2376
Keywords-Plus REACTION-TRANSPORT SYSTEMS; TIME RANDOM-WALKS; FRACTIONAL DIFFUSION; RANDOM MOTION; MIGRATION; CHEMOTAXIS; EQUATION; MODELS; VELOCITIES; MOVEMENT
Research-Areas Physics
Web-of-Science-Categories Physics, Fluids \& Plasmas; Physics, Mathematical
Funding-Acknowledgement EPSRC {[}EP/J019526/1]
Funding-Text This work was funded by EPSRC Grant No. EP/J019526/1 `Anomalous reaction-transport equations'. The authors thank Nickolay Korabel and Steven Falconer for very useful discussions.
Number-of-Cited-References 65
Usage-Count-Since-2013 10
Journal-ISO Phys. Rev. E
Doc-Delivery-Number CG2YL