Diffusive transport in the presence of stochastically gated absorption
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Published version
Author(s)
Bressloff, Paul C
Karamched, Bhargav R
Lawley, Sean D
Levien, Ethan
Type
Journal Article
Abstract
We analyze a population of Brownian particles moving in a spatially uniform environment with stochastically gated absorption. The state of the environment at time
t
is represented by a discrete stochastic variable
k
(
t
)
∈
{
0
,
1
}
such that the rate of absorption is
γ
[
1
−
k
(
t
)
]
, with
γ
a positive constant. The variable
k
(
t
)
evolves according to a two-state Markov chain. We focus on how stochastic gating affects the attenuation of particle absorption with distance from a localized source in a one-dimensional domain. In the static case (no gating), the steady-state attenuation is given by an exponential with length constant
√
D
/
γ
, where
D
is the diffusivity. We show that gating leads to slower, nonexponential attenuation. We also explore statistical correlations between particles due to the fact that they all diffuse in the same switching environment. Such correlations can be determined in terms of moments of the solution to a corresponding stochastic Fokker-Planck equation.
t
is represented by a discrete stochastic variable
k
(
t
)
∈
{
0
,
1
}
such that the rate of absorption is
γ
[
1
−
k
(
t
)
]
, with
γ
a positive constant. The variable
k
(
t
)
evolves according to a two-state Markov chain. We focus on how stochastic gating affects the attenuation of particle absorption with distance from a localized source in a one-dimensional domain. In the static case (no gating), the steady-state attenuation is given by an exponential with length constant
√
D
/
γ
, where
D
is the diffusivity. We show that gating leads to slower, nonexponential attenuation. We also explore statistical correlations between particles due to the fact that they all diffuse in the same switching environment. Such correlations can be determined in terms of moments of the solution to a corresponding stochastic Fokker-Planck equation.
Date Issued
2017-08
Date Acceptance
2017-08-01
Citation
Physical Review E, 2017, 96 (2)
ISSN
2470-0045
Publisher
American Physical Society (APS)
Journal / Book Title
Physical Review E
Volume
96
Issue
2
Copyright Statement
©2017 American Physical Society
Identifier
http://dx.doi.org/10.1103/physreve.96.022102
Publication Status
Published
Article Number
022102
Date Publish Online
2017-08-01