Anomalous Diffusion
Encyclopedia
Anomalous diffusion is a term used to describe a diffusion
process with a non-linear relationship to time, in contrast to a typical diffusion process, in which the mean squared displacement (msd), σr2, of a particle is a linear function of time.
Diffusion is often described by a power law, σr2 ~ Dtα, where D is the diffusion coefficient and t is the elapsed time. In a typical diffusion process, α = 1. If α > 1, the phenomenon is called super-diffusion. Super-diffusion can be the result of active cellular transport processes. If α < 1, the particle undergoes sub-diffusion
. Sub diffusion has been proposed as a measure of macromolecular crowding in the cytoplasm
.
Diffusion
Molecular diffusion, often called simply diffusion, is the thermal motion of all particles at temperatures above absolute zero. The rate of this movement is a function of temperature, viscosity of the fluid and the size of the particles...
process with a non-linear relationship to time, in contrast to a typical diffusion process, in which the mean squared displacement (msd), σr2, of a particle is a linear function of time.
Diffusion is often described by a power law, σr2 ~ Dtα, where D is the diffusion coefficient and t is the elapsed time. In a typical diffusion process, α = 1. If α > 1, the phenomenon is called super-diffusion. Super-diffusion can be the result of active cellular transport processes. If α < 1, the particle undergoes sub-diffusion
Diffusion
Molecular diffusion, often called simply diffusion, is the thermal motion of all particles at temperatures above absolute zero. The rate of this movement is a function of temperature, viscosity of the fluid and the size of the particles...
. Sub diffusion has been proposed as a measure of macromolecular crowding in the cytoplasm
Cytoplasm
The cytoplasm is a small gel-like substance residing between the cell membrane holding all the cell's internal sub-structures , except for the nucleus. All the contents of the cells of prokaryote organisms are contained within the cytoplasm...
.
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