Cargando…
Intermediate scattering function of an anisotropic active Brownian particle
Various challenges are faced when animalcules such as bacteria, protozoa, algae, or sperms move autonomously in aqueous media at low Reynolds number. These active agents are subject to strong stochastic fluctuations, that compete with the directed motion. So far most studies consider the lowest orde...
Autores principales: | , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group
2016
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5378927/ https://www.ncbi.nlm.nih.gov/pubmed/27830719 http://dx.doi.org/10.1038/srep36702 |
_version_ | 1782519508758429696 |
---|---|
author | Kurzthaler, Christina Leitmann, Sebastian Franosch, Thomas |
author_facet | Kurzthaler, Christina Leitmann, Sebastian Franosch, Thomas |
author_sort | Kurzthaler, Christina |
collection | PubMed |
description | Various challenges are faced when animalcules such as bacteria, protozoa, algae, or sperms move autonomously in aqueous media at low Reynolds number. These active agents are subject to strong stochastic fluctuations, that compete with the directed motion. So far most studies consider the lowest order moments of the displacements only, while more general spatio-temporal information on the stochastic motion is provided in scattering experiments. Here we derive analytically exact expressions for the directly measurable intermediate scattering function for a mesoscopic model of a single, anisotropic active Brownian particle in three dimensions. The mean-square displacement and the non-Gaussian parameter of the stochastic process are obtained as derivatives of the intermediate scattering function. These display different temporal regimes dominated by effective diffusion and directed motion due to the interplay of translational and rotational diffusion which is rationalized within the theory. The most prominent feature of the intermediate scattering function is an oscillatory behavior at intermediate wavenumbers reflecting the persistent swimming motion, whereas at small length scales bare translational and at large length scales an enhanced effective diffusion emerges. We anticipate that our characterization of the motion of active agents will serve as a reference for more realistic models and experimental observations. |
format | Online Article Text |
id | pubmed-5378927 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2016 |
publisher | Nature Publishing Group |
record_format | MEDLINE/PubMed |
spelling | pubmed-53789272017-04-07 Intermediate scattering function of an anisotropic active Brownian particle Kurzthaler, Christina Leitmann, Sebastian Franosch, Thomas Sci Rep Article Various challenges are faced when animalcules such as bacteria, protozoa, algae, or sperms move autonomously in aqueous media at low Reynolds number. These active agents are subject to strong stochastic fluctuations, that compete with the directed motion. So far most studies consider the lowest order moments of the displacements only, while more general spatio-temporal information on the stochastic motion is provided in scattering experiments. Here we derive analytically exact expressions for the directly measurable intermediate scattering function for a mesoscopic model of a single, anisotropic active Brownian particle in three dimensions. The mean-square displacement and the non-Gaussian parameter of the stochastic process are obtained as derivatives of the intermediate scattering function. These display different temporal regimes dominated by effective diffusion and directed motion due to the interplay of translational and rotational diffusion which is rationalized within the theory. The most prominent feature of the intermediate scattering function is an oscillatory behavior at intermediate wavenumbers reflecting the persistent swimming motion, whereas at small length scales bare translational and at large length scales an enhanced effective diffusion emerges. We anticipate that our characterization of the motion of active agents will serve as a reference for more realistic models and experimental observations. Nature Publishing Group 2016-11-10 /pmc/articles/PMC5378927/ /pubmed/27830719 http://dx.doi.org/10.1038/srep36702 Text en Copyright © 2016, The Author(s) http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ |
spellingShingle | Article Kurzthaler, Christina Leitmann, Sebastian Franosch, Thomas Intermediate scattering function of an anisotropic active Brownian particle |
title | Intermediate scattering function of an anisotropic active Brownian particle |
title_full | Intermediate scattering function of an anisotropic active Brownian particle |
title_fullStr | Intermediate scattering function of an anisotropic active Brownian particle |
title_full_unstemmed | Intermediate scattering function of an anisotropic active Brownian particle |
title_short | Intermediate scattering function of an anisotropic active Brownian particle |
title_sort | intermediate scattering function of an anisotropic active brownian particle |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5378927/ https://www.ncbi.nlm.nih.gov/pubmed/27830719 http://dx.doi.org/10.1038/srep36702 |
work_keys_str_mv | AT kurzthalerchristina intermediatescatteringfunctionofananisotropicactivebrownianparticle AT leitmannsebastian intermediatescatteringfunctionofananisotropicactivebrownianparticle AT franoschthomas intermediatescatteringfunctionofananisotropicactivebrownianparticle |