Probing microscopic origins of confined subdiffusion by first-passage observables

@article{citeulike:2842523, abstract = {Subdiffusive motion of tracer particles in complex crowded environments, such as biological cells, has been shown to be widespread. This deviation from Brownian motion is usually characterized by a sublinear time dependence of the mean square displacement (MSD). However, subdiffusive behavior can stem from different microscopic scenarios that cannot be identified solely by the MSD data. In this article we present a theoretical framework that permits the analytical calculation of first-passage observables (mean first-passage times, splitting probabilities, and occupation times distributions) in disordered media in any dimensions. This analysis is applied to two representative microscopic models of subdiffusion: continuous-time random walks with heavy tailed waiting times and diffusion on fractals. Our results show that first-passage observables provide tools to unambiguously discriminate between the two possible microscopic scenarios of subdiffusion. Moreover, we suggest experiments based on first-passage observables that could help in determining the origin of subdiffusion in complex media, such as living cells, and discuss the implications of anomalous transport to reaction kinetics in cells. 10.1073/pnas.0712158105}, author = {Condamin, S. and Tejedor, V. and Voituriez, R. and Benichou, O. and Klafter, J. }, citeulike-article-id = {2842523}, doi = {10.1073/pnas.0712158105}, journal = {Proceedings of the National Academy of Sciences}, keywords = {fractals, random\_walk, subdiffusion}, month = {April}, number = {15}, pages = {5675--5680}, posted-at = {2008-05-28 20:04:36}, priority = {2}, title = {Probing microscopic origins of confined subdiffusion by first-passage observables}, url = {http://dx.doi.org/10.1073/pnas.0712158105}, volume = {105}, year = {2008} }

TY - JOUR ID - citeulike:2842523 L3 - citeulike-article-id:2842523 TI - Probing microscopic origins of confined subdiffusion by first-passage observables JF - Proceedings of the National Academy of Sciences VL - 105 IS - 15 SP - 5675 EP - 5680 N2 - Subdiffusive motion of tracer particles in complex crowded environments, such as biological cells, has been shown to be widespread. This deviation from Brownian motion is usually characterized by a sublinear time dependence of the mean square displacement (MSD). However, subdiffusive behavior can stem from different microscopic scenarios that cannot be identified solely by the MSD data. In this article we present a theoretical framework that permits the analytical calculation of first-passage observables (mean first-passage times, splitting probabilities, and occupation times distributions) in disordered media in any dimensions. This analysis is applied to two representative microscopic models of subdiffusion: continuous-time random walks with heavy tailed waiting times and diffusion on fractals. Our results show that first-passage observables provide tools to unambiguously discriminate between the two possible microscopic scenarios of subdiffusion. Moreover, we suggest experiments based on first-passage observables that could help in determining the origin of subdiffusion in complex media, such as living cells, and discuss the implications of anomalous transport to reaction kinetics in cells. 10.1073/pnas.0712158105 KW - fractals KW - random_walk KW - subdiffusion AU - Condamin, S AU - Tejedor, V AU - Voituriez, R AU - Benichou, O AU - Klafter, J PY - 2008/04/15/ UR - http://dx.doi.org/10.1073/pnas.0712158105 ER -