title: Diffusion-reaction in branched structures: theory and application to the lung acinus.
abstract: An exact "branch by branch" calculation of the diffusional flux is proposed for partially absorbed random walks on arbitrary tree structures. In the particular case of symmetric trees, an explicit analytical expression is found which is valid whatever the size of the tree. Its application to the respiratory phenomena in pulmonary acini gives an analytical description of the crossover regime governing the human lung efficiency.
authors.affiliation: Laboratoire de Physique de la Matière Condensée, C.N.R.S. Ecole Polytechnique, 91128 Palaiseau, France. denis.grebenkov@polytechnique.fr
authors.forename: D S
authors.initials: DS
authors.lastname: Grebenkov
authors.forename: M
authors.initials: M
authors.lastname: Filoche
authors.forename: B
authors.initials: B
authors.lastname: Sapoval
authors.forename: M
authors.initials: M
authors.lastname: Felici
mesh_terms: D000818:Animals; D003198:Computer Simulation; D004058:Diffusion; D006801:Humans; D008954:Models, Biological; D015233:Models, Statistical; D010100:Oxygen / Q000737:chemistry* / Q000378:metabolism*; D011650:Pulmonary Alveoli / Q000737:chemistry* / Q000378:metabolism*; D011659:Pulmonary Gas Exchange / Q000502:physiology*
chemical_list: D010100:Oxygen