Accueil >
Production scientifique
Mécanique statistique des systèmes désordonnés, en particulier inspirés par des systèmes à l'interface avec la biologie
(9) Production(s) de l'année 2018
|
|
Role of spatial heterogeneity in the collective dynamics of cilia beating in a minimal one-dimensional model
Auteur(s): Dey S., Massiera G., Pitard E.
(Article) Publié:
Physical Review E: Statistical, Nonlinear, And Soft Matter Physics, vol. 97 p.012403 (2018)
Texte intégral en Openaccess :
Ref HAL: hal-01735760_v1
DOI: 10.1103/PhysRevE.97.012403
WoS: WOS:000423129000005
Exporter : BibTex | endNote
2 Citations
Résumé: Cilia are elastic hairlike protuberances of the cell membrane found in various unicellular organisms and in several tissues of most living organisms. In some tissues such as the airway tissues of the lung, the coordinated beating of cilia induce a fluid flow of crucial importance as it allows the continuous cleaning of our bronchia, known as mucociliary clearance. While most of the models addressing the question of collective dynamics and metachronal wave consider homogeneous carpets of cilia, experimental observations rather show that cilia clusters are heterogeneously distributed over the tissue surface. The purpose of this paper is to investigate the role of spatial heterogeneity on the coherent beating of cilia using a very simple one dimensional model for cilia known as the rower model. We systematically study systems consisting of a few rowers to hundreds of rowers and we investigate the conditions for the emergence of collective beating. When considering a small number of rowers, a phase drift occurs, hence a bifurcation in beating frequency is observed as the distance between rowers clusters is changed. In the case of many rowers, a distribution of frequencies is observed. We found in particular the pattern of the patchy structure that shows the best robustness in collective beating behavior, as the density of cilia is varied over a wide range.
|
|
|
Activity statistics in a colloidal glass former: experimental evidence for a dynamical transition
Auteur(s): Abou Bérengère, Colin Rémy, Lecomte Vivien, Pitard E., van Wijland Frédéric
(Article) Publié:
The Journal Of Chemical Physics, vol. 148 p.164502 (2018)
Texte intégral en Openaccess :
Ref HAL: hal-01517340_v1
Ref Arxiv: 1705.00855
DOI: 10.1063/1.5006924
WoS: 000431291900023
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
5 Citations
Résumé: In a dense colloidal suspension at a volume fraction slightly lower than that of its glass transition, we follow the trajectories of an assembly of tracers over a large time window. We define a local activity, which quantifies the local tendency of the system to rearrange. We determine the statistics of the time and space integrated activity, and we argue that it develops a low activity tail that comes on a par with the onset of glassy behavior and heterogeneous dynamics. These rare events may be interpreted as the reflection of an underlying dynamic phase transition.
Commentaires: 10 pages, 15 figures
|