ESPCI web site
PMMH’s weekly seminar is held every Friday at 11 am (map)
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France
Tel : (33) 1 40 79 45 22
Séminaire PMMH - Carine Douarche (LPS, Univ. Paris-Sud)
Bacteria self-assemblies lead to hydrodynamic instabilities
The mechanisms of the bacterial motility and chemotaxis are now quite well known at the single cell level ; however the way a whole cell population moves at a macroscopic scale still raises some fundamental questions. The study of the behavior of a population of Escherichia coli in oxygen gradients in the bulk of solutions shows that bacteria are able to adapt their motility and exhibit a collective behavior to self-assemble and form patterns. When subjected to gravity, these patterns become unstable and can be studied as Rayleigh-Taylor instabilities. In the same manner, when observing the morphogenesis of Bacillus subtilis floating biofilms, we detect some kinds of bacteria self-assemblies at the liquid-air interface that further undergo a bioconvection process. Thus, the presence of the bacteria in the solution locally modifies the properties of the environment that in turn act on the cells behavior. This interplay between the population of bacteria and the heterogeneities of the environment play an important role in conditioning the biofilm development as well as its structure.
The audience is composed of people with rather heterogeneous backgrounds including specialists in solids, fluids, granular flows, statistical physics... so the idea is to keep your talk understandable by people not necessarily working in your field... The seminar time slot runs from 11am to noon so the best is to make the talk last around 45 minutes to leave some time for discussion.
- Séminaires ESPCI-ENS de biophysique
- Séminaires du Département de Physique de l’ENS
- Séminaires du Laboratoire d’Hydrodynamique de l’X
- Séminaire de Mécanique d’Orsay (page web FAST)
- Séminaire de Mécanique d’Orsay (page web LIMSI)
- Séminaire de Mécanique des Fluides de l’Institut Jean le Rond d’Alembert
- Séminaires du laboratoire MSC, Paris VII
- Séminaires Gulliver
Link to cofee seminar (internal, every Thursday)
