Rendez-vous de l'UFR de Physique
-A +A
23.11.2018
Amphithéâtre Pierre Gilles de Gennes - Bâtiment Condorcet

Séminaire Général de Physique - avec Anke Lindner, E-coli bacteria in interaction with flows and boundaries

Le troisième séminaire général de la saison 2018-2019 a lieu le vendredi 23 novembre 10h
(café-croissants à partir de 9h45)


Nous recevrons :
Anke Lindner (PMMH, ESPCI et UPD)

Titre : E-coli bacteria in interaction with flows and boundaries

Résumé : Active fluids consist of self-propelled particles (as bacteria
or artificial microswimmers) and display properties that differ strongly
from their passive counterparts. Unique physical phenomena, as enhanced
Brownian diffusivity, viscosity reduction, active transport and mixing
or the extraction of work from chaotic motion, result from the activity
of the particles, locally injecting energy into the system. The presence
of living and cooperative species may also induce collective motion and
organization at the mesoscopic or macroscopic level impacting the
constitutive relationships in the
semi-dilute or dense regimes.

Individual bacteria transported in viscous flows, show complex
interactions with flows and bounding surfaces resulting from their
complex shape as well as their activity. Understanding these transport
dynamics is crucial, as they impact soil contamination, transport in
biological conducts or catheters, and constitute thus a serious health
thread.

Here we investigate the trajectories of individual E-coli bacteria in
confined geometries under flow, using microfluidic model systems will in
bulk flows as well as close to surfaces using a novel Lagrangian 3D
tracking method. Combining experimental observations and modelling we
elucidate the origin of upstream swimming, lateral drift or persistent
transport along corners. The understanding gained can be used to design
channel geometries to guide bacteria towards specific locations or to
prevent upstream contamination.

References :
Darnige et al. Lagragian 3D tracking of fluorescent microscopic objects
in motion, Review of Scientific Instruments 88, 055106 (2017)
Mathijssen et al. Oscillatory surface rheotaxis of swimming E. coli
bacteria, arXiv:1803.01743
Figueroa-Morales et al., Living on the edge: transfer and traffic of E.
coli in a confined flow, Soft Matter, 2015,11, 6284-6293


Rendez-vous pour le café/croissants à partir de 9h45 :
Bâtiment Condorcet - espace de convivialité du niveau -1 (en bas de
l'escalier à vis)
10 rue Alice Domon et Léonie Duquet
Université Paris Diderot - UFR de Physique Paris 13ème.

L'équipe du séminaire Général : C. Benoit, E. Boulat, S. Chaty, M.
Durand, F. Gallet.

 

A noter : dates des prochains séminaires :

- 21 décembre : Anthony Boccaletti (LESIA, Observatoire de Meudon et UPD) (Sous réserve)
- 25 janvier 2019 : Olivier Darrigol (SPHERE, UPD)
- 22 février
- 22 mars : Olivier Pouliquen (IUSTI, Marseille)
- 19 avril : Hervé Cottin (LISA, UPEC)
- 24 mai
- 21 juin


L'équipe du séminaire Général : C. Benoit, E. Boulat, S. Chaty, M.
Durand, F. Gallet.
 

 

 

 

Archives des anciens séminaires

 

 

 

 

 

Thématique >
Nature >