ESPCI web site
Le séminaire hebdomadaire du laboratoire PMMH a lieu tous les vendredis à 11h, au premier étage Barre Cassan, campus Jussieu (plan).
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 - Lorraine Montel (UPMC)
Emulsion droplets as a model biomimetic system
Emulsion droplets recapitulate the deformability and surface fluidity of biological objects, in a simpler and tunable fashion. Thus, they can be used as a model biomimetic system to study cell-cell interactions. During this talk, I will demonstrate this use in two different systems : the study of phagocytosis, and the study of the role adhesion plays in tissues.
During phagocytosis, immune cells identify, internalize and digest foreign objects or dying cells, a process essential for immunity, but also for the homeostasis of tissues. Phagocytic cells are able to internalize objects bigger than themselves, yet, how the size of their target impacts their ability to phagocyte remains a controversial question. Using polydisperse emulsions and a new automated analysis method, we could show that the phagocytes do not select the size of their targets. Instead, they are limited in the total surface they can engulf, and can thus internalize less of the bigger objets. Moreover, this surface limitation is common to diverse types of cells, of ligands and of objects across all ranges of sizes.
During morphogenesis, cell differenciate and reorganize acquire their shape and function. In addition to biological cues, the mechanical properties of cells and their interactions are essential to this process. Yet, in biological systems, it is challenging to isolate the role of one parameter. Adhesive emulsion droplets can also be used as a model system to question the role of adhesion in tissue mechanics, without the interference of biochemical signalling, feedback loops and active processes. We sheared an adhesive emulsion in a microfluidic constriction, and observed with confocal microscopy how adhesion impacted the shape of droplets and their rearrangements. In dynamics, we found that T1 rearrangement events occur more slowly and at much higher deformation in the presence of adhesion. At a global scale, the topology of rearrangements is not impacted, however, the adhesion creates a global polarization of the deformation in the direction of the flow.
Séminaires (4)
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Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…) -
Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…) -
Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…) -
Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…)
Instructions générales pour les conférenciers
Le public du séminaire est très hétérogène (rien qu’au PMMH nous travaillons sur des thématiques très diverses, mécanique des fluides, des milieux granulaires, des solides, physique statistique, physique du mouillage, micro-fluidique, biophysique,...) l’objectif est donc de ne pas faire un séminaire trop spécialiste : au moins la première moitié du séminaire à un niveau accessible pour celui qui ne connaît rien sur le sujet.
Le séminaire a lieu à 11h. rendez-vous 15 minutes avant pour installer et tester la projection.
Le séminaire dure environ 45 minutes pour laisser un peu de temps pour discuter à la fin.
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- 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
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