Contact :
Matthieu Labousse
matthieu.labousse (arobase)
Tel : +33 (0) 1 40 79 45 97

Joshua McGraw
joshua.mcgraw (arobase)
Tel : +33 (0) 1 40 79 59 62


Gulliver seminars take place on Mondays at 11:30 AM in the F304 room, and typically last one hour including questions. The seminars are in English, and the scientific topics are mainly those studied in the laboratory.

Gulliver Seminar : Christian Wagner (Saarland University)

Lundi 26 juin de 11h30 à 12h30 - Bibliothèque PCT - F3.04

The physics of blood flow

Blood is a complex fluid composed of red and white cells suspended in a protein solution called plasma. At low shear rates, red blood cells form aggregates, which are broken up at high shear rates, resulting in pronounced shear thinning. Nevertheless, in most medical simulations, blood is treated as a Newtonian fluid comparable to water. However, thanks to recent advances in numerical simulation techniques and experimental methods, it is now possible to describe the flow of blood in terms of the physical properties of individual cells. Red blood cells can pass through capillaries smaller than their own diameter, thanks to their high deformability. This implies a strong interaction between fluid and structure that makes simulations costly and realistic simulations are limited to a few thousand cells. We will present in vitro, in vivo and in silico results of cells in different flow geometries. By directly comparing the observed shapes, we can estimate the mechanical constants of the cells. However, in many pathological situations, the cell properties are highly altered, and we have used our artificial intelligence-based recognition algorithm to develop a tool that can assess, for example, the quality of blood products.

Finally, we will show that a well-established nonspecific diagnostic test for inflammation, the erythrocyte sedimentation rate (ESR), can be physically described as a new class of fragile gel made of very soft, deformable objects. We find that sedimentation rate has a surprising functional relationship with interaction strength and propose new evaluation criteria for this test.


Seminars  (2)

General recommendations for the speakers

The audience is often heterogeneous - because of the wide range of scientific topics covered in the lab - so planning a talk for a broader audience would be preferred. The seminar is in English, and speakers are thus invited to prepare their slides in English.

The seminar starts at 11:30 AM. The speaker is asked to arrive in the lab at least 15 minutes in advance to set up their computer. The talks last typically 45 minutes, and are followed by a discussion time.