MARMOTTANT , Philippe

Drought poses a significant threat to forest survival worldwide by potentially generating air bubbles that obstruct sap transport within plants' hydraulic systems. However, the detailed mechanism of air entry and propagation at the scale of the veins remains elusive. Building upon a biomimetic model of leaf which we developed, we propose a...

Plants move, and not only under the action of the wind or during growth. Although they lack muscle, some have developed mechanisms to generate surprisingly fast movements, with speeds (about 10 m/s) and accelerations (thousands of g) that compete and even surpass those encountered in the animal kingdom.

We study the elasto-plastic behaviour of materials made of individual (discrete) objects, such as a liquid foam made of bubbles. The evolution of positions and mutual arrangements of individual objects is taken into account through statistical quantities, such as the elastic strain of the structure, the yield strain and the yield function. The...

Dépourvues de muscles, certaines plantes mettent en œuvre des mouvements dont la fulgurance est comparable à celle des animaux. Nous montrons dans cet article que beaucoup de ces mouvements, nécessités par la reproduction ou la nutrition, ont la même base physique : une instabilité mécanique qui libère de l'énergie élastique stockée. Deux...

National audience

Cell apical constriction driven by actomyosin contraction forces is a conserved mechanism during tissue folding in embryo development. While much is now understood of the molecular mechanism responsible for apical constriction and of the tissue-scale integration of the ensuing in-plane deformations, it is still not clear if apical actomyosin...