Physics

Fractional rheology of living systems

This event is part of the Biophysics/Condensed Matter Seminar Series.

Cells are not only the elementary building block of living systems, but more interestingly they are active mechanical machines that, in contrast to amorphous materials, have the fascinating property to constantly remodel their structural organization to withstand forces and deformations and to promptly adapt to their mechanical environment. The rheology of living cells and tissues is nowadays considered as an important actor in the maintenance and recovery of cell homeostasis. Living cells and tissues can adopt a variety of rheological behaviors, from rhythms to apparently stochastic and scale invariant dynamics. In the 30 to 103 Hz range, the cytoskeleton (interconnected protein filament network) of living cells behaves as a viscoelastic soft glassy material with a power-law (fractional) rheology. In that frequency range, an indivisible relation exists between storage (real part) and loss (imaginary part) components of the complex shear modulus...