The flow properties of suspensions of colloidal particles depart from simple Newtonian behaviour at high shear rate, high volume fraction, or when the colloidal particles interact. We study the mechanical properties of suspensions in such conditions, aiming at correlating them to their organization at the particle scale. When the suspension is concentrated enough, the suspension forms granulates: we study the mixing of a powder with a liquid and, in particular, the mechanisms at play in the granulates imbibition.
Protein levels are tightly regulated at various stages of gene expression. Activators can modify the affinity of RNA polymerase for specific promoters, while small non-coding RNAs may bind to mRNA, either facilitating RNase recruitment or binding to ribosome binding sites (RBS) to alter translation. Through single-molecule techniques, we investigate these fundamental biological processes and their roles in the regulation of gene expression.