Granular gases are convenient model systems to investigate the statistical physics of nonequilibrium systems. In the literature, one finds numerous theoretical predictions, but only few experiments. We study a weakly excited dilute gas of rods, confined in a cuboid container in microgravity during a suborbital rocket flight. With respect to a gas of spherical grains at comparable filling fraction, the mean free path is considerably reduced. This guarantees a dominance of grain-grain collisions over grain-wall collisions. No clustering was observed, unlike in similar experiments with spherical grains. Rod positions and orientations were determined and tracked. Translational and rotational velocity distributions are non-Gaussian. Equipartition of kinetic energy between translations and rotations is violated.

Self-organization in cells often manifests itself in oscillations and waves. Here, we address deformation waves in protoplasmic droplets of the plasmodial slime mold Physarum polycephalum by modelling and experiments. In particular, we extend a one-dimensional model that considered the cell as an poroelastic medium, where active tension caused mechanochemical waves that were regulated by an

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