Competition between growth and shear stress drives intermittency in preferential flow paths in porous medium biofilms.

Bacteria in porous media, such as soils, aquifers, and filters, often form surface-attached communities known as biofilms. Biofilms are affected by fluid flow through the porous medium, for example, for nutrient supply, and they, in turn, affect the flow. A striking example of this interplay is the strong intermittency in flow that can occur when biofilms nearly clog the porous medium.

Capillary and viscous fracturing during drainage in porous media.

Detailed understanding of the couplings between fluid flow and solid deformation in porous media is crucial for the development of novel technologies relating to a wide range of geological and biological processes. A particularly challenging phenomenon that emerges from these couplings is the transition from fluid invasion to fracturing during multiphase flow. Previous studies have shown that this transition is highly sensitive to fluid flow rate, capillarity, and the structural properties of the porous medium.

Intrathoracic fracture-dislocation of the humeral head: a case report.

Fracture-dislocation of the humeral head into the thoracic cavity is a rare injury. We present one such case in a 70-year-old woman. She presented with a 4-part fracture-dislocation of the proximal humerus, with displacement of the humeral head into the thoracic cavity.