Seeing a fluid behaving like a solid. Researchers using a high-speed camera have captured the moments a fluid reacts like a solid, through a new method of fluid observation under pressurized conditions. They examined fluids that have a solid-like response to stress, a phenomenon called Discontinuous Shear Thickening (DST). This is when liquid abruptly thickens and becomes solid when disturbed. DST is being researched for engineering applications such as soft body armor, 'smart' speed bumps, and food production. Source 7x.