Edema has many possible causes: 1  Prolonged standing or sitting, especially in hot weather, can cause excess fluid to accumulate in the feet, ankles and lower legs. 2  Tiny valves inside the veins of the legs can become weakened, causing a common problem called venous insufficiency.
Cars with nitrous-equipped engines can be identified by the purge of the delivery system that most drivers perform prior to reaching the starting line. A separate electrically operated valve is used to release air and gaseous nitrous oxide trapped in the delivery system.
Nitrous oxide (N2O) is simply a gas which you can breathe in. It has no color, smell, and doesnât irritate. It was discovered in 1772. âOn the day when the inflammation was the most troublesome, I breathed three large doses of nitrous oxide.