Popular Science | HemCon Bandage: "Half of all deaths on the battlefield are due to uncontrollable bleeding. And though gauze is often no match for spurting wounds, the bloodthirsty HemCon Bandage is: It contains positively charged chitosan molecules, extracted from shrimp shells, that attract negatively charged red blood cells. As the cells are pulled into the bandage, they create a tight-fitting plug over the wound. 'You can have a hole in your heart and 60 seconds later it's sealed,' says HemCon inventor Kenton Gregory. The bandage made its debut in the 2003 Iraq war and was FDA-approved for nonprescription use in August. At $100 for a 4-by-4-inch square, it may sound expensive, but if the situation calls for it, we're guessing it'll seem like a serious bargain. "

The blood stops itself - a good example of an ideal solution.
tags: invention effect ideal solution control