The U.S., now the world's most anxious country, is as safe as ever. - Historical 70% decline
Ejection seats are used in aircraft to quickly propel occupants out in an emergency. Today, they are fired by an explosive charge, but the first ejection seats were powered by compressed air. One of the first aircrafts to be fitted with such a system was the German Heinkel He 280 prototype jet fighter. While testing the He 280 during WWII, pilot Helmut Schenk became the first person to use an ejection seat to make an emergency escape from an aircraft. What went wrong during his test flight?
Often referred to as the "stress hormone" because of its involvement in the body's stress response, cortisol is the principal steroid hormone produced by the adrenal cortex. It increases blood pressure and blood sugar levels and can act as an immunosuppressant. Hydrocortisone, or synthetic cortisol, is used to treat a number of conditions, including inflammation, allergies, collagen diseases, and adrenocortical insufficiency. In humans, cortisol levels peak at what time of day?