Letter from Lhasa: All about oxygen

by Cao Bin

LHASA, April 27 (Xinhua) -- While a person can only survive for a few minutes without oxygen, what happens when oxygen content in the air is only two-thirds of the normal level?

Hypoxia, a condition where the body doesn't receive enough oxygen, is a reality on the "roof of the world." In fact, as I write these words, I myself am using the oxygen supply system in my office to help me breathe.