Randomized trial shows no difference from sham control ...

Researchers have devised a way to produce chemicals used in medicine and agriculture for a fraction of the usual cost. Using oxygen as a reagent and copper as a catalyst to break organic molecules' ...

FAA regulations (14 CFR 91.211) require private pilots to use supplemental oxygen when flying above 12,500 feet MSL for over 30 minutes, continuously above 14,000 feet MSL, and for all occupants above ...

The original version of this story appeared in Quanta Magazine. Take a deep breath. A flow of air has rushed into your lungs, where the oxygen moves into your bloodstream, fueling metabolic fires in ...

Oxygen fills the air today, but for most of Earth’s early history it barely existed. Scientists say the atmosphere did not hold steady oxygen until about 2.33 billion years ago, during the Great ...

The most widely accepted scientific explanation for the arrival of all complex life on Earth has had an unsolved mystery at its heart. According to the theory, all plants, animals and fungi, known ...

Researchers mapped enzyme sequences from several thousand modern species onto an evolutionary tree of life. Their findings suggest that, shortly after cyanobacteria evolved the ability to produce ...