An environmental engineer, he invented a biological method to remove nitrogen and phosphorous from wastewater, an advance that transformed the industry worldwide.

A mouse study highlights the role of acetylcholine in behavioral flexibility, offering new insight into the brain mechanisms involved in addiction and obsessive compulsive disorder.

A surprising FDA reversal on Moderna’s mRNA flu vaccine, early promise from a universal inhaled vaccine, and a desert fossil find that is reshaping spinosaurid history.

This crossword is inspired by the most recent issue of Scientific American. Read it here. Print readers, check your answers by selecting “Assist” above and then “Reveal Grid” or by selecting “Print” ...