The federal judge denied a Democratic lawmaker’s request for an emergency hearing on the closure, which began on Tuesday.

Scientists have discovered a powerful gene-targeting system in viruses. Billions of years old, VIPR seems to predate CRISPR and may be even more effective.

A former superintendent in Joplin, Mo., is trying to apply what he learned to other shattered districts — and reckoning with the toll of the disaster on his own life.