Every weekday, NPR's best political reporters are there to explain the big news coming out of Washington and the campaign trail. They don't just tell you what happened. They tell you why it matters.

Protein design (or protein engineering) is a technique by which proteins with enhanced or novel functional properties are created. Proteins can be engineered by rational design, which typically uses ...

The fully automated, short-range Avenger air defense system is the Army's premier shoot-on-the-move air defense weapon. It is a lightweight, highly mobile, easily transportable surface-to-air missile ...