It's not hail, however – that is typically formed in thunderstorms. Rather, the small, soft pellets are what is known as graupel, when supercooled water droplets high in the atmosphere freeze into a ...

Engineers use feedback loops — typically negative feedback is more useful, but positive feedback is needed for oscillators.

Blackington, a longtime occupational therapist, saw this disconnect up close for over 15 years. Her answer is Dovetail, a ...