Scientists now use AI to see blood clotting as it happens, without invasive procedures, using a new type of microscope.

His head and arms go in and out of the frame. Motion-tracking edits are the simplest way to keep the picture focused on his head and body, cropped to fill up the entire screen. Colbert himself ...

In one motion, rotate palm away from body and press the kettlebell overhead until right arm is straight and bicep is by ears. Reverse motion and lower weight to start. That's 1 rep. Complete 15 ...