Bead Counter Mechanism

BeadCounter-web

BeadCounter_SwitchDetail-web

Renderings of a lasercut bead counter. The ratchet-like cog rotates, collecting a single bead from the tube above. The bead moves to the side and drops through a hole. As the cog rotates, its prongs close a small switch, allowing for automated counting via an Arduino.

Video Of Virus Entering Cell

Video (yes, video: recorded with two cameras and converted to the image we see here) of a virus attempting to enter a cell. A complex problem, likened in the article to trying to film something the size and speed of a hummingbird flying around in a space as large as a backyard.

Via Princeton