As Omicron rips thru the world, we know one simple thing that can really help. PROPERLY WORN MASKS.
Masks work.
But practically, with cloth masks, surgical masks, and"N95"s around, how does one choose? Can we reuse masks? How?
With @cspramesh's help a long🧵(1/n)
RT if helpful! The most important thing is a proper fit. The best “N95” mask that doesn't cover the nose & mouth and seal tightly against the face without gaps is useless! Unfortunately, many people take the mask off their nose if no one's watching, even worse, think it's a chin ornament! (2/n)

Now that everyone finally knows about #javelin throwing thanks to @Neeraj_chopra1's phenomenal gold medal at the Olympics, it's time to look at some delightful #Physics trivia and history behind this beautiful sport! A lazy Sunday thread on the Javelin throw! #scicomm (1/n) Observation 1: High school physics says "for max range, a projectile should be launched at a 45 degree angle". That's true only for launch & target at the same height! Here, launch ~2m above ground, target at ground + LOTS of aerodynamics -> optimal angle is ~36 degrees! (2/n)

As promised a detailed thread on washing surgical masks:
I've HAND washed several surgical, and "cloth with polymer interlayer" masks to test their particle filtration efficiency at 0.3um. There are both high quality and cheaper masks, sourced from India and Bangladesh. (1/n) New masks have hydrophobic outer layer (see water balling up?) Rub a bar of detergent and it gets wet. Scrub 2 min, rinse well. Hang to dry. First few washes, will recover hydrophobic nature, after lots of scrubbing it gets rough. (2/n)