Ask Chemistry

Permanent ink from urethane, 99% IPA, and pigment?

I’m an artist and I started working with recycled plastic bottles as a material recently. I want to paint the plastic and retain its transparency, but acrylic paint won’t stick without priming and generally looks bad. Permanent markers are good, but they leave streaks over large swathes of color and are expensive. I want to […]

Ask Health Medical

Why aren’t lung machines / ECMO widely used for COVID-19?

I am not a doctor but I have read quite a bit on how COVID-19 affects the body. The ability of a critically afflicted patient to efficiently exchange oxygen drops off a cliff as the lungs fill with a slimy fluid that clogs the alveoli, as the body tries to combat the viral cell damage. […]

Mastering Development

LibGDX / Box2D: How to keep track of active Contacts between bodies?

I’m making a 2D (side view) car game with LibGDX using Box2D. The car has a front wheel and a rear wheel and it’s "AWD". I would like to render a dust effect to each point where a wheel touches the ground when the player is "burning rubber". To do this, my plan was to […]

Development Linux Ubuntu

How to remove snap from Ubuntu 18.04 (before and after install)?

I know that snap is a new way to go for ubuntu strategy, but I am having many problems with snap approach. Problems encountered, up to now: 1) take 5x more time to mount a partition (lots of disk activity) 2) many applications have permission problems, lets take gimp as an example. 2.1) Gimp take […]

Bitcoin Cryptocurrency Development

What would the effect of a very long bear market be on the Bitcoin economy?

I don’t mean to be a doomsday prophet or spread FUD, but I need to know if Bitcoin (or any PoW coin) investors should be concerned about the following scenario: Assume Bitcoin goes in a very long bearish market which makes mining unprofitable and cause many mining companies/individuals to go bankrupt. From my understanding, the […]