An in-depth discussion of tear gas.

Before I repost this Twitter thread in toto, I'd like to say a few things.  First, Zander is an old friend of mine (pushing 20 years at this point).  Second, while he might bill himself as "an amateur chemist," his scientific expertise has been helpful to me numerous times over the years, so I feel that I can vouch for his knowledge as well as his assessment of the situation.  I asked him if I could repost this research earlier and he gave his permission.  For clarity I've made minor edits to add punctuation.  I've also reposted the images he …

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Biological mechanism that controls regeneration in zebrafish isolated.

At the Duke University Medical Center, biologists have been working with zebrafish, a common aquarium fish with unusual properties, namely, they can regenerate damaged limbs and organs, including fully functional eyes and hearts. They can re-grow an entire fin in approximately two weeks' time assuming that the fish is otherwise healthy. As it turns out, very small pieces of RNA (ribonucleic acid, which is involved in the synthesis of proteins, as well as controlling the state of certain genes) control whether or not the regeneration mechanism is active or not. If a particular micro-RNA strand, designated miR-133, has a low …

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