Audrey Carlson, reporting for NPR:
A big reason the Achilles is such a foot-dragger at getting better is that the tendon tissue we have as adults is basically the same as we had when we were teenagers. That finding was published earlier this week in The FASEB Journal. But how the researchers figured that out is every bit as interesting as the result. The scientists used fallout from nuclear bomb tests as biological tracers.
I have yet to find a scientific use of stable isotopes that I don’t admire.