Researchers at Harvard and Brigham and Women’s Hospital found that transplanted hearts shift toward the biological age of their recipients. Old hearts get younger in young bodies, and young hearts get older in older ones. Which is nuts. Today, we're launching a partnership with our friends @runwayml to, among other things, bring one of the stories from each week's Dose to life in video. I'm not great at it yet, but not bad for a few prompts! And I'm excited to get better. I have zero talent in…