Hair loss is undesirable for many men -- and women -- because one's hairstyle is often closely tied to their self-confidence. And while some people embrace it, others wish they could regrow their lost strands. Now, researchers have used artificial intelligence (AI) to predict compounds that could neutralize baldness-causing reactive oxygen species in the scalp. Using the best candidate, they constructed a proof-of-concept microneedle patch and effectively regenerated hair on mice.