FAYETTEVILLE, Ark. — Microplastics, tiny plastic particles found in everyday products from face wash to toothpaste, are an emerging threat to health and ecology, prompting a research team to identify what keeps them trapped in stream ecosystems.

Chemists have confirmed a 67-year-old theory about vitamin B1 by stabilizing a reactive molecule in water — a feat long thought impossible. The discovery not only solves a biochemical mystery, but also opens the door to greener, more efficient ways of making pharmaceuticals.

Saying one thing while feeling another is part of being human, but bottling up emotions can have serious psychological consequences like anxiety or panic attacks. To help health care providers tell the difference, a team led by scientists at Penn State has created a stretchable, rechargeable sticker that can detect real emotions — by measuring things like skin temperature and heart rate — even when users put on a brave face.