Smiley sensor works like a temporary tattoo to detect disease.

A medical sensor, that adheres to the skin like a temporary tattoo could make it easier for doctors to detect metabolic problems in patients as well as help coaches to fine-tune athletes’ training routines, say researchers at the Department of Physical & Environ mental Sciences at the University of Toronto, Scarborough, Canada (UTSC). The entire sensor was designed as a thin, flexible package shaped like a smiley face.