“Using an at-home mask is like going to the gym,” says Shereene Idriss, MD, a board-certified dermatologist and founder of Idriss Dermatology in NYC. To truly see any skin care benefit, you need to ...

The function of an LED is to emit light when the device is forward biased within its operating range, and it’s known by most people that an LED can also operate as a photodiode. Perhaps some readers ...