You can get a brighter smile with a number of different whitening products and techniques available at home or at a dentist’s office. They vary in effectiveness (and price), but none of them provide ...

It’s hard to believe that the first blue LED didn’t arrive until 1993. They look simple, but looks are deceiving (Fig. 1). 1. Image showing a blue InGaN-based LED with gold wire contacts (0.4 × 0.4 mm ...