nephrosis neÂ·phroÂ·sis (nÉ-frÅ'sÄ­s) n. pl. neÂ·phroÂ·ses (-sÄz) Disease of the kidneys marked by degeneration of renal tubular epithelium. See nephrotic syndrome.
Ultraviolet light is a form of radiation which is not visible to the human eye. It's in an invisible part of the electromagnetic spectrum. Radiated energy, or radiation, is given off by many objects: a light bulb, a crackling fire, and stars are some examples of objects which emit radiation. The type of radiation being emitted depends on the temperature of the object.
UV-A light is often referred to colloquially as black light. This is the most visible type of UV light, because it has the longest wavelength. You can buy UV-A black light bulbs at most stores. They release bluish-purple light and are used in concerts and entertainment because certain colors appear to glow beneath them.