Somewhat more formally, for a set Ï of properties and relations, a Ï-representation of some structure X is a structure Y that is the image of X under a s homomorphism that preserves Ï. The label representation is sometimes also applied to the homomorphism itself.
Melanoma. This cancer begins in the melanocytes, the cells that provide the skinâs color. Melanoma is one of the deadliest forms of skin cancer because it can spread rapidly inside the body. Approximately one American dies from melanoma every hour.
Melasma Overview. Patches of melasma are darker than other areas of skin because they have more pigment. The cells that produce pigment in the skin are called melanocytes. Ultraviolet radiation, or UV rays, from the sun stimulate melanocytes to produce pigment.