The Ghubar Arabs transformed the digit in several different ways, producing from that were more similar to the digits 4 or 3 than to 5. It was from those digits that Europeans finally came up with the modern 5. While the shape of the character for the digit 5 has an ascender in most modern typefaces, in typefaces with text figures the glyph usually has a descender, as, for example, in . On the seven-segment display of a calculator, it is represented by five segments at four successive turns from top to bottom, rotating counterclockwise first, then clockwise, and vice-versa. Science
The atomic number of boron. The number of appendages on most starfish, which exhibit pentamerism. The most destructive known hurricanes rate as Category 5 on the Saffir–Simpson hurricane wind scale. The most destructive known tornadoes rate an F-5 on the Fujita scale or EF-5 on the Enhanced Fujita scale. Astronomy
Messier object M5, a magnitude 7.0 globular cluster in the constellation Serpens. The New General Catalogue object NGC 5, a magnitude 13 spiral galaxy in the constellation Andromeda. The Roman numeral V stands for dwarfs (main sequence stars) in the Yerkes spectral classification scheme. The Roman numeral V (usually) stands for the fifth-discovered satellite of a planet or minor planet (e.g. Jupiter V). There are five Lagrangian points in a two-body system. Biology
There are generally considered to be five senses. The five basic tastes are sweet, salty, sour, bitter, and umami.
Hyperkeratosis is thickening of the stratum corneum (the outermost layer of the epidermis, or skin), often associated with the presence of an abnormal quantity of keratin, and also usually accompanied by an increase in the granular layer. As the corneum layer normally varies greatly in thickness in different sites, some experience is needed to assess minor degrees of hyperkeratosis. It can be caused by vitamin A deficiency or chronic exposure to arsenic. Hyperkeratosis can also be caused by B-Raf inhibitor drugs such as Vemurafenib and Dabrafenib.It can be treated with urea-containing creams, which dissolve the intercellular matrix of the cells of the stratum corneum, promoting desquamation of scaly skin, eventually resulting in softening of hyperkeratotic areas. Types
Follicular
Follicular hyperkeratosis, also known as keratosis pilaris (KP), is a skin condition characterized by excessive development of keratin in hair follicles, resulting in rough, cone-shaped, elevated papules. The openings are often closed with a white plug of encrusted sebum. When called phrynoderma the condition is associated with nutritional deficiency or malnourishment. This condition has been shown in several small-scale studies to respond well to supplementation with vitamins and fats rich in essential fatty acids. Deficiencies of vitamin E, vitamin A, and B-complex vitamins have been implicated in causing the condition. By other specific site
Plantar hyperkeratosis is hyperkeratosis of the sole of the foot. It is recommended to surgically remove the dead skin, to provide symptomatic relief. Hyperkeratosis of the nipple and areola is an uncommon benign, asymptomatic, acquired condition of unknown pathogenesis.