Sporadic group - Wikipedia, the free encyclopedia In the mathematical field of group theory, a sporadic group is one of the 26 exceptional groups in the classification of finite simple groups. A simple group is a group G that ...
Permafrost - Wikipedia, the free encyclopedia In geology, permafrost or cryotic soil is soil at or below the freezing point of water 0 °C (32 °F) for two or more years. Most permafrost is located in high latitudes (i.e ...
Aniridia - Wikipedia, the free encyclopedia Aniridia is the absence of the iris. Aniridia usually involves both eyes. It can be congenital or caused by a penetrant injury. Isolated aniridia is a congenital disorder which ...
Ionosphere - Wikipedia, the free encyclopedia The ionosphere ( / aɪ ˈ ɒ n ə s f ɪ ər /) is a part of the upper atmosphere, from about 85 km to 600 km altitude, comprising portions of the mesosphere, thermosphere and ...
Fatal familial insomnia - Wikipedia, the free encyclopedia Fatal familial insomnia (FFI) is a very rare autosomal dominant inherited prion disease of the brain. It is almost always caused by a mutation to the protein PrP C, but can ...