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convulsion

(Encyclopedia)convulsion, sudden, violent, involuntary contraction of the muscles of the body, often accompanied by loss of consciousness. It is not known what causes the abnormal impulses from the brain that resul...

desert

(Encyclopedia)desert, arid region, usually partly covered by sand, having scanty vegetation or sometimes almost none, and capable of supporting only a limited and specially adapted animal population. The so-called ...

stem cells

(Encyclopedia)stem cells, unspecialized human or animal cells that can produce mature specialized body cells and at the same time replicate themselves. Embryonic stem cells are derived from a blastocyst (the blastu...

body temperature

(Encyclopedia)body temperature, internal temperature of a living organism. Mammals and birds are termed warm-blooded, or homeothermic, i.e., they are able to maintain a relatively constant inner body temperature, w...

napalm

(Encyclopedia)napalm nāˈpäm [key], incendiary material developed during World War II by Harvard scientists cooperating with the U.S. army and used in bombs and flame throwers. Napalm is based on a mixture of gas...

cofferdam

(Encyclopedia)cofferdam, temporary barrier for excluding water from an area that is normally submerged. Made commonly of wood, steel, or concrete sheet piling (see pile), cofferdams are used in constructing the fou...

Otto, Frei Paul

(Encyclopedia)Otto, Frei Paul ôˈtō [key], 1925–2015, German architect. Most notable for his tensile and pneumatic structures, Otto was among the first major architects to experiment with lightweight design. H...

Medusa, in Greek mythology

(Encyclopedia)Medusa mədo͞oˈsə [key], in Greek mythology, most famous of the three monstrous Gorgon sisters. She was once a beautiful woman, but she offended Athena, who changed her hair into snakes and made he...

Schleicher, Kurt von

(Encyclopedia)Schleicher, Kurt von, 1882–1934, German general. A leading Reichswehr (army) figure after World War I, Schleicher wielded great power in the years before Adolf Hitler came to power (1933). He was wa...

Cohnheim, Julius

(Encyclopedia)Cohnheim, Julius yo͞oˈlyo͝os kōnˈhīm [key], 1839–84, German experimental histologist and pathologist. In a relatively brief life Cohnheim made a series of remarkable contributions to the rapid...