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toxin

(Encyclopedia)toxin, poison produced by living organisms. Toxins are classified as either exotoxins or endotoxins. Exotoxins are a diverse group of soluble proteins released into the surrounding tissue by living ba...

Rulers of the Roman Empire (table)

(Encyclopedia)Rulers of the Roman Empire(including dates of reign) Emperors in the East(until the fall of Rome; see table entitled Rulers of the Byzantine Empireat Byzantine Empire for later emperors) Empero...

sandstone

(Encyclopedia)sandstone, sedimentary rock formed by the cementing together of grains of sand. The usual cementing material in sandstone is calcium carbonate, iron oxides, or silica, and the hardness of sandstone va...

smut

(Encyclopedia)smut, name for an order of parasitic fungi (Ustilaginales) and the various diseases of plants caused by them. Smuts produce sootlike masses of spores on the host. The spore masses may break up into a ...

permafrost

(Encyclopedia)permafrost, permanently frozen soil, subsoil, or other deposit, characteristic of arctic and some subarctic regions; similar conditions are also found at very high altitudes in mountain ranges. In 196...

fracture

(Encyclopedia)fracture, breaking of a bone. A simple fracture is one in which there is no contact of the broken bone with the outer air, i.e., the overlying tissues are intact. In a comminuted fracture the bone is ...

Ramus, Petrus

(Encyclopedia)Ramus, Petrus pyĕr də lä rämāˈ [key], 1515–72, French humanist and philosopher. Attempting to break through Aristotelian and scholastic traditions, Ramus wrote a number of works that became in...

masque

(Encyclopedia)masque, courtly form of dramatic spectacle, popular in England in the first half of the 17th cent. The masque developed from the early 16th-century disguising, or mummery, in which disguised guests be...

cotton gin

(Encyclopedia)cotton gin, machine for separating cotton fibers from the seeds. The charkha, used in India from antiquity, consists of two revolving wooden rollers through which the fibers are drawn, leaving the see...

Ghats

(Encyclopedia)Ghats gŏts [key] [Hindi,=steps], two mountain ranges of S India, paralleling the coasts of the Arabian Sea and the Bay of Bengal and forming two sides of the Deccan plateau. Anai Mudi (8,841 ft/2,695...