On rare occasions, anticyclonic tornadoes form in association with the mesoanticyclone of an anticyclonic supercell, in the same manner as the typical cyclonic tornado, or as a companion tornado either as a satellite tornado or associated with anticyclonic eddies within a supercell. Sound and seismology
Tornadoes emit widely on the acoustics spectrum and the sounds are caused by multiple mechanisms. Various sounds of tornadoes have been reported, mostly related to familiar sounds for the witness and generally some variation of a whooshing roar. Popularly reported sounds include a freight train, rushing rapids or waterfall, a nearby jet engine, or combinations of these. Many tornadoes are not audible from much distance; the nature of and the propagation distance of the audible sound depends on atmospheric conditions and topography.The winds of the tornado vortex and of constituent turbulent eddies, as well as airflow interaction with the surface and debris, contribute to the sounds. Funnel clouds also produce sounds. Funnel clouds and small tornadoes are reported as whistling, whining, humming, or the buzzing of innumerable bees or electricity, or more or less harmonic, whereas many tornadoes are reported as a continuous, deep rumbling, or an irregular sound of "noise".Since many tornadoes are audible only when very near, sound is not to be thought of as a reliable warning signal for a tornado.
History
Fludrocortisone was described in the literature in 1953 and was introduced for medical use (as the acetate ester) in 1954. It was the first synthetic corticosteroid to be marketed, and followed the introduction of cortisone in 1948 and hydrocortisone (cortisol) in 1951. Fludrocortisone was also the first fluorine-containing pharmaceutical drug to be marketed. Society and culture
Generic name
Fludrocortisone is the generic name of fludrocortisone and its INN, USAN, BAN, DCF, and DCIT, whereas fludrocortisone acetate is the generic name of fludrocortisone acetate and its USP, BANM and JAN. Brand names
Fludrocortisone is marketed mainly under the brand names Astonin and Astonin-H, whereas the more widely used fludrocortisone acetate is sold mainly as Florinef, but also under several other brand names including Cortineff, Florinefe, and Fludrocortison. Availability
Fludrocortisone is marketed in Austria, Croatia, Denmark, Germany, Luxembourg, Romania, and Spain, whereas fludrocortisone acetate is more widely available throughout the world and is marketed in the United States, Canada, the United Kingdom, various other European countries, Australia, Japan, China, Brazil, and many other countries. References
External links
"Fludrocortisone". Drug Information Portal. U.S. National Library of Medicine.