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Stiff-person syndrome

Stiff-person syndrome (SPS), also called stiff-man syndrome or stiff person spectrum disorder (SPSD), is a rare autoimmune neurological disorder causing trunk and limb rigidity, stimulus-triggered spasms, and falls, linked to GAD65 antibodies and often misdiagnosed.

Stiffness

Stiffness is the resistance of an object or material to elastic deformation under load: for a material it is an elastic modulus, for a component a spring rate.

Stiffness control

Stiffness control is a robot force-control method, introduced by J. Kenneth Salisbury in 1980, that makes the end effector behave like a programmable, computer-controlled spring.

Stiffness estimation from interaction

Stiffness estimation from interaction is the online identification of the stiffness of an environment, object, or human limb from forces and motions a robot measures in contact.

Stiffness of joint

Joint stiffness (stiff joints) is the sensation of limited or difficult joint motion after inactivity, a major symptom of arthritis. Inflammatory causes produce prolonged morning stiffness over 30-60 minutes; mechanical causes such as osteoarthritis produce brief stiffness under 30 minutes.

Stifone

Stifone: village of about 40 inhabitants in Narni municipality, Umbria, on the Nera river; ancient Roman river port with a shipyard, medieval mills, and Italy's first central-Italian hydroelectric plant (1892, Aldo Netti).

Stiftchenzellen

Stiftchenzellen are sensory epidermal cells of frog tadpoles described by Kölliker in 1885 and identified by electron microscopy by Whitear in 1976; they bear apical microvilli, form synaptic contacts with epidermal nerve fibres, and are proposed chemoreceptors.

Stig Anderson

Stig 'Stikkan' Anderson (1931–1997), Swedish lyricist, publisher, and ABBA's manager; founded Sweden Music and Polar Music, co-wrote 'Waterloo' and other ABBA hits, sold to PolyGram in 1989, and founded the Polar Music Prize.

Stig Claesson

Stig Claesson (1917–1988) was a Swedish physical chemist who led the Institute of Physical Chemistry at Uppsala University and worked on adsorption analysis, colloids, and fast reactions.

Stig Dagerman

Stig Dagerman was a Swedish writer and journalist, a leading figure of the 1940s literary generation. He wrote four novels and over 1,350 daily satirical verses.

Stig of the Dump

Stig of the Dump is a 1963 children's novel by Clive King, in which a boy named Barney befriends a stone-age boy living in a chalk-pit dump.

Stig Rønne

Stig Rønne, full name Hans Stig Trappaud Rønne, was a Danish gymnast who won a gold medal in the team all-around, free system, at the 1920 Antwerp Olympics.

Stigand

Stigand (c. 1000–1072) was an English prelate who served as archbishop of Canterbury from 1052 to 1070, in a tenure never recognized by five successive popes.

Stigler's law of eponymy

Stigler's law of eponymy is the proposition that no scientific discovery is named after its original discoverer, set out by statistician Stephen Stigler in 1980 and credited to Robert Merton.

Stigmaeidae

Stigmaeidae is a family of small predatory mites in the superfamily Raphignathoidea, found worldwide on plants and in soil and feeding mostly on plant-feeding mites.

Stigmasterol

Stigmasterol, also called stigmasterin, is a plant sterol found in soybean oil and vegetable oils, one of the three dominant dietary phytosterols and a starting material for synthesizing progesterone and other steroid drugs.

Stigmata

Stigmata, also called holy stigmata, are bodily marks or pains matching the wounds of the crucified Jesus Christ, reported almost entirely among Catholics since Francis of Assisi in 1224.

Stigmata (film)

Stigmata is a 1999 American supernatural horror film directed by Rupert Wainwright, in which an atheist hairdresser in Pittsburgh develops the wounds of Christ and the Vatican sends a priest to investigate.

Stigmergy

Stigmergy is a mechanism of indirect coordination in which agents communicate by modifying the environment, guiding other agents' later behavior without centralized control; it was coined in 1959 by Pierre-Paul Grassé.

Stihl

Stihl, formally Andreas Stihl AG & Company, is a German family-owned manufacturer of outdoor power equipment, founded in Stuttgart in 1926 and the world's top-selling chainsaw brand since 1971.

Sep 19, 2026

Stihl family

The Stihl family (German: Familie Stihl) is the owner family of STIHL, the Waiblingen-based maker of the world's best-selling chainsaw brand, founded by Andreas Stihl in 1926.

Stijn Claessens

Stijn Claessens is a Dutch financial economist who held senior roles at the World Bank, IMF, and BIS, and is an Executive Fellow at Yale.

Stijn Streuvels

Stijn Streuvels, pseudonym of Frank Lateur (1871–1969), was a Belgian naturalistic novelist of Flemish farming life, whose masterpiece De vlaschaard (1907) is his best-known book.

Stijn Van Nieuwerburgh

Stijn Van Nieuwerburgh is a Belgian-born economist at Columbia Business School known for research on housing collateral, mortgage credit, and remote work's effect on office real estate.

Sep 21, 2026

Stijn Wuyts

Stijn Wuyts is a professor of astrophysics at the University of Bath, holding the Hiroko Sherwin Chair in Extragalactic Astronomy and studying galaxy formation and evolution.

Stikine River

Stikine River (Shtax'héen, "Great River" in Tlingit): a 640 km transboundary river from BC's Spatsizi Plateau to Wrangell, Alaska; fourth-longest in BC, Tahltan territory, with a 300 m deep Grand Canyon, abandoned BC Hydro dam plans, and Red Chris and Galore Creek mines on its Iskut tributary.

STIL

STIL (SCL/TAL1 interrupting locus, SIL) is a human gene at 1p33 encoding a centriole duplication protein, ortholog of SAS-5/ANA-2. Knockout mice lack centrioles and cilia and die midgestation; truncating mutations cause autosomal recessive primary microcephaly MCPH7.