All articles starting with S
44,216 articles
Spintronic artificial neurons
Spintronic artificial neurons are nanoscale magnetic devices, typically magnetic tunnel junctions, that reproduce the integrating and spiking behavior of biological neurons for low-power neuromorphic computing.
Spintronics
Spintronics, or spin transport electronics, is a branch of electronics that uses electron spin as well as charge, enabling devices like GMR hard disk read heads and MRAM.
Spinulosida
Spinulosida (Perrier, 1884) is an order of sea stars in class Asteroidea, superorder Spinulosacea, now restricted to the family Echinasteridae with genera Echinaster and Henricia, defined by reticulated spiny body plates.
Spinus
Spinus is a genus of finch family birds holding the American siskins and goldfinches plus the Eurasian siskin and Tibetan serin, comprising 20 species, many moved from Carduelis.
Spiny dogfish
Spiny dogfish (Squalus acanthias), also spurdog or piked dogfish: small venom-spined cold-temperate shark with 18–24 month gestation, IUCN Vulnerable; North Pacific form is the separate species S. suckleyi.
Spiny lobster
Spiny lobsters (family Palinuridae, rock lobsters) are clawless decapod crustaceans with spiny bodies and long antennae, a months-long phyllosoma larva, a puerulus postlarva, and major tropical fisheries such as the Caribbean spiny lobster Panulirus argus.
Spion Kop (stadiums)
A Spion Kop, or Kop, is a large single-tier terrace or stand at a sports stadium, named after a hill where British soldiers died in the 1900 Boer War.
Spiperone
Spiperone, also known as spiroperidol, is a butyrophenone dopamine antagonist developed by Janssen Pharmaceuticals as an antipsychotic, and a standard radioligand for labeling dopamine D2 receptors.
Spira Spica
Spira Spica (スピラ・スピカ) is a Japanese pop-rock project from the Kansai region, fronted by vocalist Mikiha and known for the My Dress-Up Darling opening theme Sansan Days.
Spiraea
Spiraea (spirea, bridal-wreaths), a Rosaceae shrub genus published by Linnaeus in 1753, native to the temperate Northern Hemisphere with about 100 accepted species, most diverse in eastern Asia; Japanese spiraea is invasive in the US.
Spiral
A spiral, in mathematics, is a curve whose radius changes as it revolves about a fixed point, winding ever outward or inward; Archimedes studied it about 225 BC.
Spiral (2021 film)
Spiral: From the Book of Saw (2021) is the ninth Saw film, directed by Darren Lynn Bousman from Chris Rock's idea, starring Rock, Samuel L. Jackson, and Max Minghella as police hunt a Jigsaw-style killer targeting corrupt cops; released May 14, 2021, it earned 39% on Rotten Tomatoes.
Spiral (TV series)
Spiral (Engrenages) is a French police and legal drama, Canal+'s first internationally successful crime series, running eight seasons (2005–2020, 86 episodes) about Paris's 2e DPJ unit, with Laure Berthaud, Joséphine Karlsson, and Judge Roban; International Emmy 2015.
Spiral antenna
A spiral antenna is a wideband, frequency-independent antenna with conductive arms wound in a spiral, radiating circularly polarized waves; it is used in direction finding, electronic warfare, and GPS.
Spiral arm
A spiral arm is a region of denser gas, dust, and young stars winding outward from the center of a disk galaxy, giving spiral galaxies their pinwheel appearance.
Spiral bevel gear
A spiral bevel gear is a bevel gear with curved, oblique teeth that transmit power between intersecting shafts, most often at 90 degrees, more smoothly than straight bevel gears.
Spiral Cone-Beam Computed Tomography
Spiral cone-beam computed tomography, also called helical cone-beam CT, unites a cone-shaped x-ray beam with continuous spiral gantry rotation and table movement, first published in 1991.
Spiral CT
Spiral CT, also called helical CT, is a CT mode in which the tube rotates continuously while the table moves, scanning a whole volume in 20 to 60 seconds.
Spiral enteroscopy
Spiral enteroscopy is a device-assisted deep enteroscopy technique in which a rotating spiral-tipped overtube pleats the small intestine over the enteroscope, allowing diagnosis and treatment of small-bowel disease.
Spiral galaxy
A spiral galaxy is a galaxy with a rotating disk of stars, gas, and dust arranged in spiral arms around a central bulge, like the Milky Way.
Spiral ganglion
The spiral ganglion is a group of sensory neurons in the cochlea of the inner ear that relays sound information from hair cells to the brainstem.
Spiral Jetty
Spiral Jetty, Robert Smithson's 1970 counterclockwise basalt earthwork at Rozel Point, Great Salt Lake, Utah; 1,500 ft long, Dia-owned since 1999, National Register 2024.
Spiral learning
Spiral learning is a curriculum-design method in which topics are revisited repeatedly at increasing difficulty, credited to Jerome Bruner's 1960 book The Process of Education.
Spiral model
The spiral model, or Boehm spiral, is a risk-driven software development process model described by Barry Boehm of TRW in 1988, best suited to large, high-risk projects.
Spiral of silence
Spiral of silence: Elisabeth Noelle-Neumann's 1974 public opinion theory; minority holders stay silent fearing isolation, letting perceived majorities dominate discourse and media. Meta-analytic pooled r = .10.
Spiral phase plate
A spiral phase plate is a transparent optical element whose thickness varies with angle, twisting a laser beam into a vortex beam that carries orbital angular momentum.
Spiral search
Spiral search is a blind robotic strategy for peg-in-hole assembly in which a peg winds outward in a spiral, pressing down until it drops into the hole.
Spiral staircase
A spiral staircase is a stair whose wedge-shaped treads wind in a helix around a central column, letting the flight climb in a tight circular footprint; a helical stair winds around a central void instead.
Spiral Tribe
Spiral Tribe (SP23) is a London-formed 1990 nomadic free party sound system collective that staged illegal techno raves, headlined the 1992 Castlemorton festival, faced conspiracy charges, and seeded Europe's teknival movement via its Network 23 label.
Spiral wave
A spiral wave is a self-sustaining rotating excitation pattern in excitable media such as the Belousov–Zhabotinsky reaction and cardiac tissue, where spiral break-up underlies fibrillation.