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Inversion (music)
Inversion (music): a chord voicing with a non-root bass note (first, second, third inversion; figured bass 6, 6/4; slash chords), also melodic, interval, and contrapuntal inversion; basis of smooth voice leading and cadential 6/4.
Inversion (symmetry)
Inversion is the symmetry operation reflecting every point through a central point, mapping (x, y, z) to (−x, −y, −z); a crystal with it is centrosymmetric, symbol 1̄.
Inversion of control
Inversion of control, also known as the Hollywood Principle, is a software design concept where a framework, rather than the application, controls the timing of calls.
Inversion recovery
Inversion recovery is an MRI pulse sequence in which a 180° pulse inverts magnetization, whose recovery yields T1; choosing the delay nulls a tissue's signal, as in STIR and FLAIR.
Inversion tectonics
Inversion tectonics is the geological process in which a basin formed by extension is later shortened, so its controlling faults reverse movement and the basin fill is uplifted.
Inversion temperature
The inversion temperature of a gas is the temperature at which the Joule–Thomson coefficient changes sign, so expansion below it cools and above it heats the gas, governing liquefaction.
Inversion theorem (probability theory)
An inversion theorem in probability theory recovers a probability distribution, its density, or mass function from a transform, most famously via the Lévy inversion theorem for characteristic functions.
Inversiones Cabildo SpA
Inversiones Cabildo SpA is a Chilean investment holding company in Santiago, the parent vehicle of the Said Group, holding stakes in Parque Arauco, Embotelladora Andina, and Scotiabank.
Invertase
Invertase (β-fructofuranosidase, EC 3.2.1.26, sucrase) hydrolyzes sucrose to glucose and fructose (invert sugar). Historic enzyme used by Michaelis and Menten; commercially from baker's yeast and, since 2024, GM Trichoderma reesei (E 1103, GRN 1173).
Invertebrate
Invertebrate: any animal lacking a backbone, all animals outside subphylum Vertebrata of phylum Chordata. About 90-99% of animal species; insects, molluscs, crustaceans, worms; found in every ecosystem.
Invertebrate nurse cell
Invertebrate nurse cell: germ-line abortive oocyte connected to a growing oocyte by cytoplasmic bridges (ring canals), supplying RNA, proteins, and organelles, as in the Drosophila 16-cell cyst; distinct from Trichinella and thymic nurse cells.
Inverted bow
An inverted bow is a ship bow that slopes backwards above the waterline, with a fine vertical entry and no bulb, best known in Ulstein's X-BOW of 2005.
Inverted duplicated chromosome 15 syndrome
Inverted duplicated chromosome 15 syndrome, also called idic(15) or inv dup(15), is a rare neurogenetic disorder from a maternally derived supernumerary isodicentric chromosome 15 containing the Prader-Willi/Angelman critical region, causing hypotonia, intellectual disability, autism-like behavior, and epilepsy.
Inverted index
An inverted index, also called an inverted file, is a data structure that maps each search term to the documents containing it, central to text search systems.
Inverted Jenny
The Inverted Jenny (Scott C3a) is a 1918 US 24-cent airmail stamp with a blue Curtiss JN-4 biplane printed upside down; one sheet of 100 exists, bought by Robey for $24 in 1918, with position 49 selling for $2,006,000 in 2023.
Inverted junctional epidermolysis bullosa
Inverted junctional epidermolysis bullosa, or JEB inversa, is a rare intermediate form of junctional epidermolysis bullosa in which congenital blistering is confined to intertriginous skin sites.
Inverted nipple
Inverted nipple (retracted nipple): a nipple that turns inward or lies flat against the breast. Congenital in up to 10-20% of females; acquired forms can signal breast cancer and need imaging workup.
Inverted organic solar cell
An inverted organic solar cell reverses the conventional layer order of an organic solar cell, placing the electron-collecting cathode on the substrate for better air stability.
Inverted pendulum
The inverted pendulum, also known as the cart and pole, is a pendulum with its mass above its pivot, making it unstable and a standard benchmark in control theory since 1960.
Inverted perovskite solar cell
An inverted perovskite solar cell is a perovskite photovoltaic device built in the p-i-n layer order, reversing conventional n-i-p stacking, with certified efficiencies exceeding 27%.
Inverted pyramid (journalism)
Inverted pyramid (journalism): news structure with most important facts in a 30-word lead, descending importance below; telegraph-era, AP-standardized, Progressive Era origin, Civil War story a myth; now under digital-era pressure.
Inverted roller coaster
Inverted roller coaster: a steel coaster whose train hangs rigidly beneath the track with dangling legs, pioneered by B&M's Batman: The Ride in 1992; distinct from swinging suspended coasters; examples include Nemesis, Alpengeist, and Banshee.
Inverted roller screw
An inverted roller screw is a planetary roller screw variant in which the nut rotates and the shaft translates, used in compact actuators for aerospace, robotics, and defense.
Inverted spectrum
The inverted spectrum is a philosophy of mind thought experiment in which two people behave alike yet their subjective color experiences differ, first formulated by John Locke.
Inverted sugar syrup
Inverted sugar syrup (invert syrup, invert sugar, CAS 8013-17-0) is a liquid sweetener made by hydrolyzing sucrose into roughly equal glucose and fructose using acid or invertase, used in confectionery, baking, brewing, and bee feed.
Inverted totalitarianism
Inverted totalitarianism is Sheldon Wolin's concept, coined in The Nation in 2003 and developed in Democracy Incorporated (2008), describing corporate dominance over a formally intact democracy, demobilized citizens, and managed elections, inverting classical totalitarianism.
Inverted-F antenna
The inverted-F antenna (IFA) is a compact monopole-type antenna whose shorting pin provides impedance matching; its planar form, the PIFA, is widely used in mobile phones.
Inverter (logic gate)
An inverter, or NOT gate, is the simplest logic gate, with a single input and output that are always opposite: a 0 input gives a 1 output.
Inverter air conditioner
An inverter air conditioner runs its compressor at continuously variable speeds via an inverter, instead of cycling on and off, first launched by Toshiba in 1980.
Inverter model
An inverter model is a mathematical or simulation representation of a power inverter, used in power system engineering, with fidelity levels from switched models, through averaged circuits, to positive-sequence phasor models.