All articles starting with R
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Radiotrophic fungus
A radiotrophic fungus is a melanized fungus that grows toward, and sometimes grows faster under, ionizing radiation, apparently using melanin; Cladosporium sphaerospermum from Chernobyl is the best-known example.
Radioulnar synostosis-microcephaly-scoliosis syndrome
Radioulnar synostosis-microcephaly-scoliosis syndrome, or Giuffrè–Tsukahara syndrome (OMIM 603438), is an extremely rare genetic disorder combining forearm bone fusion, microcephaly, scoliosis, short stature, and intellectual disability, with about 13 reported cases.
Radish
Radish (Raphanus sativus), also daikon (大根, great root), a cool-season Brassicaceae root vegetable harvested 3-5 weeks after planting; pungency comes from slow growth, and daikon roots reach about 18 inches and 5-6 pounds.
Radisson Blu
Radisson Blu, formerly Radisson SAS, is an upper upscale hotel brand created in 1994, renamed in 2009, and the largest upper upscale hotel brand in Europe.
Radisson Blu Bamako attack
The Radisson Blu Bamako attack: 20 November 2015 jihadist assault on Bamako's Radisson Blu hotel by two al-Mourabitoun gunmen with AK-47s and grenades, killing about 20 and holding 170 hostages before Malian, French, and US forces ended the nine-hour siege.
Radisson Converter Station
Radisson Converter Station is an HVDC converter station in northern Manitoba, owned by Manitoba Hydro near Gillam, which converts AC from Nelson River hydroelectric stations to DC for transmission to Winnipeg.
Radisson Hotels
Radisson Hotels is the central brand of Radisson Hotel Group, a Brussels-based company owned by Jin Jiang International that operates over 1,640 hotels in Europe, Asia-Pacific, and beyond.
Radithor
Radithor was a patent medicine of radium dissolved in distilled water, sold as a cure-all tonic from about 1925 to 1930 by Bailey Radium Laboratories of East Orange, New Jersey.
Raditladi (Mercurian crater)
Raditladi is a 257-km peak-ring impact basin on Mercury near 27°N, 119°E, discovered by MESSENGER's first flyby and named in 2008; about 1.1 Ga old, with graben, smooth plains, and hollows on its peak ring.
Raditude
Raditude is Weezer's seventh studio album, released October-November 2009 on DGC/Geffen/Interscope, named by actor Rainn Wilson, featuring Lil Wayne and Dr. Luke collaborators, and scoring 57 on Metacritic.
Radium
Radium (element 88, Ra) is an intensely radioactive alkaline earth metal discovered by the Curies in 1898 and once used in luminous paint and quack health tonics.
Radium fad
Radium fad: the early 20th-century craze after the Curies' 1898 discovery of radium, when radium was sold in toothpaste, tonics like Radithor, and luminous watch dials, ended by the Radium Girls lawsuits and Eben Byers' 1932 death.
Radium Girls
The Radium Girls, also known as radium dial painters, were young women who painted glowing watch dials with radium paint in the 1910s and 1920s and were fatally poisoned.
Radium jaw
Radium jaw: occupational osteonecrosis of the jaw named by dentist Theodor Blum in 1923-1924 among radium dial painters (the Radium Girls) who ingested radium by lip-pointing brushes; radium deposited in bone like calcium, destroying the jaw.
Radium monofluoride
Radium monofluoride (RaF) is a radioactive diatomic molecule of radium and fluorine, first laser-studied at CERN's ISOLDE facility in 2020 and valued for its sensitivity to physics beyond the Standard Model.
Radium-226
Radium-226 is the longest-lived isotope of radium, with a half-life of 1600 years, once used in luminous watch dials and cancer therapy and still used as a calibration standard.
Radius
A radius is the straight line from the center of a circle to any point on its circumference, equal to half the diameter and denoted r.
RADIUS
RADIUS (Remote Authentication Dial-In User Service) is a client–server protocol carrying authentication, authorization, and accounting data, and the standard for Wi-Fi, DSL, and dial-up access.
Radius (bone)
Radius: the lateral, thumb-side long bone of the forearm, articulating with humerus, ulna, and carpal bones; about 25 cm in adults; enables pronation and supination; distal radius fractures are common.
Radius (film)
Radius (2017) is a Canadian sci-fi thriller by Caroline Labrèche and Steeve Léonard starring Diego Klattenhoff and Charlotte Sullivan: an amnesiac man whose 50-foot death field kills anyone nearby, premiered at Fantasia.
Radius Health
Radius Health, once also operating as Nuvios Inc., was a biopharmaceutical company best known for TYMLOS (abaloparatide), an osteoporosis drug FDA-approved in 2017; it was combined into Paratek Pharmaceuticals in 2026.
Radius of convergence
The radius of convergence, or interval of convergence, of a power series is the number R within which the series converges, equal to the distance to the nearest singularity.
Radius of curvature
The radius of curvature of a curve at a point is the radius of the circle that best approximates the curve there, equal to one over the curvature.
Radius of gyration
The radius of gyration is the distance from an axis at which a body's whole mass, concentrated as a point, would give the same moment of inertia.
Radius of influence
The radius of influence of a pumping well is the maximum distance up to which pumping significantly affects the aquifer, a concept used in wellhead protection and permitting.
Radius of maximum wind
The radius of maximum wind (RMW) is the distance from a tropical cyclone's center to its maximum winds, generally at the inner edge of the eyewall in strong hurricanes.
Radius valley
The radius valley, also known as the radius gap or Fulton gap, is a scarcity of close-in exoplanets between 1.5 and 2.0 Earth radii, first resolved by the California-Kepler Survey in 2017.
Radix
The radix, also called the number base or numeral base, is the count of distinct digits a positional numeral system uses, such as 10 for decimal or 2 for binary.
Radix sort
Radix sort is a non-comparison sorting algorithm that sorts integers or strings one digit at a time with stable passes, achieving linear time when digits are fixed.
Radix Trading
Radix Trading, LLC is a Chicago proprietary trading firm founded in 2012 by Benjamin Blander and Michael Rauchman, developing strategies through machine learning and statistics.