All articles starting with R

Radical polymerization

Radical polymerization, also known as free radical addition polymerization, is a chain polymerization in which radicals carry chain growth, dominating industrial production of vinyl polymers like polystyrene.

Radical prostatectomy

Radical prostatectomy, also called open radical prostatectomy, is an operation that removes the prostate gland and seminal vesicles to cure prostate cancer confined to the gland, now mostly robot-assisted.

Radical Reformation

The Radical Reformation was the sixteenth-century Protestant current that refused state-backed reform and built voluntary congregations outside the state-church system, its largest branch the Anabaptists, who began rebaptizing adults in Zurich in 1525.

Radical relay C–H functionalization

Radical relay C–H functionalization is a synthetic chemistry strategy in which hydrogen-atom transfer generates a diffusible carbon radical that a second reagent or catalyst functionalizes.

Radical Republicans

Radical Republicans: faction of the 1850s–1877 Republican Party led by Thaddeus Stevens and Charles Sumner, demanding abolition, Black civil rights, and harsh Reconstruction terms for the former Confederacy.

Radical resection

Radical resection is the en bloc surgical removal of a malignant tumor with a margin of healthy tissue and often regional lymph nodes, aiming to leave no cancer cells behind.

Radical retropubic prostatectomy

Radical retropubic prostatectomy: open removal of the prostate, seminal vesicles, and surrounding tissue through a lower abdominal incision; refined by Walsh's 1982 nerve-sparing anatomic technique, now compared with robotic surgery.

Radical right (United States)

The radical right in the United States, also called the populist radical right or far right, combines nativism, authoritarianism, and populism; its lineage runs from paleoconservatism and Buchanan's 1992 America First campaign to Trumpism and transnational networks like CPAC.

Oct 20, 2026

Radical SAM

Radical SAM enzymes, also called radical S-adenosylmethionine enzymes, form the largest enzyme superfamily (over 700,000 sequences). They use a [4Fe-4S] cluster to cleave SAM, generating the 5'-deoxyadenosyl radical via an organometallic Fe-C intermediate for diverse radical reactions.

Radical Smiles rearrangement

The radical Smiles rearrangement is a variant of the Smiles rearrangement in which a free radical triggers migration of an aryl group from sulfur to carbon.

Radical Society

Radical Society: A Review of Culture and Politics was an American quarterly left-wing magazine of politics and culture. It continued Socialist Review and ceased publication after its winter 2006 issue.

Radical substitution

Radical substitution is an organic reaction in which a radical chain mechanism replaces an atom or group in a molecule, best known in the halogenation of alkanes.

Radical trachelectomy

Radical trachelectomy is a fertility-sparing operation for early-stage cervical cancer that removes the cervix, upper vagina, and parametria while preserving the uterus for future pregnancy.

Radical translocation

Radical translocation is an organic chemistry process where a carbon-centered radical relocates within a molecule via intramolecular hydrogen atom transfer, enabling functionalization of remote, inert C–H bonds.

Radical Ventures

Radical Ventures is a Toronto venture capital firm founded in 2017 by Jordan Jacobs and Tomi Poutanen that invests in artificial intelligence companies from incubation through pre-IPO, including Cohere and Waabi.

Radical-nucleophilic aromatic substitution

Radical-nucleophilic aromatic substitution, abbreviated SRN1 and known as the Bunnett reaction, is a radical chain mechanism, proposed by Bunnett in 1970, that replaces halides on unactivated aryl halides through electron transfer.

Radical-polar crossover

Radical-polar crossover is a strategy in organic synthesis in which a radical intermediate undergoes single-electron transfer to an ionic intermediate, combining radical and polar reactivity; the concept dates to 1993.

Radicalization

Radicalization: the phased process of adopting radical beliefs that accept or justify violence for political or ideological goals; fewer than 1% of radicalized individuals commit violent acts; studied at micro, meso, and macro levels.

Oct 21, 2026

Radicular cyst

Radicular cyst (periapical, apical cyst): inflammatory odontogenic cyst on a non-vital tooth, arising from periapical granuloma via epithelial rests of Malassez; diagnosed by histopathology, treated by enucleation or marsupialization.

Radiculopathy

Radiculopathy, also called radiculitis or nerve root disorder, is pain, numbness, tingling, and weakness from a compressed spinal nerve root; types are cervical, thoracic, and lumbar, most often caused by disc herniation.

Oct 10, 2026

Radii Gurzhi

Radii Mykolayovych Gurzhi (1930–2011) was a Soviet and Ukrainian theoretical physicist at Kharkiv whose 1963 prediction of the Gurzhi effect, where a clean conductor conducts better as it warms, founded electron hydrodynamics.

Oct 21, 2026

Radik Isayev

Radik Isayev (Radik İsayev, born 1989, Ukhul, Dagestan) is an Azerbaijani taekwondo fighter, Rio 2016 Olympic +80 kg champion, 2015 world champion, and European champion in 2014 and 2018.

Radio

Radio is a technology for sending information over distance using electromagnetic waves, through a transmitter that modulates a carrier wave and a receiver that recovers it.

Radio (2003 film)

Radio is a 2003 American sports drama directed by Michael Tollin, starring Cuba Gooding Jr. as Radio Kennedy and Ed Harris as the coach who befriends him.

Radio Act of 1912

The Radio Act of 1912 is the first general United States federal law on radio, requiring licenses for stations and operators, passed after the Titanic disaster.

Radio and television channels of Dubai

Radio and television channels of Dubai: state broadcaster Dubai Media Incorporated (Dubai TV, Sama Dubai, Dubai One, Dubai Sports, Dubai Radio 93.0, Noor Dubai 93.9) and commercial networks such as Arabian Radio Network's Dubai Eye 103.8, tracing broadcasting from 1958 to the Dubai+ streaming platform.