All articles starting with E
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Erdős–Kac theorem
The Erdős–Kac theorem, proved by Paul Erdős and Mark Kac in 1940, states that the number of distinct prime factors of an integer is normally distributed.
Erdős–Ko–Rado theorem
A theorem in extremal set theory stating that an intersecting family of k-element subsets of an n-element set has at most n−1 choose k−1 members, proved in 1938.
Erdős–Rényi model
The Erdős–Rényi model is a random graph model in which each possible edge appears independently with fixed probability, introduced by Paul Erdős and Alfréd Rényi in 1959.
Erdős–Straus conjecture
The Erdős–Straus conjecture is an unsolved problem in number theory, posed by Paul Erdős and Ernst Straus in 1948, stating that 4/n is always a sum of three unit fractions.
Erdős–Szemerédi theorem
A 1983 theorem in additive combinatorics stating that every finite set of integers has a large sum set or product set, of size at least |A|^{1+δ}.
Erdős–Tetali theorem
The Erdős–Tetali theorem is a 1990 result in additive number theory, proved by Paul Erdős and Prasad Tetali, that economical asymptotic bases of order k exist for every fixed k.
Erdős–Turán conjecture on additive bases
The Erdős–Turán conjecture on additive bases, posed by Paul Erdős and Pál Turán in 1941, is an open problem stating that representations cannot be bounded.
Erdosteine
Erdosteine, a thiol-based mucoactive prodrug (N-(carboxymethylthioacetyl)-homocysteine thiolactone) activated to metabolite M1, treats acute and chronic pulmonary disease; RESTORE showed reduced COPD exacerbation rate and duration.
Ère des attentats
Ère des attentats, the 1892–1894 French anarchist campaign of bombings and assassinations, from the princesse de Sagan dynamite attack to President Sadi Carnot's assassination; term coined by historian Jean Maitron.
Erebidae
Erebidae (Leach, 1815), also called erebid moths, is the largest family of Lepidoptera with about 25,000 species in 18 subfamilies, including tiger moths, tussock moths, and underwings, within Noctuoidea.
Erebus (ρεβος)
Erebus (Ἔρεβος, Erebos), Greek primordial god of darkness born of Chaos with Nyx in Hesiod's Theogony; father with Nyx of Aether and Hemera, and also the name of the dark passage between earth and Hades.
Erebus and Terror Gulf
Erebus and Terror Gulf is a gulf of the Weddell Sea at the northern tip of the Antarctic Peninsula, named after Ross's ships HMS Erebus and HMS Terror.
Erebus Fracture Zone
Erebus Fracture Zone, a Southern Ocean seafloor fracture zone in the GEBCO gazetteer, named for HMS Erebus of the Ross Expedition; proposed by Steven C. Cande in 1995, depths 3,400 to 4,000 m.
Erebus Montes
Erebus Montes is a group of mountains in Mars' northern hemisphere near 35.7°N, 185°E, IAU-approved in 1982 from an Antoniadi albedo feature; eroded Noachian-Hesperian highland remnants bearing lobate debris aprons from past glaciation.
Erec
Erec is the hero of Chrétien de Troyes's Old French romance Erec et Enide (ca. 1170), who marries Enide, and the namesake of Hartmann von Aue's German adaptation, Erek.
Erec and Enide
Erec and Enide (Old French Erec et Enide) is a verse Arthurian romance by the twelfth-century French poet Chrétien de Troyes and the first known Arthurian romance.
Erech Sulcus
Erech Sulcus is a 953-km-wide band of bright grooved terrain on Jupiter's moon Ganymede, cutting north-south across Marius Regio and intersecting Sippar Sulcus; IAU-named in 1985 after an Akkadian town built by Marduk.
Erechtheion (ρέχθειον)
Erechtheion (Ερέχθειον), also Erechtheum: Ionic temple on the Athenian Acropolis, built 421–406 BC by Mnesikles for Athena and Poseidon, with the six-Caryatid south porch and north porch over Poseidon's trident marks.
Ereck Flowers
Ereck Flowers Sr., Miami-born NFL offensive lineman, ninth overall 2015 draft pick of the Giants; struggled at tackle, revived his career at guard with Washington and Miami, 105 games, 101 starts, released 2022.
Erectile dysfunction
Erectile dysfunction (ED, impotence): persistent inability to achieve or maintain an erection sufficient for sexual activity. Affects up to 52% of men aged 40–70; vasculogenic in up to 80% of cases; treated first with PDE5 inhibitors (sildenafil, tadalafil).
Erection
Erection (penile erection, tumescence): hardening and enlargement of the penis as blood fills the corpora cavernosa, driven by nitric oxide and nervous-system signals; three types, ED when impaired.
Erection Hardness Score
Erection Hardness Score (EHS, also EHGS): single-item patient-reported 0-4 scale of penile rigidity developed in 1998 for sildenafil trials, validated 2007 by Mulhall et al., used as an adjunct ED outcome measure.
Erection of the Pillar Edicts and monolithic pillars
The erection of the Pillar Edicts and monolithic pillars (स्तंभ लेख) was the program by which Mauryan emperor Ashoka (r. 268–232 BC) raised inscribed sandstone columns across present-day India.
Erector Set
The Erector Set is a metal construction toy patented by A.C. Gilbert in 1913 and sold by his New Haven company, the leading American construction toy of the twentieth century.
Erector spinae muscles
Erector spinae (sacrospinalis): the intermediate layer of deep back muscles, three columns (spinalis, longissimus, iliocostalis) extending the spine from cranium to pelvis; target of the ESP block.
Erector spinae plane block
The erector spinae plane block, or thoracic erector spinae plane block, is a regional anesthesia technique that anesthetizes thoracic spinal nerves for perioperative and chronic pain relief.
Eredivisie
Eredivisie (VriendenLoterij Eredivisie), the Netherlands' top professional football league, founded 1956; 18 clubs, Ajax/PSV/Feyenoord dominate with 33, 23, and 14 titles; known for youth development.
Eredivisie comeback tournament
FOX Sports Eredivisie Comeback, the August 2020 Dutch football comeback tournament of friendlies between Eredivisie and Keuken Kampioen Divisie clubs, played after the Covid-cancelled 2019/20 season, broadcast nearly daily on FOX Sports from 31 July to late August 2020.
EREG
EREG (epiregulin, EPR) is a human chromosome 4q13.3 gene encoding an EGF-family peptide growth factor that binds EGFR and ErbB4 as a low-affinity, long-acting ligand, released by ADAM17, and implicated in inflammation, wound healing, fibrosis, and cancer progression.
Erekle I of Kakheti
Erekle I of Kakheti, in Persian service Nazar Ali Khan, was a Georgian Bagrationi prince who reigned as king of Kartli from 1688 and king of Kakheti from 1703.