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Apert syndrome
Apert syndrome (acrocephalosyndactyly type I) is an autosomal dominant FGFR2 craniosynostosis disorder with bicoronal suture fusion, midface hypoplasia, and mitten-hand syndactyly, usually de novo with advanced paternal age.
Aperture
In optics, an aperture is a hole, iris, or lens edge that spatially limits light; the aperture stop controls an imaging system's brightness, depth of field, and resolution.
Aperture (song)
Aperture (song): 2026 Harry Styles single, lead and opening track of Kiss All the Time. Disco, Occasionally., written and produced with Kid Harpoon; 5:11 minimal techno-influenced electro-pop that debuted at UK number 1.
Aperture averaging
Aperture averaging is a technique in free-space optical communications in which a large receiver aperture averages out turbulence-induced power fluctuations, reducing scintillation; it was first quantified by D. L. Fried in 1967.
Aperture photometry
Aperture photometry is a standard technique of astronomical photometry that measures brightness by summing light within a circle and subtracting sky background, working best in uncrowded fields.
Aperture stop
An aperture stop is the physical opening in an optical system that limits the cone of light it accepts from an object, controlling image brightness.
Aperture synthesis
Aperture synthesis is an interferometric technique combining signals from widely separated telescopes to achieve the resolution of one aperture as large as the whole array, underlying radio interferometry.
Apertus pretraining corpus
The Apertus pretraining corpus is the openly documented collection of web, code, and mathematics text used to pretrain the Apertus language models, totaling 15 trillion tokens across roughly 1,800 languages and released in September 2025.
Apéry's constant
Apéry's constant, the value of the Riemann zeta function at 3, equals about 1.2020569 and is the sum of the reciprocals of the cubes of the positive integers.
Apethorpe
Apethorpe is a village and civil parish in North Northamptonshire, England, recorded as Patorp in Domesday Book. It is known for Apethorpe Palace (formerly Apethorpe Hall), a Grade I Jacobean country house with thirteen royal visits 1566-1636, and a Roman courtyard villa excavated in 1859.
Apex (2026 film)
Apex (2026) is a Netflix survival thriller directed by Baltasar Kormákur, starring Charlize Theron as a grieving climber hunted by Taron Egerton's killer in the Australian wilderness; released April 24, 2026, 68% on Rotten Tomatoes, 100 million views in under a month.
ApEX (Counter-Strike)
apEX (Dan Madesclaire, born 1993) is a French Counter-Strike in-game leader and entry fragger for Team Vitality; four Major winner (Cluj-Napoca 2015, Paris 2023, Austin and Budapest 2025), 22 Majors played, over 30 S-Tier titles, active until before age 38.
Apex (dinosaur)
Apex is a nearly complete Late Jurassic Stegosaurus skeleton found in 2022 near Dinosaur, Colorado, by Jason Cooper; it sold at Sotheby's in 2024 for a record $44.6 million to Ken Griffin and is on loan to the AMNH.
Apex beat
Apex beat (apical impulse, point of maximal impulse): the palpable left ventricular impulse, normally in the fifth left intercostal space at the midclavicular line; palpable in about 50% of adults and used to assess cardiomegaly and ventricular character.
Apex Legends
Apex Legends is Respawn Entertainment's free-to-play battle royale hero shooter, released February 4, 2019 in the Titanfall universe; 50 million players in 24 days, 20 Hz servers, seasonal live service, Switch delisted August 2026.
Apex predator
Apex predator: top-of-food-web predator with no natural predators as an adult, also called top or alpha predator. Regulates prey and mesopredators, drives trophic cascades; definition varies, humans debated.
APEX trial (NCT01583218)
APEX (NCT01583218) was Portola's phase 3 trial of extended betrixaban versus enoxaparin prophylaxis in 7,513 acutely ill medical patients; cohort 1 missed its primary endpoint, but the FDA approved betrixaban in 2017 while the EMA refused.
Apex.ai
Apex.ai is a German-American automotive software company, founded in 2017 by Jan Becker and Dejan Pangercic, that develops safety-certified middleware for vehicles and mobile machines.
Apexification
Apexification is an endodontic treatment that induces a calcified apical barrier at the open apex of an immature, nonvital permanent tooth, using calcium hydroxide or an MTA plug.
Apfellehrpfad - Percorso informativo su piantagioni di mele
Apfellehrpfad (apple educational trail, percorso informativo su piantagioni di mele): a signposted hiking trail with stations on apple growing, best known in South Tyrol, e.g. Schenna 3.7 km, Tramin 16 stations, Natz-Schabs 7.7-7.9 km.
APG-2449
APG-2449 (CAS 2196186-84-0) is Ascentage Pharma's orally active FAK/ALK/ROS1 triple tyrosine kinase inhibitor, a third-generation ALK TKI with phase 1 ORR 78.6% in TKI-naive ALK+ NSCLC and two China CDE-cleared Phase III studies.
Apgar Patera
Apgar Patera is a 126 km wide patera (volcanic depression) on Venus at 43.10N, 83.80E, named by the IAU in 1991 for Virginia Apgar, the American doctor who created the Apgar newborn score.
Apgar score
Apgar score: rapid 0-10 newborn assessment devised by Virginia Apgar in 1952, scoring color, heart rate, reflexes, tone, and respiration at 1 and 5 minutes; not a predictor of individual outcome or asphyxia diagnosis.
Aphakia
Aphakia is the absence of the crystalline lens in the eye. This condition severely blurs vision and loses accommodation, requiring correction with an IOL or spectacles.
Aphalaridae
Aphalaridae (Löw, 1879) is a family of jumping plant-lice (Psylloidea, Hemiptera), the third largest with about 770 species, including pests such as Gyropsylla spegazziniana and Ctenarytaina eucalypti; its subfamily-level classification remains under revision.
Aphanizomenon
Aphanizomenon is a genus of filamentous, nitrogen-fixing cyanobacteria forming blooms in fresh and brackish waters, producing cyanotoxins and harvested from Upper Klamath Lake, Oregon, as a dietary supplement.
Aphanopus carbo
Aphanopus carbo, the black scabbardfish (peixe-espada-preto), is an elongated bathypelagic cutlassfish (Trichiuridae) of the North Atlantic at 200–2,300 m, basis of the Madeira longline fishery, heavily infected with Anisakis larvae, and nearly indistinguishable externally from A. intermedius.
Aphantasia
Aphantasia is the reduced or absent ability to form voluntary mental imagery, coined in 2015 by Adam Zeman, Michaela Dewar, and Sergio Della Sala; opposite extreme hyperphantasia; prevalence about 3.9%; not a DSM disorder; assessed mainly by VVIQ and binocular rivalry.
Apharan
Apharan is a 2018 Indian Hindi crime thriller web series created by Sidharth Sengupta for ALTBalaji, starring Arunoday Singh as Uttarakhand inspector Rudra Srivastava; 12-episode season 1 premiered 14 December 2018, with season 2, Apharan 2: Sabka Katega, on Voot in March 2022.
Aphasia
Aphasia, also known as dysphasia, is a language disorder caused by damage to the brain's language areas, usually on the left side, most often from stroke.