All articles starting with E
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Exchange transfusion
Exchange transfusion is a procedure in which a patient's blood is gradually withdrawn and replaced with donor blood, used for severe neonatal jaundice and sickle cell disease.
Exchange Transfusion, Whole Blood
Exchange transfusion, whole blood: replacing a patient's blood aliquot by aliquot with donor whole blood or reconstituted red cells plus plasma. Used for neonatal hyperbilirubinemia, hemolytic disease, and sickle cell disease; double-volume exchange is 160 mL/kg.
Exchange value
Exchange value is the proportion in which one commodity exchanges for others, distinct from use value and price, anchoring classical economics from Smith and Ricardo to Marx.
Exchange-only silicon triple-dot qubit
The exchange-only silicon triple-dot qubit is a spin qubit encoding one qubit in three electron spins on silicon quantum dots, controlled entirely by exchange interaction.
Exchange-rate regime
An exchange-rate regime is how a country manages its currency's value against others, from hard pegs to free floats; the IMF classifies members' actual arrangements into 10 categories.
Exchange-traded fund
An exchange-traded fund (ETF) is an investment fund whose shares trade on a stock exchange throughout the day, combining features of mutual funds and closed-end funds.
Exchangeability
Exchangeability, known in older literature as equivalence, permutability, or symmetry, is a symmetry property of a probability distribution, introduced by Bruno de Finetti and central to Bayesian statistics.
Exchangeable random variables
Exchangeable random variables are a collection whose joint probability distribution is unchanged when their labels are permuted, introduced by Bruno de Finetti and weaker than independence.
Excimer lamp
An excimer lamp is a mercury-free ultraviolet light source emitting a single narrow band from short-lived excited dimers, typically in a dielectric barrier discharge, used for disinfection, water treatment, and coating matting.
Excimer laser
An excimer laser is a pulsed gas laser that emits ultraviolet light from transient noble-gas halide molecules, chiefly used in chipmaking lithography and LASIK eye surgery.
Excinuclease Cho, C-terminal domain
Excinuclease Cho, C-terminal domain: the C-terminal region of Cho (UvrC homolog, gene ydjQ), a bacterial NER endonuclease making only 3′ incisions 4 nt beyond UvrC's site; in Mycobacterium it carries an epsilon 3′ exonuclease-like domain.
Excipient
Excipient: inactive ingredient added to drug products alongside the active pharmaceutical ingredient; from Latin excipere; aids manufacture, stability, bioavailability; 80-90% of product; regulated via FDA IID and EMA guidelines.
Exciplex
An exciplex is an electronically excited complex of two different molecules, non-bonding in the ground state; it falls apart when the excitation is lost, and partners of the same structure form an excimer.
Exciplex emission in organic light-emitting diodes
Exciplex emission in organic light-emitting diodes is light from an excited donor-acceptor complex at interfaces between hole- and electron-transporting materials, exploited since about 2012 as emitter and host.
Excise
An excise, or excise tax, is a selective tax on specified goods such as alcohol, tobacco, and fuel, collected once from a registered operator rather than at every sale.
Excision (film)
Excision is a 2012 American body-horror film, Richard Bates Jr.'s feature debut expanded from his 2008 short, starring AnnaLynne McCord as Pauline, a teen obsessed with surgery, with Traci Lords and Ariel Winter; released by Anchor Bay.
Excision B2B Space Laces (music)
Excision B2B Space Laces is the billed back-to-back dubstep pairing of producers Excision (Jeff Abel) and Space Laces (Ian Slider), whose joint releases span 2013 to 2018 and who headline Lost Lands 2026.
Excision Repair
Excision repair: DNA repair mechanisms (base-excision, nucleotide-excision, mismatch repair) that cut damaged DNA from one strand and resynthesize it using the complementary strand as template.
Excisum
Excisum, ancient Gallo-Roman road station and secondary agglomeration at Eysses near Villeneuve-sur-Lot, Lot-et-Garonne, France; on the Tabula Peutingeriana and Antonine Itinerary between Agen and Périgueux, with forum, basilica, curia, and temple.
Excitability (chemistry)
Excitability in chemistry is the property of a chemical system that rests in a stable steady state but fires a large excitation event when perturbed above a critical threshold.
Excitable Boy
Excitable Boy is Warren Zevon's third album, released January 1978 on Asylum, produced by Jackson Browne and Waddy Wachtel; his breakthrough, containing the #21 hit Werewolves of London and peaking at #8 on the Billboard 200.
Excitation spectroscopy
Excitation spectroscopy is a fluorescence-detected form of absorption spectroscopy that scans the excitation wavelength while recording emission at a fixed wavelength, used on molecules, phosphors, and quantum dots.
Excitation trajectory optimization
Excitation trajectory optimization is the design of a robot's reference motion, often a finite Fourier series, chosen to make estimating dynamic parameters like link masses and friction coefficients as accurate as possible.
Excitation transfer
Excitation transfer is a collision process in which an excited atom or molecule passes its excitation energy to a partner, distinct from the collisionless optical mechanism resonance energy transfer.
Excitation–emission matrix fluorescence spectroscopy
Excitation–emission matrix fluorescence spectroscopy, or fluorescence EEM, measures fluorescence intensity over excitation and emission wavelengths to produce 3D molecular fingerprints, routine in water quality analysis of dissolved organic matter.
Excitatory amino acid transporter 2
EAAT2 (SLC1A2, GLT-1) is the main astrocytic glutamate transporter of the brain, clearing over 90% of extracellular glutamate; its loss is linked to ALS, Alzheimer's, epilepsy, and excitotoxicity.
Excitatory postsynaptic potential
Excitatory postsynaptic potential (EPSP), a depolarizing postsynaptic potential that increases action potential likelihood; distinguished from IPSP by a reversal potential above spike threshold; mediated by glutamate receptors such as AMPA.
Excitebike (エキサイトバイク)
Excitebike (エキサイトバイク) is Nintendo's 1984 Famicom side-scrolling motocross racer, an NES launch title with turbo-overheat mechanics, five tracks, and an early console track editor; later versions include Vs. Excitebike and Excitebike 64.
Excited delirium
Excited delirium (ExD/ExDS) is a disputed agitation syndrome coined in 1980s Miami by Wetli and Fishbain, long used to explain restraint deaths; unrecognized in DSM-5/ICD and abandoned by major medical bodies since 2023.
Excited state
An excited state is a quantum state of an atom or molecule with energy higher than the ground state, reached by absorbing a discrete amount of energy.