All articles starting with G
18,970 articles
Grounds of invalidity of treaties
The grounds of invalidity of treaties are the circumstances under the 1969 Vienna Convention, Articles 46 to 53, under which a State's consent to a treaty can be shown invalid.
Groundskeeper Willie
Groundskeeper Willie (William MacDougal) is the Scottish groundskeeper and janitor of Springfield Elementary School in The Simpsons, voiced by Dan Castellaneta since his 1991 debut in "Principal Charming"; the angry-Scotsman accent, IGN ranking, 2014 independence short, and Virdis stereotype study distinguish him.
Groundwater
Groundwater, also called subsurface water or phreatic water, is water held in cracks and spaces of rock and sediment below the Earth's surface, the largest store of liquid freshwater.
Groundwater age dating
Groundwater age dating is the estimation of the time since water recharged an aquifer, inferred from dissolved tracers like CFCs, tritium, and carbon-14 rather than measured directly.
Groundwater discharge
Groundwater discharge is the outflow of water from the saturated zone back to the land surface or to streams, lakes, wetlands, and, in coastal areas, the ocean floor.
Groundwater model
A groundwater model, also known as a groundwater flow model, is a computational method that predicts hydraulic heads, flows, and solute concentrations in aquifers, most often with the USGS MODFLOW code.
Groundwater pollution
Groundwater pollution, also called contaminated groundwater, is the contamination of underground aquifers by pesticides, fertilizers, sewage, and industrial waste, which threatens the drinking water of half the U.S. population.
Groundwater protection
Groundwater protection: preventing aquifer contamination through vulnerability mapping, protection zones, land-use controls, and SDWA, EU, and managed recharge programs worldwide.
Groundwater recharge
Groundwater recharge, also called deep percolation or aquifer recharge, is the downward flow of water from the surface to the water table; managed recharge deliberately adds water to aquifers for storage and recovery.
Groundwood pulping
Groundwood pulping is a mechanical pulping process, developed in 1843 by Friedrich Gottlob Keller, in which logs are pressed against a revolving abrasive grindstone under water, tearing the wood into fibers without chemical cooking.
Groundwork of the Metaphysics of Morals
Groundwork of the Metaphysics of Morals (Grundlegung zur Metaphysik der Sitten), Kant's 1785 ethics treatise published in Riga by Hartknoch, identifies the categorical imperative, grounds morality in autonomy and pure reason, and underlies his later moral works.
Group (mathematics)
In mathematics, a group is a set with a single operation that is associative and has an identity element and inverses, with examples including integers under addition.
Group (military unit)
Group (military unit): a term with several meanings, from brigade-sized US Special Forces groups and battle groups to Army Groups, the largest field formations; distinguishes group from regiment, wing, and squadron usages.
Group (periodic table)
A group of the periodic table is one of the 18 numbered vertical columns of elements, also called families, whose members share the same number of valence electrons.
Group 1 Crew
Group 1 Crew is a Christian hip-hop and dance-pop group formed in 2003 in Orlando, Florida, led by Manwell Reyes with Blanca Callahan and Pablo Villatoro; Fervent Records act that won two Dove Awards.
Group 1001
Group 1001 is an American insurance holding company whose brands include Delaware Life, Gainbridge, Clear Spring, and the RVI Group, with $87.1 billion in assets under management.
Group 11 element
A group 11 element, also called the copper or gold group, is one of four chemical elements: copper, silver, gold, and synthetic roentgenium, with copper, silver, and gold known as the coinage metals.
Group 3 element
Group 3 of the periodic table contains scandium and yttrium, with its lower members disputed: lanthanum and actinium traditionally, or lutetium and lawrencium, and IUPAC found no objective criterion.
Group 47
Group 47, or Gruppe 47, was a loose association of German-language writers who met from 1947 to 1967 to read unpublished work aloud for criticism, becoming the most influential literary institution of postwar West Germany.
Group 5 pulmonary hypertension
Group 5 pulmonary hypertension is the residual classification category for pulmonary hypertension with unclear or multifactorial mechanisms, including sarcoidosis, hematologic disorders, and chronic renal failure.
Group A
Group A: FIA rally classification for modified production cars, homologation basis 5,000 road units; WRC's top category 1987-1996 after Group B's ban, succeeded by World Rally Car rules in 1997; iconic cars include the Lancia Delta Integrale and Subaru Impreza.
Group A streptococcal infection
Group A streptococcal infection: disease caused by Streptococcus pyogenes (group A strep, GAS), from strep throat and impetigo to necrotizing fasciitis, STSS, and rheumatic heart disease; no licensed vaccine, rising US invasive disease since 2014.
Group action
A group action, also called an action of a group, is a way for a group to operate on a set, defined as a homomorphism into its permutations.
Group algebra of a locally compact group
The group algebra of a locally compact group G is the Banach -algebra L¹(G), integrable functions under convolution, the basic object linking Banach algebra theory to harmonic analysis.
Group Areas Act
Group Areas Act (Act 41 of 1950), cornerstone apartheid statute of South Africa, also called GAA; assigned residence and property by race, displaced over 600,000 people including District Six, repealed 1991.
Group B
Group B was the FIA rally regulation category used in the World Rally Championship from 1982 to 1986, known for four-wheel-drive turbocharged cars with over 500 bhp, 200-car homologation, and its ban after the 1986 Toivonen and Portugal fatalities.
Group B streptococcal infection
Group B streptococcal infection, caused by Streptococcus agalactiae (GBS), is invasive disease of newborns, pregnant women, and older or chronically ill adults, prevented in early-onset form by intrapartum antibiotics, with maternal vaccines in development.
Group C nerve fiber
Group C nerve fibers (C fibers, group IV) are unmyelinated, 0.2-1.5 micrometer peripheral axons conducting at 0.5-2 m/s, carrying slow burning pain, temperature, and itch, distinguished from myelinated A fibers.
Group cohesiveness
Group cohesiveness, also called group cohesion or group solidarity, is the unity or solidarity of a group, with task and social dimensions linked to team performance.
Group cohomology
Group cohomology is a branch of homological algebra that assigns abelian groups Hn(G, A) to a group G, measuring how G acts on a module.