All articles starting with H
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Halo: First Strike
Halo: First Strike is Eric Nylund's 2003 Halo novel, third of the Original Series, bridging Halo: Combat Evolved and Halo 2 as Master Chief, Cortana, and Johnson return to Earth.
Halo: Reach
Halo: Reach is Bungie's 2010 Xbox 360 first-person shooter, a prequel to Halo: Combat Evolved about Noble Team's fall on planet Reach. Known for armor abilities, loadouts, the DMR, expanded Firefight and Forge, and a 91 Metacritic score.
Halo: The Fall of Reach
Halo: The Fall of Reach, Eric Nylund's 2001 Del Rey novel, is the first Halo book and prequel to Combat Evolved, covering John-117's SPARTAN-II origins, the fall of Reach, its comic, animated, and audio drama adaptations, and canon conflicts with Halo: Reach.
Halo: The Flood
Halo: The Flood (2003) by William C. Dietz is the official novelization of Halo: Combat Evolved and the only direct game novelization among around forty Halo novels, adding Covenant and UNSC subplots; reissued by Tor and Gallery Books.
Halo: The Master Chief Collection
Halo: The Master Chief Collection (MCC) is 343 Industries' compilation of the mainline Halo games, launched on Xbox One November 11, 2014 with four games, later expanded to six including Halo: Reach, released on PC in 2019-2020, and known for its broken 2014 matchmaking launch and long recovery.
Haloalkaliphilic archaea
Haloalkaliphilic archaea are microorganisms that require both high salt, at least 0.5 mol/L, and alkaline pH around 9, living in soda lakes such as Lake Natron.
Haloalkane
A haloalkane, also called an alkyl halide or halogenoalkane, is an organic compound in which one or more hydrogens of an alkane are replaced by halogens.
Haloalkane Dehalogenase Enzyme
Haloalkane dehalogenases (HLDs, EC 3.8.1.5), also called DhlA, DhaA, LinB family enzymes, are α/β-hydrolase microbial enzymes that hydrolyze carbon-halogen bonds via an aspartate nucleophile, used in bioremediation, biocatalysis, biosensing, and HaloTag protein labeling.
Haloanilines
Haloanilines are anilines with halogen atoms such as fluorine, chlorine, bromine, or iodine on the ring, used as pharmaceutical and agrochemical intermediates and found as disinfection byproducts in drinking water.
Halobacteriaceae
Halobacteriaceae is a family of halophilic archaea found in salt lakes and brines. Established by N. E. Gibbons in 1974, it was historically the single family containing all archaeal halophiles.
Halobacteriales
Halobacteriales (Grant and Larsen 1989) is an order of extremely halophilic, chemoorganotrophic archaea in the class Halobacteria, type genus Halobacterium; synonyms Haloferacales and Natrialbales, divided by genome analysis into families such as Halobacteriaceae, Haloarculaceae, and Halococcaceae.
Halobacterium
Halobacterium: genus of extremely halophilic archaea (euryarchaeotes), type species H. salinarum, formerly H. halobium; source of bacteriorhodopsin, halorhodopsin, and sensory rhodopsins; type genus of class Halobacteria.
Halobacterium salinarum
Halobacterium salinarum, formerly H. halobium and H. cutirubrum, is an extremely halophilic archaeon from salted fish and salterns, model organism for bacteriorhodopsin, halorhodopsin, and sensory rhodopsins, with the first sequenced haloarchaeal genome (NRC-1).
Halobetasol propionate
Halobetasol propionate: ultra-high potency (class I) synthetic topical corticosteroid (Ultravate, Bryhali, Lexette, Duobrii combination) for plaque psoriasis; 0.05% and 0.01% formulations, two-week to eight-week use limits, 50 g/week cap.
Halobia
Halobia (Bronn, 1830) is a thin-shelled, flat Triassic bivalve genus, cousin of Daonella, used worldwide for Upper Triassic biostratigraphy; not the bacterium Nesterenkonia halobia.
Halocarpus
Halocarpus (monoao, pink pine, bog pine) is a genus of three New Zealand endemic podocarps segregated from Dacrydium by Quinn in 1982, in the Prumnopityoid clade, with inverted epimatium-enclosed seeds and aril-like collars.
Halocline
A halocline is a layer of water where salinity changes rapidly with depth, separating fresher surface water from saltier water below and limiting vertical mixing.
Halodhiya Choraye Baodhan Khai
Halodhiya Choraye Baodhan Khai (English title: The Catastrophe) is a 1987 Assamese social film directed by Jahnu Barua, based on Homen Borgohain's novel of the same name.
Halofantrine
Halofantrine (Halfan, WR171669), a 9-phenanthrenemethanol antimalarial developed by WRAIR and FDA-approved in 1992, treats chloroquine-resistant falciparum and vivax malaria but is now little used because of QT prolongation and fatal cardiotoxicity.
Haloferacales
Haloferacales (Gupta et al. 2015) is an order of extremely halophilic archaea in the class Halobacteria, containing the families Haloferacaceae and Halorubraceae; since 2023 it is merged into Halobacteriales and treated as a synonym.
Haloferax
Haloferax: genus of extremely halophilic archaea in family Haloferacaceae, type species H. volcanii from the Dead Sea; model haloarchaeal genus producing bacterioruberin carotenoids and used in bioremediation and biotechnology.
Haloferax volcanii
Haloferax volcanii, formerly Halobacterium volcanii, is a Dead Sea halophilic archaeon and leading archaeal model organism, with a 2.848 Mb genome plus mini-chromosomes, polyploidy, facile genetics, and biotechnological enzymes.
Haloform reaction
The haloform reaction, also called the Lieben haloform reaction, treats methyl ketones with halogen and base to give carboxylates and haloforms such as iodoform and chloroform.
Halogen
The halogens, also called Group 17 elements, are the five highly reactive nonmetals fluorine, chlorine, bromine, iodine, and astatine, named in 1842 from Greek for salt-producing because they form salts with metals.
Halogen bond
A halogen bond is a directional, noncovalent attraction in which a covalently bound halogen atom acts as a Lewis acid toward an electron-donor site, formally defined by IUPAC in 2013.
Halogen bonding catalysis
Halogen bonding catalysis is a branch of organocatalysis in which a catalyst activates a substrate through a halogen bond, a noncovalent interaction involving an electrophilic halogen atom.
Halogen lamp
A halogen lamp, also called a tungsten-halogen bulb, is an incandescent lamp whose halogen cycle keeps the bulb wall clean and lets the filament run hotter than in ordinary bulbs.
Halogenation
Halogenation is a chemical reaction that introduces one or more halogen atoms (fluorine, chlorine, bromine, or iodine) into an organic molecule by substitution or addition.
Halomethane
A halomethane is a methane derivative in which one or more hydrogen atoms are replaced by fluorine, chlorine, bromine, or iodine, including chloroform and CFCs.
Halomonas
Halomonas is a genus of salt-tolerant, Gram-negative bacteria established in 1980, with about 68 species that grow in high-salt conditions and serve in industrial biotechnology.