All articles starting with P
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Proto-language
A proto-language is an unattested common ancestor of a language family, such as Proto-Indo-European, reconstructed from daughter languages chiefly by the comparative method, with typological and computational phylogenetic approaches as alternatives.
Proto-Niger–Congo language
Proto-Niger-Congo is the hypothetical, unattested ancestor of the roughly 1,500 Niger-Congo languages of Africa. No full reconstruction exists; partial reconstructions cover numerals, noun classes, and verb extensions, with Atlantic-Congo as the contested family's best-established core.
Proto-oncogene tyrosine-protein kinase Src
Proto-oncogene tyrosine-protein kinase Src (c-Src, SRC gene, UniProt P12931): human non-receptor tyrosine kinase, 536 amino acids, regulated by Csk phosphorylation of Tyr530; counterpart of RSV v-Src, first proto-oncogene, targeted by dasatinib.
Proto-Oncogenes
Proto-oncogenes (c-onc genes) are normal cellular genes regulating cell growth and division that become cancer-driving oncogenes through mutation, amplification, or chromosomal rearrangement; discovered via retroviruses by Bishop and Varmus, 1989 Nobel Prize.
Proto-punk
Proto-punk is a retrospective label for rock styles from the 1960s and early 1970s. It covers raw, stripped-down music from Detroit and New York, like the MC5.
Proto-Renaissance
The Proto-Renaissance, roughly 1200 to 1400, was the transitional phase of Italian art moving from flat Italo-Byzantine style toward naturalism, led by Giotto and Cimabue.
Proto-Semitic language
Proto-Semitic is the unattested reconstructed ancestor of the Semitic branch of Afroasiatic (Arabic, Hebrew, Akkadian, Amharic), reconstructed by the comparative method with VSO order, triptotic case, and an Early Bronze Age Near Eastern origin.
Proto-Sinaitic script
Proto-Sinaitic script, the earliest known consonantal alphabet (abjad), was created around 1900-1700 BC by Semitic workers at Egypt's Serabit el-Khadim turquoise mines by adapting Egyptian hieroglyphs acrophonically; ancestor of Phoenician, Hebrew, Greek, and Latin alphabets.
Proto-Turkic language
Proto-Turkic is the unattested, reconstructed ancestor of the Turkic languages, dated about 2,000-2,500 years BP, splitting first into Oghur (Chuvash) and Common Turkic; its Altaic affiliation and homeland remain disputed.
Proto-Uralic language
Proto-Uralic is the unattested reconstructed ancestor of the Uralic languages (Finnish, Hungarian, Samoyedic). Reconstructed via the comparative method; homeland debated, recently placed east of the Urals; spread tied to the 4.2 ka climate event and Seima-Turbino network.
Proto-writing
Proto-writing: graphic or object-based notation (clay tokens, proto-cuneiform, proto-Elamite, khipus) that records quantities and entities without transcribing a spoken language, the precursor category to true writing.
Protobothrops
Protobothrops is a monophyletic genus of about 14 Asian lance-headed pit viper species, split from Trimeresurus, originating in southwestern China, medically important for hemorrhagic habu venoms.
Protobranchia
Protobranchia (Pelseneer, 1889) is the basal bivalve mollusk subclass, sister to Autobranchia, with over 600 species of small Cambrian-origin deposit feeders, taxodont teeth, pericalymma larvae, and orders Nuculida, Nuculanida, Solemyida.
Protocardia
Protocardia is an extinct genus of cockle-like marine bivalves, abundant in Jurassic and Cretaceous rocks worldwide and recognized by radial ribs on the posterior shell slope.
Protocatechuic acid
Protocatechuic acid, abbreviated PCA, is 3,4-dihydroxybenzoic acid, a naturally occurring phenolic acid in olives, chicory, and other plants, and a metabolite of anthocyanins in humans.
Protoceratops
Protoceratops, including Protoceratops andrewsi, is a small hornless ceratopsian dinosaur from the Late Cretaceous Gobi Desert, discovered in the 1920s Central Asiatic Expeditions, known for its display frill, abundant fossils, and the Fighting Dinosaurs specimen with Velociraptor.
Protochlorophyllide reductase
Protochlorophyllide reductase (LPOR/POR, EC 1.3.1.33) is a light-dependent SDR-family photoenzyme that reduces protochlorophyllide to chlorophyllide in chlorophyll biosynthesis; its nitrogenase-like counterpart DPOR works in the dark, and angiosperms lack it.
Protoclone
Protoclone (Protoclone V1) is a full-body humanoid robot prototype by Clone Robotics, using over 1,000 water-driven artificial muscles on a 3D-printed skeleton, shown twitching in a viral 2025 video.
Protocol (diplomacy)
Protocol (diplomacy): a formal international agreement with the same legal force as a treaty, usually less formal in name or supplementary to a parent convention; types include Protocol of Signature, Optional Protocol, and Protocol to Amend, exemplified by the Montreal Protocol.
Protocol (treaty)
A protocol, in international law, is a treaty instrument that supplements, amends, or extends a parent treaty; the name carries no fixed legal weight, as with the 1987 Montreal Protocol.
Protocol Against the Illicit Manufacturing of and Trafficking in Firearms
The Protocol Against the Illicit Manufacturing of and Trafficking in Firearms, known as the Firearms Protocol, is a United Nations treaty in force since 2005.
Protocol analysis
Protocol analysis is a cognitive psychology research method in which participants verbalize their thoughts while performing a task, and the transcripts are coded to infer mental processes.
Protocol Buffers
Protocol Buffers, also known as Protobuf, is a language-neutral, schema-driven binary serialization system developed at Google and released in 2008, and it defines the message format used by gRPC.
Protocol data unit
A protocol data unit (PDU) is the unit of data exchanged between peer protocol entities in one layer of a network stack, with layer-specific names like segment, datagram, and frame.
Protocol of 2005 to the Convention for the Suppression of Unlawful Acts Against the Safety of Maritime Navigation
The Protocol of 2005 to the Convention for the Suppression of Unlawful Acts Against the Safety of Maritime Navigation is a multilateral treaty adopted in London in 2005.
Protocol on Blinding Laser Weapons
Protocol on Blinding Laser Weapons (Protocol IV to the 1980 CCW), adopted Vienna 13 October 1995, bans using and transferring lasers designed to cause permanent blindness; entered into force 30 July 1998, first weapon banned before battlefield use since 1868.
Protocol on Environmental Protection to the Antarctic Treaty
The Protocol on Environmental Protection to the Antarctic Treaty, known as the Madrid Protocol, is a 1991 treaty designating Antarctica a natural reserve and banning mining.
Protocol on Incendiary Weapons
Protocol III to the 1980 CCW, the Protocol on Incendiary Weapons, restricts napalm-type weapons: it bans attacks on civilians in all circumstances, bars air-delivered incendiaries in concentrations of civilians, and is criticized for excluding white phosphorus.
Protocol stack
A protocol stack, also called a network protocol stack, is a layered set of communication protocols in which each layer provides services to the layer above it, as in TCP/IP.
Protocol-Independent Multicast
Protocol-Independent Multicast (PIM) is a family of IP multicast routing protocols that builds multicast trees using unicast routing information without depending on any specific unicast routing protocol.