All articles starting with P
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Platonic dialogue
A Platonic dialogue is a philosophical work by Plato written as a conversation among a small number of interlocutors, almost always including Socrates; the form shapes nearly all his writings.
Platonic love
Platonic love: Plato's concept of erôs as desire ascending from a beautiful person toward the Form of Beauty (Symposium, Phaedrus), later renamed Amor Platonicus by Ficino and transformed in modern English into non-sexual affection.
Platonic solid
A Platonic solid, also called a regular solid, is a convex polyhedron with identical regular polygon faces meeting at each vertex; exactly five exist: the tetrahedron, cube, octahedron, dodecahedron, and icosahedron.
Platonism
Platonism: the view that abstract objects (numbers, universals, Forms) exist independently of minds and matter, founded on Plato's theory of Forms and developed through the Academy, Middle Platonism, Neoplatonism, and the Renaissance; contrasted chiefly with nominalism and immanent realism.
Platonov
Platonov (Безотцовщина, Fatherlessness) is Anton Chekhov's long first play, named after its schoolteacher hero Mikhail Platonov; written in his youth, it went unstaged and was first published in 1923.
Platoon
Platoon: a military subdivision of a company or troop, two or more squads or sections, roughly 16-50 soldiers, normally led by a lieutenant with a platoon sergeant; from French peloton.
Platoon (film)
Platoon (1986) is Oliver Stone's Vietnam War film, based on his 1967-68 infantry service, starring Charlie Sheen, Tom Berenger, and Willem Dafoe; it won four Oscars including Best Picture and grossed $137.9 million.
Platoon dispersion model
The platoon dispersion model is a traffic-flow model, formulated by Dennis Robertson in 1969 for TRANSYT, that predicts how vehicle platoons spread between signalized intersections.
Platt Adams
Platt Adams (1885-1961), American track and field athlete of the New York Athletic Club; 1912 Olympic gold in standing high jump (1.63 m) and silver in standing long jump (3.36 m), brother of Ben Adams.
Platt Amendment
Platt Amendment: 1901 US rider to the Army Appropriations Bill, drafted by Elihu Root and named for Senator Orville Platt, defining US-Cuba relations; treaty of May 22, 1903; gave the US intervention rights and the Guantánamo Bay lease; repealed 1934.
Platt scaling
Platt scaling, also known as Platt calibration, is a post-hoc calibration method that fits a sigmoid to a classifier's raw scores, converting them into probabilities; John Platt introduced it for support vector machines.
Platte River
The Platte River, formed by the North and South Platte in Nebraska, is a braided Great Plains river flowing to the Missouri. Known for sandhill crane staging, whooping crane critical habitat, and Colorado-Nebraska water disputes.
Platte River Equity
Platte River Equity is a private equity firm founded in 2006 and based in Denver, Colorado, investing in lower middle market industrial companies across North America.
Plattetombe of Waasmont
Plattetombe of Waasmont (Waasmontse Tom, Tombe Pepin), a huge Gallo-Roman tumulus of the 2nd century AD near Landen, Flemish Brabant, Belgium; over 70 m across, never excavated, protected since 1979.
Platts
Platts, a price reporting agency founded in 1909, is an S&P Global brand publishing over 15,000 daily commodity price assessments, including the Dated Brent oil benchmark.
Platyceras
Platyceras (Conrad 1840) is an extinct caplike platyceratid gastropod, Silurian to Permian (possibly Triassic), abundant in Devonian rocks, famous for attaching over crinoid anal vents in a debated parasitic or commensal association.
Platycercus
Platycercus, the rosellas, is an Australian genus of about six broad-tailed parrots erected by Vigors in 1825, split into subgenera Platycercus and Violania, ranging 25-36 cm.
Platycerium
Platycerium, commonly called staghorn fern or elkhorn fern, is a pantropical genus of about 18 species of epiphytic ferns named for their antler-like fertile fronds.
Platycladus orientalis
Platycladus orientalis (Chinese arborvitae, 侧柏, formerly Thuja orientalis) is the sole species of its genus, a Cupressaceae conifer native from the Russian Far East to east-central China and Korea, with vertical sprays, wingless seeds, and over 40 cultivars.
Platycnemididae
Platycnemididae, the white-legged damselflies or featherlegs, is an Old World family of Zygoptera damselflies with over 400 species, mostly tropical stream dwellers; males of Platycnemis have broadened white tibiae used in courtship.
Platycodon grandiflorus
Platycodon grandiflorus, balloon flower (jiegeng, doraji, kikyo), sole species of its genus in Campanulaceae; East Asian perennial whose saponin-rich root is a traditional cough remedy, vegetable, and pharmacopoeial medicine.
Platyctenida
Platyctenida (Bourne, 1900) is an order of benthic comb jellies in class Tentaculata, phylum Ctenophora, with 49 described species in six families including Benthoplanidae, Coeloplanidae, and Tjalfiellidae; adults live on cnidarians, echinoderms, sponges, or algae.
Platygastridae
Platygastridae, a family of minute (1-2 mm) platygastrid parasitoid wasps in Platygastroidea, about 2,100 species in 70 genera, mostly koinobiont endoparasitoids of gall midges, whiteflies, and planthoppers.
Platynereis dumerilii
Platynereis dumerilii, a marine bristle worm (Nereididae, Errantia) described in 1834, is a laboratory model for evo-devo, neurobiology, chronobiology, and regeneration, with lunar-synchronized reproduction, a ~1 Gbp genome, and a larval connectome.
Platypus
Platypus (Ornithorhynchus anatinus), duck-billed platypus: an egg-laying monotreme mammal endemic to eastern Australian waterways, with electroreceptive bill, venomous male ankle spurs, and IUCN Near Threatened status.
Platypus venom
Platypus venom: toxin of the male platypus (Ornithorhynchus anatinus), made in crural thigh glands and delivered via hind-leg spurs; causes months-long excruciating pain, unlike any other mammal venom.
Platyrrhinus
Platyrrhinus (broad-nosed bats), genus Saussure 1860 of Neotropical leaf-nosed fruit bats (Phyllostomidae), Mexico to Argentina; 14–21 species, Brazilian Shield origin, sister genus Vampyrodes.
Platyskinos Tholos Tomb
Platyskinos tholos tomb, Achladia (Sitia), East Crete: large looted LM IIIA2-B tholos tomb of cyclopean masonry excavated by Platon, holding three decorated larnakes, linked to a local Mycenaean-era elite.
Platyspondylic dysplasia, Torrance type
Platyspondylic dysplasia, Torrance type (PLSD-T, Torrance-Luton type) is a rare autosomal dominant lethal skeletal dysplasia caused by COL2A1 C-propeptide mutations, with severe limb shortening, platyspondyly, short ribs, and hypoplastic ilia; rare survivors reach adulthood.
Platystomatidae
Platystomatidae, the signal flies or picture-winged flies, is a tephritoid fly family of about 1,200 species in 120 genera, worldwide but richest in Australasia, with four subfamilies and debated monophyly.