All articles starting with P
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Poltava
Poltava (Полтава) is a Ukrainian city on the Vorskla River, administrative center of Poltava oblast, first recorded as Ltava in 1174 and famous for the 1709 battle where Peter I defeated Charles XII.
Poltava Oblast
Poltava Oblast (Полтавська область, Poltavshchyna), a central Ukrainian oblast created 22 September 1937 with capital Poltava; 28,748 km², chornozem soils, mining- and agriculture-based economy, and a major wartime host of over 184,000 displaced persons.
Poltava Raion
Poltava Raion (Полтавський район), a district of Poltava Oblast, Ukraine, centered on Poltava. Created 17 July 2020 in the raion reform; area 10,858.6 km², 24 hromadas, 746 settlements, population about 569,000-584,000.
Poltergeist
Poltergeist (German, "noisy ghost") denotes reported unexplained noises and object movements, often focused on one person; interpretations range from parapsychological RSPK to fraud and natural causes like standing air waves.
Poltergeist (1982 film)
Poltergeist is a 1982 American supernatural horror film directed by Tobe Hooper and produced by Steven Spielberg and Frank Marshall, in which spirits abduct a family's five-year-old daughter.
Poltergeist (2015 film)
Poltergeist is a 2015 American supernatural horror film directed by Gil Kenan and starring Sam Rockwell, a remake of the 1982 film about a family haunted by malevolent spirits.
Poltergeist (franchise)
Poltergeist is an American horror franchise of four films and one TV series centered on the Freeling family and the demon-led ghosts drawn to daughter Carol Anne. It began with the 1982 Tobe Hooper film produced by Steven Spielberg, followed by 1986 and 1988 sequels, a 2015 remake, and the unrelated Poltergeist: The Legacy series.
Poltergeist II: The Other Side
Poltergeist II: The Other Side (1986) is the first Poltergeist sequel, directed by Brian Gibson, written by Grais and Victor, starring JoBeth Williams, Craig T. Nelson, Heather O'Rourke, and Julian Beck as Reverend Kane; 91 min, PG-13, $19M budget, $38.8M US gross, 20% on Rotten Tomatoes.
Poltergeist III
Poltergeist III is a 1988 American supernatural horror film, the third and final entry in the original Poltergeist trilogy, directed by Gary Sherman, starring Heather O'Rourke, Tom Skerritt, Nancy Allen, and Zelda Rubinstein, set in a mirrored Chicago high-rise and released June 10, 1988.
Poludnitsa Dorsa
Poludnitsa Dorsa (Poludnista Dorsa), a 1,500-2,000 km long north-trending deformation belt of ridges and fractures in eastern Rusalka Planitia, Venus; IAU named 1997, studied by Young and Hansen (2005) from Magellan data.
Polvo Oil and Gas Field
The Polvo Oil and Gas Field is an offshore oil field in the Campos Basin, Brazil, about 100 kilometers east of Cabo Frio, producing since 2007.
Poly Developments & Holdings Group
Poly Developments & Holdings Group Co., Ltd. (保利发展控股集团股份有限公司) is a Chinese state-owned residential property developer, founded in 1992 and Shanghai-listed since 2006, the largest Chinese developer by contracted sales in 2024 and 2025.
Poly Panou
Poly Panou (Πόλυ Πάνου), born Polytimi Koliopanou in Athens in 1940, was a Greek laiko and rembetiko singer who died in Athens in 2013 at 73.
Poly Styrene
Poly Styrene (Marianne Joan Elliott-Said, 1957-2011) was the English singer-songwriter who fronted punk band X-Ray Spex, recorded Germ Free Adolescents (1978) and "Oh Bondage Up Yours!", and later made solo albums including Translucence and Generation Indigo.
Poly-N-isopropylacrylamide
Poly-N-isopropylacrylamide, abbreviated PNIPAM or PNIPAAm, is a synthetic thermoresponsive polymer that dissolves below about 32 °C and phase-separates above it, making it the most studied smart polymer for drug delivery, tissue engineering, and cell sheet harvesting.
Poly(2-oxazoline) drug conjugates
Poly(2-oxazoline) drug conjugates are polymer therapeutics in which drugs are attached to POx carrier polymers, improving solubility and tumor accumulation; developed as PEG alternatives, their clinical lead SER-252 targets Parkinson's disease.
Poly(A) polymerase I
Poly(A) polymerase I (PAP I, pcnB) is the main polyadenylating enzyme of E. coli, discovered in 1962. It adds destabilizing poly(A) tails to RNA 3' ends, tagging structured transcripts for PNPase and RNase II decay.
Poly(A)-binding protein
Poly(A)-binding protein (PABP, PABPC1; nuclear PABPN1) is an RNA-binding protein that binds mRNA poly(A) tails, forming a closed loop with eIF4G/eIF4E to enhance translation, control mRNA decay, and regulate polyadenylation.
Poly(A)-site sequencing
Poly(A)-site sequencing (PAS-seq) is a deep-sequencing method that maps polyadenylation sites across a transcriptome and quantifies RNA abundance, introduced by Peter J. Shepard and colleagues in 2011.
Poly(ADP-ribose) glycohydrolase
Poly(ADP-ribose) glycohydrolase (PARG) is the primary enzyme hydrolyzing poly(ADP-ribose) chains made by PARPs during DNA repair; a single-gene macrodomain hydrolase, upregulated in many cancers, and an emerging cancer drug target with inhibitors in early trials but no approval.
Poly(ADP-ribose) polymerase
Poly(ADP-ribose) polymerases (PARPs) are a family of 17 human enzymes that attach ADP-ribose to proteins; PARP1's role in DNA repair led to approved cancer drugs.
Poly(carboxybetaine) nanoparticles
Poly(carboxybetaine) nanoparticles are drug-delivery and imaging particles coated with the zwitterionic polymer poly(carboxybetaine), a PEG alternative whose hydrated surface resists protein adsorption and immune clearance.
Poly(ionic liquid)s
Poly(ionic liquid)s, also called polymerized ionic liquids, are a subclass of polyelectrolytes combining ionic liquid properties with polymer robustness, used in batteries, CO2 capture, and catalysis.
Poly(lactic-co-glycolic acid)
Poly(lactic-co-glycolic acid) (PLGA) is a biodegradable copolymer of lactic and glycolic acids, FDA-approved since the 1970s and now the leading polymer carrier for controlled drug delivery and resorbable surgical implants.
Poly(methyl methacrylate)
Poly(methyl methacrylate), or PMMA, sold under trade names including Plexiglas, Perspex, and Lucite, is a transparent thermoplastic acrylic valued for optical clarity, weather resistance, and light weight, used in signage, car lamps, and bone cement.
Poly(p-phenylene oxide)
Poly(p-phenylene oxide), also known as polyphenylene oxide or PPO, is an amorphous engineering thermoplastic made by oxidative coupling of 2,6-dimethylphenol, first reported by Hay in 1959 and commercialized in 1965.
Pólya conjecture
The Pólya conjecture is a 1919 statement in number theory asserting the summatory Liouville function is never positive. Brian Haselgrove disproved it in 1958, and the smallest counterexample, 906,150,257, was found in 1980.
Pólya enumeration theorem
The Pólya enumeration theorem, or Pólya enumeration formula, is a combinatorics result counting distinct colorings and configurations up to a symmetry group, generalizing Burnside's lemma through weighted generating functions.
Pólya tree prior
The Pólya tree prior is a Bayesian nonparametric prior on distribution functions, built by recursive binary splitting with independent Beta branching probabilities, used in density estimation and survival analysis.
Pólya urn model
The Pólya urn model, or Pólya's urn, is a stochastic process where drawn balls are returned with extra balls of the same color, reinforcing frequent colors.