All articles starting with P
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Permissive hypotension
Permissive hypotension is a trauma resuscitation strategy that accepts systolic pressure below normal, typically 80–90 mmHg, until bleeding is controlled, and is excluded in patients with brain or spinal injury.
Permissive license
A permissive license is an open-source software license that allows free use, modification, and redistribution, including in proprietary works, with minimal obligations like retaining notices.
Permittivity
Permittivity, also called dielectric permittivity, is the material property relating electric displacement to electric field, D = εE; in vacuum it equals ε₀, about 8.854 × 10⁻¹² F/m.
Permodalan Nasional Berhad (PNB)
Permodalan Nasional Berhad (PNB) is a Malaysian government-linked investment company and fund manager, established in 1978 to raise Bumiputera equity ownership, managing RM364 billion in assets.
Permutation
A permutation is a rearrangement of the elements of a set, or a one-to-one mapping of a set onto itself; there are n! of n elements.
Permutation feature importance
Permutation feature importance, or permutation importance, is a model-agnostic machine learning technique, introduced by Leo Breiman in 2001, that measures feature importance by shuffling values and observing the drop in model performance.
Permutation group
A permutation group is a group whose elements are permutations of a set, with composition as the operation; by Cayley's theorem, every group is isomorphic to one.
Permutation matrix
A permutation matrix is a square matrix with exactly one 1 in each row and each column, representing permutations of n objects; multiplying by it reorders rows or columns.
Permutation model
A permutation model, also called a Fraenkel–Mostowski model, is a model of Zermelo–Fraenkel set theory with atoms built by symmetric groups of permutations, devised to prove the Axiom of Choice independent.
Permutation notation
Permutation notation is the collection of mathematical symbols for denoting and counting permutations, including the factorial n!, the count nPr, and two-line and one-line notations.
Permutation polynomial
A permutation polynomial is a polynomial over a finite field, usually, that induces a bijection on the field's elements, with applications in cryptography, coding theory, and combinatorial design.
Permutation representation
A permutation representation is a way of realizing a group's elements as permutations of a set, equivalently a group action of the group on that set.
Permutation test
A permutation test is a nonparametric method of hypothesis testing in which the observed test statistic is compared against the distribution obtained by rearranging, or permuting, the data.
Permutohedron
The permutohedron is a convex polytope whose vertices are all permutations of a vector with distinct coordinates, a higher-dimensional generalization of the hexagon central to geometric combinatorics.
PERN (company)
PERN S.A. is a Polish state-controlled oil and fuel logistics company headquartered in Płock, whose 2,558 km of pipelines supply refiners in Poland and Germany.
Perna canaliculus
Perna canaliculus (greenshell or green-lipped mussel; Māori kūtai) is a Mytilidae mussel endemic to New Zealand, farmed on longlines, ~80% reliant on Ninety Mile Beach wild spat, and sold as an osteoarthritis nutraceutical.
Perna perna
Perna perna, the brown mussel or Mexilhao mussel, a large Mytilidae bivalve native to the western Indian Ocean and west Africa, introduced to South America and the Gulf of Mexico; Perna indica is its synonym, and it is an Australian priority marine pest.
Perna viridis
Perna viridis, the Asian green mussel or green-lipped mussel, is an Indo-Pacific mytilid bivalve farmed for food, used as a biomonitor for metals, and invasive in Japan, the Caribbean, Florida, and Australia.
Pernambucan Revolution
The Pernambucan Revolution (Revolução Pernambucana) was a republican revolt that broke out in Recife in March 1817, overthrew Portuguese authorities, and held power for 75 days.
Pernambuco
Pernambuco is a state of Brazil on the northeastern coast, with Recife as its capital and 9 million inhabitants at the 2022 census. It has one of Brazil's largest state economies.
Perneb
Perneb was a Fifth Dynasty Egyptian palace administrator whose mastaba tomb at Saqqara, built ca. 2381–2323 BCE, has stood in New York's Metropolitan Museum of Art since 1916.
Pernell Roberts
Pernell Roberts (1928-2010), American stage and TV actor; Adam Cartwright on Bonanza (1959-1965) and star of Trapper John, M.D. (1979-1986); left Bonanza calling it junk TV.
Pernell Whitaker
Pernell "Sweet Pea" Whitaker (1964-2019), American boxer, 1984 Olympic gold medalist and four-division world champion; undisputed lightweight champion 1990; famous Chavez draw; 40-4-1 (17 KOs).
Pernicious anemia
Pernicious anaemia, also called Biermer's or Addisonian anaemia, is autoimmune gastritis causing loss of intrinsic factor and B12 deficiency; diagnosed via intrinsic factor and parietal cell antibodies, treated with lifelong B12 injections.
Pernilla August
Pernilla August (b. Mia Pernilla Wallgren, 13 February 1958, Stockholm) is a Swedish actress and director, a Bergman favorite who won Cannes Best Actress for The Best Intentions (1992), played Shmi Skywalker in Star Wars Episodes I and II, and directed Guldbagge-winning Beyond (2010).
Pernilla Wiberg
Pernilla Wiberg, Swedish alpine skier (born 1970, Norrköping), not the hockey player Pernilla Winberg: double Olympic champion 1992 GS and 1994 combined, four world titles, 24 World Cup wins, 1996-97 overall champion.
Pernille Blume
Pernille Blume, Danish sprint freestyle swimmer, born 1994 in Herlev; Olympic 50 m freestyle champion at Rio 2016 (24.07, Danish record), first Danish swimming gold since 1948; three Olympic medals; retired 2022.
Pernille Rørth
Pernille Rørth is a Danish molecular biologist who studies how cells migrate and divide during development using the fruit fly Drosophila, known for identifying tribbles as a cell cycle regulator.
Pernis
Pernis (honey-buzzards), genus of Accipitridae raptors named by Cuvier in 1816; includes P. apivorus and P. ptilorhynchus, wasp-larvae feeders; P. ptilorhynchus is the basal accipitrid lineage, with Aviceda as sister genus.
Pernod Ricard
Pernod Ricard is a French multinational producer of spirits and wine, created in 1975 by the merger of the anise-spirit houses Pernod and Ricard, ranked second worldwide behind Diageo.