All articles starting with P
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Parablechnum wattsii
Parablechnum wattsii (hard water-fern), formerly Blechnum wattsii Tindale 1963, is a Blechnaceae fern native to eastern and southeastern Australia (NSW, Queensland, South Australia, Tasmania, Victoria), moved to Parablechnum in 2016.
Parables of Jesus
The parables of Jesus, also called the parables of Christ, are short teaching stories in the Synoptic Gospels that use everyday scenes to convey religious lessons.
Parabola
A parabola is a plane curve of points equidistant from a fixed focus and a fixed line, the directrix; it is the conic section with eccentricity exactly 1.
Parabolic Anderson model
The parabolic Anderson model is the heat equation with a random potential, modeling electron conduction in defective crystals and known for intermittency, where mass concentrates on rare peaks.
Parabolic antenna
A parabolic antenna, also called a dish antenna, uses a parabolic reflector to focus radio waves, giving high gain for satellite, radar, and radio telescope use.
Parabolic dish concentrator
A parabolic dish concentrator is a dish-shaped solar collector that focuses sunlight onto a receiver at its focal point, holding the highest recorded CSP efficiency, 31.25 percent.
Parabolic reflector
A parabolic reflector, also called a parabolic mirror or parabolic dish, reflects parallel rays through a single focus, making it standard for satellite dishes, headlamps, and telescopes.
Parabolic trough
A parabolic trough is a line-focus concentrating solar power system in which long parabolic mirrors focus sunlight onto a receiver tube, heating a fluid that drives a turbine to generate electricity.
Parabolized stability equations
The parabolized stability equations (PSE), introduced by Thorwald Herbert and Fabio Bertolotti in the 1980s, compute the downstream growth of small disturbances in boundary-layer flows for transition prediction.
Paraboloid
A paraboloid is a quadric surface with two types, the bowl-shaped elliptic and the saddle-shaped hyperbolic, whose vertical cross sections are parabolas; elliptic paraboloids serve as reflecting antennas and telescopes.
Parabuteo
Parabuteo (Harris' Hawks) is a small Accipitridae hawk genus with two Neotropical species, Harris's Hawk and White-rumped Hawk, known for cooperative group hunting and a proposed species split.
Paracanoe
Paracanoe, also written Para canoe, is a Paralympic flatwater paddling discipline in which athletes with physical impairments race kayaks and va'a outrigger canoes over 200 meters.
Paracanthurus
Paracanthurus, monotypic surgeonfish genus of Acanthuridae holding the blue tang or palette surgeonfish, Paracanthurus hepatus (Linnaeus, 1766); Indo-Pacific reef fish, sister to Zebrasoma, venomous caudal spine, IUCN Least Concern.
Paracas culture
The Paracas culture was a pre-Columbian society on Peru's south coast, flourishing from about 800 BCE to 200 CE and known for its funerary textiles.
Paracas Textile
The Paracas Textile is a Nasca ceremonial mantle of about 100–300 C.E., held by the Brooklyn Museum since 1938, with a border of ninety three-dimensional figures.
Paracas textiles
Paracas textiles are embroidered and woven cloths made by the Paracas culture on Peru's southern coast between roughly 700 BC and 200 AD, best known as mummy wrappings.
Paracel Islands
Paracel Islands (Hoang Sa, Xisha): about 130 South China Sea features 300 km southeast of Hainan, claimed by China, Taiwan, and Vietnam, occupied by the PRC since its January 1974 battle with South Vietnam.
Paracelsian
Paracelsian is a rare barium feldspar mineral, the dimorph of celsian, first described in 1905 from Candoglia, Italy, and best known from the Benallt Mine in Wales.
Paracelsus
Paracelsus (Theophrastus von Hohenheim, 1493–1541) was a German-Swiss physician-alchemist who rejected Galenic medicine, introduced chemical therapy and dosing, founded occupational toxicology, and, per recent scholarship, practiced metallic transmutation.
Paracentesis
Paracentesis is needle or cannula drainage of ascitic fluid from the peritoneal cavity, done diagnostically (SBP, SAAG) or therapeutically; ultrasound guidance cuts bleeding complications, and >5 L removal requires albumin infusion.
Paracentrotus lividus
Paracentrotus lividus, the purple sea urchin, is an edible Mediterranean and NE Atlantic echinoid harvested for roe, a key grazer causing urchin barrens, declining ~5.8%/yr, and a developmental biology model organism.
Paraceratherium
Paraceratherium (syn. Indricotherium, Baluchitherium), a hornless giant rhinocerotoid from the Oligocene of Central and South Asia, 34–23 Ma; among the largest land mammals ever at about 11 tonnes mean, 15–20 tonnes maximum, 4.8 m shoulder height.
Paraceratites
Paraceratites is an extinct Anisian (Middle Triassic) ceratitid ammonoid genus of the family Ceratitidae, type species P. elegans, an index fossil with a Paraceratites trinodosus zone in Eurasia and North America.
Paracervical block
A paracervical block is a regional anesthesia technique in which local anesthetic injected beside the cervix numbs the cervix and lower uterus, used for IUD insertion, hysteroscopy, and brachytherapy.
Paracetamol
Paracetamol (acetaminophen, APAP, Tylenol) is a first-line analgesic and antipyretic synthesized in 1878, marketed from 1955, metabolized mainly via glucuronidation, and a leading cause of acute liver failure in overdose.
Paracetamol poisoning
Paracetamol (acetaminophen) poisoning: liver injury from overdose via NAPQI-mediated glutathione depletion. Managed with the Rumack-Matthew nomogram, activated charcoal, and N-acetylcysteine, the antidote most effective within 8 hours.
Parachela (tardigrade)
Parachela is the largest order of eutardigrade water bears, defined by two double claws per leg, sister to Apochela, containing Macrobiotoidea, Hypsibioidea, Isohypsibioidea, Eohypsibioidea and model species like Hypsibius exemplaris.
Parachute
A parachute is a fabric device that slows the descent of people or objects by drag, serving skydiving, military airdrop, emergency escape, and spacecraft recovery.
Parachute (2024 TV series)
Parachute (பாராசூட்) is a 2024 Tamil drama thriller web series on Disney+ Hotstar/JioHotstar, directed by Rasu Ranjith, starring Kishore, Kani Thiru, Krishna, and child actors Shakthi Rithvik and Iyal; five 30-minute episodes about two missing siblings, distinct from the 2024 Brittany Snow film Parachute.
Parachute (Hayley Williams song)
"Parachute" is a 2025 song by Hayley Williams, the previously unreleased closing track of Ego Death at a Bachelorette Party referencing her first marriage; it won the 2026 Grammy for Best Alternative Music Performance.