All articles starting with P
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Paradox Interactive
Paradox Interactive is a Stockholm-based Swedish developer and publisher of strategy and management games (Europa Universalis, Crusader Kings, Stellaris, Hearts of Iron), known for its long-lived DLC-supported games, five internal studios, and World of Darkness ownership.
Paradox of hedonism
The paradox of hedonism, also called the paradox of happiness, holds that directly pursuing pleasure is self-defeating. Formulated by Joseph Butler (1726) and Henry Sidgwick, it challenges prudential hedonism about well-being.
Paradox of tolerance
Paradox of tolerance: Karl Popper's 1945 claim in The Open Society and Its Enemies that unlimited tolerance lets intolerance destroy tolerance, with his caveat that rational argument, not suppression, is the first response.
Paradox of youth (astronomy)
The paradox of youth is the problem of why massive young stars exist near Sagittarius A, the Milky Way's central black hole, despite tidal forces that should prevent star formation there.
Paradoxes of set theory
The paradoxes of set theory are contradictions from naive comprehension, including Russell's paradox (1901), Burali-Forti's (1897), and Cantor's, which forced set theory onto axiomatic foundations.
Paradoxical embolism
Paradoxical embolism, also called paradoxical embolization, is venous thrombus crossing a right-to-left shunt, usually a patent foramen ovale, into the arteries, causing stroke or limb ischemia; first described by Cohnheim in 1877.
Paradoxical intention
Paradoxical intention (PI), a logotherapy technique developed by Viktor Frankl, treats anticipatory anxiety by having patients intend what they fear; adapted by Ascher and Efran for insomnia, patients try to stay awake, reducing sleep performance anxiety.
Paradoxical reaction
Paradoxical reaction: an adverse drug effect opposite to the drug's expected pharmacological action, classically agitation or aggression from sedative benzodiazepines like midazolam, occurring in under 1% of patients and reversible with flumazenil.
Paradoxides
Paradoxides (Brongniart, 1822) is a genus of giant middle Cambrian trilobites (family Paradoxididae, order Redlichiida) reaching 60 cm, found in West Gondwana, Avalonia, Siberia, and Baltica, and used as an index fossil for the lower–middle Cambrian boundary.
Paradoxurus
Paradoxurus is a genus of Asian palm civets (family Viverridae, subfamily Paradoxurinae), including the Asian palm civet P. hermaphroditus, source of kopi luwak coffee, plus P. jerdoni and P. zeylonensis; nocturnal, arboreal, frugivorous seed dispersers.
Paraduodenal pancreatitis
Paraduodenal pancreatitis, also called groove pancreatitis, is a rare focal chronic pancreatitis of the pancreaticoduodenal groove, affecting middle-aged men with alcohol and smoking histories and mimicking pancreatic cancer on imaging.
Paraemheb
Paraemheb, also written Pra'emhab, was a vizier of Egypt who served under Amenmesse in the late Nineteenth Dynasty, around 1200 BC, during the succession struggle with Seti II.
Paraesophageal hernia repair
Paraesophageal hernia repair is a surgical operation that returns the stomach and other herniated organs from the chest into the abdomen and closes the diaphragmatic hiatus, usually done laparoscopically.
Paraetacae
Paraetacae, also called Paraetacene, was a rugged mountain district on the frontier between Media and Persis in the Zagros of western Iran, near the Bakhtyari mountains.
Paraetaceni
The Paraetaceni (Greek Παρητακηνοί) were a people of the mountain district of Paraetacene between Media and Persis, named by Herodotus as one of the six Median tribes.
Paraetonium/Ammonia
Paraetonium/Ammonia (Greek Paraitonion) was the westernmost town of ancient Egypt, a port city at modern Marsa Matruh, founded by tradition by Alexander, held by Antony, fortified by Justinian, and also the name of a Roman white pigment.
Parafermion
A parafermion is a quasiparticle in condensed matter physics that generalizes the Majorana fermion; introduced by Fradkin and Kadanoff, it is pursued for topological quantum computation but remains experimentally unconfirmed.
Parafermion zero mode
A parafermion zero mode, also called a fractionalized Majorana mode, is a non-Abelian anyon excitation generalizing the Majorana zero mode to Zn symmetry in topological phases.
Paraffin embedding
Paraffin embedding is a histology technique in which fixed tissue is infiltrated with molten paraffin wax, forming FFPE blocks cut into thin sections for microscopy.
Paraffin oil
Paraffin oil (mineral oil, CAS 8012-95-1 and 8042-47-5) is a refined petroleum hydrocarbon mixture used as horticultural spray oil, killing insects and mites by smothering, with EU approval renewed to 2041.
Paraffin wax
Paraffin wax, also known as petroleum wax, is a white, odorless waxy solid of straight-chain saturated hydrocarbons derived from petroleum, used in candles, packaging, cosmetics, and thermal energy storage.
Paraffinic Froth Treatment
Paraffinic froth treatment (PFT) is an oil sands bitumen cleaning process, first commercialized by Albian Sands in 2002, in which a paraffinic solvent precipitates asphaltenes from bitumen froth.
Paraflagellar rod
Paraflagellar rod (PFR), or paraxial rod: lattice-like extra-axonemal filament alongside the flagellar axoneme of kinetoplastids, euglenoids, and dinoflagellates; built from PFR1 and PFR2, essential for trypanosome motility and viability.
Parafollicular cell
Parafollicular cell (thyroid C cell): endocrine thyroid cell secreting calcitonin, which lowers serum calcium. Originates from pharyngeal endoderm via the ultimobranchial body, not neural crest; source of medullary thyroid carcinoma.
Paraformaldehyde
Paraformaldehyde is a low-molecular-weight linear polymer of formaldehyde with 8 to 100 units, a white solid used as a convenient formaldehyde source in industry and laboratories.
Parag Agrawal
Parag Agrawal is an Indian-American computer scientist and technology executive who served as CEO of Twitter from November 2021 until his dismissal in October 2022.
Parag Jain
Parag Jain (पराग जैन), 1989-batch IPS Punjab cadre officer, appointed June 2025 as Secretary of India's R&AW for a two-year term from July 1, 2025, succeeding Ravi Sinha; former ARC head credited with Operation Sindoor intelligence.
Parag Khanna
Parag Khanna, born 1977 in Kanpur, India, is a political scientist and geopolitical analyst whose books, including Connectography (2016), argue that connectivity, cities, and supply chains shape world politics.
Parag Pathak
Parag Pathak is an American economist at MIT who designs the centralized systems matching students to public schools, work recognized with the 2018 John Bates Clark Medal.
Paragal Khan
Paragal Khan (পরাগল খান) was a military commander and governor of Chittagong under the Bengal sultan Alauddin Husain Shah, appointed laskar after the 1512 occupation.