All articles starting with P
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Per V. Bruel
Per V. Bruel, also known as Per Vilhelm Brüel, was a Danish acoustics engineer who co-founded the instrumentation company Brüel & Kjær in 1942 with Viggo Kjær.
Per Vilhelm Brüel
Per Vilhelm Brüel (1915–2015) was a Danish acoustics engineer who co-founded the instrumentation company Brüel & Kjær in 1942 and made sound and vibration measurement routine in industry.
Per Wahlöö
Per Wahlöö was a Swedish author and journalist who, with his partner Maj Sjöwall, wrote the ten Martin Beck detective novels that laid the foundation for Nordic noir.
Per Willy Guttormsen
Per Willy Guttormsen (born 1942, Narvik) is a Norwegian speed skater, nicknamed Bettong, who was fourth in the 5,000 m and 10,000 m at Grenoble 1968, 11th in the 10,000 m at Sapporo 1972, and set a 10,000 m world record of 15:16.1 at Inzell in March 1968.
Per- and polyfluoroalkyl substances
Per- and polyfluoroalkyl substances (PFAS), often called forever chemicals, are persistent fluorinated chemicals used since the 1940s in nonstick coatings and firefighting foam, and now regulated in drinking water.
Per-Gunnar Andersson (rally driver)
Per-Gunnar "P-G" Andersson, born 1980 in Årjäng, is a Swedish rally driver, two-time Junior WRC champion (2004, 2007), Suzuki WRC factory driver 2008, Proton SWRC runner-up 2010 and 2012, and multi-time Swedish rally champion.
Pêr-Jakez Helias
Pêr-Jakez Helias (Pierre-Jakez Hélias, 1914–1995) was a Breton-language author, ethnographer, teacher, and radio broadcaster whose Le Cheval d'orgueil (1975), rewritten by him in French, sold more than 2 million copies.
Per-Medjed
Per-Medjed, the Egyptian "House of Medjed" named for a sacred fish, is the Pharaonic name of the city later called Oxyrhynchus, capital of the 19th Upper Egyptian nome.
Per-Olof Åstrand
Per-Olof Åstrand (1922–2015), Swedish exercise physiologist, co-creator of the Åstrand-Ryhming nomogram and Åstrand submaximal cycle test, professor at GIH Stockholm and Karolinska Institutet, co-author of Textbook of Work Physiology.
Per-Olof Berggren
Per-Olof Berggren is a Swedish professor of experimental endocrinology at Karolinska Institutet in Stockholm, director of the Rolf Luft Research Center for Diabetes and Endocrinology, elected to the US National Academy of Medicine in 2016.
Per-oral endoscopic myotomy
Per-oral endoscopic myotomy (POEM) is an endoscopic procedure treating achalasia by dividing the lower esophageal sphincter muscle through a submucosal tunnel, with no skin incisions.
Per-protocol analysis
Per-protocol analysis is a clinical trial analysis including only participants who adhered to their assigned treatment; it is common in explanatory trials but can introduce selection bias.
Per-Ptah
Per-Ptah (pr-Ptḥ, "House of Ptah") is an ancient Egyptian term for a temple domain of the god Ptah, notably the great Ptah temple at Memphis (Mit Rahina) and the Ptah temple at Karnak.
Per-survivor processing
Per-survivor processing (PSP) is a digital communications technique in which each Viterbi survivor path carries its own channel estimate, jointly detecting data and estimating unknown parameters.
Per-Tau Shell
The Per-Tau Shell is a near-spherical cavity in the local interstellar medium, about 500 light-years wide, surrounding and connecting the Perseus and Taurus molecular clouds, revealed by 3D dust mapping in 2021.
Per-tone equalization
Per-tone equalization is the one-tap frequency-domain equalization method in OFDM receivers, where each subcarrier is corrected by a single complex multiplication using an estimated channel gain.
Per‐Henrik Groop
Per-Henrik Groop is a Finnish physician-scientist in endocrinology, diabetes, and metabolism at the University of Helsinki, known for founding the FinnDiane Study, a nationwide cohort of nearly 10,000 people with type 1 diabetes.
PER1
PER1 (period circadian regulator 1; aliases PER, hPER, RIGUI; Gene ID 5187) is a human Period-family clock gene, expressed rhythmically in the suprachiasmatic nucleus, repressing CLOCK-BMAL1 in the circadian feedback loop, light-inducible, and linked to tumor suppression.
PER2
PER2 (period circadian regulator 2), human gene at 2q37.3 encoding a PAS-domain transcriptional repressor of the circadian CLOCK-BMAL1 feedback loop; mutations cause familial advanced sleep phase syndrome and loss-of-function variants shift sleep earlier.
PER3
PER3 (period circadian regulator 3), also called FASPS3 or GIG13, is a human circadian clock gene on chromosome 1p36.23. Unlike PER1 and PER2 it is dispensable for the core clock but shapes sleep homeostasis; its 54-bp VNTR (4 or 5 repeats, rs57875989) is linked to morningness and sleep-loss vulnerability.
Peracetic acid
Peracetic acid, also called peroxyacetic acid, is an organic peroxide used as a sterilant, disinfectant, and bleaching agent, best known for sterilizing heat-sensitive medical instruments and disinfecting wastewater as a chlorine alternative.
Peradeniya school
The Peradeniya school was a movement in modern Sinhala literature that emerged from the University of Ceylon at Peradeniya, Sri Lanka, in the 1950s and 1960s.
Peraea
Peraea (Perea), from Greek peran "beyond," was the Jewish district east of the Jordan River, bounded by Machaerus, Pella, and Philadelphia; ruled by Herod Antipas, conquered by Vespasian in 67 CE, and emptied of Jewish settlement after the Bar Kokhba Revolt.
Perahu Kertas
Perahu Kertas ("Paper Boat") is a 1983 poetry collection by the Indonesian poet Sapardi Djoko Damono, published by Balai Pustaka, Jakarta, which won the Jakarta Arts Council Literary Prize.
Perak
Perak (Perak Darul Ridzuan) is a west-coast Malaysian state, capital Ipoh, population about 2.5 million. Sultanate founded 1528; Pangkor Treaty 1874 began British rule; services-led economy, 5.7% GDP growth in 2025.
Perak FA state football team
Perak FA (The Bos Gaurus), the Perak Football Association's state team from Ipoh, Malaysia; 2018 Malaysia Cup winners and 2006/07 Super League runners-up, now playing tier-two A1 Semi-Pro League football after a 2025 national licence failure.
Perak Sultanate
The Perak Sultanate is the hereditary Malay monarchy of Perak on Peninsular Malaysia's west coast, founded in 1528 and ruling continuously under Sultan Nazrin Muizzuddin Shah, the 35th Sultan.
Perak War
The Perak War (1875 to 1876) was an armed conflict between British forces and Malay leaders in Perak, triggered by the assassination of British Resident J.W.W. Birch.
Peralta
Peralta is a Mesoamerican archaeological zone near Abasolo, Guanajuato, Mexico, one of the largest El Bajío sites (c. 300–750 AD), with 20 architectural groups including El Divisadero and the Recinto de los Gobernantes, sunken-patio architecture, and unknown ethnic builders.
Peramivir anhydrous
Peramivir anhydrous (Rapivab, RAPIACTA) is a cyclopentane intravenous neuraminidase inhibitor for acute uncomplicated influenza; single 600 mg dose within 2 days of onset, FDA approved December 2014.