All articles starting with P
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PCI-X
PCI-X (PCI Extended) is a parallel computer expansion bus standard extending PCI with higher clock speeds and a split-transaction protocol, announced by Compaq, Hewlett-Packard, and IBM in 1998.
PCLinuxOS
PCLinuxOS: rolling-release, RPM-based Linux distribution for x86_64, forked from Mandrake 9.2 in October 2003 by Texstar; live-installable ISOs (KDE, MATE, Xfce), apt-rpm moving to DNF, own 12,000-package repository.
PCloud
pCloud is a Swiss cloud storage service founded in 2013 and registered in Baar, Switzerland, offering file storage, sync, sharing, backup, media streaming, and a paid client-side encrypted folder.
PCLS study
Pennington Center Longitudinal Study (PCLS, NCT00959270): prospective cohort at Pennington Biomedical Research Center, Baton Rouge, studying obesity, activity, and diet against chronic disease and mortality; ~30,000 enrollees; found visceral fat predicts death in whites.
PCM-EVW-ES study
PCM-EVW-ES (Perfil Clínico y Molecular de la Enfermedad de von Willebrand en España) is a Spanish multicenter VWD registry begun in 2010 that used NGS of VWF in 556 individuals, diagnosing 480 patients and identifying 704 variants, 155 novel.
PCN-222
PCN-222, also known as MOF-545, is a highly stable, mesoporous zirconium-porphyrin metal-organic framework reported in 2012 by Hong-Cai Zhou and colleagues at Texas A&M University as a biomimetic catalyst.
PCNA
PCNA (proliferating cell nuclear antigen) is the eukaryotic DNA sliding clamp, an 86 kDa homotrimeric ring loaded by RFC that tethers DNA polymerases and repair enzymes to DNA; also a 34 kDa SLE autoantigen.
PCO2
PCO2, or PaCO2, is the partial pressure of carbon dioxide dissolved in arterial or venous blood, normally 35 to 45 mmHg, and a marker of alveolar ventilation.
PCP (complexity class)
PCP(r, q) is a complexity class of languages checkable by a probabilistic verifier using O(r) random bits and O(q) proof queries; the PCP theorem states NP equals PCP(O(log n), O(1)).
PCP (complexity)
PCP, or probabilistically checkable proof, is a proof format for NP statements that a randomized verifier can check by reading only a few positions of the proof.
PCP theorem
The PCP theorem is a result in computational complexity theory stating that NP equals PCP(log n, 1), so NP proofs can be verified by reading constant bits.
PCPr
PCPr (N-propyl-1-phenylcyclohexylamine), also known as phencyclamine or NPPCA, is a dissociative arylcyclohexylamine of the PCP family, seized in Germany in the late 1990s and controlled there since 1997.
PCR screening
PCR screening uses the polymerase chain reaction to test many individual samples, such as bacterial colonies or mouse biopsies, for a target DNA sequence or genotype without purifying DNA first.
PCR-GLOBWB
PCR-GLOBWB (PCRaster Global Water Balance) is an open-source global hydrology and water resources model developed at Utrecht University in the Netherlands, simulating soil moisture, groundwater, and human water use at daily time steps.
PCSK5
PCSK5, also called PC5/6 or proprotein convertase 5/6, is a human gene on chromosome 9 encoding a basic amino acid-specific serine endoprotease with secreted (PC5A) and membrane (PC5B) isoforms; its mouse knockout is lethal, and Gdf11 is its likely specific substrate.
PCSK6
PCSK6, also called PACE4 or SPC4, is a human gene on chromosome 15q26.3 encoding a secreted calcium-dependent serine protease of the PCSK family that activates substrates like corin, Nodal, and ADAMTS-4/5, with roles in embryonic left-right patterning, blood pressure, osteoarthritis, and atherosclerosis.
PCSK7
PCSK7 (PC7, PC8, LPC) encodes a type-I membrane-bound proprotein convertase, the seventh of nine PCSK serine proteases, that also nonenzymatically escorts apolipoprotein B secretion, making it a candidate target in MASLD and dyslipidemia.
PCSK9
PCSK9, or proprotein convertase subtilisin-kexin type 9, is a serine protease identified in 2003 that is secreted mainly by the liver and degrades LDL receptors, raising LDL cholesterol and making it a major drug target.
PCSX-Reloaded
PCSX-Reloaded (PCSXR, PCSX-r) is an open-source, plugin-based PlayStation 1 emulator for PC, forked from the discontinued PCSX. Known for its HLE BIOS, PSEmu Pro plugins, the ARM-optimized PCSX ReARMed fork used in Sony's PlayStation Classic, and the PGXP graphics fork.
PCSX2
PCSX2 is a free, open-source PlayStation 2 emulator for Windows, Linux, and macOS, started in 2002 by the PCSX team, GPL v2 licensed, requiring a user-dumped PS2 BIOS, with about 98% of the library playable.
PCT Gazette
PCT Gazette: the weekly electronic publication of WIPO's International Bureau in English and French listing each published PCT international application, fee schedules, and Official Notices; paper edition ended July 2006, now on PATENTSCOPE.
PCU (film)
PCU is a 1994 American college comedy directed by Hart Bochner, written by Wesleyan alumni Adam Leff and Zak Penn, satirizing political correctness at fictional Port Chester University; a box office bomb that became a cable cult classic.
PD controller
A PD controller, or proportional-derivative controller, is a feedback control strategy combining a term proportional to error with one proportional to its rate of change.
PD-1 and PD-L1 inhibitors
PD-1 and PD-L1 inhibitors are immune checkpoint blocker antibodies (nivolumab, pembrolizumab; atezolizumab, durvalumab, avelumab) that restore T-cell killing of PD-L1-expressing tumors; first FDA-approved 2014, 2018 Nobel recognized.
PD-L1
PD-L1 (B7-H1, CD274) is a cell-surface ligand of the PD-1 receptor that suppresses T cell activity and is exploited by tumors for immune evasion; tumor PD-L1 IHC (22C3 TPS/CPS, SP263 assays) predicts response to checkpoint inhibitors.
Pd–Cu single-atom alloy catalysts for semihydrogenation
Pd–Cu single-atom alloy catalysts are heterogeneous catalysts in which isolated palladium atoms in a copper surface split hydrogen while copper carries out selective semihydrogenation of alkynes to alkenes.
PDC European Tour
PDC European Tour: series of Professional Darts Corporation ranking darts tournaments across continental Europe, staged by PDC Europe since 2007; 48-player events counting toward the Order of Merit and European Championship qualification.
PDC Order of Merit
PDC Order of Merit (Werner Rankings Ladder): the Professional Darts Corporation's world darts ranking, a rolling two-year prize-money list (£1 = 1 point) governing qualification, seeding, and Tour Card retention.
PDC World Darts Championship
PDC World Darts Championship, also WDC World Darts Championship, the Professional Darts Corporation's annual 501-format world title event held since 1994 at Alexandra Palace, London; 128 players, £5m prize fund, Sid Waddell Trophy.
PDCA
PDCA, also called the Shewhart cycle or Deming cycle, is a four-step Plan-Do-Check-Act cycle for continuous improvement, derived from the scientific method and shaped by Walter Shewhart and W. Edwards Deming.