All articles starting with P
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Plasma-catalytic ammonia synthesis
Plasma-catalytic ammonia synthesis makes ammonia by combining gas-discharge plasma with a catalyst, activating nitrogen at room temperature and atmospheric pressure as a milder alternative to Haber–Bosch.
Plasma-catalytic CO2 conversion
Plasma-catalytic CO2 conversion is a chemical technology combining non-thermal plasma with a catalyst to convert carbon dioxide into carbon monoxide, methane, methanol, and other value-added chemicals.
Plasma-catalytic CO2 conversion to syngas
Plasma-catalytic CO2 conversion to syngas combines non-thermal plasma discharges with solid catalysts to split CO2 or reform it with methane or hydrogen into CO/H2 mixtures for Fischer-Tropsch or methanol synthesis.
Plasma-enhanced atomic layer deposition
Plasma-enhanced atomic layer deposition (PE-ALD), also called plasma-assisted ALD, is a thin-film deposition variant using plasma reactants, enabling growth at much lower temperatures than thermal ALD.
Plasma-enhanced chemical vapor deposition
Plasma-enhanced chemical vapor deposition (PECVD) is a thin-film deposition method in which plasma dissociates precursor gases, depositing films at 200–400 °C instead of the 800–2000 °C thermal CVD requires.
Plasma-facing material
Plasma-facing material, also known as plasma-facing components (PFM), is the armor lining a fusion device's first wall, limiters, and divertor targets, governing tritium retention and component lifetime.
Plasma-immersion ion implantation
Plasma-immersion ion implantation (PIII) is a surface-modification method in which a workpiece immersed in plasma is pulsed to high negative voltage, implanting ions into all exposed surfaces.
Plasmablast
Plasmablast (plasmablasts, antibody-secreting cells): short-lived, proliferating B cell intermediates that secrete antibody during early immune responses, marked CD27+CD38highCD20low, peaking in blood at day 6–7, precursors of long-lived bone marrow plasma cells.
Plasmablastic lymphoma
Plasmablastic lymphoma (PBL) is a rare, very aggressive CD20-negative large B-cell non-Hodgkin lymphoma, first described in 1997 in the oral cavity of HIV-infected patients, marked by a plasma cell immunophenotype, EBV association, and frequent MYC rearrangements.
Plasmacytoid dendritic cell
Plasmacytoid dendritic cells (pDCs, CL:0000784), also called interferon-producing cells or DC2, are rare CD123-positive dendritic cells that rapidly secrete large amounts of type I interferon via TLR7/9-IRF7 signaling, and are central to antiviral immunity, lupus, and cancer immunobiology.
Plasmacytoma
Plasmacytoma, also called solitary plasmacytoma (SBP or EMP), is a rare single-site clonal plasma cell tumor with under 10% marrow involvement, treated mainly with 40-50 Gy radiotherapy and carrying a 14-38% three-year risk of progression to multiple myeloma.
Plasmalemma vesicle-associated protein
PLVAP (PV-1), plasmalemma vesicle-associated protein, is an endothelial-specific type II transmembrane glycoprotein forming fenestral and stomatal diaphragms that filter vascular permeability; its loss causes protein-losing enteropathy.
Plasmalogen
Plasmalogens are vinyl-ether glycerophospholipids, about 15-20 mol% of human membrane phospholipids, synthesized in peroxisomes; deficiency causes RCDP and marks Alzheimer's, cardiometabolic disease, and cancer.
Plasmalogen biosynthesis
Plasmalogen biosynthesis: the pathway making plasmalogens (vinyl-ether glycerophospholipids, plasmenyl lipids), initiated in peroxisomes (GNPAT, AGPS, FAR1) and completed in the ER (TMEM189), feedback-regulated, and linked to RCDP and cholesterol metabolism.
Plasmapause
The plasmapause is the outer boundary of Earth's plasmasphere, the sharp edge where cold plasma density drops steeply, typically 2 to 6 Earth radii out, discovered in the early 1960s and key to radiation belt physics.
Plasmapheresis
Plasmapheresis (therapeutic plasma exchange, TPE): extracorporeal separation and removal of blood plasma, by centrifugation or membrane filtration, to treat antibody-mediated diseases; ASFA categories I–IV guide use, typically 1–1.5 plasma volumes over 5–6 sessions.
Plasmaron
A plasmaron is a composite quasiparticle, an electron or hole bound to a plasmon, predicted by Lars Hedin in 1967 and first seen in doped graphene in 2010.
Plasmatics
Plasmatics: New York punk-metal band formed 1977 by Wendy O. Williams and Rod Swenson, debuted at CBGB 1978, albums New Hope for the Wretched through Maggots, banned in London, 1981 Milwaukee obscenity trial.
Plasmatocyte
Plasmatocyte: the dominant phagocytic hemocyte of Drosophila (90–95% of blood cells), macrophage-like, engulfing microbes and apoptotic debris; distinct from the capsule-forming lepidopteran cell of the same name.
Plasmaviridae
Plasmaviridae is an ICTV family of enveloped, pleomorphic bacterial viruses (genus Plasmavirus) with circular supercoiled dsDNA of 11,965 bp, infecting Acholeplasma; Acholeplasma virus L2 is the only classified species, released by budding without lysis.
Plasmepsin
Plasmepsins (PM I–X) are aspartyl proteases of Plasmodium malaria parasites; digestive-vacuole PMs I–IV degrade hemoglobin but are non-essential, while PMV, PMIX, and PMX are essential antimalarial drug targets, and pfpm2/3 copy number marks piperaquine resistance.
Plasmid
A plasmid is a small, generally circular DNA molecule in bacteria and other microbes that replicates independently of the chromosome, spreading antibiotic resistance and serving as a cloning vector.
Plasmid design
Plasmid design is the bench-biology practice of planning a circular DNA vector for its intended function, choosing an origin of replication, promoter, and selectable marker for cloning or protein production.
Plasmid Fertility inhibition factor
Plasmid fertility inhibition (fin), exemplified by the FinOP system, represses conjugative transfer: FinO protein stabilizes the 79-nt antisense RNA FinP, which blocks traJ mRNA translation; F plasmid finO is IS3-inactivated, so F transfers constitutively.
Plasmid preparation
Plasmid preparation (plasmid miniprep/maxiprep) isolates plasmid DNA from E. coli by alkaline lysis followed by silica membrane, anion-exchange, or magnetic-bead purification, with clinical grades limited to 97% supercoiled ccc plasmid.
Plasmid replication initiator protein TrfA
TrfA (trans-acting factor A) is the plasmid-encoded replication initiator of IncP-1 plasmids such as RK2; it binds iterons at oriV, exists as TrfA-44/TrfA-33 isoforms, controls copy number by handcuffing, and shapes plasmid host range.
Plasmid transfer regulator TraJ
TraJ, plasmid transfer regulator of the F sex factor and F-like plasmids in E. coli: primary activator of the 33-kb tra operon from the P_Y promoter, countering H-NS silencing with ArcA, itself repressed by FinOP and Hfq.
Plasmid virulence SpvD, Salmonella
SpvD, Salmonella plasmid virulence effector (spvD gene, pSLT plasmid), a 216-amino-acid SPI-2-translocated cysteine protease that blocks NF-κB p65 nuclear import via Xpo2, suppressing inflammation.
Plasmin
Plasmin: fibrin-degrading serine protease of the fibrinolytic system, generated from liver-made plasminogen (791 aa, ~180 μg/mL) by tPA and uPA cleavage at Arg561-Val562; inhibited by alpha2-antiplasmin and PAI-1; basis of thrombolytic therapy.
Plasminogen activator inhibitor-1
Plasminogen activator inhibitor-1 (PAI-1, serpin E1, SERPINE1) is the primary serpin inhibitor of t-PA and u-PA in fibrinolysis, a 45-kDa labile protein stabilized by vitronectin, linked to thrombosis, metabolic disease, cancer, and senescence, with no approved targeted drugs.