All articles starting with P

Physiology & behavior

Physiology & Behavior is a peer-reviewed academic journal published by Elsevier that covers the causal physiological mechanisms of behavior; it was founded in 1966 by Pergamon Press.

Physiology of cold adaptation in archaea

Physiology of cold adaptation in archaea describes the membrane restructuring, cold-active enzymes, and RNA chaperones that let archaeal cells grow at temperatures near 0 °C.

Physiology of pressure adaptation in archaea

Physiology of pressure adaptation in archaea, known as piezophily, covers the molecular mechanisms by which archaeal microbes grow under high pressure, such as membrane lipid adjustment.

Physiotherapists (physical therapists) are rehabilitation professionals treating functional decline through exercise, manual therapy, and physical modalities; title adopted 1966, global body World Physiotherapy (founded 1951) represents 600,000+ members.

Physiotherapy

Physiotherapy, or physical therapy, is the healthcare profession developing, maintaining and restoring movement and functional ability. Covers its World Physiotherapy definition, 1894 CSP origins, global workforce of 600,000+, primary care integration, and Cochrane evidence on exercise, manual therapy, and stroke rehabilitation.

Physisorption

Physisorption, also called physical adsorption, is adsorption in which van der Waals forces bind the adsorbate to a surface, in contrast to chemisorption, which forms chemical bonds.

Physoderma

Physoderma is a genus of over 100 fungal plant parasites in the phylum Blastocladiomycota, whose species live inside host tissues; P. maydis causes brown spot and stalk rot of maize.

Physonectae

Physonectae (Haeckel, 1888; synonym Physophorae) is a suborder of siphonophore hydrozoans with a pneumatophore float and nectosome of swimming bells; molecular phylogenies show it is paraphyletic, giving rise to Calycophorae within Codonophora.

Physostigmine

Physostigmine (eserine), a cholinesterase-inhibiting carbamate alkaloid from the Calabar bean, crosses the blood-brain barrier; used to reverse anticholinergic delirium, historically for glaucoma and myasthenia gravis; first synthesized by Percy Julian in 1935.

PhysX

PhysX, originally the NovodeX SDK of AGEIA Technologies, is a real-time physics simulation SDK developed by NVIDIA since its 2008 acquisition, used in Unity, Omniverse, robotics, and games, open source under BSD-3 since 2018.

Phytane

Phytane is a branched C20 isoprenoid alkane, 2,6,10,14-tetramethylhexadecane, derived mainly from the phytol side chain of chlorophyll and among the most widespread biomarkers in sediments and crude oils.

PHYTCOVID-19 trial

PHYTCOVID-19 (NCT04501965), a phase 2 three-arm open-label randomized trial in Conakry, Guinea, by the Institute for Research and Development of Medicinal and Food Plants of Guinea, comparing Cinchona-Stevia (CILE) and a four-plant powder (ACAR) against hydroxychloroquine, each with azithromycin, in 231 asymptomatic PCR-confirmed COVID-19 adults; no results posted.

Phytic acid

Phytic acid (InsP6, IP6, phytate) is the main phosphorus storage compound of seeds, 60–80% of seed phosphorus. It chelates iron, zinc, and calcium (antinutrient), resists monogastric digestion, and is reduced by soaking, fermentation, phytase, and low-phytate crops.

Phytium Technology

Phytium Technology (飞腾信息技术有限公司) is a Chinese CPU design company headquartered in Tianjin, founded in 2014 by China Electronics Corporation and Tianjin partners, that develops ARMv8-based processors and was added to the US Entity List in 2021.

Phytochelatin

Phytochelatins (PCs), (γ-Glu-Cys)n-Gly peptides, are enzymatically synthesized from glutathione by phytochelatin synthase in plants and some fungi, chelating cadmium, arsenic, and other metals for vacuolar sequestration and detoxification.

Phytochelatin synthase

Phytochelatin synthase (PCS, EC 2.3.2.15), a papain-like transpeptidase, synthesizes heavy-metal-binding phytochelatins (γ-Glu-Cys)n-Gly from glutathione and degrades glutathione conjugates in plants, fungi, algae, and some prokaryotes.

Phytochemical

Phytochemical (phytonutrient): biologically active plant secondary metabolite, over 200,000 known structures in six groups (polyphenols, terpenes, alkaloids, carotenoids, and others); studied for health effects, with mixed clinical-trial evidence.

Phytochrome

Phytochrome: red/far-red photoreceptor family (Pr/Pfr switch, bilin chromophore) regulating germination, de-etiolation, shade avoidance, and flowering in plants; discovered at USDA Beltsville, named 1960.

Phytoene

Phytoene is a colorless carotenoid hydrocarbon formed from two GGPP molecules by phytoene synthase, the biosynthetic precursor of carotenoids such as lycopene and beta-carotene that give fruits their colors.

Phytoene desaturase

Phytoene desaturase (PDS, EC 1.3.5.5), plant-type 15-cis-phytoene desaturase, a FAD-dependent plastid enzyme converting phytoene to tri-cis-zeta-carotene in carotenoid biosynthesis and the target of bleaching herbicides such as norflurazon and fluridone.

Phytoene synthase

Phytoene synthase (PSY, EC 2.5.1.32; bacterial CrtB) is the rate-limiting enzyme condensing two GGPP molecules into 15-cis-phytoene, the first committed step of carotenoid biosynthesis, and the main target of provitamin A crop biofortification such as Golden Rice.

Phytoestrogen

Phytoestrogens (plant estrogens, isoflavones, lignans, coumestans) are non-steroidal plant polyphenols that weakly bind estrogen receptors, mainly ERβ; used for menopausal symptoms, with modest hot flush reduction and generally favorable trial safety data.

Sep 29, 2026

Phytoextraction

Phytoextraction is a phytoremediation method in which plants take up heavy metals from contaminated soil and concentrate them in harvestable aboveground tissues, treated as hazardous waste or bio-ore.

Sep 29, 2026

Phytofiltration

Phytofiltration, also called rhizofiltration, is a phytoremediation method in which aquatic plants remove heavy metals, arsenic, and excess nutrients from contaminated water.

Phytolacca

Phytolacca (pokeweed, pokeroot, inkberry) is a genus of 27 accepted species in Phytolaccaceae, native to the Americas, Africa, Madagascar, and Asia; toxic, saponin-rich, with medicinal, dye, and molluscicidal uses.

Phytolacca americana

Phytolacca americana, American pokeweed or pokeberry, is a toxic perennial herb native to eastern North America, with black berry racemes, used as poke salad and ink, invasive in China and Europe.

Oct 20, 2026

Phytolaccaceae

Phytolaccaceae (pokeweed family), R.Br. 1818, nom. cons., a Caryophyllales flowering-plant family; broad sense 17 genera, 70–80 species, polyphyletic; strict sense Anisomeria, Ercilla, Phytolacca; type genus Phytolacca.

Oct 20, 2026

Phytolongin

Phytolongins (Phyl1.1, Phyl1.2, Phyl2.1, Phyl2.2) are non-SNARE longin domain proteins specific to land plants, derived from VAMP72, whose SNARE motif is replaced by a Phyl domain; they localize along the ER-to-plasma-membrane secretory pathway.

PHYTOME trial

PHYTOME trial (NCT04138654), a Maastricht University dietary intervention in the EU PHYTOME project: plant-extract-enriched, reduced-nitrite processed meats lowered fecal N-nitroso compound excretion in 63 volunteers.