All articles starting with P
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Proposed provinces of the Philippines
Proposed provinces of the Philippines are campaigns to split existing provinces into new first-tier local government units, requiring a plebiscite after Congress passes a law.
Proposed second Scottish independence referendum
IndyRef2: proposed second Scottish independence referendum after the 2014 No vote (55.3-44.7). Requires a section 30 order; blocked by the UK Government and the 2022 UK Supreme Court ruling.
Proposed states and union territories of India
Proposed states and union territories of India: regions seeking separate statehood or UT status under Article 3, including Vidarbha, Gorkhaland, Bodoland, and Ladakh's statehood and Sixth Schedule demands, after Telangana (2014) was the last new state.
Proposed states of Brazil
Proposed states of Brazil are plans, repeatedly introduced in Congress, to create new states from existing ones; around 18 proposals have been discussed, including Tapajós and Carajás.
Proposed subsea strait crossings
Proposed subsea strait crossings are road or rail tunnel megaprojects beneath sea straits that were seriously studied but mostly never built, covering Fehmarnbelt, Gibraltar, Messina, and Bering; only the Fehmarnbelt immersed tunnel is under construction.
Proposed Tampa Bay Rays stadium
The proposed Tampa Bay Rays stadium is a planned fixed-roof ballpark on the Hillsborough College Dale Mabry campus in Tampa, Florida, targeted to open for Opening Day 2029.
Proposed treaties
A proposed treaty is a drafted but unsigned treaty, covering drafts under negotiation, adopted drafts never opened for signature, and abandoned proposals; multilateral negotiations average about 900 days.
Proposed tunnels in Africa
Proposed tunnels in Africa are tunnel schemes still at the study or concept stage, led by the Morocco–Spain rail tunnel under the Strait of Gibraltar, jointly studied since 1980.
Proposed United States invasion of Venezuela
Proposed United States invasion of Venezuela: a plan debated from 2017 to 2025 to depose Nicolás Maduro by force, involving Caribbean naval buildup, War Powers and UN Charter disputes, and the January 3, 2026 capture operation.
Proposition
Proposition: in philosophy, the sharable object of beliefs and the primary bearer of truth and falsity, also called sentence meanings or that-clause referents; central theories include Fregean, Russellian, structured, and possible-worlds accounts.
Proposition Joe
Proposition Joe (Joseph Stewart) is an East Baltimore drug kingpin in HBO's The Wire, played by Robert F. Chew. Known for the catchphrase "I've got a proposition for you," the New Day Co-Op co-founder appears in 24 episodes across all five seasons.
Propositional calculus
A propositional calculus is a formal proof system for propositional logic, given by axioms and inference rules such as modus ponens; first axiomatized by Frege in 1879, it is sound and complete.
Propositional dynamic logic
Propositional dynamic logic (PDL) is a modal logic for reasoning about programs, in which [α]A means A holds after every execution of program α. Fischer and Ladner defined it in 1979.
Propositional logic
Propositional logic, also known as sentential logic or sentential calculus, studies reasoning with whole propositions that are true or false, joined by connectives like and, or, and if-then.
Propositional proof system
A propositional proof system is any polynomial-time computable function whose range is exactly the propositional tautologies, the abstract definition by Cook and Reckhow in 1979 that founded proof complexity.
Propoxur
Propoxur (Baygon), CAS 114-26-1, is an N-methylcarbamate insecticide introduced in 1959 that inhibits acetylcholinesterase. Banned for plant protection in the EU since 2002; US pet-collar uses cancelled in 2013.
Propoxycaine
Propoxycaine (CAS 86-43-1) is a discontinued ester-type local anesthetic, C16H26N2O3, once combined with procaine in dental cartridges (Ravocaine) and withdrawn from the US market in 1996.
Propoxycarbazone
Propoxycarbazone is a selective, systemic herbicide used to control grassy weeds in cereal crops, applied commercially mainly as its sodium salt, propoxycarbazone-sodium.
Propranolol
Propranolol (Inderal) is a nonselective beta blocker developed by James Black at ICI, 1958–1964, introduced 1965 as the first clinically useful beta blocker; used for angina, hypertension, arrhythmia, migraine, and tremor; Nobel Prize 1988.
Proprietary estoppel
Proprietary estoppel, an English equitable doctrine, enforces assurances of a property interest where the claimant reasonably relies to their detriment; key cases include Thorner v Major [2009] UKHL 18 and Guest v Guest [2022] UKSC 27.
Proprietary software
Proprietary software, also known as closed-source software, is software whose source code and redistribution rights are restricted by its owner, in contrast to free and open-source software.
Proprietary trading
Proprietary trading, or prop trading, is when a financial firm trades securities, derivatives, or currencies with its own capital for its own profit, not for clients.
Proprioception
Proprioception (Sherrington's term, 1906) is the body-position, movement, and force sense from muscle spindles, Golgi tendon organs, joint, and skin receptors; tested by TTDPM, JPR, AMEDA, and trainable for sport.
Proprotein convertase 1
Proprotein convertase 1 (PC1/3, PCSK1, NEC1) is a neuroendocrine serine protease that cleaves prohormones such as POMC, proinsulin, and proglucagon; biallelic loss-of-function mutations cause rare monogenic obesity treated with setmelanotide.
Proprotein convertase 2
Proprotein convertase 2 (PC2, PCSK2, neuroendocrine convertase 2) is a subtilisin-like serine protease on human chromosome 20p11.2 that processes prohormones at paired basic residues, requires the 7B2 chaperone, and cleaves proglucagon to glucagon.
Proprotein convertase inhibitors and enzymology
Inhibitors of the proprotein convertases, a family of serine proteases, span synthetic active-site ligands like Dec-RVKR-CMK and MI-1148 and protein inhibitors including prodomains, proSAAS, and serpin B8, with potencies from picomolar to nanomolar.
Proprotein convertases in disease
Proprotein convertases in disease: nine secretory serine proteases (PC1–PC7, furin, SKI-1, PCSK9) whose dysregulation drives cancer, atherosclerosis, diabetes, and infections; PCSK9 inhibitors are approved therapies.
ProPublica
ProPublica is an independent, nonprofit American investigative newsroom founded 2007–2008 by the Sandler Foundation under Paul Steiger, donor-funded, co-publishing free stories with partner outlets, winner of nine Pulitzer Prizes including the 2025 Public Service prize.
Propulsive efficiency
Propulsive efficiency is the fraction of an engine's mechanical power that does useful work propelling a vehicle, rather than being wasted as kinetic energy in the exhaust.
Propulsive landing
A propulsive landing is one in which a spacecraft or rocket stage fires its own rocket engines against the direction of travel to slow down and touch down.