All articles starting with P
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Proechimys
Proechimys (spiny rats, J. A. Allen, 1899) is a genus of terrestrial Neotropical rodents in family Echimyidae, tribe Myocastorini; about 25 species, diploid numbers 14-62, not monophyletic as defined.
Proenkephalin A
Proenkephalin A (PENK, proenkephalin) is the 243-amino-acid precursor of the enkephalin opioid peptides, cloned in 1982, containing six Met-enkephalin and one Leu-enkephalin copies, and used clinically as a kidney function biomarker.
Proenkephalin B
Proenkephalin B, also called prodynorphin or pronorphin (UniProt P01213), is the opioid peptide prohormone yielding dynorphin A, dynorphin B, neoendorphins, and leumorphin, kappa-receptor-preferring peptides with Leu-enkephalin N-termini.
Proerna (Greece)
Proerna (Πρόερνα), ancient Thessalian city in Achaea Phthiotis near Neo Monastiri, Domokos, Fthiotida, Greece; identified with the Gynaikokastro Hellenistic acropolis, occupied from the Early Bronze Age, with a sanctuary of Demeter Proernia.
Proerythroblast
Proerythroblast (rubriblast, pronormoblast): the earliest recognizable nucleated red-cell precursor in bone marrow, CD71-positive, giving rise to basophilic, polychromatic, and orthochromatic erythroblasts during erythropoiesis.
Proetus
Proetus is a genus of small proetid trilobites established by Steininger in 1831 and serving as the namesake and type genus of Proetidae, the longest-lived and most diverse trilobite family.
Prof (rapper)
Prof is the stage name of Jacob Lukas Anderson, an American rapper, singer, and record producer based in Minneapolis, Minnesota, with his own label, Stophouse Music Group.
Prof. Dr. Nikolaus F. Rentschler
Nikolaus F. Rentschler (born 1963) is a German biotechnology entrepreneur, fifth generation of a family firm founded in 1872, who transformed Rentschler Biopharma SE into a biologics CDMO.
Profanity
Profanity: language showing disrespect for the sacred or taboo, from Latin profanus "not sacred". Also called swearing or cursing; draws on sex, bodily functions, religion, and family themes; distinctive sounds, brain processing, and pragmatic functions.
Profanity in American Sign Language
Profanity in ASL: taboo signs and non-manual emphasis used for swearing and insults in American Sign Language, a visual register with religion, sex, body-part, and excretion fields, rare modifiers, iconicity-driven offensiveness, and innovation among deaf teen signers.
Profenofos
Profenofos (CAS 41198-08-7), a moderately hazardous organophosphorus insecticide-acaricide developed by Ciba-Geigy, acts by acetylcholinesterase inhibition; used on cotton and vegetables, canceled in the US in 2018 and not EU-approved.
Profertil
Profertil S.A. is an Argentine agro-industrial company producing granulated urea and ammonia at a plant in Ingeniero White, Bahía Blanca, founded in 1996 and one of South America's largest granular urea producers.
Profession
Profession: an occupation distinguished from ordinary work by specialized knowledge, controlled training, and self-regulation. Central concept of the sociology of professions, studied through functionalist, interactionist, and conflict approaches since Durkheim and Weber.
Professional
Professional: a member of a profession, an occupation defined by specialized knowledge, self-regulation by a professional body, and public service commitment. Distinguished from ordinary occupations by certifying tests, codes of ethics, and guild-derived professionalization.
Professional Air Traffic Controllers Organization (1968)
The Professional Air Traffic Controllers Organization (PATCO) was a union of federal air traffic controllers, founded in 1968, whose 1981 strike led President Reagan to fire about 11,400 members.
Professional association
Professional association: also called professional society or professional body; a nonprofit organization of practitioners in a shared field. Functions include education, certification, ethics codes, standards, and advocacy; descended from medieval guilds.
Professional Association of Therapeutic Horsemanship
PATH Intl., formerly the North American Riding for the Handicapped Association (founded 1969, renamed 2011), is the US 501(c)3 standards, certification, and accreditation body for equine-assisted services, with 721 member centers and NCCA-accredited CTRI credential.
Professional associations of patent and trademark attorneys
Professional associations of patent and trademark attorneys are organizations that qualify, represent, and advocate for IP attorneys, beginning with London's Chartered Institute of Patent Agents in 1882.
Professional baseball
Professional baseball: paid, organized baseball, headed by MLB (30 clubs) above 120 affiliated MiLB teams and independent leagues; Negro Leagues history, 2026 ABS challenge system, and CBA salary-cap dispute.
Professional Baseball Spirits
Professional Baseball Spirits (プロ野球スピリッツ) is a series of realistic baseball simulation video games by Konami, licensed by Nippon Professional Baseball since the first title in 2004.
Professional Bowlers Association
Professional Bowlers Association (PBA), the main international body for professional ten-pin bowling; runs the PBA Tour, Regional Tour, and PBA50 Tour with members from over 30 countries; 2026 Tour titled by Go Bowling, airing on The CW and CBS.
Professional boxing
Professional boxing: paid prizefighting under state commissions, scored by three judges on the 10-point must system, with four rival sanctioning bodies (WBC, WBA, IBF, WBO) issuing separate titles and rankings, regulated in the US by the 1996 PBSA and 2000 Ali Act.
Professional Bull Riders
Professional Bull Riders (PBR), founded 1992 by 20 riders leaving the PRCA, is the leading stand-alone bull riding organization; rides score up to 100 points over 8 seconds, with a $1 million year-end champion bonus.
Professional certification
Professional certification: a voluntary, nongovernmental credential recognizing occupational competence via examination, time-limited and renewable. Distinct from government licensure; held by over 43 million Americans in 2018.
Professional Children's School
Professional Children's School (PCS), founded 1914 in Manhattan by Jane Harris Hall and Jean Greer Robinson, is an independent day school, grades 4-12, at 132 West 60th Street for young performers, athletes, and models, offering flexible college-prep academics, not arts training.
Professional Corporations
A professional corporation, also called a professional service corporation (PSC), is a corporation created under state law that lets licensed professionals practice through a company, usually marked PC.
Professional Darts Corporation
The Professional Darts Corporation (PDC) is the leading professional darts organization, formed in 1992 as the World Darts Council after a split from the British Darts Organisation. It runs a 128-player Tour Card circuit, rankings based on prize money, and the PDC World Darts Championship at Alexandra Palace.
Professional degree
Professional degree: a credential certifying readiness to begin licensed practice in a profession, such as the J.D. or M.D. In US federal student aid it determines higher loan limits ($200,000 vs $100,000), a definition contested in the 2026 RISE rule litigation.
Professional development
Teacher professional development (PD, in-service training, CPD) is structured learning for practicing teachers. Meta-analyses of 128 rigorous trials find an average effect of 0.09 on student achievement, with effectiveness depending on design mechanisms rather than format.
Professional Development League
Professional Development League (PDL), English U21 league for 20 Category Two academy clubs, one tier below Premier League 2; North/South regional groups, 28 fixtures, and from 2025/26 a cross-category knockout with PL2 clubs finishing 17th-24th.