All articles starting with P
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Paramara dynasty
The Paramara dynasty, also called Parmar, was a medieval Indian royal house that ruled Malwa from Dhar, ending with the Delhi Sultanate's conquest in 1305.
Paramaribo
Paramaribo, capital of Suriname on the Suriname River, a former Dutch colonial town founded around Fort Zeelandia in 1667; its 2002 World Heritage historic inner city was placed on the List of World Heritage in Danger in 2026.
Paramasivan Fathima
Paramasivan Fathima (பரமசிவன் பாத்திமா) is a 2025 Tamil horror thriller written, directed, and produced by Esakki Karvannan, starring Vemal and Chaya Devi. Released 6 June 2025 with an A certificate, it depicts interfaith love and murders in rival Hindu and Christian villages, and received negative reviews.
Parambrata Chatterjee (পরমব্রত চট্টোপাধ্যায়)
Parambrata Chatterjee, also spelled Parambrata Chattopadhyay (পরমব্রত চট্টোপাধ্যায়), is an Indian actor and director, born in Kolkata in 1980, known for Bengali cinema and his Hindi debut in Kahaani (2012).
Paramecium
Paramecium, freshwater ciliate genus (P. tetraurelia, P. caudatum), 50-300 µm swimming cells with ~4,000 cilia, dual micronucleus/macronucleus system, and long-standing model organism for cilia, genome rearrangement, and genetics research.
Paramecium caudatum
Paramecium caudatum is a large freshwater ciliate, 170 to 310 micrometers long, first named in 1834 and a model organism for cell biology, genetics, and ecotoxicology.
Paramedian nasal cleft
Paramedian nasal cleft (Tessier number 1 cleft, alar cleft, isolated coloboma of the nose) is a rare congenital nasal coloboma beside the midline, ranging from a small notch with septal deviation to alar clefts, isolated or with cleft lip and hypertelorism.
Paramedic
Paramedic: highest US EMS licensure level (with EMR, EMT, AEMT), providing advanced out-of-hospital care; about 102,200 US jobs, $60,600 median wage, roots in 1960s Pittsburgh Freedom House.
Parameshvara
Parameshvara (परमेश्वर) was a Kerala astronomer and mathematician of the Nambutiri Brahmin community who founded the drigganita system of astronomical computation, completed in 1431, after decades of eclipse observations.
Paramesonephric duct
Paramesonephric (Müllerian) duct: paired embryonic ducts, first described by Johannes Peter Müller in 1830, that form the fallopian tubes, uterus, cervix, and upper third of the vagina, and regress in males under anti-Müllerian hormone.
Paramesotriton
Paramesotriton (Asian warty newts, 瘰螈属), a genus of Salamandridae newts from northern Vietnam and southern China; 14–17 species in two groups, originating near the late Oligocene in southwestern China.
Paramesu Biotech
Paramesu Biotech Limited is an Indian maize wet-milling company founded in 2011 and based in Devarapalli, Andhra Pradesh, producing starches, liquid glucose, and maltodextrin for food and industrial markets.
Paramesvaravarman I
Paramesvaravarman I (பரமேஸ்வரவர்மன்) was a Pallava king of Kanchipuram in South India who reigned from about 670 to about 695 CE and fought the Chalukya king Vikramaditya I.
Parameswara
Parameswara was a Sumatran prince from Palembang who founded Malacca around 1400 after fleeing through Singapore, became a Muslim as Sultan Iskandar Shah in 1414, and died in 1424.
Parameter
In statistics, a parameter is a fixed number describing a population or model, such as a population mean, whose unknown value must be estimated from samples.
Parameter (computer programming)
In computer programming, a parameter is a variable named in a function declaration that is initialized with a supplied value, called an argument, when the function is invoked.
Parameter server
A parameter server is a distributed machine learning architecture in which server nodes hold shared model parameters while worker nodes pull them and push back gradient updates.
Parameter space
A parameter space is the set of all values that the parameters of a statistical model may take; each point selects one probability distribution of the model.
Parameter-shift rule
The parameter-shift rule is a formula for computing the exact derivative of a quantum circuit's output by evaluating it at shifted parameter values, underpinning gradient-based training of variational quantum algorithms.
Parameterization and prior choice in MCMC
Parameterization and prior choice in MCMC are modeling decisions that leave the posterior unchanged but reshape the geometry a sampler must traverse, determining efficiency or convergence failure.
Parameterized complexity
Parameterized complexity is a branch of computational complexity theory that measures problem difficulty by input size plus a secondary parameter, developed by Rod Downey and Michael Fellows.
Parameterized post-Newtonian formalism
The parameterized post-Newtonian (PPN) formalism, or PPN formalism, compares metric theories of gravity in the weak-field, slow-motion limit through ten parameters, testing whether gravity follows general relativity or an alternative.
Paramethadione
Paramethadione (Paradione) is a discontinued oxazolidinedione anticonvulsant introduced by Abbott in 1949 for absence seizures, similar to but slightly less potent than trimethadione, acting via T-type calcium channel blockade in thalamic neurons.
Paramethasone acetate
Paramethasone acetate (Haldrone, Monocortin; CAS 1597-82-6) is a synthetic fluorinated glucocorticoid, the 21-acetate of paramethasone, about 10 times as potent as hydrocortisone with no mineralocorticoid activity; its US oral tablets are discontinued.
Parametric array
A parametric array is a transducer arrangement that converts two high-frequency ultrasound beams into a narrow, directional low-frequency beam, used in parametric sonar and audio spotlights.
Parametric bootstrap
The parametric bootstrap is a resampling method, introduced by Bradley Efron in 1979, that approximates a statistic's sampling distribution by simulating datasets from a fitted parametric model.
Parametric design
Parametric design is a design method in which design elements are related by explicit parameters, so changing one automatically regenerates dependent geometry; it underlies building information modeling and the architectural style Parametricism.
Parametric entangling gates
Parametric entangling gates are two-qubit quantum gates for superconducting circuits in which radio-frequency flux modulation of a tunable qubit or coupler activates fast, switchable entanglement.
Parametric equation
A parametric equation, also called a parametric representation, expresses a coordinate as an explicit function of parameters, describing curves like the circle x = r cos t, y = r sin t.
Parametric instability
A parametric instability is a wave-wave interaction in which a large-amplitude pump wave transfers energy to two daughter waves once the pump amplitude exceeds a threshold.