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Persephin is a neurotrophic factor in the glial cell line-derived neurotrophic factor (GDNF) family. Persephin shares around a 40% similarity in amino acid sequence compared to GDNF and neurturin, two members of the GDNF family. [ 1 ]
Persephin has been found to be less potent than other members of the GDNF family . I... | https://en.wikipedia.org/wiki/Persephin |
The Perseus-Taurus Shell (also shortened to the Per-Tau shell ) is a near-spherical cavity in the interstellar medium, 500 light-years wide, located in the Perseus-Taurus constellations. [ 1 ] [ 2 ] A team from the Harvard Smithsonian Center for Astrophysics led by Catherine Zucker and Shmuel Bialy discovered the struc... | https://en.wikipedia.org/wiki/Perseus-Taurus_Shell |
The Perseus Digital Library , formerly known as the Perseus Project , is a free-access digital library founded by Gregory Crane in 1987 and hosted by the Department of Classical Studies of Tufts University . One of the pioneers of digital libraries, its self-proclaimed mission is to make the full record of humanity ava... | https://en.wikipedia.org/wiki/Perseus_Digital_Library |
In topological data analysis , a persistence barcode , sometimes shortened to barcode , is an algebraic invariant associated with a filtered chain complex or a persistence module that characterizes the stability of topological features throughout a growing family of spaces . [ 1 ] Formally, a persistence barcode consis... | https://en.wikipedia.org/wiki/Persistence_barcode |
The persistence length is a basic mechanical property quantifying the bending stiffness of a polymer .
The molecule behaves like a flexible elastic rod/beam ( beam theory ). Informally, for pieces of the polymer that are shorter than the persistence length, the molecule behaves like a rigid rod, while for pieces of the... | https://en.wikipedia.org/wiki/Persistence_length |
In mathematics , the persistence of a number is the number of times one must apply a given operation to an integer before reaching a fixed point at which the operation no longer alters the number.
Usually, this involves additive or multiplicative persistence of a non-negative integer, which is how often one has to rep... | https://en.wikipedia.org/wiki/Persistence_of_a_number |
Persistent, bioaccumulative and toxic substances ( PBTs ) are a class of compounds that have high resistance to degradation from abiotic and biotic factors, high mobility in the environment and high toxicity. Because of these factors PBTs have been observed to have a high order of bioaccumulation and biomagnification ... | https://en.wikipedia.org/wiki/Persistent,_bioaccumulative_and_toxic_substances |
A persistent carbene (also known as stable carbene ) is an organic molecule whose natural resonance structure has a carbon atom with incomplete octet (a carbene ), but does not exhibit the tremendous instability typically associated with such moieties. The best-known examples and by far largest subgroup are the N -het... | https://en.wikipedia.org/wiki/Persistent_carbene |
In physics , persistent current is a perpetual electric current that does not require an external power source. Such a current is impossible in normal electrical devices, since all commonly-used conductors have a non-zero resistance, and this resistance would rapidly dissipate any such current as heat. However, in supe... | https://en.wikipedia.org/wiki/Persistent_current |
Commonly referred to as phosphorescence , persistent luminescence is the emission of light by a phosphorescent material after an excitation by ultraviolet or visible light .
The mechanism underlying this phenomenon is not fully understood. [ 1 ] It is neither fluorescence nor phosphorescence . [ 2 ] [ 3 ] In fluoresce... | https://en.wikipedia.org/wiki/Persistent_luminescence |
The persistent radical effect (PRE) in chemistry describes and explains the selective product formation found in certain free-radical cross-reactions. In these type of reactions, different radicals compete in secondary reactions. The so-called persistent (long-lived) radicals do not self-terminate and only react in cr... | https://en.wikipedia.org/wiki/Persistent_radical_effect |
Persister cells are subpopulations of cells that resist treatment, and become antimicrobial tolerant by changing to a state of dormancy or quiescence. [ 1 ] [ 2 ] Persister cells in their dormancy do not divide. [ 3 ] The tolerance shown in persister cells differs from antimicrobial resistance in that the tolerance is... | https://en.wikipedia.org/wiki/Persister_cells |
A personal communications service ( PCS ) is set of communications capabilities that provide a combination of terminal mobility, personal mobility , and service profile management. [ 1 ] This class of services comprises several types of wireless voice or wireless data communications systems, typically incorporating dig... | https://en.wikipedia.org/wiki/Personal_Communications_Service |
The Personal Genome Project (PGP) is a long term, large cohort study which aims to sequence and publicize the complete genomes and medical records of 100,000 volunteers, in order to enable research into personal genomics and personalized medicine . It was initiated by Harvard University 's George M. Church in 2005. [ 1... | https://en.wikipedia.org/wiki/Personal_Genome_Project |
In telecommunication , a personal communications service is defined by the Alliance for Telecommunications Industry Solutions (ATIS) as "a set of capabilities that allows some combination of personal mobility, terminal mobility, and service profile management". [ 1 ]
Personal communications services use a special non-... | https://en.wikipedia.org/wiki/Personal_communications_service_(NANP) |
Personal environmental impact accounting (PEIA) is a computer software-based methodology developed in 1992 by Don Lotter [ 1 ] [ 2 ] [ 3 ] for quantifying an individual's impact on the environment via analysis of answers to an extensive quantity-based questionnaire that the individual fills out regarding their lifestyl... | https://en.wikipedia.org/wiki/Personal_environmental_impact_accounting |
The term personal equation , in 19th- and early 20th-century science , referred to the idea that different observers have different reaction times, which can introduce bias when it comes to measurements and observations . [ 1 ]
The term originated in astronomy , when it was discovered that numerous observers making s... | https://en.wikipedia.org/wiki/Personal_equation |
Personal knowledge management ( PKM ) is a process of collecting information that a person uses to gather, classify, store, search, retrieve and share knowledge in their daily activities ( Grundspenkis 2007 ) and the way in which these processes support work activities ( Wright 2005 ). It is a response to the idea that... | https://en.wikipedia.org/wiki/Personal_knowledge_management |
Personal media are media of communication which are used by an individual rather than by a corporation or institution . [ 1 ] They are generally contrasted with mass media which are produced by teams of people and broadcast to a general population. [ 2 ] : 1–7 In other words, personal media allow individuals, as oppose... | https://en.wikipedia.org/wiki/Personal_media |
A Personal Navigation Assistant ( PNA ) also known as Personal Navigation Device or Portable Navigation Device ( PND ) is a portable electronic product which combines a positioning capability (such as GPS ) and navigation functions.
Some PNA devices are PDAs with limited features and can be unlocked. [ 1 ]
The earlie... | https://en.wikipedia.org/wiki/Personal_navigation_assistant |
Personality neuroscience uses neuroscientific methods to study the neurobiological mechanisms underlying individual differences in stable psychological attributes. Specifically, personality neuroscience aims to investigate the relationships between inter-individual variation in brain structures as well as functions and... | https://en.wikipedia.org/wiki/Personality_neuroscience |
A personalization management system ( PMS ) is an integrated software solution that enables users in an organization to manage and deliver personalized messages, campaigns, and interactive experiences to consumers across different communications channels and devices.
The term PMS was first used in a 2003 study [ 1 ] o... | https://en.wikipedia.org/wiki/Personalization_management_system |
Personalized medicine , also referred to as precision medicine , is a medical model that separates people into different groups —with medical decisions , practices , interventions and/or products being tailored to the individual patient based on their predicted response or risk of disease .The terms personalized medici... | https://en.wikipedia.org/wiki/Personalized_medicine |
Personoid is the concept coined by Stanisław Lem , a Polish science-fiction writer, in Non Serviam, from his book A Perfect Vacuum (1971). His personoids are an abstraction of functions of human mind and they live in computers; they do not need any human-like physical body.
In cognitive and software modeling, personoi... | https://en.wikipedia.org/wiki/Personoid |
A Persoz pendulum is a device used for measuring hardness of materials . The instrument consists of a pendulum which is free to swing on two balls resting on a coated test panel. The pendulum hardness test is based on the principle that the amplitude of the pendulum's oscillation will decrease more quickly when support... | https://en.wikipedia.org/wiki/Persoz_pendulum |
Geological perspective correlation is a theory in geology describing geometrical regularities in the layering of sediments. Seventy percent of the Earth's surface are occupied by sedimentary basins [ 1 ] – volumes consisted of sediments accumulated during million years, and alternated by long interruptions in sedimenta... | https://en.wikipedia.org/wiki/Perspective_geological_correlation |
Perspiration , also known as sweat , is the fluid secreted by sweat glands in the skin of mammals . [ 1 ]
Two types of sweat glands can be found in humans: eccrine glands and apocrine glands . [ 2 ] The eccrine sweat glands are distributed over much of the body and are responsible for secreting the watery, brackish sw... | https://en.wikipedia.org/wiki/Perspiration |
Perstraction is a membrane extraction process, where two liquid phases are contacted across a membrane. The desired species in the feed (solute), selectively crosses the membrane into the extracting solution. Perstraction was originally developed to overcome the downsides of liquid–liquid extraction , for example extra... | https://en.wikipedia.org/wiki/Perstraction |
In chemistry , persulfide refers to the functional group R-S-S-H. [ 1 ] Persulfides are intermediates in the biosynthesis of iron-sulfur proteins [ 2 ] and are invoked as precursors to hydrogen sulfide , a signaling molecule.
The nomenclature used for organosulfur compounds is often non-systematic. Sometimes persulfi... | https://en.wikipedia.org/wiki/Persulfide |
Perturb-seq (also known as CRISP-seq and CROP-seq ) refers to a high-throughput method of performing single cell RNA sequencing (scRNA-seq) on pooled genetic perturbation screens. [ 1 ] [ 2 ] [ 3 ] Perturb-seq combines multiplexed CRISPR mediated gene inactivations with single cell RNA sequencing to assess comprehensiv... | https://en.wikipedia.org/wiki/Perturb-seq |
In astronomy , perturbation is the complex motion of a massive body subjected to forces other than the gravitational attraction of a single other massive body . [ 1 ] The other forces can include a third (fourth, fifth, etc.) body, resistance , as from an atmosphere , and the off-center attraction of an oblate or other... | https://en.wikipedia.org/wiki/Perturbation_(astronomy) |
The perturbed γ-γ angular correlation , PAC for short or PAC-Spectroscopy , is a method of nuclear solid-state physics with which magnetic and electric fields in crystal structures can be measured. In doing so, electrical field gradients and the Larmor frequency in magnetic fields as well as dynamic effects are determi... | https://en.wikipedia.org/wiki/Perturbed_angular_correlation |
Pertussis toxin ( PT ) is a protein-based AB 5 -type exotoxin produced by the bacterium Bordetella pertussis , [ 2 ] which causes whooping cough . PT is involved in the colonization of the respiratory tract and the establishment of infection. [ 3 ] Research suggests PT may have a therapeutic role in treating a number o... | https://en.wikipedia.org/wiki/Pertussis_toxin |
Pervaded volume is a measure of the size of a polymer chain in space. In particular, it is "the volume of solution spanned by the polymer chain". [ 1 ]
The pervaded volume V scales as the cube of the chain size
V ≈ R 3 {\displaystyle V\approx R^{3}}
R is some length scale describing the chain conformation such as t... | https://en.wikipedia.org/wiki/Pervaded_volume |
Pervaporation (or pervaporative separation) is a processing method for the separation of mixtures of liquids by partial vaporization through a non-porous or porous membrane . [ 1 ]
The term pervaporation is a portmanteau of the two steps of the process: (a) permeation through the membrane by the permeate, then (b) its... | https://en.wikipedia.org/wiki/Pervaporation |
Pervasive informatics is the study of how information affects interactions with the built environments they occupy. The term and concept were initially introduced by Professor Kecheng Liu during a keynote speech at the SOLI 2008 international conference. [ 1 ] [ failed verification ]
The built environment is rich with... | https://en.wikipedia.org/wiki/Pervasive_informatics |
Pervious concrete (also called porous concrete , permeable concrete , no fines concrete and porous pavement ) is a special type of concrete with a high porosity used for concrete flatwork applications that allows water from precipitation and other sources to pass directly through, thereby reducing the runoff from a sit... | https://en.wikipedia.org/wiki/Pervious_concrete |
In chemistry , perxenates are salts of the yellow [ 1 ] xenon -containing anion XeO 4− 6 . [ 2 ] This anion has octahedral molecular geometry , as determined by Raman spectroscopy , having O–Xe–O bond angles varying between 87° and 93°. [ 3 ] The Xe–O bond length was determined by X-ray crystallography to be 1.875 Å. [... | https://en.wikipedia.org/wiki/Perxenate |
In radio astronomy , perytons are short man-made radio signals of a few milliseconds resembling fast radio bursts (FRB). A peryton differs from radio frequency interference by the fact that it is a pulse of several to tens of millisecond duration which sweeps down in frequency. They are further verified by the fact tha... | https://en.wikipedia.org/wiki/Peryton_(astronomy) |
In the philosophy of science , the pessimistic induction , also known as the pessimistic meta-induction , is an argument which seeks to rebut scientific realism , particularly the scientific realist's notion of epistemic optimism. The pessimistic meta-induction is the argument that if past successful and accepted scien... | https://en.wikipedia.org/wiki/Pessimistic_induction |
Pestalotiopsis microspora is a species of endophytic fungus capable of breaking down and digesting polyurethane . [ 1 ] Originally identified in 1880 in fallen foliage of common ivy ( Hedera helix ) in Buenos Aires , [ 2 ] it also causes leaf spot in Hypericum 'Hidcote' ( Hypericum patulum ) shrubs in Japan . [ 3 ]
H... | https://en.wikipedia.org/wiki/Pestalotiopsis_microspora |
Pesticides are substances that are used to control pests . [ 1 ] They include herbicides , insecticides , nematicides , fungicides , and many others (see table). [ 2 ] The most common of these are herbicides, which account for approximately 50% of all pesticide use globally. [ 3 ] Most pesticides are used as plant prot... | https://en.wikipedia.org/wiki/Pesticide |
Pesticide application is the practical way in which pesticides (including herbicides , fungicides , insecticides , or nematode control agents) are delivered to their biological targets ( e.g. pest organism, crop or other plant). Public concern about the use of pesticides has highlighted the need to make this process as... | https://en.wikipedia.org/wiki/Pesticide_application |
A Pesticide detection kit is a kit that scientific test kit detects the presence of pesticide residues . Various organizations create them, among them Defence Food Research Laboratory of India . [ 1 ]
This biochemistry article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Pesticide_detection_kit |
Pesticide drift , also known as spray drift , is the unintentional diffusion of pesticides toward nontarget species. It is one of the most negative effects of pesticide application . Drift can damage human health, environment, and crops. [ 1 ] [ 2 ] Together with runoff and leaching, drift is a mechanism for agricultu... | https://en.wikipedia.org/wiki/Pesticide_drift |
A pesticide poisoning occurs when pesticides , chemicals intended to control a pest , affect non-target organisms such as humans, wildlife, plants, or bees . There are three types of pesticide poisoning. The first of the three is a single and short-term very high level of exposure which can be experienced by individual... | https://en.wikipedia.org/wiki/Pesticide_poisoning |
Pesticide residue refers to the pesticides that may remain on or in food, after they are applied to food crops . [ 1 ] The maximum allowable levels of these residues in foods are stipulated by regulatory bodies in many countries. Regulations such as pre-harvest intervals also prevent harvest of crop or livestock produc... | https://en.wikipedia.org/wiki/Pesticide_residue |
Pesticide resistance describes the decreased susceptibility of a pest population to a pesticide that was previously effective at controlling the pest. Pest species evolve pesticide resistance via natural selection : the most resistant specimens survive and pass on their acquired heritable changes traits to their offspr... | https://en.wikipedia.org/wiki/Pesticide_resistance |
The byte is a unit of digital information that most commonly consists of eight bits . Historically, the byte was the number of bits used to encode a single character of text in a computer [ 1 ] [ 2 ] and for this reason it is the smallest addressable unit of memory in many computer architectures . To disambiguate arbit... | https://en.wikipedia.org/wiki/Petabyte |
Petascale computing refers to computing systems capable of performing at least 1 quadrillion (10^15) floating-point operations per second (FLOPS) . These systems are often called petaflops systems and represent a significant leap from traditional supercomputers in terms of raw performance, enabling them to handle vast ... | https://en.wikipedia.org/wiki/Petascale_computing |
The Petasis reaction (alternatively called the Petasis borono–Mannich (PBM) reaction ) is the multi-component reaction of an amine , a carbonyl , and a vinyl - or aryl - boronic acid to form substituted amines.
Reported in 1993 by Nicos Petasis as a practical method towards the synthesis of a geometrically pure antifu... | https://en.wikipedia.org/wiki/Petasis_reaction |
The Petasis reagent , named after Nicos A. Petasis, is an organotitanium compound with the formula Cp 2 Ti(CH 3 ) 2 . [ 1 ] It is an orange-colored solid.
The Petasis reagent is prepared by the salt metathesis reaction of methylmagnesium chloride or methyllithium [ 2 ] with titanocene dichloride : [ 3 ]
This compound... | https://en.wikipedia.org/wiki/Petasis_reagent |
Peter Jephson Cameron FRSE (born 23 January 1947) is an Australian mathematician who works in group theory , combinatorics , coding theory , and model theory . He is currently Emeritus Professor at the University of St Andrews [ 2 ] and Queen Mary University of London .
Cameron received a B.Sc. from the University of ... | https://en.wikipedia.org/wiki/Peter_Cameron_(mathematician) |
The Peter Debye Award in Physical Chemistry is awarded annually by the American Chemical Society "to encourage and reward outstanding research in physical chemistry ". [ 1 ] The award is named after Peter Debye and
granted without regard to age or nationality. | https://en.wikipedia.org/wiki/Peter_Debye_Award |
Péter Gács (Hungarian pronunciation: ['pe:ter 'ga:tʃ]; born May 9, 1947), professionally also known as Peter Gacs , is a Hungarian - American mathematician and computer scientist, professor, and an external member of the Hungarian Academy of Sciences. He is well known for his work in reliable computation, randomness i... | https://en.wikipedia.org/wiki/Peter_Gacs |
Peter Malcolm Wallace Gill (born 9 November 1962) [ 1 ] is a New Zealand theoretical and computational chemist known for his contribution to density functional theory (DFT). He is an early and main contributor to the computational chemistry software Q-Chem and was the president of the company during 1998–2013. He is es... | https://en.wikipedia.org/wiki/Peter_Gill_(chemist) |
Peter H. Gleick ( / ɡ l ɪ k / ; born 1956) is an American scientist working on issues related to the environment . [ 1 ] He works at the Pacific Institute in Oakland, California , which he co-founded in 1987. In 2003 he was awarded a MacArthur Fellowship for his work on water resources. Among the issues he has addresse... | https://en.wikipedia.org/wiki/Peter_Gleick |
Peter Hannaford AC (born 15 July 1939) is an Australian academic and university professor. [ 1 ] He is the Director of the Centre for Atom Optics and Ultrafast Spectroscopy at Swinburne University of Technology in Melbourne , and winner of the Walter Boas Medal in 1985. [ 2 ]
Hannaford studied at the University of Mel... | https://en.wikipedia.org/wiki/Peter_Hannaford |
Peter J. H. Scott FRSC CChem (born July 27, 1979) is a British and American chemist and radiochemist who is the Paul L. Carson Collegiate Professor of Radiology at the University of Michigan in the United States. He is also a professor of radiology, professor of pharmacology and professor of medicinal chemistry, and a ... | https://en.wikipedia.org/wiki/Peter_J._H._Scott |
Peter Koch (October 15, 1920 – February 14, 1998) was an American engineer and wood scientist who was considered an expert in the field of wood technology by his peers. [ 1 ] From 1963 to 1982, Koch led a team of US Forest Service scientists in forest products utilization research specific to forests of the southeaster... | https://en.wikipedia.org/wiki/Peter_Koch_(wood_scientist) |
Peter Koellner is professor of philosophy at Harvard University . He received his Ph.D. from MIT in 2003. His main areas of research are mathematical logic , specifically set theory , and philosophy of mathematics , philosophy of physics , analytic philosophy , and philosophy of language . [ 1 ]
In 2008 Koellner was a... | https://en.wikipedia.org/wiki/Peter_Koellner |
Peter Manfred Gruber (28 August 1941, Klagenfurt – 7 March 2017, Vienna ) was an Austrian mathematician working in geometric number theory [ 1 ] as well as in convex and discrete geometry. [ 2 ] [ 3 ]
Gruber obtained his PhD at the University of Vienna in 1966, under the supervision of Nikolaus Hofreiter . [ 4 ] From ... | https://en.wikipedia.org/wiki/Peter_M._Gruber |
Sir Peter Mansfield FRS [ 1 ] [ 2 ] (9 October 1933 – 8 February 2017) [ 3 ] was an English physicist who was awarded the 2003 Nobel Prize in Physiology or Medicine , shared with Paul Lauterbur , for discoveries concerning Magnetic Resonance Imaging (MRI). Mansfield was a professor at the University of Nottingham . [ 4... | https://en.wikipedia.org/wiki/Peter_Mansfield |
Peter Nemes is a Hungarian-American chemist, who is active in the fields of bioanalytical chemistry, mass spectrometry , cell/developmental biology, neuroscience, and biochemistry .
Nemes has been an associate professor at the University of Maryland, College Park (UMD) since January 2018. Prior to his appointment the... | https://en.wikipedia.org/wiki/Peter_Nemes |
Peter P. Chen Award is an annually presented award to honor one individual for their contributions to the field of conceptual modeling . Named after the computer scientist Peter Chen , the award was started in 2008 by the publisher Elsevier as a means of celebrating the 25th anniversary of the journal Data & Knowledge ... | https://en.wikipedia.org/wiki/Peter_P._Chen_Award |
Peter Howard Rheinstein (born September 7, 1943) is an American physician , lawyer , author , and administrator (both private and governmental). He was an official of the Food and Drug Administration (FDA) from 1974 to 1999.
Rheinstein, a General Motors Scholar, received a B.A. with high honors from Michigan State Un... | https://en.wikipedia.org/wiki/Peter_Rheinstein |
Peter Rona , born as Peter Rosenfeld (* 13. May 1871 in Budapest ; † February or March 1945) was a Hungarian German Jewish physician and physiologist . [ 1 ]
This article about a biochemist is a stub . You can help Wikipedia by expanding it .
This article about a German scientist is a stub . You can help Wikipedia by... | https://en.wikipedia.org/wiki/Peter_Rona_(physician) |
Peter Michael Rosenthal (June 1, 1941 – May 25, 2024) was an American-Canadian mathematician, lawyer, and activist who was Professor of Mathematics at the University of Toronto , [ 5 ] and an adjunct professor of Law at the University of Toronto Law School . [ 6 ] [ 7 ]
Rosenthal grew up in a Jewish family in Flushing... | https://en.wikipedia.org/wiki/Peter_Rosenthal |
Peter Richard Schreiner (born 17 November 1965 in Nuremberg , Germany) is a German chemist who is a professor at Justus Liebig University Giessen . As of 2022 [update] , his h-index is 73. [ 1 ]
Schreiner studied at the University of Erlangen-Nuremberg , where he received his diploma in 1992 (with Paul von Ragué Schle... | https://en.wikipedia.org/wiki/Peter_Schreiner_(chemist) |
Peter Schwerdtfeger (born 1 September 1955) is a German scientist. He holds a chair in theoretical chemistry at Massey University in Auckland , New Zealand, serves as director of the Centre for Theoretical Chemistry and Physics, is the head of the New Zealand Institute for Advanced Study, and is a former president of t... | https://en.wikipedia.org/wiki/Peter_Schwerdtfeger |
Peter Trefonas (born 1958) is a retired DuPont Fellow (a senior scientist) at DuPont , where he had worked on the development of electronic materials . He is known for innovations in the chemistry of photolithography , particularly the development of anti-reflective coatings and polymer photoresists that are used to cr... | https://en.wikipedia.org/wiki/Peter_Trefonas |
Peter W. Heller (born 5 September 1957) is a former deputy mayor of the City of Freiburg im Breisgau in Germany, economist, investor and venture philanthropist.
Peter W. Heller was born in Frankfurt am Main , the son of Wolfgang Heller, entrepreneur in the printing industry, and Ingeborg Heller. He studied economics a... | https://en.wikipedia.org/wiki/Peter_W._Heller |
Peters four-step chemistry is a systematically reduced mechanism for methane combustion , named after Norbert Peters , who derived it in 1985. [ 1 ] [ 2 ] [ 3 ] The mechanism reads as [ 4 ]
The mechanism predicted four different regimes where each reaction takes place. The third reaction, known as radical consumption ... | https://en.wikipedia.org/wiki/Peters_four-step_chemistry |
In mathematics, the Peters polynomials s n ( x ) are polynomials studied by Peters ( 1956 , 1956b ) given by the generating function
( Roman 1984 , 4.4.6), ( Boas & Buck 1958 , p.37). They are a generalization of the Boole polynomials .
This polynomial -related article is a stub . You can help Wikipedia by expanding ... | https://en.wikipedia.org/wiki/Peters_polynomials |
The Petersen matrix is a comprehensive description of systems of biochemical reactions used to model reactors for pollution control (engineered decomposition ) as well as in environmental systems . It has as many columns as the number of relevant involved components ( chemicals , pollutants , biomasses , gases ) and as... | https://en.wikipedia.org/wiki/Petersen_matrix |
In geometry , the Petersen–Morley theorem states that, if a , b , c are three general skew lines in space, if a ′ , b ′ , c ′ are the lines of shortest distance
respectively for the pairs (b,c) , (c,a) and (a,b) ,
and if p , q and r are the lines of shortest distance respectively
for the pairs (a,a ′ ) , (b,b ′ ) and (... | https://en.wikipedia.org/wiki/Petersen–Morley_theorem |
The Peterson olefination (also called the Peterson reaction ) is the chemical reaction of α-silyl carbanions ( 1 in diagram below) with ketones (or aldehydes ) to form a β-hydroxysilane ( 2 ) which eliminates to form alkenes ( 3 ). [ 1 ]
Several reviews have been published. [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ]
One attractiv... | https://en.wikipedia.org/wiki/Peterson_olefination |
The reflected binary code ( RBC ), also known as reflected binary ( RB ) or Gray code after Frank Gray , is an ordering of the binary numeral system such that two successive values differ in only one bit (binary digit).
For example, the representation of the decimal value "1" in binary would normally be " 001 ", and "... | https://en.wikipedia.org/wiki/Petherick_code |
petite (ρ–) is a mutant first discovered in the yeast Saccharomyces cerevisiae . Due to the defect in the respiratory chain, 'petite' yeast are unable to grow on media containing only non-fermentable carbon sources (such as glycerol or ethanol) and form small colonies when grown in the presence of fermentable carbon so... | https://en.wikipedia.org/wiki/Petite_mutation |
The Petkau effect is an early counterexample to linear-effect assumptions usually made about radiation exposure. It was found by Dr. Abram Petkau at the Atomic Energy of Canada Whiteshell Nuclear Research Establishment , Manitoba and published in Health Physics March 1972. [ 1 ] The Petkau effect was coined by Swiss nu... | https://en.wikipedia.org/wiki/Petkau_effect |
Petko Stoyanov Dimitrov ( Bulgarian : Петко Стоянов Димитров ) (16 September 1944 – 29 April 2023) was a Bulgarian marine geologist and oceanographer from the Institute of Oceanology - Bulgarian Academy of Sciences in Varna . He has been an early proponent of the Black Sea deluge hypothesis which gained public notoriet... | https://en.wikipedia.org/wiki/Petko_Dimitrov |
Petkovšek's algorithm (also Hyper ) is a computer algebra algorithm that computes a basis of hypergeometric terms solution of its input linear recurrence equation with polynomial coefficients . Equivalently, it computes a first order right factor of linear difference operators with polynomial coefficients. This algorit... | https://en.wikipedia.org/wiki/Petkovšek's_algorithm |
The Petrenko-Kritschenko reaction is a classic multicomponent- name reaction [ 1 ] that is closely related to the Robinson–Schöpf tropinone synthesis, but was published 12 years earlier.
In the original publication [ 2 ] diethyl-α-ketoglurate, a derivative of acetonedicarboxylic acid , is used in combination with ammo... | https://en.wikipedia.org/wiki/Petrenko-Kritschenko_piperidone_synthesis |
Petri AG was an automotive parts company based in Germany . It was acquired by the Japanese company Takata Corporation in 2000, forming the European subsidiary Takata-Petri. In 2018, operations became part of the new Joyson Safety Systems as Joyson Safety Systems Aschaffenburg GmbH , after the 2017 bankruptcy of Takata... | https://en.wikipedia.org/wiki/Petri_AG |
A Petri dish (alternatively known as a Petri plate or cell-culture dish ) is a shallow transparent lidded dish that biologists use to hold growth medium in which cells can be cultured , [ 1 ] [ 2 ] originally, cells of bacteria , fungi and small mosses . [ 3 ] The container is named after its inventor, German bacteriol... | https://en.wikipedia.org/wiki/Petri_dish |
The Petrie Prize Lecture is an award given in alternate years by the Canadian Astronomical Society to an outstanding astrophysicist . The award commemorates the contributions to astrophysical research of the Canadian astronomer Robert M. Petrie . [ 1 ]
Source: Canadian Astronomical Society | https://en.wikipedia.org/wiki/Petrie_Prize_Lecture |
In geology , petrifaction or petrification (from Ancient Greek πέτρα ( pétra ) ' rock, stone ' ) is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals . Petrified wood typifies this process, but all organisms,... | https://en.wikipedia.org/wiki/Petrifaction |
The Neogen Petrifilm plate is an all-in-one plating system made by the Food Safety Division of the Neogen Corporation . They are heavily used in many microbiology -related industries and fields to culture various micro-organisms and are meant to be a more efficient method for detection and enumeration compared to conv... | https://en.wikipedia.org/wiki/Petrifilm |
Petrobactin is a bis- catechol siderophore found in M. hydrocarbonoclasticus , A. macleodii , and the anthrax -producing B. anthracis . [ 2 ] Like other siderophores petrobactin is a highly specific iron(III) transport ligand, contributing to the marine microbial uptake of environmental iron . [ 2 ] [ 3 ]
The iron- ch... | https://en.wikipedia.org/wiki/Petrobactin |
The Petrochemical Heritage Award was established in 1997, "to recognize individuals who made outstanding contributions to the petrochemical community ." [ 1 ] The award is intended to inspire achievement and to promote public understanding. The award winner is chosen annually by the Founders Club and the Science Histor... | https://en.wikipedia.org/wiki/Petrochemical_Heritage_Award |
The petrochemical industry is concerned with the production and trade of petrochemicals . [ according to whom? ] A major part is constituted by the plastics (polymer) industry . [ according to whom? ] It directly interfaces with the petroleum industry , especially the downstream sector. [ according to whom? ]
The top ... | https://en.wikipedia.org/wiki/Petrochemical_industry |
The emergence of oil production in the territory now known as Romania dates back to 1857, [ 1 ] with oil facilities gaining strategic military significance in 1916 during World War I . Throughout World War II , the Kingdom of Romania held the position as the largest oil producer in Europe, second only to the USSR, whos... | https://en.wikipedia.org/wiki/Petrochemical_industry_in_Romania |
Petrol piracy also sometimes called oil piracy or petro-piracy , is an act of piracy that specifically involves petroleum resources , or their transportation, consumption, and regulation. It should not be confused with the term oil war , as although both involve petroleum , petrol piracy always involves at least one of... | https://en.wikipedia.org/wiki/Petrol_piracy |
Petroleomics is the identification of the totality of the constituents of naturally occurring petroleum and crude oil using high resolution mass spectrometry . [ 1 ] [ 2 ] [ 3 ] In addition to mass determination, petroleomic analysis sorts the chemical compounds into heteroatom class ( nitrogen , oxygen and sulfur ), t... | https://en.wikipedia.org/wiki/Petroleomics |
Petroleum , also known as crude oil or simply oil , is a naturally occurring, yellowish-black liquid chemical mixture found in geological formations , consisting mainly of hydrocarbons . [ 1 ] The term petroleum refers both to naturally occurring unprocessed crude oil, as well as to petroleum products that consist of r... | https://en.wikipedia.org/wiki/Petroleum |
Petroleum Remediation Product (PRP) is a registered trade name of United Remediation Technology for a line of biodegradable wax-based hydrocarbon adsorbents and bioremediation agents. PRP was created in the 1990s by NASA ’s Jet Propulsion Laboratory and has been used to assist in remediating oil spills such as the 2010... | https://en.wikipedia.org/wiki/Petroleum_Remediation_Product |
Petroleum benzine is a hydrocarbon -based solvent mixture that is classified by its physical properties (e.g. boiling point, vapor pressure) rather than a specific chemical composition.
The chemical composition of a petroleum distillate can be modified to result in a solvent with a reduced concentration of unsaturated... | https://en.wikipedia.org/wiki/Petroleum_benzine |
Petroleum coke , abbreviated coke , pet coke or petcoke , is a final carbon -rich solid material that derives from oil refining , and is one type of the group of fuels referred to as cokes . Petcoke is the coke that, in particular, derives from a final cracking process—a thermo-based chemical engineering process that s... | https://en.wikipedia.org/wiki/Petroleum_coke |
Petroleum engineering is a field of engineering concerned with the activities related to the production of hydrocarbons , which can be either crude oil or natural gas . [ 1 ] Exploration and production are deemed to fall within the upstream sector of the oil and gas industry. Exploration , by earth scientists , and pet... | https://en.wikipedia.org/wiki/Petroleum_engineering |
Petroleum ether is the petroleum fraction consisting of aliphatic hydrocarbons and boiling in the range 35–60 °C, and commonly used as a laboratory solvent . [ 4 ] Despite the name, petroleum ether is not an ether ; the term is used only figuratively, signifying extreme lightness and volatility.
The very lightest, mos... | https://en.wikipedia.org/wiki/Petroleum_ether |
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