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The RFamide peptide family , or the RFamide-related peptides ( RFRPs ), are a family of neuropeptides . [ 1 ] [ 2 ] They are characterized by the possession of an Arg-Phe-NH 2 motif at their C-terminal extremities. [ 1 ] [ 2 ] Members of the family include: [ 1 ] [ 2 ] This biochemistry article is a stub . You can he...
https://en.wikipedia.org/wiki/RFamide_peptide_family
The arginine-glycine or arginine-glycine-glycine ( RG/RGG ) motif is a repeating amino acid sequence motif commonly found in RNA-binding proteins (RBPs). RGG regions in proteins are defined as two or more RG/RGG sequences within a stretch of 30 amino acids. [ 1 ] Initially named the RGG box , it confers a protein with ...
https://en.wikipedia.org/wiki/RG/RGG_motif
RG Jones Sound Engineering , or simply RG Jones , is a professional audiovisual , sound reinforcement and live touring production support company. Founded in 1926, RG Jones is the oldest British sound reinforcement company still in operation and one of the oldest in the world. [ 1 ] [ 2 ] Reginald Geoffrey Jones (1912...
https://en.wikipedia.org/wiki/RG_Jones_Sound_Engineering
The RH-32 was a radiation-hardened 32-bit MIPS R3000 based microprocessor chipset developed by the USAF Rome Laboratories [ 1 ] for the Ballistic Missile Defense Agency, and produced by Honeywell (later, TRW) for Aerospace applications. It achieves a throughput of 20 MIPS . It was a three-chip set, consisting of Centra...
https://en.wikipedia.org/wiki/RH-32
RIAA equalization is a specification for the recording and playback of phonograph records , established by the Recording Industry Association of America (RIAA). The purposes of the equalization are to permit greater recording times (by decreasing the mean width of each groove), to improve sound quality, and to reduce t...
https://en.wikipedia.org/wiki/RIAA_equalization
An ICE table or RICE box or RICE chart is a tabular system of keeping track of changing concentrations in an equilibrium reaction . ICE stands for initial, change, equilibrium . It is used in chemistry to keep track of the changes in amount of substance of the reactants and also organize a set of conditions that one wa...
https://en.wikipedia.org/wiki/RICE_chart
MDGRAPE-3 is an ultra-high performance petascale supercomputer system developed by the Riken research institute in Japan . It is a special purpose system built for molecular dynamics simulations, especially protein structure prediction . [ 1 ] MDGRAPE-3 consists of 201 units of 24 custom MDGRAPE-3 chips (4,824 total),...
https://en.wikipedia.org/wiki/RIKEN_MDGRAPE-3
The RIM-900 was one of the first wireless data devices, marketed as a two-way pager . It operated on the Mobitex network. It was a clam shell device that could fit on a belt. It had a small QWERTY keyboard for sending and receiving email and interactive messages. The product was introduced as Inter@ctive Paging in 19...
https://en.wikipedia.org/wiki/RIM-900
In the field of geodesy , Receiver Independent Exchange Format ( RINEX ) is a data interchange format for raw satellite navigation system data. This allows the user to post-process the received data to produce a more accurate result — usually with other data unknown to the original receiver, such as better models of th...
https://en.wikipedia.org/wiki/RINEX
The RISKS Digest or Forum On Risks to the Public in Computers and Related Systems is an online periodical published since 1985 by the Committee on Computers and Public Policy of the Association for Computing Machinery . The editor is Peter G. Neumann . It is a moderated forum concerned with the security and safety of ...
https://en.wikipedia.org/wiki/RISKS_Digest
RIVPACS (River Invertebrate Prediction and Classification System) is an aquatic biomonitoring system for assessing water quality in freshwater rivers in the United Kingdom . It is based on the macroinvertebrate species (such as freshwater shrimp , freshwater sponges , worms, crayfish , aquatic snails , freshwater musse...
https://en.wikipedia.org/wiki/RIVPACS
The RK2 Plasmid is a broad-host-range plasmid belonging to the incP incompatibility group [ 1 ] It is notable for its ability to replicate in a wide variety of single-celled organisms , which makes it suitable as a genetic engineering tool. [ 2 ] It is capable of transfer, replication, and maintenance in most genera of...
https://en.wikipedia.org/wiki/RK2_plasmid
RMG ( Real Space MultiGrid ) is an open source density functional theory electronic structure code distributed under the GNU General Public License . [ 1 ] [ 2 ] It solves Kohn-Sham equations directly on a 3D real space grid without using basis set functions. [ 2 ] RMG is highly scalable; it has been run on supercomput...
https://en.wikipedia.org/wiki/RMG_(program)
RNA-based evolution is a theory that posits that RNA is not merely an intermediate between Watson and Crick model of the DNA molecule and proteins , but rather a far more dynamic and independent role-player in determining phenotype . By regulating the transcription in DNA sequences, the stability of RNA, and the capabi...
https://en.wikipedia.org/wiki/RNA-based_evolution
RNA-binding proteins (often abbreviated as RBPs ) are proteins that bind to the double or single stranded RNA [ 1 ] in cells and participate in forming ribonucleoprotein complexes. RBPs contain various structural motifs , such as RNA recognition motif (RRM), dsRNA binding domain , zinc finger and others. [ 2 ] [ 3 ] Th...
https://en.wikipedia.org/wiki/RNA-binding_protein
RNA-dependent RNA polymerase ( RdRp ) or RNA replicase is an enzyme that catalyzes the replication of RNA from an RNA template. Specifically, it catalyzes synthesis of the RNA strand complementary to a given RNA template. This is in contrast to typical DNA-dependent RNA polymerases , which all organisms use to catalyze...
https://en.wikipedia.org/wiki/RNA-dependent_RNA_polymerase
RNA-induced transcriptional silencing ( RITS ) is a form of RNA interference by which short RNA molecules – such as small interfering RNA (siRNA) – trigger the downregulation of transcription of a particular gene or genomic region. This is usually accomplished by posttranslational modification of histone tails (e.g. me...
https://en.wikipedia.org/wiki/RNA-induced_transcriptional_silencing
RNA-targeting small molecules represent a class of small molecules , organic compounds with traditional drug properties (e.g., Lipinski's rule of five ) that can bind to RNA secondary or tertiary structures and alter translation patterns, localization, and degradation. Recent discoveries implicating RNA in the pathoge...
https://en.wikipedia.org/wiki/RNA-targeting_small_molecule_drugs
RNA Automation , a member of Rhein-Nadel Automation, was established in Birmingham UK, in 1986, and has progressed into becoming the major supplier of parts handling equipment in the UK . [ citation needed ] The company operates in the area of specialized Automation Engineering , providing automatic parts handling equi...
https://en.wikipedia.org/wiki/RNA_Automation
Graham A. Hudson The RNA Characterization of Secondary Structure Motifs database ( RNA CoSSMos ) is a repository of three-dimensional nucleic acid PDB structures containing secondary structure motifs ( loops, hairpin loops ...). [ 1 ] This Biological database -related article is a stub . You can help Wikipedia by ex...
https://en.wikipedia.org/wiki/RNA_CoSSMos
The RNA Tie Club was an informal scientific club, meant partly to be humorous, [ 1 ] of select scientists who were interested in how proteins were synthesised from genes, specifically the genetic code . [ 2 ] It was created by George Gamow upon a suggestion by James Watson in 1954 [ 2 ] when the relationship between nu...
https://en.wikipedia.org/wiki/RNA_Tie_Club
RNA activation (RNAa) is a small RNA-guided and Argonaute (Ago)-dependent gene regulation phenomenon in which promoter-targeted short double-stranded RNAs (dsRNAs) induce target gene expression at the transcriptional/epigenetic level. RNAa was first reported in a 2006 PNAS paper by Li et al . [ 1 ] who also coined the ...
https://en.wikipedia.org/wiki/RNA_activation
RNA editing (also RNA modification ) is a molecular process through which some cells can make discrete changes to specific nucleotide sequences within an RNA molecule after it has been generated by RNA polymerase . It occurs in all living organisms and is one of the most evolutionarily conserved properties of RNAs . [ ...
https://en.wikipedia.org/wiki/RNA_editing
RNA extraction is the purification of RNA from biological samples. This procedure is complicated by the ubiquitous presence of ribonuclease enzymes in cells and tissues, which can rapidly degrade RNA. [ 1 ] Several methods are used in molecular biology to isolate RNA from samples, the most common of these is guanidiniu...
https://en.wikipedia.org/wiki/RNA_extraction
RIP-chip (RNA immunoprecipitation chip) is a molecular biology technique which combines RNA immunoprecipitation with a microarray . The purpose of this technique is to identify which RNA sequences interact with a particular RNA binding protein of interest in vivo . [ 1 ] [ 2 ] [ 3 ] [ 4 ] It can also be used to determi...
https://en.wikipedia.org/wiki/RNA_immunoprecipitation_chip
The RNA integrity number (RIN) is an algorithm for assigning integrity values to RNA measurements. The integrity of RNA is a major concern for gene expression studies and traditionally has been evaluated using the 28S to 18S rRNA ratio, a method that has been shown to be inconsistent. [ 1 ] This inconsistency arises b...
https://en.wikipedia.org/wiki/RNA_integrity_number
RNA origami is the nanoscale folding of RNA , enabling the RNA to create particular shapes to organize these molecules. [ 1 ] It is a new method that was developed by researchers from Aarhus University and California Institute of Technology . [ 2 ] RNA origami is synthesized by enzymes that fold RNA into particular sha...
https://en.wikipedia.org/wiki/RNA_origami
In molecular biology , RNA polymerase (abbreviated RNAP or RNApol ), or more specifically DNA-directed/dependent RNA polymerase ( DdRP ), is an enzyme that catalyzes the chemical reactions that synthesize RNA from a DNA template. Using the enzyme helicase , RNAP locally opens the double-stranded DNA so that one strand...
https://en.wikipedia.org/wiki/RNA_polymerase
RNA polymerase 1 (also known as Pol I ) is, in higher eukaryotes , the polymerase that only transcribes ribosomal RNA (but not 5S rRNA , which is synthesized by RNA polymerase III ), a type of RNA that accounts for over 50% of the total RNA synthesized in a cell . [ 1 ] Pol I is a 590 kDa enzyme that consists of 14 pr...
https://en.wikipedia.org/wiki/RNA_polymerase_I
RNA polymerase II ( RNAP II and Pol II ) is a multiprotein complex that transcribes DNA into precursors of messenger RNA (mRNA) and most small nuclear RNA (snRNA) and microRNA . [ 1 ] [ 2 ] It is one of the three RNAP enzymes found in the nucleus of eukaryotic cells. [ 3 ] A 550 kDa complex of 12 subunits, RNAP II is t...
https://en.wikipedia.org/wiki/RNA_polymerase_II
In eukaryote cells, RNA polymerase III (also called Pol III ) is a protein that transcribes DNA to synthesize 5S ribosomal RNA , tRNA , and other small RNAs. The genes transcribed by RNA Pol III fall in the category of "housekeeping" genes whose expression is required in all cell types and most environmental condition...
https://en.wikipedia.org/wiki/RNA_polymerase_III
RNA polymerase II holoenzyme is a form of eukaryotic RNA polymerase II that is recruited to the promoters of protein -coding genes in living cells. [ 1 ] [ 2 ] It consists of RNA polymerase II , a subset of general transcription factors , and regulatory proteins known as SRB proteins [ clarification needed ] . RNA pol...
https://en.wikipedia.org/wiki/RNA_polymerase_II_holoenzyme
RNA silencing or RNA interference refers to a family of gene silencing effects by which gene expression is negatively regulated by non-coding RNAs such as microRNAs . RNA silencing may also be defined as sequence-specific regulation of gene expression triggered by double-stranded RNA ( dsRNA ). [ 1 ] RNA silencing mech...
https://en.wikipedia.org/wiki/RNA_silencing
An RNA spike-in is an RNA transcript of known sequence and quantity used to calibrate measurements in RNA hybridization assays , such as DNA microarray experiments , RT-qPCR , and RNA-Seq . [ 1 ] A spike-in is designed to bind to a DNA molecule with a matching sequence , known as a control probe . [ 2 ] [ 3 ] [ 4 ] Th...
https://en.wikipedia.org/wiki/RNA_spike-in
RNA splicing is a process in molecular biology where a newly-made precursor messenger RNA (pre- mRNA ) transcript is transformed into a mature messenger RNA ( mRNA ). It works by removing all the introns (non-coding regions of RNA) and splicing back together exons (coding regions). For nuclear-encoded genes , splicing ...
https://en.wikipedia.org/wiki/RNA_splicing
RNA therapeutics are a new class of medications based on ribonucleic acid (RNA) . Research has been working on clinical use since the 1990s, with significant success in cancer therapy in the early 2010s. [ 1 ] In 2020 and 2021, mRNA vaccines have been developed globally for use in combating the coronavirus disease (COV...
https://en.wikipedia.org/wiki/RNA_therapeutics
An RNA timestamp is a technology that enables the age of any given RNA transcript to be inferred by exploiting RNA editing . [ 1 ] In this technique, the RNA of interest is tagged to an adenosine rich reporter motif that consists of multiple MS2 binding sites. These MS2 binding sites recruit a complex composed of ADAR2...
https://en.wikipedia.org/wiki/RNA_timestamp
RNA velocity is based on bridging measurements to an underlying mechanism, mRNA splicing, with two modes indicating the current and future state. [ 1 ] It is a method used to predict the future gene expression of a cell based on the measurement of both spliced and unspliced transcripts of mRNA. [ 2 ] RNA velocity coul...
https://en.wikipedia.org/wiki/RNA_velocity
The RNA world is a hypothetical stage in the evolutionary history of life on Earth in which self-replicating RNA molecules proliferated before the evolution of DNA and proteins . [ 1 ] The term also refers to the hypothesis that posits the existence of this stage. Alexander Rich first proposed the concept of the RNA wo...
https://en.wikipedia.org/wiki/RNA_world
The Route Network Definition File (RNDF) specifies accessible road segments and provides information such as waypoints , stop sign locations, lane widths, checkpoint locations, and parking spot locations. The route network has no implied start or end point. In addition to road segments, the RNDF specifies free-travel ‘...
https://en.wikipedia.org/wiki/RNDF
9604 56736 ENSG00000013561 ENSMUSG00000060450 Q9UBS8 Q9JI90 NM_183401 NM_001361266 NM_001361267 NM_001361268 NM_001361269 NP_899648 NP_001348195 NP_001348196 NP_001348197 NP_001348198 E3 ubiquitin-protein ligase RNF14 is an enzyme that in humans is encoded by the RNF14 gene . [ 5 ] [ 6 ] [ 7 ] The protein en...
https://en.wikipedia.org/wiki/RNF14
In chemistry , amines ( / ə ˈ m iː n , ˈ æ m iː n / , [ 1 ] [ 2 ] UK also / ˈ eɪ m iː n / [ 3 ] ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair . Formally, amines are derivatives of ammonia ( NH 3 in which the bond angle between the nitrogen and hydrogen is 107°), wherein one o...
https://en.wikipedia.org/wiki/RNH2
6053 n/a n/a n/a n a n/a n/a n/a n/a n/a RNR2 ( RNA, ribosomal 45S cluster 2 [ 2 ] ) is a human ribosomal DNA gene located on Chromosome 14 . Tandem copies of this gene form one of five nucleolus organizer regions in the human genome, they are located on the chromosomes 13 ( RNR1 ), 14 ( RNR2 ), 15 ( RNR3 ), ...
https://en.wikipedia.org/wiki/RNR2
RNU2-2 syndrome is a neurodevelopmental disorder caused by de novo variants in the human gene RNU2-2 , which encodes an RNA component of the major spliceosome . It is characterized by epilepsy , intellectual disability, autistic behavior, microcephaly , hypotonia and hyperventilation . [ 1 ] The syndrome is an autosom...
https://en.wikipedia.org/wiki/RNU2-2_syndrome
RNU4-2 Syndrome or ReNU syndrome is a neurodevelopmental disorder caused by de novo variants in the human gene RNU4-2 , which encodes an RNA component of the major spliceosome . It is characterized by hypotonia , global developmental delay , severely impaired intellectual development with poor or absent speech, delayed...
https://en.wikipedia.org/wiki/RNU4-2_syndrome
RNase H-dependent PCR (rhPCR) [ 1 ] is a modification of the standard PCR technique. In rhPCR, the primers are designed with a removable amplification block on the 3’ end. Amplification of the blocked primer is dependent on the cleavage activity of a hyperthermophilic archaeal Type II RNase H enzyme during hybridizat...
https://en.wikipedia.org/wiki/RNase_H-dependent_PCR
ROMeo [ 1 ] [ 2 ] Rigorous Online Modelling and Equation Based Optimization is an advanced online chemical process optimizer of SimSci, a brand of Aveva software [ 3 ] It is mainly used by process engineers in the chemical , petroleum and natural gas industries. It includes a chemical component library , thermodynamic...
https://en.wikipedia.org/wiki/ROMeo_(process_optimizer)
Rho-related GTPases from plants, otherwise known as ROPs, are involved in cell polarity through the regulation of cytoskeleton components like actin and microtubules . [ 1 ] [ 2 ] Unlike mammalian cells, plant cells do not contain heterotrimeric G proteins like Cdc42 , Rac, and Rho that are known to regulate cellular p...
https://en.wikipedia.org/wiki/ROP_GTPase
ROSAT (short for Röntgensatellit ; in German X-rays are called Röntgenstrahlen, in honour of Wilhelm Röntgen ) was a German Aerospace Center -led satellite X-ray telescope , with instruments built by West Germany , the United Kingdom and the United States. It was launched on 1 June 1990, on a Delta II rocket from Cape ...
https://en.wikipedia.org/wiki/ROSAT
The resistivity of solvent extract ( ROSE ) test is a test for the presence and average concentration of soluble ionic contaminants, for example on a printed circuit board (PCB). [ 1 ] [ 2 ] [ 3 ] [ 4 ] It was developed in the early 1970s. [ 5 ] Some manufacturers use it as part of Six Sigma processes. [ 3 ] Some mode...
https://en.wikipedia.org/wiki/ROSE_test
Reliable Quantum Operations Per Second (rQOPS) is a metric that measures the capabilities and error rates of a quantum computer . It combines several key factors to measure how many reliable operations a computer can execute in a single second: logical error rates, clock speed , and number of reliable qubits . [ 1 ] [ ...
https://en.wikipedia.org/wiki/RQOPS
The Rice–Ramsperger–Kassel–Marcus ( RRKM ) theory is a theory of chemical reactivity . [ 1 ] [ 2 ] [ 3 ] It was developed by Rice and Ramsperger in 1927 [ 4 ] and Kassel in 1928 [ 5 ] (RRK theory [ 6 ] ) and generalized (into the RRKM theory) in 1952 by Marcus [ 7 ] who took the transition state theory developed by Eyr...
https://en.wikipedia.org/wiki/RRKM_theory
RRT Global is an international company that specializes in the development of technologies for oil refining process. The company's CEO , Douglas Harris, is a former vice president of TNK-BP . [ 3 ] [ 4 ] The company is a resident of the Energy Efficient Technologies cluster of the Skolkovo Foundation . [ 5 ] [ 6 ] [ 7 ...
https://en.wikipedia.org/wiki/RRT_Global
The Xbox 360 video game console was subject to a number of technical problems and failures, some as a result of design flaws. Some issues could be identified by a pattern of red lights on the front face of the console; these colloquially became known as the " Red Ring of Death " or the " RRoD ". [ 1 ] [ 2 ] There were ...
https://en.wikipedia.org/wiki/RRoD
The blue screen of death ( BSoD ) – or blue screen error , blue screen , fatal error , bugcheck , and officially known as a stop error [ 1 ] [ 2 ] [ 3 ] – is a critical error screen displayed by the Microsoft Windows operating systems to indicate a system crash , in which the operating system reaches a critical condit...
https://en.wikipedia.org/wiki/RSOD
The RSPB Medal is awarded annually by the Royal Society for the Protection of Birds . [ 1 ] According to the RSPB: The RSPB Medal is the Society's most prestigious award. It is presented to an individual in recognition of wild bird protection and countryside conservation. It is usually awarded annually to one or occa...
https://en.wikipedia.org/wiki/RSPB_Medal
The blue screen of death ( BSoD ) – or blue screen error , blue screen , fatal error , bugcheck , and officially known as a stop error [ 1 ] [ 2 ] [ 3 ] – is a critical error screen displayed by the Microsoft Windows operating systems to indicate a system crash , in which the operating system reaches a critical condit...
https://en.wikipedia.org/wiki/RSoD
The plug flow reactor model ( PFR , sometimes called continuous tubular reactor , CTR , or piston flow reactors ) is a model used to describe chemical reactions in continuous, flowing systems of cylindrical geometry. The PFR model is used to predict the behavior of chemical reactors of such design, so that key reactor ...
https://en.wikipedia.org/wiki/RTD_studies_of_plug_flow_reactor
RTL 24 started as a mobile TV news channel on 5 June 2008. It was available through KPN DVB-H . [ 1 ] Its broadcast as a mobile TV channel stopped when KPN ceased its DVB-H services on 1 June 2011. [ 2 ] After a short break, RTL 24 re-launched as a mobile app for smart phones , tablet computers and other mobile device...
https://en.wikipedia.org/wiki/RTL_24
RTMI ( Radio Telefono Mobile Integrato ) was the first mobile communication service in Italy , started in 1973. It operated on the 160 MHz frequency band and was used by a few people working in the public sector (public administrations and defense officials). In the 1980s, the Radio Telephone Mobile (RTM) emerged, whic...
https://en.wikipedia.org/wiki/RTMI
RVT-802 ( allogeneic cultured postnatal thymus-derived tissue ) is a medication being developed by Enzyvant Therapeutics Ireland Limited for the treatment of congenital athymia (absence of a thymus gland), especially in the context of DiGeorge syndrome . Enzyvant licensed the technology underlying RVT-802 from Duke Un...
https://en.wikipedia.org/wiki/RVT-802
RV Rachel Carson is a research vessel owned and operated by the University of Maryland 's Center for Environmental Science, named in honor of the marine biologist and writer Rachel Carson . The 81-foot aluminum-hulled vessel is an extended and modified Challenger class fast research vessel, designed by marine architec...
https://en.wikipedia.org/wiki/RV_Rachel_Carson_(2008)
R/V Rachel Carson is a research vessel owned and operated by the University of Washington 's School of Oceanography, named in honor of the marine biologist and writer Rachel Carson . The vessel is part of the UNOLS fleet. It is capable of conducting operations within the Salish Sea and coastal waters of the western Uni...
https://en.wikipedia.org/wiki/RV_Rachel_Carson_(2017)
RV Song of the Whale is a research vessel owned by Marine Conservation Research International and operated by Marine Conservation Research Ltd. The 70-foot vessel was designed specifically to carry out research on cetaceans (and other marine fauna) using benign research techniques such as passive acoustic monitoring. ...
https://en.wikipedia.org/wiki/RV_Song_of_the_Whale
RW3 Technologies is a software company that provides SaaS Intelligent in store execution, data driven field sales, survey, Dashboard/reporting consumer packaged goods (CPG) industryand Online — Instore Competitive Pricing to Retailers. It is headquartered in Austin Texas . RW3 Technologies was founded in the Bay Area...
https://en.wikipedia.org/wiki/RW3_Technologies
An RX meter is used to measure the separate resistive and reactive components of reactive parallel Z network. The two variable frequency oscillators track each other at frequencies 100 kHz apart. The output of a 0.5-250 MHz oscillator, [ 1 ] F1, is fed into a bridge. When the impedance network to be measured is connec...
https://en.wikipedia.org/wiki/RX_meter
R is the ratio of the hadronic cross section to the muon cross section in electron – positron collisions : where the superscript (0) indicates that the cross section has been corrected for initial state radiation. R is an important input in the calculation of the anomalous magnetic dipole moment . [ 1 ] Experimental v...
https://en.wikipedia.org/wiki/R_(cross_section_ratio)
R bodies (from refractile bodies , also R-bodies ) are polymeric protein inclusions formed inside the cytoplasm of bacteria . [ 1 ] Initially discovered in kappa particles , bacterial endosymbionts of the ciliate Paramecium , R bodies (and genes encoding them) have since been discovered in a variety of taxa. [ 2 ] At ...
https://en.wikipedia.org/wiki/R_bodies
Radium bromide is the bromide salt of radium , with the formula RaBr 2 . It is produced during the process of separating radium from uranium ore . This inorganic compound was discovered by Pierre and Marie Curie in 1898, and the discovery sparked a huge interest in radiochemistry and radiotherapy . Since elemental radi...
https://en.wikipedia.org/wiki/RaBr2
Radium chloride is an inorganic compound with the chemical formula Ra Cl 2 . It is a radium salt of hydrogen chloride . It was the first radium compound isolated in a pure state. Marie Curie and André-Louis Debierne used it in their original separation of radium from barium . The first preparation of radium metal was b...
https://en.wikipedia.org/wiki/RaCl2
Rabatment of the rectangle is a compositional technique used as an aid for the placement of objects or the division of space within a rectangular frame, or as an aid for the study of art. Every rectangle contains two implied squares, each consisting of a short side of the rectangle, an equal length along each longer s...
https://en.wikipedia.org/wiki/Rabatment_of_the_rectangle
Rabattement (also rabatment ) is a rotation of a planar object around a folding line (using the line like a hinge ) in order to align the object with another plane. [ 1 ] [ 2 ] [ 3 ] Rabattement is used in technical drawings to produce developments (patterns, templates). In these drawings the object is "unfolded" to la...
https://en.wikipedia.org/wiki/Rabattement_(drafting)
Rabbi Nehemiah was a rabbi who lived circa 150 AD (fourth generation of tannaim ). He was one of the great students of Rabbi Akiva , and one of the rabbis who received semicha from R' Judah ben Baba The Talmud equated R' Nechemiah with Rabbi Nehorai : "His name was not Rabbi Nehorai, but Rabbi Meir." [ 1 ] His son, ...
https://en.wikipedia.org/wiki/Rabbi_Nehemiah
The State Barrier Fence of Western Australia , [ 1 ] formerly known as the Rabbit-Proof Fence , the State Vermin Fence , and the Emu Fence , is a pest-exclusion fence constructed between 1901 and 1907 to keep rabbits , and other agricultural pests from the east, out of Western Australian pastoral areas. [ 2 ] There ar...
https://en.wikipedia.org/wiki/Rabbit-proof_fence
A rabbit hybridoma is a hybrid cell line formed by the fusion of an antibody producing rabbit B cell with a cancerous B-cell ( myeloma ). The rabbit immune system has been documented as a vehicle for developing antibodies with higher affinity and more diverse recognition of many molecules including phospho-peptides, c...
https://en.wikipedia.org/wiki/Rabbit_hybridoma
In 1617 a treatise in Latin titled Rabdologiæ and written by John Napier was published in Edinburgh. Printed three years after his treatise on the discovery of logarithms and in the same year as his death, it describes three devices to aid arithmetic calculations. The devices themselves don't use logarithms, rather th...
https://en.wikipedia.org/wiki/Rabdology
The Rabi frequency is the frequency at which the probability amplitudes of two atomic energy levels fluctuate in an oscillating electromagnetic field. It is proportional to the transition dipole moment of the two levels and to the amplitude ( not intensity ) of the electromagnetic field . Population transfer between th...
https://en.wikipedia.org/wiki/Rabi_frequency
Rabi resonance method is a technique developed by Isidor Isaac Rabi for measuring the nuclear spin, in which an atom is placed in a static magnetic field and a perpendicular rotating magnetic field. When only the static magnetic field (B 0 ) is turned on, the spin will precess around it with Larmor frequency ν 0 and t...
https://en.wikipedia.org/wiki/Rabi_resonance_method
The Rabinovich–Fabrikant equations are a set of three coupled ordinary differential equations exhibiting chaotic behaviour for certain values of the parameters . They are named after Mikhail Rabinovich and Anatoly Fabrikant , who described them in 1979. The equations are: [ 1 ] where α , γ are constants that control ...
https://en.wikipedia.org/wiki/Rabinovich–Fabrikant_equations
The Racah parameters are a set of parameters used in atomic and molecular spectroscopy to describe the amount of total electrostatic repulsion in an atom that has multiple electrons . When an atom has more than one electron, there will be some electrostatic repulsion between the electrons. The amount of repulsion vari...
https://en.wikipedia.org/wiki/Racah_parameter
In mathematics , Racah polynomials are orthogonal polynomials named after Giulio Racah , as their orthogonality relations are equivalent to his orthogonality relations for Racah coefficients . The Racah polynomials were first defined by Wilson (1978) and are given by There are three generating functions for x ∈ { 0 ,...
https://en.wikipedia.org/wiki/Racah_polynomials
The Racah seniority number (seniority quantum number) ν {\displaystyle \nu } was introduced by Giulio Racah for the classification of electrons in an atomic configuration. [ 1 ] The "seniority number", in a loosing statement, is quantum number additional to the total angular momentum L {\displaystyle L} and total spin...
https://en.wikipedia.org/wiki/Racah_seniority_number
Race and health refers to how being identified with a specific race influences health. Race is a complex concept that has changed across chronological eras and depends on both self-identification and social recognition. [ 1 ] In the study of race and health, scientists organize people in racial categories depending on ...
https://en.wikipedia.org/wiki/Race_and_health
Racemic acid is an old name for an optically inactive or racemic form of tartaric acid . It is an equal mixture of two mirror-image isomers ( enantiomers ), optically active in opposing directions. Racemic acid does not occur naturally in grape juice, although L-tartaric acid does. Tartaric acid's sodium-ammonium salt...
https://en.wikipedia.org/wiki/Racemic_acid
Racemic crystallography is a technique used in structural biology where crystals of a protein molecule are developed from an equimolar mixture of an L-protein molecule of natural chirality and its D-protein mirror image. [ 1 ] [ 2 ] L-protein molecules consist of 'left-handed' L- amino acids and the achiral amino acid ...
https://en.wikipedia.org/wiki/Racemic_crystallography
In chemistry , a racemic mixture or racemate ( / r eɪ ˈ s iː m eɪ t , r ə -, ˈ r æ s ɪ m eɪ t / [ 1 ] ) is a mixture that has equal amounts (50:50) of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as racemates. The fir...
https://en.wikipedia.org/wiki/Racemic_mixture
In chemistry , racemization is a conversion, by heat or by chemical reaction, of an optically active compound into a racemic (optically inactive) form. This creates a 1:1 molar ratio of enantiomers and is referred to as a racemic mixture (i.e. contain equal amount of (+) and (−) forms). Plus and minus forms are called ...
https://en.wikipedia.org/wiki/Racemization
In calculus , the racetrack principle describes the movement and growth of two functions in terms of their derivatives . This principle is derived from the fact that if a horse named Frank Fleetfeet always runs faster than a horse named Greg Gooseleg, then if Frank and Greg start a race from the same place and the sa...
https://en.wikipedia.org/wiki/Racetrack_principle
A racetrack problem is a specific instance of a type of race condition . A racetrack problem is a flaw in a system or process whereby the output and/or result of the process is unexpectedly and critically dependent on the sequence or timing of other events that run in a circular pattern. This problem is semantically di...
https://en.wikipedia.org/wiki/Racetrack_problem
Racewood is a British company that specialises in creating horse riding simulators. It was established in 1990. Racewood simulators are seen in riding schools as well as gyms and tack shops. [ 1 ] They are also sometimes brought in to horse expeditions and shows such as the Grand National , Horse Of The Year Show and ...
https://en.wikipedia.org/wiki/Racewood
Rachna Malayalam is considered as the first computer operating system in Malayalam language and the first such system in a regional language in India . It was launched on February 16, 2006. [ 1 ] The operating system, developed by four people in Kerala , is in the Linux platform and is an open software . This softwar...
https://en.wikipedia.org/wiki/Rachana_Malayalam
The Rachel Carson Prize is awarded annually by the Society for Social Studies of Science , an international academic association based in the United States. It is given for a book "of social or political relevance" in the field of science and technology studies . This prize was created in 1996. [ 1 ]
https://en.wikipedia.org/wiki/Rachel_Carson_Prize_(academic_book_prize)
Moulay Rachid Idrissi ( Arabic : مولاي رشيد الإدريسي ; 1939 – October 18, 1971) was a Moroccan nuclear chemist and engineer. Idrissi gained notoriety after his work on the recovery of uranium from phosphates , where he discovered a significant amount of uranium in Moroccan phosphates. Shortly after this discovery, he d...
https://en.wikipedia.org/wiki/Rachid_Idrissi
According to the National Science Foundation (NSF), women and racial minorities are underrepresented in science, technology, engineering, and mathematics (STEM). [ 1 ] Scholars, governments, and scientific organizations from around the world have noted a variety of explanations contributing to this lack of racial diver...
https://en.wikipedia.org/wiki/Racial_diversity_and_discrimination_in_STEM_fields
Ractopamine ( / r æ k ˈ t ɒ p ə m aɪ n , - m iː n / ) is an animal feed additive used to promote leanness and increase food conversion efficiency in farmed animals in several countries, but banned in others. Pharmacologically, it is a phenol -based TAAR1 agonist and β adrenoreceptor agonist that stimulates β 1 and β 2 ...
https://en.wikipedia.org/wiki/Ractopamine
The RadBall is a 140-millimetre (5.5-inch) diameter deployable, passive, non-electrical gamma hot-spot imaging device that offers a 360 degree view of the deployment area. The device is particularly useful in instances where the radiation fields inside a nuclear facility are unknown but required in order to plan a suit...
https://en.wikipedia.org/wiki/RadBall
Radappertization is a form of food irradiation which applies a dose of ionizing radiation sufficient to reduce the number and activity of viable microorganisms to such an extent that very few, if any, are detectable in the treated food by any recognized method ( viruses being excepted). No microbial spoilage or toxici...
https://en.wikipedia.org/wiki/Radappertization
Radar is a system that uses radio waves to determine the distance ( ranging ), direction ( azimuth and elevation angles ), and radial velocity of objects relative to the site. It is a radiodetermination method [ 1 ] used to detect and track aircraft , ships , spacecraft , guided missiles , motor vehicles , map weather ...
https://en.wikipedia.org/wiki/Radar
A radar altimeter ( RA ), also called a radio altimeter ( RALT ), electronic altimeter , reflection altimeter , or low-range radio altimeter ( LRRA ), measures altitude above the terrain presently beneath an aircraft or spacecraft by timing how long it takes a beam of radio waves to travel to ground, reflect, and retur...
https://en.wikipedia.org/wiki/Radar_altimeter
Radar ornithology is the use of radar technology in studies of bird migration and in approaches to prevent bird strikes particularly to aircraft. The technique was developed from the observations of pale wisps seen moving on radar during the Second World War. These were termed as "angels", "ghosts", or "phantoms" in Br...
https://en.wikipedia.org/wiki/Radar_ornithology