In mathematics, by sigma function one can mean one of the following:
* The sum-of-divisors function σ"a"("n"), an
*
* Rado's sigma function, see
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Kronecker's sigma function — Let D be the domain of the Cartesian product X times X, for a set X, then the Kronecker s sigma function with respect to X is a function from D to the set {0,1} such that it is equal to the characteristic function on D.ee also*Sigma function … Wikipedia
Sigma (disambiguation) — Sigma may refer to: * Sigma (Σ, σ, or ς), of the Greek alphabetCompanies: * Sigma TV a television channel in Cyprus * Sigma Company, an Australian company. Its main operations include Pharmaceuticals and Pharmacies * Sigma Corporation, a Japanese … Wikipedia
Sigma-Faktoren — (σ Faktoren) sind bakterielle Proteine, welche für die Initiation der Transkription notwendig sind. In der Regel sind Sigma Faktoren in der Zelle an die RNA Polymerase gebunden. Eine vollständige bakterielle Polymerase mit gebundenem Sigma Faktor … Deutsch Wikipedia
Sigma receptor — The sigma receptors σ1 and σ2 are receptors which bind to ligands such as 4 PPBP, [cite journal |author=Yang S, Bhardwaj A, Cheng J, Alkayed NJ, Hurn PD, Kirsch JR |title=Sigma receptor agonists provide neuroprotection in vitro by preserving bcl… … Wikipedia
Sigma-algebra — In mathematics, a σ algebra (also sigma algebra, σ field, sigma field) is a technical concept for a collection of sets satisfying certain properties. The main use of σ algebras is in the definition of measures; specifically, the collection of… … Wikipedia
Sigma additivity — In mathematics, additivity and sigma additivity of a function defined on subsets of a given set are abstractions of the intuitive properties of size (length, area, volume) of a set. Contents 1 Additive (or finitely additive) set functions 2 σ… … Wikipedia
Sigma Chi — Infobox Fraternity letters = ΣΧ name = Sigma Chi nickname = Sigs crest = motto = In Hoc Signo Vinces ( In This Sign You Will Conquer ) colors = Blue and Old Gold symbol = The White Cross flower = White Rose founded = birth date and age|1855|6|28… … Wikipedia
Sigma factor — A sigma factor ( sigma; factor) is a prokaryotic transcription initiation factor that enables specific binding of RNA polymerase to gene promoters. Different sigma factors are activated in response to different environmental conditions. Every… … Wikipedia
Sigma-1 receptor — protein Name=opioid receptor, sigma 1 caption= width= HGNCid=8157 Symbol=OPRS1 AltSymbols= EntrezGene=10280 OMIM=601978 RefSeq=NM 147157 UniProt=Q2TSD1 PDB= ECnumber= Chromosome=9 Arm= Band= LocusSupplementaryData=The sigma 1 receptor is a… … Wikipedia
Sigma-Faktor — Der Sigma Faktor (σ Faktor) ist ein bakterielles Protein, welches für die Initiation der Transkription notwendig ist. In der Regel sind Sigma Faktoren in der Zelle an die RNA Polymerase gebunden. Eine vollständige bakterielle Polymerase mit… … Deutsch Wikipedia
