Arenesubstitutionpatterns are part of organic chemistry IUPAC nomenclature and pinpoint the position of substituent s other than hydrogen in relation to each other on an aromatic hydrocarbon . Ortho , meta , and para substitution Image Ortho meta para.svg thumb 150px left Main arenesubstitutionpatterns. See also Electrophilic aromatic substitution In ortho substitution , two substituents occupy positions next to each other, which may be numbered 1 and 2. In the diagram, these positions are marked R and ortho. In meta substitution the substituents occupy positions 1 and 3 corresponding to R and meta in the diagram . In para substitution , the substituents occupy the opposite ends positions 1 and 4, corresponding to R and para in the diagram . The toluidine s serve as an example for these three types of substitution. clear Ipso , meso , and peri substitution gallery Image Ipso Substitution V.1.svg ipso substitution. Image Meso Substitution V.1.svg meso substitution. Image Peri Substitution V.1.svg peri substitution. gallery Ipso substitution describes two substituents sharing the same ring position in an intermediate compound in an electrophilic aromatic substitution . Meso substitution refers to the substituents occupying a benzyl ic position. It is observed in compounds such as calixarene s and acridine s. Peri substitution occurs in naphthalene s for substituents at the 1 and 8 positions. Cine and tele substitution In cine substitution , the entering group takes up a position adjacent to that occupied by the leaving group . For example, cine substitution is observed in aryne chemistry. ref GoldBookRef title cine substitution file C01081 ref Tele substitution occurs when the new position is more than one atom away on the ring. ref GoldBookRef title tele substitution file T06256 ref Origins The prefixes ortho , meta , and para are all derived from Greek, meaning straight ... Terephthals ure.svg terephthalic acid gallery References Reflist DEFAULTSORT AreneSubstitutionPatterns ... more details
selfref For substitution of a template on Wikipedia, see Wikipedia Substitution wiktionary substitutionSubstitution may refer to Sciences Substitution reaction , where a functional group in a chemical compound is replaced by another group Substitution logic , a syntactic transformation on strings of symbols of a formal language Substitution of variables Substitution cipher , a method of encryption String substitution , a mapping of letters in an alphabet to languages Substitution method , a method of measuring the transmission loss of a fiber Base pair substitution or point mutation, a type of mutation Substitution, a process in which an allele arises and undergoes fixation population genetics fixation Other uses Substitution law , the replacement of a judge Substitution poetry , a variation in poetic scansion Substitution song Substitution song , a song by Silversun Pickups Substitution sport , where a sports team is able to change one player for another during a match Substitution theatre , an acting methodology See also Substitute disambiguation Integration by substitution , a method for finding antiderivatives and integrals Substitution therapy or opiate replacement therapy Penal substitution , a theory of the atonement within Christian theology Chord substitution , the use of a chord in the place of another related chord Import substitution industrialization , a trade and economic policy Simultaneous substitution , a practice requiring Canadian television distribution companies to substitute a non local station signal with the local signal disambig cs Substituce da Substitution de Substitution es Sustituci n fr Substitution it Sostituzione nl Substitutie ja nn Substitusjon ru sk Substit cia sr fi Substituutio sv Substitution uk ... more details
Arene or Ar n or Ar ne may refer to an aromatic hydrocarbon Arene gastropod Arene gastropod , a genus of marine snails in the family Areneidae Arene mythology , the wife of Aphareus and mother of Idas and Lynceus in Greek mythology Arene, Elis , an ancient Greek town in Elis, Greece known also as Makistos, Samia or Samikon Arene surname , a French family name of the Provence region disambig de Arene el ... more details
Italic title Taxobox name Arene fossil range image Arene cruentatus 001.jpg image caption Shell and operculum gastropod operculum of Arene cruentata regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae genus Arene genus authority Adams name Adams , 1845 subdivision ranks Species subdivision See text Arene is a genus ... mollusc s in the family biology family Areneidae . The genus Arene and also the genus Cinysca ... Scripta 37 5 483 506. doi 10.1111 j.1463 6409.2008.00341.x ref Species Species within the genus Arene include ref name WoRMS WoRMS 2010 . Arene Adams, 1845. In Bouchet, P. Gofas, S. Rosenberg, G. 2010 ... aphia.php?p taxdetails&id 413481 on 1 January 2011 ref Arene bairdii Dall, 1889 Arene bitleri Olsson & McGinty, 1958 Arene boucheti Leal, 1991 Arene brasiliana Dall, 1927 Arene briareus Dall, 1881 Arene centrifuga Dall, 1896 Arene cruentata M hlfeld, 1824 Arene curacoana Pilsbry, 1934 Arene flexispina Leal & Coelho, 1985 Arene laguairana Weisbord, 1962 Arene microforis Dall, 1889 Arene miniata Dall, 1889 Arene pulex Faber, 2009 Arene riisei Rehder, 1943 Arene tamsiana Philippi, 1852 Arene tricarinata Stearns, 1872 Arene variabilis Dall, 1889 Arene venustula Aguayo & Rehder, 1936 Other species include Verify source date April 2010 Arene adusta J. H. McLean, 1970 Arene balboai Strong & Leo George Hertlein Hertlein , 1939 Arene brasiliana W.H. Dall Dall , 1927 Arene californica W.H. Dall Dall , 1908 Arene carinata Phillip Pearsall Carpenter Carpenter , 1857 Arene coronadensis Stohler, 1959 Macrarene coronadensis Arene diegensis J. H. McLean, 1964 Arene farallonensis A. G. Smith, 1952 Arene ferruginosa J. H. McLean, 1970 Arene fricki Joseph Charles Hippolyte Crosse Crosse , 1865 Arene lepidotera J. H. Mclean, 1970 Arene lucasensis Strong, 1933 Arene miniata W.H. Dall Dall , 1889 Arene stellata J. H. McLean, 1970 Arene venusta Woodring, 1928 References Reflist Category Areneidae ... more details
Italic title Taxobox name Arene bairdii image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. bairdii binomial Arene bairdii binomial authority Dall, 1889 synonyms ref synonyms Arene bairdii is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419468 Arene bairdii Dall, 1889 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Bairdii Category Areneidae Vetigastropoda stub vi Arene bairdii ... more details
Italic title Taxobox name Arene briareus image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. briareus binomial Arene briareus binomial authority Dall, 1881 synonyms ref synonyms Arene briareus is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419469 Arene briareus Dall, 1881 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Briareus Category Areneidae Vetigastropoda stub vi Arene briareus ... more details
Italic title Taxobox name Arene centrifuga image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. centrifuga binomial Arene centrifuga binomial authority Dall, 1896 synonyms ref synonyms Arene centrifuga is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419470 Arene centrifuga Dall, 1896 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Centrifuga Category Areneidae Vetigastropoda stub vi Arene centrifuga ... more details
Italic title Taxobox name Arene microforis image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. microforis binomial Arene microforis binomial authority Dall, 1889 synonyms ref synonyms Arene microforis is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419472 Arene microforis Dall, 1889 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Microforis Category Areneidae Vetigastropoda stub vi Arene microforis ... more details
Italic title Taxobox name Arene riisei image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. riisei binomial Arene riisei binomial authority Rehder, 1943 synonyms ref synonyms Arene riisei is a species of small sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419473 Arene riisei Rehder, 1943 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Riisei Category Areneidae Vetigastropoda stub vi Arene riisei ... more details
Italic title Taxobox name Arene tricarinata image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. tricarinata binomial Arene tricarinata binomial authority Stearns, 1872 synonyms ref synonyms Arene tricarinata is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419474 Arene tricarinata Stearns, 1872 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Tricarinata Category Areneidae Vetigastropoda stub vi Arene tricarinata ... more details
Italic title Taxobox name Arene variabilis image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. variabilis binomial Arene variabilis binomial authority Dall, 1889 synonyms ref synonyms Arene variabilis is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419475 Arene variabilis Dall, 1889 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Variabilis Category Areneidae Vetigastropoda stub vi Arene variabilis ... more details
Italic title Taxobox image Arene cruentatus 001.jpg image caption Lateral view of gastropod shell shell and operculum gastropod operculum of Arene cruentata regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. cruentata binomial Arene cruentata binomial authority M hlfeld, 1824 synonyms ref ref name WoRMS synonyms Trochus cruentatus small M hlfeld, 1824 small Arene cruentata is a species of small sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419471 Arene cruentata M hlfeld, 1824 5 October 2010 ref Description Empty section date April 2010 Distribution This species occurs in Florida , the Gulf of Mexico and the Caribbean Sea . References reflist External links http www.malacolog.org search.php?nameid 980 Malacolog info gallery File Arene cruentatus 003.jpg Apical view of shell File Arene cruentatus 002.jpg Umbilical view of shell, also showing operculum gallery Use dmy dates date January 2011 DEFAULTSORT Arene Cruentata Category Areneidae Vetigastropoda stub vi Arene cruentata ... more details
Italic title Taxobox name Arene pulex image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. pulex binomial Arene pulex binomial authority Faber, 2009 ref WRMS source 140544 Faber 2009 . Miscellanea Malacologica 3 6 121 125 19 April 2010 ref synonyms ref synonyms Arene pulex is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 457313 Arene pulex Faber, 2009 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Pulex Category Areneidae Vetigastropoda stub vi Arene pulex ... more details
Italic title Taxobox name Arene venustula image image caption regnum Animal ia phylum Mollusca classis Gastropoda unranked superfamilia clade Vetigastropoda superfamilia Angarioidea familia Areneidae subfamilia genus Arene gastropod Arene species A. venustula binomial Arene venustula binomial authority Aguayo & Rehder, 1936 synonyms ref synonyms Arene venustula is a species of sea snail , a marine gastropod mollusk in the family biology family Areneidae . ref name WoRMS WRMS species 419476 Arene venustula Aguayo & Rehder, 1936 19 April 2010 ref Description Empty section date April 2010 Distribution Empty section date April 2010 References reflist External links Use dmy dates date January 2011 DEFAULTSORT Arene Venustula Category Areneidae Vetigastropoda stub vi Arene venustula ... more details
Arene is a French people French surname family name of the Provence region with the same origin as the Spanish language Spanish Arenas and Italian language Italian Arena, all derived from the Latin root word h arena , meaning sand . By family tradition, the sand in question was that of the Ancient Rome Roman arena or colosseum , thus making the original bearer a gladiator . More likely, however, the name simply signifies a person who lived at a sandy place. List of people with this surname Paul Ar ne 1843 1896 , Proven al poet and French writer DEFAULTSORT Arene Surname Category Surnames surname stub ... more details
Substitution principle can refer to several things Substitution principle mathematics Substitution principle sustainability Liskov substitution principle computer science disambig ... more details
Refimprove date March 2009 In cryptography , a substitution cipher is a method of encryption by which .... The receiver deciphers the text by performing an inverse substitution. Substitution ciphers can .... By contrast, in a substitution cipher, the units of the plaintext are retained in the same sequence in the ciphertext, but the units themselves are altered. There are a number of different types of substitution cipher. If the cipher operates on single letters, it is termed a simple substitution ... uses fixed substitution over the entire message, whereas a polyalphabetic cipher uses a number ... of several possibilities in the ciphertext and vice versa. Simple substitution Image ROT13.png thumb 300px right ROT13 is a Caesar cipher , a type of substitution cipher. In ROT13, the alphabet is rotated 13 steps. Substitution over a single letter simple substitution can be demonstrated by writing out the alphabet in some order to represent the substitution. This is termed a substitution alphabet ... system. ref Example MAT would be used to represent 120. Security for simple substitution ciphers A disadvantage ... simple substitution. In practice, typically about 50 letters are needed, although some messages can be broken with fewer if unusual patterns are found. In other cases, the plaintext can be contrived .... Homophonic substitution This section is linked from Homophonic substitution cipher . See WP ... on substitution ciphers was to disguise plaintext letter frequencies by homophony . In these ciphers ... is to use a numeric substitution alphabet . Another method consists of simple variations ... dignitaries, this cipher combined a small codebook with large homophonic substitution tables ... checkerboard are types of homophonic cipher. Polyalphabetic substitution Main Polyalphabetic cipher Polyalphabetic substitution ciphers were first described in 1467 by Leone Battista Alberti in the form ... cipher. All such ciphers are easier to break than once believed, as substitution alphabets are repeated ... more details
Sensory substitution means to transform the characteristics of one sensory modality into stimuli of another sensory modality. It is hoped that sensory substitution systems can help handicapped people by restoring ... from a functioning sensory modality. A sensory substitution system consists of three parts a sensor ... augmentation . Sensory substitution concerns human perception and the neuroplasticity plasticity of the human ... . History Sensory Substitution was introduced in the 60s by Paul Bach y Rita as a means of using ... F, White B, Scadden L. 1969 . Vision substitution by tactile image projection. . Nature , 221 963 ... VLE07U 0 ref The first sensory substitution system was developed by Bach y Rita et al. as a means ... substitution studies. . Annals of New York Academic Sciences , 1013 83 91. ref After this historic invention, sensory substitution has been the basis of many studies investigating perceptive and cognitive neuroscience . Since then, sensory substitution has contributed to the study of brain function ... mechanisms in sensory substitution of vision a contribution to the study of human perception. . Journal of Integrative Neuroscience , 4 4 489 503. ref Physiology of sensory substitution When a person ... to brain. ref name bach Bach y Rita P, Kercel SW. 2003 . Sensory substitution and the human machine ... for the final perception, sensory substitution is possible. During sensory substitution an intact ... can perceive to see. With sensory substitution, information gained from one sensory modality can reach brain structures physiologically related to other sensory modalities. Touch to visual sensory substitution ... Mechanisms in Sensory Substitution , Academic Press New York 1972. ref We can also have touch to touch sensory substitution where information from touch receptors of one region can be used to perceive ... 1995. ref Technological support In order to have sensory substitution and stimulate the brain without ... to the brain for visual and auditory perception. This type of sensory substitution is only possible ... more details
. The tritone substitution is one of the most common substitutions found in jazz and was the precursor to more complex substitutionpatterns like Coltrane changes . Tritone substitutions are sometimes .... In jazz , a tritone substitution ref name Sarath ref name Coker 81 tritone substitute dominant ... of Solo Bass The Chordal Approach , p.17. ISBN 0786606533. ref is the chord substitution of a chord ... . Substitute dominant A substitute dominant is a chord substitution for a chord with a dominant ... A Beethoven.mid Play the cadence with the substitute, and then without. Tritone substitution Analysis .... audio Tritone substitution.mid Play A tritone substitution is the use in a chord progression ..., a tritone substitution involves replacing V sup 7 sup with music b V sup 7 sup V music b II sup 7 ..., D music flat sup 7 sup is the tritone substitution for G sup 7 sup . From traditional jazz harmony , tritone substitution works because the two chords share two pitches namely, the third chord ..., in its tritone substitution, D music flat sup 7 sup , the third is an F and the seventh is C music ... seventh chord is itself a tritone. Image Tritone substitution common tones.png thumb right ... F music flat , and then G music flat sup 7 sup Audio Tritone substitution common tones.ogg Play . Edward ... notate the substitution as an augmented sixth chord on music flat 2. The augmented sixth chord can .... ref Below is the original dominant tonic progression, the same progression with the tritone substitution, and the same progression with the substitution notated as an Italian augmented sixth chord Image Tritone substitutions.png thumb center 400px Original, tritone substitution, and augmented sixth chord In a 12 bar blues One of the most common usages of the tritone substitution is in the twelve ... substitution in measure 4 that is, with Gb7 substituted for C7. I IV I bV7 IV IV I I V IV I ... substitution is in ii V I turnaround ii V I progression , which is extremely common in jazz harmony ... more details
Patterns of Force may refer to Patterns of Force Star Trek Patterns of Force Star Trek , an episode of Star Trek Patterns of Force Star Wars novel Patterns of Force Star Wars novel , a Star Wars novel disambig ... more details
Electrophilic substitution reactions are chemical reactions in which an electrophile displaces a group in a compound, typically but not always hydrogen . Electrophilic aromatic substitution is characteristic of aromatic compounds and is an important way of introducing functional groups onto benzene rings. The other main reaction type is electrophilic aliphatic substitution . Electrophilic aromatic substitution main article Electrophilic aromatic substitution In electrophilic substitution in aromatic compounds , an atom appended to the aromatic ring , usually hydrogen, is replaced by an electrophile. The most important reactions of this type that take place are aromatic nitration , aromatic halogenation , aromatic sulfonation and acylation and alkylating Friedel Crafts reaction s. Electrophilic aliphatic substitution In electrophilic substitution in aliphatic compounds, an electrophile displaces a functional group . This reaction is similar to nucleophilic aliphatic substitution where the reactant is a nucleophile rather than an electrophile . The two electrophilic reaction mechanisms, S sub E sub 1 and S sub E sub 2 S ubstitution E lectrophilic , are also similar to the nucleophile counterparts SN1 S sub N sub 1 and SN2 S sub N sub 2 . In the S sub E sub 1 course of action the substrate first ionizes into a carbanion and a positively charged organic residue. The carbanion then quickly recombines with the electrophile . The S sub E sub 2 reaction mechanism has a single transition state in which the old bond and the newly formed bond are both present. Electrophilic aliphatic substitution reactions are Nitrosation Ketone halogenation Keto enol tautomerism aliphatic diazonium coupling carbene insertion into C H bonds See also Nucleophilic substitution References cite book first Jerry last March title Advanced Organic Chemistry edition 5th publisher Wiley year 1985 Category Substitution reactions de Elektrophile Substitution et Elektrofiilne asendusreaktsioon fr Substitution ... more details
Substitution is a fundamental concept in logic . Substitution is a syntax logic syntactic transformation on String computer science strings of symbol formal symbols of a formal language . In propositional logic , a substitution instance of a propositional formula is a second formula obtained by replacing symbols of the original formula by other formulas. For any consistency consistent formal system , any substitution of a tautology logic tautology will also produce a tautology. Definition Where and represent Well formed formula formula s of propositional logic, is a substitution instance of if and only if may be obtained from by substituting formulas for symbols in , always replacing an occurrence of the same symbol by an occurrence of the same formula. For example R imp S & T imp S is a substitution instance of P & Q and A eqv A eqv A eqv A is a substitution instance of A eqv A In some deduction systems for propositional logic, a new expression a proposition may be entered on a line of a derivation if it is a substitution instance of a previous line of the derivation Hunter 1971, p.  118 . This is how new lines are introduced in some axiomatic system s. In systems that use rule of inference rules of transformation , a rule may include the use of a substitution instance ... formula math a math by substitution is said to be a substitution instance of math a math . If math a math is a closed propositional formula we count math a math itself as its only substitution ... is a tautology, and is a substitution instance of , then is again a tautology. This fact implies the soundness of the deduction rule described in the previous section. See also Substitution property ... Rule of universal substitution Lambda calculus Substitution Truth value semantics Unification ... Substitution Logic logic Category Propositional calculus Category Concepts in logic Category Logical truth Category Automated theorem proving Category Logic programming de Substitution Logik ... more details
Font substitution is the process of using one computer font font in place of another when the intended font either is not available or does not contain glyph s for the required Codepoint characters . Font substitution can be aided by classifying fonts into font family generic font families , such that for example a sans serif font is substituted by another sans serif font. font substitutions defined in operating system s font configuration for concrete font names font families , such that for example Arial font is substituted by metric compatible font Liberation Sans or Nimbus Sans L . font substitutions defined in application software s e.g. text processor font configuration for concrete font names. When font substitution is being used to find a replacement for an unavailable character, it can lead to inconsistent visual appearance as part of a word or sentence is displayed in one font and another part is displayed in the substituted font. A method to work around this problem is to display the entire word or paragraph in the substituted font. Nevertheless, font substitution may be critical to scripts not well supported by a large font inventory having the required Unicode range. Examples of systems that perform font substitution include fontconfig , Adobe Reader , Unidrv , Microsoft Word since Word 2002 or OpenOffice.org . Not all systems that claim to offer font substitution are able to substitute for missing characters some are only capable of substituting for missing fonts. Major modern web browser s, are capable of font substitution with the exception of versions of Internet Explorer older than Internet Explorer 7 version 7 . See also Fallback font Web typography External links http library.gnome.org admin system admin guide 2.32 fontconfig 4.html.en Description of font substitution in fontconfig http www.mozilla.org projects intl fonts.html Mozilla on the utility of font switching Category Digital typography Substitution typ stub fr Substitution de police ... more details
unreferenced date January 2010 In algebra , the operation of substitution can be applied in various contexts involving formal objects containing symbols often called variable mathematics variable s or indeterminate variable indeterminate s the operation consists of systematically replacing occurrences of some symbol by a given value. A common case of substitution involves polynomial s, where substitution of a numerical value for the indeterminate of a univariate polynomial amounts to evaluating the polynomial at that value. Indeed this operation occurs so frequently that the notation for polynomials is often adapted to it instead of designating a polynomial by a name like P as one would do for other mathematical objects one could define say math P X X 5 3X 2 5X 17 math so that substitution for X can be designated by replacement inside P X , say math P 2 13 math or math P X 1 X 5 5X 4 10X 3 7X 2 4X 14 math . Substitution can however also applied to other kinds of formal objects built from symbols, for instance elements of free group s. In order for substitution to be defined, one needs an algebraic structure with an appropriate universal property , that asserts the existence of unique homomorphisms that send indeterminates to specific values the substitution then amounts to finding the image under such a homomorphism. Substitution is related to, but not identical to function composition it is also closely related to reduction in lambda calculus . In contrast to these notions however, the accent in algebra is on the preservation of algebraic structure by the substitution operation, the fact that substitution gives a homomorphism for the structure at hand in the case of polynomials, the ring mathematics ring structure . algebra stub Category Algebra ... more details
Unreferenced auto yes date December 2009 Orphan date December 2009 A substitution of attorney is a legal document that may be created during a lawsuit if a party wishes to replace its Lawyer attorney with another one. Both attorneys must sign the document which is otherwise void law void . Category Legal procedure DEFAULTSORT Substitution Of Attorney Law term stub ... more details