Otheruses Commute disambiguation Expert subject multiple Neuroscience Mathematics date February 2009 In neurophysiology , commutation is the process of how the brain s Biological neural network neural circuits exhibit non commutativity . Physiologist Douglas B. Tweed and coworkers consider whether certain neural circuits in the brain exhibit noncommutativity and state blockquote In noncommutative algebra , order makes a difference to multiplication, so that math a times b neq b times a math . This feature is necessary for computing rotation rotary motion, because order makes a difference to the combined effect of two rotations. It has therefore been proposed that there are non commutative operators in the brain circuits that deal with rotations, including motor system circuits that steer the human eye eye s, head anatomy head and limbs, and sensory system circuits that handle spatial information. This idea is controversial studies of eye and head control have revealed behaviours that are consistent with non commutativity in the brain, but none that clearly rules out all commutative models. blockquote Tweed goes on to demonstrate non commutative computation in the vestibulo ocular reflex by showing that subjects rotated in darkness can hold their gaze points stable in space correctly computing different final eye position commands when put through the same two rotations in different orders, in a way that is unattainable by any commutative system. ref Douglas B. Tweed and others, Nature journal Nature 399, 261 263 20 May 1999 ref References Reflist Category Neurophysiology neuroscience stub ... more details
Neurophysiology from Ancient Greek Greek lang grc , neuron , nerve , physis , nature, origin and , wikt logia logia is a part of physiology . Neurophysiology is the study of nervous system function. The primary tools of basic neurophysiological research include electrophysiology electrophysiological recordings such as patch clamp and calcium imaging , as well as some of the common tools of molecular biology . Neurophysiology is connected with electrophysiology, neurobiology , psychology , neurology , clinical neurophysiology , neuroanatomy , cognitive science , biophysics , mathematical biology , and other brain sciences. ref http books.google.com books?id k99lQusj53sC&pg PT27&dq what is Neurophysiology&lr &ei cSIUS665C6WOMquZrbsL v onepage&q &f false The Clinical Neurophysiology Primer By Andrew S. Blum, Seward B. Rutkove, Humana Press, 2007, ISBN 089603996X, 9780896039964 ref History unreferenced section date May 2012 Neurophysiology has been a subject of study since as early as 4,000 B.C. In the early B.C. years, most studies were of different natural sedatives like alcohol and poppy plants. In 1700 B.C., the Edwin Smith surgical papyrus was written. This papyrus was crucial in understanding how the ancient Egyptians understood the nervous system. This papyrus looked at different case studies about injuries to different parts of the body, most notably the head. Beginning around 460 B.C., Hippocrates began to study epilepsy, and theorized that it had its origins in the brain. Hippocrates also theorized that the brain was involved in sensation, and that it was where intelligence was derived from. Hippocrates, as well as most ancient Greeks, believed that relaxation ... neurophysiology patient, had his brain pierced by an iron tamping rod in a blasting accident ... in neurophysiology before 1849, these developments were significant to the study of the brain and body ... earlysciencelab body brainpages brain.html . Category Neurophysiology ar bn ... more details
for the journal Clinical Neurophysiology journal Clinical neurophysiology is a medicine medical specialty ... systems. Examinations in the clinical neurophysiology field are not limited to tests conducted in a laboratory ... neurophysiology is used to mainly help diagnose diseases rather than treat them. In some countries ... clinical neurophysiology departments. Usually these tend to be larger hospitals that are able to employ more specialized staff units. In hospitals that posses clinical neurophysiology facilities ... neurophysiology in the United States The pathway to becoming a clinical neurophysiologist in the US ... to enter a fellowship in Clinical Neurophysiology. Programs may expose their fellows to the broad ... or EMG. Clinical Neurophysiology fellowships are generally 1 2 years in duration and may lead to board certification in one or more subspecialty areas. Where and what takes place in the clinical neurophysiology department? Hospitals that have neurologists and neurosurgeons tend to house clinical neurophysiology ... United Neurodiagnostic Professionals of America http www.neurophys.com Clinical Neurophysiology http www.abpn.com cnp.htm Initial Qualification in the Subspecialty of Clinical Neurophysiology ... del Servicio de Neurofisiolog a Cl nica Organizations for clinical neurophysiology http www.ifcn.info International Federation of Clinical Neurophysiology http www.acns.org American Academy of Clinical Neurophysiology http www.bscn.org.uk British Society for Clinical Neurophysiology http www.nevrofysiologi.no Norwegian Society for Clinical Neurophysiology http www.nvknf.nl Dutch Society for Clinical Neurophysiology http www.neurofisiologia.net Italian Society for Clinical Neurophysiology http www.smnfc.com Mexican Society for Clinical Neurophysiology http www.neurofisiologia.org Sociedad Espa ola ... Czech Society for Clinical Neurophysiology Medicine Neuroscience Nervous system physiology Category Neurophysiology da Neurofysiologi es Neurofisiolog a cl nica no Klinisk nevrofysiologi sv Neurofysiologi ... more details
Infobox journal title Journal of Neurophysiology cover editor David Linden discipline Neuroscience abbreviation J. Neurophysiol. publisher American Physiological Society country United States frequency Monthly history 1938 present openaccess After one year impact 3.114 impact year 2010 website http jn.physiology.org link1 http jn.physiology.org content current link1 name Online access link2 http jn.physiology.org content link2 name Online archive JSTOR OCLC 01695642 LCCN 41016569 CODEN JONEA4 ISSN 0022 3077 eISSN 1522 1598 Portal Neuroscience The Journal of Neurophysiology is a monthly Peer review peer reviewed scientific journal established in 1938. It is published by the American Physiological Society with David Linden as its editor in chief . It publishes original research reports concerning the physiology physiological aspects of neuroscience , along with a small number of literature review review articles and editorial s. All articles published after 1997 are made Open access freely available online one year after publication some special articles become freely available immediately. External links Official http jn.physiology.org Category Publications established in 1938 Category Neuroscience journals Category Bimonthly journals Category English language journals Science journal stub fr Journal of Neurophysiology ... more details
the electrical properties of neurons. His main contributions to neurophysiology involved the study ... Neurophysiology year 2000 publisher W.B. Saunders Company location New York ref Temporal summation ... title Neurophysiology year 1996 publisher Arnold location London ref Mechanism Neurotransmitters ... in Accessory Optic System Neurons journal Journal of Neurophysiology date 24 year 2004 month november ... Shunting Length constant Long Term Potentiation Neurotransmission DEFAULTSORT Summation Neurophysiology Category Neurophysiology ... more details
Orphan date February 2009 The commutation cell is the basic structure in power electronics . It is composed of an electronic switch today a high power semiconductor , not a mechanical switch and a diode ... popular. The purpose of the commutation cell is to chop DC power into square wave alternating current .... By controlling the on and off times the duty cycle of the switch in the commutation cell, the output ... or from an inductor to another should be avoided, as it results in important losses. A Commutation ... the commutation. As the total inductance after the commutation is 2L, the current becomes math frac I 2 math see figure 2 . The energy before the commutation is math frac 1 2 L cdot I 2 math . After ... during the commutation. As a result, it can be seen that a commutation cell can only connect a voltage ... a converter if it uses an inductor to transfer energy. The structure of a commutation cell image Commutation cell practical theroretical.svg thumb 350px Fig. 3 A commutation cell connects two sources ... applications. This makes the commutation cell unidirectional. A bidirectional commutation cell can be obtained by paralleling two unidirectional ones. As told above, a commutation cell must ..., as it is impossible to left it in an open circuit. The basic schematic of a commutation cell is therefore ... to have a perfect synchronization between the switches. At one point during the commutation, they would ... commutation device, i.e its state is controlled by the circuit itself. It will turn on or off at the exact moment it has to. The consequence of using a diode in a commutation cell is that it makes it unidirectional ... unidirectional cells connected in parallel. The commutation cell in converters image Commutation cell in converters.svg thumb left 250px Fig. 4 The commutation cell is present in every switching power supply The commutation cell can be found in any Power electronics power electronic converter. Some ... is always connected between the middle point and one of the external connections of the commutation ... more details
Globalize USA date December 2010 Commutation of sentence involves the reduction of sentence law legal penalties , especially in terms of prison imprisonment . Unlike a pardon , a commutation does not nullify the conviction and is often conditional. Clemency is a similar term, meaning the lessening of the penalty of the crime without forgiving the crime itself. The act of clemency is a reprieve. Today, pardons and reprieves are granted in many countries when individuals have demonstrated that they have fulfilled their debt to society, or are otherwise deserving in the opinion of the pardoning official of a pardon or reprieve. United States In the United States , reduction of a sentence is handled by an Executive government executive head of government and is normally linked to prison ers good behavior. ref Legal Explanations http www.legal explanations.com definitions commutation.htm Commutation Retrieved on April 21, 2007 ref The President of the United States solely holds the power to commute Federal government of the United States federal sentences ref Article II, Section 2 of the United States Constitution http www.law.cornell.edu constitution constitution.articleii.html section2 Power to grant reprieves and pardons for offenses against the United States Retrieved on July 9, 2007 ref while commutations of state charges are handled by the Govenor United States governor s office. ref U.S. Department of Justice http www.usdoj.gov pardon commutation instructions.htm Commutation Instructions Retrieved on July 3, 2007 ref Other countries Around the world, countries accord their head ... US Department of Justice pardon and commutation statistics by presidential administration 1945 2001 http www.usdoj.gov pardon commutation instructions.htm US Department of Justice instructions for submitting a commutation of sentence http www.nytimes.com aponline washington AP CIA Leak Trial.html ... before he left office. DEFAULTSORT Commutation Of Sentence Category Clemency Category Criminal law ... more details
In mathematics , especially in linear algebra and matrix theory , the commutation matrix is used for transforming the vectorized form of a matrix mathematics matrix into the vectorized form of its transpose . Specifically, the commutation matrix K sup m,n sup is the mn mn matrix which, for any m n matrix A , transforms vec A into vec A sup T sup K sup m,n sup vec A vec A sup T sup . Here vec A is the mn 1 column vector obtain by stacking the columns of A on top of one another vec A A sub 1,1 sub , ..., A sub m,1 sub , A sub 1,2 sub , ..., A sub m,2 sub , ..., A sub 1,n sub , ..., A sub m,n sub sup T sup where A A sub i,j sub . The main use of the commutation matrix, and the source of its name, is to commute the Kronecker product for every m n matrix A and every r q matrix B , K sup r,m sup A math otimes math B K sup n,q sup B math otimes math A . References Jan R. Magnus and Heinz Neudecker 1988 , Matrix Differential Calculus with Applications in Statistics and Econometrics , Wiley. Category Linear algebra Category Matrices Linear algebra stub sl Komutacijska matrika ... more details
unreferenced date September 2008 The Commutation Act of 1784, enacted by the British Parliament , reduced the tax on tea from 119 to 12.5 , effectively ending the smuggling trade. William Pitt the Younger , acting on the advice of Richard Twining of the Twinings Tea Company, introduced the Act to increase revenues through legitimate sales of tea by ending 100 years of punitive tea taxes which promoted smuggling. The Act was created to stimulate trade in China for the British East India Company , which at the time was suffering from mounting debts. Indian opium was exchanged for tea in China which was then shipped to Britain for sale on the domestic market. The Commutation Act improved trade relations between Britain and one of its primary tea suppliers, China. UK legislation Category History of tea Category Smuggling Category Great Britain Acts of Parliament 1784 Category Taxation in the United Kingdom UK hist stub ... more details
In mathematics , a commutation theorem explicitly identifies the commutant of a specific von Neumann algebra acting on a Hilbert space in the presence of a Von Neumann algebra Weights, states, and traces trace . The first such result was proved by F.J. Murray and John von Neumann in the 1930s and applies to the von Neumann algebra generated by a discrete group or by the dynamical system associated with a ergodic theory measurable transformation preserving a probability measure . Another important application is in the theory of unitary representation s of Haar measure unimodular locally compact group s, where the theory has been applied to the regular representation and other closely related representations. In particular this framework led to an abstract version of the Plancherel theorem for unimodular ... Tomita Takesaki theory was developed, heralding a new era in the theory of von Neumann algebras. Commutation ... JMJ subseteq M prime. math The commutation theorem of Murray and von Neumann states that border ... . Examples One of the simplest cases of the commutation theorem, where it can easily be seen directly ... and the commutation theorem implies that math lambda Gamma prime prime rho Gamma prime, , , rho Gamma ... 2002 ref Commutation theorem for semifinite traces Let M be a von Neumann algebra and M sub sub the set ... of H satisfying J sup 2 sup I. The commutation theorem of Murray and von Neumann border 1 cellspacing ... algebras can be used to deduce the commutation theorems of Murray and von Neumann equally well the main results on Hilbert algebras can also be deduced directly from the commutation theorems for traces ... commutation theorems for semifinite weights in Tomita Takesaki theory they can be dispensed ... ax, , , rho a x xa. math These actions extend continuously to actions on H . In this case the commutation ... s with x bounded x and y commute for x , y bounded. The commutation theorem follows immediately ... 540 42914 X year 2002 DEFAULTSORT Commutation Theorem Category Von Neumann algebras Category Representation ... more details
In physics , the canonical commutation relation is the relation between canonical conjugate quantities quantities which are related by definition such that one is the Fourier transform of another , for example math x,p x i hbar math between the position x and momentum p sub x sub in the x direction of a point particle in one dimension, where math x,p x xp x p xx math is the commutator of x and p sub x sub , i is the imaginary unit , and is the reduced Planck s constant h 2&pi . This relation is attributed to Max Born , and it was noted by E. Kennard 1927 to imply the Werner Heisenberg Heisenberg uncertainty principle . Relation to classical mechanics By contrast, in classical physics , all observables commute and the commutator would be zero. However, an analogous relation exists, which is obtained by replacing the commutator with the Poisson bracket multiplied by i math x,p 1 , . math This observation led Paul Dirac Dirac to propose that the quantum counterparts math hat f, hat g math of classical observables f , g satisfy math hat f, hat g i hbar widehat f,g , . math In 1946, Hip Groenewold demonstrated that a general systematic correspondence between quantum commutators and Poisson ... . Representations The group mathematics group associated with these commutation relations, x ... the above canonical commutation relations cannot both be bounded operator bounded try taking the trace linear algebra trace of both sides of the relations. The canonical commutation relations can ... exp it x . The uniqueness of the canonical commutation relations between position and momentum is then guaranteed ... L partial x i . math The canonical commutation relations then amount to math x i, pi j i hbar delta ... not satisfy the canonical commutation relations only the canonical momentum does that. This can be seen ... left p frac qA c right , math which has the commutation relations math K i,K j i hbar epsilon ij .... All such nontrivial commutation relations for pairs of operators lead to corresponding uncertainty ... more details
nofootnotes date September 2008 Infobox UK legislation short title Tithe Commutation Act 1836 parliament Parliament of Great Britain long title statute book chapter 6 & 7 Will 4 c 71 introduced by territorial extent royal assent 13 August 1836 commencement repeal date amendments related legislation repealing legislation status Amended original text activeTextDocId legislation history The Tithe Commutation Act of 1836 6 & 7 Will 4 c 71 was an Act of Parliament Act of the Parliament of the United Kingdom with the long title An Act for the Commutation of Tithes in England and Wales . It replaced the ancient system of payment of tithe s in kind with monetary payments. It is especially noted for the maps which were produced as a side effect of the valuation process which the change entailed. Tithe payments Tithes were originally paid as one tenth of the produce of the land crops, eggs, cattle, timber, fishing, etc. to the rector as alms and for payment for his services. The tithes were often stored in a tithe barn attached to the parish. After the dissolution of the monasteries some of the land in question, having passed out of church ownership, had tithes paid to private landlords. Enclosure acts made further modifications in the pattern, either by abolishing tithe payments entirely or replacing them with monetary payments. Various other arrangements also replaced payment in kind, though not systematically. By the time of the Act there was considerable discontent over payment of tithes, most notably in the form of the Tithe War of 1831 1836 in Ireland . Provisions of the act The act substituted a variable monetary payment referred to as the corn rent for any existing tithe in kind. This payment was originally calculated on the basis of a seven year average price of wheat, barley, and oats, with each grain contributing an equal part to the total. Prices were determined nationally ... 2007 05 08 cite web url http www.llgc.org.uk index.php?id 551 title The Tithe Commutation Act 1836 publisher ... more details
Semiotics In semiotics , the commutation test is used to analyze a signifying system. The test identifies signifiers as well as their signifieds, value Semiotics value and significance. The commutation test This test is a metalingual subjective system for analysing textual or other material. It has evolved from a limited method for investigating the structure of individual signs per Roman Jakobson . Its primary uses are to identify distinctive signifiers, define their significance, and divide material into paradigmatic classes and identify the codes to which the signifiers belong Roland Barthes . The initial assumption is that the communication to be analysed represents both a cognitive use of the sign system and a statement that refers to the values of the addresser. The purpose of the test is therefore to illuminate the addresser s intention in using the code in this particular way. It works through a process of substitution, assessing the extent to which a change in the signifier leads to a change in the signified. The first step, therefore, is to exclude one signifier from the material to be analysed. This is a test of redundancy to identify what meaning is lost if any by omitting that sign. It will be relatively unusual to find that one sign is completely superfluous, but more common to find that the contribution of the one sign to the whole meaning is relatively weak. The weakness or strength of its contribution can be calibrated more exactly by placing alternate synonymous and antonymous signs in the context. This will enable the analyst to make a judgement on the distinctiveness of the particular signifier chosen by the author artist and of its value to the meaning, i.e. as more or less necessary for maintaining the meaning and or rule structure in different occurrences ... of the original signifier. According to Daniel Chandler, the commutation test may involve any of four ... DEFAULTSORT Commutation Test Semiotics Category Semiotics ... more details
Wiktionarypar commute commutation commutative commutativity Commute , commutation or commutative may refer to Commuting , the process of travelling between a place of residence and a place of work Commutative property , a property of a mathematical operation whose result is insensitive to the order of its arguments Equivariant map , a function whose composition with another function has the commutative property Commutative diagram , a graphical description of commuting compositions of arrows in a mathematical category Commutative semigroup , commutative monoid , abelian group , and commutative ring , algebraic structures with the commutative property Commuting matrices , sets of matrices whose products do not depend on the order of multiplication Commutation of sentence , a reduction in severity of punishment Commutationneurophysiology , how certain neural circuits in the brain exhibit noncommutativity Tonggeun , a class of train in Korea which translates to Commuter Commutation, a synonym for Packet switching switching in computer networking and telecommunications Commutation, the action of applying currents or voltages to the proper electrical motor phases so as to produce optimum motor torque at a motor s shaft. See Commutator electric . Commutation, where a member of a pension scheme gives up part or their entire pension in exchange for an immediate lump sum payment. It is also known as a cash option. disambig cs Komutace de Kommutation fr Commutation ... more details
In mathematics, Hilbert algebras occur in the theory of von Neumann algebras in Commutation theorem Tomita Takesaki theory Mathdab Category Von Neumann algebras ... more details
wiktionary shunting Shunting is a concept in neurophysiology. Shunting may also refer to Ribosome shunting , a mechanism in protein biosynthesis Shunting rail , a rail transport operation See also Shunt disambiguation disambig ... more details
Summation may refer to Summation , a mathematical notation Evaluating sums , evaluation of sums in closed form Summation Neurophysiology , a way of achieving action potential in a neuron In law, another name for the closing argument disambig ... more details
Semiotics In semiotics , syntagmatic analysis is Semantic analysis linguistics analysis of syntax or surface structure syntagmatic structure as opposed to paradigm s paradigmatic analysis . This is often achieved using Commutation test semiotics commutation test s http www.aber.ac.uk media Documents S4B sem04.html . Syntagmatic means one element selects the other element either to precede it or to follow it. For example, the the definitive article the selects a noun and not a verb. ling stub Category Semiotics bg sv Syntagmatisk analys ... more details
In linguistics , a syntagma is an elementary constituent segment within a text. Such a segment can be a phoneme , a word , a grammatical phrase , a sentence linguistics sentence , or an event within a larger narrative structure, depending on the level of analysis. Syntagmatic analysis involves the study of relationships rules of combination among syntagmas. At the lexical level, syntagmatic structure in a language is the combination of words according to the rules of syntax for that language. For example English uses determiner adjective noun, e.g. the big house . Another language might use determiner noun adjective Spanish lang es la casa grande and therefore have a different syntagmatic structure. At a higher level, narrative structures feature a realistic temporal flow guided by tension and relaxation thus, for example, events or rhetorical figures may be treated as syntagmas of epic structures. Syntagmatic structure is often contrasted with paradigmatic structure. In semiotics , syntagmatic analysis is semantic analysis linguistics analysis of syntax or surface structure syntagmatic structure , rather than paradigm s as in paradigmatic analysis . Analysis is often achieved through commutation test semiotics commutation test s. ref http www.aber.ac.uk media Documents S4B sem04.html ref See also Syntax Syntagmatic analysis Paradigmatic analysis Saussure Semiotics commutation test semiotics Commutation test Source Middleton, Richard 1990 2002 . Studying Popular Music. Philadelphia Open University Press. ISBN 0 335 15275 9. Cubitt, Sean 1984 . Cited in Middleton 2002 . References reflist Category Narratology Category Linguistics de Syntagma pl Syntagma ru ... more details
Unreferenced date November 2007 Orphan date November 2006 The sucrose gap technique is used to create a Nerve conduction study conduction block in a nerve . A high concentration of sucrose is applied to a length of nerve, which prevents the correct opening and closing of Sodium channel sodium and potassium channel s. neuroscience stub Category Medical tests Category Neurophysiology ... more details
Orphan date November 2006 Context date October 2009 An oblique dendrite is a dendrite that branches from the main dendritic tree. References http www.jneurosci.org cgi content full 16 9 2983 Dailey ME and Smith SJ, The Dynamics of Dendritic Structure in Developing Hippocampal Slices . J Neurosci 16 9 , 1996 pp. 2983 2994. Category Neurophysiology neuroscience stub ... more details
orphan date September 2009 Electromyoneurography is the combined use of electromyography and electroneuronography ref Spiegel MB. Electromyoneurography. Am Fam Physician 1978 Nov 18 5 119 30. ref References reflist Category Electrodiagnosis Category Electrophysiology Category Neurophysiology Category Neurotechnology Category Neurology procedures Neuroscience stub ... more details
orphan date May 2010 Unreferenced date December 2009 Hair Plexuses or Root Hair Plexuses are special groups of nerve fiber endings. Each forms a network around a hair follicle and is a Receptor biochemistry receptor it sends nervous impulses to the brain when the hair moves. Category Neurophysiology neuroanatomy stub ... more details
John Rothwell may refer to John Rothwell physiologist , professor of neurophysiology John Rothwell hurler born 1951 , Irish retired hurler Arthur Uther Pendragon John Timothy Rothwell, born 1954 , English eco campaigner, neo druid leader, media personality, and self declared reincarnation of King Arthur hndis Rothwell, John ... more details
Merge Farm revenue commutation date March 2011 A Revenue Farm is a franchise with a license to collect state revenue, with a monopoly right to practice a certain business. Such a monopoly was granted by the state government to a Farmer for a limited period of time in a strictly defined location in a city, district or province. In return, the farmers bidders had to pay the government in advance to be guaranteed monopoly status. ref Ngo, Tak Wing. 1999 1999 . Hong Kong s History State and Society Under Colonial Rule. United Kingdom Routledge. ISBN 0415203058. ref See also Farm revenue commutation References reflist Category National accounts Category Article Feedback 5 econ stub ... more details
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