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 , mathematical biology biophysical neurophysiology , ethology , neuroanatomy , cognitive science 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 See also Brain Neuroscience Neural coding Neurology References reflist Neuroscience Psychiatry Nervous system physiology neuroscience stub Category Neurophysiology ar bn bg cs Neurofyziologie de Neurophysiologie es Neurofisiolog a eu Neurofisiologia fr Neurophysiologie id Neurofisiologi it Neurofisiologia he lt Neurofiziologija nl Neurofysiologie pl Neurofizjologia ro Neuropsihologie ru sr vi Sinh l h c th n kinh zh ... more details
Clinical neurophysiology is a medicine medical speciality that studies the central and peripheral nervous systems through the recording of bioelectrical activity, whether spontaneous or stimulated. In some countries it is a part of neurology or psychiatry , for example the United States http www.abpn.com cnp.htm and Germany . In others it is an autonomous speciality, such as Spain , Portugal , Italy , the United Kingdom , Finland , Sweden and Norway . Its main parts are Electromyography and nerve conduction study acronyms include EMG, NCS Electroencephalography acronyms include EEG Evoked potential s acronyms include EP, SSEP, TCeMEP, TCmMEP Polysomnography , an overnight test which finds sleep abnormalities Intraoperative monitoring , Neuromonitoring Intraoperative neurophysiologic monitoring , surgical neurophsyiology acronyms include IOM and IONM. External links http www.aan.com American Academy of Neurology http www.neurophys.com Clinical Neurophysiology http www.abpn.com cnp.htm Initial Qualification in the Subspecialty of Clinical Neurophysiology , from the American Board of Psychiatry and Neurology http www.neuro.wustl.edu neuromuscular Neuromuscular disease center, Washington University School of Medicine, St. Louis, MO http www.clevelandclinicmeded.com medicalpubs diseasemanagement ... 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 de Neurofisiolog a Cl nica http ... Neurophysiology es Neurofisiolog a cl nica no Klinisk nevrofysiologi ... more details
Italic title 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 impact year website http jn.physiology.org link1 http www.jn.physiology.org contents by date.0.shtml link1 name Online archive link2 link2 name RSS atom JSTOR OCLC LCCN CODEN ISSN 0022 3077 eISSN 1522 1598 Portal Neuroscience The Journal of Neurophysiology is a Peer review peer reviewed scientific journal founded in 1938. It is published by the American Physiological Society on a monthly basis, edited by David Linden . It publishes original research reports concerning the physiological aspects of neuroscience , along with a small number of literature review review article s and editorial s. All articles published after 1997 are made Open access publishing freely available online one year after publication some special articles become freely available immediately. External links http jn.physiology.org Journal of Neurophysiology website Category Publications established in 1938 Category Neuroscience journals journal stub fr Journal of Neurophysiology ... 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 Criminal law Criminal law stub ... 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
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. math stub Category Linear algebra Category Matrices 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 Acts of the Parliament of Great Britain Category History of tea Category Smuggling Category 1784 in Great Britain Category 1784 in law 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 brackets could not hold consistently. However, he did appreciate that such a systematic correspondence ... commutation relations cannot both be bounded operator bounded . The canonical commutation relations ... of the canonical commutation relations between position and momentum is guaranteed by the Stone von Neumann theorem . The group mathematics group associated with the commutation relations is called ... L partial x i math . The canonical commutation relations then amount to math x i, pi j i hbar delta ... 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 ... such nontrivial commutation relations for pairs of operators lead to corresponding uncertainty principle ... 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. IV, 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. IV, 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 ... more details
Semiotics In semiotics , the commutation test is used to identify the value Semiotics value or significance of any of the signifiers used in the material to be analysed. Discussion The first stage of development in semiotics related to the spoken and or written form of language . Later, it was expanded to cover all sign semiotics sign systems that have an information al content. As Umberto Eco says, A sign is everything which can be taken as significantly substituting for something else. 1976 Semiotics studies the relationship between the form of the sign the signifier and the Meaning semiotics meaning expressed the signified , and thereby attempts to reveal the process of communicating understanding . In each case, a message is to be sent by an addresser to an addressee. For this to occur, the addresser and addressee must use a common code semiotics code , Hence, language evolves dynamically. The community will identify a lexical semiotics lexical thing that needs to be referred to in their language. By common agreement, a sign sometimes called a signal will be selected. Of the many possible shades of meanings that it can be used to convey, one or more will be selected and encoded , i.e. the chosen meaning s will be denotation semiotics denoted or associated with the sign within the broader framework of syntactic and semantic systems available within the community. When the audience is exposed to the sign, the expectation is that they will be able to decode the meaning. As Roman Jakobson adds, there will also be an emotion al element or value Semiotics value which represents the addresser s attitude psychology attitude towards the thing . This will either become a connotation .... The commutation test This test is a metalingual subjective system for analysing textual or other ... the contribution of the original signifier. According to Daniel Chandler, the commutation test ... 1976 Original English version of Trattato di semiotica generale, 1975 DEFAULTSORT Commutation Test ... more details
Wiktionarypar commute commutation Commute or commutation may refer to Commuting , the process of travelling between a place of residence and a place of work Commutativity , a property of a mathematical operation 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
Orphan date November 2007 A Bioamplifier is a device used to gather and increase the signal integrity of human neurophysiology neurophysiologic electrical activity for output to various sources. See also Neurophysiology neuroscience stub Category Neurophysiology science stub ru ... 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
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 disambig ... more details
The compound muscle action potential or compound motor action potential is a electromyography investigation electrical study of muscle function . med stub Category Neurophysiology ... 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
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 sv Syntagmatisk analys ... 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 Neuroscience stub ... more details
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