Refimprove date December 2009 Primitive in the sense most relevant to phylogenetics means resembling ... phylogenetics basal , and Derived trait derived states, to the likes of primitive and advanced ... DEFAULTSORT PrimitivePhylogenetics Category Evolutionary biology no Utviklingsgrad ..., as more primitive than a beetle, that in its more advanced Morphology biology morphology has all ... under discussion, the term primitive has several meanings, and they are not clearly distinct. Even in the field of Phylogenetics phylogeny it is a difficult concept to deal with unambiguously. Aspects related to ancestry and adaptation In the field of evolution , primitive , when used as a descriptive ... as primitive because they are older in the evolutionary time scale, and are less complex than later ... to regard those ancestors as more primitive than the mayflies at least. Though this might seem obvious ... in the simplest linear terms, the concept primitive is a very relative one. But that is not all ... the silverfish more primitive than the mayfly, just because it does not produce wings and other ... n as anything but primitive, when it is hardly distinguishable from a fossil half a billion years ... features, it is easy to think of that as a notional move away from the primitive state when a population ... derived , rather than a primitive state. Only the more naively moralistic authors made much use of terms such as degeneracy or reversion to more primitive states. For instance the writings of John Langdon ... directly amounted to reversion to the primitive level of primitive human races. ref cite book last ... in terms such as primitive . The word may seem convenient, but it confuses concepts that need separate consideration. Professionals in fields such as phylogenetics prefer to use terms specific to the discipline ... such as primitivity. Evolutionary biology Evolutionary biologists hardly use the term primitive many ... year 1997 isbn 9780198502944 ref The term primitive has been so frequent among popular writings however ... more details
wiktionary primitivePrimitive may refer to Anarcho primitivism , an anarchist critique of the origins and progress of civilization Primitive culture , one that lacks major signs of economic development or modernity Noble savage , uncorrupted by the influences of civilization Primitive communism , a pre agrarian form of communism according to Karl Marx and Friedrich Engels Primitive Church, another name for early Christianity Primitive Baptist , a religious movement seeking to retain or restore early Christian practices Primitivephylogenetics characteristic of an early stage of development or evolution, cf. Basal phylogenetics basal Meteorology Primitive equations , a set of nonlinear differential equations that are used to approximate atmospheric flow Mathematics Simple extension Primitive element field theory Primitive element finite field Primitive cell crystallography Primitive notion , axiomatic systems Primitive polynomial , one of two concepts Primitive function or Antiderivative , F &prime f Primitive group Primitive permutation group Primitive root of unity see Root of unity Definition . Computer science Language primitive , the simplest element provided by a programming language Machine code , instructions and data directly understandable by a CPU Primitive data type , a datatype provided by a programming language Geometric primitive , the simplest kinds of figures in computer graphics Cryptographic primitive s, low level cryptographic algorithms frequently used to build ... 20th century art movement Literature Primitive , a novel by J. F. Gonzalez Primitive , a novel by Mark Nykanen Music Primitive Cyndi Lauper song , by Cyndi Lauper Primitive The Groupies song , by The Groupies and covered by The Cramps The Primitives , a British indie rock band Primitive album , by Soulfly Primitive Neil Diamond album , by Neil Diamond Primitive Radio Gods , an American alternative rock band Primitive , a song by Annie Lennox, from her album Diva Annie Lennox album Diva album ... more details
In phylogenetics , a basal clade is the earliest clade to branch in a larger clade it appears at the base of a cladogram . A basal group forms an Outgroup cladistics outgroup to the rest of the clade, such as in the following example phylogeny Basal group clade Non basal group Non basal group Non basal group Non basal group The word basal is preferred to the term primitive , which may carry false connotations of inferiority or a lack of complexity. The term basal can only be correctly applied to clades of organisms, not to individual traits possessed by the organisms although it can be misused in this manner in technical literature. While the term basal applies to clades, characters or traits are usually considered derived if they are absent in a basal group, but present in other groups. This assumption only holds true if the basal group is a good analogy for the last common ancestor of the group. As an example, the flowering plant family Amborellaceae is considered the most basal Lineage evolution lineage of extant angiosperm s. clade phylogeny Amborellales Clade Monocot s Magnoliid s Eudicot s In animal family Hominidae , the gorillas are an outgroup to chimpanzees, bonobos and humans. These four species form a clade, the subfamily Homininae , of which gorillas are the basal member. clade phylogeny Clade Human s clade Bonobo s Common Chimpanzee Chimpanzee s Gorilla s However, in the family Hominidae, the orangutans form an outgroup to the subfamily Homininae, the clade to which gorillas, chimpanzees, bonobos and humans all belong. clade Orangutan s clade phylogeny Clade Human s clade Bonobo s Common Chimpanzee Chimpanzee s Gorilla s References cite journal title A critical reappraisal of the fossil record of the bilaterian phyla first1 Graham E. last1 Budd first2 S ren last2 Jensen journal Biological Reviews publisher Cambridge University Press volume 75 issue 2 year ... Page publisher Tree of Life web project Category Phylogenetics ca Basal filog nia es Basal eo Baza ... more details
File Heterobranchia tree.png thumb Graph of neighbor joining phylogenetic tree shows a clear split support visualised by long parallel edges for Acochlidiacea in red color . The graph is based on datasets by J rger et al. 2010 ref name J rger 2010 J rger K. M., St ger I., Kano Y., Fukuda H., Knebelsberger T. & Schr dl M. 2010 . On the origin of Acochlidia and other enigmatic euthyneuran gastropods, with implications for the systematics of Heterobranchia . BMC Evolutionary Biology 10 323. doi 10.1186 1471 2148 10 323 . ref and generated by SplitsTree . A split in phylogenetics is a bipartition of a set of taxon taxa , and the smallest unit of information in unrooted phylogenetic tree s each edge of an unrooted phylogenetic tree represents one split, and the tree can be efficiently reconstructed from its set of splits. Moreover, when given several trees, the splits occurring in more than half of these trees give rise to a consensus tree, and the splits occurring in a smaller fraction of the trees generally give rise to a consensus Phylogenetic network Split Network . See also SplitsTree , a program for inferring phylogenetic split networks. References reflist Category Phylogenetics Category Trees data structures ... more details
Molecular phylogenetics IPA en m l kj l r fa l d n t ks pron is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism s evolutionary relationships. The result of a molecular phylogenetics phylogenetic analysis is expressed in a phylogenetic tree . Molecular phylogenetics is one aspect of molecular systematics , a broader term that also includes the use of molecular data in taxonomy and biogeography . History of molecular phylogenetics Further History of molecular evolution The theoretical frameworks for molecular systematics were laid in the 1960s in the works of Emile Zuckerkandl , Emanuel Margoliash , Linus Pauling , and Walter M. Fitch . ref Edna Su rez D az & Victor H. Anaya Mu oz 2008 History, objectivity, and the construction of molecular phylogenies. Stud. Hist. Phil. Biol. & Biomed. Sci. 39 451 468 ref Applications of molecular systematics were pioneered by Charles Sibley Charles G. Sibley bird s , Herbert C. Dessauer herpetology , and Morris Goodman primate s , followed by Allan Wilson Allan C. Wilson , Robert K. Selander , and John C. Avise who studied various groups . Work with protein electrophoresis began around 1956. Although the results were not quantitative and did not initially improve on morphological classification, they provided tantalizing hints that long held notions of the classifications of bird s, for example, needed substantial revision. In the period of 1974 1986, DNA DNA hybridization was the dominant technique. ref Ahlquist, Jon E., 1999 Charles G. Sibley A commentary on 30 years of collaboration ... cite doi 10.1371 journal.pbio.1000602 ref See also Molecular evolution Computational phylogenetics PhyloCode Microbial phylogenetics Phylogenetic nomenclature References MolPhylEvol48 23,48 176,48 ... Systematics and Molecular Phylogenetics http www.ncbi.nlm.nih.gov pmc articles PMC1693355 pdf 15253352.pdf The promise of a DNA taxonomy Mark L. Blaxter phylo Category Phylogenetics Category Molecular ... more details
Computational phylogenetics is the application of computational algorithm s, methods and programs to Phylogenetics ... Sci 113 3353 3354. ref Traditional phylogenetics relies on morphology biology morphological data obtained ... the more recent field of molecular phylogenetics uses nucleotide sequences encoding genes or amino acid sequences encoding protein s as the basis for classification. Many forms of molecular phylogenetics ... phylogenetics can be either rooted or unrooted depending on the input data and the algorithm ... homology Morphological analysis The basic problem in morphological phylogenetics is the assembly of a matrix ... in morphological phylogenetics problems and solutions. Syst Biol 50 5 689 99. ref Because morphological ... hard problems first applied to phylogenetics in the early 1980s. ref name hendy Hendy MD, Penny D. 1982 ... regions. As its name implies, it requires as input both a branching rule in the case of phylogenetics ... to phylogenetics. A simple way of defining the bound is a maximum number of assumed evolutionary ... distribution is a point of contention among users of Bayesian inference phylogenetics methods. ref ... algorithms, although the choice of move set varies selections used in Bayesian phylogenetics include ... a Markov chain Monte Carlo method. Mol Biol Evol 46 409 18. ref The use of Bayesian methods in phylogenetics ... Molecular phylogenetics methods rely on a defined substitution model that encodes a hypothesis about ... annurev.ecolsys.36.102003.152633 title Model Selection in Phylogenetics year 2005 author Sullivan, Jack ... interpretation but penalizes complex models more heavily. ref name Sullivan See also List of phylogenetics software Cladistics PHYLIP Phylogenetic comparative methods Phylogenetic tree Phylogenetics Systematics Microbial phylogenetics Evolutionary dynamics References Reflist Further reading Charles ... Phylogenetics , Oxford University Press, ISBN 9780198509424 Barry A. Cipra 2007 , http siam.org pdf ... Evolution Category Computational phylogenetics ca Filogen tica computacional es Filogen tica computacional ... more details
Microbial phylogenetics is the study of the evolution ary relatedness among various groups of microorganism s. The molecular approach to microbial Molecular phylogenetics phylogenetic analysis , pioneered by Carl Woese in the 1970s and leading to the three domain model Archaea , Bacteria , Eucaryota , revolutionized our thinking about evolution in the microbial world. Phylogenetic analysis plays a central role in microbiology and the emerging fields of comparative genomics and phylogenomics require substantial knowledge and understanding of phylogenetic analysis and computational methods. ref name OrenA cite book author Oren, A Papke, RT editor year 2010 title Molecular Phylogeny of Microorganisms publisher Caister Academic Press isbn 978 1 904455 67 7 ref ref name Blum cite book author Blum, P editor year 2010 title Archaea New Models for Prokaryotic Biology publisher Caister Academic Press isbn 978 1 904455 27 1 ref Historical overview When at the end of the 19th century information began to accumulate about the diversity within the bacteria l world, scientists started to include the bacteria in phylogenetic schemes to explain how life on Earth may have developed. Some of the early phylogenetic tree s of the prokaryote world were morphology based others were based on the then current ideas on the presumed conditions on our planet at the time that life first developed. Around 1950 many leading microbiologists, including Roger Stanier and C. B. van Niel , had become pessimistic with respect to the possibility of ever reconstructing bacterial phylogeny. The concept of the prokaryote eukaryote dichotomy did little to clarify phylogenetic relationships. The developing technology ... The purpose of Molecular phylogenetics phylogenetic analysis is to understand the past evolutionary ... taxonomy Computational phylogenetics History of molecular evolution Molecular phylogeneticsPhylogenetics ... Microbial phylogenetics Category Phylogenetics ... more details
Orphan date April 2010 Lead too long date February 2010 Phylogenetics of mimicry Mimicry is well understood and heavily studied within specific mimicry groups, individually referred to as mimicry complexes . However the evolutionary and phylogenetic relationships between mimic model or co mimicry pairs are less apparent. The difficulty many researchers face in trying to build phylogenies for mimicry complexes is trying to discriminate between analogous traits, shared characteristics developed through convergent evolution, and homologous traits, shared characteristics that are due to a shared common ancestor. In some instances it is clear whether some traits are analogous or homologous, as in mimicry complexes involving completely unrelated organisms or those of different Order biology orders . In other cases involving similar or same species mimics with different phenotypes , the explanation for trait evolution becomes less clear. To build phylogenies for these groups of mimics, scientists would first need to understand which species is the mimic and which is the model, then afterwards determine how evolution will have proceeded to increase the instances of the shared characteristics. ref Ruxton, G. D., T. N. Sherrat, and M. P. Steed. 2004. Avoiding attack the evolutionary ecology of crypsis, warning signals, & mimicry. Oxford Biology. ref In M llerian mimicry , defended species have evolved similar appearances as a means to share the cost of predator learning M ller, 1862 . The classic example of M llerian mimicry is the Heliconius butterfly. There are 54 species of this unpalatable butterfly with over 700 names applied to its various phenotypes Brower, 1996 . It functions as a perfect M llerian mimic because all species of the Heliconius are inedible and form symbiotic relationships. Extensive research on Heliconius butterflies has even shown not just phenotypic similarities, but also behavioral commonalities within an overlapping territory. ref Mallet, J. and L. E ... more details
Infobox journal title Molecular Phylogenetics and Evolution cover File Molecular Phylogenetics and Evolution.gif editor D.E. Wildman discipline Phylogeny , evolutionary biology formernames abbreviation Mol. Phylogenet. Evol. publisher Academic Press country United States frequency 12 year history 1992&ndash present openaccess license impact 3.871 impact year 2008 website http www.sciencedirect.com science journal 10557903 link1 link1 name link2 link2 name RSS atom JSTOR OCLC LCCN CODEN ISSN 1055 7903 eISSN Molecular Phylogenetics and Evolution is a peer review ed scientific journal of evolutionary biology and phylogenetics . The journal is edited by D.E. Wildman . Indexing The journal is indexed in EMBiology Journal Citation Reports Scopus Web of Science External links Official website http www.elsevier.com wps find journaldescription.cws home 622921 description description Category Elsevier academic journals Category Evolutionary biology journals Category Phylogenetics Category Molecular biology Category Publications established in 1992 ... more details
In mathematics , a primitive root may mean either a primitive root modulo n in modular arithmetic , or a primitive nth root of unity amongst the solutions of x sup n sup 1 in a field mathematics field See also primitive element disambiguation mathdab ... more details
Future Primitive may refer to Future Primitive band , from Southern California Future Primitive and Other Essays , a collection of essays by anarchist John Zerzan Future Primitive The New Ecotopias , a short story collection edited by Kim Stanley Robinson Future Primitive album Future Primitive album , the fifth album by Australian rock band The Vines A skateboarding video by Powell Peralta Filmography Powell Peralta disambig ... more details
In mathematics, the term primitive element can mean Primitive root modulo n Primitive root modulo n , in number theory Primitive element field theory , an element that generates a given field extension Primitive element finite field , an element that generates the multiplicative group of a finite field in a Hopf algebra , an element X on which the comultiplication has the value X X 1 1 X in a free group , an element of a free generating set See also primitive root disambiguation mathdab ... more details
Primitive man may refer to Primitive culture Primitive Man album , a 1982 album by the Australian synthpop band Icehouse The Mind of Primitive Man , a 1911 anthropology work by Franz Boas A Primitive Man s Career to Civilization , a 1912 UK film directed and written by Cherry Kearton See also Primitive disambiguation Prehistoric man Caveman Human evolution Homo genus archaic Homo sapiens Primitivism disambig ... more details
disambig In different branches of mathematics , primitive polynomial has different meanings In field theory mathematics field theory , a primitive polynomial field theory primitive polynomial is the minimal polynomial field theory minimal polynomial of a primitive element finite field primitive element of the finite field finite extension field GF p sup m sup . In algebra and specifically ring theory , a Primitive polynomial ring theory primitive polynomial is a polynomial over an integral domain R such as the integer s such that no non invertible element of R divides all its coefficient s at once. ru zh ... more details
Distinguish primary ideal In mathematics , a left primitive ideal in ring theory is the Annihilator ring theory annihilator of a simple module simple left module mathematics module . A right primitive ideal is defined similarly. Note that despite the name left and right primitive ideals are always two sided ideals. The quotient of a ring by a left primitive ideal is a left primitive ring . References Citation last1 Isaacs first1 I. Martin title Algebra publisher Brooks Cole Publishing Company isbn 0 534 19002 2 year 1994 Category Ideals Category Module theory Abstract algebra stub bg ... more details
Infobox Embryology Name PAGENAME Latin GraySubject GrayPage Image Gray14.png Caption Surface view of embryo of Hylobates concolor. The amnion has been opened to expose the embryonic disk. Primitive pit not labeled, but region is visible. Image2 Caption2 System CarnegieStage Days Precursor GivesRiseTo MeshName MeshNumber DorlandsPre DorlandsSuf The primitive pit is a depression in the center of the primitive node , connecting to the notochord . It consists of part of the primitive streak . External links http www.embryology.ch anglais hdisqueembry triderm01.html http isc.temple.edu marino embryology EMBII97 img020.GIF http cancerweb.ncl.ac.uk cgi bin omd?primitive pit http embryology.med.unsw.edu.au Medicine BGDlab3 11.htm http www.ana.ed.ac.uk database humat notes embryo ectoderm primstr.htm Gray s Anatomy stub Embryology Category Developmental biology ... more details
Primitive skills refers to prehistoric handicrafts and pre industrial technology. Primitive skills are those skills that relate to living off the land, often using handcrafted tools made from naturally gathered materials. Examples of primitive skills include Hunter gatherer gathering and foraging native plants and animals for food, skinning and preparing game, basketry and pottery pot making, constructing shelters, fire making , and useful Field guide plant identification . Interest in primitive skills has coincided with a resurgence in interest in natural and self sufficient living techniques. In North America, primitive skills enthusiasts often emulate Indigenous peoples of the Americas Native American traditional crafts. In Europe, primitive skills enthusiasts often practice traditional Bronze Age Bronze and Iron Age art forms. ref Cite web title Society of Primitive Technology About url http www.primitive.org About SPT.htm date 2009 accessdate 19 September 2009 ref See also div col colwidth 30em Anarcho primitivism Flintknapper List of plants with edible leaves Off the grid Survivalism Self sufficiency div col end References references External links http www.primitiveskills.org Earthskills Rendezvous Non profit organization that hosts several primitive skills events gatherings. http www.woodlandsurvival.com Pine Home Primitive Skills, Outdoor Safety and Wilderness Survival Instructional site with pics,skills instructions, knife reviews, forum discussing primitive skills, outdoor events and gatherings. http www.mapsgroup.org Midatlantic Primitive Skills Group Non profit organization that hosts several primitive skills events gatherings as well as classes in the lithic arts, trapping, tracking and more. Prehistoric technology Culture stub Category Survival skills ... more details
In mathematics , logic , and formal system s, a primitive notion is an undefined concept. In particular, a primitive notion is not defined in terms of previously defined concepts, but is only motivated informally, usually by an appeal to Intuition knowledge intuition and everyday experience. In an axiomatic theory or other formal system , the role of a primitive notion is analogous to that of axiom . In axiomatic theories, the primitive notions are sometimes said to be defined by one or more axioms, but this can be misleading. Formal theories cannot dispense with primitive notions, under pain of infinite regress . Alfred Tarski explained the role of primitive notions as follows When we set out to construct a given discipline, we distinguish, first of all, a certain small group of expressions ... we call PRIMITIVE TERMS or UNDEFINED TERMS, and we employ them without explaining their meanings. At the same ... consideration, unless its meaning has first been determined with the help of primitive terms and of such expressions ... the fundamental concept of set is an example of a primitive notion. As Mary Tiles wrote The definition ... of a primitive, undefined, term. As evidence, she quotes Felix Hausdorff A set is formed by the grouping ... an axiomatic system begins with its axiom s, the primitive notions may not be explicitly stated. Susan Haak 1978 wrote, A set of axioms is sometimes said to give an implicit definition of its primitive terms. Examples . In Naive set theory , the empty set is a primitive notion. To assert that it exists would be an implicit axiom . Peano arithmetic , the successor function and the number zero are primitive notions. Axiomatic system Axiomatic systems , the primitive notions will depend upon the set ... the primitive notions are point, line, plane, congruence, betweeness and incidence . Euclidean geometry , under Giuseppe Peano Peano s axiom system the primitive notions are point, segment and motion ... Tiles 2004 The Philosophy of Set Theory , page 99 DEFAULTSORT Primitive Notion Category Mathematical ... more details
Unreferenced date October 2008 Image Ruralroad.jpg thumb right A primitive road near Dayton, Washington , United States United States of America A primitive road is a minor road system, used for travel or transportation that is generally not maintained or paved. Classification A primitive road can be classified if it meets the following criteria. In the United States most of these roads are maintained by the local township. Is not classified as part of the county primary road system, Has a gravel or earth driving surface and Has an average annual daily traffic of one hundred or fewer vehicles. See also County road References reflist External links http apps.leg.wa.gov RCW default.aspx?cite 36.75.300 Definition of Primitive Road from the state of Washington. Road types Category Types of roads ... more details
This list of phylogenetics software is a compilation of computational phylogenetics software used to produce phylogenetic tree s. Such tools are commonly used in comparative genomics , cladistics , and bioinformatics . Methods for estimating phylogenies include neighbor joining , maximum parsimony also simply referred to as parsimony , UPGMA , Bayesian inference in phylogeny Bayesian phylogenetic inference , maximum likelihood and Distance matrices in phylogeny distance matrix methods . class wikitable Name Description Methods Link Author BAli Phy Simultaneous Bayesian inference of alignment and phylogeny Bayesian inference, alignment as well as tree search. http www.biomath.ucla.edu msuchard bali phy homepage M.A. Suchard, B. D. Redelings BATWING Bayesian Analysis of Trees With Internal Node Generation Bayesian inference, demographic history, population splits http www.mas.ncl.ac.uk nijw download I. J. Wilson, Weale, D.Balding BayesPhylogenies Bayesian inference of trees using Markov Chain Monte Carlo methods Bayesian inference, multiple models, mixture model auto partitioning http www.evolution.rdg.ac.uk BayesPhy.html download M. Pagel, A. Meade BayesTraits Analyses trait evolution among groups of species for which a phylogeny or sample of phylogenies is available Trait analysis http www.evolution.rdg.ac.uk BayesTraits.html download M. Pagel, A. Meade BEAST Bayesian Evolutionary Analysis Sampling Trees Bayesian inference, relaxed molecular clock, demographic history http beast.bio.ed.ac.uk ... L.S. Vinh, A. von Haeseler LisBeth Three item analysis for phylogenetics and biogeography Three ... download Thomas Keane MOLPHY Molecular phylogenetics protein or nucleotide Maximum likelihood ... uk.html Institut Pasteur phylogeny webservers http www.expasy.org tools phylo ExPASy List of phylogenetics ... koloko softlinks list of evolutionary genetics software DEFAULTSORT List Of Phylogenetics Software Category Bioinformatics Category Computational phylogenetics Category Lists of software Phylogenetics ... more details
Other uses Modern Primitives disambiguation Original research date May 2009 Globalize date May 2009 File Moderm primitive in nature 2.JPG thumb Female modern primitive 1993 Modern primitives or urban primitives are people in developed nations who engage in body modification rituals and practices while making reference or homage to the rite of passage practices in primitive cultures ref http news.nationalgeographic.com news 2004 12 1210 041210 tattoos 2.html National Geographic Ancient and Modern Tattoos Celebrated in Photography Book ref These practices may include body piercing , tattooing , play piercing , flesh hook suspension body modification suspension , corset training , scarification , branding persons branding , and Self harm cutting . The motivation for engaging in these varied practices may be personal growth, rite of passage , or spirituality spiritual or sexual curiosity. Roland Loomis, also known as Fakir Musafar , is considered the father of the modern primitive movement. ref http gauntlet.ucalgary.ca story 5541 Gauntlet decorating the Modern Primitive ref The 1989 RE Search book Modern Primitives book Modern Primitives is largely responsible Clarify date May 2009 for the promotion of the concept of modern primitivism. References Reflist Cite book last Vale first V. authorlink V. Vale coauthors Andrea Juno title Modern Primitives book Modern Primitives publisher RE Search year 1989 pages url isbn 978 0 940642 14 0 External links dmoz Society Subcultures Urban Primitive Urban Primitive commons category Modern primitives DEFAULTSORT Modern Primitive Category Body modification Category Cultural appropriation Category Sexuality and gender identity based cultures Bodymodification stub de Modern Primitive no Moderne primitive ... more details
In the branch of abstract algebra known as ring theory , a left primitive ring is a Ring mathematics ... R is said to be a left primitive ring if and only if it has a faithful module faithful simple module simple module mathematics left R module . A right primitive ring is defined similarly with right R modules. There are rings which are primitive on one side but not on the other. The first example was constructed ... the distinction can be found in harv Rowen 1988, p.159 An internal characterization of left primitive rings is as follows a ring is left primitive if and only if there is a maximal left ideal containing no nonzero twosided ideal ring theory ideal . The analogous definition for right primitive rings is also valid. The structure of left primitive rings is completely determined by the Jacobson density theorem A ring is left primitive if and only if it is isomorphic to a Jacobson density theorem ... a division ring. Another equivalent definition states that a ring is left primitive if and only if it is a prime ... June 2011 . Properties One sided primitive rings are both semiprimitive ring s and prime ring s. Since the ring product of two or more nonzero rings is not prime, it is clear that the product of primitive rings is never primitive. For a left Artinian ring , it is known that the conditions left primitive , right primitive , prime , and simple ring simple are all equivalent, and in this case it is a semisimple ... ring with a minimal one sided ideal, left primitive right primitive prime . A commutative ring is left primitive if and only if it is a field mathematics field . Being left primitive is a Morita equivalence Morita invariant property . Examples Every simple ring R with unity is both left and right primitive. However, a simple non unital ring, may not be primitive. This follows from the fact that maximal .... Weyl algebra s over fields with characteristic algebra characteristic zero are primitive, and since ... positive char? Full linear rings A special case of primitive rings is that of full linear rings . A left ... more details
Used predominantly in geometry , solid state physics , and mineralogy , particularly in describing crystal structure , a primitive cell is a minimum cell corresponding to a single lattice point of a structure with translational symmetry in 2 dimensions, 3 dimensions, or other dimensions. A lattice can be characterized by the geometry of its primitive cell. The primitive cell is a fundamental domain with respect to translational symmetry only. In the case of additional symmetries a fundamental domain is smaller. A crystal can be categorized by its lattice and the atoms that lie in a primitive cell the basis . A cell will fill all the lattice space without leaving gaps by repetition of crystal translation operations. Primitive translation vectors are used to define a crystal translation vector, math vec T math , and also gives a lattice cell of smallest volume for a particular lattice. The lattice and translation vectors math vec a 1 math , math vec a 2 math , and math vec a 3 math are primitive if the atoms look the same from any lattice points using integers math u 1 math , math u 2 math , and math u 3 math . math vec T u 1 vec a 1 u 2 vec a 2 u 3 vec a 3 math The primitive cell is defined by the primitive axes vectors math vec a 1 math , math vec a 2 math , and math vec a 3 math . The volume, math V c math , of the primitive cell is given by the parallelepiped from the above axes as, math V c vec a 1 cdot vec a 2 times vec a 3 . , math Category Condensed matter physics Category Crystallography Category Mineralogy ... more details
Infobox Embryology Name PAGENAME Latin nodus primitivus GraySubject 6 GrayPage 47 Image Caption Image2 Caption2 System CarnegieStage Days 17 Precursor GivesRiseTo MeshName MeshNumber DorlandsPre k 04 DorlandsSuf 12471954 The primitive knot or primitive node is the organizer for gastrulation in vertebrates. Diversity In bird s it is known as Hensen s node , and is named after its discoverer Victor Hensen . In amphibian s, it is known as Spemann s organizer , and is named after Hans Spemann who, with Mangold, first identified the organizer in 1924. ref name pmid17563072 cite journal author Garcia Fern ndez J, D Aniello S, Escriv H title Organizing chordates with an organizer journal Bioessays volume 29 issue 7 pages 619 24 year 2007 pmid 17563072 doi 10.1002 bies.20596 ref Development The primitive knot starts as a regional knot of cells that forms on the blastodisc immediately anterior to where the outer layer of cells will begin to migrate inwards an area known as the primitive streak . Posterior to the node is the primitive pit, where the cells of the epiblast the upper layer of embryonic cells initially begin to invaginate. This invagination expands posteriorly into the primitive groove as the cells layers continue to move into the space between the embryonic cells and the yolk. This differentiates the embryo into the germ layer s endoderm, mesoderm, and ectoderm. The primitive knot migrates posteriorly as gastrulation proceeds, eventually being absorbed into the tail bud. The Default Model The cells of the primitive node secrete many cellular signals essential for neural differentiation. After gastrulation the developing embryo is divided into ectoderm, mesoderm, and endoderm. The ectoderm gives rise to epithelial and neural tissue, with neural tissue being the default cell fate. Bone morphogenetic proteins BMPs suppress neural differentiation and promote epithelial growth. Therefore, the primitive node the dorsal lip of the blastopore secretes BMP antagonists, ... more details
Infobox album See Wikipedia WikiProject Albums Name Primitive World Type Album Artist Littl ans Cover Littlans Primitive World.JPG Released July 2, 2008 Recorded July 2007 Genre Indie music Indie , Rock music Rock Length Label Revtone USA br Vital UK br Vinyl Junkie Japan Producer Reviews Last album This album Primitive World br 2008 Next album Misc Singles Name Primitive World Type studio Single 1 Is It Wrong? Single 1 date May 9, 2008 Primitive World is the debut album by indie rock band Littl ans . The album was recorded in July 2007 and mastered at Sterling Sound in New York . The album was released in Japan on 2 July 2008 and in the UK on 1 December 2008. Track listing Don t Call It Love Is It Wrong? Everytime Primitive World Did You Hide from Saturday Night? End Dead Chelsea Our Way While on Your Way Back to Me Here Comes the Night Japanese Bonus Tracks Aftermath Stay Alive Aweful All The Day Category Littl ans albums Category 2008 debut albums ... more details
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