Nucleotidediversity is a concept in molecular genetics which is used to measure the degree of polymorphism biology polymorphism within a population. ref cite journal title Mathematical Model for Studying Genetic Variation in Terms of Restriction Endonucleases journal PNAS date October 1, 1979 first last coauthors Masatoshi Nei and Wen Hsiung Li volume 76 issue 10 pages 5269 73 pmid 291943 pmc 413122 url doi 10.1073 pnas.76.10.5269 author Nei, M. ref One commonly used measure of nucleotidediversity was first introduced by Nei and Li in 1979. This measure is defined as the average number of nucleotide differences per site between any two DNA sequences chosen randomly from the sample population, and is denoted by . It is given by the formula math pi sum ij x i x j pi ij 2 sum i 1 n sum j 1 ... and j th sequences, sub ij sub is the number of nucleotide differences per nucleotide site between the i th and j th sequences, and n is the number of sequences in the sample. Nucleotidediversity ... species, ref cite journal title Molecular diversity at 18 loci in 321 wild and 92 domesticate lines reveal no reduction of nucleotidediversity during Triticum monococcum Einkorn domestication implications ... relationships. ref cite journal title Nucleotidediversity in gorillas journal Genetics ... cgi pmidlookup?view long&pmid 15082556 author Yu, N. ref Nucleotidediversity can be calculated ... Amplified Polymorphic DNA RAPD data ref cite journal title Estimating nucleotidediversity from ... Length Polymorphism AFLP data. ref cite journal title A method for estimating nucleotidediversity ... of nucleotidediversity and a variety of other statistical tests for intra population and inter ... Reflist DEFAULTSORT NucleotideDiversity Category Molecular genetics genetics stub ar ... diversity, and is similar to expected heterozygosity. This statistic may be used to monitor diversity ... DnaSP &mdash DNA Sequence Polymorphism, is a software package for the analysis of nucleotide polymorphism ... more details
FMN , and NADP NADP sup sup . Nucleotide derivatives such as the nucleoside triphosphate s play central ... Nucleotide structure File Ribose structure 2.png thumb Ribose structure indicating numbering of carbon atoms A nucleotide is composed of a nucleobase nitrogenous base , a five carbon sugar ... carbon site most common. Cyclic nucleotide s form when the phosphate group is bound to two of the sugar ... either a purine or a pyrimidine base. Nucleic acid s are polymeric macromolecules made from nucleotide ..., nucleotides can be synthesized de novo synthesis de novo or recycled through nucleotide salvage ... nucleotide pool in mouse tissues and tumors in vivo journal volume issue pages publisher location date url doi id accessdate ref The components used in de novo nucleotide synthesis are derived ... last Jones first ME authorlink coauthors title Pyrimidine nucleotide biosynthesis in animals Genes ... proceeds by a 10 step pathway to the branch point intermediate Inosine monophosphate IMP , the nucleotide ... reaction unique to purine nucleotide biosynthesis , PPAT catalyzes the displacement of PRPP s pyrophosphate ... forming 5 phosphorybosylamine 5 PRA and establishing the anomeric form of the future nucleotide ... NH sub 3 sub donor . Length unit Nucleotide abbreviated nt is a common length unit for single stranded ... http users.ox.ac.uk linc1775 blueprint.htm IUPAC nucleotide code ref Apart from the five A, G, C, T U ... . These nucleotide codes are listed here. class wikitable IUPAC nucleotide code Base Adenine A Adenine ... explanation of nucleotide structure Genetics state uncollapsed Nucleobases, nucleosides, and nucleotides ... Nukleotida is Kirni it Nucleotide he jv Nukleotida ka kk ht Nikleyotid la Nucleotidum lb Nukleotid lt Nukleotidas hu Nukleotid mk ms Nukleotida nl Nucleotide ... simple Nucleotide sk Nukleotid sl Nukleotid sr sh Nukleotidi fi Nukleotidi sv Nukleotid th tr N kleotit uk ur vi Nucleotide zh ... more details
wiktionary diversity wikiquote Science and technology Biodiversity , the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Diversity Index , a statistic intended to assess the diversity of any population in which each member belongs to a unique group, type or species. Diversity scheme , a method for improving the reliability of a message signal by using multiple communications channels. Antenna diversity , a method of wireless communication that use two or more antennas to improve the quality and reliability of the link. Sociology, economics, law, and politics Multiculturalism , or ethnic diversity, the promotion of multiple ethnic cultures Cultural diversity , the respect of difference cultures and interculturality Diversity business , the business tactic which encourages diversity to better serve a heterogeneous customer base Diversity politics , the political and social policy of encouraging tolerance for people of different backgrounds Diversity jurisdiction , a concept under which U.S. federal courts can hear suits between parties from different states Diversification finance involves spreading investments Diversification marketing strategy is a corporate strategy to decrease market penetration Team composition Other Diversity dance troupe , an English dance troupe who won the third series of Britain s Got Talent Diversity training , the process of educating employees, students or volunteers to function in a diverse environment disambiguation ar bg da Diversitet de Diversit t it Diversit nl Diversiteit ja pt Diversidade tr e itlilik ... more details
enzyme Name nucleotide diphosphokinase EC number 2.7.6.4 CAS number 53167 92 3 IUBMB EC number 2 7 6 4 GO code 0050148 image width caption In enzymology , a nucleotide diphosphokinase EC number 2.7.6.4 is an enzyme that catalysis catalyzes the chemical reaction ATP nucleoside 5 phosphate math rightleftharpoons math AMP 5 phosphonucleoside 3 diphosphate Thus, the two substrate biochemistry substrates of this enzyme are adenosine triphosphate ATP and nucleoside 5 phosphate , whereas its two product chemistry products are adenosine monophosphate AMP and 5 phosphonucleoside 3 diphosphate . This enzyme belongs to the family of transferase s, specifically those transferring two phosphorus containing groups diphosphotransferase s . The systematic name of this enzyme class is ATP nucleoside 5 phosphate diphosphotransferase . Other names in common use include nucleotide pyrophosphokinase , ATP nucleotide pyrophosphotransferase , ATP nucleotide 3 pyrophosphokinase , and nucleotide 3 pyrophosphokinase . References reflist 1 cite journal author Murao S and Nishino T date 1974 title Isolation and identification of ATP nucleotide pyrophosphotransferase producing microorganism journal Agric. Biol. Chem. volume 38 pages 2483&ndash 2489 doi 10.1271 bbb1961.38.2483 issue 12 cite journal author Nishino T and Murao S date 1974 title Purification and some properties of ATP nucleotide pyrophosphotransferase of Streptomyces adephospholyticus journal Agric. Biol. Chem. volume 38 pages 2491&ndash 2496 doi 10.1271 bbb1961.38.2491 issue 12 cite journal author Nishino T and Murao S date 1975 title Characterization of pyrophosphoryl transfer reaction of ATP nucleotide pyrophosphotransferase journal Agric. Biol. Chem. volume 39 pages 1007&ndash 1014 doi 10.1271 bbb1961.39.1007 issue 5 enzyme stub Category EC 2.7.6 Category Enzymes of unknown structure ... more details
Image Cyclic adenosine monophosphate 2D skeletal.png thumb Cyclic adenosine monophosphate Image CGMP.png thumb Cyclic guanosine monophosphate A cyclic nucleotide is any nucleotide in which the phosphate group is bonded to two of the sugar s hydroxyl groups, forming a cyclical or ring structure. These include cyclic AMP cyclic GMP cyclic ADP ribose These function as second messenger s associated with G protein s and calcium signaling . External links MeshName Nucleotides, Cyclic Nucleobases, nucleosides, and nucleotides Category Nucleotides Biochem stub bg et Ts klilised nukleotiidid nl Cyclisch nucleotide no Syklisk nukleotid sr Cikli ni nukleotid ... more details
Nucleotide sugars are the activated forms of monosaccharides . Nucleotide sugars act as glycosyl donors in glycosylation reactions. Those reactions are catalyzed by a group of enzymes called glycosyltransferase s. History The anabolism of oligosaccharides and, hence, the role of nucleotide sugars was not clear until 1950s when Leloir and his coworkers found that the key enzymes in this process are the glycosyltranserases. These enzymes transfer a glycosyl group from a sugar nucleotide to an acceptor. ref cite journal author Derek Horton title The Development of Carbohydrate Chemistry and Biology journal Carbohydrate Chemistry, Biology and Medical Applications pages 1 28 year 2008 doi 10.1016 B978 0 08 054816 6.00001 X isbn 9780080548166 ref Biological Importance To act as glycosyl donors, those monosaccharides should exist in a highly energetic form. This occurs as a result of a reaction between nucleoside triphosphate NTP and glycosyl monophosphate phosphate at anomeric carbon . Image activatedmonosaccahride.png frameless center 600px Activation of Monosaccharides Types There are nine sugar nucleotides in complex animals which act as glycosyl donors and they can be classified depending on the type of the nucleoside forming them ref http www.cshlpress.com default.tpl?action full& eqskudatarq ... Diphosphate GDP mannose GDP Man , GDP Fuc. Cytosine Monophosphate CMP Neu5Ac , it is the only nucleotide sugar in the form of nucleotide monophosphate. In plants and bacteria many other sugars are used ... in nucleotide sugar precursor synthesis and O antigen assembly journal Carbohydr. Res. volume 338 ... of some nucleotide sugars example from each type . class wikitable border 1 style text align center ... GDP Man Relationship between glycosylation pathways and different diseases Normal metabolism of nucleotide ... feeding problems. See also Nucleotide sugars metabolism Carbohydrate chemistry Glycosyltransferase References reflist External links MeshName Nucleotide sugars Nucleotide sugars Category Metabolism Category ... more details
enzyme Name nucleotide diphosphatase EC number 3.6.1.9 CAS number 9032 64 8 IUBMB EC number 3 6 1 9 GO code 0004551 image width caption In enzymology , a nucleotide diphosphatase EC number 3.6.1.9 is an enzyme that catalysis catalyzes the chemical reaction a dinucleotide H sub 2 sub O math rightleftharpoons math 2 mononucleotides Thus, the two substrate biochemistry substrates of this enzyme are dinucleotide and water H sub 2 sub O , whereas its product chemistry product is Nucleotide mononucleotide . This enzyme belongs to the family of hydrolase s, specifically those acting on acid anhydrides in phosphorus containing anhydrides. The systematic name of this enzyme class is dinucleotide nucleotidohydrolase . Other names in common use include nucleotide pyrophosphatase , and nucleotide sugar pyrophosphatase . This enzyme participates in 5 metabolism metabolic pathways purine metabolism , starch and sucrose metabolism , riboflavin metabolism , nicotinate and nicotinamide metabolism , and pantothenate and coa biosynthesis . Structural studies As of 2007 alt As of late 2007 , 5 tertiary structure structures have been solved for this class of enzymes, with Protein Data Bank PDB accession codes PDB link 1NQY , PDB link 1NQZ , PDB link 2GSN , PDB link 2GSO , and PDB link 2GSU . References reflist 1 cite journal author Jacobson JB and Kaplan NO date 1957 title A reduced pyridine nucleotide pyrophosphatase journal J. Biol. Chem. volume 226 pages 427&ndash 437 pmid 13428775 cite journal author Kornberg A and Pricer WE date 1950 title Nucleotide pyrophosphatase journal J. Biol. Chem. volume 182 pages 763&ndash 778 cite journal author Kumar SA, Rao NA, Vaidyanathan CS date 1965 title Nucleotidases in plants. I. Partial purification and properties of the enzyme hydrolyzing flavine adenine dinucleotide from mung bean seedlings Phaseolus radiatus journal Arch. Biochem. Biophys. volume ... MN, Kaplan NO and Lamborg MF date 1958 title A heat activated diphosphopyridine nucleotide pyrophosphatase ... more details
A salvage pathway is a Metabolic pathway pathway in which nucleotide s purine and pyrimidine are synthesized from intermediates in the degradative pathway for nucleotides. Salvage pathways are used to recover bases and nucleosides that are formed during biodegradation degradation of RNA and DNA . This is important in some organs because some tissues cannot undergo de novo synthesis . The salvaged bases and nucleosides can then be converted back into nucleotides. Substrates The salvage pathway requires distinct substrates Pyrimidines Uridine phosphorylase adds ribose 1 phosphate to the free base uracil, forming uridine monophosphate. Uridine kinase then phosphorylates this nucleoside into its diphosphate and triphosphate forms. Deoxythymidine phosphorylase adds deoxyribose 1 phosphate to thymine, forming deoxythymidine monophosphate. Thymidine kinase can then phosphorylate this compound to deoxythymidine diphosphate and triphosphate. Image Pyrimidine Ribonucleotide Salvage.png thumb none 400px The salvage of pyrimidine ribonucleotides. Purines Phosphoribosyltransferases add activated ribose 5 phosphate called phosphoribosyl pyrophosphate or PRPP to bases, creating nucleotide monophosphates. There are two types of phosphoribosyltransferases adenine phosphoribosyltransferase APRT and hypoxanthine guanine phosphoribosyltransferase HGPRT . Lesch Nyhan syndrome is associated with a deficiency of HGPRT. class wikitable Nucleoside Enzyme Nucleotide hypoxanthine hypoxanthine guanine phosphoribosyl transferase HGPRT Inosine monophosphate IMP guanine hypoxanthine guanine phosphoribosyl transferase HGPRT Guanosine monophosphate GMP adenine adenine phosphoribosyltransferase APRT Adenosine monophosphate AMP External links http www.chem.brandeis.edu pochapsky research.html Enzymes in the methionine salvage pathway structure and function at Brandeis University Category Genetics genetics stub Protein metabolism Nucleotide metabolism ca Salvament de nucle tids de Salvage Pathway ja ... more details
Unreferenced date November 2006 Image Aminoallyl Uridine.svg right frame The structure of aminoallyluridine Aminoallyl nucleotides are used in post labeling of nucleic acid s to be used in microarray s. These nucleotides are formally known as 5 3 amino allyl nucleotides since the aminoallyl group is usually attached to carbon 5 of the pyrimidine ring of uracil and cytosine . They are usually abbreviated as aa , such as aa dUTP. The amine group in the aminoallyl moiety is aliphatic and thus more reactive compared to the amine groups that are directly attached to the rings aromatic of the bases. Uses The aminoallyl group in aminoallyl modified nucleotides is reactive with dyes such as the cyanine series, AnaSpec HiLyte Fluor , or Alexa Fluor dyes that also been modified to be amine reactive. A problem with this method is that the dyes react with the buffering agent usually used for storage of nucleotides. Instead a carbonate buffer is used. The DNA or RNA from a sample is copied in vitro by T7 polymerase, RT polymerase or some other polymerase except of eukaryotic origin in a mix of nucleotides in which one, typically uracil RNA and also DNA , is a mix aminoallyl NTP and normal UTP. An alternative method is using thiol reactive dyes. DEFAULTSORT Aminoallyl Nucleotide Category Nucleic acids Category Nucleotides molecular cell biology stub ... more details
orphan date February 2010 N nucleotides , or nontemplated nucleotides are believed to exist only to create diversity at V D J junctions see V D J recombination during lymphocyte development ref name NCBI http www.ncbi.nlm.nih.gov pmc articles PMC390357 http www.ncbi.nlm.nih.gov pmc articles PMC390357 ref . The addition of these nucleotides is aided by an enzyme called Terminal deoxynucleotidyl transferase TdT References reflist Category Nucleotides ... more details
Image Junctionaldiversity1.PNG frame right Generation of junctional diversity through recombination illustrated between two gene segments D blue and J green . Sections highlighted in red show nucleotides added at each stage. Junctional diversity describes the DNA sequence variations introduced by the improper joining of gene segments during the process of V D J recombination . This process of V D J recombination has vital roles for the vertebrate immune system as it is able to generate a huge repertoire of different T cell receptor TCR and immunoglobulin molecules required for pathogen antigen recognition by T cells and B cells respectively. The inaccuracies of joining provided by junctional diversity is estimated to triple the diversity initially generated by these V D J recombinations. Citation needed date September 2009 Process Junctional diversity concludes the process of somatic recombination or V D J recombination , during which the different variable gene segments those segments involved in antigen recognition of TCRs and immunoglobulins are rearranged and unused segments removed. This introduces DNA repair Double strand breaks double strand breaks between the required segments. These ends form hairpin loops and must be joined together to form a single strand summarised in diagram, right . This joining is a very inaccurate process which results in the variable addition or subtraction of nucleotide s and thus generates junctional diversity. ref name Janeway2005 cite book author Janeway, C.A., Travers, P., Walport, M., Shlomchik, M.J. year 2005 title Immunology edition 6th publisher Garland Science ref Generation of junctional diversity starts as the proteins, recombination activating gene 1 and 2 RAG1 and RAG2 , along with DNA repair proteins, such as DCLRE1C Artemis ... 2 pmc 2676214 ref Junctional diversity is liable to cause frame shift mutation s and thus production ... Janeway2005 References reflist 1 Immune system DEFAULTSORT Junctional Diversity Category Immune system ... more details
Functional diversity is a politically and socially correct term for special needs , disability , impairment and handicap , which began to be used in Spain in scientific writing, at the initiative of those directly affected, in 2005. ref cite paper title Functional diversity, a new term in the struggle for dignity in the diversity of the human being author Javier Roma ach and Manuel Lobato work Independent Living Forum Spain &mdash May 2005 format PDF url http www.leeds.ac.uk disability studies archiveuk zavier Functional 20Diversity 20 20 20 20 20 20 20 20 20 20 fv 20Roma F1ach.pdf ref This term is intended to replace other ones with pejorative semantics. It proposes a shift towards non negative, non disparaging and non patronizing terms. The formal justification of the term can be found in the book El Modelo de la Diversidad by Agustina Palacios and Javier Roma ach, 2007, ISBN 978 84 964 7440. Examples of usage people with functional diversity instead of people with special needs physical functional diversity mobility functional diversity , person who uses a wheelchair , wheelchair user motor functional diversity dexterity functional diversity visual functional diversity , people who use screen readers as their primary means of accessing a computer people with a visual processing functional diversity auditory functional diversity mental functional diversity intellectual functional diversity cognitive functional diversity organic functional diversity circumstantial and or temporary functional diversity person with a functional diversity persons without functional diversity rather than normal or healthy people without functional diversity , typically developing children References reflist Further reading cite journal journal Disabil Rehabil. date 2007 Oct 30&ndash Nov 15 volume 29 issue 20&ndash 21 pages 1625&ndash 1633 title Constructive Functional Diversity a new paradigm beyond disability and impairment. author Patston P. pmid 17896220 doi 10.1080 09638280701618778 ... more details
In wireless communications, diversity gain is the increase in signal to interference ratio due to some diversity scheme , or how much the transmission power can be reduced when a diversity scheme is introduced, without a performance loss. Diversity gain is usually expressed in decibel , and sometimes as a power ratio. An example is soft handoff gain. For selection combining N signals are received, and the strongest signal is selected. When the N signals are independent and Rayleigh distributed, the expected diversity gain has been shown to be math sum k 1 N frac 1 k math , expressed as a power ratio. ref D.G. Brennan, Linear diversity combining techniques, Proc. IRE , vol.47, no.1, pp.1075 1102, June 1959 ref See also Array gain Diversity combining References references Category radio resource management Wireless stub ... more details
The term gamma diversitydiversity was introduced by R. H. Whittaker ref name Whittaker1960 Whittaker ..., 279 338. ref together with the terms alpha diversitydiversity and beta diversitydiversity . Whittaker s idea was that the total species diversity in a landscape is determined by two different things, the mean species diversity in sites or habitats at a more local scale and the differentiation among those habitats . According to this reasoning, alpha diversity and beta diversity constitute independent components of gamma diversity math gamma alpha times beta math Scale considerations ... has been reached on what spatial scales are appropriate to quantify gamma diversity. ref Whittaker ... diversity. Journal of Biogeography 28 453 470. DOI 10.1046 j.1365 2699.2001.00563.x ref It has therefore been proposed that the definition of gamma diversity does not need to be tied to a specific spatial scale, but gamma diversity can be measured for an existing dataset at any scale of interest. ref name Tuomisto2010a Tuomisto, H. 2010 A diversity of beta diversities straightening up a concept gone awry. Part 1. Defining beta diversity as a function of alpha and gamma diversity. Ecography ..., it needs to be taken into account that the species diversity in the dataset generally gives an underestimation of the species diversity in a larger area. The smaller the available sample in relation .... 2010 A diversity of beta diversities straightening up a concept gone awry. Part 2. Quantifying beta diversity and related phenomena. Ecography, 33, 23 45. doi 10.1111 j.1600 0587.2009.06148.x ref The degree of underestimation can be estimated from a species area curve . Different gamma diversity concepts Researchers have used different ways to define species diversitydiversity , which in practice has led to different definitions of gamma diversity as well. Often researchers use the values given by one or more Diversity index diversity indices , such as species richness , the Shannon index or the Simpson ... more details
Unreferenced stub auto yes date December 2009 Transmit diversity is radio communication using signals that originate from two or more independent sources that have been modulation modulated with identical information bearing signals and that may vary in their transmission characteristic s at any given instant. It can help overcome the effects of fading , outages, and Electronic circuit circuit failures. When using diversity transmission and reception, the amount of received signal improvement depends on the independence of the fading characteristics of the signal as well as circuit outages and failures. See also Antenna diversityDiversity gain Diversity scheme Dynamic Single Frequency Networks DSFN Macro diversity Multiple input multiple output communications MIMO Single frequency networks SFN Space time block coding based transmit diversity STTD Soft handover DEFAULTSORT Transmit Diversity Category Radio resource management Wireless stub ... more details
Unreferenced date December 2008 Notability Notability date December 2008 Diversity coding is a particular technique for antenna diversity and is implemented by Space time code space time coding . Category Radio resource management wireless stub ... more details
configured for space diversity In telecommunications , a diversity scheme refers to a method for improving ... channels with different characteristics. Diversity plays an important role in combatting fading and co .... Diversity techniques may exploit the multipath propagation , resulting in a diversity gain , often measured in decibels . The following classes of diversity schemes can be identified Time diversity .... Frequency diversity The signal is transmitted using several frequency channels or spread over ... or DS CDMA . Space diversity The signal is transmitted over several different propagation paths. In the case ... of wireless transmission, it can be achieved by antenna diversity using multiple transmitter antennas transmit diversity and or multiple receiving antennas reception diversity . In the latter case, a diversity ... macrodiversity or site diversity . If the antennas are at a distance in the order of one ... diversity Multiple versions of a signal are transmitted and received via antennas with different polarization. A diversity combining technique is applied on the receiver side. Multiuser diversity Multiuser diversity is obtained by opportunistic user scheduling at either the transmitter or the receiver ... quality information to the transmitter with the limited level of resolution. Cooperative diversity Achieves antenna diversity gain by using the cooperation of distributed antennas belonging to each node. See also Space time coding STC Antenna diversity Macrodiversity Diversity combining Aperture synthesis Cooperative diversity Channel access method Fresnel zone Tropospheric scatter External links http www.radioblvd.com DiversityDD1.html Diversity reception Background information of the development of Diversity reception devices. http www.antenna theory.com arrays diversity.php Antenna Diversity Tutorial www.Antenna Theory.com K. T. Wong http www.eie.polyu.edu.hk enktwong & A. K. Y. Lai ... diversity 2 in mobile handsets technologies , see Christian Le Floc h, Regis Duval,Gerard ... more details
The term alpha diversitydiversity was introduced by R. H. Whittaker ref name Whittaker1960 Whittaker ... Diversity. Taxon, 21, 213 251. doi 10.2307 1218190 ref together with the terms beta diversitydiversity and gamma diversitydiversity . Whittaker s idea was that the total species diversity in a landscape gamma diversity is determined by two different things, the mean species diversity in sites or habitats at a more local scale alpha diversity and the differentiation among those habitats beta diversity . Scale considerations Both the area or landscape of interest and the sites or habitat s within ... Scale spatial spatial scales are appropriate to quantify alpha diversity. ref Whittaker, R. J. et al. 2001 . Scale and species richness towards a general, hierarchical theory of species diversity ... been proposed that the definition of alpha diversity does not need to be tied to a specific spatial scale alpha diversity can be measured for an existing dataset that consists of subunits at any scale. ref name Tuomisto2010a Tuomisto, H. 2010 A diversity of beta diversities straightening up a concept gone awry. Part 1. Defining beta diversity as a function of alpha and gamma diversity. Ecography, 33 ... to be taken into account that the species diversity in the subunits generally gives an underestimation of the species diversity in larger areas. ref Colwell, R. K. and Coddington, J. A. 1994 Estimating ..., 345, 101 118. ref ref Tuomisto, H. 2010 A diversity of beta diversities straightening up a concept gone awry. Part 2. Quantifying beta diversity and related phenomena. Ecography, 33, 23 45. doi 10.1111 j.1600 0587.2009.06148.x ref Different alpha diversity concepts Ecologists have used several slightly different definitions of alpha diversity. Whittaker himself used the term both for the species diversity in a single subunit and for the mean species diversity in a collection of subunits. ref name Whittaker1960 ref name Whittaker1972 It has been argued that defining alpha diversity as a mean ... more details
The term beta diversitydiversity was introduced by R. H. Whittaker ref name Whittaker1960 Whittaker ..., 279 338. ref together with the terms alpha diversitydiversity and gamma diversitydiversity . The idea was that the total species diversity in a landscape is determined by two different things, the mean species diversity at the habitat level and the differentiation among habitats . Whittaker ... have invented more. As a result, the definition of beta diversity has become quite contentious. ref name Tuomisto2010a Tuomisto, H. 2010 A diversity of beta diversities straightening up a concept gone awry. Part 1. Defining beta diversity as a function of alpha and gamma diversity. Ecography 33 2 22. doi 10.1111 j.1600 0587.2009.05880.x ref ref name Tuomisto2010b Tuomisto, H. 2010 A diversity of beta diversities straightening up a concept gone awry. Part 2. Quantifying beta diversity and related phenomena. Ecography, 33, 23 45. doi 10.1111 j.1600 0587.2009.06148.x ref Some use beta diversity .... ref Anderson, M. J. et al. 2011 Navigating the multiple meanings of diversity a roadmap for the practicing ..., R. 2011 Commentary Do we have a consistent terminology for species diversity? The fallacy of true diversity. Oecologia 167, 885 888. doi 10.1007 s00442 011 2124 8 ref Others argue that such broad usage should be avoided because it leads to confusion, and that when beta diversity indices correspond ... species diversity? Yes, it does exist. Oecologia 4 853 860. doi 10.1007 s00442 010 1812 0 ref ref Jurasinski, G. and Koch, M. 2011 Commentary do we have a consistent terminology for species diversity .... E and Rodr guez, P. 2011 Commentary Do we have a consistent terminology for species diversity? Back ... ref Tuomisto, H. 2011 Commentary do we have a consistent terminology for species diversity? Yes, if we choose to use it. Oecologia, 167, 903 911. ref Beta diversity in the strict sense Gamma diversity and alpha diversity can be calculated directly from species inventory data. ref name Tuomisto2010a ... more details
Unreferenced stub auto yes date December 2009 Site diversity is a technique to limit the effect of rain fade in satellite communications , mainly in the Ka band . The downlink transmissions of satellites cover very large areas, that will have different weather. The site diversity technique consists of linking two or more ground stations receiving the same signal this way, if the signal is heavily attenuated in one area, another ground stations can compensate it. These intense rain areas, for example supercell s, often have a horizontal length of no more than a few kilometres putting the ground stations at a sufficient distance the possibility of rain fade in the downlink signal will be reduced. The configuration works when the attenuation is not great at the two stations simultaneously. This is usually a valid assumption. Site diversity systems have been known to minimize disruption of service by major satellite carriers. See also Diversity scheme Diversity combining DEFAULTSORT Site Diversity Category Satellite television Comm stub zh ... more details
Biocultural diversitydiversity of life in all its manifestations biology biological , culture cultural , and linguistics linguistic which are interrelated within a complex socio ecological adaptive system. ref http portal.unesco.org education en ev.php URL ID 18391&URL DO DO TOPIC&URL SECTION 201.html UNESCO web page on biocultural diversity ref See also Portal box Ecology Environment Sustainable Development Biocultural anthropology Biocultural evolution Conservation movement Cultural landscape Ecology Ecosystem Environmental protection Terralingua http www.terralingua.org bcdconservation Biocultural Diversity Conservation References Reflist External links http www.unesco.org mab doc iyb icbcd working doc.pdf UNESCO web page on biocultural diversity http www.terralingua.org Terralingua http www.terralingua.org bcdconservation Biocultural Diversity Conservation Category Biodiversity Category Anthropology environment stub anthropology stub ... more details
Unreferenced stub auto yes date December 2009 Image BlueMarble 2001 2002.jpg thumb right 300px alt Two views of the Earth from space. The Earth has many diverse ecosystems and ecosystem diversity. These are NASA composite images of the Earth 2001 left , 2002 right , titled The Blue Marble . seealso Ecosystem Biome Ecosystem diversity refers to the diversity of a place at the level of ecosystem s. The term differs from biodiversity , which refers to variation in species rather than ecosystems. Ecosystem diversity can also refer to the variety of ecosystems present in a biosphere, the variety of species and ecological processes that occur in different physical settings. Examples Some examples of ecosystems that are rich in diversity are Refbegin 3 Deserts Forests Large marine ecosystem s Marine ecosystem s Old growth forest s Rainforest s Tundra Coral Reef s Refend See also Portal box Environment Ecology Earth sciences Sustainable development Refbegin 2 Bioregion Ecology Evolutionary biology Genetic diversity Nature Natural environment Species diversity Sustainable development Refend modelling ecosystems expanded other DEFAULTSORT Ecosystem Diversity Category Biodiversity Category Systems ecology Ecology stub es Diversidad ecol gica sl Ekosistemska diverziteta zh ... more details
Orphan date November 2006 Normgiving Diversity is a former public taxpayer funded program in Sweden , Europe, aimed at encouraging acceptance of lesbian s, Bisexuality bisexuals and gay men in public institutions such as the army, police, etc. External links http www.normgivande.nu NG english.asp Normgiving Diversity Dead link date August 2010 Category Swedish society Sweden stub ... more details
Refimprove date October 2010 Cleanup date March 2012 In sociology and political studies , the term diversity or diverse is used to describe political entities neighborhoods, student bodies, etc with members who have identifiable differences in their cultural backgrounds or lifestyles. The term describes differences in racial or ethnic group ethnic classifications , age, gender , religion , philosophy, disability physical abilities , socioeconomic background, sexual orientation , gender identity , intelligence , mental health , physical health , Genetics genetic attributes, behavior , attractiveness , or other identifying features. In measuring human diversity, a diversity index measures the probability that any two residents, chosen at random, would be of different ethnicities. If all residents are of the same ethnic group it s zero. If half are from one group and half from another it s .50. ref http projects.latimes.com mapping la neighborhoods diversity neighborhood list Mapping L.A.., Los Angeles Times website ref Ideology Main New Left Multiculturalism Political creed s which support the idea that diversity is valuable and desirable hold that recognizing and promoting these diverse cultures may aid communication between people of different backgrounds and lifestyles, leading to greater knowledge, understanding, and peaceful coexistence. Citation needed date August 2007 For example, Respect for Diversity is one of the six principles of the Global Greens Charter , a manifesto subscribed to by Green party Green parties from all over the world. In contrast to diversity, some political creeds promote cultural assimilation as the process to lead to these ends. Use in American academia This use of diversity in this sense also extends to American academia , where in an attempt ... underrepresented fields as the sciences . See also wikiquote Diversity Affirmative ... Diversity business Workplace diversity References Reflist Category Political correctness Category ... more details
Unreferenced stub auto yes date December 2009 Time Diversity is used in digital communication systems to combat that the transmissions channel may suffer from error burst s due to time varying channel conditions. The error bursts may be caused by fading in combination with a moving receiver, transmitter or obstacle, or by intermittent electromagnetic interference, for example from crosstalk in a cable, or co channel interference from radio transmitters. Time diversity implies that the same data is transmitted multiple times, or a redundant error correcting code is added. By means of bit interleaving, the error bursts may be spread in time. See also Diversity reception schemes DEFAULTSORT Time Diversity Category Radio resource management Wireless stub ko zh ... more details
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