Guanine tetrads are not always stable, but the sugar- phosphate backbone of DNA can assist in stability of the guanine tetrads themselves. Guanine tetrads are more stable when stacked, as intermolecular forces between each layers help stabilize them. Guanine tetrads can also influence recombination, replication, and transcription. For instance, guanine tetrads are found in the promoter region of the Myc family of oncogenes.
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Notably, the spores occur in sets of four, called tetrads. Unlike most other species of liverwort, the spores stay in these tetrads until they germinate.
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The pollen of M. macclurei is shed as permanent tetrads.
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The pollen of M. keithii is shed as permanent tetrads.
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The pollen of M. macrocarpa is shed as permanent tetrads.
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The pollen of M. calcarea is shed as permanent tetrads.
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The pollen of A. lutea is shed as permanent tetrads.
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The pollen of M. samarensis is shed as permanent tetrads.
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The pollen of M. petelotii is shed as permanent tetrads.
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The pollen of G. undulatus is shed as permanent tetrads.
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The pollen of P. cerina is shed as permanent tetrads.
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The pollen of M. polypyrena is shed as permanent tetrads.
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The pollen of P. williamsii is shed as permanent tetrads.
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The pollen of P. lucida is shed as permanent tetrads.
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The pollen of P. polyphleba is shed as permanent tetrads.
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The pollen of P. leiophylla is shed as permanent tetrads.
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The pollen of M. williamsii is shed as permanent tetrads.
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The pollen of M. weberi is shed as permanent tetrads.
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The pollen of P. aurantiaca is shed as permanent tetrads.
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The pollen of P. beccarii is shed as permanent tetrads.
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The pollen of A. longiflora is shed as permanent tetrads.
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The pollen of M. laurentii is shed as permanent tetrads.
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The pollen of the species is shed as permanent tetrads.
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The pollen of M. minor is shed as permanent tetrads.
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The pollen of C. elwesii is shed as permanent tetrads.
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The pollen of Annona crassivenia is shed as permanent tetrads.
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The pollen of Annona cordifolia is shed as permanent tetrads.
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The pollen of Annona cascarilloides is shed as permanent tetrads.
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The pollen of Anisophyllea manausensis is shed as permanent tetrads.
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The pollen of Annona acutiflora is shed as permanent tetrads.
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The pollen of Annona angustifolia is shed as permanent tetrads.
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The pollen of M. stenopetala is shed as permanent tetrads.
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The pollen of A. haematantha is shed as permanent tetrads.
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The pollen of A. moaensis is shed as permanent tetrads.
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The pollen of M. winitii is shed as permanent tetrads.
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The pollen of P. beccarii is shed as permanent tetrads.
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The pollen of M. tomentosa is shed as permanent tetrads.
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The pollen of P. calliura is shed as permanent tetrads.
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The pollen of P. bruneiensis is shed as permanent tetrads.
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The pollen of M. carolinae is shed as permanent tetrads.
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The pollen of M. crispata is shed as permanent tetrads.
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The pollen of A. rigida is shed as permanent tetrads.
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The pollen of M. globiflora is shed as permanent tetrads.
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The pollen of M. grandidieri is shed as permanent tetrads.
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The pollen of Annona sericea is shed as permanent tetrads.
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The pollen of M. hastipetala is shed as permanent tetrads.
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The pollen of H. mossambicensis is shed as permanent tetrads.
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The pollen of G. cheliensis is shed as permanent tetrads.
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The pollen of M. junodii is shed as permanent tetrads.
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The pollen of M. fragrans is shed as permanent tetrads.
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The pollen of G. repevensis is shed as permanent tetrads.
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The pollen of G. puncticulifolius is shed as permanent tetrads.
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The pollen of G. monosperma is shed as permanent tetrads.
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The pollen of G. nitidus is shed as permanent tetrads.
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The pollen of G. sawtehii is shed as permanent tetrads.
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The pollen of G. gabriacianus is shed as permanent tetrads.
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The pollen of G. scortechinii is shed as permanent tetrads.
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The pollen of G. ridleyi is shed as permanent tetrads.
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The pollen of G. rongklanus is shed as permanent tetrads.
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The pollen of G. rotundisepalus is shed as permanent tetrads.
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The pollen of G. tamirensis is shed as permanent tetrads.
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The pollen of G. tenuifolius is shed as permanent tetrads.
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The pollen of G. tavoyensis is shed as permanent tetrads.
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The pollen of G. velutinus is shed as permanent tetrads.
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The pollen of G. uvarioides is shed as permanent tetrads.
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The pollen of G. tapis is shed as permanent tetrads.
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The pollen of G. tortilipetalus is shed as permanent tetrads.
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The pollen of H. bussei is shed as permanent tetrads.
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The pollen of Annona bullata is shed as permanent tetrads.
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The pollen of H. bussei is shed as permanent tetrads.
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The pollen of M. alba is shed as permanent tetrads.
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The pollen of H. monopetalus is shed as permanent tetrads.
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The pollen of S. elegans is shed as permanent tetrads.
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The pollen of S. elegans is shed as permanent tetrads.
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The pollen of H. flava is shed as permanent tetrads.
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The pollen of A. haitiensis is shed as permanent tetrads.
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The pollen of M. elliotiana is shed as permanent tetrads.
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The pollen of M. lepidotum is shed as permanent tetrads.
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The pollen of A. macroprophyllata is shed as permanent tetrads.
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The pollen of A. tenuiflora is shed as permanent tetrads.
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The pollen of Annona nutans is shed as permanent tetrads.
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The pollen of Annona sclerophylla is shed as permanent tetrads.
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The pollen of A. stenophylla is shed as permanent tetrads.
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The pollen of Annona pittieri is shed as permanent tetrads.
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The pollen of Annona paludosa is shed as permanent tetrads.
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The pollen of B. longipedunculata is shed as permanent tetrads.
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The pollen of F. peruviana is shed as permanent tetrads.
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The pollen of F. decurrens is shed as permanent tetrads.
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The pollen of D. calycina is shed as permanent tetrads.
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The pollen of B. viridis is shed as permanent tetrads.
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The pollen of C. brandisiana is shed as permanent tetrads.
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The pollen of G. aurantiacus is shed as permanent tetrads.
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The pollen of G. grandiflorus is shed as permanent tetrads.
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The pollen of G. laoticus is shed as permanent tetrads.
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The pollen of G. calvicarpus is shed as permanent tetrads.
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The pollen of G. chartaceus is shed as permanent tetrads.
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The pollen of G. latestigma is shed as permanent tetrads.
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The pollen of G. malayanus is shed as permanent tetrads.
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The pollen of G. macrophyllus is shed as permanent tetrads.
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The pollen of G. maewongensis is shed as permanent tetrads.
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The pollen of G. elegans is shed as permanent tetrads.
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The orange pollen of D. grandiflorus is shed as permanent tetrads.
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The yellow pollen of S. leucanthum is shed as permanent tetrads.
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The yellow pollen of Annona jahnii is shed as permanent tetrads.
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It likewise has utonal tetrads, C-E-G-B, which in the arrangement B-E-G-C becomes Wagner's Tristan chord. It has also the subminor triad, C-D-G, which is otonal, and the supermajor triad, C-F-G, which is utonal. These can be extended to subminor tetrads, C-D-G-A and supermajor tetrads C-F-G-B.
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The flowers have 30-40 carpels. Pollen is shed as permanent tetrads.
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The rest of the sutra explains how the four tetrads fulfill the four satipatthanas and then explains how the practice of the four tetrads of anapanasati fulfill the seven factors of awakening which themselves bring "clear knowing" and release.
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The bright orange-yellow pollen of Annona acuminata is shed as permanent tetrads.
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Buds are long, wide at the base. The pollen is shed as permanent tetrads.
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The pollen of Annona tenuiflora is shed as permanent tetrads. Pollinators include Cyclocephala beetles.
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The pollen of C. cauliflorum is shed as solitary grains with some permanent tetrads.
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The pollen of M. glabra is shed as permanent tetrads. It flowers and sets fruits throughout the year.
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The pollen of Annona foetida is shed as permanent tetrads. It is pollinated by the scarab beetle Cyciocephala undata.
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The pollen of F. longifolia is shed as loose, permanent, tetragonal or tetrahedral tetrads that are 115 micrometers in diameter.
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The pollen of M. heyneana is shed as permanent tetrads. Pollination is believed to be assisted by beetles in the Nitidulidae family.
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The pollen of M. pallens is shed as permanent tetrads. It flowers between February and March and fruits between June and November.
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Using the synonymous name, Mitrephora teysmannii, Yunyun Shao and Fengxia Xu report that the pollen of M. maingayi is shed as permanent tetrads.
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Adolph Göpel (29 September 1812 - 7 June 1847) was a German mathematician who did the first paper on hyperelliptic functions and who introduced Göpel tetrads.
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However, at more than 40 μm in diameter, the tetrads of D. major are larger than those of any known extant Nepenthes, and within the lower range of extant Drosera tetrads. Pollen from the Kerguelen Islands originally described as D. spinosus has also been interpreted as belonging to Nepenthes.Heubl, G., G. Bringmann & H. Meimberg 2006. Molecular phylogeny and character evolution of carnivorous plant families in Caryophyllales — revisited.
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The pollen of G. amuyon is shed as permanent tetrads. Seed germination in laboratory conditions has been optimized at 30°C in light for 4 weeks.
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They also function in immunoglobulin class switching and may play a role in the genome of HIV. Guanine tetrads appear frequently in the telomeric regions of DNA.
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It can be found arranged in pairs, chains, tetrads, cubical arrangements of eight, and irregular clusters. They have rigid cell walls and are either aerobic or facultative anaerobic.
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Annona spraguei is a species of plant in the Annonaceae family. It is endemic to Panama. It is threatened by habitat loss. Its pollen is shed as permanent tetrads.
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The pollen of Asimina reticulata is shed as permanent tetrads. It is pollinated by the dark flower scarab beetle Euphoria sepulcralis and the hairy flower scarab beetle Trichiotinus rufobrunneus.
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It is a small bush 2 to 3 feet in height. Prominent features include long narrow leaves, 4 by inches, and white flowers. Its pollen is shed in permanent tetrads.
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Compared to the pale yellow or cream color of the petals, the inner base of the A. glabra flower is a bright red. Its pollen is shed as permanent tetrads.
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Buddha statue doing anapanasati Ānāpānasati (Pali; Sanskrit ānāpānasmṛti), meaning "mindfulness of breathing" ("sati" means mindfulness; "ānāpāna" refers to inhalation and exhalation), is a form of Buddhist meditation originally taught by Gautama Buddha in several suttas including the Ānāpānasati Sutta.In the Pali canon, the instructions for anapanasati are presented as either one tetrad (four instructions) or four tetrads (16 instructions). The most famous exposition of four tetrads – after which Theravada countries have a national holiday (see uposatha) – is the Anapanasati Sutta, found in the Majjhima Nikaya sutta 118 (for instance, see Thanissaro, 2006). Other discourses which describe the full four tetrads can be found in the Samyutta Nikaya's Anapana- samyutta (Ch. 54), such as SN 54.6 (Thanissaro, 2006a), SN 54.8 (Thanissaro, 2006b) and SN 54.13 (Thanissaro, 1995a).
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In molecular biology, a guanine tetrad (also known as a G-tetrad or G-quartet) is a structure composed of four guanine bases in a square planar array. They most prominently contribute to the structure of G-quadruplexes, where their hydrogen bonding stabilizes the structure. Usually, there are at least two guanine tetrads in a G-quadruplex, and they often feature Hoogsteen-style hydrogen bonding. Guanine tetrads are formed by sequences rich in guanine, such as GGGGC.
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The pollen of Annona dioica is shed as permanent tetrads. Plants are androdioecious with flowers that are both male and female, or male only. Pollination is mediated by the Cyclocephala atricapilla beetle.
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It has showy flowers and fruits. Its pollen is shed as permanent tetrads. It grows in evergreen forest habitat. This is a vulnerable species threatened by habitat loss as forest is cleared for agriculture.
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For a finite field GF(q), the projective line is the Galois geometry PG(1, q). J. W. P. Hirschfeld has described the harmonic tetrads in the projective lines for q = 4, 5, 7, 8, 9.
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Droserapites is a genus of extinct plants of somewhat uncertain droseracean affinity. It is a form taxon known only from fossil pollen. Droserapites pollen grains are united in tetrads (groups of four). Individual grains are inaperturate.
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At some typical boundary regions such as null infinity, timelike infinity, spacelike infinity, black hole horizons and cosmological horizons, null tetrads adapted to spacetime structures are usually employed to achieve the most succinct Newman–Penrose descriptions.
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The complete row of Pascal's triangle for the hypercube in this construction runs 1 (single vertex), 4 (tetrahedron tetrad), 6 (hexany), 4 (another tetrad), 1. The idea generalises to other numbers of dimensions, for instance, the cross-sections of a five-dimensional cube give two versions of the dekany, a ten-note scale rich in tetrads, triads and dyads, which also contains many hexanies. In six dimensions the same construction gives the twenty-note eikosany, which is even richer in chords. It has pentads, tetrads, and triads as well as hexanies and dekanies.
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Droserapollis is a genus of extinct plants in the family Droseraceae. It is a form taxon known only from fossil pollen. Droserapollis pollen grains are united in tetrahedral tetrads (groups of four). Individual grains are possibly porate-like.
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Fossil pollen records of extant angiosperms in China. The Botanical Review 70(4): 425–458. The tetrads of D. gemmatus are 53–56 μm in deter. Individual grains are prolate and measure 35–40 by 25–26 μm.
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The paired and replicated chromosomes are called bivalents (two chromosomes) or tetrads (four chromatids), with one chromosome coming from each parent. Prophase I is divided into a series of substages which are named according to the appearance of chromosomes.
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It is a small to medium tree reaching a maximum of . It is deciduous with hairy leaves and large, strong-scented flowers. Online at Purdue University Center for New Crops and Plant Products. Its pollen is shed as permanent tetrads.
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The pollen of Asimina pygmaea is shed as permanent tetrads. It is pollinated by the dark flower scarab beetle Euphoria sepulcralis. Its flowers produce several scent compounds including dimethyl sulfide which is associated with carrion odor and may attract beetle pollinators.
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The quadruplex structure is further stabilized by the presence of a cation, especially potassium, which sits in a central channel between each pair of tetrads. They can be formed of DNA, RNA, LNA, and PNA, and may be intramolecular, bimolecular, or tetramolecular. Depending on the direction of the strands or parts of a strand that form the tetrads, structures may be described as parallel or antiparallel. G-quadruplex structures can be computationally predicted from DNA or RNA sequence motifs, but their actual structures can be quite varied within and between the motifs, which can number over 100,000 per genome.
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The tree is similar to Annona muricata, but has a more spreading crown and glossy leaves. It is slightly hardier and bears fruit throughout the year. It tolerates brief temperature drops down to when full grown. Its pollen is shed as permanent tetrads.
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Micrococcus lylae is a gram positive bacterium. The normal habitat for this Micrococcus species is skin, dust, and water. Its type strain is ATCC 27566. It grows in tetrads, irregular clusters, and cubical packets of eight, and colonies are often brightly pigmented.
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The pollen of Annona aurantiaca is shed as permanent tetrads. Its flowers open over a two night period with a female phase on the first night, and a male phase on the second night. It is pollinated by the scarab beetle Cyclocephala atricapilla.
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The cells are coccoid. Cells are 1-2.5 μm. Cell division is carried out in two or three successive planes, such that tetrads or packets of eight or more cells are formed. S. ureae forms endospores (like all species of the genus).
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The flower is pink to maroon in color, changing color as it ages, and has a fetid scent. It has usually four sepals and six petals. The fruit is a yellow-green, banana- scented aggregate. Its pollen is shed as permanent tetrads.
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Grisellatheca was a genus of land plant with branching axes. It is known from charcoalified Early Devonian deposits, its type locality being the Brown Clee Hill lagerstatten. Its Terahedraletes spores form permanent tetrads. Grisellatheca's internal anatomy comprises banded tubes, but it lacked an external cuticle.
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The genus Anaerococcus are non motile bacteria who can not form spores and. Depending of the species the arrangement can be different. The most common arrangements within this genus are pairs, tetrads, short chains and irregular formations. Their cells size can differ from 0.6μm to 0.9μm.
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Molecular phylogeny of Nepenthaceae based on cladistic analysis of plastid trnK intron sequence data. Plant Biology (Stuttgart) 3(2): 164–175. This genus is characterised by inaperturate and spinose pollen grains that are united in loose tetrahedral tetrads (groups of four). The grains are prolate, striate, and tricolpate.
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Plant Biology 8(6): 821–830. Some authors consider D. major and D. parvus as synonyms of Nepenthidites laitryngewensis of the Palaeocene Lakadong Sandstone in Laitryngew, Khasi Hills, Meghalaya, India.Kumar, M. 1995. Pollen tetrads from Palaeocene sediments of Meghalaya, India: comments on their morphology, botanical affinity and geological records.
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The definition of tetrads and pentads introduce further sophistication and precision to defining tacticity, especially when information on long-range ordering is desirable. Tacticity measurements obtained by Carbon-13 NMR are typically expressed in terms of the relative abundance of various pentads within the polymer molecule, e.g. mmmm, mrrm.
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Haloterrigena turkmenica is a gram-negative organism. Cells are typically found as individuals, but have been seen in the form of pairs and tetrads. Cell shape can be classified as being ovoid to coccoid in shape. The diameter of the cells ranges from 1.5 µm to 2.0 µm.
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Spores of Riccia sorocarpa still associated in tetrads following meiosis. The tetrad is the four spores produced after meiosis of a yeast or other Ascomycota, Chlamydomonas or other alga, or a plant. After parent haploids mate, they produce diploids. Under appropriate environmental conditions, diploids sporulate and undergo meiosis.
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Genetic Recombination. New York: Wiley; 1982. These studies have proven central to understanding the mechanism of meiotic recombination, which in turn is a key to understanding the adaptive function of sexual reproduction. The use of tetrads in fine-structure genetic analysis is described in the articles Neurospora crassa and Gene conversion.
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Staphylococcus auricularis is a Gram-positive member of the bacterial genus Staphylococcus consisting of pairs or tetrads of cocci. This species was originally isolated from the exterior of a human ear and is weakly hemolytic. Because it commonly exists on human skin, it may be able to cause opportunistic infections or sepsis.
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The three inner petals are almost triangular and form a white-yellowish cone which on the outside is red-spotted and green on the inside. The flower’s stigmas become receptive before its stamens mature and shed their pollen (protogynous). Its pollen is shed as permanent tetrads. . The flower is pollinated by insects.
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They are helical in shape and contain guanine tetrads that can form from one, two or four strands. The unimolecular forms often occur naturally near the ends of the chromosomes, better known as the telomeric regions, and in transcriptional regulatory regions of multiple genes, both in microbes and across vertebrates including oncogenes in humans. Four guanine bases can associate through Hoogsteen hydrogen bonding to form a square planar structure called a guanine tetrad (G-tetrad or G-quartet), and two or more guanine tetrads (from G-tracts, continuous runs of guanine) can stack on top of each other to form a G-quadruplex. The placement and bonding to form G-quadruplexes is not random and serve very unusual functional purposes.
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Pediococcus acidilactici is a species of Gram-positive cocci that is often found in pairs or tetrads. P. acidilactici is a homofermentative bacterium that can grow in a wide range of pH, temperature, and osmotic pressure, therefore being able to colonize the digestive tract.Klaenhammer T.R. 1993. Genetics of bacteriocins produced by lactic acid bacteria.
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Pediococcus is a genus of gram-positive lactic acid bacteria, placed within the family of Lactobacillaceae. They usually occur in pairs or tetrads, and divide along two planes of symmetry, as do the other lactic acid cocci genera Aerococcus and Tetragenococcus. They are purely homofermentative. Pediococcus dextrinicus has recently been reassigned to the genus Lactobacillus.
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Envelope-enclosed spore tetrads are taken as the earliest evidence of plant life on land, dating from the mid-Ordovician (early Llanvirn, ~), a period from which no macrofossils have yet been recovered. Individual trilete spores resembling those of modern cryptogamic plants first appeared in the fossil record at the end of the Ordovician period.
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The spindle assembly checkpoint (SAC) is a molecular safe-guarding mechanism that governs proper chromosome segregation in eukaryotic cells. SAC inhibits progression into anaphase until all homologous chromosomes (bivalents, or tetrads) are properly aligned to the spindle apparatus. Only then, SAC releases its inhibition of the anaphase promoting complex (APC), which in turn irreversibly triggers progression through anaphase.
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Micrococcus (mi’ krō kŏk’ Əs) is a genus of bacteria in the Micrococcaceae family. Micrococcus occurs in a wide range of environments, including water, dust, and soil. Micrococci have Gram-positive spherical cells ranging from about 0.5 to 3 micrometers in diameter and typically appear in tetrads. They are catalase positive, oxidase positive, indole negative and citrate negative.
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Pyrolaceae, as part of the Ericales produce pollen in anthers which open by apical pores. The pollen itself is produced in tetrads and is rather sticky. Not surprisingly, wintergreens are insect pollinated, most commonly by flies. The rather large and complex stigma may be an adaptation to ensure that small insects carrying pollen have an attractive landing place.
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In his formal description of the genus, Tseng-Chieng Huang suggested that Droserapites may be related to Droseridites and Quadrisperites. The tetrads of D. clavatus are tetrahedral and 34–40 μm in diameter. Individual grains are subspheroidal and measure 18–25 μm in width. They have a roughly circular amb that is abruptly acute at the distal pole.
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Stamens are alternating with the petals and have short filaments. The anthers are connected to the filaments at their base, open in lengthwise slids towards the inside, through which the yellow pollen is shed in tetrads. The stigma is bud-shaped, with a dark bluish purple top. The pistil is shed after the petals and anthers.
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Kytococcus sedentarius is a marine dwelling Gram positive bacterium in the genus Kytococcus. It is known for the production of polyketide antibiotics as well as for its role as an opportunistic pathogen. It is strictly aerobic and can only grow when amino acids are provided. It is found in tetrads, irregular clusters, and cubical packets of eight.
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Droseraceae are carnivorous herbaceous plants that may be annuals or perennials. Their leaves are alternate and adaxially circinate, with at least one leaf surface containing hairs with mucilage- producing glands at the tip. Their flowers are bisexual, usually with three carpels and five sepals, petals and stamens. Their pollen grains are triporate or multiporate and released in tetrads.
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Deposits often appear on the sieve plates at the end of the growing season. Callose also forms immediately around the developing meiocytes and tetrads of sexually reproducing angiosperms but is not found in related apomictic taxa. Callose deposition at the cell wall has been suggested as an early marker for direct somatic embryogenesis from cortical and epidermal cells of Cichorium hybrids.
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The classical method of diagnosis is to culture aliquots of haemolymph in phenylethyl alcohol broth. Cultures containing A. viridans var. homari change colour from purple to yellow, and form tetrads of cocci. To reduce the four-day waiting time needed for diagnosis, a method using the indirect fluorescent antibody technique (IFAT) was developed, and, more recently, PCR-based methods have been developed.
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The opposite flat leaves have a distinct stem and are thick, fleshy and round, and can be up to 6 cm in length. The inflorescence is an umbel of two or more triads or tetrads (flowering in a group of four). The mature buds are terete (long and cylindrical) or angular, and smooth or with just a few scattered hairs.
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They may also play a role in the dimerization of non-endogenous RNAs to facilitate the replication of some viruses. Guanine tetrads dimerize through their 5' ends since it is more energetically favorable in terms of free energy. They can be stabilized by central cations, such as lithium, sodium, potassium, rubidium, or cesium. However, they still form a variety of different structures.
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Furthermore, there have been 62 tetrads since the 1st century AD, though only eight of them have coincided with both feasts. Additionally, three of the four eclipses in the tetrad were not even visible in the biblical homeland of Israel, casting further doubt on Hagee and Biltz's interpretation; even then, only the very end of the last eclipse was visible in Israel.
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The inflorescence is a solitary flower nodding or held upright on a short peduncle. The sweet-scented flowers have varying numbers of fleshy white or pink-tinged petals that measure 2 or 3 centimeters long. The sweet fragrance of the flowers in this species is caused by benzenoid compounds including veratrole, and the alcohol linalool. Its pollen is shed as permanent tetrads.
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218), for example, Gamer shows how that work employs a 24-tone set generated from a single trichord. In “Lieder to texts by Rainer Maria Rilke” he employs all-trichord sets, each containing an all-interval tetrad, enabling him to embed quotations from tonal music into the serial texture. (Regarding all-interval tetrads, see his article “Microtones and projective planes,” p.
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Crosses are performed between haploid MATa and MATα mating strains, then the resulting diploids are transferred to sporulation media to form a tetrad containing four haploid spores. Tetrads can then be prepared with Zymolyase, or another enzyme, to digest the wall of the ascus. The spores are then separated with a micromanipulator needle and deposited in separate positions on a petri dish.
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In 1961, Møller showed that a tetrad description of gravitational fields allows a more rational treatment of the energy-momentum complex than in a theory based on the metric tensor alone. The advantage of using tetrads as gravitational variables was connected with the fact that this allowed to construct expressions for the energy-momentum complex which had more satisfactory transformation properties than in a purely metric formulation.
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Deletion breakpoints frequently occur within or near regions showing non-canonical (non-B) conformations, namely hairpins, cruciforms and cloverleaf-like elements. Moreover, there is data supporting the involvement of helix-distorting intrinsically curved regions and long G-tetrads in eliciting instability events. In addition, higher breakpoint densities were consistently observed within GC-skewed regions and in the close vicinity of the degenerate sequence motif YMMYMNNMMHM.
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Anthers with filaments hairless or hairy, thecae usually unequal, anthers basifixed, pollen grains free or in tetrads; Nectary pelviform, bilobed; style thread-like, hollow or solid, almost as long as longest stamens, the stigma spoon-shaped. Capsules small (circa 3–4 mm) hidden in bases of persistent calyces; seeds between two and twenty-five in number, depending on species. Testa reticulate or granulate, embryo of seed curved.
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The school arranges numerous regular extracurricular activities for all students. Annual school events include reading activities, dance festivals, music festivals, drama performances, Chinese cultural week, swimming galas, sports days and summer camp. The school has been a vanguard of project-based learning since 1990s, when the approach was relatively new to many Hong Kong secondary schools. Students, divided into tetrads or pentads, have to finish a project throughout their summer vacation.
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Kocuria kristinae, formerly known as Micrococcus kristinae is a gram positive bacteria first isolated from the rhizoplane of the Typha angustifolia The normal habitat for this Kocuria species is skin, and has also been found in the urinary tract of patients with urinary tract infections. Its type strain is ATCC 27566. It is associated with acute cholecystitis. It grows in tetrads, irregular clusters, and cubical packets of eight.
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Sets of higher cardinalities are called tetrachords (or tetrads), pentachords (or pentads), hexachords (or hexads), heptachords (heptads or, sometimes, mixing Latin and Greek roots, "septachords"),E.g., Rahn (1980), 140. octachords (octads), nonachords (nonads), decachords (decads), undecachords, and, finally, the dodecachord. A time-point set is a duration set where the distance in time units between attack points, or time-points, is the distance in semitones between pitch classes.
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Spinors find several important applications in relativity. Their use as a method of analysing spacetimes using tetrads, in particular, in the Newman–Penrose formalism is important. Another appealing feature of spinors in general relativity is the condensed way in which some tensor equations may be written using the spinor formalism. For example, in classifying the Weyl tensor, determining the various Petrov types becomes much easier when compared with the tensorial counterpart.
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Meiosis I segregates homologous chromosomes, which are joined as tetrads (2n, 4c), producing two haploid cells (n chromosomes, 23 in humans) which each contain chromatid pairs (1n, 2c). Because the ploidy is reduced from diploid to haploid, meiosis I is referred to as a reductional division. Meiosis II is an equational division analogous to mitosis, in which the sister chromatids are segregated, creating four haploid daughter cells (1n, 1c). Meiosis Prophase I in mice.
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Chromosomes condense further during the diakinesis stage, from Greek words meaning "moving through". This is the first point in meiosis where the four parts of the tetrads are actually visible. Sites of crossing over entangle together, effectively overlapping, making chiasmata clearly visible. Other than this observation, the rest of the stage closely resembles prometaphase of mitosis; the nucleoli disappear, the nuclear membrane disintegrates into vesicles, and the meiotic spindle begins to form.
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This therefore means that , where one of the points in the two tetrads overlap, hence meaning that other lines connecting the other three pairs must coincide to preserve cross ratio. Therefore, are collinear. Another proof for Pascal's theorem for a circle uses Menelaus' theorem repeatedly. Dandelin, the geometer who discovered the celebrated Dandelin spheres, came up with a beautiful proof using "3D lifting" technique that is analogous to the 3D proof of Desargues' theorem.
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For a more comprehensive view of black holes in quasilocal definitions, adapted tetrads which can be smoothly transited from the exterior to the near-horizon vicinity and to the horizons are required. For example, for isolated horizons describing black holes in equilibrium with their exteriors, such a tetrad and the related coordinates can be constructed this way.Xiaoning Wu, Sijie Gao. Tunneling effect near weakly isolated horizon. Physical Review D, 2007, 75(4): 044027.
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Traditionally, tetrad dissection has a reputation as "black art".Yeast Protocols: Methods in Cell and Molecular Biology, Ivor Howell Evan, Published by Humana Press, 1996, , However, instruments have since been developed specifically for tetrad dissection; the most advanced allow easy and semi-automated separation of tetrads. Most micromanipulators use a glass fiber needle to which the spores adhere due to the formation of a water meniscus between the agar and the needle.
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Gnostics structured their world of transcendent being by ontological distinctions. The plenitude of the divine world emerges from a sole high deity by emanation, radiation, unfolding and mental self-reflection. The technique of self-performable contemplative mystical ascent towards and beyond a realm of pure being, which is rooted in Plato's Symposium and was common in Gnostic thought, was also expressed by Plotinus. Divine triads, tetrads, and ogdoads in Gnostic thought often are closely related to Neo-Pythagorean arithmology.
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The Ānāpānasati Sutta (Pāli) or Ānāpānasmṛti Sūtra (Sanskrit), "Breath- Mindfulness Discourse," Majjhima Nikaya 118, is a discourse that details the Buddha's instruction on using awareness of the breath (anapana) as an initial focus for meditation. The sutta includes sixteen steps of practice, and groups them into four tetrads, associating them with the four satipatthanas (placings of mindfulness). According to American scholar monk, Thanissaro Bhikkhu, this sutta contains the most detailed meditation instructions in the Pali Canon.Thanissaro Bhikkhu.
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They are as follows:Analayo, Mindfulness of Breathing in the Samyukta-agama. Buddhist Studies Review 24(2) 2007,137-50 doi: 10.1558/bsrv.v24i1.l37This enumeration of the core instructions is largely based on Thanissaro (2006a) and Nanamoli (1998). The basis for mapping each of the tetrads to one of the four satipatthana is that, in the Anapanasati Sutta, after what is here identified as the "core instructions," the Buddha explicitly identifies each tetrad as related to a particular satipatthana.
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Total penumbral eclipses constitute a relatively small fraction of lunar eclipses, and the distribution of these events is uneven, occurring between 0 and 9 times per century. The period of this variation is approximately 600 years and also correlates with the frequency of total umbral eclipses and tetrads. The maximum number in Fred's 5K canonTotal penumbral lunar eclipses are indicated by the Nx eclipse type in Fred Espenak's Lunar Eclipse canon. is eight for saros 19.
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Knoellia remsis (formerly Tetrasphaera remsis) a species of Gram positive, nonmotile, non-sporeforming bacteria. The bacteria are aerobic and mesophilic, and the cells are coccoid that group in pairs, tetrads, or clusters. It was originally isolated from an air sample from the Regenerative Enclosed Life Support Module Simulator, which was a system designed to simulate life aboard the International Space Station. The species is named after REMS, the acronym for the Regenerative Enclosed Life Support Module Simulator.
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Custard apple for sale at a fruit vendor near Sangareddi, Telangana, India It is a small deciduous or semi- evergreen tree reaching to tall with an open, irregular crown. The slender leaves are hairless, straight and pointed at the apex (in some varieties wrinkled), to long and to wide. The yellow-green flowers are generally in clusters of three or four to diameter, with three long outer petals and three very small inner ones. Its pollen is shed as permanent tetrads.
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This arrangement minimizes the chance of self-fertilisation. Studies have shown that the operculate pollen shed in tetrads (fused groups of four pollen grains), characteristics that are similar in the related Dionaea muscipula (the Venus flytrap) and Aldrovanda vesiculosa, is incompatible with clones, failing to produce seed when plants are self-fertilised. Seeds are brown to black, linear and ornamented with fine network-like markings, and 2 mm long and 0.5 mm in diameter. Seed is shed by the end of March.
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Large tetrads are occasionally observed, particularly when cells in stationary growth phase are transferred to fresh media. However, it is unknown whether this stage is the product two consecutive mitotic divisions, or perhaps a process that generates sexually competent motile cells (i.e. gametes), or is the end result of meiosis following gamete fusion. There is no cytological evidence for sexual recombination, and meiosis has never been observed, but population genetic evidence supports the view that Symbiodinium periodically undergo events of sexual recombination.
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The fourth paralogism is passed over lightly or not treated at all by commentators. In the first edition of the Critique of Pure Reason, the fourth paralogism is addressed to refuting the thesis that there is no certainty of the existence of the external world. In the second edition of the Critique of Pure Reason, the task at hand becomes the Refutation of Idealism. Sometimes, the fourth paralogism is taken as one of the most awkward of Kant's invented tetrads.
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Stomatococcus mucilaginous (now known as Rothia mucilaginosa) is a Gram- positive, coagulase-negative, encapsulated, non-spore-forming and non-motile coccus, present in clusters, tetrads or pairs that is a part of the normal oropharyngeal flora. Belonging to the family Micrococcaceae, it was first isolated from the mucous membrane of the cheek and gingiva. It is an oral commensal, that has been linked to causing severe bacteremia in immunocompromised patients.Sadikot, Ruxana T.; Yuan, Zhihong; Panchal, Dipti; Syed, Mansoor Ali; Mehta, Hiren; Joo, Myungsoo; Hadid, Walid (October 2013).
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Stomatococcus mucilaginous is a Gram-positive, coagulase- negative, encapsulated, non-spore-forming and non-motile coccus, present in clusters, tetrads or pairs. S. mucilaginous can easily be confused for the bacteria from the genera Micrococcus and Staphylococcus. One way that it can be distinguished from those two is by its strong adherence to the solid medium substrate that its colonies form. Another way is by its weak or absent catalase reaction, failure to grow on 5% NaCl media or its glucose and sucrose fermentation.
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The Pagasetic Gulf in southeastern Thessaly was and is the only body of water suitable for harbours in region. Strictly speaking, Thessaly refers primarily to the central plains inhabited by the Thessalians in antiquity. The plains were divided in antiquity into four administrative regions called tetrads: Pelasgiotis, Phthiotis, Thessaliotis, and Histiaeotis. In its broader sense, Thessaly also included the surrounding regions called the perioikoi, which were regions inhabited by different ethnic groups that were closely tied to the Thessalians either as subordinates, dependents, or allies.
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Some medieval era Indian texts on Yoga list Rajayoga as one of many types of yoga. For example, the Sarvanga yoga pradipikå, a Braj-bhashya commentary by Sundardas, from the 17th-century, teach three tetrads of Yogas. The first group is Bhakti yoga, Mantra yoga, Laya yoga, and Carcha yoga; the second group is Hatha yoga, Raja yoga, Laksha yoga, and Ashtanga yoga; the third is Samkhya yoga, Jñana yoga, Brahma yoga, and Advaita yoga. Of these twelve, Sundardas states that Rajayoga is the best yoga.
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Next, the 16 objects or instructions are listed, generally broken into four tetrads. These core sixteen steps are one of the most widely taught meditation instructions in the early Buddhist texts. They appear in various Pali suttas like the Ananada sutta not just the Anapanasati sutta. They also appear in various Chinese translations of the Agamas (such as in a parallel version of the Ananada sutta in the Samyukta-Agama, SA 8.10) with minor differences as well as in the Vinayas of different schools.
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They display alternation of generations; in addition to gametophyte generation, many have two sporophyte generations, the carposporophyte- producing carpospores, which germinate into a tetrasporophyte – this produces spore tetrads, which dissociate and germinate into gametophytes. The gametophyte is typically (but not always) identical to the tetrasporophyte. Carpospores may also germinate directly into thalloid gametophytes, or the carposporophytes may produce a tetraspore without going through a (free- living) tetrasporophyte phase. Tetrasporangia may be arranged in a row (zonate), in a cross (cruciate), or in a tetrad.
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In the second phase of prophase I, zygotene (from the Greek for "conjugation"), all maternally and paternally derived chromosomes have found their homologous partner. The homologous pairs then undergo synapsis, a process by which the synaptonemal complex (a proteinaceous structure) aligns corresponding regions of genetic information on maternally and paternally derived non-sister chromatids of homologous chromosome pairs. The paired homologous chromosome bound by the synaptonemal complex are referred to as bivalents or tetrads. Sex (X and Y) chromosomes do not fully synapse because only a small region of the chromosomes are homologous.
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Two alternative positions of sodium observed, and sodium can only interacts with four rather than eight oxygens. The tertiary structure of TBA is an anti-parallel G-quadruplex. This chair-like structure is folded through the stacking of two guanine (G)-tetrads, and four guanines interacts with one another through non Watson-Crick-like hydrogen bonds (more likely Hoogsteen-like hydrogen bonds). In the structure of TBA, G1, G6, G10 and G15 form the top layer of G-tetrad; G2, G5, G11 and G14 form the second layer.
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In 1961, Møller showed that a tetrad description of gravitational fields allows a more rational treatment of the energy-momentum complex than in a theory based on the metric tensor alone. The advantage of using tetrads as gravitational variables was connected with the fact that this allowed to construct expressions for the energy-momentum complex which had more satisfactory transformation properties than in a purely metric formulation. Recently it has been shown that total energy of matter and gravitation is proportional to the Ricci scalar of three-space up to linear order of perturbation.
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The genus Tetraspora was first described by Link ex Desvaux in the year 1818, where the purpose for the genus was to organize algae with spores arranged in confirmations of tetrads. In the very first classifications, species of Tetraspora were classified into the order Tetrasporales under Chlorophyta. However, with molecular analysis, it was found that Tetraspora species had similar basal body morphology to Chlamydomonas and also had molecular similarity in the SSU rDNA. This changed the classification from being under the order Tetrasporales to order Volvocales, where they still reside today.
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The group was formerly included in the genus Clitocybe, but in 2003 was erected to genus level to accommodate species for which mycelium cannot reduce nitrate and basidiospores do not adhere in tetrads, but exhibit a lacrymoid (tear-shaped) morphology, a confluent base and a cyanophobic basidiospore wall. The genus contains 19 widespread species according to the Index Fungorum and one new species I. rufa, only known from high altitude localities in southwestern China, described in 2016. The type species of the genus, as defined by the author Harmaja, is I. gibba.
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A mitosis-like cell cycle would proceed until the viral membranes dissolved, at which point linear chromosomes would be bound together with centromeres. The homologous nature of the two viral centromeres would incite the grouping of both sets into tetrads. It is speculated that this grouping may be the origin of crossing over, characteristic of the first division in modern meiosis. The partitioning apparatus of the mitotic-like cell cycle the cells used to replicate independently would then pull each set of chromosomes to one side of the cell, still bound by centromeres.
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Meiosis I of ootidogenesis begins during embryonic development, but halts in the diplotene stage of prophase I until puberty. The mouse oocyte in the dictyate (prolonged diplotene) stage actively repairs DNA damage, whereas DNA repair is not detectable in the pre- dictyate (leptotene, zygotene and pachytene) stages of meiosis. For those primary oocytes that continue to develop in each menstrual cycle, however, synapsis occurs and tetrads form, enabling chromosomal crossover to occur. As a result of meiosis I, the primary oocyte has now developed into the secondary oocyte and the first polar body.
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Synthetic CpG ODN differ from microbial DNA in that they have a partially or completely phosphorothioated (PS) backbone instead of the typical phosphodiester backbone and a poly G tail at the 3' end, 5' end, or both. PS modification protects the ODN from being degraded by nucleases such as DNase in the body and poly G tail enhances cellular uptake. The poly G tails form intermolecular tetrads that result in high molecular weight aggregates. These aggregates are responsible for the increased activity the poly G sequence impart; not the sequence itself.
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Ashtekar variables, which were a new canonical formalism of general relativity, raised new hopes for the canonical quantization of general relativity and eventually led to loop quantum gravity. Smolin and others independently discovered that there exists in fact a Lagrangian formulation of the theory by considering the self-dual formulation of the Tetradic Palatini action principle of general relativity. These proofs were given in terms of spinors. A purely tensorial proof of the new variables in terms of triads was given by Goldberg and in terms of tetrads by Henneaux et al..
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The utonal tetrad, the inversion of the otonal tetrad, is spelled C-D- G-G. Further septimal chords are the diminished triad, having the two forms C-D-G and C-F-G, the subminor triad, C-F-G, the supermajor triad C-D-G, and corresponding tetrads C-F-G-B and C-D-G-A. Since 53-EDO tempers out the septimal kleisma, the septimal kleisma augmented triad C-F-B in its various inversions is also a chord of the system. So is the Orwell tetrad, C-F-D-G in its various inversions.
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However, a translational gauge symmetry may be introduced thus: Instead of seeing tetrads as fundamental, we introduce a fundamental translational gauge symmetry instead (which acts upon the internal Minkowski space fibers affinely so that this fiber is once again made local) with a connection and a "coordinate field" taking on values in the Minkowski space fiber. More precisely, let be the Minkowski fiber bundle over the spacetime manifold . For each point , the fiber is an affine space. In a fiber chart , coordinates are usually denoted by , where are coordinates on spacetime manifold , and are coordinates in the fiber .
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ASOs have previously been used to restore normal phenotypes in other neurological diseases that have gain-of-function mechanisms, the only difference is that it was used in the absence of G-quadruplex expansion repeat regions. Another commonly used technique is the utilization of small-molecule ligands. These can be used to target G-quadruplex regions that cause neurological disorders. Approximately 1,000 various G-quadruplex ligands exist in which they are able to interact via their aromatic rings; this allows the small-molecule ligands to stack on the planar terminal tetrads within the G-quadruplex regions.
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Lambertia multiflora The proteaceae have a rich fossil record, despite the inherent difficulties in identifying remains that do not show diagnostic characteristics. Identification usually comes from using a combination of brachy-paracytic stomata and the unusual trichome bases or, in other cases, the unusual structure of pollen tetrads. Fossils attributable to this family have been found on the majority of areas that formed the Gondwana supercontinent. A wide variety of pollen belonging to this family dating back to the Upper Cretaceous (Campanian-Maastrichtian) from the south east of Australia and pollen from the Middle Cretaceous (Cenomanian-Turonian) from northern Africa and Peru described as Triorites africaensis.
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They are helical in shape and contain guanine tetrads that can form from one, two or four strands. ;D-loop: A displacement loop or D-loop is a DNA structure where the two strands of a double-stranded DNA molecule are separated for a stretch and held apart by a third strand of DNA. An R-loop is similar to a D-loop, but in this case the third strand is RNA rather than DNA. The third strand has a base sequence which is complementary to one of the main strands and pairs with it, thus displacing the other complementary main strand in the region.
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The most important were the Aleuadae of Larissa, the Echecratidae of Pharsalus, and the Scopadae of Crannon. Their clan chiefs were often called basileis ("kings"). It was Aleuas Pyrrhos ("the Red") who cemented the aristocracy's predominance by reforming the Thessalian League on the basis of the "tetrads" (quadripartite division), linking it with the noble-controlled kleroi ("land lots") obliged to supply 40 horsemen and 80 infantrymen each. Traditionally, the office of tagus has been regarded as the senior magistrate of the Thessalian League; more recent studies however regard the tagus as a purely local official, and suggest the tetrarches as the head of the League.
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Under the microscope, Pediococcus often appear in pairs of pairs or tetrads which can make them identifiable. Pediococci are homofermenters, metabolizing glucose into a racemic mixture of both L- and D-lactate by glycolysis. However, in the absence of glucose, some species, such as P. pentosaceus, begin using glycerol, degrading it into pyruvate which later can be converted to diacetyl, acetate, 2,3-butanediol and other compounds that can impart unfavorable characteristics to the wine. Most Pediococcus species are undesirable in winemaking due to the high levels of diacetyl that can be produced, as well as increased production of biogenic amines that has been implicated as one potential cause for red wine headaches.
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MaxDiff and most- least methods belong to a class of methods that do not require the estimation of a cognitive parameter as occurs in the analysis of ratings data. This is one of the reasons for their popularity in applications. Other methods in this class include the 2- and 3-alternative forced choice methods, the triangular method which is a special case of Richardson's method, the duo-trio method and the specified and unspecified methods of tetrads. All of these methods have well developed Thurstonian scaling models as discussed recently in Ennis (2016) which also includes a Thurstonian model for first-last or most-least choice and ranks with rank-induced dependencies.
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They have also been used to model long-term memory in ranking tasks of ordered alternatives, such as the order of the amendments to the US Constitution. Their main advantage over other models ranking tasks is that they account for non-independence of alternatives. Ennis provides a comprehensive account of the derivation of Thurstonian models for a wide variety of behavioral tasks including preferential choice, ratings, triads, tetrads, dual pair, same-different and degree of difference, ranks, first-last choice, and applicability scoring. In Chapter 7 of this book, a closed form expression, derived in 1988, is given for a Euclidean-Gaussian similarity model that provides a solution to the well-known problem that many Thurstonian models are computationally complex often involving multiple integration.
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Carcinogenesis is a multistep process; tumours also contain activated Ras, as well as mutation or downregulation of the tumour suppressor genes p53 in alimentary tract cancers and fragile histidine tetrads (FHIT) in urinary bladder cancers. Viral particles are not produced in either alimentary tract or urinary bladder tumours. Cows feeding on bracken are at risk of developing BPV-associated cancers These bracken-associated tumours might form a model for some types of human oesophageal cancer. Human papillomavirus DNA has been detected in around 18% of squamous cell carcinomas of the oesophagus, and there is an association between exposure to or consumption of bracken (which is used as a foodstuff and herbal remedy in South America, China, Japan, Korea and other countries) and risk of developing oesophageal cancer.
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When the military result was not finalized, Pelopidas was summoned to enter the protracted struggle between Alexander II and Ptolemy Aloros in Macedonia- the Theban general, however, urged rearrangement of the Thessalian League at that time. The most important parts of the rearrangement were the replacement of the tagos by an archon, and the reorganization of the Thessalian army according to the four tetrads of Aleuas. Pelopidas’ death during the battle assured continuous regional civil war. In the late summer of 358 BCE, Alexander II of Pherae's death opened a path for Philip’s diplomatic conquest of Thessaly at the request of Cineas of Larissa. The civil war in Thessaly lasted for six years until Philip’s intervention put an end to it.
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His name consisted of four syllables successively uttered, of four, four, ten, and twelve letters respectively. It might appear as if we were to understand as the first of these the word ἀρχή; and this name of four syllables and thirty letters seems to correspond to a description of the system of thirty Aeons divided into two Tetrads, a Decad, and a Dodecad. Each letter is one of the Aeons, and contains within itself an infinity of mysteries. Each letter makes its own sound, it knows not the sound of the adjacent letter, nor of the whole, but the restitution of all things will take place when all the letters are brought to make the same sound, and then a harmony will result of which we have an image in that made when we all sound the Amen together.
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Although C is considered zero in this example, this is not always the case. For example, a piece (whether tonal or atonal) with a clear pitch center of F might be most usefully analyzed with F set to zero (in which case {0,1,2} would represent F, F and G. (For the use of numbers to represent notes, see pitch class.) Though set theorists usually consider sets of equal-tempered pitch classes, it is possible to consider sets of pitches, non-equal-tempered pitch classes, rhythmic onsets, or "beat classes" (; ). Two-element sets are called dyads, three-element sets trichords (occasionally "triads", though this is easily confused with the traditional meaning of the word triad). Sets of higher cardinalities are called tetrachords (or tetrads), pentachords (or pentads), hexachords (or hexads), heptachords (heptads or, sometimes, mixing Latin and Greek roots, "septachords"—e.g.
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The evidence of plant evolution changes dramatically in the Ordovician with the first extensive appearance of spores in the fossil record (Cambrian spores have been found, also). The first terrestrial plants were probably in the form of tiny plants resembling liverworts when, around the Middle Ordovician, evidence for the beginning of the terrestrialization of the land is found in the form of tetrads of spores with resistant polymers in their outer walls. These early plants did not have conducting tissues, severely limiting their size. They were, in effect, tied to wet terrestrial environments by their inability to conduct water, like extant liverworts, hornworts, and mosses, although they reproduced with spores, important dispersal units that have hard protective outer coatings, allowing for their preservation in the fossil record, in addition to protecting the future offspring against the desiccating environment of life on land.
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These changes are related to the peculiar cohesion occurring in tetrads of the holocentric homologous chromosomes during meiosis that impose obstacles to the releases of chromosomes involved in multiple crossing over events. In the holocentric chromosomes of C. elegans female meiosis, this problem is circumvented restricting crossing over to form only a single chiasma per bivalent and triggering the redistribution of kinetochore proteins along the bivalent axis forming meiosis-specific cup-like structures that uniformly coat each half bivalent but are excluded from the midbivalent region. During anaphase I, C. elegans homologous chromosomes are segregated to the poles by microtubule pushing from the midbivalent regions towards the poles. Differently to what reported in C. elegans, other organisms with holocentric chromosomes, including both plants and insects, circumvent this problem segregating sister chromatids during meiosis I leading to the term inverted meiosis in which the order of reductional and equational division is inverted in respect to canonical meiosis.
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