Search results for "VARIATION"

showing 10 items of 2124 documents

A comparative analysis of genetic variation in rootstocks and scions of old olive trees – a window into the history of olive cultivation practices an…

2014

Background Past clonal propagation of olive trees is intimately linked to grafting. However, evidence on grafting in ancient trees is scarce, and not much is known about the source of plant material used for rootstocks. Here, the Simple Sequence Repeat (SSR) marker technique was used to study genetic diversity of rootstocks and scions in ancient olive trees from the Levant and its implications for past cultivation of olives. Leaf samples were collected from tree canopies (scions) and shoots growing from the trunk base (suckers). A total of 310 trees were sampled in 32 groves and analyzed with 14 SSR markers. Results In 82.7% of the trees in which both scion and suckers could be genotyped, t…

HeterozygotePlant ScienceBiologyPlant RootsTreesDomesticationOleaparasitic diseasesGenetic variationBotanySuckerCultivarIsraelMicrosatellitesPropagationAllelesPhylogenyPrincipal Component AnalysisGenetic diversityGraftingGeographyGenetic VariationOlive treesGenetic distanceGenetic LociGenetic markerOlive cultivarsRootstockPlant ShootsResearch ArticleMicrosatellite RepeatsBMC Plant Biology
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Detailed study of the X-ray and optical/UV orbital ephemeris of X1822-371

2011

Recent studies of the optical/UV and X-ray ephemerides of X1822-371 have found some discrepancies in the value of the orbital period derivative. Because of the importance of this value in constraining the system evolution, we comprehensively analyse all the available optical/UV/X eclipse times of this source to investigate the origin of these discrepancies. We collected all previously published X-ray eclipse times from 1977 to 2008, to which we added the eclipse time observed by Suzaku in 2006. This point is very important to cover the time gap between the last RXTE eclipse time (taken in 2003) and the most recent Chandra eclipse time (taken in 2008). Similarly we collected the optical/UV e…

High Energy Astrophysical Phenomena (astro-ph.HE)Physics010308 nuclear & particles physicsAstrophysics::High Energy Astrophysical PhenomenaX-rayFOS: Physical sciencesAstronomy and Astrophysicsneutron X-rays: binaries X-rays: stars stars: individual: X1822-371 [stars]AstrophysicsDerivativeTime gapEphemerisOrbital period01 natural sciencesSettore FIS/05 - Astronomia E AstrofisicaCover (topology)Space and Planetary Sciencestars: neutron X-rays: binaries X-rays: stars stars: individual: X1822-3710103 physical sciencesAstrophysics::Solar and Stellar AstrophysicsAstrophysics::Earth and Planetary AstrophysicsAstrophysics - High Energy Astrophysical PhenomenaVariation (astronomy)010303 astronomy & astrophysicsEclipse
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A variational method for spectral functions

2016

The Generalized Eigenvalue Problem (GEVP) has been used extensively in the past in order to reliably extract energy levels from time-dependent Euclidean correlators calculated in Lattice QCD. We propose a formulation of the GEVP in frequency space. Our approach consists of applying the model-independent Backus-Gilbert method to a set of Euclidean two-point functions with common quantum numbers. A GEVP analysis in frequency space is then applied to a matrix of estimators that allows us, among other things, to obtain particular linear combinations of the initial set of operators that optimally overlap to different local regions in frequency. We apply this method to lattice data from NRQCD. Th…

High Energy Physics - LatticeVariational methodLattice (order)Quantum mechanicsHigh Energy Physics - Lattice (hep-lat)Euclidean geometryLattice field theoryFOS: Physical sciencesEstimatorApplied mathematicsLattice QCDLinear combinationEigendecomposition of a matrixProceedings of 34th annual International Symposium on Lattice Field Theory — PoS(LATTICE2016)
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Diurnal variation of tree pollen in the air in finland

1984

Abstract The pollen was collected with Burkard spore traps in Turku and Jyvaskyla, in southern and central Finland. Selected days of high concentration were analysed for hour to hour concentrations. The diurnal variation of pollen concentration was variable in Alnus, Betula, Juniperus and Pinus, while Picea, Populus, Quercus, Salix and Ulmus had regular daytime maxima och nightly minima. The pollen concentrations were closely correlated with increasing temperatures and decreasing relative humidities. A significant relationship with wind speed was also found, except in Alnuts and Betula. The most significant relationships with wind speed were found in Salix and Quercus, the pollen of which t…

High concentrationDiurnal temperature variationPlant Sciencemedicine.disease_causeWind speedSporePinus <genus>HorticulturePollenBotanymedicineEnvironmental scienceRegular daytimeEcology Evolution Behavior and SystematicsTree pollenGrana
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High resolution analysis and differential condensation in RBA-banded human chromosomes.

1981

Human prophase, premetaphase, and mid-metaphase chromosomes are prepared and analyzed using the thymidine cell synchronization technique and R-banding patterns (RBA). Haploid sets with 700–1000 bands can be demonstrated. Sequences of chromosomes of different degrees of condensation are helpful for a better understanding and classification of regions of extended chromosomes. A considerable variation in the condensation of parts of homologous chromosomes is reflected in the variability of the arm ratio. This differential condensation of chromosomes is entirely effected by variation of the degree of condensation in AT rich interbands and can be attributed to the degree of labeling by BrdU.

High resolution analysisGeneticsCondensationCytological TechniquesGenetic VariationBiologyProphaseAcridine OrangeChromosome BandingProphaseBromodeoxyuridineGeneticsHomologous chromosomeBiophysicsChromosomes HumanHumansPloidyCell synchronizationGenetics (clinical)MetaphaseHuman genetics
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Arousal Styles during Public Speaking

2002

The nature of the public-speaking context as a physiologically arousing communication context is well-known. During public speaking, a significant increase in heart rate level above the baseline has been found in various studies. In these studies, arousal styles during speaking have generally been described on the basis of mean heart rates among a group of participants. Individual variation in HR responses has not received much attention. The purpose of the present study was to examine individual differences in heart rate responses during public speaking and to account for these differences in terms of particular explanatory variables. The heart rate curves of 47 speakers were examined one …

Higher educationbusiness.industryCommunicationContext (language use)Language and LinguisticsEducationDevelopmental psychologyStyle (sociolinguistics)ArousalPublic speakingVariation (linguistics)Heart rateWillingness to communicatebusinessPsychologySocial psychologyCommunication Education
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Basics of doubly heavy tetraquarks

2018

We outline the most important results regarding the stability of doubly heavy tetraquarks $QQ\bar q\bar q$ with an adequate treatment of the four-body dynamics. We consider both color-mixing and spin-dependent effects. Our results are straightforwardly applied to the case of all-heavy tetraquarks $QQ\bar Q\bar Q$. We conclude that the stability is favored in the limit $M_Q/m_q \gg 1$ pointing to the stability of the $bb\bar u\bar d$ state and the instability of all-heavy tetraquarks.

HistoryParticle physics[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th]Nuclear TheoryBar (music)FOS: Physical sciencesspin: dependence01 natural sciencesInstabilityStability (probability)EducationNuclear Theory (nucl-th)High Energy Physics - Phenomenology (hep-ph)0103 physical scienceseffect: colorheavy quarkLimit (mathematics)010306 general physicsNuclear theoryPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyState (functional analysis)stabilitytetraquarkmathematical methods: variationalComputer Science ApplicationsHigh Energy Physics - Phenomenologyfew-body problem[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]TetraquarkHigh Energy Physics::Experiment
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Religious Exiting and Social Networks: Computer Simulations of Religious/Secular Pluralism

2021

Statistical models attempting to predict who will disaffiliate from religions have typically accounted for less than 15% of the variation in religious affiliations, suggesting that we have only a partial understanding of this vital social process. Using agent-based simulations in three “artificial societies” (one predominantly religious; one predominantly secular; and one in between), we demonstrate that worldview pluralism within one’s neighborhood and family social networks can be a significant predictor of religious (dis)affiliation but in pluralistic societies worldview diversity is less important and, instead, people move toward worldview neutrality. Our results suggest that there may …

HistoryReligions. Mythology. RationalismSociology and Political Sciencemedia_common.quotation_subjectReligious studiesBL1-2790Gender StudiesPhilosophySocial supportEarly adopterVariation (linguistics)Pluralism (political theory)AnthropologyVDP::Samfunnsvitenskap: 200NeutralitySociologySociology Computer ScienceSocial psychologyDiversity (politics)media_commonSecularism and Nonreligion
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Introduction

2018

HistoryVariation (linguistics)EconometricsTerm (time)
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The cohomology of a variation of polarized Hodge structures over a quasi-compact Kähler manifold

2007

In this article, we consider the cohomologies with coefficients in a variation of polarized Hodge structures on a quasi-compact Kaehler manifold. We show that the L 2 L^2 -Dolbeault cohomology can be identified with the L 2 L^2 cohomology; we also give several direct applications of the result above.

Hodge conjecturePure mathematicsAlgebra and Number Theoryp-adic Hodge theoryVariation (linguistics)Hodge theoryMathematical analysisDe Rham cohomologyComplex differential formGeometry and TopologyKähler manifoldCohomologyMathematicsJournal of Algebraic Geometry
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