Search results for "Function"

showing 10 items of 14432 documents

On the Betti numbers of three fat points in P1 × P1

2019

In these notes we introduce a numerical function which allows us to describe explicitly (and nonrecursively) the Betti numbers, and hence, the Hilbert function of a set Z of three fat points whose support is an almost complete intersection (ACI) in P1 × P1 . A nonrecursively formula for the Betti numbers and the Hilbert function of these configurations is hard to give even for the corresponding set of five points on a special support in P2 and we did not find any kind of this result in the literature. Moreover, we also give a criterion that allows us to characterize the Hilbert functions of these special set of fat points.

13F20Fat points Hilbert functions Multiprojective spaces13A15Fat pointsMathematics - Commutative Algebra13D40Mathematics - Algebraic GeometrySettore MAT/02 - AlgebraFat points; Hilbert functions; Multiprojective spacesMultiprojective spacesSettore MAT/03 - GeometriaMathematics - Algebraic Geometry; Mathematics - Algebraic Geometry; Mathematics - Commutative Algebra; 13F20 13A15 13D40 14M0514M05Hilbert functions
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1,3-Dipolar Cycloaddition Reactions of Indan-1-one Enamines across Arylnitrile Oxides Leading to Novel Cyclic Isoxazoline Derivatives

2013

Synthesis of a series of cyclic fused-isoxazolines has been accomplished by regioselective and diastereoselective 1,3-dipolar cycloaddition of 3-methylindan-1-one enamines (1a, 1b, 1c) and 3-phenylindan-1-one enamines (2a, 2b, 2c) to arylnitrile oxides (3d, 3e, 3f, 3g, 3h). The structure of the cycloadducts was elucidated by 1H and 13C NMR spectroscopy. The proposed regio- and stereochemistry of fused-compounds (4) and (5) has also been corroborated by two single-crystal X-ray diffraction studies carried out on 4-methyl-8b-morpholinyl-3-(p-tolyl)-4H-3a,8b-dihydroindeno[2,3-d]isoxazoline (4be) and 3-(p-anisyl)-4-phenyl-8b-pyrrolidinyl-4H-3a,8b-dihydroindeno[2,3-d]isoxazoline (5af) and by mea…

13c nmr spectroscopy010405 organic chemistryStereochemistryChemistryOrganic Chemistry13-Dipolar cycloadditionRegioselectivityDensity functional theory010402 general chemistry01 natural sciencesMedicinal chemistryCycloaddition0104 chemical sciencesJournal of Heterocyclic Chemistry
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Inégalité de Lojasiewicz en géométrie pfaffienne

2000

We give a Lojasiewicz inequality for the $o$-minimal structure generate by Rolle leaves over the globally subanalytic sets. We obtain uniform estimates in the iterated exponentials scale.

14P15Scale (ratio)Iterated functionMathematics::Complex VariablesGeneral MathematicsStructure (category theory)Applied mathematics32B20Exponential functionMathematics03C64
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Varieties of algebras with pseudoinvolution and polynomial growth

2017

Let A be an associative algebra with pseudoinvolution (Formula presented.) over an algebraically closed field of characteristic zero and let (Formula presented.) be its sequence of (Formula presented.) -codimensions. We shall prove that such a sequence is polynomially bounded if and only if the variety generated by A does not contain five explicitly described algebras with pseudoinvolution. As a consequence, we shall classify the varieties of algebras with pseudoinvolution of almost polynomial growth, i.e. varieties of exponential growth such that any proper subvariety has polynomial growth and, along the way, we shall give also the classification of their subvarieties. Finally, we shall de…

16R50; 16W50; growth; Polynomial identity; Primary: 16R10; pseudoinvolution; Secondary: 16W10Linear function (calculus)PolynomialPure mathematicspseudoinvolutionAlgebra and Number TheorySubvariety16R50growth010102 general mathematicsPolynomial identity pseudo involution codimension growthZero (complex analysis)010103 numerical & computational mathematicsPolynomial identity01 natural sciencesPrimary: 16R10Settore MAT/02 - AlgebraBounded functionAssociative algebra0101 mathematicsAlgebraically closed fieldVariety (universal algebra)16W50Secondary: 16W10MathematicsLinear and Multilinear Algebra
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Towards Quantifying Non-Photosynthetic Vegetation for Agriculture Using Spaceborne Imaging Spectroscopy

2021

Non-photosynthetic vegetation (NPV) has been identified as priority variable in the context of new spaceborne imaging spectroscopy missions. In this study we provide a first attempt to quantify NPV biomass from these unprecedented data streams to be provided by multiple recently launched or planned instruments. A hybrid workflow is proposed including Gaussian process regression (GPR) trained over radiative transfer model (RTM) simulations and applying active learning strategies. A soybean field data set including two dates with NPV measurements on yellow and senescent (brown) plant organs was used for model validation, resulting in relative errors of 13.4%. This prototype retrieval model wa…

2. Zero hunger010504 meteorology & atmospheric sciencesData stream mining0211 other engineering and technologiesEnMAPHyperspectral imagingContext (language use)PRISMA02 engineering and technologyVegetationVegetation functional trait01 natural sciencesLigninImaging spectroscopyAtmospheric radiative transfer codesWorkflowHybrid approacheCHIMEKrigingEnvironmental scienceCelluloseGaussian process regression021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensing
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Effects of Coronavirus Disease 2019 (COVID-19) on Family Functioning

2021

More than a year and a half after the first clinical manifestations of coronavirus disease 2019 (COVID-19) were reported in Wuhan, China,1 , 2 the magnitude of the pandemic across the globe and its related clinical and social effects3 remain unclear.4 The pandemic has affected lives and sparked concerns about everything from health to job security. In high–Gross Domestic Product (GDP) countries, despite trillions in coronavirus aid released by governments, many families still struggle to pay for basic necessities like food and rent, and these difficulties worsened during the pandemic.5 , 6 The general social uncertainty caused by the pandemic seems to have also affected family resilience, w…

2019-20 coronavirus outbreakCoronavirus disease 2019 (COVID-19)Adolescentbusiness.industrySARS-CoV-2Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)Family functioningMEDLINECOVID-19VirologyAdolescent ; Child ; COVID-19 ; Family ; Humans ; Pandemics ; Parent-Child Relations ; Psychosocial Functioning ; SARS-CoV-2ArticlePsychosocial FunctioningPediatrics Perinatology and Child HealthMedicineHumansFamilyParent-Child RelationsbusinessChildPandemics
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Past, Present and Future Perspectives on Halloysite Clay Minerals

2020

Halloysite nanotubes (HNTs), clay minerals belonging to the kaolin groups, are emerging nanomaterials which have attracted the attention of the scientific community due to their interesting features, such as low-cost, availability and biocompatibility. In addition, their large surface area and tubular structure have led to HNTs’ application in different industrial purposes. This review reports a comprehensive overview of the historical background of HNT utilization in the last 20 years. In particular it will focus on the functionalization of the surfaces, both supramolecular and covalent, following applications in several fields, including biomedicine, environmental science and catalysis.

2019-20 coronavirus outbreakCoronavirus disease 2019 (COVID-19)Surface PropertiesSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2)Pharmaceutical ScienceNanotechnologyReviewhalloysite nanotubesengineering.materialHalloysiteAnalytical Chemistrylcsh:QD241-441lcsh:Organic chemistryDrug DiscoveryPhysical and Theoretical ChemistryParticle SizeMineralsMolecular StructureOrganic ChemistrySettore CHIM/06 - Chimica Organicahistorical backgroundsupramolecular functionalizationChemistry (miscellaneous)engineeringMolecular MedicineClayClay mineralschemical modificationMolecules
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The proof of Birman’s conjecture on singular braid monoids

2003

Let B_n be the Artin braid group on n strings with standard generators sigma_1, ..., sigma_{n-1}, and let SB_n be the singular braid monoid with generators sigma_1^{+-1}, ..., sigma_{n-1}^{+-1}, tau_1, ..., tau_{n-1}. The desingularization map is the multiplicative homomorphism eta: SB_n --> Z[B_n] defined by eta(sigma_i^{+-1}) =_i^{+-1} and eta(tau_i) = sigma_i - sigma_i^{-1}, for 1 <= i <= n-1. The purpose of the present paper is to prove Birman's conjecture, namely, that the desingularization map eta is injective.

20F36 57M25. 57M27[ MATH.MATH-GT ] Mathematics [math]/Geometric Topology [math.GT]Monoid[ MATH.MATH-GR ] Mathematics [math]/Group Theory [math.GR]Braid group20F36Group Theory (math.GR)01 natural sciencesBirman's conjecture[MATH.MATH-GR]Mathematics [math]/Group Theory [math.GR]CombinatoricsMathematics - Geometric TopologyMathematics::Group Theory57M25. 57M27Mathematics::Category Theory[MATH.MATH-GT]Mathematics [math]/Geometric Topology [math.GT]FOS: MathematicsBraid0101 mathematics[MATH.MATH-GR] Mathematics [math]/Group Theory [math.GR][MATH.MATH-GT] Mathematics [math]/Geometric Topology [math.GT]MathematicsConjecturedesingularization010102 general mathematicsMultiplicative functionSigmaGeometric Topology (math.GT)singular braidsInjective function010101 applied mathematicsHomomorphismGeometry and TopologyMathematics - Group TheoryGeometry & Topology
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FMapper: Scalable read mapper based on succinct hash index on SunWay TaihuLight

2022

Abstract One of the most important application in bioinformatics is read mapping. With the rapidly increasing number of reads produced by next-generation sequencing (NGS) technology, there is a need for fast and efficient high-throughput read mappers. In this paper, we present FMapper – a highly scalable read mapper on the TaihuLight supercomputer optimized for its fourth-generation ShenWei many-core architecture (SW26010). In order to fully exploit the computational power of the SW26010, we employ dynamic scheduling of tasks, asynchronous I/O and data transfers and implement a vectorized version of the banded Myers algorithm tailored to the 256 bit vector registers of the SW26010. Our perf…

256-bitSpeedupXeonComputer Networks and CommunicationsComputer scienceHash functionParallel computingSW26010SupercomputerTheoretical Computer ScienceArtificial IntelligenceHardware and ArchitectureScalabilitySoftwareSunway TaihuLightJournal of Parallel and Distributed Computing
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The influence of serotonin- and other genes on impulsive behavioral aggression and cognitive impulsivity in children with attention-deficit/hyperacti…

2008

Contains fulltext : 70708.pdf (Publisher’s version ) (Open Access) ABSTRACT: BACKGROUND: Low serotonergic (5-HT) activity correlates with increased impulsive-aggressive behavior, while the opposite association may apply to cognitive impulsiveness. Both types of impulsivity are associated with attention-deficit/hyperactivity disorder (ADHD), and genes of functional significance for the 5-HT system are implicated in this disorder. Here we demonstrate the separation of aggressive and cognitive components of impulsivity from symptom ratings and test their association with 5-HT and functionally related genes using a family-based association test (FBAT-PC). METHODS: Our sample consisted of 1180 o…

2805 Cognitive Neurosciencemedicine.medical_specialtyNeurologyGenetics and epigenetic pathways of disease [NCMLS 6]Cognitive NeuroscienceMedizin610 Medicine & healthNeuroinformatics [DCN 3]SerotonergicImpulsivityMental health [NCEBP 9]lcsh:RC346-429Genomic disorders and inherited multi-system disorders [IGMD 3]03 medical and health sciencesBehavioral Neuroscience0302 clinical medicineCognitive neurosciences [UMCN 3.2]2802 Behavioral NeurosciencePerception and Action [DCN 1]medicineAttention deficit hyperactivity disorderddc:610Medizinische Fakultät » Universitätsklinikum Essen » LVR-Klinikum Essen » Klinik für Psychiatrie Psychosomatik und Psychotherapie des Kindes- und JugendaltersAssociation (psychology)Psychiatrylcsh:Neurology. Diseases of the nervous systemBiological PsychiatryAggressionResearchCognitionGeneral Medicine10058 Department of Child and Adolescent Psychiatrymedicine.disease030227 psychiatryAutism spectrum disordermedicine.symptomPsychologyFunctional Neurogenomics [DCN 2]2803 Biological Psychiatry030217 neurology & neurosurgeryClinical psychology
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