Search results for "call"

showing 10 items of 2320 documents

On (n-l)-wise and joint independence and normality of n Random variables: an example

1981

An example is given of a vector of n random variables such that any (n-1)-dimensional subvector consists of n-1 independent standard normal variables. The whole vector however is neither independent nor normal.

Statistics and ProbabilityPairwise independenceCombinatoricsExchangeable random variablesIndependent and identically distributed random variablesStandard normal deviateMultivariate random variableSum of normally distributed random variablesStatisticsMarginal distributionCentral limit theoremMathematicsCommunications in Statistics - Theory and Methods
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Non-parametric Estimation of the Death Rate in Branching Diffusions

2002

We consider finite systems of diffusing particles in R with branching and immigration. Branching of particles occurs at position dependent rate. Under ergodicity assumptions, we estimate the position-dependent branching rate based on the observation of the particle process over a time interval [0, t]. Asymptotics are taken as t → ∞. We introduce a kernel-type procedure and discuss its asymptotic properties with the help of the local time for the particle configuration. We compute the minimax rate of convergence in squared-error loss over a range of Holder classes and show that our estimator is asymptotically optimal.

Statistics and ProbabilityParticle systemAsymptotically optimal algorithmRate of convergenceErgodicityCalculusEstimatorApplied mathematicsStatistics Probability and UncertaintyMinimaxPoint processMathematicsBranching processScandinavian Journal of Statistics
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Existence, uniqueness and Malliavin differentiability of Lévy-driven BSDEs with locally Lipschitz driver

2019

We investigate conditions for solvability and Malliavin differentiability of backward stochastic differential equations driven by a L\'evy process. In particular, we are interested in generators which satisfy a locally Lipschitz condition in the $Z$ and $U$ variable. This includes settings of linear, quadratic and exponential growths in those variables. Extending an idea of Cheridito and Nam to the jump setting and applying comparison theorems for L\'evy-driven BSDEs, we show existence, uniqueness, boundedness and Malliavin differentiability of a solution. The pivotal assumption to obtain these results is a boundedness condition on the terminal value $\xi$ and its Malliavin derivative $D\xi…

Statistics and Probabilitymatematiikkalocally Lipschitz generatormalliavin differentiability of BSDEsMalliavin-laskentaexistence and uniqueness of solutions to BSDEsBSDEs with jumpsLipschitz continuityLévy processArticleStochastic differential equationMathematics::ProbabilityModeling and Simulationquadratic BSDEsApplied mathematics60H10UniquenessDifferentiable functiondifferentiaaliyhtälötMathematics - Probabilitystokastiset prosessitMathematics
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Biological activity studies on organotin(IV)n+ complexes and parent compounds

2006

This review summarized the literature and own data on the parent organotin(IV) compounds and complexes formed with biologically active ligands.

StereochemistryChemistryOrganic Chemistrycomplexebiologically active ligandbiological activityBiological activityGeneral MedicineBiochemistryInorganic Chemistryanticancer activityorganotin(IV) cationMaterials ChemistryOrganic chemistryPhysical and Theoretical ChemistryJournal of Organometallic Chemistry
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Impact of the use of sterically congested Ir(III) complexes on the performance of light-emitting electrochemical cells

2018

International audience; The synthesis, structural and optoelectronic characterization of a family of sterically congested cyclometalated cationic Ir(iii) complexes of the form [Ir(C^N)2(dtBubpy)]PF6 (with dtBubpy = 4,4′-di-tert-butyl-2,2′-bipyridine and C^N = a cyclometalating ligand decorated at the 4-position of the pyridine ring and/or the 3-position of the phenyl ring with a range of sterically bulky substituents) are reported. This family of complexes is compared to the unsubstituted analogue complex R1 bearing 2-phenylpyridinato as cyclometalating ligand. The impact of sterically bulky substituents on the C^N ligands on both the solid state photophysics and light-emitting electrochemi…

Steric effectsPhotoluminescenceMaterials scienceSterically congested02 engineering and technology010402 general chemistryRing (chemistry)Ligands01 natural sciencesElectrochemical cellchemistry.chemical_compoundPyridineMaterials ChemistryOptoelectronic characterization[CHIM.COOR]Chemical Sciences/Coordination chemistryLight-emitting electrochemical cell[PHYS]Physics [physics]X ray powder diffractionLigandChelationYellow luminescenceCationic polymerizationDevice performancePhotoluminescence quantum yieldsGeneral Chemistry021001 nanoscience & nanotechnology0104 chemical sciencesCyclometalating ligandCrystallographychemistrySynthesis (chemical)Iridium compounds0210 nano-technologyLuminescence[CHIM.OTHE]Chemical Sciences/OtherInternuclear distances
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Zur Stereochemie der Oxidation chiraler, tertiärer Phosphine mit Dimethylsulfoxid

1976

Es wird uber den sterischen Verlauf der Oxidation der optisch aktiven, tertiaren Phosphine 3 and 4 mit Dimethylsulfoxid berichtet. Diese Umsetzung verlauft nur in Gegenwart elektrophiler Katalysatoren (Tabelle 1). Je nach Art and Menge des Katalysators zeigt die Stereochemie der Reaktion entweder uberwiegende Inversion oder Retention der Konfiguration am Phosphor an (Tabellen 2, 3); in einigen Fallen wird jedoch fast vollstandige Racemisierung beobachtet (Tabelle3). Auf der Grundlage dieser stereochemischen Resultate werden mogliche Mechanismen fur diese Umsetzung diskutiert. The Sterochemistry of the Oxidation of Chiral Tertiary Phosphines by Means of Dimethyl Sulfoxide The steric course o…

Steric effectsReaction mechanismDimethyl sulfoxideStereochemistryOrganic ChemistryOptically activeCatalysislaw.inventionchemistry.chemical_compoundchemistrylawElectrophilePhysical and Theoretical ChemistryWalden inversionPhosphineJustus Liebigs Annalen der Chemie
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Synthesis, crystal and molecular-electronic structure, and kinetic investigation of two new sterically hindered isomeric forms of the dimethyl[methyl…

2017

Two new structural isomers – 2,4-dimethyl-5-[methyl(phenylsulfonyl)amino]benzenesulfonyl chloride (1) and 2,4-dimethyl-3-[methyl(phenylsulfonyl)amino]benzenesulfonyl chloride (2) were synthesized by interaction of N-(2,4-dimethylphenyl)-N-methyl-benzenesulfonamide or N-(2,6-dimethylphenyl)-N-methylbenzenesulfonamide with chlorosulfonic acid. Both compounds have been structurally characterized by X-ray single crystal diffraction at 100 K. The crystals of 1 are triclinic: space group View the MathML source, a = 8.1542(2), b = 11.0728(3), c = 11.2680(3) Å, α = 116.557(3), β = 95.155(2), γ = 108.258(2)°, V = 831.97(4) Å3, Z = 2, R = 0.0251 for 2429 reflections; the crystals of 2 are monoclinic:…

Steric effectsSubstitution reaction010405 organic chemistryStereochemistryHydrogen bondOrganic ChemistryTriclinic crystal system010402 general chemistry01 natural sciencesKinetics of substitution reactions in aqueous solution0104 chemical sciencesAnalytical ChemistryInorganic ChemistryCrystallographychemistry.chemical_compoundQuantum-chemical analysischemistryX-ray crystal structure determinationIntramolecular forceBenzenesulfonyl chlorideStructural isomerMoleculeOrtho-effectSterically hindered derivatives of aromatic sulfonic acidsSpectroscopyJournal of Molecular Structure
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The reaction of optically active α-aminocarboxylic acid hydrazides with triethyl orthoesters

2011

New derivatives of 2-(1-amino-1-phenylmethyl)-1,3,4-oxadiazole and 1,2,4-triazin-6-one were synthesised in the reactions of optically active α-aminocarboxylic acid hydrazides and triethyl orthoesters in xylene. The electronic and steric effects of substituents at the α position influencing the formation of five- or six-membered products are discussed.

Steric effectschemistry.chemical_compoundchemistryOrganic ChemistryDrug DiscoveryXyleneOptically activeBiochemistryMedicinal chemistryTetrahedron
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Physics of the nuclear pore complex: Theory, modeling and experiment

2021

Abstract The hallmark of eukaryotic cells is the nucleus that contains the genome, enclosed by a physical barrier known as the nuclear envelope (NE). On the one hand, this compartmentalization endows the eukaryotic cells with high regulatory complexity and flexibility. On the other hand, it poses a tremendous logistic and energetic problem of transporting millions of molecules per second across the nuclear envelope, to facilitate their biological function in all compartments of the cell. Therefore, eukaryotes have evolved a molecular “nanomachine” known as the Nuclear Pore Complex (NPC). Embedded in the nuclear envelope, NPCs control and regulate all the bi-directional transport between the…

Stochastic transportMolecular modelingGeneral Physics and AstronomyComputational biologyMolecular dynamics01 natural sciencesGenomeArticleDiffusionNanochannels0103 physical sciencesotorhinolaryngologic diseasesmedicineNuclear pore010306 general physicsPhysicsComputational modelIntrinsically disordered proteins010308 nuclear & particles physicsCompartmentalization (psychology)Nuclear pore complexCell nucleusCrowdingmedicine.anatomical_structureCytoplasmMultivalencyBiomimeticNucleusFunction (biology)Physics Reports
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Effects of elevated ozone on physiological, anatomical and ultrastructural characteristics of four common urban tree species in China

2016

Fast urbanization has led to ozone (O3) being the main pollutant in summer in most of China. To assess future ground-level O3 effects on the service of urban greening species and clarify the underlying mechanism of O3 damage, four common urban greening species, Ailanthus altissima (AA), Fraxinus chinensis(FC), Platanus orientalis (PO) and Robinia pseudoacacia (RP) were exposed to non-filtered air (NF) and to elevated O3 (E-O3) in open-top chambers. E-O3 induced visible injury in all species as well as microscopic alterations such as collapse of the palisade parenchyma cells, callose accumulation, or chloroplast and mitochondrial accelerated senescence. E-O3 significantly reduced light-satur…

Stomatal conductanceAntioxidant010504 meteorology & atmospheric sciencesmedicine.medical_treatmentBOTANICAGeneral Decision Sciences010501 environmental sciencesPhotosynthesis01 natural scienceschemistry.chemical_compoundOzoneBotanymedicineUrban greening speciesPhotosynthesisAntioxidant systemEcology Evolution Behavior and Systematics0105 earth and related environmental sciencesBIOLOGIA VEGETALAilanthus altissimaEcologybiologyPlatanus orientalisRobiniaRuBisCOCallose15. Life on landbiology.organism_classificationchemistryUltrastructure13. Climate actionbiology.proteinEcological Indicators
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