Search results for "Absolute"

showing 10 items of 518 documents

Determination of U-Pb ages of zircons by direct measurement of the 210Pb/206Pb ratio

1993

Abstract Precise measurements of the 210Pb/206Pb ratio in zircons permits, for the first time, the determination of complete U-Pb ages by measurement of Pb isotopes only, without determination of the U-Pb ratio by isotope dilution. The 238U daughter isotope 210Pb is generally in radioactive equilibrium with 238U; however, the very short half-life of 210Pb (22.3a) results in extremely low 210Pb/206Pb ratios of ∼ 10−8, especially for Archaean zircons. These ratios have been determined using a Finnigan MAT 262® mass spectrometer equipped with a high abundance sensitivity lens system (RPQ). The accuracy of the 210Pb method has been tested on nine different zircon samples with 207Pb/206Pb ages f…

IsotopeGeochemistry and PetrologyAbsolute datingAnalytical chemistryGeologyIsotope dilutionDecay productMass spectrometryGeologyZirconChemical Geology
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Who Persistently Creates Jobs? Absolute versus Relative High-Growth Firms

2017

This paper examines the economic contribution of high-growth firms after their high-growth event. While the central role of high-growth firms for job creation is well-established, little is known about their dynamic development in coming periods. We address this question for the first time by comparing absolute with relative growth measures and use data on private firms in Bulgaria for three consecutive 3-year periods (2001-2004, 2004-2007, and 2007-2010). Next to calculating transition probability matrices to investigate growth in employees in coming periods, we model future employment growth by means of a two-part model with separate equations for the probability of survival and exit as w…

Job creationAggregate growthAbsolute (philosophy)Employment growthEconomicsEconometricsRelative termEconomic contributionPublic supportEvent (probability theory)SSRN Electronic Journal
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The Myth of French Influence Over Spanish Codification: The General Part of the Criminal Codes of 1822 and 1848

2018

The chapter aims to explore the scope of the foreign influences, that of the French in particular, in the criminal codes of 1822 and 1848/50. In doing so, the author departs from the views of some 19th century criminal lawyers who, like J. F. Pacheco, stated that in the old criminal laws “nothing was worthy of respect, or conservation” and “there was only one legitimate and viable system, the system of codification, the system of absolute change,” and recognizing that drafters were fully acquainted with the case of France, a jurisdiction that managed to turn its old laws—including the criminal ones—into modern codes (1804–1811). The author briefly presents the status quaestionis of the dich…

JurisdictionScope (project management)NothingPolitical scienceLawCriminal lawAbsolute ChangeMythology
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NOAA-AVHRR Orbital Drift Correction: Validating Methods Using MSG-SEVIRI Data as a Benchmark Dataset

2021

National Oceanic and Atmospheric Administration–Advanced Very High Resolution Radiometer (NOAA-AVHRR) data provides the possibility to build the longest Land Surface Temperature (LST) dataset to date, starting in 1981 up to the present. However, due to the orbital drift of the NOAA platforms, no LST dataset is available before 2000 and the arrival of newer platforms. Although numerous methods have been developed to correct this orbital drift effect on the LST, a lack of validation has prevented their application. This is the gap we bridge here by using the 15 min temporal resolution of Meteosat Second Generation–Spinning Enhanced Visible and Infra-Red Imager (MSG-SEVIRI) data to simulate dr…

LSTRadiometer010504 meteorology & atmospheric sciencesSeries (mathematics)ScienceQLST; temperature; time series; homogenizationhomogenization0211 other engineering and technologiesSolar zenith angletemperatureAbsolute value02 engineering and technology01 natural sciencesStandard deviationTemporal resolutionGeneral Earth and Planetary SciencesEnvironmental scienceNoise (video)time seriesImage resolution021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensingRemote Sensing
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Assessment of Five Monazite Reference Materials for U-Th/Pb Dating Using Laser-Ablation ICP-MS

2019

Monazite is a common accessory phosphate mineral that occurs under a wide range of pressure and temperature conditions in sedimentary, metamorphic and igneous rocks. Monazite contains high amounts of Th and U, rendering single monazite grains suitable for in-situ U-Th/Pb dating using laser ablation inductively-coupled mass spectrometry (LA-ICP-MS). Two key aspects of monazite dating that are critical for accurate age data with maximum precision are (i) optimized instrumental conditions to minimize analytical scatter and (ii) a well characterized reference material to ensure the accuracy of the obtained aged. Here, we analyzed five monazite reference materials (USGS 44069, 94-222, MAdel, Moa…

Laser ablation010504 meteorology & atmospheric sciencesMAdel94-222U-Th/Pb datinglcsh:QE1-996.5Mineralogy010502 geochemistry & geophysics01 natural sciencesTMMlcsh:GeologyMoacirUSGS 44069La icp msAbsolute datingMonaziteCalibrationmonaziteGeneral Earth and Planetary SciencesLA-ICP-MSInductively coupled plasma mass spectrometryGeologyreference material0105 earth and related environmental sciencesGeosciences
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ChemInform Abstract: Lasiolactols A and B Produced by the Grapevine Fungal Pathogen Lasiodiplodia mediterranea

2016

A strain of Lasiodiplodia mediterranea, a fungus associated with grapevine decline in Sicily, produced several metabolites in liquid medium. Two new dimeric γ-lactols, lasiolactols A and B (1 and 2), were characterized as (2S*,3S*,4R*,5R*,2'S*,3'S*,4'R*,5'R*)- and (2R*,3S*,4R*,5R*,2'R*,3'S*,4'R*,5'R*)-(5-(4-hydroxymethyl-3,5-dimethyl-tetrahydro-furan-2-yloxy)-2,4-dimethyl-tetrahydro-furan-3-yl]-methanols by IR, 1D- and 2D-NMR, and HR-ESI-MS. Other four metabolites were identified as botryosphaeriodiplodin, (5R)-5-hydroxylasiodiplodin, (-)-(1R,2R)-jasmonic acid, and (-)-(3S,4R,5R)-4-hydroxymethyl-3,5-dimethyldihydro-2-furanone (3 - 6, resp.). The absolute configuration (R) at hydroxylated se…

Lasiodiplodia mediterraneabiologyStrain (chemistry)ChemistryToxicityAbsolute configurationGeneral MedicineFungusLiquid mediumFungal pathogenbiology.organism_classificationIn vitroMicrobiologyChemInform
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A new tuning parameter selector in lasso regression

2019

Penalized regression models are popularly used in high-dimensional data analysis to carry out variable selction and model fitting simultaneously. Whereas success has been widely reported in literature, their performance largely depend on the tuning parameter that balances the trade-off between model fitting and sparsity. In this work we introduce a new tuning parameter selction criterion based on the maximization of the signal-to-noise ratio. To prove its effectiveness we applied it to a real data on prostate cancer disease.

Least absolute shrinkage and selection operator (lasso) Model selection Variable selection Penalized likelihood Signal-to-noise ratio Clinical data
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Everywhere differentiability of viscosity solutions to a class of Aronsson's equations

2017

For any open set $\Omega\subset\mathbb R^n$ and $n\ge 2$, we establish everywhere differentiability of viscosity solutions to the Aronsson equation $$ =0 \quad \rm in\ \ \Omega, $$ where $H$ is given by $$H(x,\,p)==\sum_{i,\,j=1}^na^{ij}(x)p_i p_j,\ x\in\Omega, \ p\in\mathbb R^n, $$ and $A=(a^{ij}(x))\in C^{1,1}(\bar\Omega,\mathbb R^{n\times n})$ is uniformly elliptic. This extends an earlier theorem by Evans and Smart \cite{es11a} on infinity harmonic functions.

Lebesgue integration01 natural scienceseverywhere differentiabilityMatrix (mathematics)symbols.namesakeMathematics - Analysis of PDEsL∞-variational problemFOS: MathematicsPoint (geometry)Differentiable function0101 mathematicsAronsson's equationCoefficient matrixMathematical PhysicsMathematicsabsolute minimizerApplied Mathematics010102 general mathematicsMathematical analysista111Riemannian manifold010101 applied mathematicsHarmonic functionMetric (mathematics)symbolsAnalysisAnalysis of PDEs (math.AP)
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Stereoselective Total Synthesis and Absolute Configuration of the Natural Decanolides (−)-Microcarpalide and (+)-Lethaloxin. Identity of (+)-Lethalox…

2005

[reaction: see text] Convergent, stereoselective syntheses of the pharmacologically active, naturally occurring lactones (-)-microcarpalide and (+)-lethaloxin have been achieved from the commercially available, chiral reagents (R)-glycidol, (S,S)-tartaric acid, and d-ribose as the starting materials. These syntheses have further served to establish the hitherto unknown absolute configuration of (+)-lethaloxin and to show its identity with (+)-pinolidoxin.

LethaloxinChemistryStereochemistryOrganic ChemistryMolecular ConformationAbsolute configurationTotal synthesisStereoisomerismAlkenesKetonesPinolidoxinHeterocyclic Compounds 1-RingIdentity (mathematics)AlkanesStereoselectivityMicrocarpalideThe Journal of Organic Chemistry
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Simetries de mirall en l’ordre intern de les construccions absolutes: del català antic al català actual

2016

Resum: Se sol assumir que les construccions absolutes manifesten les mateixes propietats sintàctiques i interpretatives que les subordinades adverbials però, en contrast amb aquestes, no disposen d’un subordinant explícit. En aquest article argumentarem en contra d’aquesta idea. Partint de l’anàlisi de la dislocació del subjecte en el català primitiu i en l’actual, justificarem que les CA encapçalades per una vegada i un cop en català tenen un subordinant format composicionalment per dues porcions discontinues: d’una banda, una preposició incorporada en l’estructura sublèxica del participi, seguint la proposta de Gallego & Hernanz (2012) i, de l’altra, una expressió temporal (una vegada, un…

Linguistics and LanguagePure mathematicsUNESCO::CIENCIAS DE LAS ARTES Y LAS LETRASLingüísticaFilologíasconstrucció absoluta; ordre de paraules; perifèria esquerra; tòpic; gramaticalització; subordinació adverbialLanguage and Linguisticslanguage.human_languageAbsolute (philosophy)Homogeneous space:CIENCIAS DE LAS ARTES Y LAS LETRAS [UNESCO]languageOrder (group theory)CatalanMathematics
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