Search results for "gate"

showing 10 items of 1811 documents

Exponential and bayesian conjugate families: Review and extensions

1997

The notion of a conjugate family of distributions plays a very important role in the Bayesian approach to parametric inference. One of the main features of such a family is that it is closed under sampling, but a conjugate family often provides prior distributions which are tractable in various other respects. This paper is concerned with the properties of conjugate families for exponential family models. Special attention is given to the class of natural exponential families having a quadratic variance function, for which the theory is particularly fruitful. Several classes of conjugate families have been considered in the literature and here we describe some of their most interesting feat…

Statistics and ProbabilityMathematical optimizationClass (set theory)Exponential familyQuadratic equationBayesian probabilityApplied mathematicsStatistics Probability and UncertaintyBayesian inferenceExponential functionConjugateVariance functionMathematicsTest
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Quantum Ring in a Magnetic Field: High Harmonic Generation and NOT Logic Gate

2020

The effect of a static magnetic field on the high harmonic generation (HHG) from a quantum ring driven by one laser polarized along the x-axis is studied. The spin polarization (Formula presented.) and the temporal emission of the harmonics are studied by varying the intensity of the magnetic field and it is shown how these results have a significant technological impact in computer technology; in fact a boolean algebra can be implemented by assigning 0 and 1 values to low and high pulse intensities of the emitted harmonics and logic gates like the NOT can be created.

Statistics and ProbabilityPhysicsNumerical AnalysisRing (mathematics)Multidisciplinaryhigh harmonic generationquantum computingMagnetic fieldModeling and SimulationQuantum mechanicsLogic gatelogic gatesHigh harmonic generationnanoringsQuantumQuantum computerAdvanced Theory and Simulations
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Powerful short-cuts for multiple testing procedures with special reference to gatekeeping strategies.

2007

In this paper we present a general testing principle for a class of multiple testing problems based on weighted hypotheses. Under moderate conditions, this principle leads to powerful consonant multiple testing procedures. Furthermore, short-cut versions can be derived, which simplify substantially the implementation and interpretation of the related test procedures. It is shown that many well-known multiple test procedures turn out to be special cases of this general principle. Important examples include gatekeeping procedures, which are often applied in clinical trials when primary and secondary objectives are investigated, and multiple test procedures based on hypotheses which are comple…

Statistics and ProbabilityResearch designClass (computer programming)Clinical Trials as TopicGatekeepingInterpretation (logic)Models StatisticalEpidemiologybusiness.industryTest proceduresMachine learningcomputer.software_genreGatekeepingEuropesymbols.namesakeBonferroni correctionResearch DesignMultiple comparisons problemsymbolsHumansArtificial intelligencebusinessAlgorithmcomputerMathematicsStatistics in medicine
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A novel digital control for DC/DC converters to improve steady-state performances

2006

This paper describes an innovative digital PWM control implementation for low voltage, high current DC-DC converters. The proposed technique, based on the use of a low resolution DAC, improves steady-state performances, minimizing limit cycle effects. The novel technique is tested on a FPGA-based single phase buck converter operating at 250 kHz. A detailed description of the proposed architecture is given and test results, simulation and experimental ones, are shown

Steady state (electronics)Computer scienceBuck converterLimit cycleElectronic engineeringDigital controlConvertersField-programmable gate arrayLow voltagePulse-width modulationINTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference
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Synthesis and structure-activity relationship studies of cytotoxic cinnamic alcohol derivatives.

2011

Three series of di- and trisubstituted derivatives of cinnamic alcohol and its conjugated dienol analogues were designed and synthesised. The derivatives were screened for cytotoxicity against nine tumour cell lines: KB, A549, Hela, CNE, PC-3, BEL-7404, HL-60, BGC823 and P388D1. Most of the cinnamic alcohol derivatives showed cytotoxic activity. The compound 7-(4',5'-dichlorobenzyloxy)-6,8-dihydroxycinnamic alcohol (55) exhibited significant cytotoxicity to seven human tumour cell lines on a micromolar range, especially with regard to the KB and P388D1 cell lines, showing IC(50) values of 0.4 and 0.5 µM, respectively. The structure-activity relationships of the derivatives are discussed.

StereochemistryCell SurvivalPropanolsAlcoholAntineoplastic AgentsHL-60 CellsPlant ScienceConjugated systemBiochemistryAnalytical ChemistryHeLachemistry.chemical_compoundStructure-Activity RelationshipCell Line TumorStructure–activity relationshipCytotoxic T cellHumansCytotoxicityCinnamyl alcoholbiologyChemistryOrganic Chemistrybiology.organism_classificationCell cultureDrug Screening Assays AntitumorHeLa CellsNatural product research
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Book Review: Non-Benzenoid Conjugated Carbocyclic Compounds. By D. Lloyd

1985

StereochemistryChemistryGeneral MedicineGeneral ChemistryConjugated systemCatalysisAngewandte Chemie International Edition in English
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Oligo(2,5-thienyleneethynylene)s with Terminal Donor-Acceptor Substitution

2006

Five oligo(2,5-thienyleneethynylene) series (OTE, n = 1–5), namely the push-pull substituted compounds 1b-5b and 1c-5c, the purely donor substituted compounds 1a-5a and two precursor series with protected and deprotected ethynyl end-groups, respectively, were obtained by a convergent synthetic strategy. The extension of the conjugated chromophores in the donor-acceptor OTE (DAOTE) series is superimposed by an intramolecular charge transfer (ICT), which decreases with an increasing number, n, of repeat units. The overall effect is studied by the convergence of the UV/Vis absorption maxima λmax (n) → λ∞ for n → ∞.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

StereochemistryChemistryIntramolecular forceOrganic ChemistryPhysical and Theoretical ChemistryChromophoreAbsorption (chemistry)Conjugated systemDonor acceptorEuropean Journal of Organic Chemistry
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[68Ga]Ga-DO2A-(OBu-l-tyr)2: Synthesis, 68Ga-radiolabeling and in vitro studies of a novel 68Ga-DO2A-tyrosine conjugate as potential tumor tracer for …

2009

The synthesis, (68)Ga-labeling and in vitro study of the novel tyrosine chelate derivative [(68)Ga]Ga-1,4,7,10-tetraazacyclododecane-1,7-diacetic acid-4,10-di-(O-butyl)-l-tyrosine ([(68)Ga]Ga-DO(2)A-(OBu-l-tyr)(2)) as a potential tracer for imaging tumor metabolism by positron emission tomography (PET) is presented. This approach combines the biological amino acid transporter targeting properties of l-tyrosine with the outstanding availability of (68)Ga(III) via the (68)Ge/(68)Ga generator. In vitro studies utilizing the F98-glioblastoma cell line revealed specific uptake of [(68)Ga]Ga-DO2A-(OBu-l-tyr)(2) that was comparable to that of the reference O-(2-[(18)F]fluoroethyl)-l-tyrosine (FET)…

StereochemistryClinical BiochemistryPharmaceutical ScienceBiochemistryChemical synthesisCell Line TumorDrug DiscoveryOrganometallic CompoundsAnimalsChelationAmino acid transporterTyrosineMolecular BiologyGallium IsotopesFluoroethylBrain NeoplasmsChemistryOrganic ChemistryLigand (biochemistry)In vitroRatsPositron-Emission TomographyMolecular MedicineRadiopharmaceuticalsGlioblastomaConjugateBioorganic & Medicinal Chemistry Letters
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Star-shaped conjugated compounds forming nematic discotic systems

2004

Abstract Star-shaped compounds, having a benzene ( 9a,b ) or a 1,3,5-triazine ( 11a,b ) core and stilbenoid arms were prepared. Hexyloxy chains, attached in the middle of the arms, provide nematic discotic phases ND, which are unusual for such systems. The position of the sidechains prevents the micro-segregation, which is valid for star-shaped discs of columnar phases. The stilbenoid character of 9a,b and 11a,b guarantees a high light sensitivity. Apart from the statistical CC bond formation by irradiation in solution or in the LC phases, a topochemically controlled chemo-, regio- and stereoselective photocyclodimerization 11a → 12 was found in the crystalline state. The structure determin…

StereochemistryDiscotic liquid crystalOrganic ChemistryConjugated systemStar (graph theory)StilbenoidBiochemistrychemistry.chemical_compoundCrystallographychemistryLiquid crystalDrug DiscoveryStereoselectivityBenzeneTwo-dimensional nuclear magnetic resonance spectroscopyTetrahedron
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Long-range substituent and temperature effect on prototropic tautomerism in 2-(acylmethyl)quinolines

2001

Tautomeric equilibria between 2-(cinnamoylmethyl)quinoline, (Z)-1,2-dihydro-2-(cinnamoylmethylene)quinoline and (Z)-4-phenyl-1-(2-quinolyl)-1,3-butadien-2-ol were studied by 1H, 13C and 15N NMR methods. The —CHCH— fragment conjugated with phenyl and a strong electron donor p-(1-pyrrolidine) substituent were found to favour the enolimine tautomer. This undergoes fast exchange (on the NMR time-scale) with the enaminone form. The amount of the latter tautomer was found to increase at low temperatures. Copyright © 2001 John Wiley & Sons, Ltd.

StereochemistryHydrogen bondOrganic ChemistryQuinolineSubstituentElectron donorCarbon-13 NMRConjugated systemMedicinal chemistryTautomerchemistry.chemical_compoundchemistryProton NMRPhysical and Theoretical ChemistryJournal of Physical Organic Chemistry
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