Search results for "Proportion"

showing 10 items of 877 documents

Electrochemical and Spectroelectrochemical Behavior of a Tetracyanotriphenodioxazine in Solution and Thin-Films

2018

International audience; We report the electrochemical behavior of a tetracyano triphenodioxazine bearing two triisopropylsilylethynyl moieties (TiPS‐TPDO‐tetraCN) during its reduction studied either in solution or after vacuum evaporation deposition on indium tin oxide (ITO) support. While in dichloromethane, it typically proceeds in two successive monoelectronic reactions, in acetonitrile, the mechanism appears more complex. Fine analysis of the spectroelectrochemical results combined with simulation of the voltammograms with various amount of water suggest the involvement of water and of a restructured dianion in the electrochemical process. In the solid‐state, the formation of the diprot…

Materials scienceDisproportionation02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyElectrochemistryPhotochemistry01 natural sciencesCatalysis0104 chemical sciencesElectrochemistryProton-coupled electron transferThin film0210 nano-technology[CHIM.OTHE]Chemical Sciences/Other
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Control of catalytic properties of ZSM-5 made by fast and template- free synthesis.

1989

Abstract The fast template-free synthesis of ZSM-5 was accomplished in both static and stirred autoclaves employing sodiumwaterglass.silica hydrogel and pyrogenic silicas as silica sources. Highly pure crystalline ZSM-5 was obtained in the sodiumwaterglass reaction system in the stirred autoclaves without seeds within 3 hours. Addition of 2% (w/w) of seeds reduced the reaction time to 2 hours. The catalytic activity and shape selectivity of the H-ZSM-5, tested by the disproportionation of ethylbenzene, was found to be largely controlled by the synthesis parameters and by the posttreatments. The homogeneous aluminum distribution across the crystals achieved by this synthetis route resulted i…

Materials sciencechemistry.chemical_elementDisproportionationEthylbenzeneCatalysislaw.inventionchemistry.chemical_compoundTemplatechemistryChemical engineeringAluminiumlawOrganic chemistryCalcinationZSM-5Selectivity
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On properties of the iterative maximum likelihood reconstruction method

1989

In this paper, we continue our investigations6 on the iterative maximum likelihood reconstruction method applied to a special class of integral equations of the first kind, where one of the essential assumptions is the positivity of the kernel and the given right-hand side. Equations of this type often occur in connection with the determination of density functions from measured data. There are certain relations between the directed Kullback–Leibler divergence and the iterative maximum likelihood reconstruction method some of which were already observed by other authors. Using these relations, further properties of the iterative scheme are shown and, in particular, a new short and elementar…

Mathematical optimizationIterative proportional fittingIterative methodGeneral MathematicsKernel (statistics)Expectation–maximization algorithmGeneral EngineeringApplied mathematicsIterative reconstructionDivergence (statistics)Integral equationLocal convergenceMathematicsMathematical Methods in the Applied Sciences
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Pegylated liposomal doxorubicin in the management of ovarian cancer

2014

Ovarian cancer is the leading cause of death among gynecological tumors. Carboplatin/paclitaxel represents the cornerstone of front-line treatment. Instead, there is no consensus for management of recurrent/progressive disease, in which pegylated liposomal doxorubicin (PLD) ± carboplatin is widely used. We performed a systematic review and metaanalysis to evaluate impact of PLD-based compared with no-PLD-based regimens in the ovarian cancer treatment. Data were extracted from randomized trials comparing PLD-based treatment to any other regimens in the January 2000-January 2013 time-frame. Study end-points were overall survival (OS), progression free survival (PFS), response rate (RR), CA125…

MetaanalysiOncologyCancer Researchmedicine.medical_specialtyendocrine system diseasesPharmacologyarian cancerDisease-Free SurvivalPolyethylene Glycolslaw.inventionchemistry.chemical_compoundRandomized controlled triallawOvPegylated liposomal doxorubicinInternal medicinemedicineHumansProgression-free survivalSystemic chemotherapyProportional Hazards ModelsRandomized Controlled Trials as TopicOvarian NeoplasmsPharmacologyAntibiotics Antineoplasticbusiness.industryProportional hazards modelHazard ratiomedicine.diseaseCarboplatinTreatment OutcomeOncologychemistryTolerabilityDoxorubicinClinical StudyMolecular MedicineFemaleRandomized clinical trialbusinessOvarian cancerProgressive diseaseCancer Biology & Therapy
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Walnut Consumption, Plasma Metabolomics, and Risk of Type 2 Diabetes and Cardiovascular Disease

2021

BACKGROUND: Walnut consumption is associated with lower risk of type 2 diabetes (T2D) and cardiovascular disease (CVD). However, it is unknown whether plasma metabolites related to walnut consumption are also associated with lower risk of cardiometabolic diseases. OBJECTIVES: The study aimed to identify plasma metabolites associated with walnut consumption and evaluate the prospective associations between the identified profile and risk of T2D and CVD. METHODS: The discovery population included 1833 participants at high cardiovascular risk from the PREvención con DIeta MEDiterránea (PREDIMED) study with available metabolomics data at baseline. The study population included 57% women (baseli…

MetabolitePopulationMedicine (miscellaneous)PhysiologyJuglansType 2 diabetesLower riskchemistry.chemical_compoundMetabolomicsRisk FactorsCarnitinemedicineHumansMetabolomicsNutsGenomics Proteomics and MetabolomicsAmino Acidseducationeducation.field_of_studyNutrition and Dieteticsbusiness.industryProportional hazards modelIncidence (epidemiology)medicine.diseaseLipidsDiabetes Mellitus Type 2chemistryCardiovascular DiseasesPurinesPopulation studybusinessBiomarkersThe Journal of Nutrition
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Les partis politiques et la représentation proportionnelle.

2015

International audience; Depuis l’avènement de la Cinquième République, la revendication en faveur de la représentation proportionnelle (RP) - pour la désignation des députés - a été récurrente, et même quasi-unanime, de la part des formations d’opposition ou minoritaires : la RP apparaît comme la promesse de disposer de positions institutionnelles et de participer – s’agissant des élections législatives – au jeu parlementaire. Même le candidat du parti dominant, Nicolas Sarkozy, admettait en 2007 « la possibilité d'introduire un peu de proportionnelle au Sénat ou à l'Assemblée nationale sans créer le risque d'une instabilité qui serait désastreuse. » Aujourd’hui encore, la plupart des forma…

MinoritésPartis politiquesElections législativesReprésentation proportionnelle[SHS.SCIPO] Humanities and Social Sciences/Political science[SHS.SCIPO]Humanities and Social Sciences/Political sciencePersonnel politiqueMode de scrutin
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Integrated experimental and computational spectroscopy study on the protonation of the α-nitronyl nitroxide radical unit

2011

The stability of the α-nitronyl nitroxide radical unit under acidic conditions is investigated by an integrated experimental UV/Vis spectroscopy and TDDFT study. In the field of molecular magnetism, α-nitronyl nitroxide radicals are important as purely organic spin carriers due to their synthetic versatility. Here, the existence of an intermediate of the protonated α-nitronyl nitroxide radical unit is demonstrated for the first time and a proposed disproportionation reaction is confirmed.

Models MolecularNitroxide mediated radical polymerizationFree RadicalsChemistryMagnetismSpectrum AnalysisRadicalMolecular ConformationGeneral Physics and AstronomyDisproportionationProtonationTime-dependent density functional theoryPhotochemistryCyclic N-OxidesQuantum TheoryProtonsPhysical and Theoretical ChemistrySpectroscopySpin (physics)Phys. Chem. Chem. Phys.
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Isomerization and disproportionation of m-xylene in a zeolite with 9- and 10-membered ring pores: Molecular dynamics and catalytic studies

2006

The unique pore topology of zeolite ITQ-13 with 9-membered ring (MR) channels intersected by perpendicular 10-MR channels and larger void space with 10-MR cross-sections was studied for meta-xylene isomerization and disproportionation. Product distribution was interpreted on the basis of pore topology and compared with zeolites with 12-MR (β), 10-MR, and intersecting 12-MR cavities (NU-87), as well as 10-MR (ZSM-5) zeolites. The presence of cavities allows more space for bulky intermediates and/or products and also provides room for molecules to drive consecutive reactions toward thermodynamic equilibrium. Channels, on the other hand, allow diffusion without trapping if their free diameters…

Molecular dynamicsCrystallographyThermodynamic equilibriumChemistryOrganic chemistryDisproportionationPhysical and Theoretical ChemistryRing (chemistry)Molecular sieveZeoliteIsomerizationCatalysisCatalysisJournal of Catalysis
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253 PFS of elderly ovarian cancer patients might be predicted by G-8 geriatric screening tool – results of a retrospective cohort study

2021

Introduction/Background* The aim of this study was to evaluate the impact of the preoperative global health status on the prognosis of patients with ovarian cancer (OC) older than 60 years, who received cytoreductive surgery. Methodology G-8 geriatric screening tool (G-8 score), Lee Schonberg prognostic index, Eastern Cooperative Oncology Group (ECOG) performance status and Charlson Comorbidity Index (CCI) were determined retrospectively in a consecutive cohort of elderly patients with OC. Univariate and multivariate Cox regression analyses and Kaplan-Meier method were performed to analyze the impact of the preoperative global health status on survival. Result(s)* 116 patients entered the s…

Multivariate statisticsmedicine.medical_specialtyMultivariate analysisPerformance statusbusiness.industryProportional hazards modelUnivariateRetrospective cohort studymedicine.diseaseInternal medicineCohortmedicineOvarian cancerbusinessOvarian cancer
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Prognostic factors of overall survival for patients with FIGO stage IIIc or IVa ovarian cancer treated with neo-adjuvant chemotherapy followed by int…

2020

International audience; Introduction The aim of this study was to identify prognostic factors of overall survival in patients with FIGO stage IIIc or IVa ovarian cancer (OC) treated by neo-adjuvant chemotherapy (NAC) followed by interval debulking surgery.Materials and methods Data from 483 patients with ovarian cancer were retrospectively collected, from January 1, 2000 to December 31, 2016, from the FRANCOGYN database, regrouping data from 11 centers specialized in ovarian cancer treatment. Median overall survival was determined using the Kaplan-Meier method. Univariate and multivariate analysis were performed to define prognostic factors of overall survival.Results The median overall sur…

Neoplasm Residualmedicine.medical_treatmentGenes BRCA2FIGO Stage IIICGenes BRCA1Platinum CompoundsCarcinoma Ovarian EpithelialCohort Studies0302 clinical medicineAscitic FluidOverall survivalPeritoneal Lavage030212 general & internal medicineOvarian NeoplasmsUnivariate analysisCytoreduction Surgical ProceduresGeneral MedicineMiddle AgedPrognosisDebulkingNeoadjuvant Therapy3. Good healthSurvival RateOncology030220 oncology & carcinogenesisFemaleTaxoidsFranceOmentumCohort studymedicine.medical_specialty[SDV.CAN]Life Sciences [q-bio]/CancerAntineoplastic Agents[SDV.MHEP.GEO]Life Sciences [q-bio]/Human health and pathology/Gynecology and obstetricsInterval debulking surgeryNeoadjuvant chemotherapyPelvis03 medical and health sciences[SDV.CAN] Life Sciences [q-bio]/CancerOvarian cancerMedian follow-upmedicineHumansNeoplasm InvasivenessAgedNeoplasm StagingProportional Hazards Modelsbusiness.industryRetrospective cohort studymedicine.diseaseSurgery[SDV.MHEP.GEO] Life Sciences [q-bio]/Human health and pathology/Gynecology and obstetrics[SDV.SPEE] Life Sciences [q-bio]/Santé publique et épidémiologieMultivariate AnalysisLymph Node Excision[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologieSurgeryLymphadenectomyLymph NodesOvarian cancerbusinessEuropean Journal of Surgical Oncology
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