Search results for "liquid"

showing 10 items of 4351 documents

New fitting scheme to obtain effective potential from Car-Parrinello molecular dynamics simulations: Application to silica

2008

A fitting scheme is proposed to obtain effective potentials from Car-Parrinello molecular dynamics (CPMD) simulations. It is used to parameterize a new pair potential for silica. MD simulations with this new potential are done to determine structural and dynamic properties and to compare these properties to those obtained from CPMD and a MD simulation using the so-called BKS potential. The new potential reproduces accurately the liquid structure generated by the CPMD trajectories, the experimental activation energies for the self-diffusion constants and the experimental density of amorphous silica. Also lattice parameters and elastic constants of alpha-quartz are well-reproduced, showing th…

Car–Parrinello molecular dynamicsMaterials sciencemolecular dynamics calculations (Car-Parrinello) and other numerical simulationsTransferabilityGeneral Physics and AstronomyFOS: Physical sciences02 engineering and technologyglasses01 natural sciencesMolecular physicsMolecular dynamicsLattice (order)0103 physical sciences[PHYS.COND.CM-DS-NN]Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn]010306 general physicsdensity functional theoryCondensed Matter - Materials Sciencegradient and other correctionsMaterials Science (cond-mat.mtrl-sci)Disordered Systems and Neural Networks (cond-mat.dis-nn)computer simulation of liquid structureCondensed Matter - Disordered Systems and Neural Networks021001 nanoscience & nanotechnologylocal density approximation[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Amorphous silica0210 nano-technologyPair potential
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Tannin analysis of chestnut bark samples (Castanea sativa Mill.) by HPLC-DAD-MS.

2014

In the present investigation, an HPLC-DAD/ESI-MS method for the complete analysis of tannins and other phenolic compounds of different commercial chestnut bark samples was developed. A total of seven compounds (vescalin, castalin, gallic acid, vescalagin, 1-O-galloyl castalagin, castalagin and ellagic acid) were separated and quantified, being 1-O-galloyl castalagin tentatively identified and found for the first time in chestnut bark samples. Thus, this method provided information regarding the composition and quality of chestnut bark samples, which is required since these samples are commercialised due to their biochemical properties as ingredients of food supplements.

CastalinFagaceaeMass SpectrometryAnalytical Chemistrychemistry.chemical_compoundPhenolsEllagitanninsBotanyTanninNutsGallic acidFood scienceChromatography High Pressure Liquidchemistry.chemical_classificationPlant ExtractsGeneral MedicineChestnut barkchemistryvisual_artvisual_art.visual_art_mediumComposition (visual arts)BarkHplc dad msTanninsFood ScienceEllagic acidCastalaginFood chemistry
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ORGANIC-INORGANIC HYBRID CATALYSTS BASED ON IMIDAZOLIUM AND THIAZOLIUM SALTS

In the last years, great attention was focused on immobilized ionic liquids for their application in the field of catalysis. The main challenge is represented by the possibility of combining the benefits of the ionic liquids to that of the supports. In order to achieve this ambitious objective both the choice of the support and the functionalization strategy are of fundamental importance. In this context, one of the aims of this doctoral project was to develop novel catalysts based on covalently mono- or multilayer imidazolium or thiazolium networks onto a high ordered mesoporous silica or carbon nanotubes materials. The second goal of this PhD thesis was to design novel imidazolium based c…

Catalysis ionic liquids organic-inorganic hybrid materials palladium nanoparticles POSS single walled carbon nanotubes conversion of carbon dioxide Suzuki reactions.Settore CHIM/06 - Chimica Organica
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Nucleation and cavitation in parahydrogen

2012

We have used a density functional approach to investigate thermal homogeneous nucleation and cavitation in parahydrogen. The effect of electrons as seeds of heterogeneous cavitation in liquid parahydrogen is also discussed within the capillary model. (C) 2011 Elsevier B.V. All rights reserved.

CavitationMetastable phasesChemistryCapillary actionPhysics::Medical PhysicsNucleationGeneral Physics and AstronomyElectronPhysics::Classical PhysicsSpin isomers of hydrogenPhysics::Fluid DynamicsPhysics::Plasma PhysicsHomogeneousChemical physicsCavitationThermalPhysics::Atomic and Molecular ClustersNucleationPhysical chemistryPhysical and Theoretical ChemistryLiquid parahydrogen
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Study of the cytotoxic activity of beauvericin and fusaproliferin and bioavailability in vitro on Caco-2 cells.

2010

Abstract Beauvericin (BEA) is a cyclohexadepsipeptide mycotoxin which has insecticidal properties and produces cytotoxic effects in mammalian cells. Fusaproliferin (FUS) is a mycotoxin that has toxic activity against brine shrimp, insect cells, and teratogenic effects on chicken embryos. The aim of this study was to determine the cytotoxicity of BEA and FUS in human epithelial colorectal adenocarcinoma HT-29 and Caco-2 cells, the transepithelial transport and the bioavailability using Caco-2 cells as a simulated in vitro gastrointestinal model of the human intestinal epithelium. The inhibitory concentration (IC 50 ) evidenced by BEA in the Caco-2 cells was 24.6 and 12.7 μM at 24 and 48 h ex…

Cell SurvivalTerpenesBiological AvailabilityGeneral MedicinePharmacologyBiologyToxicologyIntestinal epitheliumIn vitroBeauvericinBioavailabilitychemistry.chemical_compoundInhibitory Concentration 50chemistryCaco-2DepsipeptidesCytotoxic T cellHumansCaco-2 CellsDrug Screening Assays AntitumorCytotoxicityMycotoxinFood ScienceChromatography LiquidFood and chemical toxicology : an international journal published for the British Industrial Biological Research Association
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Synthesis of insulin and its effects in Y79 human retinoblastoma cells

1994

This paper demonstrates that Y79 human retinoblastoma cells contain immunoreactive insulin (IRI) and release it in the medium. Cells cultured either in suspension or in monolayer showed a similar content of IRI. Moreover, in both conditions, IRI concentration was higher in cells cultured in serum-supplemented medium rather than in serum-free medium. Retinoblastoma cells are capable of synthesizing insulin. This was demonstrated by incubating Y79 cells with [3H]leucine. The synthesized radioactive insulin was separated and assayed by means of a HPLC procedure described in this paper. Both cell growth and [3H]thymidine and [3H]uridine incorporation into acid-insoluble fraction was reduced (-7…

Cell divisionmedicine.medical_treatmentBiologyCellular and Molecular Neurosciencechemistry.chemical_compoundLeucinemedicineTumor Cells CulturedHumansInsulinRNA NeoplasmCycloheximideInsulin-Like Growth Factor IChromatography High Pressure LiquidCell growthInsulinGrowth factorEye NeoplasmsRetinoblastomaDNA Neoplasmretinoblastoma cellsSensory SystemsUridineIn vitroOphthalmologychemistryBiochemistryCell cultureThymidineCell Division
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Antitumor effects of curcumin and structurally β-diketone modified analogs on multidrug resistant cancer cells

2007

Abstract Using concepts of bioisostery a series of curcumin analogs were synthesized: the diketonic system of the compound was elaborated into enaminones, oximes, and the isoxazole heterocycle. The cell growth inhibitory and apoptosis inducing effects of the new analogs were evaluated by in vitro assays in the hepatocellular carcinoma HA22T/VGH cells, as well as in the MCF-7 breast cancer cell line and in its multidrug resistant (MDR) variant MCF-7R. Increased antitumor activity on all cell lines was found with the isoxazole analog and especially with the benzyl oxime derivative; in the HA22T/VGH cell model, the latter compound inhibited constitutive NF-κB activation.

Cell growth inhibitionSpectrometry Mass Electrospray IonizationCurcuminMagnetic Resonance SpectroscopyMDR breast cancer cellsClinical BiochemistryPharmaceutical ScienceAntineoplastic AgentsBiochemistrychemistry.chemical_compoundCell Line TumorDrug DiscoveryNF-κB inhibitionHumansIsoxazoleCytotoxicityMolecular BiologyChromatography High Pressure LiquidCell growthOrganic ChemistryCell growth inhibition; Curcumin oxime derivatives; MDR breast cancer cells; NF-κB inhibition;KetonesCurcumin oxime derivativesDrug Resistance MultipleMultiple drug resistancechemistryBiochemistryDrug Resistance NeoplasmCell cultureApoptosisCancer cellSettore BIO/14 - FarmacologiaCurcuminMolecular MedicineCellBioorganic & Medicinal Chemistry Letters
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Physical activity specifically evokes release of cell-free DNA from granulocytes thereby affecting liquid biopsy

2022

Clinical epigenetics 14, 29 (2022). doi:10.1186/s13148-022-01245-3

Cell typeMyeloidLymphocyteBisulfite sequencing610 Medizin796 Athletic and outdoor sports and games570 Life sciences610 Medical sciencesmedicineGeneticsHumansLiquid biopsyExerciseMolecular BiologyGenetics (clinical)Acute leukemia796 Sportbusiness.industryLiquid BiopsyMethylationDNA Methylationmedicine.anatomical_structureCell-free fetal DNAImmunologybusinessCell-Free Nucleic AcidsGranulocytes570 BiowissenschaftenDevelopmental Biology
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Importance of the liquid to solid weight ratio in the powdered solid-liquid reactions Example drawn from cement constituent hydration

1997

Abstract It seems justified to wonder if the chemical processes which have been evidenced from diluted stirred suspensions are or are not in accordance with those involved in a stagnant paste. The present paper is aimed at clarifying this question which is in connection with the problem of the so called ‘dormant period’ or ‘induction period’ at the beginning of the hydration of Portland cement.

CementChemistryInduction periodMineralogyGeneral ChemistryCondensed Matter PhysicsSuspension (chemistry)law.inventionPortland cementChemical reaction kineticsChemical engineeringlawSpecific surface areaGeneral Materials ScienceSolid liquidSolid State Ionics
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Mating-induced differential peptidomics of neuropeptides and protein hormones in Agrotis ipsilon moths

2018

International audience; In many insects, mating induces drastic changes in male and female responses to sex pheromones or host-plant odors. In the male moth Agrotis ipsilon, mating induces a transient inhibition of behavioral and neuronal responses to the female sex pheromone. As neuropeptides and peptide hormones regulate most behavioral processes, we hypothesize that they could be involved in this mating-dependent olfactory plasticity. Here we used next-generation RNA sequencing and a combination of liquid chromatography, matrix assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, and direct tissue profiling to analyze the transcriptome and peptidome of diffe…

Central Nervous SystemMaleProteomics0301 basic medicinePeptide HormonesCentral nervous systemNeuropeptideAgrotis ipsilonOlfactionsex pheromoneMothsPeptide hormoneBiochemistryTranscriptomeSexual Behavior Animal03 medical and health sciencesSex Factors0302 clinical medicinemedicineAnimalsAgrotis ipsilonmothtransciptomeChromatography High Pressure Liquidreproductive and urinary physiologypeptide predictionmass spectrometrybiology[SDV.BA]Life Sciences [q-bio]/Animal biologyneuropeptidesHigh-Throughput Nucleotide SequencingGeneral Chemistrybiology.organism_classificationCell biologymating030104 developmental biologymedicine.anatomical_structureSpectrometry Mass Matrix-Assisted Laser Desorption-IonizationSex pheromoneplasticityPheromoneFemalePeptides030217 neurology & neurosurgeryolfaction
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