Search results for "Peat"

showing 10 items of 1026 documents

OCT for Assessing Artificial Tears Effectiveness in Contact Lens Wearers

2011

PURPOSE: To apply a commercially available high-resolution spectral domain optical coherence tomographer (SOCT) to assess the change in tear volume after application of a new artificial tears formulation specifically developed for contact lens (CL) users. METHODS: Twenty OD from young healthy CL wearers (mean age, 24.7 ± 3.5 years) with refractive errors ranging from -0.75 to -2.50 D (mean, -1.56 ± 0.69 D) were examined. All subjects were fitted with Focus Dailies CL (Ciba Vision), and two drops of Blink Contacts (AMO), lubricating formulation specifically developed for CL wearers, were instilled after baseline measures. Tear meniscus volume (TMV) was measured immediately after and 1 min, 1…

Adultmedicine.medical_specialtyContact Lensesmedicine.medical_treatmentMeniscus (anatomy)Tear volumeYoung AdultRegular distributionOphthalmologyImage Processing Computer-AssistedHumansMedicinebusiness.industryRepeated measures designContact Lenses HydrophilicRefractive ErrorsContact lensOphthalmologyArtificial tearsmedicine.anatomical_structureTear meniscusOftalmologíaDry Eye SyndromesEyelidOphthalmic SolutionsbusinessTomography Optical CoherenceFollow-Up StudiesOptometryOptometry and Vision Science
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Towards comprehensive non-target screening using heart-cut two-dimensional liquid chromatography for the analysis of organic atmospheric tracers in i…

2021

Abstract Non-target screening of secondary organic aerosol compounds in ice cores is used to reconstruct atmospheric conditions and sources and is a valuable tool to elucidate the chemical profiles of samples with the aim to obtain as much information as possible from one mass spectrometric measurement. The coupling of mass spectrometry to chromatography limits the results of a non-target screening to signals of compounds within a certain polarity range based on the utilized stationary phases of the columns. Comprehensive two-dimensional liquid chromatography (LCxLC) introduces a second column of different functionality to enable the analysis of a broader range of analytes. Conventional LCx…

AerosolsDetection limitChromatography Reverse-PhaseAnalyteChromatographyChemistryHydrophilic interaction chromatographyOrganic ChemistryGeneral MedicineRepeatabilityMass spectrometrySnowBiochemistryMass SpectrometryAnalytical ChemistryAerosolVolume (thermodynamics)Hydrophobic and Hydrophilic InteractionsChromatography LiquidJournal of Chromatography A
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Longitudinal Study on Sustained Attention to Response Task (SART): Clustering Approach for Mobility and Cognitive Decline

2022

The Sustained Attention to Response Task (SART) is a computer-based go/no-go task to measure neurocognitive function in older adults. However, simplified average features of this complex dataset lead to loss of primary information and fail to express associations between test performance and clinically meaningful outcomes. Here, we combine a novel method to visualise individual trial (raw) information obtained from the SART test in a large population-based study of ageing in Ireland and an automatic clustering technique. We employed a thresholding method, based on the individual trial number of mistakes, to identify poorer SART performances and a fuzzy clusters algorithm to partition the da…

AgingHealth (social science)SART cognition fuzzy clusters mobility decline multimodal visualization repeated measures specificity sustained attention to response task thresholdsustained attention to response task; SART; multimodal visualization; threshold; fuzzy clusters; cognition; repeated measures; mobility decline; specificityGeriatrics and GerontologySettore MAT/07 - Fisica MatematicaGerontologyGeriatrics
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Progerin expression induces a significant downregulation of transcription from human repetitive sequences in iPSC-derived dopaminergic neurons.

2019

Repetitive DNA sequences represent about half of the human genome. They have a central role in human biology, especially neurobiology, but are notoriously difficult to study. The purpose of this study was to quantify the transcription from repetitive sequences in a progerin-expressing cellular model of neuronal aging. Progerin is a nuclear protein causative of the Hutchinson–Gilford progeria syndrome that is also incrementally expressed during the normal aging process. A dedicated pipeline of analysis allowed to quantify transcripts containing repetitive sequences from RNAseq datasets oblivious of their genomic localization, tolerating a sufficient degree of mutational noise, all with low c…

AgingRetroelementsTranscription GeneticAluInduced Pluripotent Stem CellsAlu elementDown-RegulationSettore BIO/11 - Biologia MolecolareRetrotransposonComputational biologyBiologySettore BIO/19 - Microbiologia GeneraleProgerinProgeriaSettore BIO/13 - Biologia ApplicataAlu ElementsRepetitive sequencemedicineRetrotransposonHumansDNA transposonRepeated sequenceGeneCellular SenescenceProgeriaintegumentary systemDopaminergic NeuronsFibroblastsmedicine.diseaseProgerinLamin Type ASettore BIO/18 - GeneticaSatelliteHuman genomeOriginal ArticleGeriatrics and GerontologyGeroScience
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The Significance of Treasure Hunting: Past and Present

2012

It is certainly insufficient to explain treasure hunting as a reaction to poverty or a form of greed and avarice.1 Avarice has been seen as a part of the human condition and thus as a non-historical, that is, a quasi-anthropological constant. Anthropological constants hardly ever help to explain the behaviour of historical people. In our case, an alleged human tendency to accumulate material wealth does not explain why some people engaged in treasure hunting whereas others did not. Why did people look for treasure? Why did they talk about treasure? Why were they willing to suffer the repeated failure of treasure hunts and continue to look for hidden riches?

Agrarian societyHistoryPovertyEarly modern periodRepeated failureEnvironmental ethicsHuman conditionProtestant work ethicTreasureArchaeology
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Isolation and characterization of 8 microsatellite loci for the "killer shrimp'', an invasive Ponto-Caspian amphipod Dikerogammarus villosus (Crustac…

2015

5 pages; International audience; Dikerogammarus villosus is a freshwater amphipod of the Ponto-Caspian origin recognized as one of the 100 worst alien species in Europe, having negative impact on biodiversity and functioning of the invaded aquatic ecosystems. The species has a wide ecophysiological tolerance and during the last 20 years it has rapidly spread throughout European inland waters. In consequence, it presents a major conservation management problem. We describe eight polymorphic microsatellite loci developed for D. villosus by combining a biotin-enrichment protocol and new generation 454GS-FLX Titanium pyrosequencing technology. When genotyped in 64 individuals from two locations…

AmphipodaPopulation geneticsBiodiversityPopulation geneticsIntroduced species[SDV.BID]Life Sciences [q-bio]/BiodiversityBiologyArticleInvasive speciesDikerogammarus villosusPolymorphic lociGene FrequencyGeneticsAnimalsAmphipoda14. Life underwaterBiological invasionsMolecular BiologyAlleles[ SDV.BID ] Life Sciences [q-bio]/Biodiversity[ SDE.BE ] Environmental Sciences/Biodiversity and EcologyPolymorphism GeneticInvasive speciesEcologyDikerogammarus villosus[ SDV.GEN.GA ] Life Sciences [q-bio]/Genetics/Animal geneticsDNAGeneral Medicinebiology.organism_classificationShrimp[SDV.GEN.GA]Life Sciences [q-bio]/Genetics/Animal geneticsGenetic LociMicrosatellite[SDE.BE]Environmental Sciences/Biodiversity and EcologyMicrosatellite Repeats
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Fully Automated Electric-Field-Driven Liquid Phase Microextraction System with Renewable Organic Membrane As a Front End to High Performance Liquid C…

2019

This article reports for the first time a programmable-flow-based mesofluidic platform that accommodates electric-field-driven liquid phase microextraction (μ-EME) in a fully automated mode. The miniaturized system is composed of a computer-controlled microsyringe pump and a multiposition rotary valve for handling aqueous and organic solutions at a low microliter volume and acts as a front-end to online liquid chromatographic separation. The organic membrane is automatically renewed and disposed of in every analytical cycle, thus minimizing analyte carry-over effects while avoiding analyst intervention. The proof-of-concept applicability of the automated mesofluidic device is demonstrated b…

AnalyteAqueous solutionChromatographyChemistry010401 analytical chemistryExtraction (chemistry)Repeatability010402 general chemistry01 natural sciencesHigh-performance liquid chromatography0104 chemical sciencesAnalytical ChemistryMembraneVolume (thermodynamics)Electric fieldAnalytical Chemistry
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Determination of trichothecenes and zearalenones in grain cereal, flour and bread by liquid chromatography tandem mass spectrometry

2012

Although analytical methods have been already reported for legislated mycotoxins as trichothecenes and zearalenone (ZON) separately, we describe the optimization of a simple and rapid multimycotoxin method for the determination of a total of 12 mycotoxins simultaneously, nine trichothecenes (NIV, DON, FUS-X, DAS, 15-AcDON, 3-AcDON, NEO, HT-2, T-2 T2), and zearalenone and its metabolites (ZON, a-ZOL, b-ZOL), of different origin (wheat, oat, barley and spelt) and in three different products where these substance can be present (grain, flour and bread) reach the food chain and cause toxic effect either in humans or animals. The extraction procedure was based on a mixture of acetonitrile/water …

AnalyteAvenaFlourFood ContaminationTandem mass spectrometryMass spectrometryAnalytical Chemistrychemistry.chemical_compoundTandem Mass SpectrometryLiquid chromatography–mass spectrometryMicotossineMycotoxinZearalenoneChromatography High Pressure LiquidTriticumChromatographyMolecular StructureExtraction (chemistry)HordeumBreadGeneral MedicineRepeatabilityMycotoxinschemistryZearalenonesicurezza alimentareEdible GrainTrichothecenesFood Science
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Analytical capabilities of high performance liquid chromatography – Atmospheric pressure photoionization – Orbitrap mass spectrometry (HPLC-APPI-Orbi…

2015

A new analytical method was established and validated for the analysis of 27 brominated flame retardants (BFRs), including so called "emerging" and "novel" BFRs (EBFRs and NBFRs) in fish samples. High performance liquid chromatography (HPLC) coupled to Orbitrap mass spectrometry (Orbitrap-MS) employing atmospheric pressure photoionization (APPI) interface operated in negative mode was used for the identification/quantitation of contaminants. HPLC-Orbitrap-MS analysis provided a fast separation of selected analytes within 14 min, thus demonstrating a high throughput processing of samples. The developed methodology was tested by intralaboratory validation in terms of recovery, repeatability, …

AnalyteChromatographyAtmospheric pressureChemistryAnalytical chemistryRepeatabilityMass spectrometryOrbitrapBiochemistryHigh-performance liquid chromatographyAnalytical Chemistrylaw.inventionPolybrominated diphenyl ethersCertified reference materialslawEnvironmental ChemistrySpectroscopyAnalytica Chimica Acta
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Capillary electrophoretic and extraction conditions for the analysis of Catha edulis FORKS active principles

2013

A capillary electrophoretic method, which allowed the detection and separation of the active principles of Catha edulis, i.e. cathinone, cathine and phenylpropanolamine, was developed. A suitable internal standard (nicotinamide), which permitted the quantification of the analytes reducing the variability of the migration times due to EOF changes, was identified. The analytical method was validated, assessing linearity, sensitivity and repeatability, showing optimal features for the analysis of the vegetable material. Moreover extraction conditions were investigated to achieve the exhaustion of the plant material in the fastest and most efficient way to meet the requirements of the Court.

AnalyteChromatographyMolecular StructureCathinonePlant ExtractsChemistryCapillary actionPhenylpropanolamineExtraction (chemistry)Vegetable materialElectrophoresis CapillaryReproducibility of ResultsCathaRepeatabilityPathology and Forensic MedicineElectrophoresisAlkaloidsSettore MED/43 - Medicina LegaleCathinone Cathine PhenylpropanolaminemedicineLawCathinemedicine.drug
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