Search results for " sample"

showing 10 items of 456 documents

Thermomineral waters of Greece: geochemical characterization

2020

75 °C). In terms of pH most results vary from 5.5 to 823 °C) ii) warm (23 40 °C) iii) thermal (40 75 °C) and iv) hyperthermal (&gtfew springs show either very low pH (&lt10) proposing serpentinization processes. Regarding TDS concentrations collected waters can be subdivided into low salinity (up to 1.5 g/L) brackish (up to 20 g/L) and saline (up to 43 g/L). The medium high salinities can be justified by mixing with sea water and/or strong waterrock interaction processes. Isotope composition of O and H ranges from 12.7 to +2.7 ‰ SMOW and from 91 to +12 ‰ SMOW respectively and is generally comprised between the Global Meteoric Water Line and the East Mediterranean Meteoric Water Line. Only few water samples show a positive shift for δ18O possibly related to high temperature waterrock interaction processes. Carbon dioxide (18 997000 μmol/mol) or N2 (1100 989000 μmol/mol) or CH4 (&ltMany geothermal areas of Greece are located in regions affected by Miocene or Quaternary volcanism and in continental basins characterised by elevated heat flow. Moreover the majority of them is found along the coast as well as in islands of the Aegean Sea and thus thermal water is often brackish to saline due to marine intrusion into costal aquifer. In the present study almost 300 thermal and cold mineral water samples were collected along the Hellenic territory with their physicochemical parameters (temperature pH electrical conductivity and Eh) and the amount of bicarbonates (titration with 0.1N HCl) being determined in situ. Additionally gases found either in free or dissolved phase were sampled. Both water and gas samples were analysed at the INGVPa laboratories for major ions (Ion Chromatography) silica (Inductively Coupled Plasma Optical Emission Spectrometry) chemical composition of free and dissolved gases (Gas Chromatography) water isotopes (O and H) and carbon and helium isotopes of free and dissolved gases (Mass Spectrometry). The temperature of the investigated waters ranges from 6.5 to 98°C pH from 1.96 to 11.98 whilst Total Dissolved Solids (TDS) from 0.06 to 43 g/L. Based on the temperature parameter waters can be divided into four groups: i) cold (&lt0.5 913000 μmol/mol) are the prevailing gas species found in the studied sites. The δ13CCO2 values ranged from 20.1 to +8.5 ‰ whilst the isotope ratio of He from 0.21 to 6.71 R/RA.4) suggesting interaction with H2Srich gases or very high pH values (&gtSettore GEO/08 - Geochimica E Vulcanologia
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Field rules and bias in random surveys with quota samples : an assessment of CIS surveys

2018

Surveys applying quota sampling in their final step are widely used in opinion and market research all over the world. This is also the case in Spain, where the surveys carried out by CIS (a public institution for sociological research supported by the government) have become a point of reference. The rules used by CIS to select individuals within quotas, however, could be improved as they lead to biases in age distributions. Analysing more than 545,000 responses collected in the 220 monthly barometers conducted between 1997 and 2016 by CIS, we compare the empirical distributions of the barometers with the expected distributions from the sample design and/or target populations. Among other …

:62 Statistics [Classificació AMS]Fieldwork rulesQuota samplingInter-quota distributions:Matemàtiques i estadística::Estadística matemàtica [Àrees temàtiques de la UPC]Age and gender groups62D05Centre for Sociological Research quota sampling fieldwork rules age and gender groups inter-quota distributions intra-quota distributionsCentre for sociological research:62 Statistics::62D05 Sampling theory sample surveys [Classificació AMS]Intra-quota distributions
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Stable isotopes covering 96-7 ka BP from stalagmite CM (Santo Tomas Cave, Cuba)

2020

We present a new speleothem trace element and stable isotope record, which extends previous paleoclimate evidence from Cuban speleothems to the last 96 ka. Stable isotope samples were micromilled at a resolution of 0.10-0.33mm, and measured using an IRMS equipped with a Gasbench. Line scans of Element/Calcium ratios of the speleothem were measured by laser ablation ICPMS and were reduced to the resolution of the stable isotope records.

AGESpeleothem sampleδ13C stackedδ13CEarth System Researchpaleoclimatologyδ18O stackedstackedCentral Americaδ18OMass spectrometer DeltaPlusXL coupled to a Gasbench IIspeleothemStable isotopes
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Use of the modified quick easy cheap effective rugged and safe sample preparation approach for the simultaneous analysis of type A- and B-trichothece…

2010

A suitable extraction and purification method for the simultaneous liquid chromatography-mass spectrometry (LC-MS) determination of five mycotoxins, three type A, diacetoxyscirpenol (DAS), T-2 toxin (T-2) and HT-2 toxin (HT-2), and two type B-trichothecenes, deoxynivalenol (DON) and nivalenol (NIV), has been optimised using a modified "Quick Easy Cheap Effective Rugged and Safe" (QuEChERS) method. Different solvents were studied in the extraction procedure to obtain better recoveries, which ranged from 86 to 108%, using a 85/15 (v/v) mixture of methanol/acetonitrile. The values obtained for recovery, repeatability and reproducibility of the optimized method are in agreement with Commission …

AcetonitrilesChromatographyChemistryMethanolFlourOrganic ChemistryExtraction (chemistry)Wheat flourAnalytic Sample Preparation MethodsGeneral MedicineRepeatabilityQuechersBiochemistryMass SpectrometryDiacetoxyscirpenolAnalytical Chemistrychemistry.chemical_compoundVomitoxinLiquid chromatography–mass spectrometrySolventsSample preparationTrichothecenesTriticumChromatography LiquidJournal of Chromatography A
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A new principle to normalize plasma concentrations allowing single-sample clearance determinations in both children and adults.

1992

A sufficiently accurate quantification of renal function requiring only one plasma sample without an additional gamma-camera study has, until now, only been possible in adults. A new principle will be presented here allowing the universal application of known algorithms, regardless of the clearance substance used, by normalizing the plasma concentrations with respect to the individual body dimensions of the patients - for infants as well as for adults. In this respect, algorithms are developed for clearance determinations using technetium-99m mercaptoacetyltriglycine (99mTc-MAG3), which are based on steady-state studies as the reference. They allow the calculation of quantitative clearance …

AdultAdolescentRenal functionSingle sampleKidneylaw.inventionRenal CirculationTechnetium Tc 99m MertiatidelawBlood plasmaMedicineHumansRadiology Nuclear Medicine and imagingChildRadionuclide ImagingGamma camerabusiness.industryInfant NewbornInfantGeneral MedicineOrganotechnetium CompoundsStandard errorChild PreschoolPlasma concentrationbusinessNuclear medicineQuantitative analysis (chemistry)OligopeptidesAlgorithmsBlood samplingEuropean journal of nuclear medicine
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Cross-cultural validation of the Mood Questionnaire in three spanish-speaking countries Argentina, Ecuador, and Spain

2020

This study validates the Mood Questionnaire for adults in three Spanishspeaking countries: Argentina, Ecuador, and Spain. It then analyzes the influence of gender and cultural differences on mood, and whether there is a relationship between mood, emotional intelligence, and the Avoidance of Responsibility. A convenience sample of 1048 adults, with a middle-class socioeconomic background, was selected from three Spanish-speaking countries (Spain, Argentina, and Ecuador). The psychometric properties of the Mood Questionnaire are adequate, which is particularly interesting given the need for transcultural tools to evaluate moods. Moreover, the mood was associated with avoidance of responsibili…

AdultCross-Cultural ComparisonMaleAdolescentPsychometricsSocial PsychologyArgentina050109 social psychologyConvenience sampleSpanish speakingbehavioral disciplines and activities050105 experimental psychologyCIENCIAS SOCIALESYoung AdultEMOTIONAL INTELLIGENCESurveys and QuestionnairesCultural diversitymental disordersHumansCross-cultural0501 psychology and cognitive sciencesSocioeconomic statusSpanish-speaking countriesEmotional intelligence05 social sciencesReproducibility of ResultsSpanish versionMiddle AgedPsicologíaMoodSpainMOODFemaleEcuadorCROSS-CULTURAL VALIDATIONPsychologyAVOIDANCE OF RESPONSIBILITYClinical psychology
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Development and testing of a model for risk and protective factors for eating disorders and higher weight among emerging adults: A study protocol

2019

Research has demonstrated that eating disorders (ED) and higher weight have lifetime co-occurrence suggesting that they may be best considered within a common etiological model. Although we know that body dissatisfaction is likely to be a risk factor for both outcomes, other proposed risk and protective factors for each condition have not been adequately explored. The current paper tests a conceptual model that is based on a review of the existing literature from both areas of scholarship. It considers biological, sociocultural, psychological, and behavioral factors that may contribute to both outcomes. The model will be tested in a longitudinal design with an initial sample of 600 emerging…

AdultCross-Cultural ComparisonMaleGerontologyBiopsychosocial model050103 clinical psychologyAdolescentSocial PsychologyInitial sample050109 social psychologySettore M-PSI/08 - PSICOLOGIA CLINICAHigher weightFeeding and Eating DisordersYoung AdultSurveys and QuestionnairesBody ImagemedicineHumansCross-cultural0501 psychology and cognitive sciencesPath analysis (statistics)General PsychologyApplied PsychologyCross-cultural; Eating disorders; Gender; Higher weight; Model; Risk factorsData collectionResearch05 social sciencesEating disorderGenderCross-culturalOverweightProtective Factorsmedicine.diseaseEating disordersRisk factorsEating disordersEtiologyFemalePsychologyBody dissatisfactionModel
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De la encuesta a la base de datos: experiencia de trabajo de campo del estudio «Inmigración, trabajo y salud» (Proyecto ITSAL)

2011

Objective: Despite the need for information in the area of migration and health, the available data are sparse. We describe the field work in a cross-sectional study on the health of immigrant workers in Spain. Method: A convenience sample of workers from Colombia, Ecuador, Morocco and Rumania in four cities was targeted, using a block-walking approach. The outcome rates of the American Association of Public Opinion Research were estimated. Results: Of 6,504 persons approached, 71.4% were eligible contacts. Of these contacts, only 57.8% completed interviews. Response and cooperation rates were above 50%. Conclusions: Block-walking enabled surveyors to access difficult-to-reach groups. The u…

AdultEmploymentMaleTrabajadores inmigrantesDatabases FactualUrban Populationmedia_common.quotation_subjectImmigrationEmigrants and ImmigrantsConvenience sampleTarget populationColombiaPublic opinionMigrant workersField (computer science)Sampling StudiesYoung AdultEnvironmental healthSurveys and QuestionnairesMedicineHumansmedia_commonOccupational healthbusiness.industryRomaniaData CollectionCommunication BarriersPublic Health Environmental and Occupational HealthSalud laboralEmigration and ImmigrationHealth SurveysWork experienceMoroccoCross-Sectional StudiesWork (electrical)SpainData collectionHealth surveyTrabajo de campoFemaleField methodsEcuadorbusinessRecogida de datosGaceta Sanitaria
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Definition of the upper reference limit of glycated albumin in blood donors from Italy.

2017

Abstract Background: Glycated Albumin (GA) has been proposed as a short-term indicator of glycemic homeostasis. The aim of this study is to describe the distribution of GA in a large sample of blood donors from Italy to evaluate whether demographic features, namely age and sex, could influence GA levels and define specific reference limits. Methods: The study included 1334 Italian blood donors. GA was measured using an enzymatic method (quantILab Glycated Albumin, IL Werfen, Germany). The upper reference limit (URL) was calculated using the non-parametric percentile method. Results: A modest, although significant, increase of GA was observed in relation to age (p<0.001), especially in ma…

AdultGlycation End Products AdvancedMalemedicine.medical_specialtyPercentileAdolescentClinical BiochemistryPopulationSerum albuminEnzyme Assay030209 endocrinology & metabolismBlood Donors030204 cardiovascular system & hematology03 medical and health sciencesYoung Adult0302 clinical medicineGlycated albuminReference ValuesInternal medicineDiabetes mellitusmedicineblood donors; diabetes; glycated albumin; reference limit; Adolescent; Adult; Aged; Enzyme Assays; Female; Humans; Italy; Male; Middle Aged; Reference Values; Serum Albumin; Young Adult; Blood Donors; Clinical Biochemistry; Biochemistry (medical)HumansReference ValueGlycated Serum AlbuminYoung adulteducationSerum AlbuminGlycemicAgedEnzyme Assayseducation.field_of_studydiabetesbiologyBlood Donorbusiness.industryBiochemistry (medical)General MedicineMiddle Agedreference limitmedicine.diseaseLarge sampleItalydiabetebiology.proteinglycated albuminFemalebusinessHumanClinical chemistry and laboratory medicine
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Ultra-Performance Liquid Chromatography-Ion Mobility Separation-Quadruple Time-of-Flight MS (UHPLC-IMS-QTOF MS) Metabolomics for Short-Term Biomarker…

2020

A major problem with dietary assessments is their subjective nature. Untargeted metabolomics and new technologies can shed light on this issue and provide a more complete picture of dietary intake by measuring the profile of metabolites in biological samples. Oranges are one of the most consumed fruits in the world, and therefore one of the most studied for their properties. The aim of this work was the application of untargeted metabolomics approach with the novel combination of ion mobility separation coupled to high resolution mass spectrometry (IMS-HRMS) and study the advantages that this technique can bring to the area of dietary biomarker discovery, with the specific case of biomarker…

AdultMale0301 basic medicineCitruslcsh:TX341-641Orange (colour)Diet Surveys01 natural sciencesorange intakeArticleMass SpectrometryEating03 medical and health sciencesMetabolomicsion mobilityIon Mobility SpectrometryHumansBiomarker discoveryChromatography High Pressure LiquidCross-Over Studies030109 nutrition & dieteticsNutrition and DieteticsChromatographyPlasma samplesChemistryDietary intake010401 analytical chemistryfood and beveragesbiomarkersCrossover studyIntervention studiesmetabolomicsHealthy Volunteers0104 chemical sciencesDietary biomarkersFemalelcsh:Nutrition. Foods and food supplyFood Science
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