Search results for "Measurement"

showing 10 items of 2918 documents

Comparative imaging of structure and metabolites in tumours.

1991

A novel technique for metabolic imaging using quantitative bioluminescence and single photon imaging was used to measure the distribution of ATP and lactate in two types of human melanoma xenografts with different radiobiologically hypoxic cell fractions (MF: 45 +/- 17% and EE: 6 +/- 3%; mean +/- SD). The tumours were s.c. grown in nude mice and were used for measurement at volumes of 153-3072 mm3. For metabolic imaging the rapidly frozen tumours were serially sectioned, and each cryosection was brought into contact with a frozen bioluminescent enzyme cocktail using a specially designed glass sandwich system. After thawing section and cocktail the luminescence was started, and light was emi…

Pathologymedicine.medical_specialtyMetaboliteTransplantation HeterologousMice NudeBiologychemistry.chemical_compoundMiceAdenosine TriphosphatemedicineBioluminescenceAnimalsHumansRadiology Nuclear Medicine and imagingRadiosensitivityMelanomachemistry.chemical_classificationMice Inbred BALB CRadiological and Ultrasound Technologymedicine.diagnostic_testMelanomaMetabolismmedicine.diseaseMolecular biologyPhoton countingEnzymechemistryPositron emission tomographyLuminescent MeasurementsLactatesInternational journal of radiation biology
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Benign — A typical nevi discrimination using diffuse reflectance and fluorescence multispectral imaging system

2015

Early diagnostics of skin cancer is of interest for dermatologists. Atypical nevi are not considered to be malignant, but are suspects that should be detected and monitored over time. The multispectral imaging system Nuance operating in spectral range 450–950 nm was adapted for clinical in vivo measurements in diffuse reflectance and fluorescence mode. Mean and standard deviation values of optical density and fluorescence intensity were extracted from segmented pigmented lesions (21 benign and 26 atypical nevi) and used for further analysis. It was possible to achieve 62% sensitivity and 67% specificity for discrimination between atypical and benign lesions using averaged fluorescence mean …

Pathologymedicine.medical_specialtyNuclear magnetic resonanceMaterials scienceMultispectral imagemedicineIn vivo measurementsDiffuse reflectionOptical densityFluorescenceAtypical nevusStandard deviationIntensity (physics)2015 International Conference on BioPhotonics (BioPhotonics)
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High sensitivity of free lambda and free kappa light chains for detection of intrathecal immunoglobulin synthesis in cerebrospinal fluid.

2008

Background –  So far, an inflammation of the central nervous system (CNS) is diagnosed by immunoglobulin measurement in cerebrospinal fluid (CSF) and serum as well as by determination of the oligoclonal bands. With the free kappa and lambda light chains, new markers to diagnose intrathecal synthesis are available. Methods –  In addition to routine diagnostic tests and the assessment of standard parameters, free immunoglobulin light chains were measured in the CSF of patients with neurological disorders. Results –  A significant agreement was found between an increase in free kappa light chain CSF serum quotients and results of the currently widely applied method of oligoclonal band measurem…

Pathologymedicine.medical_specialtyOligoclonal bandMultiple SclerosisImmunoglobulin MeasurementImmunoglobulinsImmunoglobulin lambda-ChainsImmunoglobulin light chainImmunoglobulin kappa-ChainsSensitivity and SpecificityImmunoglobulin kappa-ChainsCerebrospinal fluidImmunoglobulin lambda-ChainsAlzheimer DiseasemedicineAnimalsHumansAnalysis of VarianceSheepbiologybusiness.industryMental DisordersReproducibility of ResultsGeneral MedicineNeurologyImmunologybiology.proteinDementiaNeurology (clinical)AntibodyNervous System DiseasesbusinessKappaActa neurologica Scandinavica
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Mapping cyclic stretch in the postpneumonectomy murine lung

2013

In many mammalian species, the removal of one lung [pneumonectomy (PNX)] is associated with the compensatory growth of the remaining lung. To investigate the hypothesis that parenchymal deformation may trigger lung regeneration, we used respiratory-gated micro-computed tomography scanning to create three-dimensional finite-element geometric models of the murine cardiac lobe with cyclic breathing. Models were constructed of respiratory-gated micro-computed tomography scans pre-PNX and 24 h post-PNX. The computational models demonstrated that the maximum stretch ratio map was patchy and heterogeneous, particularly in subpleural, juxta-diaphragmatic, and cephalad regions of the lobe. In these…

Pathologymedicine.medical_specialtyPhysiologymedicine.medical_treatmentCompensatory growth (organ)PneumonectomyMicePhysiology (medical)ParenchymamedicineShear stressAnimalsRegenerationPneumonectomyLungLungChemistryRespirationAnatomyArticlesLobeMice Inbred C57BLmedicine.anatomical_structureBreathingTomographyStress MechanicalLung Volume MeasurementsTomography X-Ray Computed
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Comparison of Histochemical Staining Methods and Correlation with Transient Elastography in Acute Hepatitis.

2014

<b><i>Objective:</i></b> To compare Masson's trichrome (MT), Sirius red (SR) and orcein staining in acute hepatitis (AH) and to correlate them with<b> </b>transient elastography (TE),<b> </b>a noninvasive method to assess hepatic fibrosis. <b><i>Methods:</i></b> We evaluated liver stiffness by TE in a cohort of 34 consecutive patients and assessed MT-, SR- and orcein-stained biopsies using the METAVIR scoring system and digital image analysis (DIA). <b><i>Results:</i></b> MT and SR both showed severe fibrosis (stage III-IV, DIA = 12.7%). Orcein showed absent or mild fibrosis (stage 0-II, DIA = 4.…

Pathologymedicine.medical_specialtyTransient elastographyContext (language use)Elastic fibrosiSettore MED/08 - Anatomia PatologicaPathology and Forensic Medicinechemistry.chemical_compoundFibrosisTrichromemedicineLiver stiffness measurementStaining methodMolecular BiologyOrceinSirius RedSettore MED/12 - Gastroenterologiabusiness.industryDigital image analysiCell BiologyGeneral Medicinemedicine.diseaseStainingchemistryOrcein stainingTransient elastographyHepatic fibrosisbusinessAcute hepatitiPathobiology : journal of immunopathology, molecular and cellular biology
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Quantification of PCR products by phosphate measurement

2008

Various techniques for quantification of PCR are available. Most frequently, the densitometric intensities of ethidium bromide-stained PCR products separated in gels are compared after normalizing to the levels of housekeeping gene products such as beta-actin. More precise, but extremely time consuming, is the technique of competitive PCR. Newer methods, such as tracking amplification in real-time, have high start-up and maintenance costs (e.g., TaqMan, Applied Biosystems; LightCycler, Roche; I-Cycler, Bio-Rad). Here, I describe an alternative, simple technique to quantify PCR products by determining the entire phosphate released during PCR. The method can be performed using common laborato…

Pcr cloningBiophysicsCell BiologyBiologyPolymerase Chain ReactionSensitivity and SpecificityBiochemistryPhosphate measurementCompetitive pcrPhosphatesHousekeeping geneMiceReal-time polymerase chain reactionBiochemistryEthidiumPrimer dimerGene expressionTaqManAnimalsMolecular BiologyCells CulturedDNA PrimersAnalytical Biochemistry
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Recent Exploits of the ISOLTRAP Mass Spectrometer

2013

Abstract The Penning-trap mass spectrometer ISOLTRAP, located at the isotope-separator facility ISOLDE (CERN), is presented in its current form taking into account technical developments since 2007. Three areas of developments are presented. The reference ion sources have been modified to guarantee a sufficient supply of reference ions for mass measurements and systematic studies. Different excitation schemes have been investigated for manipulation of the ion motion in the Penning trap, to enhance either the purification or measurement process. A multi-reflection time-of-flight mass separator has been implemented and can now be routinely used for purification and as a versatile tool for bea…

Penning-trap mass spectrometryNuclear and High Energy PhysicsLarge Hadron ColliderIon beam analysisChemistry010401 analytical chemistryMeasurement of pure ion ensembles[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]Mass spectrometryPenning trap01 natural sciencesISOLTRAPMulti-reflection time-of-flight mass separator0104 chemical sciencesSecondary ion mass spectrometryNuclear physicsIon-beam analysis0103 physical sciencesBeam purificationIon trapAtomic physics010306 general physicsNuclear ExperimentInstrumentationHybrid mass spectrometer
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Measuring Perceived Severity of Intimate Partner Violence against Women (IPVAW) among the General Population and IPVAW Offenders

2022

ABSTRACT Public perceptions of the severity of intimate partner violence against women (IPVAW) incidents are an important factor that has been linked to key issues regarding this type of violence, such as acceptability or tolerance, personal sense of responsibility, attitudes toward intervention, and the public's, professionals', and victims' responses to IPVAW. The aim of the present study was to provide further validity evidence for the perceived severity of IPVAW scale (PS-IPVAW), by assessing its measurement invariance between gender and age groups, and between men from the general population and male IPVAW offenders. Item response theory was also used to assess the discrimination of th…

Perceived severitySocial PsychologyIntimate partner violence offendersDevelopmental and Educational PsychologyIntimate partner violence against womenItem response theoryApplied PsychologyMeasurement invariancePsychosocial Intervention
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Adaptation and Psychometric Properties of the Scale of Positive and Negative Experience (SPANE) in the General Colombian Population

2021

(1) Background: Diener’s Scale of Positive and Negative Experiences (SPANE) assesses the presence and intensity of positive and negative affects, since these are considered basic aspects of the study of well-being. This article studies its psychometric properties in the general Colombian population. (2) We conducted a cross-sectional study of a sample of 1255 Colombians and we used structural equation modeling to confirm the bifactor structure. Additionally, we studied invariance by gender, and convergent and concurrent validity. (3) We found acceptable fit indicators for the bifactor model (CFI = 0.889, RMSEA = 0.046, SRMR = 0.059) as well as for the convergent (CFI = 0.909, RMSEA = 0.050,…

Percentilepositive and negative experiencesconfirmatory factor analysisPsychometricsHealth Toxicology and MutagenesisConcurrent validity050109 social psychologyColombiaColombian populationpsychological assessmentpsycho-metric propertiesstructural equation modelingStructural equation modelingArticlewellbeing0504 sociologySurveys and Questionnaires0501 psychology and cognitive sciencesPsychological testingMeasurement invarianceComportament col·lectiu05 social sciencesPublic Health Environmental and Occupational HealthR050401 social sciences methodsReproducibility of ResultsConfirmatory factor analysismeasurement invarianceCross-Sectional Studiesquality of lifePsicologiaScale (social sciences)SPANEMedicineMetric (unit)PsychologyFactor Analysis StatisticalPsicometriaClinical psychology
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Determinants of performance drivers in online food delivery platforms: a dynamic performance management perspective

2022

PurposeThis study aims to demonstrate that the Dynamic Performance Management (DPM) framework, integrating performance management with system dynamics modelling, enables decision-makers to identify sustainable strategies in online food delivery platforms, thereby avoiding company failure.Design/methodology/approachThis study undertakes a multistep methodological approach. After the literature review, a retrospective case study approach was used. To build the DPM framework and the system dynamics simulation model, primary and secondary data were collected and analysed.FindingsThis study by adopting the DPM perspective highlights the critical role performance drivers play to assess the viabil…

Performance managementDynamic performance managementSystem dynamics modellingSettore SECS-P/07 - Economia AziendalePerformance driverStrategy and ManagementPerformance measurementOnline food delivery platformGeneral Business Management and AccountingInternational Journal of Productivity and Performance Management
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