1,787 research outputs found

    DNA methylation-based age prediction and telomere length in white blood cells and cumulus cells of infertile women with normal or poor response to ovarian stimulation.

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    An algorithm assessing the methylation levels of 353 informative CpG sites in the human genome permits accurate prediction of the chronologic age of a subject. Interestingly, when there is discrepancy between the predicted age and chronologic age (age acceleration or AgeAccel ), patients are at risk for morbidity and mortality. Identification of infertile patients at risk for accelerated reproductive senescence may permit preventative action. This study aimed to assess the accuracy of the epigenetic clock concept in reproductive age women undergoing fertility treatment by applying the age prediction algorithm in peripheral (white blood cells [WBCs]) and follicular somatic cells (cumulus cells [CCs]), and to identify whether women with premature reproductive aging (diminished ovarian reserve) were at risk of AgeAccel in their age prediction. Results indicated that the epigenetic algorithm accurately predicts age when applied to WBCs but not to CCs. The age prediction of CCs was substantially younger than chronologic age regardless of the patient\u27s age or response to stimulation. In addition, telomeres of CCs were significantly longer than that of WBCs. Our findings suggest that CCs do not demonstrate changes in methylome-predicted age or telomere-length in association with increasing female age or ovarian response to stimulation

    Real-time phase-shift detection of the surface plasmon resonance

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    We investigate a method to directly measure the phase of a laser beam reflected from a metallic film after excitation of surface plasmon polaritons. This method permits real time access to the phase information, it increases the possible speed of data acquisition, and it may thus prove useful for increasing the sensitivity of surface plasmon based sensors

    Simulation of Near-field Dispersion of Pollutants Using Detached-Eddy Simulation

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    A numerical simulation is developed using the unsteady-state turbulence model on a structured highly refined grid to predict the wind-flow field and dispersion field of a pollutant emitted from a rooftop stack around a two-building configuration. The results obtained are compared with those of a steady-state model previously reported by the authors. The pollutant concentrations are examined on the roof where the stack is located as well as on the leeward wall of an upstream tower to the emitting building in order to evaluate how the pollutant is dispersed by the DES model compared to RNG model. DES results are discussed against those from RNG k–ε approach and wind tunnel. The study emphasises limits in reproducing correctly the wind flow and dispersion fields due to underestimation and/or overestimation of the Reynolds stress components and the steady-state methodology when using the RNG k–ε model. Despite such limits, the RNG model produces a similar average error, in terms of concentrations, to that obtained with the DES model

    Effect of Stack Height and Exhaust Velocity on Pollutant Dispersion in the Wake of a Building

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    The dispersion of pollutants exhausted from a building roof stack located in the wake of a tower is investigated by means of the realizable k–ɛ turbulence model. Variations in stack height and pollutant exhaust velocity are considered to assess their influence on the distribution of pollutant concentrations in the neighbourhood of the emitting building. In order to determine optimum locations for fresh-air intakes, the worst case is considered, namely when the wind originates directly upstream of the tower and places the emitting building in its wake. Special attention is given to the evolution of the plume and distribution of pollutant concentrations on the roof and windward wall of the emitting building, as well as on the leeward wall of the upwind tower. Simulation results are compared to wind tunnel experiments conducted in a boundary layer wind tunnel. For this particular configuration, the paper shows that increasing the stack height has an effect similar to that obtained by increasing the momentum ratio, but with some differences, depending upon which wall of the two buildings is considered. On the emitting building, the leeward wall has the lowest concentration values for all stack heights and momentum ratios considered; thus this is the best location for fresh-air intakes. However, for the tower, fresh-air intakes should not be located on the leeward wall due to high pollutant concentrations. The results show completely different pollutant dispersion patterns from those for an isolated building. This highlights the importance of accounting for structures that lie in close proximity to the emitting building

    Numerical Simulation of Pollutant Dispersion around Building Complex. Building and Environment

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    The dispersion of exhausted pollutants from a building roof stack situated in the wake of a neighbouring tower has been studied using computational fluid dynamics (CFD) with the realizable k–ɛ turbulence model for closure. Two scales are considered in this work, full-scale (1:1) and wind tunnel scale (1:200). Of primary interest are the distributions of the plume and of the pollutant concentrations on the building roof as well as on the leeward wall of the tower. Two stack heights and pollutant exhaust velocities have been considered for the distribution of pollutant concentrations in the neighbourhood of the building from which the pollutant is emitted. Results are compared with measurements from field and wind tunnel experiments to estimate the accuracy of simulations

    Inter-laboratory proficiency testing scheme for tumour next-generation sequencing in Ontario: A pilot study

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    Background A pilot inter-laboratory proficiency scheme for 5 Ontario clinical laboratories testing tumour samples for the Ontario-wide Cancer Targeted Nucleic Acid Evaluation (OCTANE) study was undertaken to assess proficiency in the identification and reporting of next-generation sequencing (NGS) test results in solid tumour testing from archival formalin-fixed, paraffin-embedded (FFPE) tissue. Methods One laboratory served as the reference centre and provided samples to 4 participating laboratories. An analyte-based approach was applied: each participating laboratory received 10 FFPE tissue specimens profiled at the reference centre, with tumour site and histology provided. Laboratories performed testing per their standard NGS tumour test protocols. Items returned for assessment included genes and variants that would be typically reported in routine clinical testing and variant call format (VCF) files to allow for assessment of NGS technical quality. Results Two main aspects were assessed: Technical quality and accuracy of identification of exonic variants Site-specific reporting practices Technical assessment included evaluation of exonic variant identification, quality assessment of the VCF files to evaluate base calling, variant allele frequency, and depth of coverage for all exonic variants. Concordance at 100% was observed from all sites in the technical identification of 98 exonic variants across the 10 cases. Variability between laboratories in the choice of variants considered clinically reportable was significant. Of the 38 variants reported as clinically relevant by at least 1 site, only 3 variants were concordantly reported by all participating centres as clinically relevant. Conclusions Although excellent technical concordance for NGS tumour profiling was observed across participating institutions, differences in the reporting of clinically relevant variants were observed, highlighting reporting as a gap where consensus on the part of Ontario laboratories is needed
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