179 research outputs found
Using media to improve the informed consent process for youth undergoing pediatric endoscopy and their parents.
Background and study aims Youth undergoing pediatric endoscopic procedures and their parents demonstrate suboptimal comprehension of the informed consent (IC) process. We developed informational videos discussing key IC elements for pediatric endoscopy and evaluated their effects on youth and parental comprehension of the IC process. Patients and methods A randomized controlled trial of the video intervention was performed among youth undergoing endoscopy and their parents at an academic children's hospital. Randomization occurred at the time of enrollment using permutated blocks. Following the IC process with the proceduralist, subjects underwent structured interviews to assess IC comprehension. An Informed Consent Overall Score (ICOS: range 0 - 4) for comprehension was calculated. Results Seventy-seven pairs of children and their parents participated. Intervention recipients (N = 37 pairs) demonstrated higher ICOS scores as compared to control counterparts (mean (standard deviation): 3.6 (0.7) v. 2.9 (0.9), intervention v. control parents, P < 0.0001 and 2.7 (1.1) v. 1.7 (1.1), intervention v. control youth, P < 0.0001). Conclusions A media intervention addressing key elements of the IC process for pediatric endoscopy was effective in improving comprehension of IC for youth undergoing endoscopic procedures and their parents
A Sr-Rich Star on the Main Sequence of Omega Centauri
Abundance ratios relative to iron for carbon, nitrogen, strontium and barium
are presented for a metal-rich main sequence star ([Fe/H]=--0.74) in the
globular cluster omega Centauri. This star, designated 2015448, shows depleted
carbon and solar nitrogen, but more interestingly, shows an enhanced abundance
ratio of strontium [Sr/Fe] ~ 1.6 dex, while the barium abundance ratio is
[Ba/Fe]<0.6 dex. At this metallicity one usually sees strontium and barium
abundance ratios that are roughly equal. Possible formation scenarios of this
peculiar object are considered.Comment: 13 pages, 3 figures. Accepted to ApJ
A chemical signature from fast-rotating low-metallicity massive stars: ROA 276 in ω Centauri
© 2017. The American Astronomical Society. All rights reserved. We present a chemical abundance analysis of a metal-poor star, ROA 276, in the stellar system ω Centauri. We confirm that this star has an unusually high [Sr/Ba] abundance ratio. Additionally, ROA 276 exhibits remarkably high abundance ratios, [X/Fe] , for all elements from Cu to Mo along with normal abundance ratios for the elements from Ba to Pb. The chemical abundance pattern of ROA 276, relative to a primordial ω Cen star ROA 46, is best fit by a fast-rotating low-metallicity massive stellar model of 20 , [Fe/H] = -1.8, and an initial rotation 0.4 times the critical value; no other nucleosynthetic source can match the neutron-capture element distribution. ROA 276 arguably offers the most definitive proof to date that fast-rotating massive stars contributed to the production of heavy elements in the early universe
Early-life DNA methylation profiles are indicative of age-related transcriptome changes.
BACKGROUND: Alterations to cellular and molecular programs with brain aging result in cognitive impairment and susceptibility to neurodegenerative disease. Changes in DNA methylation patterns, an epigenetic modification required for various CNS functions are observed with brain aging and can be prevented by anti-aging interventions, but the relationship of altered methylation to gene expression is poorly understood.
RESULTS: Paired analysis of the hippocampal methylome and transcriptome with aging of male and female mice demonstrates that age-related differences in methylation and gene expression are anti-correlated within gene bodies and enhancers. Altered promoter methylation with aging was found to be generally un-related to altered gene expression. A more striking relationship was found between methylation levels at young age and differential gene expression with aging. Highly methylated gene bodies and promoters in early life were associated with age-related increases in gene expression even in the absence of significant methylation changes with aging. As well, low levels of methylation in early life were correlated to decreased expression with aging. This relationship was also observed in genes altered in two mouse Alzheimer\u27s models.
CONCLUSION: DNA methylation patterns established in youth, in combination with other epigenetic marks, were able to accurately predict changes in transcript trajectories with aging. These findings are consistent with the developmental origins of disease hypothesis and indicate that epigenetic variability in early life may explain differences in aging trajectories and age-related disease
Abundances on the Main Sequence of Omega Centauri
Abundance ratios of carbon, nitrogen and strontium relative to iron,
calculated using spectrum synthesis techniques, are given for a sample of main
sequence and turnoff stars that belong to the globular cluster omega Centauri.
The variations of carbon, nitrogen and/or strontium show several different
abundance patterns as a function of [Fe/H]. The source of the
enhancements/depletions in carbon, nitrogen and/or strontium may be enrichment
from asymptotic giant branch stars of low (1--3 solar masses) and intermediate
(3--8 solar masses) mass. Massive rotating stars which produce excess nitrogen
without carbon and oxygen overabundances may also play a role. These abundances
enable different contributors to be considered and incorporated into the
evolutionary picture of omega Cen.Comment: 43 Pages, 13 Figures. Accepted for publication in Ap
A Chemical Signature from Fast-rotating Low-metallicity Massive Stars: ROA 276 in omega Centauri
New biomaterials from renewable resources – amphiphilic block copolymers from δ-decalactone
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