The Raman non-coincidence effect of the 12C=O stretching mode of liquid acetone in chemical and in isotopic mixtures

Abstract The concentration dependences of the first moments of both the isotropic and anisotropic Raman bands of the C=O stretching mode (12C=O) of acetone in chemical mixtures of type [(CH3)2CO]x \u2013 [CCl4]1-x are compared with their dependences in isotopic mixtures of type [(CH3)212CO]x - [(CH3)213CO]1-x . The role of the intermolecular resonant vibrational coupling is discussed via the experimentally observable Raman non-coincidence effect, i.e. the difference in the frequency position between the anisotropic and isotropic first moments. The experimental results are in good agreement with (1) molecular dynamics simulations and Monte Carlo simulations and (2) analytical predictions within the framework of the mean-spherical approximation of the dipole-dipole interaction. With the help of [(CH3)213CO] occurring at natural abundance in the chemical mixture, and of [(CH3)213CO] at close to infinite dilution in the isotopic mixture, we are able to separate the environmentally induced frequency shifts from the measured anisotropic and isotropic first moments, thereby isolating the frequency shifts induced just by the intermolecular resonant vibrational coupling

The Effects of Coral Bleaching in The Northern Caribbean and Western Atlantic

The effects of bleaching and hurricanes on coral reefs in 2005 varied across the region and within countries. Some countries experienced intense widespread coral bleaching down to 35 m, while the effects of increased water temperatures were moderate to low in others. Coral mortality rates were low on average; most corals recovered quickly when water temperatures dropped. Greater human and financial resources are needed to monitor and effectively combat the effects of natural disasters. Regular monitoring and analysis of data are essential components of sound management strategies for sustainable environmental management and economic growth.https://scholar.dominican.edu/books/1107/thumbnail.jp

Quality of Life of Children with Congenital Heart Diseases: A Multicenter Controlled Cross-Sectional Study.

To assess the health-related quality of life (QoL) in children with congenital heart diseases (CHD) with a validated questionnaire in comparison with control children. We prospectively recruited 282 children with CHD aged from 8 to 18 years in two tertiary care centers (France and Belgium) and 180 same-age controls in randomly selected French schools. Children's QoL was self-reported with the KIDSCREEN-52 questionnaire and reported by parents with the KIDSCREEN-27. QoL scores of each dimension were compared between CHD and controls and between the classes of disease severity. Both centers were comparable for most demographic and clinical data. Age- and gender-adjusted self-reported QoL scores were lower in CHD children than in controls for physical well-being (mean ± SEM 45.97 ± 0.57 vs 50.16 ± 0.71, p < 0.0001), financial resources (45.72 ± 0.70 vs 48.85 ± 0.87, p = 0.01), peers/social support (48.01 ± 0.72 vs 51.02 ± 0.88, p = 0.01), and autonomy in the multivariate analysis (47.63 ± 0.69 vs 49.28 ± 0.85, p = 0.04). Parents-reported scores were lower in CHD children for physical (p < 0.0001), psychological well-being (p = 0.04), peers/social support (p < 0.0001), and school environment (p < 0.0001) dimensions. Similarly, the disease severity had an impact on physical well-being (p < 0.001), financial resources (p = 0.05), and peers/social support (p = 0.01) for self-reported dimensions, and on physical well-being (p < 0.001), psychological well-being (p < 0.01), peers/social support (p < 0.001), and school environment (p < 0.001) for parents-reported dimensions. However, in multivariate analysis on self-reported QoL, disease severity was significantly associated with the self-perception dimension only. Self-reported QoL of CHD children was similar to that of same-age healthy children in seven of 10 dimensions, but parents-reported QoL was impaired in four of five dimensions