323,124 research outputs found
L'influence de saint Augustin dans la littérature médiévale (communication S. Rayne)
No full textServane Rayne présentera une communication sur l'influence de saint Augustin dans la littérature médiévale le vendredi 18 mars 2016 dans le cadre du séminaire SCTAM de l'Université d'Angers. Renseignements pratiques: Séminaire de civilisation tardo-antique et médiévale Vendredi 18 mars 2016, 14h-17h Université d'Angers - Maison de la Recherche Germaine Tillon (Maison de la Recherch G. Tillion; Plan MSH) Organisatrice : Elisabeth Mathieu ([email protected]
CR "Source sur la littérature antique au XIVe s." (B. Dufal) - 5/03/13
No full textSont présents Elisa Brilli, Blaise Dufal, Edouard Garancher, Midoriko Kageyama, Paul-Joseph Michel, Marco Prost, Bernard et Micheline Rayne, Servane Rayne-Michel, David Reney. Servane Rayne-Michel introduit la séance en souhaitant la bienvenue aux nouveaux participants du séminaire et présente les travaux des dernières séances : les trois questions qui dirigent l'ensemble du cycle de cette année (1. l'opposition entre Cité de Dieu et cité du diable, mêlées, selon Augustin, dans le saeculum, ..
Sustainability and Environmental Chemistry in Semi-Arid/Arid Regions: A Unique Research Opportunity with Global Implications
No full textDr. Sierra Rayne will be speaking on the interplay of sustainability and environmental chemistry in semi-arid and arid regions worldwide. Drawing on his previous, current, and proposed research on organic and inorganic contaminants in aquatic systems, Dr. Rayne will illustrate the importance of multidisciplinary and interdisciplinary approaches towards tackling environmental problems. A key element of his work is looking at chemical dynamics in environmental matrices, and in particular, photochemically generated reactive intermediates and their impact on biological systems and net ecosystem functions. Semi-arid/arid regions also offer unique opportunities to focus on the role of photochemistry in the biogeochemical cycling of oxyanion-forming heavy metals such as arsenic, molybdenum, selenium, and uranium (among others). Given the importance of semi-arid/arid regions in hosting major mineral deposits, multidisciplinary environmental chemistry research can also help make contributions towards sustainability in the worldwide mining industry. These fields offer great opportunities for researchers and students interested in semi-arid/arid landscapes, and understanding the role and impact of these regions on global contaminant fluxes is at the core of Dr. Rayne’s program
Benchmarking the SPARC software program for estimating solubilities of naphthalene and anthracene in organic solvents
No full textThe SPARC software program was benchmarked for calculating the solubilities of two representative polyaromatic hydrocarbons (PAHs), naphthalene and anthracene, in a range of organic solvents at various temperatures. Although SPARC was able to reasonably approximate the solubilities of naphthalene in some organic solvents, gross errors were obtained for other solvents. For anthracene, poor prediction performance was observed in all solvents considered. Overall, the results suggest that SPARC is currently not suitable for accurately predicting the solubilities of representative PAHs relevant for the petroleum sector in various organic solvents
Correction: Turn-on fluorescent glucose transport bioprobe enables wash-free real-time monitoring of glucose uptake activity in live cells and small organisms
No full textCorrection for “Turn-on fluorescent glucose transport bioprobe enables wash-free real-time monitoring of glucose uptake activity in live cells and small organisms” by Monica S. Hensley et al., RSC Chem. Biol., 2025, 6, 987–995, https://doi.org/10.1039/D4CB00239C.
The authors regret that two contributors, Micaela Rayne Geborkoff and Professor Dr Thomas Werner, were inadvertently omitted from the original author list of this article. Both individuals made significant contributions to the research reported.
Micaela Rayne Geborkoff was involved in the design, planning, and execution of the Drosophila experiments, specifically in the growth and treatment of fruit fly larvae. Professor Dr Thomas Werner provided laboratory resources and supervision, and played a key role in the experimental design and execution of the in vivo work, particularly contributing to the results presented in Fig. 7
Structures, enthalpies of formation, and ionization energies for the parent and binary mixed carbon, silicon, nitrogen, and phosphorus cubane derivatives: A G4MP2 theoretical study
No full textGas phase standard state (298.15 K, 1 atm) structures, enthalpies of formation, and ionization energies (IEs) were calculated at the G4MP2 composite method level of theory for the parent and binary mixed carbon, silicon, nitrogen, and phosphorus cubane derivatives. Increasing nitrogen content increases the enthalpies of formation for the carbon-nitrogen, nitrogen-phosphorus, and silicon-nitrogen binary cubanes, with the opposite enthalpies of formation trend for increasing phosphorus content within the carbon-phosphorus, nitrogen-phosphorus, and silicon-phosphorus derivatives. Varying carbon/silicon content in the carbon-silicon cubanes results in no general trends for enthalpies of formation. Isomerization enthalpies within the homolog groups having more than one isomer vary widely with atomic composition and substitution patterns. Increasing nitrogen content of the carbon-nitrogen and nitrogen-phosphorus derivatives increases the IE, increasing silicon content in the carbon-silicon cubanes and phosphorus content of the carbon-phosphorus cubanes decreases the IE, while no IE clear trends are evident based on relative atomic content for the silicon-nitrogen and silicon-phosphorus compounds. The binary mixed carbon, silicon, nitrogen, and phosphorus cubane derivatives are predicted to display potentially tunable thermodynamic stability and redox behavior depending on the atom identities and relative positions
A G4MP2 theoretical study on the gas phase enthalpies of formation for various polycyclic aromatic hydrocarbons (PAHs) and other C~10~ through C~20~ unsaturated hydrocarbons
No full textGas phase enthalpies of formation at 298.15 and 1 atm (Δ~f~H~(g),298K~) were calculated using the atomization approach at the G4MP2 composite method level of theory for 86 polyaromatic hydrocarbons (PAHs) and other C~10~ through C~20~ unsaturated hydrocarbons. Where available, good agreement with prior experimental data and/or high level theoretical estimates was obtained. Linear regressions between semiempirical MNDO, MNDO-d, AM1, PM3, RM1, and PM6 estimated Δ~f~H~(g),298K~ and the corresponding G4MP2 values were employed to obtain G4MP2 corrected semiempirical Δ~f~H~(g),298K~ for a suite of 156 C~11~ through C~42~ unsaturated hydrocarbons and PAHs
Potential role of 2,2'-biphenylquinones in the carcinogenic/anti-cancer activity of dioxins
No full textModes of carcinogenicity for the well-known environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) have been investigated over the past several decades. However, the mechanisms underlying TCDD carcinogenicity are still unclear. Recent work also suggests TCDD may have anti-cancer activity. Based on established photochemical generation of reactive 2,2'-biphenylquinone intermediates from dioxins, a novel toxicological mechanism for TCDD that may be operative is proposed. 2,2'-Biphenylquinones may be obtained via biochemical activation of dioxins such as TCDD, and these intermediates may play a role in expressing both the carcinogenic and anti-cancer activities of this important contaminant class. The broader research community is encouraged to consider this potential new mechanism for dioxin toxicology in the design of future studies, the positive or negative findings from which will supplement the datasets developed by previous and current research groups
Re-evaluating the list of high-production chemicals predicted to become Arctic contaminants
No full textThe large number of historical and current organic chemicals in commerce, and the ability of these compounds to make their way from industrial to remote regions, has resulted in concerted efforts to predict which chemicals have the capacity to migrate from where they are used/disposed to areas such as the Arctic. A suite of 120 high production volume chemicals has been recently screened from an initial dataset of >100,000 compounds and listed as potential Arctic contaminants. In the current work, we critically assess members of this proposed list for their possible rapid reactivity in environmental systems that would prevent substantial accumulation or transport in the environment and accumulation in vivo, as well as whether the investigated physicochemical properties are adequate for the intended environmental screening purposes
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