Extensive High-Accuracy Thermochemistry and Group Additivity Values for Halocarbon Combustion Modeling

Standard enthalpies, entropies, and heat capacities are calculated for 16,813 halocarbons using an automated high-fidelity thermochemistry workflow. This workflow generates conformers at density functional tight binding (DFTB) level, optimizes geometries, calculates harmonic frequencies, and performs 1D hindered rotor scans at DFT level, and computes electronic energies at G4 level. The computed enthalpies of formation for 400 molecules show good agreement with literature references, but the majority of the calculated species have no reference in the literature. Thus, this work presents the most accurate thermochemistry for many halocarbons to date. This new data set is used to train an extensive ensemble of group additivity values and hydrogen bond increment groups within the Reaction Mechanism Generator (RMG) framework. On average, the new group values estimate standard enthalpies for halogenated hydrocarbons within 3 kcal/mol of their G4 values. A significant contribution towards automated mechanism generation of halocarbon combustion, this research provides thermochemical data for thousands of novel halogenated species and presents a self-consistent set of halogen group additivity values

Midiendo una metrópoli: metodología y asentamiento en Chunchucmil, Yucatán

Chunchucmil, centro urbano del noroeste de Yucatán, fue uno de los sitios mayas más extensos y densamente poblados del Clásico Temprano, aunque no tiene textos glíficos ni pirámides enormes. Diez temporadas de mapeo han revelado que el sitio tuvo un patrón de asentamiento complejo que se puede dividir en varias zonas, basándose en datos tales como: la presencia de conjuntos arquitectónicos ceremoniales, la densidad de residencias y el nivel de participación en la economía urbana. Esta investigación se enfoca en el difícil trabajo de definir los límites de la ciudad y presentar estimaciones sobre el tamaño de su población.<br>Chunchucmil (northwest Yucatan, Mexico) and other large Maya sites from the Classic period often do not exhibit clear edges. Though clusters of massive architecture define the center of these sites, delimiting the extent of settlement sometimes requires arbitrary judgments. Yet many issues depend upon where those edges are and what they are like. For example, identities that may be shared, contested, and imagined in the social and physical construction of boundaries within and around sites. Research at Chunchucmil furnishes a number of lines of evidence for delimiting the edges of this city and the ways in which households beyond the edge affiliated themselves with the site. In other words, spatial concepts such as site and city are not necessarily isomorphic with relational concepts such as community. This paper presents the results of our fieldwork at the edges of Chunchucmil and discusses the kinds of difference that constitute community identity

Médecine éco-responsable, mirée à l’aune de la santé individuelle ou du bien-être collectif ?

International audienceThe progress of medicine and its technical complexity require an ever-increasing amount of more and more varied resources. Similarly, human activities and care activities are responsible for a large number of toxic discharges (Hancock et al., 2001) whose consequences on environmental degradation (environmental diseases, extreme weather events) and human health (increase in emerging and re-emerging infectious diseases, famine, war) are already perceptible (Haines & Ebi, 2019). The right to health for each individual and the caregiver's duty to do everything possible to optimize the care of his (or her) patient therefore come up against the moral principle of responsibility for the ecosystem preservation and the health of future generations. Because a medical doctor must ensure that he does not treat his patients by making others sick, an ethical reflection has been conducted on the possibilities for a more efficient medicine at a collective level, while reconciling the benefits of individual medicine.Médecine éco-responsable, mirée à l'aune de la santé individuelle ou du bien-être collectif ? Les progrès de la médecine et sa technicité croissante nécessitent une quantité grandissante de ressources toujours plus variées. De la même façon, les activités humaines et les activités de soins sont pourvoyeuses d'un grand nombre de rejets toxiques (Hancock et al., 2001) dont les conséquences sur la dégradation environnementale (maladies environnementales, phénomènes météorologiques extrêmes) et la santé humaine (augmentation de maladies infectieuses émergentes et ré-émergentes, famines, guerres) sont déjà observables (Haines & Ebi, 2019). Le droit à la santé de chaque individu ainsi que le devoir du soignant de tout mettre en oeuvre pour optimiser la prise en charge de son malade se heurtent donc au principe moral de responsabilité pour la préservation de l'écosystème et de la santé des générations futures. Parce qu'un médecin doit s'assurer de ne pas soigner ses patients en rendant d'autres personnes malades, une reflexion éthique a été menée sur les possibles pour une médecine plus performante au plan collectif, tout en conciliant les bénéfices de la médecine individuelle

Accumulation of hydroxyproline rich glycoprotein m RNAs in infected or ethylene treated melon plants

National audienc

Linear correlation between specific surface and grafting density of tunable aerogels of microfibrillated cellulose from different origins

International audienc

Machine learning analysis of pregnancy data enables early identification of a subpopulation of newborns with ASD

International audienceTo identify newborns at risk of developing ASD and to detect ASD biomarkers early after birth, we compared retrospectively ultrasound and biological measurements of babies diagnosed later with ASD or neurotypical (NT) that are collected routinely during pregnancy and birth. We used a supervised machine learning algorithm with a cross-validation technique to classify NT and ASD babies and performed various statistical tests. With a minimization of the false positive rate, 96% of NT and 41% of ASD babies were identified with a positive predictive value of 77%. We identified the following biomarkers related to ASD: sex, maternal familial history of auto-immune diseases, maternal immunization to CMV, IgG CMV level, timing of fetal rotation on head, femur length in the 3rd trimester, white blood cell count in the 3rd trimester, fetal heart rate during labor, newborn feeding and temperature difference between birth and one day after. Furthermore, statistical models revealed that a subpopulation of 38% of babies at risk of ASD had significantly larger fetal head circumference than age-matched NT ones, suggesting an in utero origin of the reported bigger brains of toddlers with ASD. Our results suggest that pregnancy follow-up measurements might provide an early prognosis of ASD enabling pre-symptomatic behavioral interventions to attenuate efficiently ASD developmental sequels