Theory for planetary exospheres: III. Radiation pressure effect on the Circular Restricted Three Body Problem and its implication on planetary atmospheres

The planetary exospheres are poorly known in their outer parts, since the neutral densities are low compared with the instruments detection capabilities. The exospheric models are thus often the main source of information at such high altitudes. We present a new way to take into account analytically the additional effect of the stellar radiation pressure on planetary exospheres. In a series of papers, we present with an Hamiltonian approach the effect of the radiation pressure on dynamical trajectories, density profiles and escaping thermal flux. Our work is a generalization of the study by Bishop and Chamberlain (1989). In this third paper, we investigate the effect of the stellar radiation pressure on the Circular Restricted Three Body Problem (CR3BP), called also the photogravitational CR3BP, and its implication on the escape and the stability of planetary exospheres, especially for Hot Jupiters. In particular, we describe the transformation of the equipotentials and the location of the Lagrange points, and we provide a modified equation for the Hill sphere radius that includes the influence of the radiation pressure. Finally, an application to the hot Jupiter HD 209458b reveals the existence of a blow-off escape regime induced by the stellar radiation pressure

Theory for planetary exospheres: I. Radiation pressure effect on dynamical trajectories

The planetary exospheres are poorly known in their outer parts, since the neutral densities are low compared with the instruments detection capabilities. The exospheric models are thus often the main source of information at such high altitudes. We present a new way to take into account analytically the additional effect of the radiation pressure on planetary exospheres. In a series of papers, we present with an Hamiltonian approach the effect of the radiation pressure on dynamical trajectories, density profiles and escaping thermal flux. Our work is a generalization of the study by Bishop and Chamberlain (1989). In this first paper, we present the complete exact solutions of particles trajectories, which are not conics, under the influence of the solar radiation pressure. This problem was recently partly solved by Lantoine and Russell (2011) and completely by Biscani and Izzo (2014). We give here the full set of solutions, including solutions not previously derived, as well as simpler formulations for previously known cases and comparisons with recent works. The solutions given may also be applied to the classical Stark problem (Stark,1914): we thus provide here for the first time the complete set of solutions for this well-known effect in term of Jacobi elliptic functions

In the Name of Blue: Blue Joyce, Blue Gass, Blue Klein

This essay attempts to make color “run” in various ways, to make it run fast (color-fast) between ontological and logical categories. Three ways of becoming-blue, three steps into writing/painting via the color blue are traced: blue Joyce, blue Gass, blue Klein. Three “countries” of the blue, opening onto labile regimes of in-betweenness: between two roots of the verb “to be” (esse/*blû, both active in Joyce’s Ulysses), or between proper and common nouns (from William Gass to Klein’s gas or Joyce’s Gas from a Burner).Cet essai fait “couler” la couleur à partir de trois textes mettant variablement en défaut les catégories ontologiques et logiques. Trois devenirs-bleus, trois entrées en écriture/peinture via le “bleu” sont ici pris en filature : bleu Joyce ; bleu Gass ; bleu Klein. Trois “pays” du bleu où il s’agit de laisser entrer trois logiques labiles ou entre-deux : entre deux racines du verbe être (esse/*blû, à partir d’Ulysses de James Joyce), ou entre noms propres et noms de “choses” (de William Gass au gaz d’Yves Klein, ou au “gaz” de Gas from a Burner de James Joyce)

Prediciendo la descomponibilidad de la hojarasca: evaluación de caracteres funcionales de hoja, de broza y de propiedades espectrales de seis especies herbáceas del Mediterráneo

Algunos trabajos han explorado métodos fáciles y rápidos de evaluar la decomponibilidad de la broza de grandes conjuntos de especies. Aquí evaluamos tres de los más utilizados en seis especies mediterráneas herbáceas de diferentes familias y formas de vida: (1) 'caracteres de hojas verdes': caracteres de hojas vivas relacionadas a las estrategias de vida de las plantas; (2) 'caracteres de la broza': respiración de la broza durante incubaciones in vitro y propiedades iniciales de la broza; (3) 'propiedades espectrales de las hojas y de la broza': características espectrales (NIR) de las hojas verdes y de la broza. Analizamos las relaciones entre estos métodos y su consistencia para evaluar la tasa de descomposición de la broza en el campo. Las propiedades espectrales de hojas verdes fueron las más precisas para predecir la descomponibilidad a campo, seguidas por el contenido de materia seca de las hojas (LDMC) y el contenido inicial de compuestos no lábiles de la broza. La descomponibilidad in vitro se correlacionó marginalmente con la descomponibilidad a campo. La selección entre los predictores puede depender, entonces, de los instrumentos disponibles. LDMC es el método más económico y fácil de medir para grandes conjuntos de especies que, a su vez, fue constante dentro de las especies analizadas. Alternativamente, en el caso de tener el equipamiento y las calibraciones disponibles, los espectros NIR de las hojas verdes y de la broza inicial representan un método rápido para estimar la descomponibilidad y calidad de la broza al mismo tiempo. Nuestros resultados confirman evidencias previas que para las especies de sistemas semiáridos caracteres estructurales como LDMC y el contenido de compuestos no lábiles son propiedades importantes en el control de la descomponibilidad de la broza. La validez de nuestras conclusiones para un rango mayor de especies debería probarse en futuros estudios.Several studies attempted to find quick and easy methods to assess litter decomposability. We tested three frequently used methods on 6 Mediterranean herbaceous species from different plant families and life forms: (1) ‘green leaves traits’: traits of living leaves related to the strategies of living plants; (2) ‘litter traits’: litter respiration during in vitro incubation and initial litter properties; and (3) ‘leaf and litter spectral properties’: the spectral characteristics (NIR) of green leaves and litter. We analyzed the relationship between these methods and their consistency to assess litter decomposability in the field. Green leaves spectral properties were the most accurate to predict Several studies attempted to find quick and easy methods to assess litter decomposability. We tested three frequently used methods on 6 Mediterranean herbaceous species from different plant families and life forms: (1) ‘green leaves traits’: traits of living leaves related to the strategies of living plants; (2) ‘litter traits’: litter respiration during in vitro incubation and initial litter properties; and (3) ‘leaf and litter spectral properties’: the spectral characteristics (NIR) of green leaves and litter. We analyzed the relationship between these methods and their consistency to assess litter decomposability in the field. Green leaves spectral properties were the most accurate to predict field decomposability, followed by leaf dry matter content (LDMC) and initial content of non-labile compounds. In vitro decomposability marginally correlated with field decomposability. The selection among these predictors may then depend on the instruments available. LDMC is the easiest and least expensive, and is also a constant trait within species. Alternatively, if available, NIR spectra of green leaves and initial litter represent the quickest method for estimating decomposability and litter quality at the same time. Our findings confirm previous evidence that for species from semi-arid systems structural traits like LDMC and non-labile compounds content are important properties controlling species litter decomposability. The validity of our conclusions when a wider range of species is included remains to be tested. decomposability, followed by leaf dry matter content (LDMC) and initial content of non-labile compounds. In vitro decomposability marginally correlated with field decomposability. The selection among these predictors may then depend on the instruments available. LDMC is the easiest and least expensive, and is also a constant trait within species. Alternatively, if available, NIR spectra of green leaves and initial litter represent the quickest method for estimating decomposability and litter quality at the same time. Our findings confirm previous evidence that for species from semi-arid systems structural traits like LDMC and non-labile compounds content are important properties controlling species litter decomposability. The validity of our conclusions when a wider range of species is included remains to be tested.Fil: Perez Harguindeguy, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); ArgentinaFil: Cortez, Jacques. Centre d´Ecologie Fonctionnelle et Evolutive; FranciaFil: Garnier, Eric. Centre d´Ecologie Fonctionnelle et Evolutive; FranciaFil: Gillon, Dominique. Centre d´Ecologie Fonctionnelle et Evolutive; FranciaFil: Poca, María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentin

Diversity in Biorefinery : an interdisciplinary approachon Science, Business and "doubly green" Chemistry

International audienceThe word “biorefinery” was coined to describe an industrial process of cracking biomass resembling the industrial cracking of fossil carbon (Kamm and Kamm, 2005). But it can also be seen as an "Intermediary Object" (Vinck 2009) socially constructed by macroactors in European projects such as "Star-Colibri", with a view to developing a particular vision of the transition towards the use of renewable resources. Narrative approaches are mobilized by sociologists to describe the complexity of systemic change in a multilevel perspective (Grin, Rotmans and Schot, 2010). Narratives have also been used in Economics and Management of Technologies since the works of David (1985) to Dumez and Jeunemaitre (2005), to identify and describe various potential technological trajectories. We used a similar (analysis, cognitive process, method, procedure.) in the course of an interdisciplinary approach involving economists chemists and biochemists. Our "narrative approach" aims at highlighting the diversity of technological expectations. In the dominant vision of the biorefinery, large-scale units crack the biomass into a limited number (top 10 chemical intermediates) of standardized "small molecules", easily purified and introduced into the traditional petrochemical processes. Production of liquid fuels ("bio"-fuels) would enable economic operators to reach this large scale, while chemicals with high added value should ensure their economic balance (Bozell, Petersen 2010). However, other technical routes are worth considering: For example the intrinsic complexity and self-organization properties of biomass materials can be used as a way to introducing principles of green chemistry in processes operating more systematically on the macromolecular level ("one pot", whole plant, "reactive extrusion", modified starches, photochemistry and so on ..). They minimize fractionation steps and thus the use of energy or water. They can also entail smaller scale chemical units, which would not need to be stitched to the existing network of large-scale commodities production (of "bio"fuels,) and would be better rooted in local production areas. The discussion on the transition must therefore integrate the diversity of possible technical (ways) (routes) and examine how institutional policies support either of these solutions

L’étude interdisciplinaire des parfums anciens au prisme de l’archéologie, la chimie et la botanique : l’exemple de contenus de vases en verre sur noyau d'argile (Sardaigne, vie-ive siècle av. J.-C.)

Les analyses de contenus organiques ne sont pas encore systématiques, mais sont de plus en plus sollicitées dans le cadre de problématiques liées aux activités de production, de transformation de matières premières, aux méthodes et pratiques de stockage, de transport, de conservation, de consommation, et aux rituels d’offrandes faites aux divinités et aux défunts. Cependant, l’intérêt et la fiabilité des données issues de ces analyses chimiques dépendent de nombreux facteurs qui tiennent autant au choix, au nombre, à la conservation des objets et structures à échantillonner, qu’aux protocoles de prélèvements et d’analyses qui doivent être définis en fonction de la problématique proposée par les archéologues. Les données obtenues se présentent sous la forme de marqueurs chimiques partiellement conservés qui permettent de proposer des identifications plus ou moins précises de matières d’origine animale et végétale, posant souvent des problèmes d’interprétation et invitant à reconsidérer certaines des hypothèses issues d’autres sources. Cette problématique sera éclairée par un exemple portant sur le camphre et tiré du programme Perhamo (Produits et Résidus Huileux Antiques de la Méditerranée Occidentale), qui a permis d’analyser plus de 200 prélèvements de contenus de vases et de structures que l’on considérait comme liés à la production, au stockage et à l’utilisation d’huile et de parfums. Les contenus de sept vases en verre sur noyau d’argile ont fait l’objet d’analyses chimiques et d’interprétations botaniques.The analyses of organic contents are not yet systematic but are increasingly used in order to document the production, transformation, transportation, conservation and consumption, especially funerary offerings and rituals, practices of antique organic materials. However, the relevance and accuracy of the data obtained depends upon the choices and the representativeness of the materials samples, as much as upon the conservation conditions of the vessels and the methodologies selected, which need to be designed according to the set of questions formulated by archaeologists. The results obtained are degraded chemical markers allowing more or less trustworthy interpretations of the vegetal and/or animal organic components. The steps involved and the issues raised will be analysed through two examples taken form the Perhamo (Products and Oily Residues of the Western Mediterranean) program. This research program has allowed for the analysis of more than 200 samples of organic contents of vases and structures, considered linked to the production, stocking and utilisation of oil and perfume in the Mediterranean. The contents of seven glass vases were the object of chemical analyses and botanical interpretations

321. Deletion of Mutated GAA Repeats from the Intron 1 of the Frataxin Gene Using the CRISPR System Restores the Protein Expression in a Friedreich Ataxia Model

The CRISPR system is now widely used as a molecular tool to edit the genome. We used this technique in Friedreich Ataxia (FRDA), an inherited autosomal disease known to cause a decrease of the mitochondrial frataxin protein. Genetic analysis revealed a GAA repeat expansion within the intron 1 of the frataxin (FXN) gene. We used cells derived from the YG8sR mouse model where the mouse frataxin gene is knockout but contain a human FXN mutated transgene on one allele. We then deleted the GAA trinucleotide repeat using 2 specific guide RNAs (gRNAs) co-expressed with either S. pyogenes (Sp) or S. aureus (Sa) Cas9. We were able to monitored an increase up to 2-fold of frataxin mRNA and protein levels in clone cells. We also confirmed these results in vivo using DNA electroporation in the Tibialis anterior muscle of the YG8R mice. Ongoing in vivo investigation of a systemically injected AAV-DJ vector expressing the SaCas9 and 2 successful selected gRNAs in the mouse model YG8sR will hopefully provide more details answers on the efficacy of the approach and give us preliminary data to go forward for clinical trial. The deletion of the GAA repeats expansion then might be a highly valuable gene therapy approach for FRDA patients

Resveratrol Improves Survival, Hemodynamics and Energetics in a Rat Model of Hypertension Leading to Heart Failure

Heart failure (HF) is characterized by contractile dysfunction associated with altered energy metabolism. This study was aimed at determining whether resveratrol, a polyphenol known to activate energy metabolism, could be beneficial as a metabolic therapy of HF. Survival, ventricular and vascular function as well as cardiac and skeletal muscle energy metabolism were assessed in a hypertensive model of HF, the Dahl salt-sensitive rat fed with a high-salt diet (HS-NT). Resveratrol (18 mg/kg/day; HS-RSV) was given for 8 weeks after hypertension and cardiac hypertrophy were established (which occurred 3 weeks after salt addition). Resveratrol treatment improved survival (64% in HS-RSV versus 15% in HS-NT, p<0.001), and prevented the 25% reduction in body weight in HS-NT (P<0.001). Moreover, RSV counteracted the development of cardiac dysfunction (fractional shortening −34% in HS-NT) as evaluated by echocardiography, which occurred without regression of hypertension or hypertrophy. Moreover, aortic endothelial dysfunction present in HS-NT was prevented in resveratrol-treated rats. Resveratrol treatment tended to preserve mitochondrial mass and biogenesis and completely protected mitochondrial fatty acid oxidation and PPARα (peroxisome proliferator-activated receptor α) expression. We conclude that resveratrol treatment exerts beneficial protective effects on survival, endothelium–dependent smooth muscle relaxation and cardiac contractile and mitochondrial function, suggesting that resveratrol or metabolic activators could be a relevant therapy in hypertension-induced HF