Engineering framework for Safran interlocked ceramics components

CMC technologies, emerging for civil aircraft engines, require to adapt designers and manufacturers rules, which mainly come from metal experience. Many aspects should be rethought: strain criteria are low compared to metal, dimensions are small compare to PMC, and geometrical requirements for aerodynamic performance are very challenging compare to spatial and brakes applications. To cope with these engineering stakes, it’s priceless to integrate the sound knowledge of CMC’s specific relationships across scales and disciplines built by the scientific community. Please click Additional Files below to see the full abstract

SiC-based ceramic matrix composite behavior enhancement for gas turbines hot sections

Silicon carbide fibers reinforced silicon carbide based-matrix composites (SiC/SiC CMC’s), are probably becoming a major leading alternative for the design and manufacturing of the next gaz turbine engines hot parts as airfoils, shroud, combustion chambers. These materials offer higher temperature capability than the current state-of-the-art metallic superalloys and tougher than the monolithic ceramic. The growing interest in CMC technologies development is directly linked to the new short-term engine design constraints in the context of air travel booming, namely : a drastic decreasing of community noise and air polluting emissions and a specific fuel consumption decrease. During the last fifteen years, substantial research efforts have been devoted towards evaluating for a wide range of CMCs, as oxide and carbide and manufaturing routes, as CVI, MI, powder impregnation, PIP. Building on past materials efforts in the field of both space launchers and military engines aircraft, Safran continued to enhance CMC technologies for commercial aircraft engines. Considering this new target, one of the key issues related to this emerging technology is to develop and industrialize materials offering high thermomechanical design allowables and stable lifetime properties, in representative environment. To reach these goals, an important work has been done, in the implementation of Melt –Infiltrated SiC/SiC CMC and T/EBC top-coat. Please click Additional Files below to see the full abstract

Faecal Escherichia coli as biological indicator of spatial interaction between domestic pigs and wild boar (Sus scrofa) in Corsica

On the Mediterranean island of Corsica, cohabitation between sympatric domestic pigs and Eurasian wild boar (Sus scrofa) is common and widespread and can facilitate the maintenance and dissemination of several pathogens detrimental for the pig industry or human health. In this study, we monitored a population of free-ranging domestic pigs reared in extensive conditions within a 800-ha property located in Central Corsica which was frequently visited by a sympatric population of wild boar between 2013 and 2015. We used GPS collars to assess evidence of a spatially shared environment. Subsequently, we analysed by PFGE of XbaI-restricted DNA if those populations shared faecal Escherichia coli clones that would indicate contact and compared these results with those collected in a distant (separated by at least 50 km) population of wild boar used as control. Results showed that one of eight wild boars sampled in the study area shed E. coli XbaI clones identical to clones isolated from domestic pig sounders from the farm, while wild boar populations sampled in distant parts of the study area shared no identical clone with the domestic pigs monitored. Interestingly, within the sampled pigs, two identical clones were found in 2013 and in 2015, indicating a long-time persisting colonization type. Although the method of isolation of E. coli and PFGE typing of the isolates requires intensive laboratory work, it is applicable under field conditions to monitor potential infectious contacts. It also provides evidence of exchange of microorganisms between sympatric domestic pigs and wild boar populations. (Résumé d'auteur

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Protection from ultraviolet damage and photocarcinogenesis by vitamin d compounds

© Springer Nature Switzerland AG 2020. Exposure of skin cells to UV radiation results in DNA damage, which if inadequately repaired, may cause mutations. UV-induced DNA damage and reactive oxygen and nitrogen species also cause local and systemic suppression of the adaptive immune system. Together, these changes underpin the development of skin tumours. The hormone derived from vitamin D, calcitriol (1,25-dihydroxyvitamin D3) and other related compounds, working via the vitamin D receptor and at least in part through endoplasmic reticulum protein 57 (ERp57), reduce cyclobutane pyrimidine dimers and oxidative DNA damage in keratinocytes and other skin cell types after UV. Calcitriol and related compounds enhance DNA repair in keratinocytes, in part through decreased reactive oxygen species, increased p53 expression and/or activation, increased repair proteins and increased energy availability in the cell when calcitriol is present after UV exposure. There is mitochondrial damage in keratinocytes after UV. In the presence of calcitriol, but not vehicle, glycolysis is increased after UV, along with increased energy-conserving autophagy and changes consistent with enhanced mitophagy. Reduced DNA damage and reduced ROS/RNS should help reduce UV-induced immune suppression. Reduced UV immune suppression is observed after topical treatment with calcitriol and related compounds in hairless mice. These protective effects of calcitriol and related compounds presumably contribute to the observed reduction in skin tumour formation in mice after chronic exposure to UV followed by topical post-irradiation treatment with calcitriol and some, though not all, related compounds

Averting biodiversity collapse in tropical forest protected areas

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon¹⁻³. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses⁴⁻⁹. As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world’s major tropical regions. Our analysis reveals great variation in reserve ‘health’: about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.Keywords: Ecology, Environmental scienc

La grotte ornée Mayenne-Sciences (Thorigné-en-Charnie, Mayenne) : un exemple d'art pariétal d'époque gravettienne en France septentrionale

The decorated cave of Mayenne-Sciences (Thorigné-en-Charnie, Mayenne) is characterized by four main features. It is geographically isolated, far away from the main regions such as Aquitany and Lot. It is culturally isolated since it belongs to the series of nine caves or shelters attributed to the Upper Palaeolithic in Northen France, like the caves of Gouy and Orival in Normandy, Boutigny, Le Croc-Martin and Les Trois Pignons in the département of Essonne, the Grotte du Cheval and the Grande Grotte of Arcy-sur-Cure in Burgundy, and Church Hole in England. Now, apart from the caves of the Cure valley, the other series of artistic documents can all be attributed to the Magdalenian, while the radiocarbon datation of pigments obtained from a horse of Mayenne-Sciences goes up to about 25 000 years, that is to the Gravettian. It is archaeologically isolated, the sites were excavated a long time ago, so it is impossible to link the stratigraphic levels to those of the main sites of reference in Périgord or Poitou-Charentes. It is "aberrant" from the stylistic point of view as well as for the symbolic designs. After a thoroughly analysis and definition of the geological, archaeological and artistic contexts of the cave, each representation is precisely described. A survey of the sites where parietal art and mobiliary art were found in the close vicinity of Mayenne-Sciences, is following ; then a deepen analysis enables us to set Mayenne-Sciences within a figurative bias mainly flourishing in Europe during the pre-Magdalenian which we propose to call "art de la silhouette ". It is demonstrated at the end that the "aberrant" feature of the decoration of Mayenne-Sciences is part of its isolation at the border of the main Prehistoric cultural currents (schemes ?) as it is for other examples of decorated caves. These caves can be put together under the concept of "grotte limite ", that is caves situated on the boundary of the influence of a special area which might be in the case of Mayenne-Sciences the Quercy.La grotte ornée Mayenne-Sciences (Thorigné-en-Charnie, Mayenne) possède quatre caractéristiques principales : 1) elle est isolée géographiquement, complètement reléguée à l'écart des grandes « provinces » comme l'Aquitaine et le Lot ; 2) elle est isolée culturellement : elle fait en effet partie du groupe des neuf cavités ou abris attribués au Paléolithique supérieur du nord de la France, avec les grottes de Gouy et d'Orival en Normandie, Boutigny, Le Croc-Marin et Les Trois Pignons en Essonne, la grotte du Cheval et la Grande Grotte d'Arcy-sur-Cure en Bourgogne, et Church Hole en Angleterre ; or, les grottes de la vallée de la Cure mises à part, toutes les autres manifestations artistiques peuvent être attribuées au Magdalénien, tandis que deux datations radiocarbones sur un cheval de Mayenne-Sciences ont fourni une datation d'époque gravettienne d'environ 25 000 ans ; 3) elle est isolée archéologiquement : l'ancienneté des fouilles ne permet pas de raccorder entre elles les séquences du Paléolithique supérieur retrouvées à proximité de celles des grands sites de référence du Périgord et du Poitou-Charentes ; 4) elle est « aberrante » du double point de vue du style et des constructions symboliques. Après une étude exhaustive, qui nous verra analyser et préciser les contextes géologique, archéologique et artistique de la grotte, nous décrirons précisément chacune de ses représentations. Nous tenterons ensuite d'établir une synthèse des sites d'art pariétal et mobilier dans le voisinage « immédiat » de Mayenne-Sciences puis, poussant plus loin notre analyse, de la replacer au sein d'une tendance figurative que nous proposons d'appeler « art de la silhouette », tendance qui fut majoritaire dans l'Europe anté-magdalénienne. Nous montrerons finalement que le caractère « aberrant » du décor de Mayenne-Sciences participe de son isolement aux marges des grands courants culturels préhistoriques, comme pour d'autres exemples de grottes ornées. Celles-ci seront regroupées sous le terme de « grottes-limites », grottes situées à l'extrémité de la zone d'influence d'une « province » particulière qui, dans le cas de Mayenne-Sciences, se situerait probablement dans la région du Quercy.La cueva ornada de Mayenne-Sciences (Thorigné-en-Charnie, Mayenne) posee cuatro caracteristicas principales : 1) está aislada geográficamente, siendo apartada de las grandes "provincias" como son Aquitania o el Lot ; 2) está aislada culturalmente : en efecto, forma parte del grupo de nueve cavidades o abrigos atribuidos al Paleolitico superior del Norte de Francia (con las cuevas de Gouy y Orival en Normandia, Boutigny, Le Croc-Marin y Les Trois Pignons en Essone, la grotte du Cheval y la Grande Grotte de Arcy-sur-Cure en Borgona, y Church Hole en Inglaterra) ; sin embargo, si se exceptúa las cuevas del valle de la Cure, todas las otras manifestaciones artisticas pueden atribuirse al Magdaleniense, mientras que dos dataciones 14C efectuadas en un caballo de Mayenne-Sciences remiten a una época gravetiense de 25 000 anos más o menos ; 3) esta aislada arqueológicamente, pues el carácter antiguo de las excavaciones no permite juntar las secuencias del Paleolitico superior encontradas a proximidad con las de otros grandes sitios de referencia del Périgord o de Poitou-Charentes ; 4) es "aberrante" desde el punto de vista del estilo y de las construcciones simbolicas. Tras un estudio exhaustive, en el que analizaremos y estableceremos con precision el contexto geologico, arqueológico y artistico de la cueva, describiremos detenidamente cada unas de sus representaciones. Intentaremos luego establecer una sintesis de los sitios de arte parietal y mobiliario en las inmediaciones de Mayenne-Sciences. Conduciendo mas alla nuestro analisis, trataremos de situarla en el contexto de una tendencia figurativa que proponemos nombrar "art de la silhouette ". Dicha tendencia fue mayoritaria en la Europa ante-magdaleniense. Mostraremos, por fin, que el caracter "aberrante" del decorado de Mayenne-Sciences contribuye a aislarla al margen de las grandes corrientes culturales prehistoricas, al igual que ocurre con otros ejemplos de cuevas ornadas. Estas cuevas se reunen bajo el término de "grotte-limite ", siendo situadas al extremo de la zona de influencia de una "provincia" particular, que en el caso de Mayenne-Sciences se situaria probablemente en la región de Quercy.Pigeaud Romain, Bouchard Michel, Laval Eric. La grotte ornée Mayenne-Sciences (Thorigné-en-Charnie, Mayenne) : un exemple d'art pariétal d'époque gravettienne en France septentrionale. In: Gallia préhistoire, tome 46, 2004. pp. 1-154

OPILAND : identification de la perception des territoires par la fouille de texte

National audienceDe nombreux travaux ont été réalisés en extraction d'informations et plus particulièrement en fouille de données d'opinions dans des contextes spécifiques tels que les critiques de films, les évaluations de produits commerciaux, les discours électoraux... Dans le cadre du projet SENTERRITOIRE, nous nous posons la question de l'adéquation de ces méthodes pour des documents associés à l'aménagement des territoires. Ces documents renferment différents types d'informations se rapportant à des acteurs, des opinions, des informations géographiques, et tout autre aspect lié plus généralement à la notion de territoire. Cependant, il est extrêmement difficile d'identifier puis de lier les opinions à ces informations. Après avoir souligné les limites des propositions actuelles et les verrous soulevés par les données textuelles associées, nous proposons la mé- thode semi-automatique nommée OPILAND (OPinion mIning from LAND-use planning documents) combinant une chaîne de Traitement Automatique du Lan- gage Naturel et des techniques de Fouilles de Textes pour (1) détecter les entités nommées de type lieu et organisation, (2) construire un vocabulaire d'opinions relatif au domaine d'application, et (3) identifier les opinions relatives aux entités nommées traitées. Les expérimentations sont menées sur des données du bassin de Thau (France), puis appliquées sur trois corpus relatifs à d'autres domaines afin de mettre en avant la généricité de notre approche

Are opinions expressed in land-use planning documents?

International audienceA great deal of research on information extraction from textual datasets has been performed in specific data contexts, such as movie reviews, commercial product evaluations, campaign speeches, etc. In this paper, we raise the question on how appropriate these methods are for documents related to land-use planning. The kind of information sought concerns the stakeholders, sentiments, geographic information, and everything else related to the territory. However, it is extremely challenging to link sentiments to the three dimensions that constitute geographic information (location, time, and theme). After highlighting the limitations of existing proposals and discussing issues related to textual data, we present a method called OPILAND (OPinion mIning from LAND-use planning documents) designed to semi-automatically mine opinions related to named-entities in specialized contexts. Experiments are conducted on a Thau lagoon dataset (France), and then applied on three datasets that are related to different areas in order to highlight the relevance and the broader applications of our proposal