Natural rubber based films integrating Zosteric acid analogues as bioactive monomers

International audienc

Adherent and Invasive Escherichia coli Is Associated with Granulomatous Colitis in Boxer Dogs

The mucosa-associated microflora is increasingly considered to play a pivotal role in the pathogenesis of inflammatory bowel disease. This study explored the possibility that an abnormal mucosal flora is involved in the etiopathogenesis of granulomatous colitis of Boxer dogs (GCB). Colonic biopsy samples from affected dogs (n = 13) and controls (n = 38) were examined by fluorescent in situ hybridization (FISH) with a eubacterial 16S rRNA probe. Culture, 16S ribosomal DNA sequencing, and histochemistry were used to guide subsequent FISH. GCB-associated Escherichia coli isolates were evaluated for their ability to invade and persist in cultured epithelial cells and macrophages as well as for serotype, phylogenetic group, genome size, overall genotype, and presence of virulence genes. Intramucosal gram-negative coccobacilli were present in 100% of GCB samples but not controls. Invasive bacteria hybridized with FISH probes to E. coli. Three of four GCB-associated E. coli isolates adhered to, invaded, and replicated within cultured epithelial cells. Invasion triggered a “splash”-type response, was decreased by cytochalasin D, genistein, colchicine, and wortmannin, and paralleled the behavior of the Crohn's disease-associated strain E. coli LF 82. GCB E. coli and LF 82 were diverse in serotype and overall genotype but similar in phylogeny (B2 and D), in virulence gene profiles (fyuA, irp1, irp2, chuA, fepC, ibeA, kpsMII, iss), in having a larger genome size than commensal E. coli, and in the presence of novel multilocus sequence types. We conclude that GCB is associated with selective intramucosal colonization by E. coli. E. coli strains associated with GCB and Crohn's disease have an adherent and invasive phenotype and novel multilocus sequence types and resemble E. coli associated with extraintestinal disease in phylogeny and virulence gene profile

Influence of Small Scale Heterogeneity on CO2 Trapping Processes in Deep Saline Aquifers

The physical mechanism of CO2 trapping in porous media by capillary trapping (pore scale) incorporates a number of related processes, i.e. residual trapping, trapping due to hysteresis of the relative permeability, and trapping due to hysteresis of the capillary pressure. Additionally CO2 may be trapped in heterogeneous media due to difference in capillary pressure entry points for different materials (facies scale). The amount of CO2 trapped by these processes depends upon a complex system of non-linear and hysteretic relationships including how relative permeability and capillary pressure vary with brine and CO2 saturation, and upon the spatial variation in these relationships as caused by geologic heterogeneity. Geological heterogeneities affect the dynamics of CO2 plumes in subsurface environments. Recent studies have led to new conceptual and quantitative models for sedimentary architecture in fluvial deposits over a range of scales that are relevant to the performance of some deep saline reservoirs. We investigated how the dynamics of a CO2 plume, during and after injection, is influenced by the hierarchical and multi-scale stratal architecture in such reservoirs. The results strongly suggest that representing small scales features (decimeter to meter), including their organization within a hierarchy of larger-scale features, is critical to understanding trapping processes

Croisées des chemins

Les croisements de rues comme de routes sont des lieux qui fixent certains types d’activités en lien avec le voyage, avec le déplacement sur des distances courtes ou longues, connues ou inconnues : s’arrêter, choisir une direction, se préparer à partir… Ils sont aussi le lieu de rencontres, de relais, d’échanges de marchandise, d’offres de service… Autant d’activités (boutique, entrepôt, atelier, hôtellerie...) qui laissent également des traces. Et au-delà de ces aspects concrets, ou en lien avec eux, les croisements sont liés à des croyances et des pratiques religieuses (autels, temples…) et/ou funéraires (tombe, cénotaphe, nécropole). Sur quels éléments se baser, en archéologie, pour identifier ces carrefours (topographie, bornes, raccords de voiries, types de trottoirs ou de bordures, signalisation…) ? Peut-on distinguer, par exemple, ceux qui marquent des limites sociales ou politiques, entre peuples, entre agglomérations, entre quartiers… ? The crossroads of streets and roads are where certain types of activities related to travel take place, moving over short or long distances, known or unknown: stopping, choosing a direction, preparing to leave, etc. Crossroads also act as places to meet, effect handovers, exchange goods and offer services, and all of these activities leave their mark (e.g. shops, warehouses, workshops, hotels...). Beyond these concrete aspects, there are countless cases where crossroads are linked to religious beliefs and practices (e.g. altars, temples) and/or funerary practices (burial, cenotaph, necropolis). But what elements should archaeology use in order to identify these crossroads (e.g. topography, landmarks, road connections, types of pavements or kerbs, signs)? And can we distinguish, for example, those that mark social or political limits, between people, between settlements, between neighbourhoods, etc? Las encrucijadas de calles y caminos son lugares que fijan cierto tipo de actividades relacionadas con el viaje, el desplazamiento sobre distancias largas o cortas, conocidas o desconocidas: detenerse, elegir una dirección, prepararse a partir… Las encrucijadas son también lugares de encuentro, de relevo, de intercambios de mercancías, de ofertas de servicio… un sinnúmero de actividades -tales como tiendas, almacenes, talleres, hostelería- que dejan igualmente huellas. Más allá de estos aspectos concretos, son innumerables los casos donde las encrucijadas están relacionadas con creencias y prácticas religiosas (altares, templos…) y/o funerarias (tumbas, cenotafios, necrópolis). ¿Sobre qué elementos debe basarse la arqueología para identificar dichos cruces (topografía, hitos, empalmes de redes viales, tipos de aceras o de bordes, señalización y demás)? ¿Es posible distinguir, por ejemplo, aquellos que marcan límites sociales o políticos entre pueblos, entre aglomeraciones, entre barrios, etcétera