Les otolithes de Téléostéens des faluns Sallomaciens d'Orthez et de Sallespisse (Miocène moyen d'Aquitane méridionale, France)

The study of the otoliths from the Sallomacian coquinas of Orthez and Sallespisse yielded 40 teleostean fish species of which two are new to science: Ilisha nijsseni and Diplodus kaerrerae. Among these, at least 8 are still living or very near to extant species.The association is dominated by a neritic shallow water fauna, much comparable to the extant fauna of the west-african coast between the Canary Islands and Senegal. The fossil species Brachydeuterus latior, Dentex (Polysteganus) aff. gregarius and Umbrina pyrenaica of the Sallomacian of Aquitaine are considered vicariants of the extant west-african species Brachydeuterus auritus, Dentex (Polysteganus) maroccanus and Umbrina cirrhosa.No attempt was made to interpret the fauna biostratigraphically, because the faunas of the underlying and overlying strata are still unknown

Progrès récents dans la connaissance des gisements cénozoïques en Aquitaine méridionale (Challose, Béarn et Bas-Adour; SW France)

The present paper presents the guide book of the excursion of the « Groupe d'Etude du Paleogene» in southern Aquitaine (4-6 september 2000), organized by the authors. Numerous Paleogene sections are discussed. Several of them were never described in detail previously: various sections on the Lespontes river at Saint-Lon-Ies-Mines (Middle and Upper Eocene), others on the road from Gan to Rebenacq (Paleocene-Ypresian), in the Gan area (Ypresian) and at Lahosse (Rupelian). Several classic sites are also presented and updated. Special attention has been given to the fIlling of the Saubrigues paleocanyon, with deposits ranging from Chattian to Langhian age. The stratigraphy of all studied levels is detailed with calcareous nannoplankton analyses, and for several sections, paleoecological data based on the analysis of fish otoliths and microbenthos (foraminifers, ostracods) are presented. This provides a series of southern Aquitaine reference localities for any complementary study. Moreover, these localities are well calibrated in time and exemplify the wide variety of facies that can be observed in the marine sedimentation realm of this region

Stratigraphie, nannofossiles calcaires et foraminifères de la coupe du Ruisseau de Lespontes à Saint-Lon-Les-Mines (Eocène moyen et supérieur d'Aquitaine, France)

Detailed analysis of a series of outcrop sections along the Lespontes River and its tributaries at Saint-Lon-Les-Mines has led to the identification of three predominantly marly units within the Middle and Upper Eocene of the Bassecq Syncline. The lowermost unit consists of bathyal marls, attributable to the Miretrain Marl Formation, and is of Late Lutetian - Early Bartonian age (NP 15b, NP 15c, NP 16 and base NP 17 ; EPA 9 to EPA 11 (? EPA12) and middle P 11 to top P 12). It is overlain by circalittoral, glauconitic indurate marls unknown up to now. This marly, intensely fractured unit, called the Bagats Marl Member, is defined to represent a new member within the Cote des Basques Marl Formation. It encompasses the Bartonian/Priabonian boundary sensu Berggren et al., 1995 (top NP 17 and base NP 18 ; EPA 13 and middle P 14). The uppermost unit is made up of fine sandy marls, containing several limestone intercalations towards the top. These Brihande Marls are included in the lower part of the Priabonian (NP 18, prohably up to the top of the section; EPA 13, EPA 14 and part of EPA 15, top P 14 and in part PIS). The succession of the Lespontes River is interpreted in terms of sequence stratigraphy, allowing refining its relationship within the Adour Basin. The integration of the data indicates that in Aquitaine the appearance of Chiasmolithus oamaruensis (base of zone NP 18) is prior to the appearance of Globigerinatheka semiinvoluta (base of zone PIS) and that nannofossil interval NP 19 - NP 20 is very difficult to identify in this area, due to the scarcity of the marker species lsthmolithus recurvus

A three-dimensional view of structural changes caused by deactivation of fluid catalytic cracking catalysts

Since its commercial introduction three-quarters of a century ago, fluid catalytic cracking has been one of the most important conversion processes in the petroleum industry. In this process, porous composites composed of zeolite and clay crack the heavy fractions in crude oil into transportation fuel and petrochemical feedstocks. Yet, over time the catalytic activity of these composite particles decreases. Here, we report on ptychographic tomography, diffraction, and fluorescence tomography, as well as electron microscopy measurements, which elucidate the structural changes that lead to catalyst deactivation. In combination, these measurements reveal zeolite amorphization and distinct structural changes on the particle exterior as the driving forces behind catalyst deactivation. Amorphization of zeolites, in particular, close to the particle exterior, results in a reduction of catalytic capacity. A concretion of the outermost particle layer into a dense amorphous silica–alumina shell further reduces the mass transport to the active sites within the composite

The “Historical Materials BAG”: A New Facilitated Access to Synchrotron X-ray Diffraction Analyses for Cultural Heritage Materials at the European Synchrotron Radiation Facility

The European Synchrotron Radiation Facility (ESRF) has recently commissioned the new Extremely Brilliant Source (EBS). The gain in brightness as well as the continuous development of beamline instruments boosts the beamline performances, in particular in terms of accelerated data acquisition. This has motivated the development of new access modes as an alternative to standard proposals for access to beamtime, in particular via the “block allocation group” (BAG) mode. Here, we present the recently implemented “historical materials BAG”: a community proposal giving to 10 European institutes the opportunity for guaranteed beamtime at two X-ray powder diffraction (XRPD) beamlines—ID13, for 2D high lateral resolution XRPD mapping, and ID22 for high angular resolution XRPD bulk analyses—with a particular focus on applications to cultural heritage. The capabilities offered by these instruments, the specific hardware and software developments to facilitate and speed-up data acquisition and data processing are detailed, and the first results from this new access are illustrated with recent applications to pigments, paintings, ceramics and wood

Involvement of the choroid plexus in Alzheimer’s disease pathophysiology: findings from mouse and human proteomic studies

Background: Structural and functional changes of the choroid plexus (ChP) have been reported in Alzheimer’s disease (AD). Nonetheless, the role of the ChP in the pathogenesis of AD remains largely unknown. We aim to unravel the relation between ChP functioning and core AD pathogenesis using a unique proteomic approach in mice and humans. Methods: We used an APP knock-in mouse model, APPNL-G-F, exhibiting amyloid pathology, to study the association between AD brain pathology and protein changes in mouse ChP tissue and CSF using liquid chromatography mass spectrometry. Mouse proteomes were investigated at the age of 7 weeks (n = 5) and 40 weeks (n = 5). Results were compared with previously published human AD CSF proteomic data (n = 496) to identify key proteins and pathways associated with ChP changes in AD. Results: ChP tissue proteome was dysregulated in APPNL-G-F mice relative to wild-type mice at both 7 and 40 weeks. At both ages, ChP tissue proteomic changes were associated with epithelial cells, mitochondria, protein modification, extracellular matrix and lipids. Nonetheless, some ChP tissue proteomic changes were different across the disease trajectory; pathways related to lysosomal function, endocytosis, protein formation, actin and complement were uniquely dysregulated at 7 weeks, while pathways associated with nervous system, immune system, protein degradation and vascular system were uniquely dysregulated at 40 weeks. CSF proteomics in both mice and humans showed similar ChP-related dysregulated pathways. Conclusions: Together, our findings support the hypothesis of ChP dysfunction in AD. These ChP changes were related to amyloid pathology. Therefore, the ChP could become a novel promising therapeutic target for AD