Calcite/aragonite ratio fluctuations in Aptian rudist bivalves: Correlation with changing temperatures

Understanding how bivalves responded to past temperature fluctuations may help us to predict specific responses of complex calcifiers to future climate change. During the late-Early Aptian, aragonite-rich rudist bivalves decreased in abundance in northern Tethyan carbonate platforms, while rudists with a thickened calcitic outer shell layer came to dominate those of Iberia. Seawater cooling and variations in calcium carbonate saturation states may have controlled this faunal turnover. However, our understanding of how rudist lineages responded to changing environmental conditions is constrained by a lack of quantitative data on the evolution of thickness, size, and mineralogy of the shell. This study is based on volumetric measurements of the shell and shows the transition in lineages of the family Polyconitidae from aragonite-rich mineralogy in the earliest Aptian, to low-Mg calcite-dominated mineralogy in the middle Aptian, returning to aragonite-dominated composition in the latest Aptian. The platform biocalcification crisis that occurred at the Early-Late Aptian boundary in the Tethys was marked by a relative increase of calcite and a decrease in skeletal thickness and commissural diameters. The highest calcite/aragonite (Cc/A) ratios in polyconitid rudists accompanied the late Aptian cold episode, and the lowest values were reached during the warmer intervals of the earliest and latest Aptian. These results imply a correlation between Cc/A ratio values and temperature and suggest that some bivalves adapted to less favorable calcification conditions by changing calcite and aragonite proportions of their bimineralic shells and decreasing skeletal thickness, thereby reducing the metabolic cost of shell growth. GeoRef Subjec

Chronostratigraphy of the Barremian-Early Albian of the Maestrat Basin (E Iberian Peninsula): integrating strontium-isotope stratigraphy and ammonoid biostratigraphy

A revised chronostratigraphy of the Barremian - Early Albian sedimentary record of the Maestrat Basin (E Iberian Peninsula) is provided based on a comprehensive synthesis of previous biostratigrahic data, a new ammonoid finding and numerical ages derived from 87Sr/86Sr values measured on shells of rudists, oysters and brachiopods. The succession, which comprises eight lithostratigraphic formations, is arranged into six major transgressive-regressive sequences and plotted against numerical ages, geomagnetic polarity chrons, ammonoid zones and the stratigraphic distribution of age-diagnostic ammonoids, orbitolinid fora- minifera and rudist bivalves. The oldest lithostratigraphic unit sampled, the marine Artoles Formation, is Early to Late Barremian. Above, the dinosaur-bearing deposits of the Morella Formation and its coastal to shallow-marine equivalent, the Cervera del Maestrat Formation, are of Late Barremian age and span at least part of the Imerites giraudi ammonoid zone. 87Sr/ 86Sr ratios from oyster shells in the upper part of the overlying marine Xert Formation are consistent with a latest Barremian-earliest Aptian age, while an ammonite belonging to the Late Barremian Martelites sarasini Zone was collected within the lowermost part of this lat- ter formation. The Barremian-Aptian boundary is tentatively placed close above the base of the succeeding transgressive marls of the Forcall Formation by analogy with nearby Tethyan basins, where major transgres- sive records contain latest Barremian ammonoids in their basal parts. The rest of the Forcall Formation and the platform carbonates of the Villarroya de los Pinares Formation are of Early Aptian age. The transition from the Barremian into the Aptian occurred in the course of a wide transgression, which was accompanied by the proliferation of Palorbitolina lenticularis. This transgressive event drowned Late Barremian carbonate platforms (Xert Formation) throughout the basin. Extensive carbonate platforms (Villarroya de los Pinares Formation) recovered coevally with a post-OAE 1a late Early Aptian major regression of relative sea level. The last lithostratigraphic unit analyzed, the marine Benassal Formation, spans the terminal Early Aptian- Late Aptian interval. Based on ammonite distributions, the lower part of the overlying coastal to continental coal-bearing Escucha Formation is Early Albian in age. This improved chronostratigraphic knowledge allows a more precise correlation of the sedimentary record studied with other coeval successions worldwide

KAP Degradation by Calpain Is Associated with CK2 Phosphorylation and Provides a Novel Mechanism for Cyclosporine A-Induced Proximal Tubule Injury

The use of cyclosporine A (CsA) is limited by its severe nephrotoxicity that includes reversible vasoconstrictor effects and proximal tubule cell injury, the latter associated whith chronic kidney disease progression. The mechanisms of CsA-induced tubular injury, mainly on the S3 segment, have not been completely elucidated. Kidney androgen-regulated protein (KAP) is exclusively expressed in kidney proximal tubule cells, interacts with the CsA-binding protein cyclophilin B and its expression diminishes in kidneys of CsA-treated mice. Since we reported that KAP protects against CsA toxicity in cultured proximal tubule cells, we hypothesized that low KAP levels found in kidneys of CsA-treated mice might correlate with proximal tubule cell injury. To test this hypothesis, we used KAP Tg mice developed in our laboratory and showed that these mice are more resistant to CsA-induced tubular injury than control littermates. Furthermore, we found that calpain, which was activated by CsA in cell cultures and kidney, is involved in KAP degradation and observed that phosphorylation of serine and threonine residues found in KAP PEST sequences by protein kinase CK2 enhances KAP degradation by calpain. Moreover, we also observed that CK2 inhibition protected against CsA-induced cytotoxicity. These findings point to a novel mechanism for CsA-induced kidney toxicity that might be useful in developing therapeutic strategies aimed at preventing tubular cell damage while maintaining the immunosuppressive effects of CsA

Using Sr isotopes and Rare Earth Elements to correlate sequences in regions with complex facies distributions: Example from the Late Cretaceous of the South-Central Pyrenees

Bathurst Meeting, 16th International Meeting of Carbonate Sedimentologists, 2019Understanding the distribution of carbonate facies in areas with complex structural histories can be challenging. The Upper Cretaceous deposits of the Sant Corneli and Boixols anticlines in the Pyrenees are controlled by extensional inherited structures and subsequent inversion. The aim of the present study is to understand the timing of the structures and correlate the facies across the anticlines. The dating of the Coniacian-Santonian postrift and Campanian- Maastrichtian syn-growth sequences is based on numerical ages derived from 87Sr/86Sr ratios. Additionally, elemental analysis and rare earth elements have been used to characterise seawater signatures, environments and diagenetic overprints. A total amount of 162 samples were collected across the two anticlines. Geochemical analysis by using ICP-MS permitted an evaluation of the elemental concentrations of the samples in order to discriminate the suitable ones for strontium isotopes. Numerical ages derived from strontium isotopes show that the Santonian carbonate systems were coetaneous across the Sant Corneli anticline. Rudist-rich facies in the northern flank of the Sant Corneli anticline correlate with the carbonate platforms in the southern flank. The uppermost Santonian shallow marine carbonates sampled in the southern flank in Collades de Basturs might correlate with the silty clays and marls of l’Aubagueta Member in the northern flank. The obtained numerical ages derived from strontium isotopes together with magnetostratigraphic, and biostratigraphic data have been used to constrain the timing of growth of the anticlines. The syn-growth succession shows ages ranging from middle Campanian in the uppermost Herbasavina Formation to early Maastrichtian in the Castell d’Orcau Unit. Those results point to older ages than previously published works. The analysis of rare earth elements and Yttrium (REEY) has shown flat shaped REEY profiles that are typical for the Late Cretaceous; and may indicate low diagenetic alteration. Preliminary results based on the Y/Ho ratio has revealed changes on paleobathymetries and environments. Therefore, the use of rare earth elements could be used as a proxy to support sedimentological observations

Promoción de la salud bucodental en el ámbito escolar : "programa aprende a sonreír" : propuesta didáctica

En port.: Secretaría General de Salud Pública y Participación. Consejería de Salud. Dirección General de Innovación Educativa. Consejería de Educación. Publicado en la página web de la Consejería de Salud: www.juntadeandalucia.es/salud (Consejería de Salud / Ciudadanía / Nuestra Salud / Vida sana / Salud bucodental / Materiales para la Salud Bucodental Infantil)YesEl Programa Aprende a Sonreír, trata de desarrollar hábitos saludables de higiene bucodental y alimentación sana, en niños y niñas de 3 a 12 años, con la implicación de familiares y profesionales de los centros educativos que desarrollan el Proyecto, a partir de diferentes recursos didácticos. Esta guía que desarrolla los contenidos educativos básicos del Programa "Aprende a Sonreír" a partir de una secuencia, que partiendo de la etapa de Educación Infantil hace un recorrido por cada uno de los tres ciclos de Educación Primaria. Estructura que parte de una metodología de desarrollo curricular en la que se apunta el tratamiento educativo desde distintos centros de interés y la transversalidad, como marco de referencia oportuno

Copernicus Marine Service Ocean State Report, Issue 3 Introduction

International audienc