Reconstructing a Carboniferous inferred coral–alcyonarian association using a biomineralogical approach

The taxonomic assignation and ecological implications of the genus Syringoalcyon Termier & Termier, 1945 have been a palaeontological problem for a long time. Carboniferous material from Morocco and Spain has been studied using a biomineralogical approach by means of petrographic microscopy, SEM, AFM, EMPA and CIP microscopy analysis. Detailed morphological, structural, chemical composition and crystallographic data enable a deeper understanding of the nature of Syringoalcyon. The coral walls and the so-called epithecal scales exhibit conspicuous differences in microstructure (lamellae and holacanthine fibres in the coral vs. single crystal in scales), nanostructure (pill-shaped vs. granule-shaped nanocrystals), composition (LMC vs. HMC) and crystallographic orientation. The results of these analyses imply that Syringoalcyon is an association between the tabulate coral Syringopora and an epibiont. They also suggest that the epibiont was an alcyonarian (a rare occurrence in the fossil record) that was attached to the syringoporoid. This work highlights the utility of the biomineralizational approaches for solving palaeontological problems, such as systematic affinities, and for advancing knowledge of the evolution of biocrystallization processes.Financial support through the Spanish Ministerio de Economía y Competitividad (research project CGL2012-30922BTE) and Complutense University Research Group (910231). Ismael Coronado acknowledges financial support through a FPI-UCM grant and the Synthesys grant FR-TAF-2397 developed in MNHN (Paris, France).Peer reviewe

Biochemical and mutational studies of allantoinase from Bacillus licheniformis CECT 20T.

Allantoinases (allantoin amidohydrolase, E.C. 3.5.2.5) catalyze the hydrolysis of the amide bond of allantoin to form allantoic acid, in those organisms where allantoin is not the final product of uric acid degradation. Despite their importance in the purine catabolic pathway, sequences of microbial allantoinases with proven activity are scarce, and only the enzyme from Escherichia coli (AllEco) has been studied in detail in the genomic era. In this work, we report the cloning, purification and characterization of the recombinant allantoinase from Bacillus licheniformis CECT 20T (AllBali). The enzyme was a homotetramer with an apparent Tm of 62 ± 1 °C. Optimal parameters for the enzyme activity were pH 7.5 and 50 °C, showing apparent Km and kcat values of 17.7 ± 2.7 mM and 24.4 ± 1.5 s−1, respectively. Co2+ proved to be the most effective cofactor, inverting the enantioselectivity of AllBali when compared to that previously reported for other allantoinases. The common ability of different cyclic amidohydrolases to hydrolyze distinct substrates to the natural one also proved true for AllBali. The enzyme was able to hydrolyze hydantoin, dihydrouracil and 5-ethyl-hydantoin, although at relative rates 3–4 orders of magnitude lower than with allantoin. Mutagenesis experiments suggest that S292 is likely implicated in the binding of the allantoin ring through the carbonyl group of the polypeptide main chain, which is the common mechanism observed in other members of the amidohydrolase family. In addition, our results suggest an allosteric effect of H2O2 toward allantoinase.pre-print829 K

Biochemical and Mutational Studies of the Bacillus cereus CECT 5050T Formamidase Support the Existence of a C-E-E-K Tetrad in Several Members of the Nitrilase Superfamily.

Formamidases (EC 3.5.1.49) are poorly characterized proteins. In spite of this scarce knowledge, ammonia has been described as playing a central role in the pathogenesis of human pathogens such as Helicobacter pylori, for which formamidase has been shown to participate in the nitrogen metabolic pathway. Sequence analysis has revealed that at least two different groups of formamidases are classified as EC 3.5.1.49: on the one hand, the derivatives of the FmdA-AmdA superfamily, which are the best studied to date, and on the other hand, the derivatives of Helicobacter pylori AmiF. Here we present the cloning, purification, and characterization of a recombinant formamidase from Bacillus cereus CECT 5050T (BceAmiF), the second member of the AmiF subfamily to be characterized, showing new features of the enzyme further supporting its relationship with aliphatic amidases. We also present homology modeling-based mutational studies confirming the importance of the Glu140 and Tyr191 residues in the enzymatic activities of the AmiF family. Moreover, we can conclude that a second glutamate residue is critical in several members of the nitrilase superfamily, meaning that what has consistently been identified as a C-E-K triad is in fact a C-E-E-K tetrad.pre-print615 K

Corales tabulados del Ordovícico (Caradoc) de la Precordillera Argentina.

En este estudio se describen por primera vez dos corales tabulados del Ordovícico de la Precordillera Argentina. Se trata de un ejemplar asignado a aff. Paleofavosites sp., procedente de la formación Las Aguaditas y otro clasificado como ?Billingsaria sp., procedente de la Formación Las Plantas, ambos del Caradoc. La escasez del material y detalles problemáticos de su microestructura en el primero de los casos y la mala preservación en el segundo impiden llegar a determinaciones taxonómicas más precisas. [ABSTRACT] This study deals with the description of two Ordovician tabulate corals from Argentine Precordillera. This is the first description of Ordovician tabulate corals in Argentina. They are one specimen of aff. Paleofavosites sp., from the Las Aguaditas Formation and another specimen of ?Billingsaria sp., from the Las Plantas Formation, both Caradoc in age. The scarcity of the material and problematic microstructural details in the first case and the bad preservation of the specimen in the second case impede more precise identifications

Sedimentación de plataforma interna-externa con desarrollo de montículos en el Viseense del sector central de la Sierra de la Estrella (Carbonífero, Córdoba)

En la Sierra de la Estrella (Área del Guadiato, Córdoba) se localiza una sucesión del Viseense superior, principalmente carbonatada, con desarrollo de montículos tipo mud-mound. En esta zona predominan calizas bioclásticas, brechoideas y bioconstruidas, aunque también se localizan niveles de areniscas y conglomerados. Se han identificado un total de 7 litofacies que agrupan a su vez a 9 microfacies tipo: 1.–Mudstonewackestone con cavidades estromatactoideas y fábricas fenestrales, 2.–Wackestonepackstone con algas y bioclastos, 3.1.–Packstone de pseudopeloides, 3.2.–Packstone con algas, pseudopeloides y litoclastos, 4.1.–Packstone de briozoos y crinoideos, 4.2.–Packstone con algas y espículas, 5.–Packstone-rudstone de litoclastos, 6.–Grainstone de cortoides y litoclastos, 7.–Arenitas híbridas. El ambiente de sedimentación se interpreta como una zona de transición entre rampa interna y externa carbonática con influencia de terrígenos y desarrollo de montículos microbianos. [ABSTRACT] Late Viséan calcareous rocks containing buildups occur in the Sierra de la Estrella, Guadiato Valley. Bioclastic, breccioid and biohermal limestones as well as sandstones and conglomerates occur. Lithofacies analysis allow to identify 7 types, with 9 characteristic microfacies: 1.–Micropeloidal mudstone-wackestone with stromatactoid cavities and fenestral fabrics, 2.–Algal-bioclastic wackestone-packstone, 3.1.–Pseudopeloidal packstone, 3.2.–Packstone with algae, pseudopeloids and lithoclast, 4.1.–Bryozoal-crinoidal packstone, 4.2.–Packstone with algae and sponge spiculae, 5.–Packstone-rudstone with lithoclasts, 6.–Cortoid-lithoclasts grainstone, 7.–Hybrid sandstones. Sediments are attributed to a inner to outer carbonate ramp with sporadic terrigenous influence. Some microbial mounds developed in such environment

Diseño preliminar de una estación terrena basada en software radio para aplicaciones docentes

Most of student satellite missions are based on the design, construction and launch of a picosatellite (cubesat) including the design of the ground station (GS). Traditional GS are based on commercial elements and are designed to support only one mission. These stations access the mission data very inefficiently, as only contact the satellite during short visibility periods. In this paper, we present a novel GS concept based on software defined radio technology that can be integrated in a global network for satellite tracking. The station will be implemented by a group of students as a part of a space project under the supervision of a faculty coordinator. The design must fulfil the requirements of low cost, remote operation, and flexibility to operate in different frequency bands. The set-up of this mid-term educational space project to build an operational GS will hopefully motivate Telecommunication Engineering students to participate and gain real hands-on experience in an international space environment

Religious confessions and public aids through fundación pluralismo y convivencia: beneficiaries, work lines and projects

En el presente trabajo analizaremos la cuestión de la cooperación económica del Estado con las confesiones religiosas, determinando cuál es el criterio normativo que constitucionalmente justifica, y en conclusión permite, que el Estado establezca relaciones económicas de cooperación con las comunidades religiosas en forma de financiación directa. A raíz de esta premisa nos centraremos en el estudio de la financiación de las confesiones minoritarias, teniendo en cuenta la financiación directa de la Iglesia Católica, mediante el análisis de la Fundación Pluralismo y Convivencia, iniciativa estatal nacida hace ya 12 años, desde su origen hasta cómo desarrollan las líneas de concesión de ayudas. Finalmente, conoceremos si de manera efectiva las confesiones minoritarias están accediendo a ayudas públicas que nos permitan hablar de una auténtica financiación estatal directa de sus actividades.In this paper we analyze the issue of economic cooperation of the state with religious confessions, determining which is the normative approach that constitutionally justified, and in conclusion allows, the State to establish economic cooperation relations with religious communities in the form of direct funding. Following this premise we will focus on the study of the funding of minority confessions, taking into account the direct funding of the Catholic Church, through analysis of the Pluralism and Coexistence Foundation, state initiative born 12 years ago, in which we will study from origin to how to develop the lines for granting aid. Finally, we will know if effectively minority religions are accessing to public subsidies that allow us to speak of a true direct state funding of their activities.Máster Universitario en Acceso a la Profesión de Abogado (M155

Mechanism of action of a Janus-faced single-domain protein inhibitor simultaneously targeting two peptidase classes

Protein inhibitors provide a physiological mechanism for the regulation of proteolytic enzymes. While most single-domain inhibitors have one reactive site with which they target peptidases of a specific catalytic class, selected specimens inhibit two peptidase molecules simultaneously, thus giving rise to ternary complexes. To study such inhibition, we analyzed the function of one of these proteins, sermetstatin, which strongly binds as a dimer to serine proteinases (SPs) and a metallopeptidase (MP). In addition, we determined the structures of the isolated inhibitor dimer and its heterotetrameric complexes with the SP subtilisin and the MP snapalysin, which reveal that inhibition occurs through two independent distal reactive sites. These structures and the derived model for the heterohexameric complex provide for the first time a detailed view of the molecular mechanism of simultaneous inhibition of proteinases belonging to two distinct mechanistic classes by a single-domain protein. © The Royal Society of Chemistry 2013.Peer Reviewe

Diseño de actividades autónomas en DGPad para producir aprendizaje asociado al valor posicional

La emergencia sanitaria ha transformado los procesos de enseñanza-aprendizaje. Por ejemplo, el tiempo se convirtió en un factor crucial, ya que se redujeron los espacios de interacción docente-estudiante. Las prácticas educativas caracterizadas por trabajar colectivamente y usar material manipulativo se volvieron obsoletas, dadas las condiciones. Surge entonces la necesidad de aprovechar el potencial de los medios tecnológicos teniendo en cuenta los efectos que producen en el aprendizaje de los estudiantes. La propuesta se centra en el desarrollo de actividades en el software DGPad que permiten al estudiante adquirir nuevos conocimientos sin la intervención del profesor. Se busca utilizar el potencial de las herramientas disponibles en el software que permiten automatizar, desde las retroacciones matemáticas y didácticas, actos de devolución que movilicen al estudiante a aceptar y comprender el problema, controlando procesos intermedios y validando sus respuestas, todo en el marco de la interacción del estudiante con el software

Burnout, Resilience, and COVID-19 among Teachers: Predictive Capacity of an Artificial Neural Network

Emotional exhaustion, cynicism, and work inefficiency are three dimensions that define burnout syndrome among teachers. On another note, resilience can be understood as the ability to adapt to the environment and overcome adverse situations. In addition, COVID-19 has provided a threatening environment that has led to the implementation of resilience strategies to struggle with burnout and cope with the virus. The aim of this study was to analyze the relationship between resilience, burnout dimensions, and variables associated with COVID-19 through the design of an artificial neural network architecture. For this purpose, the Maslach Burnout InventoryGeneral Survey (MBI-GS), the Brief Resilience Coping Scale (BRCS), and a questionnaire on stress towards COVID-19 were administered to 419 teachers from secondary schools in southeastern Spain (292 females; 69.7%). The results showed that 30.8% suffered from burnout (high emotional exhaustion, high cynicism, and low professional efficacy) and that 38.7% had a high level of resilience, with an inverse relationship between both constructs. Likewise, we modelled an ANN able to predict burnout syndrome among 97.4% of teachers based on its dimensions, resilience, sociodemographic variables, and the stress generated by COVID-19. Our conclusions shed some light on the efficacy of relying on artificial intelligence in the educational field to predict the psychological situation of teachers and take early action