201 research outputs found

    Understanding the retreat of the Jurassic Cantabrian coast (N. Spain): Comprehensive monitoring and 4D evolution model of the Tazones Lighthouse landslide

    Get PDF
    [EN] Forecasting coastal dynamics and sea cliff retreat under different sea level rise scenarios requires a good understanding of the conditioning factors and their relative contribution to cliff stability. The so-called Jurassic Cantabrian Coast extends along 76 km of the coastline of the Asturias region (N Spain) and is well-known worldwide due to its paleontological heritage, in particular the presence of dinosaur remains and footprints. The abundance of stratigraphic, paleontological and tectonic studies contrasts with the scarcity of studies focused on the stability of this rocky coastline where cliffs predominate, sometimes exceeding 120 m in height. In fact, evidence of current and recent instability processes can be observed along the entire coastline. In this regard, continuous monitoring is crucial to understand ongoing instabilities in rocky coastlines, as in these settings some instabilities might initiate as slow movements that induce subtle topographic changes whose detection from either satellite or aerial imagery is problematic due to the spatial and temporal resolutions. This contribution presents a 4D evolution model of a key site, the Tazones Lighthouse landslide, located on the Cantabrian Coast of Asturias (N Spain), which affects subvertical rocky cliffs sculpted in the Jurassic bedrock made of alternating sandstone and marl. A high resolution multiapproach methodology was developed in order to understand its structure and kinematic characteristics, including: i) interpretation of aerial photographs and unmanned aerial photogrammetric surveys (UAV); ii) 22 monthly monitoring campaigns by total station; iii) 5 manual boreholes; iv) geomechanical characterization of the cliff bedrock; v) geomorphological evidence mapping; vi) analysis of landscape deformations obtained from UAV; and vii) precipitation, soil moisture and significant wave height (Hs) data analysis. The results show that the slope evolves by means of a complex-type mass movement, which combines translational and sliding mechanisms, and occupies tens of thousands of square meters. DTM and fieldwork analysis indicate that mass movement is mainly controlled by bedrock discontinuities (S0, 360/15-17; J1, 262/85; J2 166/75). The most important accelerations of slope movement correlate very well with rainfall, soil moisture and waves. Thus, the largest displacements occurring in January and October–November 2019, coincide with 2 periods of storms (maximum 24-h rainfall of 64.5 mm and 82.1 mm and maximum Hs of 6.54 and 9.09, respectively) and soil moisture values above 90%. Half of the markers moved more than 1 m and one of them exceeded 15 m. The 4D model obtained after the interpretation of the Tazones Lighthouse slope whole dataset, allows an understanding of how the surrounding cliffs have evolved in the past, fundamental to predicting their future behaviour.SIThis research is part of 1) the “COSINES” Project [CGL2017-83909-R], Call 2017 for RETOS Projects funded by the Spanish Economy, Industry and Competitiveness Ministry-Ministerio de Economía, Industria y Competitividad (MINECO), the Spanish Research Agency-Agencia Estatal de Investigación (AEI) and the European Regional Development Found (FEDER) and 2) the GEOCANCOSTA research group, supported by the Asturian Regional Government (Spain) [grant number GRUPIN-IDI-2018-184

    OPserver: interactive online-computations of opacities and radiative accelerations

    Full text link
    Codes to compute mean opacities and radiative accelerations for arbitrary chemical mixtures using the Opacity Project recently revised data have been restructured in a client--server architecture and transcribed as a subroutine library. This implementation increases efficiency in stellar modelling where element stratification due to diffusion processes is depth dependent, and thus requires repeated fast opacity reestimates. Three user modes are provided to fit different computing environments, namely a web browser, a local workstation and a distributed grid.Comment: 5 pages, 1 figur

    Las tobas/travertinos del barranco de Calabozo: Un ejemplo de construcción rápida de un edificio carbonático alimentado por una tubería de regadío

    Get PDF
    El barranco de Calabozo, en la Isla de Gran Canaria, muestra como rasgo excepcional la presencia de un edificio tobáceo/travertínico alimentado por una tubería de un sistema de regadío. La tubería se abasteció de pozos cuyas aguas son ricas en gases de origen volcánico y tienen temperaturas que alcanzan los 31ºC. En estas condiciones el agua se mineraliza con rapidez, enriqueciéndose en HCO3- y CO32-. Cuando sale de la tubería se desgasifica rápidamente (pierde el CO2) precipitando el carbonato que forma el edificio carbonático. El edificio del barranco de Calabozo es un edificio bioconstruido colgante, formado por: a) canal abastecedor (la tubería), b) pendiente c) barreras o cascadas y 4) pozas. El edificio funcionó escasas décadas y su tasa de crecimiento fue muy rápida. Esto explicaría los tres aspectos característicos de este edificio: 1) las barreras son bioconstrucciones de macrofitas, 2) las facies cristalinas gruesas son dominantes y responden a un desequilibrio fuerte por pérdida rápida de CO2 y 3) se observan rasgos diagéneticos a pesar de lo reciente que es el edificio. Las macrofitas ejercieron un papel de soporte para los precipitados inorgánicos, pero los microorganismos también jugaron un papel importante en la precipitación de las microfacies micríticas

    An Interpretation of Article 24 of the Constitution of Japan: Reconsidering the Principle of \u27\u27Gender Equality\u27\u27 from the Perspective of \u27\u27the Dilemma of Difference\u27\u27

    Get PDF
    This paper presents a novel methodology to calculate cation diffusion coefficients and activation energies in cubic Y2O3–ZrO2 by Molecular Dynamics. The calculation is based upon modulating the interaction potential to promote cation mobility within the lattice. The technique was calibrated by measuring static properties and oxygen self-diffusion characteristics, and then applied to cation diffusion. The respective activation energies and diffusion coefficients agree well with experimental findings. Preliminary results about grain boundary cation diffusion are presented for the first time as a proof of the potentiality of the procedureMinisterio de Ciencia e Innovación MAT2009-14351-C02-01, MAT2009-14351-C02-02Agencia Española de Cooperación Internacional y Desarrollo 53687

    Potential factors influencing the condition of demersal sharks in the Mediterranean deep sea ecosystems

    Get PDF
    The Alboran Sea and the Balearic Islands are two contrasting areas in terms of primary productivity. The former is among the most productive areas of the whole Mediterranean Sea, whereas the Balearic Islands is among the less productive ones in the western Mediterranean. The two areas also show different patterns in the bottom trawl fishing footprint. In the Alboran Sea, the fishing effort on the upper slope is much higher than in Balearic Islands. However, the opposite applies to the middle slope, the vast majority of it remaining unexploited in Alboran Sea, whereas a widespread fishery targeting blue and red shrimp Aristeus antennatus develops in Balearic Islands. Galeus melastomus is a small demersal shark species inhabiting slope bottoms, where adults and juveniles are segregated and concentrate in the middle and upper slope, respectively. It feeds intensively on mesopelagic preys which, in turn, feed on low trophic level organisms close to primary producers. In this work we aimed to study the effect of surface primary production on the condition of deep sea demersal communities. We compared the condition, diet and potential intra- and inter-species competition for feeding resources in the juveniles of G. melastomus between Alboran Sea and Balearic Islands. The comparisons of Le Cren’s relative condition factor, and hepatosomatic and digestivosomatic indices evidenced an opposite pattern to that a priori expectable: better condition in the less productive area. The analysis of stomach contents showed similar diets in both areas, but lower food ingestion in Alboran Sea than in Balearic Islands. Different abundances of potential intra- and inter-specific competitors for feeding resources in the two areas, apparently linked to the different fishing footprints, seems the most likely explanation for the better nourished individuals in Balearic Islands. Whereas juveniles of G. melastomus dominate the shark community in the Balearic Islands upper slope, where the presence of adults of this species is almost negligible, in Alboran Sea this stratum is dominated by adults and potential competitors of other small demersal shark species. All shark species together, including G. melastomus, showed abundances 38% higher in Alboran than in Balearic Islands. Our results show that condition of deep sea demersal fish is ruled by complex inter-relationships among different factors, needing the combination of biological, ecological and fisheries knowledge to understand its variability.En prensa2,42

    Role of Mitochondrial Complex IV in Age-Dependent Obesity

    Get PDF
    Aging is associated with progressive white adipose tissue (WAT) enlargement initiated early in life, but the molecular mechanisms involved remain unknown. Here we show that mitochondrial complex IV (CIV) activity and assembly are already repressed in white adipocytes of middle-aged mice and involve a HIF1A-dependent decline of essential CIV components such as COX5B. At the molecular level, HIF1A binds to the Cox5b proximal promoter and represses its expression. Silencing of Cox5b decreased fatty acid oxidation and promoted intracellular lipid accumulation. Moreover, local in vivo Cox5b silencing in WAT of young mice increased the size of adipocytes, whereas restoration of COX5B expression in aging mice counteracted adipocyte enlargement. An age-dependent reduction in COX5B gene expression was also found in human visceral adipose tissue. Collectively, our findings establish a pivotal role for CIV dysfunction in progressive white adipocyte enlargement during aging, which can be restored to alleviate age-dependent WAT expansion

    Overview of IFMIF-DONES diagnostics: Requirements and techniques

    Get PDF
    The IFMIF-DONES Facility is a unique first-class scientific infrastructure whose construction is foreseen in Granada, Spain, in the coming years. Strong integration efforts are being made at the current project phase aiming at harmonizing the ongoing design of the different and complex Systems of the facility. The consolidation of the Diagnostics and Instrumentation, transversal across many of them, is a key element of this purpose. A top-down strategy is proposed for a systematic Diagnostics Review and Requirement definition, putting emphasis in the one-of-a-kind instruments necessary by the operational particularities of some of the Systems, as well as to the harsh environment that they shall survive. In addition, other transversal aspects such as the ones related to Safety and Machine Protection and their respective requirements shall be also considered. The goal is therefore to advance further and solidly in the respective designs, identify problems in advance, and steer the Diagnostics development and validation campaigns that will be required. The present work provides an overview of this integration strategy as well as a description of some of the most challenging Diagnostics and Instruments within the facility, including several proposed techniques currently under study
    corecore