17 research outputs found

    Propiedades de durabilidad en concreto y análisis microestructural en pastas de cemento con adición de mucílago de nopal como aditivo natural

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    The present study evaluated the addition of a 3% nopal cactus mucilage solution to cement pastes, in its effects on setting times, flow, hydration, and microstructure, as well as on capillary water absorption and chloride diffusion in concrete. Hydration was characterized through XRD and microstructure was characterized with SEM. The mucilage solution/cement and water/cement ratios tested were 0.30, 0.45, and 0.60. The results in cement pastes indicate that the addition of mucilage increases setting times, reduces flow, slows cement hydration, and inhibits the formation of calcium hydroxide crystals in comparison with the control. Capillary absorption was significantly reduced in concrete containing mucilage, and chloride diffusion coefficients dropped up to 20% in the mixture with a mucilage/cement ratio = 0.30. The mixture with a mucilage/cement ratio = 0.45 displayed marginal reduction, and the mixture with mucilage/cement ratio = 0.60 exhibited a diffusion coefficient that was greater than the control for the specimens without moist curing.En esta investigación se evaluó el efecto de una solución de mucílago de nopal al 3% en los tiempos de fraguado, fluidez, hidratación y microestructura de pastas de cemento, y absorción capilar de agua y difusión de cloruros en concreto. La hidratación fue caracterizada por XRD y la microestructura por medio de SEM. Las relaciones solución de mucílago/cemento y agua/cemento fueron 0,30; 0,45 y 0,60. Los resultados en las pastas de cemento indican que el mucílago retarda los tiempos de fraguado, reduce la fluidez, retarda la hidratación del cemento, e inhibe la formación de cristales de hidróxido de calcio, comparados con los controles. La absorción capilar en concreto conteniendo mucílago se redujo significativamente y los coeficientes de difusión de cloruros disminuyeron hasta 20% en la mezcla mucílago/cemento = 0.30. En la relación mucílago/cemento = 0.45 la reducción fue marginal y en la relación mucílago/cemento = 0,60 el coeficiente de difusión fue mayor que el control para los especímenes sin curado en húmedo

    Fibrous Caps in Atherosclerosis Form by Notch-Dependent Mechanisms Common to Arterial Media Development.

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    Atheromatous fibrous caps are produced by smooth muscle cells (SMCs) that are recruited to the subendothelial space. We tested whether the recruitment mechanisms are the same as in embryonic artery development, which relies prominently on Notch signaling to form the subendothelial medial SMC layers. Notch elements were expressed in regions of fibrous cap in human and mouse plaques. To assess the causal role of Notch signaling in cap formation, we studied atherosclerosis in mice where the Notch pathway was inactivated in SMCs by conditional knockout of the essential effector transcription factor RBPJ (recombination signal-binding protein for immunoglobulin kappa J region). The recruitment of cap SMCs was significantly reduced without major effects on plaque size. Lineage tracing revealed the accumulation of SMC-derived plaque cells in the cap region was unaltered but that Notch-defective cells failed to re-acquire the SMC phenotype in the cap. Conversely, to analyze whether the loss of Notch signaling is required for SMC-derived cells to accumulate in atherogenesis, we studied atherosclerosis in mice with constitutive activation of Notch signaling in SMCs achieved by conditional expression of the Notch intracellular domain. Forced Notch signaling inhibited the ability of medial SMCs to contribute to plaque cells, including both cap SMCs and osteochondrogenic cells, and significantly reduced atherosclerosis development. Sequential loss and gain of Notch signaling is needed to build the cap SMC population. The shared mechanisms with embryonic arterial media assembly suggest that the cap forms as a neo-media that restores the connection between endothelium and subendothelial SMCs, transiently disrupted in early atherogenesis.This study was supported by a grant from the Ministerio de Ciencia e Innovación with cofunding from the European Regional Development Fund (SAF2016- 75580-R and PID2019-108568RB-I00 to J.F. Bentzon and SAF2016-78370-R to J.L. de la Pompa) and from the Novo Nordisk Foundation (NNF17OC0030688 to. J.F. Bentzon). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia e Innovación, and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015-0505).S

    Costs and benefits of automation for astronomical facilities

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    The Observatorio Astrof\'isico de Javalambre (OAJ{\dag}1) in Spain is a young astronomical facility, conceived and developed from the beginning as a fully automated observatory with the main goal of optimizing the processes in the scientific and general operation of the Observatory. The OAJ has been particularly conceived for carrying out large sky surveys with two unprecedented telescopes of unusually large fields of view (FoV): the JST/T250, a 2.55m telescope of 3deg field of view, and the JAST/T80, an 83cm telescope of 2deg field of view. The most immediate objective of the two telescopes for the next years is carrying out two unique photometric surveys of several thousands square degrees, J-PAS{\dag}2 and J-PLUS{\dag}3, each of them with a wide range of scientific applications, like e.g. large structure cosmology and Dark Energy, galaxy evolution, supernovae, Milky Way structure, exoplanets, among many others. To do that, JST and JAST are equipped with panoramic cameras under development within the J-PAS collaboration, JPCam and T80Cam respectively, which make use of large format (~ 10k x 10k) CCDs covering the entire focal plane. This paper describes in detail, from operations point of view, a comparison between the detailed cost of the global automation of the Observatory and the standard automation cost for astronomical facilities, in reference to the total investment and highlighting all benefits obtained from this approach and difficulties encountered. The paper also describes the engineering development of the overall facilities and infrastructures for the fully automated observatory and a global overview of current status, pinpointing lessons learned in order to boost observatory operations performance, achieving scientific targets, maintaining quality requirements, but also minimizing operation cost and human resources.Comment: Global Observatory Control System GOC

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    El estudio de arcillas españolas para su utilización como material de sellado en almacenamientos de residuos radiactivos: 20 años de progreso

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    [EN] The paper summarises the studies that have been performed in Spain as regards the selection and characterisation of clays suitable for sealing and backfilling of radioactive waste repositories. This research began in the 80’s under the auspices of ENRESA, the Spanish agency for nuclear waste management, and started by a survey of apt clay deposits and suppliers. The characterisation of the clays and the criteria followed for their further selection were those already accepted by the international community: mineralogical purity, retention properties, plasticity, low permeability, high swelling pressure and thermal conductivity. These initial studies resulted in the selection of deposits from the Cabo de Gata region (Almería) and the Tertiary Basin of Madrid (Toledo), whose detailed characterisation was carried out by several laboratories. The Cortijo de Archidona deposit (Almería) was finally selected and the bentonite taken there has been the object of various research projects that have ended in this bentonite being one of the best characterised from the mineralogical, thermal, hydraulic, mechanical, geochemical and alterability points of view. Besides, and more recently, the behaviour of the bentonite under the conditions of a repository has been studied at laboratory and natural scale, and the long-term evolution of the barrier is being analysed by natural analogues studies in the Cabo de Gata area.S[ES] El artículo resume los estudios que se han llevado a cabo en España para la selección y caracterización de arcillas aptas como material de sellado y relleno en almacenamientos de residuos radiactivos. La investigación comenzó en los años 80 bajo el patrocinio de ENRESA, la agencia española para la gestión de residuos nucleares, con la búsqueda de yacimientos de arcilla apropiados. El tipo de caracterización realizado y los criterios seguidos para la selección estaban ya aceptados por la comunidad internacional: pureza mineralógica, propiedades de retención, plasticidad, baja permeabilidad, elevada presión de hinchamiento y conductividad térmica. Estos estudios iniciales dieron lugar a la selección de yacimientos de la región de Cabo de Gata (Almería) y de la Cuenca Terciaria de Madrid (Toledo), cuya caracterización detallada fue realizada por varios laboratorios. Finalmente se seleccionó el yacimiento de Cortijo de Archidona (Almería), y la bentonita procedente de él ha sido objeto de varios proyectos de investigación que han hecho que esta bentonita sea una de las más intensamente caracterizadas en sus aspectos mineralógico, térmico, hidráulico, mecánico, geoquímico y de alterabilidad. Además, posteriormente se ha estudiado el comportamiento de esta bentonita en condiciones similares a las de un almacenamiento a escala de laboratorio y natural, y la posible evolución a largo plazo de la barrera se ha analizado mediante estudios de análogos naturales en la región de Cabo de Gata.This paper is dedicated to Pedro Rivas, a pioneer in the study of some of the issues herein presented and the head of many of the research projects compiled. He has participated intensely in all the described investigations. The useful suggestions and comments from the referees A. Meunier and R. Pusch have improved the paper and are gratefully acknowledged.Peer reviewe

    Focal therapy of prostate cancer index lesion with irreversible electroporation. A prospective study with a median follow-up of 3 years

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    Purpose: Our aim was to assess oncologic, safety, and quality of lifeerelated outcomes of focal therapy with irreversible electroporation in men with localized prostate cancer. Materials and Methods: This was a single-center, phase II study. Inclusion criteria: prostate cancer International Society of Urological Pathology grade 1-2, prostate specific antigen 15 ng/ml, cT2b. Patients were selected based on multiparametric magnetic resonance imaging and transperineal systematic and targeted magnetic resonance imagingeultrasound fusioneguided biopsy. Ablation of index lesions with safety margin was performed. Primary end point was cancer control, defined as the absence of any biopsy-proven tumor. A control transperineal biopsy was planned at 12 months and when suspected based on prostate specific antigen and/or multiparametric magnetic resonance imaging information. Quality of life was assessed using Expanded Prostate Cancer Index Composite Urinary Continence domain, International Index of Erectile Function, and International Prostate Symptom Score. Results: From November 2014 to July 2021, 41 consecutive patients were included with a median follow-up of 36 months. Thirty patients (73%) had International Society of Urological Pathology grade 1 tumors, 10 (24%) grade 2, and 1 (2.4%) grade 3. Recurrence was observed in 16 of 41 (39%) of the whole cohort, and 16 of 33 (48.4%) who underwent biopsy. In-field recurrence was detected in 5 (15%) and out-of-field in 11 (33.3%). Ten of 41 (24.6%) including 3 of 5 (60%) with in-field recurrences had significant tumors (Gleason pattern 4-5; more than 1 core or any >5 mm involved). Median recurrence-free survival was 32 months (95% CI 6.7-57.2). Twentysix patients (63.4%) were free from salvage treatment. All patients preserved urinary continence. Potency was maintained in 91.8%. Conclusions: Irreversible electroporation can achieve satisfactory 3-year in-field tumor control with excellent quality of life results in selected patients
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