44 research outputs found

    Temporary cable force monitoring techniques during bridge construction-phase: the Tajo River Viaduct experience

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    This article deals with the comparative analysis of current cable force monitoring techniques. In addition, the experience of three cable stress monitoring techniques during the construction phase is included: (a) the installation of load cells on the active anchorages of the cables, (b) the installation of unidirectional strain gauges, and (c) the evaluation of stresses in cables applying the vibrating wire technique by means of the installation of accelerometers. The main advantages and disadvantages of each technique analysed are highlighted in the Construction Process context of the Tajo Viaduct, one of the most singular viaducts recently built in Spain.This work has received funding from the European’s Union Horizon 2020 research and innovation program under the Grant Agreement No. 769373 (FORESEE project)

    Surfing in formal education: systematic review

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    Resumen: el objetivo del artículo fue realizar una revisión de los trabajos que estudiaron la práctica del surf dentro de la educación formal para conocer las iniciativas desarrolladas y resumir las orientaciones pedagógicas para su aplicación. Para ello, se realizó una revisión sistemática en las bases de datos Dialnet, Eric, SciELO, Scopus y Web of Science. Se recuperaron 12 documentos, publicados entre 2008 y 2018, desarrollados en cinco países diferentes y centrados en el surf, el bodyboard y el standup paddle. Dichos trabajos concluyeron que debe realizarse una aproximación progresiva al medio acuático y al surf en tres fases (centro educativo, piscina y playa), comenzando con la práctica del bodyboard por ser más fácil y menos peligrosa que el surf de tabla corta. Para las sesiones de piscina y playa, se recomienda utilizar el tiempo del recreo para los desplazamientos, ubicando las sesiones en las últimas horas de la jornada escolar. Los docentes de Educación Física que quieran implementar el surf en sus clases deberían adquirir conocimientos relacionados con la seguridad en el mar, con el equipamiento necesario para la práctica y con la propia técnica del surf.Abstract: the aim of this paper was to carry out a review of documents studying the surfing in formal education for discovering the programs developed and summarizing the pedagogical orientations for its application. Thus, a systematic review was performed in Dialnet, Eric, SciELO, Scopus and Web of Science databases. Twelve documents, published from 2008 to 2018, developed in five different countries and focused on surfing, bodyboarding and standup paddle, were retrieved. These documents concluded that a progressive approach to the aquatic environment and to surfing should be done in three phases (educational centre, swimming pool and beach), starting with the practice of bodyboard since it is easier and safer than shortboard surfing. The recess time should be used for travels in those sessions developed in the swimming pool and the beach. Moreover, these sessions should be scheduled in the last hours of the school day. Physical Education teachers willing to implement surfing in their sessions should gain knowledge about sea safety, surfing equipment and its own techniques

    Can statistical methods optimize complex multicomponent mixtures for sintering ceramic granular materials? A case of success with synthetic aggregates

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    The relationship between the proportions of multicomponent mixtures with the technological properties of ceramic granular materials (synthetic aggregates) has been studied using statistical methods. The four phases involved in the formulations have been: kaolin (K) as aluminosilicate source; cork powder (C) as organic carbon source; sodium carbonate (N) as flux and pyrite (P) as source of iron and sulfur. The Mixture Experiments - Design of Experiments (ME-DOE) has been the statistical methodology applied from the initial configuration of the 36 starting formulations to the final validation of the models and optimums. After granulation, artificial aggregates have been obtained by sintering in a rotary kiln, and their main technological properties have been determined. Bloating index (BI), particle density (ρrd), water absorption (WA24) and crushing strength (S) were selected as the four key characteristics to be modeled and optimized, using response surface and effect plots to assess the effect of K, C, N and P on such properties. 32 out of 36 starting varieties met the density criteria for lightweight aggregates. In the optimum formulations obtained, the minimum percentage of K was 83 wt%, so that the variations in the percentages of P, C and N were the critical variables for determining the final properties of the aggregate. The contrast between experimental and estimated data has shown that the models fit adequately, indicating that this type of approach may have enormous potential for future research on artificial aggregates and other ceramic materialsThis research was conducted as a part of the ECO-MET-AL Project, PID2019-109520RB-I00 / AEI / 10.13039/501100011033, “Can industrial and mining metalliferous wastes produce green lightweight aggregates? Applying the Circular Economy” funded by the Spanish Ministry of Science, Innovation and Universities and ERDF funds, framed in the “Ayudas a “Proyectos I + D + i" en el marco de los Programas Estatales de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I + D + i y de I + D + i orientada a los Retos de la Sociedad, Convocatoria 2019”. Thanks also to the SCAI of the University of Jaén, the University of Castilla-La Mancha and the University of Málaga for their service

    Analysis of the environmental degradation effects on the cables of La Arena bridge (Spain)

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    After nearly 25 years of service, some of the wires of the tendons of ?La Arena? bridge (Spain) started to exhibit the effects of environmental degradation processes. ?La Arena? is cable-stayed bridge with 6 towers and a reference span between towers of about 100 meters. After a maintenance inspection of the bridge, evidences of corrosion were detected in some of the galvanized wires of the cables. A more in-deep analysis of these wires revealed that many of them exhibited loss of section due to the corrosion process. In order to clarify the causes of this degradation event and to suggest some remedial actions, an experimental program was designed. This program consisted of tensile and fatigue tests on some strand samples of the bridge together with a fractographic analysis of the fracture surfaces of the wires, its galvanized layer thickness and some hydrogen measurements (hydrogen embrittlement could be another effect of the environmental degradation process).Once the type and extension of the flaws in the wires was characterized, a structural integrity assessment of the strands was performed with the aim of quantifying the margins until failure and establishing some maintenance recommendations

    A Peculiar Distribution of the Emerging Nematode Angiostrongylus cantonensis in the Canary Islands (Spain): Recent Introduction or Isolation Effect?

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    Angiostrongylus cantonensis is an emerging zoonotic nematode recognized as the leading cause of eosinophilic meningitis in the word. After its discovery in China, it was recorded in 30 countries worldwide. Recently, it has expanded to new areas such as South America and it has been recently found in the Atlantic island of Tenerife (Canary Islands). In order to characterize the distribution of A. cantonensis in the Canary Islands, the lungs of 1462 rodents were sampled in eight islands of the archipelago over 13 years and were then analyzed for A. cantonensis. Remarkably, the parasite was detected only in Tenerife, in Rattus rattus (19.7%) and Rattus norvegicus (7.14%). They were concretely in the northern part of the island, which had a warmer and more humid climate than the south and main cities. The absence of this nematode in other islands with similar environmental conditions could be explained by an isolation effect or by a recent introduction of the parasite in the islands. Besides, the presence in Tenerife of the most invasive lineage of A. cantonensis reinforced the hypothesis of a recent introduction on this island. This study highlights the need to implement control measures to prevent the expansion to other areas in order to avoid the transmission to humans and other animals

    Lipoprotein(A) Concentrations In Rheumatoid Arthritis On Biologic Therapy: Results From The Cardiovascular In Rheumatology [Carma] Study Project

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    Background Plasma concentrations of lipoprotein (a) (Lp(a)), a lipoprotein with atherogenic and thrombogenic properties, have a strong genetic basis, although high concentrations of Lp(a) have also been reported in the context of inflammation, as in rheumatoid arthritis (RA). Few studies evaluate the impact of biologic therapies (BT) on Lp(a) in RA, taking into account that with these new therapies a better control of inflammation is achieved. Objective The aim of the study was to evaluate the plasma concentrations of Lp(a) in Spanish RA patients on BT attending rheumatology outpatient clinics. Methods Baseline analysis of the CARdiovascular in rheuMAtology project, a 10-year prospective study, evaluating the risk of cardiovascular events in RA and other forms of inflammatory arthritis. RA patients were classified according to treatment: no biologic, anti-tumor necrosis factor, anti-interleukin-6 receptor tocilizumab (TCZ), and other biologic (rituximab or abatacept). A model of linear multivariate regression was built in which the dependent variable was Lp(a) concentration and the explanatory variable was BT. The model was adjusted for confounding factors. Results Seven hundred and seventy-five RA patients were analyzed. Plasma concentrations of total cholesterol and triglyceride were significantly higher in TCZ-treated patients. Nevertheless, no significant difference in the atherogenic index between TCZ-treated patients and patients without BT was found. After adjusting for confounding factors, patients with BT had lower concentrations of Lp(a) than those without BT; however, only TCZ-treated patients achieved statistically significant differences (?: ?0.303, 95% confidence interval: ?0.558 to ?0.047; P = .02). Conclusions RA patients treated with TCZ show lower plasma concentrations of Lp(a) compared with patients without BT.This project has been supported by an unrestricted grant from Abbvie, Spain. The design, analysis, interpretation of results, and preparation of the article have been done independently of Abbvie. Dr González-Gay's studies have been supported by grants from “Fondo de Investigaciones Sanitarias” PI06/0024, PS09/00748, and PI12/00060 and RD12/0009/0013 (RIER) from “Instituto de Salud Carlos III” (ISCIII) (Spain)

    Chemical Abundances from Inversions of Stellar Spectra: Analysis of Solar-Type Stars with Homogeneous and Static Model Atmospheres

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    Spectra of late-type stars are usually analyzed with static model atmospheres in local thermodynamic equilibrium (LTE) and a homogeneous plane-parallel or spherically symmetric geometry. The energy balance requires particular attention, as two elements which are particularly difficult to model play an important role: line blanketing and convection. Inversion techniques are able to bypass the difficulties of a detailed description of the energy balance. Assuming that the atmosphere is in hydrostatic equilibrium and LTE, it is possible to constrain its structure from spectroscopic observations. Among the most serious approximations still implicit in the method is a static and homogeneous geometry. In this paper, we take advantage of a realistic three-dimensional radiative hydrodynamical simulation of the solar surface to check the systematic errors incurred by an inversion assuming a plane-parallel horizontally-homogeneous atmosphere. The thermal structure recovered resembles the spatial and time average of the three-dimensional atmosphere. Furthermore, the abundances retrieved are typically within 10% (0.04 dex) of the abundances used to construct the simulation. The application to a fairly complete dataset from the solar spectrum provides further confidence in previous analyses of the solar composition. There is only a narrow range of one-dimensional thermal structures able to fit the absorption lines in the spectrum of the Sun. With our carefully selected dataset, random errors are about a factor of two smaller than systematic errors. A small number of strong metal lines can provide very reliable results. We foresee no major difficulty in applying the technique to other similar stars, and obtaining similar accuracies, using spectra with a resolving power about 50,000 and a signal-to-noise ratio as low as 30.Comment: 65 pages, figures included; uses aastex; to appear in The Astrophysical Journa

    Informe final del escaneo de horizonte sobre futuras especies exóticas invasoras en España

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    73 p.La introducción de especies exóticas invasoras (EEI) es una de las principales causas de la pérdida de biodiversidad a nivel global, que provoca grandes costes socioeconómicos. Sin embargo, el número de nuevas introducciones continúa creciendo año tras año. Por lo tanto, urge identificar posibles futuras EEI con el objetivo de diseñar e implementar medidas que prevengan y mitiguen los efectos negativos de su introducción. Así, el objetivo de este estudio es prospectar qué especies exóticas no establecidas en España podrían llegar fácilmente en los próximos 10 años, establecerse y causar importantes impactos ecológicos. Para ello, se ha realizado un escaneo de horizonte, siguiendo la metodología establecida en trabajos previos, siendo el primero para el conjunto de las especies exóticas invasoras en España. Se añadieron en el análisis especies que no son autóctonas de España, incluyendo los archipiélagos de Canarias y Baleares, y que no están establecidas en España. Un total de 39 científicos, expertos en distintos grupos taxonómicos y ecosistemas, ha evaluado 933 especies. Con el objetivo de analizar el acuerdo entre las evaluaciones individuales de los expertos y su consistencia, se llevaron a cabo dos análisis de fiabilidad complementarios, cuyos resultados se discuten en este informe. Como resultado del escaneo, se obtuvo una lista priorizada de 105 especies (46 con riesgo muy alto y 59 con riesgo alto). La mayoría de estas especies (84,8%), sin embargo, no están incluidas actualmente en el Catálogo Español de Especies Exóticas Invasoras. Por lo tanto, se recomienda la realización de un análisis de riesgo más detallado de estas especies y, si se confirma el riesgo alto, la solicitud de su incorporación en dicho catálogo o en el Listado de especies alóctonas susceptibles de competir con las especies silvestres autóctonas, alterar su pureza genética o los equilibrios ecológicos. Del mismo modo, se propone la realización de escaneos de horizonte específicos para los archipiélagos de Canarias y Baleares, ya que muchas de las especies autóctonas de la Península no lo son de las islas y podrían tener un gran impacto si allí se introdujeran. Este informe también analiza la afinidad taxonómica (i.e. filo) y funcional (i.e. productor primario, depredador, omnívoro, herbívoro o filtrador) de las especies de la lista priorizada, su origen geográfico y las principales vías de introducción. Por último, discute los mecanismos de impacto de dichas especies.Ministerio de Ciencia e Innovació

    Role of age and comorbidities in mortality of patients with infective endocarditis

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    [Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

    RICORS2040 : The need for collaborative research in chronic kidney disease

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    Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true
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