Estudio comparativo experimental del comportamiento de uniones de cumbrera en cubiertas de madera laminada encolada con placas interiores de acero o tablero contrachapado de abedul

El presente trabajo tiene por objeto llevar a cabo un análisis experimental del comportamiento mecánico de ciertos sistemas planos de unión para elementos estructurales de madera laminada empleados en la construcción de cubiertas El estudio incluye los ensayos a escala real de seis din-teles a dos aguas de madera laminada, de 6 m de luz, 1 m de altura y una sección de 100 mm x 180 mm, sometidos a flexión en cuatro puntos. En tres dinteles el elemento de unión es una pieza de tablero contra-chapado de abedul, mientras que en los otros tres se ha utilizado un herraje de acero. La finalidad es valorar la posibilidad de sustituir los elementos de unión, realizados mediante herrajes, por otros constituidos por piezas de tablero contrachapado de abedul. Este objetivo se logra comparando el comportamiento resistente mostrado por ambos dispositivos de unión, y las deformaciones en cada caso de las estructuras completas. Los resultados resultaron muy satisfactorios tanto en la capacidad portante como en la rigidez de los dintele

Waste tire rubber particles modified by gamma radiation and their use as modifiers of concrete

En este trabajo se produjo concreto añadiendo hule de llantas de desecho, posteriormente se irradió con rayos gamma, para finalmente evaluar sus propiedades mecánicas. Los efectos de la radiación en el hule de llanta se evaluaron con diferentes técnicas analíticas.in this work, cement concrete specimens were produced with cement, water, rock crushed and sand; this last was partially substituted by particles of waste tire rubber. Then the compression properties of the specimens were evaluated following the experimental parameters: a) gamma irradiation dose (200, 250 and 300 kGy), b) particle size of tire rubber (0.85 and 2.8 mm), and c) particulate concentration of tire rubber (1, 3 and 5 wt. %). In addition, the mechanical compression results were related with the changes on the physicochemical properties of the irradiated tire particles, which were analyzed by FT-IR, Raman, UV–vis, SEM, XRD, TGA and DSC

SISTEMA DE MEDIÇÃO DA QUALIDADE DA EDUCAÇÃO FÍSICA NO CHILE E SUA INFLUÊNCIA NA REALIDADE ESCOLAR

El actual SIMCE-EF (Sistema de Medición de la Calidad de la Educación Física), evalúa componentes de la condición física, que poco tienen que ver con los objetivos de la disciplina. El objetivo es determinar la influencia percibida por los docentes a sus prácticas educativas y en el entorno escolar, atribuida a la aplicación de la prueba SIMCE-EF. Se encuestan y entrevistan a 17 profesores de EF, pertenecientes al 100%  de los establecimientos de la Comuna de  Viña del Mar, Chile, que se les aplicó el SIMCE-EF en los años, 2010, 2011 y 2012. Según los docentes, la prueba no tiene impacto en el ámbito escolar, lo que podría mantener los resultados en las aplicaciones futuras, mientras se evalúe solo la  condición física y en un formato piloto. The current SIMCE-EF (Measurement System Quality Physical Education), which measures certain fitness components, has little to do with the learning goals of the discipline. The objective of this study is to determine how the SIMCE-EF exam's influence is perceived by teachers in relation to their own teaching performance and the school environment. Seventeen P.E teachers participated in surveys and were interviewed, which is a hundred percent of the public system personnel in the area working in Viña del Mar, where the exams were given in 2010, 2011, and 2012. According to the teachers, this exam has no impact on the school environment and such results can remain in the future as long  as SIME-EF only measures overall physical fitness in a pilot format. O atual SIMCE-EF (Sistema de Medição da Qualidade da Educação Física) avalia os componentes da condição física que pouco tem a ver com os objetivos da disciplina de educação física. O objetivo deste trabalho é determinar a influência percebida pelos professores para as suas práticas educativas e do ambiente escolar, atribuídos à implementação do teste SIMCE-EF. Foram  entrevistados 17 professores de Educação Física, pertencentes a 100% do município de Viña del Mar (Chile) que se lhes aplicou o SIMCE-EF, nos anos de 2010, 2011 e 2012. Segundo os docentes, os resultados encontrados indicam que SIMCE-EF, não apresentam impacto no âmbito escolar. Este resultado poderia assegurar resultados em aplicações futuras, sempre que se avalie somente a condicao fisica em formato de estudo piloto.

Boosting mitochondria activity by silencing MCJ overcomes cholestasis-induced liver injury

Background & Aims: Mitochondria are the major organelles for the formation of reactive oxygen species (ROS) in the cell, and mitochondrial dysfunction has been described as a key factor in the pathogenesis of cholestatic liver disease. The methylation-controlled J-protein (MCJ) is a mitochondrial protein that interacts with and represses the function of complex I of the electron transport chain. The relevance of MCJ in the pathology of cholestasis has not yet been explored. Methods: We studied the relationship between MCJ and cholestasis-induced liver injury in liver biopsies from patients with chronic cholestatic liver diseases, and in livers and primary hepatocytes obtained from WT and MCJ-KO mice. Bile duct ligation (BDL) was used as an animal model of cholestasis, and primary hepatocytes were treated with toxic doses of bile acids. We evaluated the effect of MCJ silencing for the treatment of cholestasis-induced liver injury. Results: Elevated levels of MCJ were detected in the liver tissue of patients with chronic cholestatic liver disease when compared with normal liver tissue. Likewise, in mouse models, the hepatic levels of MCJ were increased. After BDL, MCJ-KO animals showed significantly decreased inflammation and apoptosis. In an in vitro model of bile-acid induced toxicity, we observed that the loss of MCJ protected mouse primary hepatocytes from bile acid-induced mitochondrial ROS over-production and ATP depletion, enabling higher cell viability. Finally, the in vivo inhibition of the MCJ expression, following BDL, showed reduced liver injury and a mitigation of the main cholestatic characteristics. Conclusions: We demonstrated that MCJ is involved in the progression of cholestatic liver injury, and our results identified MCJ as a potential therapeutic target to mitigate the liver injury caused by cholestasis. Lay summary: In this study, we examine the effect of mitochondrial respiratory chain inhibition by MCJ on bile acid-induced liver toxicity. The loss of MCJ protects hepatocytes against apoptosis, mitochondrial ROS overproduction, and ATP depletion as a result of bile acid toxicity. Our results identify MCJ as a potential therapeutic target to mitigate liver injury in cholestatic liver diseases.Acknowledgements: We thank MINECO for the Severo Ochoa Excellence Accreditation of CIC bioGUNE [SEV-2016-0644]

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

Testing the profitability of Anaerobic Digestion in a large-scale UK dairy farm

Anaerobic Digestion (AD) consists in the transformation of any organic non-woody material by micro-organisms into biogas. This biogas, composed of approximately 60 per cent methane can be further burnt and converted into electricity and heat. The UK’s livestock agricultural sector has tremendous potential to take advantage of this technology, as it produces over 150 million tonnes of animal manure annually. This is a commonly used input to feed anaerobic digestion plants. Furthermore, AD brings additional benefits to the farming community, as it is an environmentally friendly waste management option, and a cost-effective fertiliser production method. The Government’s commitment to the development of AD is portrayed by the recent increase in Feed-In Tariffs, a set price determined by the Ministry of Energy and Climate Change and paid by the energy supplying companies for every unit of electricity generated through renewable sources. This paper tests the economics, return on investment, and overall value of installing and operating a 500kWe anaerobic digestion plant in a large scale UK dairy farm. A discounted cash flow analysis was the utilised method to quantify the farm business value and profitability, and understand how attractive an investment of this type would be for a UK large-scale dairy farmer