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The study of neutron-induced reactions is of high relevance in a wide variety of fields, ranging from stellar nucleosynthesis and fundamental nuclear physics to applications of nuclear technology. In nuclear energy, high accuracy neutron data are needed for the development of Generation IV fast reactors and accelerator driven systems, these last aimed specifically at nuclear waste incineration, as well as for research on innovative fuel cycles. In this context, a high luminosity Neutron Time Of Flight facility, n_TOF, is operating at CERN since more than a decade, with the aim of providing new, high accuracy and high resolution neutron cross-sections. Thanks to the features of the neutron beam, a rich experimental program relevant to nuclear technology has been carried out so far. The program will be further expanded in the near future, thanks in particular to new highflux experimental area, now under construction.

Changes in the physicochemical composition of wine vinegars produced by submerged culture system and aged in wood were followed. Five Sherry wine vinegars and a model vinegar solution were aged in six new American oak butts of 16.6 L capacity. A total of 24 phenolic compounds were monitored during the maturation study (24 months), along with other physicochemical parameters (total extract, acidity, residual alcohol and total phenolic index). Multivariate statistical analysis was applied to the data. From the sixth month on, significant changes were produced in most of the phenolic compounds, mainly aromatic aldehydes and 5-(hydroxymethyl)-2-furaldehyde. When all the phenolic compounds were considered as variables, cluster analysis grouped samples according to the wine substrate employed in the elaboration of vinegars under study. Within each subcluster, samples are arranged according to their aging status when phenolic compounds accounting significative changes at 180 days of aging are considered. Discriminant functions were constructed from the phenolic compounds data set. The validity of these functions was tested using 13 samples of aged commercial Sherry wine vinegars and 25 unaged vinegars. A total of 97.4% of the test samples was correctly classified within its respective group.

A comprehensive assessment of indoor environmental conditions is performed on a representative sample of classrooms in schools across southern Spain (Mediterranean climate) to evaluate the thermal comfort level, thermal perception and preference, and the relationship with HVAC systems, with a comparison of seasons and personal clothing. Almost fifty classrooms were studied and around one thousand pool-surveys distributed among their occupants, aged 12 to 17. These measurements were performed during spring, autumn, and winter, considered the most representative periods of use for schools. A new proposed protocol has been developed for the collection and subsequent analysis of data, applying thermal comfort indicators and using the most frequent predictive models, rational (RTC) and adaptive (ATC), for comparison. Cooling is not provided in any of the rooms and natural ventilation is found in most of the spaces during midseasons. Despite the existence of a general heating service in almost all classrooms in the cold period, the use of mechanical ventilation is limited. Heating did not usually provide standard set-point temperatures. However, this did not lead to widespread complaints, as occupants perceive the thermal environment as neutral—varying greatly between users—and show a preference for slightly colder environments. Comparison of these thermal comfort votes and the thermal comfort indicators used showed a better fit of thermal preference over thermal sensation and more reliable results when using regional ATC indicators than the ASHRAE adaptive model. This highlights the significance of inhabitants’ actual thermal perception. These findings provide useful insight for a more accurate design of this type of building, as well as a suitable tool for the improvement of existing spaces, improving the conditions for both comfort and wellbeing in these spaces, as well as providing a better fit of energy use for actual comfort conditions.

Urban population growth together with energy demand increase, among other consequences, provokes the augment of greenhouse gasses emissions (GGE), which contribute to Climate Change. Energy efficiency in buildings becomes essential to reduce demand, keeping acceptable comfort levels for users. Office, housing and commercial buildings consume more than one third of the primary energy produced in Argentina, a similar percentage worldwide. New digital technologies to afford this complex problem combine architectural design and building energy modelling (BEM), like parametric architecture. This tool enables complex tasks as energy efficient building design where materials, energy and information must be considered simultaneously. All these variables can be gathered into one unique transparent process, putting forward energy demand as a key factor for conceptual design decisions. In this paper, we compare the heating demand for one typical winter day with the demand of a house audited by our Laboratory, in order to calibrate our model. The audit shows the results before and after energy efficiency refurbishment. We also calculate the cooling demand for one typical summer day for a future comparison with the audited building. El crecimiento de la población urbana con el aumento de la demanda energética, entre otras consecuencias, provoca la suba de las emisiones de gases de efecto invernadero (GEI) que contribuyen al Cambio Climático. La eficiencia energética en los edificios es imprescindible para reducir dicha demanda manteniendo niveles de confort aceptables para el usuario. Los edificios destinados a uso residencial, comercial y administrativo consumen más de un tercio de la energía primaria producida en Argentina, porcentaje similar al resto del mundo. Las nuevas tecnologías digitales para solucionar este problema combinan la proyectación arquitectónica con la simulación de la performance energética, entre ellas, el diseño paramétrico. Este se ha transformado en una valiosa herramienta para encarar tareas complejas como ser el diseño de edificios eficientes, donde se requiere considerar materiales, energía e información. Este procedimiento permite reunir todas estas variables en un único proceso transparente, haciendo de la demanda energética una cuestión determinante en las decisiones proyectuales tempranas. En este trabajo se comparan la demanda en calefacción de un día típico de invierno con la demanda obtenida a partir de una vivienda energéticamente rehabilitada auditada por nuestro Laboratorio, a fin de calibrar el nuevo modelo. Asimismo se calcula la demanda de refrigeración para su posterior comparación con el edificio auditado.

Abstract This paper presents a control strategy for sun trackers which adapts continuously to different sources of error, avoiding the necessity of any kind of calibration by analyzing the produced electric power to sense the position of the Sun. The proposed strategy is able to meet the strict specifications for HCPV sun trackers despite of mechanical uncertainties (misalignments in the structure itself, misalignment of the solar modules with respect to the wing, etc.) and installation uncertainties (misalignments of the platform with respect to geographical north). Experimental results with an industrial-grade solar tracker showing the validity of the proposed control strategy under sunny and moderate cloudy conditions, as well as with different installation precisions by un-calibrating the system on purpose are exposed.

Profitability studies are needed to establish the potential pathways required for viable biomethane production in the Brandenburg region of Germany. This work study the profitability of a potential biomethane production plant in the eastern German region of Brandenburg, through a specific practical scenario with data collected from a regional biogas plant located in Alteno (Schradenbiogas GmbH & Co. KG). Several parameters with potential economic influence such as distance of the production point to the grid, waste utilization percentage, and investment, were analyzed. The results illustrate a negative overall net present value with the scenario of no governmental investment, even when considering trading the CO2 obtained throughout the process. Subsidies needed to reach profitability varied with distance from 13.5 €/MWh to 19.3 €/MWh. For a fixed distance of 15 kms, the importance of percentage of waste utilization was examined. Only 100% of waste utilization and 75% of waste utilization would reach profitability under a reasonable subsidies scheme (16.3 and 18.8 €/MWh respectively). Concerning the importance of investment, a subsidized investment of at least 70% is demanded for positive net present values. Besides, the sensitivity analysis remarks the energy consumption of the biogas upgrading stage, the electricity price, and the energy consumption of biogas production as major parameters to be tackled for the successful implementation of biogas upgrading plants. The results here obtained invite to ponder about potential strategies to further improve the economic viability of this kind of renewable projects. In this line, using the CO2 separated to produce added-value chemicals can be an interesting alternative.

AbstractBinge drinking (BD) is an especially pro‐oxidant pattern of alcohol consumption, particularly widespread in the adolescent population. In the kidneys, it affects the glomerular filtration rate (GFR), leading to high blood pressure. BD exposure also disrupts folic acid (FA) homeostasis and its antioxidant properties. The aim of this study is to test a FA supplementation as an effective therapy against the oxidative, nitrosative, and apoptotic damage as well as the renal function alteration occurred after BD in adolescence. Four groups of adolescent rats were used: control, BD (exposed to intraperitoneal alcohol), control FA‐supplemented group and BD FA‐supplemented group. Dietary FA content in control groups was 2 ppm, and 8 ppm in supplemented groups. BD provoked an oxidative imbalance in the kidneys by dysregulating antioxidant enzymes and increasing the enzyme NADPH oxidase 4 (NOX4), which led to an increase in caspase‐9. BD also altered the renal nitrosative status affecting the expression of the three nitric oxide (NO) synthase (NOS) isoforms, leading to a decrease in NO levels. Functionally, BD produced a hydric‐electrolytic imbalance, a low GFR and an increase in blood pressure. FA supplementation to BD adolescent rats improved the oxidative, nitrosative, and apoptotic balance, recovering the hydric‐electrolytic equilibrium and blood pressure. However, neither NO levels nor GFR were recovered, showing in this study for the first time that NO availability in the kidneys plays a crucial role in GFR regulation that the antioxidant effects of FA cannot repair.

Abstract Rational function-based models have proved to be very efficient for accurate frequency-dependent modeling of power system components. These models are able to characterize the components terminal behaviours (analysing the admittance matrix) for nodal analysis. This provides a fast convergence and inherent stability to the solution routine of the model. This work presents a general framework for interfacing the dynamic phasor method to the rational models. That would be promising for the electromagnetic transient analysis (under harmonic distortion), in the frequency domain. Therefore, Y-element rational pole-residue models (employing the vector fitting method) are developed. Moreover, the pole-residue model is converted into the state-space representation. Next, the dynamic harmonic approach (in the frequency domain) is employed for harmonic analysis. It is shown that the order of state-space system can become a major concern for frequency-dependent networks analysis. Therefore, to generate a reduced-order model, the balanced realization theory is applied. Moreover, (for the sake of simplicity and efficiency) the trapezoidal integration rule is employed to discretise the state-space equations. For validation of the modelling, it is applied on three test case studies and results of these studies are compared with their time-domain analysis results.