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BackgroundAlcohol abuse is a risk factor for bone damage and fracture‐related complications. Through precise β‐catenin signaling, canonical Wnt signaling plays a key role in fracture repair by promoting the differentiation of new bone and cartilage cells. In this study, we examined the effects of alcohol on the Wnt pathway in injured bone using a murine model of alcohol‐induced impaired fracture healing.MethodsMale C57Bl/6 or T cell factor (TCF)‐transgenic mice were administered 3 daily intraperitoneal doses of alcohol or saline. One hour following the final injection, mice were subjected to a stabilized, mid‐shaft tibial fracture. Injured and contralateral tibias were harvested at 6, 9, or 14 days post‐fracture for the analysis of biomechanical strength, callus tissue composition, and Wnt/β‐catenin signaling.ResultsAcute alcohol treatment was associated with a significant decrease in fracture callus volume, diameter, and biomechanical strength at day 14 post‐fracture. Histology revealed an alcohol‐related reduction in cartilage and bone formation at the fracture site, and that alcohol inhibited normal cartilage maturation. Acute alcohol exposure caused a significant 2.3‐fold increase in total β‐catenin protein at day 6 and a significant decrease of 53 and 56% at days 9 and 14, respectively. lacZ staining in β‐galactosidase‐expressing TCF‐transgenic mice revealed spatial and quantitative differences in Wnt‐specific transcriptional activation at day 6 in the alcohol group. Days 9 and 14 post‐fracture showed that acute alcohol exposure decreased Wnt transcriptional activation, which correlates with the modulation of total β‐catenin protein levels observed at these time points.ConclusionsAcute alcohol exposure resulted in significant impairment of fracture callus tissue formation, perturbation of the key Wnt pathway protein β‐catenin, and disruption of normal Wnt‐mediated transcription. These data suggest that the canonical Wnt pathway is a target for alcohol in bone and may partially explain why impaired fracture healing is observed in alcohol‐abusing individuals.

The paper presents an experimental study on the formation process of burden surface texture on the blast furnace throat and its influence on the radial distribution of gas flow. The study was performed with the application of blast furnaces equipped with a bell-type charging device using radio-isotope means for the control of burden surface texture (profile) and burden surface level, i.e., gamma locators for burden surface texture. The study was carried out under the conditions of an operating blast furnace in an iron and steel plant using a unique GEOTAPS system for automated control of geometric and temperature parameters of burden material surface on the blast furnace throat. The influence of the surface texture on the gas flow distribution was also investigated. The possibility of a self-stabilization effect for burden surface texture and gas flow in an operating blast furnace under suitable conditions was experimentally proven. As a result of the experimental study performed, four ways of energy-saving technology implementation were determined for the control of blast furnace melting based on the data on the burden surface texture and previously unknown regularities of surface layer formation of burden material on the throat of an operating blast furnace with a bell-type charging device. The main idea of the paper is the development of automated control for the radial distribution of burden material and gas flow using actual or predicted surface texture parameters as important intermediate factors that both describe the process and have a significant simultaneous influence on it.

Construction involves the use of significant quantities of raw materials and entails high-energy consumption. For the sake of choosing the most appropriate solution that considers environmental and sustainable concepts, tools such as the integrated value model for sustainable assessment (Modelo Integrado de Valor para una Evaluación Sostenible, MIVES) used in Spain, plays a key role in obtaining the best solution. MIVES is a multi-criteria decision-making method based on the value function concept and the seminars delivered by experts. Such tools, in order to show how they may work, require application to case studies. In this paper, two concrete slabs manufactured with differing reinforcements during the construction of the La Canda Tunnels are compared by means of MIVES. The two concrete slabs were reinforced with a conventional steel-mesh and with polyolefin fibres. This research was focussed on the main aspects affecting the construction. That is to say, the environmental, economic, and social factors were assessed by the method, being of special impact the issues related with maintenance of the structure. The results showed that from the point of view of sustainability, the use of polyolefin fibres provided a significant advantage, mainly due to the lower maintenance required.

The ethanolic fermentation of liquid fractions (hydrolysates) issued from dilute acid pre-treatment of olive tree biomass by Pichia stipitis is reported for the first time. On the one side, P. stipitis has been reported as the most promising naturally occurring C5 fermenting microorganism; on the other side, olive tree biomass is a renewable, low cost, and lacking of alternatives agricultural residue especially abundant in Mediterranean countries. The study was performed in two steps. First, the fermentation performance of P. stipitis was evaluated on a fermentation medium also containing the main inhibitors found in these hydrolysates (acetic acid, formic acid, and furfural), as well as glucose and xylose as carbon sources. The effect of inhibitors, individually or in a mixture, on kinetic and yield parameters was calculated. In a second step, hydrolysates obtained from 1% (w/w) sulfuric acid pre-treatment of olive tree biomass at 190ºC for 10 min were used as a real fermentation medium with the same microorganism. Due to inhibition, effective fermentation required dilution of the hydrolysate and either overliming or activated charcoal treatment. Results show that ethanol yields obtained from hydrolysates, ranging from 0.35 to 0.42 g/g, are similar to those from synthetic medium, although the process proceeds at lower rates. Inhibiting compounds affect the fermentation performance in a synergistic way. Furfural is rapidly assimilated by the yeast; acetic acid and formic acid concentrations decrease slowly during the process. Activated charcoal or overliming detoxification improve the fermentability of diluted hydrolysates.

Sustainable electricity generation is one of the major current challenges for our society. In this context, the evolution of nanomaterials and nanotechnologies has enabled the fabrication of microscopic devices to produce clean energy from a great variety of renewable sources. To expand the possibilities of energy generation, we have designed and fabricated bioinorganic generators capable to produce electricity by conversion of chemical energy from renewable fuel sources. Unlike traditional generators, the systems described herein produce mechanical energy through enzyme-driven gas production which generates vibration and pressure that are thus converted into electricity by the action of a piezoelectric component properly integrated into the device. Our generators are able to produce an electric ernergy from different renewable sources like glucose, ethanol, and amino acids, attaining energy outputs around 250 nJ cm–2 and reaching maximum open-circuit voltages of up to 1 V. In addition, the produced energy can be easily regulated by adjusting both enzyme and fuel concentration which can tune the electrical output according to the application. The systems described herein propose a new concept for self-sufficient energy harvesting that bridges biocatalysis and piezoelectricity, where the energy production is based on the piezoelectric effect triggered by enzymatic action rather than on the enzyme-driven electron transfer that governs biofuel cells. Although the electric output is too low yet to be considered an alternative for energy production, this technology opens the door to power small devices. We envision the utilization of this technology in such remote locations where mechanical energy is lacking but there are chemical energy reservoirs. We would like to acknowledge Marie-Curie Actions (NANOBIENER project), IKERBASQUE foundation for funding F.L.-G., and the support of COST Action CM1303 Systems Biocatalysis. We also acknowledge HERGAR foundation for the funding. Peer reviewed

Este trabajo se centra en el modelado mediante TRNSYS de una bomba de calor geotérmica agua-agua que utiliza CO2 como refrigerante para producir agua caliente sanitaria (ACS), para posteriormente hacer un estudio comparativo con una instalación solar. Dicha instalación se encuentra disponible en el laboratorio de Calor y Frío del ELDI. Los objetivos principales del trabajo son: - Estudiar y entender el funcionamiento de la bomba de calor y de todos sus componentes. - Conocer las ventajas que presente el CO2 como refrigerante. - Búsqueda de información acerca de los sistemas de captación de energía geotérmica. - Modelar los componentes que constituyen una bomba de calor geotérmica. - Programar los modelos seleccionados mediante el compilador FORTRAN. - Simulación de la bomba de calor en TRNSYS a partir de los componentes programados que la forman. - Realizar un estudio comparativo con un sistema solar convencional a base de colectores solares. ; Escuela Técnica Superior de Ingeniería Industrial ; Universidad Politécnica de Cartagena

The objective of this work is to valorise the discharges (rejections) of the Boukhedra iron ore mine (east of Algeria) as raw materials for the elaboration of the cement raw. The study concerns the development of different types of low impact environmental belite cements whose raw are exclusively mine rejections. The use of a low CaO / SiO2 ratio and the combination of quick cooling of clinker with adequate NaF and LiF mineralization in association with CaSO4, has led to the production of belite cement with high hydraulic reactivity comparable to that of ordinary Portland cements. The used mineralization plays also a positive role in improving performance in terms of firing of the raw, by lowering the clinker process temperatures of these cements, thus, enabling an additional gain in terms of environmental impact and energy consumption. This mineralization and the low LSF of these cements allows obtaining them at low burning temperatures 1150 °C and 1100 °C for the cement with 2%LiF. This is 350 °C lower to ordinary Portland cement. The addition of CaSO4, NaF and LiF to the clinkers makes the improvement of its clinkering possible. The effect of LiF seems to be the most significant followed by NaF and finally, CaSO4

The energy considered as waste heat in industrial furnaces owing to inefficiencies represents a substantial opportunity for recovery by means of thermal energy storage (TES) implementation. Although conventional systems based on sensible heat are used extensively, these systems involve technical limitations. Latent heat storage based on phase change materials (PCMs) results in a promising alternative for storing and recovering waste heat. Within this scope, the proposed PCM-TES allows for demonstrating its implementation feasibility in energy-intensive industries at high temperature range. The stored energy is meant to preheat the air temperature entering the furnace by using a PCM whose melting point is 885 °C. In this sense, a heat transfer model simulation is established to determine an appropriate design based on mass and energy conservation equations. The thermal performance is analysed for the melting and solidification processes, the phase transition and its influence on heat transference. Moreover, the temperature profile is illustrated for the PCM and combustion air stream. The obtained results prove the achievability of very high temperature levels (from 700 to 865 °C) in the combustion air preheating in a ceramic furnace; so corroborating an energy and environmental efficiency enhancement, compared to the initial condition presenting an air outlet at 650 °C.