Abstract:The increasing demands of infrastructures in terms of energy consumption, raw material demand, greenhouse gas emissions, waste management, treatment of components after their lifetime period, and financial costs are nowadays a serious threat for sustainability. Given that the resources are limited, it is difficult to ensure an accurate level of well-being for future generations. For this reason, new perspectives in design, production and consumption are necessary. In this work, the principles of circular economy are applied to concrete branches of engineering. Departing from a design orientated to new uses after life period of infrastructures, a circular economy-aimed engineering makes possible the connection and mutual profit of such different branches like waste management and tunnel lighting. The benefits in environmental and financial terms are a strong argument in favor of a stronger link between engineering and circular economy.

This study analyzes the operation of Biomass System (BIO System) technology for the combustion of pellets from almond and olive trees within the circular economy model. Its aims are the reduction of greenhouse gas emissions as well as waste removal and its energy use by reintroducing that waste into the production process as technological nutrient. In order to do so, combustion efficiency under optimal conditions at nominal power was analyzed. In addition, a TESTO 350-XL analyzer was employed to measure CO and NO x emissions. High combustion efficiency values were obtained, 87.7% and 86.3%, for pellets from olive tree and almond tree, respectively. The results of CO and NO x emission levels were very satisfactory. Under conditions close to nominal power, CO emission levels were 225.3 ppm at 6% O 2 for pellet from almond tree and 351.6 ppm at 6% O 2 for pellet from olive tree. Regarding NO x emissions, the values were 365.8 ppm at 6% O 2 and 333.2 ppm at 6% O 2 for pellets from almond tree and olive tree, respectively. In general, these values were below those legally established by current legislation in European countries. Therefore, BIO System technology is a perfectly feasible option in terms of energy use and circular economy.

Every day, society's concern over pollution caused by plastic waste grows greater. One of the most intensive sectors for the use of plastic is the food industry. Companies in this sector face the challenge of transitioning to a more sustainable and less intensive model of plastic use, respecting the principles established for a circular economy. Accordingly, one of the questions that industries tend to ask is whether sustainability will influence the consumer's purchase decision. To respond to this, the factors that determine a consumer's sustainable purchase decision in relation to the plastic and food industry have been analyzed in this paper. For this, a regression analysis was performed on a sample of Dutch consumers. The results show that the decision of purchase of the consumer of the Food Industry is conditioned by factors such as age, sustainable behavior, knowledge of the Circular economy and the perception of usefulness of plastic.

This study was undertaken to evaluate the role of thyroid hormones in fibrocystic breast disease. The concentrations of thyroid-stimulating hormone (TSH), thyroxine (T4), free T4 and free triiodothyronine (T3) were determined in serum of 50 women with fibrocystic breast disease without macrocysts (cysts of over 3 mm diameter) and in the serum and breast cyst fluid (BCF) of 60 women with fibrocystic breast disease and macrocysts. Possible relationships between thyroid hormones and estradiol, dehydroepiandrosterone sulfate, testosterone, progesterone and 17-hydroxyprogesterone in the BCF also were analyzed. Serum thyroid hormone levels did not differ between the two groups. Free T3 levels were higher in BCF than in serum (p < 0.001), whereas T4, free T4 and TSH concentrations were lower in BCF as compared to serum (p < 0.001). Cysts were divided according to their K+/Na+ ratio because a ratio above 3 represents a predictor of malignant transformation. Free T3 concentrations were higher in BCF than in serum, in both low K+/Na+ cysts and in cysts with a K+/Na+ ratio above 3; those cysts with a high K+/Na+ ratio had the highest free T3 concentration. Free T3 in cysts correlated positively to the K+/Na+ ratio (r = 0.831; p < 0.001). Multiple linear regression analysis demonstrated that the concentration of free T3 in BCF was predicted statistically by the positive regression coefficient for the estradiol concentration. No candidate variable was included in the model to predict concentrations of TSH, free T4 or T4 in BCF. These data suggest an important role of free T3 in the physiology of fibrocystic breast disease.

The sludge generated from water treatment has been classified as a potential environmental pollutant. Because of its chemical composition similar to clay, was proposed to evaluate the effect of its incorporation as a partial substitute for traditional clay materials in the manufacture of aluminosilicate refractory bricks. The raw materials used were characterized by XRD and XRF; the prototypes designed were mixed, extruded, dried and firing at 1200°C, evaluating their linear shrinkage, apparent density, porosity, water absorption and mechanical and pyroscopic resistance (melting cone softening point). The results show the addition of 10% of sludges from industrial water treatment plant, contributedto elevate the softening point the clay that obtaining a refractory brick capable to supporting a temperature up to 1430 °C

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Antecedentes: El sector de la construcción es uno de los sectores económicos en Colombia con mayor crecimiento, generando grandes cantidades de residuos como producto del proceso de construcción, y/o demolición, o en su defecto en la fabricación de los materiales de construcción. Objetivo: facilitar el acceso a información académicocientífica actualizada sobre reciclaje de residuos industriales y su aplicación en la fabricación de materiales de construcción. Así mismo se emplea el término de economía circular, el cual hace referencia a la integración de las actividades de reducción (consumo de energía y residuos), reutilización y recuperación durante la producción, el intercambio y consumo. Conclusión: además de reducir la contaminación generada por los residuos de los sectores productivos, con el aprovechamiento de los subproductos ha sido posible mejorar ciertas propiedades tecnológicas de estos materiales de construcción.Palabras Clave: economía circular, materiales de construcción, nutriente tecnológico, reciclaje, residuos industriales.AbstractBackground: The construction sector is one of the economic sectors with the highest growth in Colombia, generating large amounts of waste as a result of the construction process, and / or demolition, or otherwise in the building material manufacturing. Objective: to facilitate the access to updated academic-scientific information on recycling of industrial waste and its application for the building material manufacturing. Moreover, the concept of circular economy is used, which refers to the integration of the reduction activities (energy consumption and waste),reuse and recycling during the production, exchange and consumption. Conclusion: in addition to the reduction of the pollution generated by waste from the productive sectors, certain technological properties of these building materials have been improved through the use of waste. Keywords: circular economy, building materials, technological nutrient, recycling, industrial waste.

Water pollution is a worldwide problem. Water consumption increases at a faster rate than population and this leads to a higher pollution rate. Sustainable Development Goals (SDG) include proposals aimed at ensuring the availability of clean water and its sustainable management (Goal 6), as well as the conservation and sustainable use of oceans and seas. The current trend consists in trying to reconcile economic growth with sustainability, avoiding the negative externalities for the environment generated by human activity. More specifically, the objective of this article is to present the evolution of the research regarding the removal of polluting pharmaceuticals that are discharged into wastewater. To do that, a bibliometric analysis of 2938 articles comprising the period 1979–2020 has been carried out. This analysis includes productivity indicators in the scientific field: journals, authors, research institutions and countries. In addition, keyword analysis allows the identification of four main axes of the research regarding the removal of pharmaceutical residues found in wastewater. The first group of articles is aimed at identifying the pharmaceuticals present in polluting effluents. The second and third groups of articles focus on presenting the procedures that enable the treatment of emerging contaminants, either from a biological point of view (second group) or a physicochemical point of view (third group). The fourth group refers to water quality and its possibilities to be reused. Finally, there is a growing trend of worldwide scientific publications, which justifies the importance of polluting residues management, especially those of pharmaceutical origin, in order to achieve a more sustainable society.