The need to satisfy the increasing demand for building materials and the challenge of reusing plastic to help improve the critical environmental crisis has led to the recycling of plastic waste, which is further exploited and transformed into new and creative materials for the construction industry. This study looked into the use of low-density recycled polyethylene (LDPE) to produce non-conventional plastic sand cobbles. LDPE waste was melted in order to obtain enough fluid consistency which was then mixed with sand in a 25/75 plastic-sand ratio respectively, such a mixture helped producing cobbles of 10 cm × 20 cm × 4 cm. Water absorption, weight, and density measurements were performed on both commercial and non-conventional plastic sand cobbles. Moreover, compression, bending, and wear resistance were also conducted as part of their mechanical characterization. Plastic sand cobbles showed lower water absorption and density values than commercial cobbles. The mechanical properties evaluated showed that plastic sand cobbles have a higher modulus of rupture and wear resistance than commercial cobbles. In addition, plastic sand cobbles meet the Colombian Technical Standard in lightweight traffic for pedestrians and vehicle, officially known as Norma Técnica Colombiana (NTC), with 25.5 MPa, 16.3 MPa, and 12 mm compression resistance, modulus of rupture and footprint length in wear resistance respectively. Finally, a market study was conducted to establish a factory to produce this type of cobbles in Ibague, Colombia. Not only the study showed positive financial indicators, which means that it is feasible running a factory to manufacture plastic sand cobbles in the city of Ibague, but it also concluded that nonconventional plastic sand cobbles could be explored to provide a comprehensive alternative to LDPE waste.

In Colombia, most commercial drying processes are frequently performed through the burning of wood and fossil fuels with high costs and environmental damage. Nevertheless, solar drying is a technique that could also be used to reduce many of the problems present in traditional drying techniques. Finding low-cost technology to install a solar dryer in a vulnerable community of women is an appropriate alternative; the transfer of knowledge on this technique could lead to greater empowerment of women and prevent gender inequality. This study evaluated the color and water activity of the mango (Mangifera indica L.) after a drying process in a greenhouse dryer. Furthermore, this study showed the relevance of implementing this technique in a community of women affected by the military conflict in Colombia. Results showed that a solar dryer achieved drying times of around 23–26 h, reaching water activity values below the 0.5 threshold which, according to international standards, has been considered as a food safety value. In addition, the color of the dry mango is slightly affected through this drying technique, providing a more acceptable consumer product. The application of the solar dryer has proven to be an easy-to-use and environmentally friendly method. On the other hand, it is also an opportunity to improve, with a low-cost investment, the living conditions of vulnerable communities.

Los países en desarrollo y aquellos con tradición agrícola tienen entre sus prioridades gubernamentales el diseño e implementación de planes de mejora para aumentar la productividad en este sector. La priorización de esos planes tiende a basarse en la evaluación de indicadores de producción, dejando de lado aspectos logísticos clave como transporte, manipulación, embalaje, entre otros. Por esta razón, este trabajo propone una metodología multicriterio, basada en el método de expertos y el método de planificación del desarrollo tecnológico en cadenas agroindustriales propuesto por ISNAR, que estiman el índice de potencial logístico (LPi) y el índice de nivel de competitividad (LCi). El análisis conjunto de ambos indicadores permitió priorizar los productos en una matriz denominada matriz de priorización. La metodología fue validada en un caso de estudio a través de la priorización de productos hortícolas y frutales en cinco zonas del Tolima - Colombia para asignar recursos con el fin de implementar estrategias logísticas.

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