Dels materials clàssics als alternatius en la preparació de substrats. Motivacions de la substitució, tendències, disponibilitat i característiques

En el context hortícola, el terme substrat s’aplica a qualsevol material sòlid, diferent del sòl insitu, natural o artificial, pur o en barreja, que col·locat en un contenidor i sotmès a un programa específic de gestió (principalment reg i fertilització) permet l’establiment de l’aparell radicular amb un grau d’aeració satisfactori, possibilita una adequada nutrició hídrica i mineral i actua com a suport de la planta.Postprint (published version

Entorno virtual de aprendizaje compartido en Educación Superior

Cada vez son m&aacute;s demandadas las plataformas virtuales apoyadas en el concepto web 2.0 y en las Redes Personales de Aprendizaje (PLN) al garantizar la conversaci&oacute;n entre agentes educativos y la colaboraci&oacute;n orientada a la producci&oacute;n conjunta de conocimiento. Desde este punto de vista, surgieron los Entornos Virtuales de Aprendizaje (VLE) d&oacute;nde se configuran, integran y combinan nuevas aplicaciones adaptadas a las necesidades de los usuarios. El prop&oacute;sito final de esta experiencia es la creaci&oacute;n de un entorno virtual compartido para lograr que el aprendizaje no se vincule exclusivamente a una actividad memor&iacute;stica y que a trav&eacute;s del uso combinado de la plataforma virtual, herramientas de la web 2.0 y la red social los estudiantes puedan crear su propio espacio de trabajo en el que quede reflejado la b&uacute;squeda y transformaci&oacute;n de la informaci&oacute;n, creaci&oacute;n de recursos para el aprendizaje y tareas de colaboraci&oacute;n. Nuestro entorno virtual de aprendizaje compartido ha sido puesto a prueba, implementado y evaluado durante el segundo cuatrimestre, en el marco de la asignatura Did&aacute;ctica General en la Facultad de Ciencias de la Educaci&oacute;n de la Universidad de Sevilla (Espa&ntilde;a) durante el curso acad&eacute;mico 2009-2010. Una encuesta efectuada revela hechos interesantes sobre el &eacute;xito de este entorno virtual compartido en relaci&oacute;n con la motivaci&oacute;n y los resultados de aprendizaje de los estudiantes.&nbsp;&nbsp;ABSTRACTShared virtual learning environments in higher education.&nbsp;There is an increasing demand for virtual platforms based on the concept of Web 2.0 and on Personal Learning Networks (PLN) as these guarantee conversations between educational agents and cooperation aimed at the joint knowledge production. From this point of view, Virtual Learning Environments (VLE) have emerged in which new applications adapted to users&rsquo; needs are configured, integrated and combined. The ultimate purpose of this experience is the creation of a shared virtual environment to ensure that learning is not linked exclusively to rote activity. Through the combined use of the virtual platform, Web 2.0 tools and social networking, students can create their own workspace in which the search and processing of information, as well as the creation of learning resources and collaboration tasks are reflected. Our shared virtual learning environment has been tested, implemented and evaluated in the second semester, as part of the General Teaching Methodology course in the Faculty of Education at the University of Seville (Spain) during the 2009 &ndash; 2010 academic year. A survey reveals interesting facts about the success of the shared virtual environment in relation to the motivation and learning outcomes of students.&nbsp;</p

Development of organic fertilizers from food market waste and urban gardening by composting in Ecuador

Currently, the management of urban waste streams in developing countries is not optimized yet, and in many cases these wastes are disposed untreated in open dumps. This fact causes serious environmental and health problems due to the presence of contaminants and pathogens. Frequently, the use of specific low-cost strategies reduces the total amount of wastes. These strategies are mainly associated to the identification, separate collection and composting of specific organic waste streams, such as vegetable and fruit refuses from food markets and urban gardening activities. Concretely, in the Chimborazo Region (Ecuador), more than 80% of municipal solid waste is dumped into environment due to the lack of an efficient waste management strategy. Therefore, the aim of this study was to develop a demonstration project at field scale in this region to evaluate the feasibility of implanting the composting technology not only for the management of the organic waste fluxes from food market and gardening activities to be scaled-up in other developing regions, but also to obtain an end-product with a commercial value as organic fertilizer. Three co-composting mixtures were prepared using market wastes mixed with pruning of trees and ornamental palms as bulking agents. Two piles were created using different proportions of market waste and prunings of trees and ornamental palms: pile 1 (50:33:17) with a C/N ratio 25; pile 2: (60:30:10) with C/N ratio 24 and pile 3 (75:0:25) with C/N ratio 33), prepared with market waste and prunings of ornamental palm. Throughout the process, the temperature of the mixtures was monitored and organic matter evolution was determined using thermogravimetric and chemical techniques. Additionally, physico-chemical, chemical and agronomic parameters were determined to evaluate compost quality. The results obtained indicated that all the piles showed a suitable development of the composting process, with a significant organic matter decomposition, reached in a shorter period of time in pile 3. At the end of the process, all the composts showed absence of phytotoxicity and suitable agronomic properties for their use as organic fertilizers. This reflects the viability of the proposed alternative to be scaled-up in developing areas, not only to manage and recycle urban waste fluxes, but also to obtain organic fertilizers, including added value in economic terms related to nutrient contents.Peer ReviewedPostprint (published version

Is Cycling Safe? Does It Look like It? Insights from Helsinki and Barcelona

[EN] Cycling constitutes a clean, healthy, and low-cost mode of transport. Therefore, the promotion of cycling is currently one of the main goals of administrations around the word. Former studies have shown that safety perception plays a fundamental role in the acceptance of bikes as a habitual mode of transport. In this context, this research aims to determine which variables and actions can give rise to this feeling of safety and, therefore, collaborate in the modal shift towards a more sustainable mobility. For this purpose, different strategies have been developed in two different contexts, Helsinki and Barcelona, using two different methodologies, namely expert interviews and analysis of survey data. Particularly, the methodology of analysis used includes descriptive statistics and path analysis. Results point out that safety perception highly depends on trip purpose, as significant differences are observed for daily users compared to those who cycle for sport reasons. Demographic characteristics (age, gender, etc.) and use patterns are also associated with different perceptions of safety and different behaviors. However, for any cyclist, the quality of the available infrastructure significantly influences his/her safety perception. Thus, the provision of good quality and well-structured cycling infrastructure is the most important initiative to promote cycling.Martínez-Díaz, M.; Arroyo-López, MR. (2023). Is Cycling Safe? Does It Look like It? Insights from Helsinki and Barcelona. Sustainability. 15(2):1-25. https://doi.org/10.3390/su1502090512515

Approaching compost stability from Klason lignin modified method: Chemical stability degree for OM and N quality assessment

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Estudio longitudinal sobre redes sociales como método didáctico

This article gathers the perceptions of students on social networks, as a didactic method, with the aim of searching and designing didactic strategies to adapt the contents and methodology to the new technological context. The parti- cipants were university students of Early Childhood and Pri- mary Education in 2013-2014 and 2016-2017. A longitudinal study was conducted with a descriptive, non-experimental methodology and the semi-structured questionnaire used was validated through factorial and cluster analyses. The students from both degrees showed a polarization and dis- persion of opinions about social networks, which could be related to a more critical attitude toward their advantages and disadvantages.Este artículo recoge las percepciones de los estudiantes sobre las redes sociales como método didáctico, con el propósito de investigar y diseñar estrategias didácticas para adaptar los contenidos y la metodología al nuevo contexto tecnológico. Los participantes fueron estudiantes universitarios del pro- grama de Educación primaria y de la temprana infancia de los periodos 2013-2014 y 2016-2017. Se hizo un estudio lon- gitudinal con una metodología no-experimental, descriptiva y se validó un cuestionario semi-estructurado a través de aná- lisis factorial y de grupos. Los estudiantes de ambos periodos mostraron una polarización y dispersión de opiniones sobre las redes sociales, lo que podría estar relacionado con una actitud más crítica con respecto a sus ventajas y desventajas

Proceso para la validación de prácticas empresariales internacionales, oficina de relaciones internacionales Universidad Tecnológica de Pereira

El presente documento tiene como finalidad mostrar cuales son las necesidades que se identificaron al interior de la comunidad Universitaria con relación a la validación de practicas empresariales como trabajo de grado y describir brevemente cual es el proceso que debe implementarse para ello.This paper aims to describe the needs that were identified within the University community regarding the validation of an Assistantship as a thesis and describe briefly what is the process that must be submitted for it

Guia de l’usuari: el compostatge casolà

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