A Multi-Channel 3D-Printed Bioreactor for Evaluation of Growth and Production in the Microalga Dunaliella sp

We explored the capabilities of additive manufacturing using a photo-cured jetted material 3D printer to manufacture a milli-microfluidic device with direct application in microalgae Dunaliella sp growth and intracellular compounds biosynthesis tests. A continuous microbioreactor for microalgae culture was CAD designed and successfully built in 1 hour and 49 minutes using black photopolymer cured by UV and a support material. The microreactor was made up of 2 parts including the bioreactor itself and a microchannel network for culture media fluids and microalgae. Both parts were assembled to form a single unit. Additional optical and auxiliar components were added. An external photodetection system platform helped to read light information coming from the bioreactor, related to microalgae growth and production of Carotenoids. Several tests were carried out to check manufacturing quality, behavior of microalgae inside microreactor, quality of light based data coming from meauring system and comparison of microalgae culture operation using (flasks) and microbioreactor. Growth of microalgae inside the microreactor was unsuccessful and several hypothesis may explain the lack of cell replication, from low CO₂ content to 3D photopolymer incompatibility with cell environment. Further improvements related to gas exchange, specially CO₂, microalgae retention system, high irradiance for light stressing tests and material biocompatibility need to be addressed in future works. From a mechanical point of view it was demonstrated the 3D fabricated microreactor it is possible and that it has promising advantages compared to other microfabrication processes that involve complexity in the design, longer manufacturing time, more expensive and sophisticated manufacturing techniques as well as specialized operators and designers

Global Citizenship Concepts in Curriculum Guidelines of 10 Countries : Comparative Analysis

This paper reports on a study of concepts associated with the new construct of global citizenship education (GCED) in school curricula. We compared the national school curricula of ten countries with markedly different cultures and levels of development across different regions of the world (Africa, Asia, Europe, Latin America, and Southeast Asia) on the presence of concepts associated with GCED. The curricula of both primary and secondary education, in the areas of history and social sciences, and civics and moral education, were compared using a set of categories constructed for this study and derived from UNESCO’s definitions of GCED as well as from the International Association for the Evaluation of Educational Achievement’s (IEA) international assessment studies of civic and citizenship education. Patterns of presence/absence of GCED and related content were identified. The main finding is that only two of the ten countries’ curricula consistently included global citizenship concepts. At the same time, all ten countries, to the extent that the analysis distinguished, included content related to knowledge, values and attitudes that have the world or humanity as referent

Política y políticas educacionales en Chile 1990-2010

Artículo originalEl artículo examina los límites que establecen a las políticas en educación, la fuerza política (poder relativo) y las ideologías de los actores representados en la relación gobierno/oposición en la arena político-institucional, así como la dinámica entre movimento social y respuesta de políticas en este ámbito. En base al marco que establece "la política", se da cuenta de la evolución del conjunto de las políticas públicas en educación en Chile en período 1990-2010 (equivalente a cuatro gobiernos de una misma alianza de centro-izquierda) y su impacto sobre coberturas, calidad y equidad del sistema escolar, por un lado, y de la relación de la sociedad con la temática educativa y sus efectos políticos, por otro. El trabajo concluye atendiendo a los resultados estructurales no buscados por las política

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Resultados de la enseñanza de estrategias de lectura y escritura en la alfabetización temprana de niños con riesgo social

Introducción: La evidencia científica reciente destaca la importancia de la alfabetización temprana como fundamento del aprendizaje lector posterior, especialmente en niños en riesgo social, pero no existen las condiciones adecuadas para alcanzar su desarrollo. El objetivo del estudio fue evaluar los resultados de una intervención focalizada en el aprendizaje temprano de la lectura y la escritura de niños con riesgo social (5 años 3 meses promedio). Material y Métodos: Se evaluaron 339 niños(as) (132 grupo intervención/207 grupo comparación), al inicio y al fin del año escolar. Los profesores del grupo de intervención participaron en un programa de desarrollo profesional de un año que incluyó capacitación y acompañamiento para la aplicación de estrategias de enseñanza de la alfabetización temprana. Resultados: Se observó un resultado positivo en el conocimiento del alfabeto, la escritura emergente y el reconocimiento visual de palabras, no en comprensión oral. Discusión: Se contrastan los resultados con otros programas de intervención en niños con riesgo social, resaltando la importancia de la capacitación y el acompañamiento a los educadores

Collapse of 3D orthogonal woven carbon fibre composites under in-plane tension/compression and out-of-plane bending composite structures

An experimental and numerical investigation was undertaken to characterise the collapse of 3D orthogonal woven carbon fibre composites during the load cases of in-plane tension, inplane compression and out-of-plane bending. Two different fibre architectures, varying only by the density of through-thickness reinforcement, were investigated. Cantilever beam tests were carried out to isolate two distinct collapse mechanisms, i.e. bending governed and shear governed deformation. A qualitative comparison was made with a similar UD-laminate material. 3D woven composites exhibited significantly reduced delamination. An investigation into the efficacy of an embedded element modelling strategy for in-plane tension, in-plane compression and out-of-plane bending load cases was undertaken. The predictions were generally in good agreement with the experimental measurements for the inplane and out-of-plane loading