El Árbol de la Ciencia: actividad didáctica en Educación Infantil con códigos QR para el aprendizaje del medio natural a partir de los intereses del alumnado

Congreso Internacional Virtual USATIC 2019, Ubicuo y Social: Aprendizaje con TIC (2019, Zaragoza)En la Didáctica del Medio Natural se han hecho habituales los procesos de enseñanza-aprendizaje que emplean dispositivos móviles para facilitar el conocimiento del entorno natural, tanto como apoyo a la enseñanza presencial como en aprendizajes totalmente móviles (m-learning) y ubicuos (u-learning) (Torralba-Burrial & Herrero, 2016). En este sentido, los códigos QR facilitan la relación con información disponible ubicuamente en Internet mediante un enlace codificado interpretable por dispositivos móviles. Constituyen así el nivel más sencillo de realidad aumentada (revisiones Fombona, Pascual & Madeira, 2012; Prendes, 2015). Se describe la experiencia llevada a cabo con alumnado de 3 años de Educación Infantil. Se diseñó en el rincón de ciencias del aula un mural con un árbol y hojas sueltas, simbolizando el Árbol de la Ciencia. Sobre él, el alumnado podía colocar más hojas con preguntas o ilustraciones sobre sus intereses directos en el conocimiento del entorno natural. En los días siguientes, la maestra respondía estas preguntas con un código QR para cada una de ellas, que ponía en su respectiva hoja a los pies del árbol. El alumnado con una tablet, capturaba el código QR, observando y comentando la respuesta. La experiencia resultó altamente positiva en cuanto a la motivación del alumnado, tanto a la hora de preparar las preguntas como al esperar el momento que el árbol mostrara la respuesta en la tableta

Comparative study of different methodologies to determine the exopolysaccharide produced by kefir grains in milk and whey

Quantitative isolation of lactic acid bacteria exopolysaccharides (EPS) from dairy products is an important step to determine small amounts of EPS (between 25 and 890 mg·L-1) in a medium that contains 30 to 50 g·L-1 of lactose. Kefir grains CIDCA AGK1 are able to produce an exopolysaccharide commonly known as kefiran when grown in milk and deproteinised whey. Different methodologies were compared for kefiran isolation from milk and whey fermented for 96 h at 20 °C with 100 g·L-1 of kefir grains. Methods that included one or two steps of ethanol precipitation, one step of ethanol precipitation followed by dialysis, direct dialysis with membranes of different cut-off (1 000, 6 000, 12 000), and a TCA precipitation step were evaluated. The effect of a heat treatment of the milk on EPS recovery was also studied. The highest recovery of EPS was obtained when samples were heated as a first step of isolation. Methods that contained two steps of ethanol precipitation, one step of ethanol precipitation followed by dialysis or direct dialysis (molecular weight cut-off lower than 6 000 to 8 000) gave the highest values of polysaccharide concentration (218 mg·L-1 of fermented milk and 247 mg·L-1 of fermented whey). One step of ethanol precipitation did not completely eliminate residual lactose. EPS was partially lost when dialysis was carried out with membranes of cut-off of 12 000. About 50% of EPS was lost when the method included a step of TCA precipitation. We conclude that polysaccharide quantified in milk and deproteinised whey fermented with kefir grains strongly depends on the isolation methodology used.Fil: Rimada, Pablo Sebastián. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Abraham, Analia Graciela. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Multiscale approaches to high efficiency photovoltaics

While renewable energies are achieving parity around the globe, efforts to reach higher solar cell efficiencies becomes ever more difficult as they approach the limiting efficiency. The so-called third generation concepts attempt to break this limit through a combination of novel physical processes and new materials and concepts in organic and inorganic systems. Some examples of semi-empirical modelling in the field are reviewed, in particular for multispectral solar cells on silicon (french ANR project MULTISOLSI). Their achievements are outlined, and the limits of these approaches shown. This introduces the main topic of this contribution, which is the use of multiscale experimental and theoretical techniques to go beyond the semi-empirical understanding of these systems. This approach has already led to great advances at modelling which have led to modelling software which is widely known. Yet a survey of the topic reveals a fragmentation of efforts across disciplines, firstly, such as organic and inorganic fields, but also between the high efficiency concepts such as hot carrier cells and intermediate band concepts. We show how this obstacle to the resolution of practical research obstacles may be lifted by inter-disciplinary cooperation across length scales, and across experimental and theoretical fields, and finally across materials systems. We present a European COST Action MultiscaleSolar kicking off in early 2015 which brings together experimental and theoretical partners in order to develop multiscale research in organic and inorganic materials. The goal of this defragmentation and interdisciplinary collaboration is to develop understanding across length scales which will enable the full potential of third generation concepts to be evaluated in practise, for societal and industrial applications.Comment: Draft paper accompanying a plenary presentation to the World Renewable Energy Conference WREC 2015, June 2015, Bucharest. In press (IOP

Solvent and substituent effects on the thermolysis of antimalarial fluorophenyl substituted 1,2.4-trioxanes

The kinetics and mechanism of the thermal decomposition reaction of cis-6-(4-fluoropheny1)-5,6-[2-(4-fluorophenyl)-propylidene]-3, 3-tetramethylene-1,2,4-trioxacyclo-hexane (I) were investigated separately in n-hexane and in methanol solutions over the temperature and concentration ranges of 393.2-443.2 K and 2.7-54 × 10-5 M, respectively. The values of the activation parameters for both reactions were compared with the corresponding ones for the thermolysis of cis-6-(4-fluorophenyl-5,6-[2-(4- fluorophenyl)-3-hydroxypropylidene]-3,3-tetramethylene-1,2,4-trioxacyclohexane (II), investigated in the same solvents and temperature range. Substituent and solvent effects on the initial homolytic rupture of the O-O peroxydic bonds of those molecules were evaluated.Facultad de Ciencias Exacta

Solvent and substituent effects on the thermolysis of antimalarial fluorophenyl substituted 1,2.4-trioxanes

The kinetics and mechanism of the thermal decomposition reaction of cis-6-(4-fluoropheny1)-5,6-[2-(4-fluorophenyl)-propylidene]-3, 3-tetramethylene-1,2,4-trioxacyclo-hexane (I) were investigated separately in n-hexane and in methanol solutions over the temperature and concentration ranges of 393.2-443.2 K and 2.7-54 × 10-5 M, respectively. The values of the activation parameters for both reactions were compared with the corresponding ones for the thermolysis of cis-6-(4-fluorophenyl-5,6-[2-(4- fluorophenyl)-3-hydroxypropylidene]-3,3-tetramethylene-1,2,4-trioxacyclohexane (II), investigated in the same solvents and temperature range. Substituent and solvent effects on the initial homolytic rupture of the O-O peroxydic bonds of those molecules were evaluated.Facultad de Ciencias Exacta

Projecte d'urbanització smart a La Garriga

L’objectiu del present projecte és dissenyar, calcular, definir constructivament i avaluar econòmicament les obres necessàries, bàsiques i complementàries per a desenvolupar una urbanització smart a la població de La Garriga. El concepte smart implica l’aplicació d’avanços tecnològics per millorar la qualitat de vida de les persones que viuen en la urbanització i facilitar el treball de gestió i manteniment dels serveis instal·lats en aquest

Solvent and substituent effects on the thermolysis of antimalarial fluorophenyl substituted 1,2.4-trioxanes

The kinetics and mechanism of the thermal decomposition reaction of cis-6-(4-fluoropheny1)-5,6-[2-(4-fluorophenyl)-propylidene]-3, 3-tetramethylene-1,2,4-trioxacyclo-hexane (I) were investigated separately in n-hexane and in methanol solutions over the temperature and concentration ranges of 393.2-443.2 K and 2.7-54 × 10-5 M, respectively. The values of the activation parameters for both reactions were compared with the corresponding ones for the thermolysis of cis-6-(4-fluorophenyl-5,6-[2-(4- fluorophenyl)-3-hydroxypropylidene]-3,3-tetramethylene-1,2,4-trioxacyclohexane (II), investigated in the same solvents and temperature range. Substituent and solvent effects on the initial homolytic rupture of the O-O peroxydic bonds of those molecules were evaluated.Facultad de Ciencias Exacta

Towards 50% Efficiency in Solar Cells

International audienc