Un enfoque de trabajo en el aula : la actividad científica escolar

La investigación que se presenta tiene como objetivo analizar la actividad científica escolar que se desarrolla con un grupo de estudiantes de 14 y 15 años mientras trabajaban el tema de la nutrición en un Instituto de Educación Secundaria de Barcelona (España). La profesora utiliza diversas modalidades educativas, realiza experimentos, explica, presenta un vídeo a sus estudiantes. A través de esas actividades, obtiene textos, resúmenes e informes de prácticas; estos materiales constituyen los datos para nuestra investigación. El análisis de las producciones de los estudiantes nos sirve para interpretar cómo se construye la actividad científica escolar a partir de sus cuatro elementos fundamentales: la experiencia, los modelos teóricos, las metas y los lenguajes. En esta comunicación se presentan resultados empíricos en relación con el análisis de una intervención didáctica centrada en la habilidad cognitivolingüística del resumen

Seasonal Variation of Essential Oil Yield and Composition of Sage (Salvia officinalis L.) Grown in Castilla - La Mancha (Central Spain)

Links between phenology, yield and composition of the essential oil of common sage, Salvia officinalis L., grown in Guadalajara (Central Spain) were determined in the different phases of the biological cycle during one year. Data showed an average yield about 1.0%. The analysis of the oil components was carried out by GC-FID and GC/MS. The main oil constituent was alpha thujone (40.1 - 46.5%). Other identified compounds are beta pinene (2.6 - 4.5%), cineole (3.5 - 8.7%), beta thujone (4.1 - 5.6%), camphor (4.1 - 8.0%), borneol (1.3 - 3.7%), alpha humulene (3.8 - 7.3%), viridiflorol (3.4-12.6%) and manool (0.1-4.5%). The highest yield of oil was obtained in the period of full flowering and the highest concentration of alpha thujone in the period of initial flowering

Dynamics of entanglement in quantum computers with imperfections

The dynamics of the pairwise entanglement in a qubit lattice in the presence of static imperfections exhibits different regimes. We show that there is a transition from a perturbative region, where the entanglement is stable against imperfections, to the ergodic regime, in which a pair of qubits becomes entangled with the rest of the lattice and the pairwise entanglement drops to zero. The transition is almost independent of the size of the quantum computer. We consider both the case of an initial maximally entangled and separable state. In this last case there is a broad crossover region in which the computer imperfections can be used to create a significant amount of pairwise entanglement.Comment: 4 pages, 4 figure

An Effective Field Theory Look at Deep Inelastic Scattering

This talk discusses the effective field theory view of deep inelastic scattering. In such an approach, the standard factorization formula of a hard coefficient multiplied by a parton distribution function arises from matching of QCD onto an effective field theory. The DGLAP equations can then be viewed as the standard renormalization group equations that determines the cut-off dependence of the non-local operator whose forward matrix element is the parton distribution function. As an example, the non-singlet quark splitting functions is derived directly from the renormalization properties of the non-local operator itself. This approach, although discussed in the literature, does not appear to be well known to the larger high energy community. In this talk we give a pedagogical introduction to this subject.Comment: 11 pages, 1 figure, To appear in Modern Physics Letters

Recent developments in nanostructured materials for high-performance thermoelectrics

This highlight discusses recent trends in the search for new high-efficiency thermoelectric materials. Thermoelectric materials offer considerable attractions in the pursuit of a more efficient use of existing energy resources, as they may be used to construct power-generation devices that allow useful electrical power to be extracted from otherwise waste heat. Here, we focus on the significant enhancements in thermoelectric performance that have been achieved through nanostructuring. The principal factor behind the improved performance appears to be increased phonon scattering at interfaces. This results in a substantial reduction in the lattice contribution to thermal conductivity, a low value of which is a key requirement for improved thermoelectric performance

El movimiento MAKER desde la perspectiva digital: los docentes y la construcción de recursos educativos

La presente propuesta, se centra en la posibilidad de que el docente asuma el reto de construir sus recursos educativos, usarlos en sus clases y compartirlos con otros docentes, para lo cual requiere ante todo su creatividad, entusiasmo y conocimientos básicos en el uso de software de autor. Esto también aplica para los estudiantes, ya que el manejo de este tipo de herramientas informáticas les permite aprender colaborativamente construyendo recursos para compartir con sus compañeros, aprender juntos y hacer procesos de coevaluación permanentes

Ball milling as an effective route for the preparation of doped bornite: synthesis, stability and thermoelectric properties

Bornite, Cu5FeS4, is a naturally-occuring mineral with an ultralow thermal conductivity and potential for thermoelectric power generation. We describe here a new, easy and scalable route to synthesise bornite, together with the thermoelectric behaviour of manganese-substituted derivatives, Cu5Fe1-xMnxS4 (0 ≤ x ≤ 0.10). The electrical and thermal transport properties of Cu5Fe1-xMnxS4 (0 ≤ x ≤ 0.10), which are p-type semiconductors, were measured from room temperature to 573 K. The stability of bornite was investigated by thermogravimetric analysis under inert and oxidising atmospheres. Repeated measurements of the electrical transport properties confirm that bornite is stable up to 580 K under an inert atmosphere, while heating to 890 K results in rapid degradation. Ball milling leads to a substantial improvement in the thermoelectric figure of merit of unsusbtituted bornite (ZT = 0.55 at 543 K), when compared to bornite prepared by conventional high-temperature synthesis (ZT < 0.3 at 543 K). Manganese-substituted samples have a ZT comparable to that of unsubstituted bornite

Working Environment in Nursing: Needs Improvement?

Background: Knowing the quality of life of professionals is important because it is related to job performance, better results, and greater productivity, which results in better patient care. Objective: To know the Professional Quality of Life perceived by the nurses at the Geriatric Hospital of Toledo (Spain). Method: A descriptive cross-section study was employed to measure the Professional Quality of Life of all healthcare nurses (69 in total) at the Geriatric Hospital of Toledo. The questionnaire used as a measuring instrument was the Professional Quality of Life - 35. The data obtained was analyzed by means of: descriptive statistics, single-factor ANOVA variance analysis, T Student tests, and simple and multiple regression analysis. The study was approved by both the research commission and the ethics commission at the Hospital Complex of Toledo. Participation in the study on behalf of the nursing staff was voluntary. Results: In total, 45 responses were obtained (65.2%). The overall mean score measured the perceived Professional Quality of Life to be low. In relation to the three dimensions evaluated in the study, the highest average found was in “intrinsic motivation,” followed by “workload”, and then “management support.” In the multivariate analysis, “management support” was shown as the most influential factor in the Professional Quality of Life with a 23% influence (P<0.001), followed by workload with 9% (P = 0.01). Conclusions: The professionals at the participating center perceive their workplace as having an elevated degree of responsibility, a large quantity of work, a high occurrence of rushes and fatigue, and all this with little support on behalf of management. Promotions are scarce or the policies for receiving a promotion are inadequate. The perception of Professional Quality of Life in nursing is low. The obtained results indicate a need for an organizing cultural change based on participation, motivation, and increased management support