Enhancing Expectations of Cooperative Learning Use through Initial Teacher Training

Despite of its relevance and evidence support, Cooperative Learning (CL) is a challenge for all the educational systems because of the difficulties for its implementation. This study has the objective to identify the effect of Primary Education initial teacher training in the prediction of future CL use. Two groups, of 44 and 45 students, were conceptually trained, with the latter also having the opportunity to experience CL in the university classroom. Opting for a mixed methods research, this study tries to identify changes in a pre- and post-test Cooperative Learning Implementation Questionnaire and to explain possible changes through 4 focus groups. Quantitative results show differences in expectations of CL success and index of CL use for the group who had the CL experience. Qualitative data revealed that improvements can be explained by the increase in students’ awareness of the learning opportunities that CL offered them, giving and receiving scaffold help, preparing activities and enhancing motivation

Compartir la enfermedad on-line: narrativas de restitución y búsqueda en blogs de mujeres con cáncer de mama

Artikulu honek bularreko minbizia duten zazpi emakumeren blogak aztertzen ditu haien testu eta irudietan gaixotasunari buruzko zein narratiba (Frank, 1995) nagusitzen den jakiteko.Gehienetan ageri den narratiba mota itzultze-narratiba da, zeinetan eriek medikuntzara jotzen baitute gaixotu aurreko egoerara itzultzeko. Blogetan bilatze elementuak ere badaude.Horietan erronka moduan azaltzen da gaitza eta minbiziak gorputzean uzten duen arrastoa erakusten da. Kaosaren teoriaren ausentziak baieztatu egiten du gaixotasunaren alderdi negatiboak onartzeko zailtasuna.; Distinguishing between restitution, chaos and quest narratives (Frank, 1995), this paper analyses which narratives prevail in 7 blogs written by women with breast cancer. The most present narrative is the restitution, in which patients turn to medicine with the aim of recovering their previous status. There are also examples of the quest narrative, when illness is seen as a challenge and visibility of the wounded body is claimed. The absence of chaos narrative confirms the cultural difficulty to acknowledge the negative aspects of illness.; Este artículo analiza 7 blogs de mujeres con cáncer de mama con el fin de observar qué narrativas de la enfermedad (Frank, 1995) predominan en sus textos e imágenes. La narrativa más presente es la de restitución, en la cual las pacientes recurren a la medicina para volver a su estado anterior. También se encuentran elementos de búsqueda, en los que la enfermedad se explica como un reto y se muestra el rastro del cáncer en el cuerpo. La ausencia de la narrativa del caos confirma la dificultad para asumir los aspectos negativos de la enfermedad

Magneto-ionic control of magnetism in two-oxide nanocomposite thin films comprising mesoporous cobalt ferrite conformally nanocoated with HfO2

Advances in nanotechnology require of robust methods to fabricate new types of nanostructured materials whose properties can be controlled at will using simple procedures. Nanoscale composites can benefit from actuation protocols that involve mutual interfacial interactions on the nanoscale. Herein, a method to create nanoscale composite thin films consisting of mesoporous cobalt ferrite (CFO) whose pore walls are nanocoated with HfO2 is presented. Porous CFO films are first prepared by sol-gel. Atomic layer deposition is subsequently used to conformally grow a HfO2 layer at the surface of the pore walls, throughout the thickness of the films. The magnetic properties of uncoated and HfO2-coated CFO mesoporous films are then modulated by applying external voltage, via magneto-ionic effects. The CFO-HfO2 composite films exhibit an enhanced magnetoelectric response. The magnetic moment at saturation of the composite increases 56% upon the application of −50 V (compared to 24% for CFO alone). Furthermore, dissimilar trends in coercivity are observed: after applying −50 V, the coercivity of the composite film increases by 69% while the coercivity of the CFO alone decreases by 25%. The effects can be reversed applying suitable positive voltages. This two-oxide nanocomposite material differs from archetypical magneto-ionic architectures, in which voltage-driven ion migration is induced between fully-metallic and oxide counterparts. The synthesized material is particularly appealing to develop new types of magnetoelectric devices with a highly tunable magnetic response

Polarization Switching and Light-Enhanced Piezoelectricity in Lead Halide Perovskites

We investigate the ferroelectric properties of photovoltaic methylammonium lead halide CH3NH3PbI3 perovskite using piezoelectric force microscopy (PFM) and macroscopic polarization methods. The electric polarization is clearly observed by amplitude and phase hysteresis loops. However, the polarization loop decreases as the frequency is lowered, persisting for a short time only, in the one second regime, indicating that CH3NH3PbI3 does not exhibit permanent polarization at room temperature. This result is confirmed by macroscopic polarization measurement based on a standard capacitive method. We have observed a strong increase of piezoelectric response under illumination, consistent with the previously reported giant photoinduced dielectric constant at low frequencies. We speculate that an intrinsic charge transfer photoinduced dipole in the perovskite cage may lie at the origin of this effect.Financial support from the Spanish Ministerio de Economia y Competitividad (MINECO) through RyC contracts 2013-12448 and 2011-07726 and projects MAT2013-47192-C3-1-R and MAT2012-3777

Epitaxial YBa2Cu3O7-x nanocomposite thin films from colloidal solutions

A methodology of general validity to prepare epitaxial nanocomposite films based on the use of colloidal solutions containing different crystalline preformed oxide nanoparticles (ex situ nanocomposites) is reported. The trifluoroacetate (TFA) metal-organic chemical solution deposition route is used with alcoholic solvents to grow epitaxial YBaCuO (YBCO) films. For this reason stabilizing oxide nanoparticles in polar solvents is a challenging goal. We have used scalable nanoparticle synthetic methodologies such as thermal and microwave-assisted solvothermal techniques to prepare CeO and ZrO nanoparticles. We show that stable and homogeneous colloidal solutions with these nanoparticles can be reached using benzyl alcohol, triethyleneglycol, nonanoic acid, trifluoroacetic acid or decanoic acid as protecting ligands, thereby allowing subsequent mixing with alcoholic TFA solutions. An elaborate YBCO film growth analysis of these nanocomposites allows the identification of the different relevant growth phenomena, e.g. nanoparticles pushing towards the film surface, nanoparticle reactivity, coarsening and nanoparticle accumulation at the substrate interface. Upon mitigation of these effects, YBCO nanocomposite films with high self-field critical currents (J ∼ 3-4 MA cm at 77 K) were reached, indicating no current limitation effects associated with epitaxy perturbation, while smoothed magnetic field dependences of the critical currents at high magnetic fields and decreased effective anisotropic pinning behavior confirm the effectiveness of the novel developed approach to enhance vortex pinning. In conclusion, a novel low cost solution-derived route to high current nanocomposite superconducting films and coated conductors has been developed with very promising features.All authors acknowledge the EU (EU-FP7 NMP-LA-2012-280432 EUROTAPES project). ICMAB acknowledges MINECO (MAT2014-51778-C2-1-R) and Generalitat de Catalunya (2014SGR 753 and Xarmae). UGhent acknowledges the Special Research Fund (BOF), the Research Foundation Flanders (FWO) and the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT). TEM microscopy work was conducted in the Catalan Institute of Nanoscience and Nanotechnology (ICN2). The authors acknowledge the ICN2 Electron Microscopy Division for offering access to their instruments and expertise. Part of the STEM microscopy work was conducted in 'Laboratorio de Microscopias Avanzadas' at the Instituto de Nanociencia de Aragon—Universidad de Zaragoza. The authors acknowledge the LMA-INA for offering access to their instruments and expertise. JG and MC also acknowledge the Ramon y Cajal program (RYC-2012-11709 and RYC-2013-12448 respectively).Peer Reviewe

On the Role of the Sr3−xCaxAl2O6 Sacrificial Layer Composition in Epitaxial La0.7Sr0.3MnO3 Membranes

The possibility to fabricate freestanding single crystal complex oxide films has raised enormous interest to be integrated in next-generation electronic devices envisaging distinct and novel properties that can deliver unprecedented performance improvement compared to traditional semiconductors. The use of the water-soluble SrAlO (SAO) sacrificial layer to detach the complex oxide film from the growth substrate has significantly expanded the complex oxide perovskite membranes library. Nonetheless, the extreme water sensitivity of SAO hinders its manipulation in ambient conditions and restricts the deposition approaches to those using high vacuum. This study presents a pioneering study on the role of Ca-substitution in solution processed SAO (SrCaAlO with x ⩽ 3) identifying a noticeable improvement on surface film crystallinity preserving a smooth surface morphology while favoring the manipulation in a less-restricted ambient conditions. Then, the study focuses on the effect of the sacrificial composition on the subsequent ex situ deposition of LaSrMnO (LSMO) by pulsed laser deposition, to obtain epitaxial films with a variable degree of strain. Finally, epitaxial and strain-free LSMO membranes with metal-insulator transition at 290 K are delivered. This study offers a hybrid and versatile approach to prepare and easily manipulate crystalline perovskite oxide membranes by facilitating ex situ growth on SAO-based sacrificial layer