La competencia "aprender a aprender" en un contexto educativo de ingeniería

The objective of this thesis was to establish bases to characterize "learn to learn" competence and to promote it in an engineering educational context. It adopted the vision of educational psychology that establishes self-regulation in learning as the operative manifestation of this competence. The research was developed in three phases: obtaining a psychometric tool to characterize self-regulation in learning; the characterization of self-regulation in learning of the students; and, based on the results of the characterization, an educational intervention was designed, implemented and evaluated to facilitate that students use the learning strategy of selection and organization of the information . In the first phase in order to obtain the psychometric tool was translated, adapted and validated the Motivated Strategies for Learning Questionnaire - MSLQ following the guidelines of the International Test Commission (ITC). The result was the MSLQ-Colombia. With the participation of 1218 students and 12 engineering professors, the psychometric properties of MSLQ-Colombia were studied: construct validity, content validity, external validity and reliability; the MSLQ-Colombia was valid and reliable. In the characterization, second phase, the self-regulation of the motivation and the use of learning strategies of 1268 students were evaluated. It was found that students self-regulate their motivation highly: beliefs about learning control and task value were the aspects most self-regulated, while the learning orientation toward extrinsic goals and anxiety in the assessment were the least self-regulated. It was found that students used learning strategies in a non-uniform way, there were strategies frequently used and others occasionally used. The three strategies most used were the monitoring of learning, control of the place of study and effort regulation; the strategies least used were time management and selection and organization of information. The results of this phase also allowed to propose a new hypothesis to investigate the self-regulation in the learning: the self-regulation of some aspects of the motivation and the use of some strategies depend on the subject that the students are coursing; on the contrary, other aspects of motivation and other learning strategies do not depend on the subject. Educational intervention, the third phase, consisted in offering instruction at students on summarizing technique to facilitate them to select and organize the information of engineering technical texts; in addition, students practiced the production of abstracts and the teachers provided them feedback on the quality of these abstracts. The effects of the educational intervention were explored with a quasi-experimental investigation (experimental group: 177 students, control group: 65 students) that collected quantitative and qualitative evidences. The educational intervention facilitated that students increase positive and significantly, in a statistical sense, the writing of abstracts to select and organize the information; the quality of the abstracts also significantly improved. The intervention also impacted the use of strategies such as metacognition and resource management as time management. The results of this thesis provide solutions to the current problems of the "learn to learn" competence: practical contributions such as the MSLQ-Colombia and the didactic sequence of the educational intervention, empirical contributions such as the psychometric indexes of MSLQ-Colombia, the characterization of the self-regulation in learning of students and the impacts of educational intervention. Finally, this thesis sets a new integrative approach (hypothesis) of the previous ones about the research on the self-regulation in learning.El objetivo de esta Tesis fue establecer bases para caracterizar la competencia "aprender a aprender" y potenciarla en un contexto educativo de ingeniería. Se adoptó la visión de la psicología educativa que instaura la autorregulación en el aprendizaje como la manifestación operativa de esta competencia. La investigación se desarrolló en tres fases: obtención de una herramienta psicométrica para caracterizar la autorregulación en el aprendizaje; caracterización de la autorregulación en el aprendizaje de los estudiantes; y, a partir de los resultados de la caracterización, se diseñó, implementó y evaluó una intervención educativa para facilitar a los estudiantes usar la estrategia de aprendizaje selección y organización de la información. En la primera fase para obtener la herramienta psicométrica se tradujo, adaptó y validó el Motivated Strategies for Learning Questionnaire - MSLQ siguiendo las directrices de la International Test Commission (ITC). El resultado fue el MSLQ-Colombia. Con la participación de 1218 estudiantes y 12 profesores de ingeniería se estudiaron las propiedades psicométricas del MSLQ-Colombia: validez de constructo, validez de contenido, validez externa y confiabilidad; el MSLQ-Colombia resultó válido y confiable. En la caracterización, segunda fase, se valoró la autorregulación de la motivación y el uso de estrategias de aprendizaje de 1268 estudiantes. Se encontró que los estudiantes autorregulaban altamente su motivación: las creencias de control del aprendizaje y la valoración de la tarea fueron los aspectos que más autorregularon, mientras que la orientación del aprendizaje hacia metas extrínsecas y la ansiedad en la evaluación fueron los menos autorregulados. Se halló que los estudiantes usaban estrategias de aprendizaje de manera no uniforme, hubo estrategias de uso frecuente y otras de uso ocasional. Las tres estrategias más usadas fueron el monitoreo del aprendizaje, control del lugar de estudio y regulación del esfuerzo; las menos usadas fueron la gestión del tiempo y selección y organización de la información. Los resultados de esta fase también permitieron plantear una nueva hipótesis para investigar la autorregulación en el aprendizaje: la autorregulación de algunos aspectos de la motivación y el uso de algunas estrategias dependen de la asignatura que los estudiantes están cursando; por el contrario, otros aspectos de la motivación y otras estrategias de aprendizaje no dependen de la asignatura. La intervención educativa, tercera fase, consistió en ofrecer a los estudiantes instrucción sobre la técnica de resumir para facilitarles seleccionar y organizar la información de textos técnicos de ingeniería; asimismo, los estudiantes elaboraron resúmenes y se les brindó realimentación sobre la calidad de dichos resúmenes. Los efectos de la intervención educativa se exploraron con una investigación cuasi-experimental (grupo experimental: 177 estudiantes, grupo control: 65 estudiantes) que recolectó evidencias cuantitativas y cualitativas. La intervención educativa facilitó que los estudiantes incrementaran positiva y significativamente, en sentido estadístico, la escritura de resúmenes para seleccionar y organizar la información; los estudiantes también mejoraron significativamente la calidad de los resúmenes. La intervención también impactó el uso de estrategias como la metacognición y la administración de recursos como gestión del tiempo. Los resultados de esta Tesis aportan soluciones a las problemáticas actuales de la competencia "aprender a aprender": contribuciones prácticas como el MSLQ-Colombia y la secuencia didáctica de la intervención educativa; contribuciones empíricas como los índices psicométricos del MSLQ-Colombia, la caracterización de la autorregulación del aprendizaje de los estudiantes y los impactos de la intervención educativa. Por último, esta Tesis establece un nuevo enfoque (hipótesis) integrador de los anteriores en la investigación de la autorregulación del aprendizaje

Tunable Generation of Correlated Vortices in Open Superconductor Tubes

As shown theoretically, geometry determines the dynamics of vortices in the presence of transport currents in open superconductor micro- and nanotubes subject to a magnetic field orthogonal to the axis. In low magnetic fields, vortices nucleate periodically at one edge of the tube, subsequently move along the tube under the action of the Lorentz force and denucleate at the opposite edge of the tube. In high magnetic fields, vortices pass along rows closest to the slit. Intervortex correlations lead to an attraction between vortices moving at opposite sides of a tube. Open superconductor nanotubes provide a tunable generator of superconducting vortices for fluxon-based quantum computing

Wastewater Mediated Activation of Micromotors for Efficient Water Cleaning

We present wastewater-mediated activation of catalytic micromotors for the degradation of nitroaromatic pollutants in water. These next-generation hybrid micromotors are fabricated by growing catalytically active Pd particles over thin-metal films (Ti/Fe/Cr), which are then rolled-up into self-propelled tubular microjets. Coupling of catalytically active Pd particles inside the micromotor surface in the presence of a 4-nitrophenol pollutant (with NaBH₄ as reductant) results in autonomous motion via the bubble–recoil propulsion mechanism such that the target pollutant mixture (wastewater) is consumed as a fuel, thereby generating nontoxic byproducts. This study also offers several distinct advantages over its predecessors including no pH/temperature manipulation, limited stringent process control and complete destruction of the target pollutant mixture. The improved intermixing ability of the micromotors caused faster degradation ca. 10 times higher as compared to its nonmotile counterpart. The high catalytic efficiency obtained via a wet-lab approach has promising potential in creating hybrid micromotors comprising of multicatalytic systems assembled into one entity for sustainable environmental remediation and theranostics

Wastewater Mediated Activation of Micromotors for Efficient Water Cleaning

We present wastewater-mediated activation of catalytic micromotors for the degradation of nitroaromatic pollutants in water. These next-generation hybrid micromotors are fabricated by growing catalytically active Pd particles over thin-metal films (Ti/Fe/Cr), which are then rolled-up into self-propelled tubular microjets. Coupling of catalytically active Pd particles inside the micromotor surface in the presence of a 4-nitrophenol pollutant (with NaBH₄ as reductant) results in autonomous motion via the bubble–recoil propulsion mechanism such that the target pollutant mixture (wastewater) is consumed as a fuel, thereby generating nontoxic byproducts. This study also offers several distinct advantages over its predecessors including no pH/temperature manipulation, limited stringent process control and complete destruction of the target pollutant mixture. The improved intermixing ability of the micromotors caused faster degradation ca. 10 times higher as compared to its nonmotile counterpart. The high catalytic efficiency obtained via a wet-lab approach has promising potential in creating hybrid micromotors comprising of multicatalytic systems assembled into one entity for sustainable environmental remediation and theranostics

Tunable Generation of Correlated Vortices in Open Superconductor Tubes

As shown theoretically, geometry determines the dynamics of vortices in the presence of transport currents in open superconductor micro- and nanotubes subject to a magnetic field orthogonal to the axis. In low magnetic fields, vortices nucleate periodically at one edge of the tube, subsequently move along the tube under the action of the Lorentz force and denucleate at the opposite edge of the tube. In high magnetic fields, vortices pass along rows closest to the slit. Intervortex correlations lead to an attraction between vortices moving at opposite sides of a tube. Open superconductor nanotubes provide a tunable generator of superconducting vortices for fluxon-based quantum computing

Tunable Generation of Correlated Vortices in Open Superconductor Tubes

As shown theoretically, geometry determines the dynamics of vortices in the presence of transport currents in open superconductor micro- and nanotubes subject to a magnetic field orthogonal to the axis. In low magnetic fields, vortices nucleate periodically at one edge of the tube, subsequently move along the tube under the action of the Lorentz force and denucleate at the opposite edge of the tube. In high magnetic fields, vortices pass along rows closest to the slit. Intervortex correlations lead to an attraction between vortices moving at opposite sides of a tube. Open superconductor nanotubes provide a tunable generator of superconducting vortices for fluxon-based quantum computing

Tunable Generation of Correlated Vortices in Open Superconductor Tubes

As shown theoretically, geometry determines the dynamics of vortices in the presence of transport currents in open superconductor micro- and nanotubes subject to a magnetic field orthogonal to the axis. In low magnetic fields, vortices nucleate periodically at one edge of the tube, subsequently move along the tube under the action of the Lorentz force and denucleate at the opposite edge of the tube. In high magnetic fields, vortices pass along rows closest to the slit. Intervortex correlations lead to an attraction between vortices moving at opposite sides of a tube. Open superconductor nanotubes provide a tunable generator of superconducting vortices for fluxon-based quantum computing

Self-Propelled Micromotors for Cleaning Polluted Water

We describe the use of catalytically self-propelled microjets (dubbed micromotors) for degrading organic pollutants in water <i>via</i> the Fenton oxidation process. The tubular micromotors are composed of rolled-up functional nanomembranes consisting of Fe/Pt bilayers. The micromotors contain double functionality within their architecture, <i>i</i>.<i>e</i>., the inner Pt for the self-propulsion and the outer Fe for the <i>in situ</i> generation of ferrous ions boosting the remediation of contaminated water.The degradation of organic pollutants takes place in the presence of hydrogen peroxide, which acts as a reagent for the Fenton reaction and as main fuel to propel the micromotors. Factors influencing the efficiency of the Fenton oxidation process, including thickness of the Fe layer, pH, and concentration of hydrogen peroxide, are investigated. The ability of these catalytically self-propelled micromotors to improve intermixing in liquids results in the removal of organic pollutants <i>ca.</i> 12 times faster than when the Fenton oxidation process is carried out without catalytically active micromotors. The enhanced reaction–diffusion provided by micromotors has been theoretically modeled. The synergy between the internal and external functionalities of the micromotors, without the need of further functionalization, results into an enhanced degradation of nonbiodegradable and dangerous organic pollutants at small-scale environments and holds considerable promise for the remediation of contaminated water

Self-Propelled Micromotors for Cleaning Polluted Water

We describe the use of catalytically self-propelled microjets (dubbed micromotors) for degrading organic pollutants in water <i>via</i> the Fenton oxidation process. The tubular micromotors are composed of rolled-up functional nanomembranes consisting of Fe/Pt bilayers. The micromotors contain double functionality within their architecture, <i>i</i>.<i>e</i>., the inner Pt for the self-propulsion and the outer Fe for the <i>in situ</i> generation of ferrous ions boosting the remediation of contaminated water.The degradation of organic pollutants takes place in the presence of hydrogen peroxide, which acts as a reagent for the Fenton reaction and as main fuel to propel the micromotors. Factors influencing the efficiency of the Fenton oxidation process, including thickness of the Fe layer, pH, and concentration of hydrogen peroxide, are investigated. The ability of these catalytically self-propelled micromotors to improve intermixing in liquids results in the removal of organic pollutants <i>ca.</i> 12 times faster than when the Fenton oxidation process is carried out without catalytically active micromotors. The enhanced reaction–diffusion provided by micromotors has been theoretically modeled. The synergy between the internal and external functionalities of the micromotors, without the need of further functionalization, results into an enhanced degradation of nonbiodegradable and dangerous organic pollutants at small-scale environments and holds considerable promise for the remediation of contaminated water

Closed-loop control of a self-propelled microjet using the sliding-mode control law (5).

<p>The microjet moves towards a reference position (small blue circle) under the influence of the self-propulsion force and the magnetic fields. The generated magnetic fields using our sliding-mode control system orients the microjet along the magnetic field lines. The microjet moves along these lines using its propulsion force. In this representative experiment, the control system positions the microjet at an average velocity of 90 m/s, and within a region-of-convergence of 260 m in diameter. The controller gains are: and . The large blue circle is assigned by our feature tracking software <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0083053#pone.0083053-Keuning1" target="_blank">[14]</a> and the red line represents the velocity vector of the microjet. The inset shows a Scanning Electron Microscopy image of a microjet fixed to its substrate.</p