A design layer to support self and social regulation processes of learning in MOOC

Open, social and networked approaches to learning pose challenges for learners, who must assume the role of actively directing their own learning, in interaction and collaboration with others, in an increasingly complex environment. In this context, concepts such as self-direction and self-regulation of learning have attracted renewed interest as umbrella terms for a skill set and provisions that allow subjects to independently guide their own learning process and assume responsibility for it. Moreover, many authors have pointed out various problems regarding MOOC design and quality from a pedagogical perspective. This raises the need for a greater and more holistic understanding of learning regulatory processes and for developing models and instruments to support learners in this regard. This research aims to analyse how to support learning regulation processes as a whole in MOOC environments. This means paying attention to both social and individual dimensions of regulation, by studying how processes of self-regulation, co-regulation and socially shared regulation can be supported and promoted in this type of learning contexts. To this end, we apply the methodology of design-based research in order to intervene directly in the pedagogical practice through an iterative cycle based on stages of design, intervention, reflection and redesign of a design layer to support learning regulation in a MOOC. In this paper we present the design of the regulation support layer proposed in the first research iteration. We begin by presenting its theoretical foundations and then describe the support layer that has been designed as well as the empirical case of an xMOOC were it has been implemented. Finally, some conclusions and recommendations for the design and practice of learning regulation in MOOC are drawn from the results obtained in the first research iteration

Activation mechanisms of the innate immune system: structure-function studies of interactions between death domains of MyD88 and IRAK proteins

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Bioquímica. Fecha de lectura: 27 de Noviembre de 2012

Hacia el aula virtual: actividades de enseñanza y aprendizaje en la red

Se presenta una definición práctica de aula virtual escolar presidida por la concepción de clases en las que se integre un ordenador con conexión a la red y se organice un plan de trabajo sistemático a diferentes niveles según los objetivos que se marquen para los alumnos. Más concretamente, se trataría de contar con un aula virtual dentro de la clase que ofreciera la posibilidad de preparar un conjunto de actividades útiles para el profesor y para los alumnos e integradas en el propio currículum escolar y que no fueran de tipo anecdótico o se realizaran de manera asistemática o a las que sólo accedieran unos cuantos. Cuando nos referimos a una aula virtual estamos pensando en un conjunto de actividades con un alto ingrediente comunicativo que de otro modo, es decir, sin la existencia del ordenador conectado a la red, no tendrían el sentido que adquiere en el contexto auténtico que proporciona la tecnología. Para ello se detallan hasta once metodologías docentes que pretenden orientar el trabajo de clase mediante el uso de esta aula virtual y entre las que se encuentran: las investigaciones virtuales, los proyectos telemáticos, las discusiones virtuales y el uso de hipertextos

Surface Glucan Structures in Aeromonas spp.

Aeromonas spp. are generally found in aquatic environments, although they have also been isolated from both fresh and processed food. These Gram-negative, rod-shaped bacteria are mostly infective to poikilothermic animals, although they are also considered opportunistic pathogens of both aquatic and terrestrial homeotherms, and some species have been associated with gastrointestinal and extraintestinal septicemic infections in humans. Among the different pathogenic factors associated with virulence, several cell-surface glucans have been shown to contribute to colonization and survival of Aeromonas pathogenic strains, in different hosts. Lipopolysaccharide (LPS), capsule and α-glucan structures, for instance, have been shown to play important roles in bacterial-host interactions related to pathogenesis, such as adherence, biofilm formation, or immune evasion. In addition, glycosylation of both polar and lateral flagella has been shown to be mandatory for flagella production and motility in different Aeromonas strains, and has also been associated with increased bacterial adhesion, biofilm formation, and induction of the host proinflammatory response. The main aspects of these structures are covered in this review

Evaluación de la educación digital y digitalización de la evaluación

Assessment and its digitalization are key elements of both online learning and emergency remote teaching. On its own, assessment is a complex subject, but add digital technology and this complexity increases tenfold. Far from a mechanical action, the assessment of online learning and the digitalization of this process involve more than just the incorporation of technological systems; as this special issue will show, they are concepts whose role in and impact on teaching must be understood at a pedagogical level. Based on empirical analysis and pedagogical reflection, the papers in this special issue seek to construct an irrefutably important line of work that poses the question, how does the digital environment transform sensitive processes such as ICT-mediated learning assessment and the assessment of online learning systems, and how do we in turn transform it? The issue tackles this question from four different angles: by highlighting the new digital demands placed on assessment in times of pandemic; the renewed role of educational feedback in the ICT-based self-regulated learning required; the need to move towards e-assessment as a guarantee of performance, and the evaluation of the quality of online learning as a watchdog mechanism. As the special issue on learning assessment shows, the topic is full of challenges, but that is the nature of the beast, so to speak, and how one must approach all things digital.La evaluación de la educación digital y digitalización de la evaluación son procesos por el que transita tanto la educación digital como la educación digital de emergencia. Aunque el tema de la evaluación, por sí misma, ya es complejo, esta complejidad aumenta cuando media la tecnología digital. Lejos de pensar que se trata de una acción técnica, la evaluación digital y la digitalización de la evaluación, como lo demuestra el contenido de este monográfico, no se reducen a la inserción de sistemas tecnológicos, sino a la comprensión pedagógica de su rol e impacto en los procesos educativos. Los trabajos que conforman este monográfico buscan contribuir, desde el análisis empírico y la reflexión pedagógica, a la construcción de una irremediable línea de trabajo que se pregunta: ¿cómo transforma, y transformamos, la condición digital, procesos tan sensibles como la evaluación del aprendizaje mediado y la evaluación de los sistemas educativos digitales? Al respecto, en este número se avanza en la respuesta en torno a cuatro núcleos. Por un lado, trabajos que ponen énfasis en la nueva exigencia digital impuesta a la evaluación en tiempos de pandemia, el papel renovado del feedback educativo en la necesaria autorregulación con soporte tecnológico, la necesidad de encarar con garantías la evaluación digital como condición de rendimiento y, como mecanismo observante, la evaluación de la calidad de la educación digital. Estos trabajos sobre evaluación educativa tienen poco de simple, mucho de complejo y bastante de complicado, pero esta es su naturaleza y con la que hay que entender el hecho digital

The Complete Structure of the Core Oligosaccharide from Edwardsiella tarda EIB 202 Lipopolysaccharide

The chemical structure and genomics of the lipopolysaccharide (LPS) core oligosaccharide of pathogenic Edwardsiella tarda strain EIB 202 were studied for the first time. The complete gene assignment for all LPS core biosynthesis gene functions was acquired. The complete structure of core oligosaccharide was investigated by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry MSn, and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry. The following structure of the undecasaccharide was established: The heterogeneous appearance of the core oligosaccharide structure was due to the partial lack of β-d-Galp and the replacement of α-d-GlcpNAcGly by α-d-GlcpNGly. The glycine location was identified by mass spectrometry

Polar glycosylated and lateral non-glycosylated flagella from Aeromonas hydrophila strain AH-1 (serotype O11)

Polar and but not lateral flagellin proteins from Aeromonas hydrophila strain AH-1 (serotype O11) were found to be glycosylated. Top-down mass spectrometry studies of purified polar flagellins suggested the presence of a 403 Da glycan of mass. Bottom-up mass spectrometry studies showed the polar flagellin peptides to be modified with 403 Da glycans in O-linkage. The MS fragmentation pattern of this putative glycan was similar to that of pseudaminic acid derivative. Mutants lacking the biosynthesis of pseudaminic acid (pseB and pseI homologues) were unable to produce polar flagella but no changes were observed in lateral flagella by post transcriptional regulation of the flagellin. Complementation was achieved by reintroduction of the wild type pseB and pseI. We compared two pathogenic features (adhesion to eukaryotic cells and biofilm production) between the wild type strain and two kinds of mutants: mutants lacking polar flagella glycosylation and lacking the O11-antigen lipopolysaccharide (LPS) but with unaltered polar flagella glycosylation. Results suggest that polar flagella glycosylation is extremely important for A. hydrophila AH-1 adhesion to Hep-2 cells and biofilm formation. In addition, we show the importance of the polar flagella glycosylation for immune stimulation of IL-8 production via toll 'like' receptor 5 TLR5

Sampling the conformational energy landscape of a hyperthermophilic protein by engineering key substitutions

Proteins exist as a dynamic ensemble of interconverting substates, which defines their conformational energy landscapes. Recent work has indicated that mutations that shift the balance between conformational substates (CSs) are one of the main mechanisms by which proteins evolve new functions. In the present study, we probe this assertion by examining phenotypic protein adaptation to extreme conditions, using the allosteric tetrameric lactate dehydrogenase (LDH) from the hyperthermophilic bacterium Thermus thermophilus (Tt) as a model enzyme. In the presence of fructose 1, 6 bis-phosphate (FBP), allosteric LDHs catalyze the conversion of pyruvate to lactate with concomitant oxidation of nicotinamide adenine dinucleotide, reduced form (NADH). The catalysis involves a structural transition between a low-affinity inactive 'T-state' and a high-affinity active 'R-state' with bound FBP. During this structural transition, two important residues undergo changes in their side chain conformations. These are R171 and H188, which are involved in substrate and FBP binding, respectively. We designed two mutants of Tt-LDH with one ('1-Mut') and five ('5-Mut') mutations distant from the active site and characterized their catalytic, dynamical, and structural properties. In 1-Mut Tt-LDH, without FBP, the KmPyr is reduced compared with that of the wild type, which is consistent with a complete shifting of the CS equilibrium of H188 to that observed in the R-state. By contrast, the CS populations of R171, kcat and protein stability are little changed. In 5-Mut Tt-LDH, without FBP, KmPyr approaches the values it has with FBP and becomes almost temperature independent, kcat increases substantially, and the CS populations of R171 shift toward those of the R-state. These changes are accompanied by a decrease in protein stability at higher temperature, which is consistent with an increased flexibility at lower temperature. Together, these results show that the thermal properties of an enzyme can be strongly modified by only a few or even a single mutation, which serve to alter the equilibrium and, hence, the relative populations of functionally important native-state CSs, without changing the nature of the CSs themselves. They also provide insights into the types of mutational pathways by which protein adaptation to temperature is achieved.</p

Structural characterization of core Region in Erwinia amylovora lipopolysaccharide.

Erwinia amylovora (E. amylovora) is the first bacterial plant pathogen described and demonstrated to cause fire blight, a devastating plant disease affecting a wide range of species including a wide variety of Rosaceae. In this study, we reported the lipopolysaccharide (LPS) core structure from E. amylovora strain CFBP1430, the first one for an E. amylovora highly pathogenic strain. The chemical characterization was performed on the mutants waaL (lacking only the O-antigen LPS with a complete LPS-core), wabH and wabG (outer-LPS core mutants). The LPSs were isolated from dry cells and analyzed by means of chemical and spectroscopic methods. In particular, they were subjected to a mild acid hydrolysis and/or a hydrazinolysis and investigated in detail by one and two dimensional Nuclear Magnetic Resonance (NMR) spectroscopy and ElectroSpray Ionization Fourier Transform-Ion Cyclotron Resonance (ESI FT-ICR) mass spectrometry