Measuring the influence of Cooperative Learning and Project Based Learning on problem solvin skill.

The aim of this study is to evaluate the effects obtained after applying two active learning methodologies (cooperative learning and project based learning) to the achievement of the competence problem solving. This study was carried out at the Technical University of Madrid, where these methodologies were applied to two Operating Systems courses. The first hypothesis tested was whether the implementation of active learning methodologies favours the achievement of ?problem solving?. The second hypothesis was focused on testing if students with higher rates in problem solving competence obtain better results in their academic performance. The results indicated that active learning methodologies do not produce any significant change in the generic competence ?problem solving? during the period analysed. Concerning this, we consider that students should work with these methodologies for a longer period, besides having a specific training. Nevertheless, a close correlation between problem solving self appraisal and academic performance has been detected.

Vibrations loads in the process of designing scientific spacecraft payloads

Scientific missions constitute fundamental cornerstones of space agencies such as ESA and NASA. Modern astronomy could not be understood without the data provided by these missions. Scientists need to design very carefully onboard instruments. Payloads have to survive the crucial launch moment and later perform well in the really harsh space environ-ment. It is very important that the instrument conceptual idea can be engineered to sustain all those loads

Diseño y desarrollo de un sistema basado en Learning Analytics para evaluar la competencia de trabajo en equipo.Design and development of a Learning Analytics System to evaluate group work competence

La adquisición de la competencia grupal es algo básico en la docencia universitaria. Esta tarea va a suponer evaluar diferentes factores en un número elevado de alumnos, lo que puede supone gran complejidad y un esfuerzo elevado. De cara a evitar este esfuerzo se puede pensar en emplear los registros de la interacción de los usuarios almacenados en las plataformas de aprendizaje. Para ello el presente trabajo se basa en el desarrollo de un sistema de Learning Analytics que es utilizado como herramienta para analizar las evidencias individuales de los distintos miembros de un equipo de trabajo. El trabajo desarrolla un modelo teórico apoyado en la herramienta, que permite relacionar las evidencias observadas de forma empírica para cada alumno, con indicadores obtenidos tanto de la acción individual como cooperativo de los miembros de un equipo realizadas a través de los foros de trabajo. Abstract — The development of the group work competence is something basic in university teaching. It should be evaluated, but this means to analyze different issues about the participation of a high number of students which is very complex and implies a lot of effort. In order to facilitate this evaluation it is possible to analyze the logs of students’ interaction in Learning Management Systems. The present work describes the development of a Learning Analytics system that analyzes the interaction of each of the members of working group. This tool is supported by a theoretical model, which allows establishing links between the empirical evidences of each student and the indicators of their action in working forums.

Histograms of oriented gradients for fast on-board vehicle verification

Histograms of Oriented Gradients (HoGs) provide excellent results in object detection and verification. However, their demanding processing requirements bound their applicability in some critical real-time scenarios, such as for video-based on-board vehicle detection systems. In this work, an efficient HOG configuration for pose-based on-board vehicle verification is proposed, which alleviates both the processing requirements and required feature vector length without reducing classification performance. The impact on classification of some critical configuration and processing parameters is in depth analyzed to propose a baseline efficient descriptor. Based on the analysis of its cells contribution to classification, new view-dependent cell-configuration patterns are proposed, resulting in reduced descriptors which provide an excellent balance between performance and computational requirements, rendering higher verification rates than other works in the literature.

Selection, training and validation process of a sensory panel for bread analysis: Influence of cultivar on the quality of breads made from common wheat and spelta wheat

A protocol of selection, training and validation of the members of the panel for bread sensory analysis is proposed to assess the influence of wheat cultivar on the sensory quality of bread. Three cultivars of bread wheat and two cultivars of spelt wheat organically-grown under the same edaphoclimatic conditions were milled and baked using the same milling and baking procedure. Through the use of triangle tests, differences were identified between the five breads. Significant differences were found between the spelt breads and those made with bread wheat for the attributes ?crumb cell homogeneity? and ?crumb elasticity?. Significant differences were also found for the odor and flavor attributes, with the bread made with ?Espelta Navarra? being the most complex, from a sensory point of view. Based on the results of this study, we propose that sensory properties should be considered as breeding criteria for future work on genetic improvement.

La memoria en el proceso creativo de Juan Muñoz = Memory in the creative process of Juan Muñoz

Esta tesis integra un estudio reflexivo sobre la relación de dependencia entre la creación y la memoria a través del análisis de la última obra del escultor Juan Muñoz: Double Bind (Tate Modern, Londres, 2001). Desde esta posición es obligado replantear el análisis de la obra, lo que hace necesario su estudio cubriendo el mayor espectro posible de información accesible más allá de la obra en sí, para aproximarse a la convergencia entre memoria y creación. La perspectiva de análisis propuesta abre camino a nuevas consideraciones so¬bre la relevancia del conocimiento en el desarrollo del proceso creativo. Este análisis no debe tan sólo suponer una aportación al conocimiento del trabajo de Juan Muñoz. Debe también desprenderse de él la innegable participación y necesaria lectura del pasado en el presente. La amnesia de los tiempos pasados impide completar el atlas de imágenes en las que se apoya la creación impidiendo el conocimiento del origen de las fuentes de inspi¬ración y las bases de la creación de una determinada obra. Este hecho limita y distorsiona sus posibles interpretaciones. Pretendo un acercamiento al entendimiento de la forma de mirar y de crear a través del tiempo que es memoria. La memoria tiene un cometido de crucial importancia para la actividad mental y juega un papel fundamental en la conducta y en la creación. La obra es el resultado de la búsqueda de una idea que exprese algo que el creador no puede ex¬presar de otra manera. Es la necesidad de expresar las ideas mediante un lenguaje que se desarrolla en el tiempo y en el espacio, reflejo del ser que responde al pensamiento. Es una forma de experiencia donde subyacen las sendas del pasado y donde se plantea el futuro. Sólo el creador accede a la obra desde dentro, el observador llega a ella desde el exterior y mediante su propia subjetividad. Las obras son formas de experiencia de sus autores, comunicar el mensaje de dicha experiencia supone por tanto interpretar. Persiguiendo la necesidad de saber y entender, pretender explicar el sentido de una cosa implica una apreciación intencionada asociada al entendimiento del intérprete. Las obras son produc¬tos que portan un mensaje y que contienen en su estructura las trazas del tiempo vivido por su creador. Si se quiere adquirir un acercamiento que represente la posición de un autor, será necesario no solo mirar a través de ella, si no introducirse en el contexto de su historia. Mirar hacia atrás, hacia la profundidad del presente para tener conciencia del pensamiento presente y futuro. Recorrer de este modo la instalación Double Bind de Juan Muñoz proporciona una síntesis de sus preocupaciones e intereses a la vez que aporta un conocimiento no necesariamente inmediato, pero relevante y trascendente de la obra, su creador y la historia. ABSTRACT This thesis comprises a reflective study of the dependence relationship between creation and memory through the analysis of the latest work by the sculptor Juan Muñoz: Double Bind (Tate Modern, London, 2001). From this position, it is mandatory to rethink the analysis of the work, making it necessary to cover the widest possible range of information available beyond the work itself, in order to obtain a closer view of the convergence between memory and creation. The proposed analytical approach opens up new considerations on the relevance of knowledge during the development of the creative process. This analysis should not only make a contribution to the knowledge of the work of Juan Muñoz. It should also infer the undeniable involvement and the necessary reading of the past in the present. Amnesia regarding past makes it impossible to complete the atlas of images on which the creation is based, blocking knowledge of the origin of the sources of inspiration and the basis for the creation of a specific work. This fact limits and distorts its possible interpretations. My intention is an approach to how to understand memory as the way of looking and creating over time. Memory has a crucial role to mental activity and plays a key role in behaviour and creation. The work is the result of finding an idea that expresses something that the creator can not express otherwise. It is the need to express ideas by means of a language that develops throughout time and space, a reflection of the being that responds to the thought. It is a way of experience underlying the paths of the past and where the future is set out. Only the creator can access the work from the inside. The observer sees it from the outside and in accordance with his/her own subjectivity. The works form a part of the experience of their authors, thus implying the interpretation of the message of their experience being passed on. The pursuit of knowledge and understanding, and trying to explain the meaning of something implies a deliberate appreciation associated with the understanding of the interpreter. The works are products bearing a message and containing in their structure traces of the time lived by their creator. If one wants to come close to what the author’s posture represents, it will not only be necessary to penetrate it, but also to introduce oneself into the context of its history. Take a look back, towards the depth of the present in order to become aware of present and future thinking. To go across the installation of Double Bind by Juan Muñoz in this way offers a synthesis of his concerns and interests while also providing a not necessarily immediate knowledge, but one which is relevant and important to the work, its creator and history.

Use of infrared thermography as a tool to monitor skin temperature along the recovery process of an anterior cruciate ligament surgery

Infrared thermography (IRT) is a safe and non-invasive tool used for examining physiological functions based on skin temperature (Tsk) control. Thermograms from 25 anterior cruciate ligament (ACL) surgically operated patients (2 female, 23 male) were taken with a FLIR infrared camera according to the protocol established by the International Academy of Clinical Thermology (IACT). This work consists of 4 studies. Studies 1 and 3 were related to establish the probable thermal difference among different moments of an ACL rupture after surgery: before starting the rehabilitation (P0), at the end of rehabilitation (P1) and 18 months from the end of rehabilitation (P2). For this purpose, on the other hand, studies 2 and 4 were related to establish the skin thermal difference (Tsk) between the injured and the non-injured leg in P0, P1 and P2. Results of the first study showed significant temperature increases in the posterior thigh area between P0 and P1 probably due to a compensatory mechanism. According to this, we can conclude that temperature of the posterior area of the injured and noninjured leg has increased from the first to the last day of the rehabilitation process. In the second study we found significant temperature differences between the injured and non-injured leg in both stages of rehabilitation (p<.01). On the one hand, the temperature of the injured leg is higher in the anterior view and the temperature of the non-injured leg is higher in the posterior view. By the time the patients had recovered from the reconstruction, thermal imbalances should have not been shown between symmetrical parts, but differences seemed to be still latent.. Study 3 shows that temperatures seem to be higher after a year and a half (P2) than in P1. Study 4 shows how thermal values 18 months later seemed to be normalized between both legs. No significant differences were found between the injured leg and the noninjured leg after one year and a half of the rehabilitation process. Considering results from Study 3 and 4 we can conclude that patients seemed to have recovered from a thermal point of view. The temperature in P2 was higher but symmetrical. RESUMEN La termografía infrarroja (IRT) es una herramienta segura y no invasiva utilizada para examinar funciones fisiológicas que se basan en el control de temperatura de la piel (Tsk). Termogramas de 25 pacientes intervenidos quirúrgicamente del ligamento cruzado anterior (LCA) (2 mujeres, 23 hombres) fueron tomadas con una cámara de infrarrojos FLIR de acuerdo con el protocolo establecido por la Academia Internacional de Termología Clínica (IACT). Este trabajo consiste en 4 estudios. Los estudios 1 y 3 describen la diferencia térmica entre los diferentes momentos tras la operación del ligamento cruzado anterior: antes de comenzar la rehabilitación (P0), al final de la rehabilitación (P1) y 18 meses tras finalizar la rehabilitación (P2). Por otra parte, los estudios 2 y 4 describen la diferencia de temperatura de la piel (Tsk) entre la pierna lesionada y la pierna no lesionada en P0, P1 y P2. Los resultados del primer estudio mostraron aumentos significativos de temperatura en la zona posterior de los muslos entre P0 y P1, probablemente debido a un mecanismo de compensación. De acuerdo con esto, se puede concluir que la temperatura de la zona posterior de la pierna lesionada y no lesionada se ha incrementado desde el primero hasta el último día del proceso de rehabilitación. En el segundo estudio se encontraron diferencias significativas de temperatura entre la pierna lesionada y no lesionada en ambas etapas de la rehabilitación (p<.01). Por un lado, la temperatura de la pierna lesionada es mayor en la vista anterior. Por otro lado, la temperatura de la pierna no lesionada es mayor en la vista posterior. Una vez que los pacientes se han recuperado de todo el proceso, no deberían existir desequilibrios térmicos entre partes simétricas del cuerpo, pero las diferencias todavía estaban latentes. El tercer estudio muestra que la temperatura es más alta en P2 que en P1. El cuarto estudio muestra cómo los valores térmicos entre ambas piernas en P2 se han normalizado entre ambas piernas. No se encontraron diferencias significativas entre la pierna lesionada y la pierna no lesionada después de 18 meses tras el proceso de rehabilitación. Considerando los resultados del studio 3 y 4, podemos concluir que se ha llegado a la recuperación total desde un punto de vista térmico. La temperatura es más elevada en P2 pero simétrica.

Evaluation of the PV cell operation temperature in the process of fast switching to open-circuit mode

A procedure for measuring the overheating temperature (ΔT ) of a p-n junction area in the structure of photovoltaic (PV) cells converting laser or solar radiations relative to the ambient temperature has been proposed for the conditions of connecting to an electric load. The basis of the procedure is the measurement of the open-circuit voltage (VO C ) during the initial time period after the fast disconnection of the external resistive load. The simultaneous temperature control on an external heated part of a PV module gives the means for determining the value of VO C at ambient temperature. Comparing it with that measured after switching OFF the load makes the calculation of ΔT possible. Calibration data on the VO C = f(T ) dependences for single-junction AlGaAs/GaAs and triple-junction InGaP/GaAs/Ge PV cells are presented. The temperature dynamics in the PV cells has been determined under flash illumination and during fast commutation of the load. Temperature measurements were taken in two cases: converting continuous laser power by single-junction cells and converting solar power by triple-junction cells operating in the concentrator modules.

Mechanical behaviour and formation process of silkworm silk gut

High performance silk fibers were produced directly from the silk glands of silkworms ("Bombyx mori") following an alternative route to natural spinning. This route is based on a traditional procedure that consists of soaking the silk glands in a vinegar solution and stretching them by hand leading to the so called silkworm guts. Here we present, to the authors’ best knowledge, the first comprehensive study on the formation, properties and microstructure of silkworm gut fibers. Comparison of the tensile properties and microstructural organization of the silkworm guts with those of naturally spun fibers allows gain of a deeper insight into the mechanisms that lead to the formation of the fiber, as well as the relationship between the microstructure and properties of these materials. In this regard, it is proved that an acidic environment and subsequent application of tensile stress in the range of 1000 kPa are sufficient conditions for the formation of a silk fiber.

Administration of helper-dependent adenoviral vectors and sequential delivery of different vector serotype for long-term liver-directed gene transfer in baboons

The efficiency of first-generation adenoviral vectors as gene delivery tools is often limited by the short duration of transgene expression, which can be related to immune responses and to toxic effects of viral proteins. In addition, readministration is usually ineffective unless the animals are immunocompromised or a different adenovirus serotype is used. Recently, adenoviral vectors devoid of all viral coding sequences (helper-dependent or gutless vectors) have been developed to avoid expression of viral proteins. In mice, liver-directed gene transfer with AdSTK109, a helper-dependent adenoviral (Ad) vector containing the human α1-antitrypsin (hAAT) gene, resulted in sustained expression for longer than 10 months with negligible toxicity to the liver. In the present report, we have examined the duration of expression of AdSTK109 in the liver of baboons and compared it to first-generation vectors expressing hAAT. Transgene expression was limited to approximately 3–5 months with the first-generation vectors. In contrast, administration of AdSTK109 resulted in transgene expression for longer than a year in two of three baboons. We have also investigated the feasibility of circumventing the humoral response to the virus by sequential administration of vectors of different serotypes. We found that the ineffectiveness of readministration due to the humoral response to an Ad5 first-generation vector was overcome by use of an Ad2-based vector expressing hAAT. These data suggest that long-term expression of transgenes should be possible by combining the reduced immunogenicity and toxicity of helper-dependent vectors with sequential delivery of vectors of different serotypes.

Electrical stimulation of neonatal cardiomyocytes results in the sequential activation of nuclear genes governing mitochondrial proliferation and differentiation

Electrical stimulation of neonatal cardiac myocytes produces hypertrophy and cellular maturation with increased mitochondrial content and activity. To investigate the patterns of gene expression associated with these processes, cardiac myocytes were stimulated for varying times up to 72 hr in serum-free culture. The mRNA contents for genes associated with transcriptional activation [c-fos, c-jun, JunB, nuclear respiratory factor 1 (NRF-1)], mitochondrial proliferation [cytochrome c (Cyt c), cytochrome oxidase], and mitochondrial differentiation [carnitine palmitoyltransferase I (CPT-I) isoforms] were measured. The results establish a temporal pattern of mRNA induction beginning with c-fos (0.25–3 hr) and followed sequentially by c-jun (0.5–3 hr), JunB (0.5–6 hr), NRF-1 (1–12 hr), Cyt c (12–72 hr), and muscle-specific CPT-I (48–72 hr). Induction of the latter was accompanied by a marked decrease in the liver-specific CPT-I mRNA, thus supporting the developmental fidelity of this pattern of gene regulation. Consistent with a transcriptional mechanism, electrical stimulation increased c-fos, β-myosin heavy chain, and Cyt c promoter activities. These increases coincided with a rise in their respective endogenous gene transcripts. NRF-1, cAMP response element, and Sp-1 site mutations within the Cyt c promoter reduced luciferase expression in both stimulated and nonstimulated myocytes. Mutations in the NRF-1 and CRE sites inhibited the induction by electrical stimulation (5-fold and 2-fold, respectively) whereas mutation of the Sp-1 site maintained or increased the fold induction. This finding is consistent with the appearance of NRF-1 and fos/jun mRNAs prior to that of Cyt c and suggests that induction of these transcription factors is a prerequisite for the transcriptional activation of Cyt c expression. These results support a regulatory role for NRF-1 and possibly AP-1 in the initiation of mitochondrial proliferation.

Sequential mechanism of solubilization and refolding of stable protein aggregates by a bichaperone network

A major activity of molecular chaperones is to prevent aggregation and refold misfolded proteins. However, when allowed to form, protein aggregates are refolded poorly by most chaperones. We show here that the sequential action of two Escherichia coli chaperone systems, ClpB and DnaK-DnaJ-GrpE, can efficiently solubilize excess amounts of protein aggregates and refold them into active proteins. Measurements of aggregate turbidity, Congo red, and 4,4′-dianilino-1,1′-binaphthyl-5,5′-disulfonic acid binding, and of the disaggregation/refolding kinetics by using a specific ClpB inhibitor, suggest a mechanism where (i) ClpB directly binds protein aggregates, ATP induces structural changes in ClpB, which (ii) increase hydrophobic exposure of the aggregates and (iii) allow DnaK-DnaJ-GrpE to bind and mediate dissociation and refolding of solubilized polypeptides into native proteins. This efficient mechanism, whereby chaperones can catalytically solubilize and refold a wide variety of large and stable protein aggregates, is a major addition to the molecular arsenal of the cell to cope with protein damage induced by stress or pathological states.

Sequential Actions of Phospholipase D and Phosphatidic Acid Phosphohydrolase 2b Generate Diglyceride in Mammalian Cells

Phosphatidylcholine (PC) is a major source of lipid-derived second messenger molecules that function as both intracellular and extracellular signals. PC-specific phospholipase D (PLD) and phosphatidic acid phosphohydrolase (PAP) are two pivotal enzymes in this signaling system, and they act in series to generate the biologically active lipids phosphatidic acid (PA) and diglyceride. The identity of the PAP enzyme involved in PLD-mediated signal transduction is unclear. We provide the first evidence for a functional role of a type 2 PAP, PAP2b, in the metabolism of PLD-generated PA. Our data indicate that PAP2b localizes to regions of the cell in which PC hydrolysis by PLD is taking place. Using a newly developed PAP2b-specific antibody, we have characterized the expression, posttranslational modification, and localization of endogenous PAP2b. Glycosylation and localization of PAP2b appear to be cell type and tissue specific. Biochemical fractionation and immunoprecipitation analyses revealed that PAP2b and PLD2 activities are present in caveolin-1–enriched detergent-resistant membrane microdomains. We found that PLD2 and PAP2b act sequentially to generate diglyceride within this specialized membrane compartment. The unique lipid composition of these membranes may provide a selective environment for the regulation and actions of enzymes involved in signaling through PC hydrolysis.

Due process of law / Adhemar Ferreira Maciel. --

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