Graphene-based electrodes for silicon heterojunction solar cell technology

Transparent conductive electrodes based on graphene have been previously proposed as an attractive candidate for optoelectronic devices. While graphene alone lacks the antireflectance properties needed in many applications, it can still be coupled with traditional transparent conductive oxides, further enhancing their electrical performance. In this work, the effect of combining indium tin oxide with between one and three graphene monolayers as the top electrode in silicon heterojunction solar cells is analyzed. Prior to the metal grid deposition, the electrical conductance of the hybrid electrodes was evaluated through reflection-mode terahertz time-domain spectroscopy. The obtained conductance maps showed a clear electrical improvement with each additional graphene sheet. In the electrical characterization of the finished solar cells, this translated to a meaningful reduction in the series resistance and an increase in the devices’ fill factor. On the other hand, each additional sheet absorbs part of the incoming radiation, causing the short circuit current to simultaneously decrease. Consequently, additional graphene monolayers past the first one did not further enhance the efficiency of the reference cells. Ultimately, the increase obtained in the fill factor endorses graphene-based hybrid electrodes as a potential concept for improving solar cells’ efficiency in future novel designs.This research was funded by DIGRAFEN, grant number ENE2017–88065-C2-2-R. The APC was funded by the Ministry of Economy, Industry and Competitiveness from Spain. das-Nano and UPNA would also like to acknowledge the funding from the Government of Navarra and the European Regional Development Fund (ERDF), 2020 I + D projects: ref. 0011-1365-2020-000026 for das-Nano and ref. 0011-1365-2020-000045 for UPNA

Influencers pedagógicos en el grado de educación infantil: una experiencia de innovación educativa / Pedagogical influencers in the degree of early childhood education: an experience of educational innovation

En este trabajo se desarrolla la idea de los estudiantes como influencers pedagógicos, es decir, los estudiantes como personas de "autoridad" suficiente para que el mensaje que transmiten a otros estudiantes sea reconocido y valorado para su formación. Concretamente, el objetivo de este trabajo es describir la experiencia de innovación educativa desarrollada con los futuros maestros de Educación Infantil (estudiantes de último curso) de la Universidad de Murcia (España).Se trata de un estudio eminentemente descriptivo, desarrollado desde un paradigma complementarista donde el principal interés es determinar la valoración que hacen los estudiantes sobre la experiencia realizada y comprender la naturaleza de tales valoraciones y sus propuestas de mejora.El hallazgo principal del estudio es la constatación de evidencias empíricas que avalan que el desarrollo de un papel activo por parte de los estudiantes en su proceso aprendizaje actúa como elemento diferenciador en su posicionamiento y valoración de la enseñanza recibida. Esto, unido a la utilización de las TIC y las redes sociales, hacen que la experiencia de innovación educativa realizada haya sido altamente valorada por los estudiantes. 

Actuador con mecanismo de rigidez variable y par umbral

Número de publicación: ES2387228 A1 (18.09.2012) También publicado como: ES2387228 B2 (05.02.2013) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P201200712 (29.06.2012)Actuador con mecanismo de rigidez variable y par umbral, del tipo de los utilizados en articulaciones de revolución de brazos robóticos y que pueden modificar su rigidez. El actuador incorpora un motor (1) que se encarga de controlar la posición de equilibrio del eslabón de salida (13). El mecanismo contiene un resorte (18) y una palanca (12). La rigidez del mecanismo puede ser modificada variando la posición de esta palanca (12) mediante un motor (14). Dicha rigidez determina el valor del giro entre la posición de la polea (2) solidaria al eje de salida del motor (1) y la posición del eslabón (13). Dos tensores (5) y (6) permiten modificar la precarga de dos cables (3) y (4) respectivamente, de forma que el mecanismo no entra en funcionamiento hasta que no se ha sobrepasado un cierto valor de par sobre la articulación.Universidad de Almerí

Application of propolis extract, nanovitamin C and nanovitamin E to prevent alveolar osteitis after impacted lower third molar surgery. A randomized, double-blind, split-mouth, pilot study

Propolis has anti-inflammatory, analgesic and healing properties. The purpose of this study was to determine whether a gel containing 2% of propolis extract, 0.2% of ascorbic acid and 0.2% of tocopherol acetate is effective in preventing surgical complications related to impacted lower third molar extractions. A randomized, double-blind, split-mouth study was performed. Fifteen patients were recruited who needed bilateral impacted lower third molar extractions with a similar surgical difficulty. A test or placebo gel was administered randomly inside post-extraction sockets. Each patient was instructed to apply the gel 3 times/day in the surgical wound for a week. After a month, the contralateral third molar was extracted, and the opposite gel applied. The following parameters were diagnosed/evaluated and then recorded: alveolar osteitis following Blum?s criteria, swelling and trismus at day one, two, three and seven post-intervention, wound healing at day 7 post-intervention, and postoperative pain using a visual analog scale, as well as, the number of analgesic pill intake. A total of twenty-six surgical procedures were performed in 13 patients (mean age 20.67±2 years). Alveolar osteitis was reported in 3 patients from the placebo group (23.1%) and none in the test group (0%) (p=0.25). No statistically significant differences were reported in swelling, trismus, wound healing or analgesic pill consumption between two groups. But statistically lower postoperative pain during the 7 days after surgical extractions was found according to visual analog scale in test group compared to the placebo group (p=0.007). No side effects were reported. The application of this gel may be effective in preventing alveolitis and thus reducing postoperative pain after impacted third molar extractions. More randomized clinical trials with larger sample are needed to confirm these results

Time delay evaluation on thewater-leaving irradiance retrieved from empirical models and satellite imagery

Temporal delays and spatial randomness between ground-based data and satellite overpass involve important deviations between the empirical model output and real data; these are factors poorly considered in the model calibration. The inorganic matter-generated turbidity in Lake Chapala (Mexico) was taken as a study case to expose the influence of such factors. Ground-based data from this study and historical records were used as references. We take advantage of the at-surface reflectance from Landsat-8, sun-glint corrections, a reduced NIR-band range, and null organic matter incidence in these wavelengths to diminish the physical phenomena-related radiometric artifacts; leaving the spatio-temporal relationships as the principal factor inducing the model uncertainty. Non-linear correlations were assessed to calibrate the best empirical model; none of them presented a strong relationship (<73%), including that based on hourly delays. This last model had the best predictability only for the summer-fall season, explaining 71% of the turbidity variation in 2016, and 59% in 2017, with RMSEs < 24%. The instantaneous turbidity maps depicted the hydrodynamic complexity of the lake, highlighting a strong component of spatial randomness associated with the temporal delays. Reasonably, robust empirical models will be developed if several dates and sampling-sites are synchronized with more satellite overpasses.</p

Megatsunamis Induced by Volcanic Landslides in the Canary Islands: Age of the Tsunami Deposits and Source Landslides

Evidence for frequent, large landslides on the flanks of the volcanic edifices forming the Canary Islands include outstanding landslide scars and their correlative submarine and subaerial rock and debris avalanche deposits. These landslides involved volumes ranging from tens to hundreds of km3. The sudden entry of large volumes of rock masses in the sea may have triggered tsunamis capable of affecting the source and neighboring islands, with the resulting huge waves dragging coastal and seabed materials and fauna and redepositing them inland. Here, we present new geological evidence and geochronological data of at least five megatsunamis in Tenerife, Lanzarote, and Gran Canaria, triggered by island flank megalandslides, and occasionally explosive eruptions, during the last 1 million years. The exceptional preservation of the megatsunami deposits and the large area they cover, particularly in Tenerife, provide fundamental data on the number of tsunami events and run-ups, and allow proposals on the sources and age of the tsunamis. Tsunami run-up heights up to 290 m above coeval sea level, some of the highest known on Earth in recent geological times, were estimated based on sedimentological, geomorphological, paleontological, and geochronological data. The research results made it possible to estimate the recurrence of tsunamis in the archipelago during the last hundreds of thousands of years, and to establish relationships between tsunami deposits and the probable triggering island flank landslides.info:eu-repo/semantics/publishedVersio

Primer registro de anomalía intersexual gonadal de Trachurus mediterraneus (Steindachner, 1868) desde el Mar de Alborán.

El objetivo principal de este trabajo es dar a conocer el primer registro de una anomalía intersexual gonadal de Trachurus mediterraneus desde el mar de Alborán (Mediterráneo occidental). Este espécimen es el primer registro de intersexualidad para un jurel en el mundo.Postprin

Primer registro de anomalía intersexual gonadal de Trachurus mediterraneus (Steindachner, 1868) desde el mar de Alborán

First record of intersexuality gonad anomaly in Trachurus mediterraneus (Steindachner, 1868) from Alboran SeaEl objetivo principal de este trabajo es dar a conocer el primer registro de una anomalía intersexual gonadal de Trachurus mediterraneus desde el mar de Alborán (Mediterráneo occidental). Este espécimen es el primer registro de intersexualidad para un jurel en el mundo

Determinantes psicosociales y deportivos de la intención de continuar la participación en la práctica deportiva y la competición en atletas con discapacidad

Las experiencias de flow, la competencia deportiva percibida y la pasión han sido relacionadas con la adherencia a la práctica deportiva y el rendimiento en deportistas sin discapacidad, pero existe escasa evidencia de ello en el deporte adaptado. En este estudio correlacional, exploramos el flow, la competencia percibida y la pasión armoniosa y obsesiva en deportistas con diversidad funcional de diferentes modalidades y niveles competitivos, y su influencia sobre la intención de práctica y competición futura. Se realizaron análisis de correlaciones de orden cero y análisis multivariados de regresión lineal. Los participantes informaron tener niveles moderadamente altos de flow, particularmente en la mejor competición, así como elevada competencia deportiva percibida y pasión por el deporte, particularmente pasión armoniosa. Entre las variables psicosociales y deportivas consideradas, la intención de práctica futura fue predicha por la competencia percibida, mientras que la intención de competición futura fue predicha por la pasión obsesiva y el nivel de competición. Las intervenciones dirigidas a la promoción de la participación deportiva y el incremento del rendimiento en atletas con discapacidad deben considerar estos poderosos recursos psicológicos.Esta investigación fue &nanciada en parte con la ayuda del grupo de investigación «Psicología de la Salud/Medicina Conductual» (CTS-0267) concedida por la Consejería de Economía y Conocimiento de la Junta de Andalucía (España)