University of Extremadura
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Ángel Braulio Ducasse. The third of the three from Guareña and the most forgotten
No full textÁngel Braulio Ducasse fue unos de los llamados “Tres poetas de Guareña” y el más olvidado. Al contrario que los otros dos, Luis Chamizo y Eugenio Frutos, moriría trágicamente en agosto de 1936, truncando su prolífica carrera literaria a la edad de 30 años. Muy amigo del escritor y poeta Francisco Valdés, ambos compartirían el mismo y fatídico destino.Ángel Braulio Ducasse was one of those called “Three poets from Guareña” and the most forgotten. Unlike the other two, Luis Chamizo and Eugenio Frutos, i would die tragically in August 1936, cutting short his prolific literary career at the age of 30. Very friend of the writer and poet Francisco Valdés, both would share the same fateful destiny.peerReviewe
The professionals who train people who offer themselves for adoption
No full textUn rasgo característico de la sociedad española es la diversidad familiar. Entre sus posibles modelos están las familias adoptivas, representadas en una multiplicidad de estructuras que difieren en su composición, rasgos y dinámicas. Aunque comparten aspectos comunes con otros modelos, también enfrentan desafíos específicos asociados a los adoptantes y a los adoptados (p.e., sus historias de vida y condiciones de desamparo). A pesar de ello, la mayoría de estas familias son exitosas, si bien deben abordar retos como contribuir a la sanación emocional de los hijos, ayudándoles a enfrentar posibles secuelas del abandono y a construir una identidad familiar que integre su pasado y el presente. Estos desafíos no son homogéneos y algunas familias pueden necesitar un mayor apoyo profesional a lo largo del proceso. Por tanto, es crucial que los profesionales conozcan y comprendan las necesidades de las familias adoptivas para brindarles un apoyo efectivo a sus miembros, a su entorno más cercano y a la sociedad, en general. Este trabajo explora las evaluaciones realizadas por los profesionales que aplicaron un programa de formación/reflexión para quienes se ofrecen para la adopción en las Islas Canarias (España), al inicio del proceso. El curso persigue que los participantes conozcan mejor las particularidades de la parentalidad adoptiva y que reflexionen profundamente sobre su decisión de adoptar. Se analizan las evaluaciones de 26 cursos, en los que participaron 500 personas. Los resultados recogen las recomendaciones de los profesionales para favorecer el ejercicio positivo de su labor; destacan la necesidad de poseer un amplio conocimiento sobre el proceso adoptivo, el desamparo y sus consecuencias, el ejercicio positivo de la parentalidad, etc.; así como sobre el manejo de técnicas de dinámica de grupo que impulsen la participación de los asistentes y ayuden a mantener su interés a lo largo de las sesiones.A characteristic feature of Spanish society is family diversity. Among its possible models are adoptive families, represented in a multiplicity of structures that differ in their composition, traits and dynamics. Although they share common aspects with other models, they also face specific challenges associated with adopters and adoptees (e.g., their life histories and conditions of homelessness). Despite this, most of these families are successful, although they must address challenges such as contributing to the emotional healing of the children, helping them to cope with possible sequelae of abandonment and building a family identity that integrates the past and the present. These challenges are not homogeneous and some families may need greater professional support throughout the process. Therefore, it is crucial for professionals to know and understand the needs of adoptive families in order to provide effective support to their members, their immediate environment and society in general. This paper explores the evaluations made by professionals who applied a training/reflection program for those who offer themselves for adoption in all the Canary Islands (Spain), at the beginning of the process. The aim of the course is for participants to learn more about the particularities of adoptive parenthood and to reflect deeply on their decision to adopt. The evaluations of 26 courses, in which 500 people participated, are analyzed. The results include the recommendations of the professionals to favor the positive exercise of their work. They highlight the need to have a broad knowledge of the adoptive process, homelessness and its consequences, the positive exercise of parentality, etc.; as well as the use of group dynamics techniques that encourage the participation of the participants and help to maintain their interest throughout the sessions.peerReviewe
Feasibility study of three-phase modular converter for dual-purpose application in DC and AC microgrids
No full textVersión aceptada del trabajo publicado en: IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 12, no. 2, pp. 1348-1358, April 2024, doi: 10.1109/JESTPE.2023.3247960.El concepto moderno de un convertidor universal está destinado como un convertidor de energía (PC) adecuado para su aplicación tanto en redes de corriente continua como de corriente alterna utilizando los mismos conectores externos. Esta nueva familia fue propuesta recientemente para permitir una integración más fácil de fuentes de energía renovable y sistemas de almacenamiento de energía (ESSs), interfiriendo con redes de corriente continua/corriente alterna y/o cargas con una redundancia mínima de interruptores de potencia y elementos pasivos. Se espera que este tipo de solución y aplicaciones sean una realidad en la próxima década, ya que las redes de distribución de baja tensión de corriente alterna y corriente continua coexistirán. Sin embargo, las soluciones iniciales propuestas como convertidores universales se centraron en sistemas de conversión de energía de corriente alterna monofásica. En este sentido, este artículo propone y describe un nuevo miembro de la familia de convertidores universales adecuado para la conversión de energía de corriente continua a corriente continua y de corriente continua a corriente alterna (tanto en tres fases trifásicas como en tres fases tetrafásicas). La topología de potencia propuesta se deriva como una extensión modular de la celda bidireccional única buck-boost. Se discuten sus principales modos de operación (buck y boost), y se desarrolla una técnica de modulación por ancho de pulso para generar los patrones de conmutación correspondientes. La solución propuesta se valida con éxito en modo de lazo abierto tanto en simulación como experimentalmente con un prototipo de laboratorio. La eficiencia medida del PC fue superior al 97% en el modo de corriente continua a corriente alterna y alrededor del 99% en el modo de corriente continua a corriente continua.The modern concept of a universal converter is intended as a power converter (PC) suitable for application in both dc or ac grids using the same external connectors. This novel family was recently proposed to allow easier integration of renewable energy sources and energy storage systems (ESSs), interfacing with dc/ac grids and/or loads with a minimum redundancy of power switches and passive elements. This kind of solution and applications are expected to be a reality in the nearest decade, as ac and dc low voltage distribution networks will coexist. Nevertheless, the initial solutions proposed as universal converters were focused on ac single-phase power conversion systems. In this sense, this article proposes and describes a new member of the universal converter family suitable for dc–dc and dc–ac power conversion (both in three-phase three-wire and in three-phase four-wire). The proposed power topology is derived as a modular extension from the single buck-boost bidirectional cell. Its main operation modes (buck and boost) are discussed, and a pulsewidth-modulation technique is developed to generate the corresponding switching patterns. The proposed solution is successfully validated in open-loop mode both in simulation and experimentally with a laboratory prototype. The measured efficiency of the PC was above 97% in the dc–ac mode and around 99% in the dc–dc mode.This research was funded by the Junta de Extremadura (Spain) with the project (IB20165) and the program “Ayudas Talento” (TA18003). It was also partially funded by the Estonian Research Council grant PRG675 and by the Estonian Centre of Excellence in Zero Energy and Resource Efficient Smart Buildings and Districts (ZEBE).peerReviewe
Effects of feeding with a protein liquid supplement on productivity, mortality and health of "Apis mellifera" hives in southwestern Spain
No full textFinanciación Open Access proporcionada gracias al acuerdo CRUE-CSIC con Elsevier.Colony collapse disorder (CCD) has affected bees worldwide in recent decades, with southwestern Spain being no exception. This disorder is one of the main causes of Apis mellifera mortality and is believed to be caused by environmental, social and sanitary conditions. Dietary supplementation can help to improve some parameters of the general status and sanitary condition of bees, such as infestation by certain recurrent pathogens, including Varroa destructor and Nosema ceranae, by enhancing immune and social response. Thus, the aim of this study was to test a liquid hydrolysed protein supplement on the health and general status of the hive in several apiaries with access to the same natural food and under similar climatic conditions. We selected two groups of ten hives (supplemented by either placebo or protein) from five apiaries where the number of adult bees, amount of brood (open and operculated), honey and pollen reserves, infestation by V. destructor, N. ceranae, deformed wing virus (DWV) and chronic bee paralysis virus (CBPV) were measured. Additionally, we assess the expression of four immune system-related genes and a gene encoding vitellogenin. At the end of this work, treated hives showed a significant increase in open brood and a decrease in V. destructor infestation. Also, these hives showed a significant decrease in the mortality rate after the cold season. Therefore, supplementation with this product improved the health of the hive and could be a promising tool against bee colony loss.El síndrome de despoblamiento de las colmenas ha afectado a las abejas en todo el mundo en las últimas décadas, y el suroeste de España no es una excepción. Este trastorno es una de las principales causas de mortalidad de Apis mellifera y se cree que es causado por condiciones ambientales, sociales y sanitarias. La suplementación dietética puede ayudar a mejorar algunos parámetros del estado general y la condición sanitaria de las colmenas, como la infestación por ciertos patógenos recurrentes, incluidos Varroa destructor y Nosema ceranae, al mejorar la respuesta inmune y social. Así, el objetivo de este estudio fue probar un suplemento proteico hidrolizado líquido sobre el estado sanitario y general de la colmena en varios colmenares con acceso al mismo alimento natural y en condiciones climáticas similares. Seleccionamos dos grupos de diez colmenas (complementadas con placebo o proteína) de cinco colmenares donde se midieron el número de abejas adultas, la cantidad de cría (abierta y operculada), las reservas de miel y polen, la infestación por V. destructor, N. ceranae, virus de las alas deformes (DWV) y virus de la parálisis crónica de las abejas (CBPV). Además, evaluamos la expresión de cuatro genes relacionados con el sistema inmunológico y un gen que codifica la vitelogenina. Al final de este trabajo, las colmenas tratadas mostraron un aumento significativo en la cría abierta y una disminución en la infestación por V. destructor. Además, estas colmenas mostraron una disminución significativa en la tasa de mortalidad después de la estación fría. Por tanto, la suplementación con este producto mejoró la salud de las colmenas y podría ser una herramienta prometedora contra la pérdida de colonias de abejas.This work was supported by Fondo Español de Garantía Agraria O.A. (FEGA), Ministerio de Agricultura, Pesca y Alimentación [record number O00000226e2000044811], Spain and by Agencia Estatal de Investigación, Ministerio de Ciencia e Innovación, Gobierno de España [SNEO-20222326].peerReviewe
Enseñando Historia Económica en la era de la Inteligencia Artificial: Nuevos y viejos métodos para nuevos y no tan nuevos desafíos
No full textEl libro que aquí se propone es un compendio actualizado de los derroteros por los que transita actualmente la didáctica de la Historia Económica en la Educación Superior. ¿Cómo potenciar el espíritu crítico entre estudiantes universitarios? ¿Cómo contribuir al aprendizaje autónomo? ¿Cómo ayudar a contextualizar hechos y conceptos? ¿Cómo fomentar el desarrollo de competencias digitales? ¿Cómo favorecer la capacidad de síntesis o la habilidad para comunicar ideas complejas? Más de 50 expertos procedentes de 20 universidades distintas intentan responder en este libro a tales interrogantes aportando una gran diversidad de experiencias de renovación metodológica en la enseñanza de la Historia Económica. El texto nace de las propuestas de comunicación presentadas al XV Encuentro de Didáctica de la Historia Económica (Plasencia, junio de 2024).The book proposed here is an updated compendium of the paths currently taken by the teaching of Economic History in Higher Education. How to enhance the critical spirit among university students? How to contribute to autonomous learning? How to help contextualize facts and concepts? How to promote the development of digital skills? How to promote the capacity for synthesis or the ability to communicate complex ideas? More than 50 experts from 20 different universities try to answer such questions in this book, providing a great diversity of experiences of methodological renewal in the teaching of Economic History. The text arises from the communication proposals presented to the XV Didactics of Economic History Meeting (Plasencia, June 2024).peerReviewe
A true reverse anomeric effect does exist after all: a hydrogen bonding stereocontrolling effect in 2‑Iminoaldoses
No full textThe reverse anomeric effect is usually associated with the equatorial preference of nitrogen substituents at the anomeric center. Once postulated as another anomeric effect with explanations ranging from electrostatic interactions to delocalization effects, it is now firmly considered to be essentially steric in nature. Through an extensive research on aryl imines from 2-amino-2-deoxyaldoses, spanning nearly two decades, we realized that such substances often show an anomalous anomeric behavior that cannot easily be rationalized on the basis of purely steric grounds. The apparent preference, or stabilization, of the β-anomer takes place to an extent that not only neutralizes but also overcomes the normal anomeric effect. Calculations indicate that there is no stereoelectronic effect opposing the anomeric effect, resulting from the repulsion between electron lone pairs on the imine nitrogen and the endocyclic oxygen. Such data and compelling structural evidence unravel why the exoanomeric effect is largely inhibited. We are now confident, as witnessed by 2-iminoaldoses, that elimination of the exo-anomeric effect in the α-anomer is due to the formation of an intramolecular hydrogen bond between the anomeric hydroxyl and the iminic nitrogen, thereby accounting for a true electronic effect. In addition, discrete solvation may help justify the observed preference for the β-anomer.Financial support from the Junta de Extremadura and Fondo Europeo de Desarrollo Regional (European Regional Development Fund), through grant no. GR21039, is greatly appreciatedpeerReviewe
Unlocking the Potential of Chemically Modified Carbon Gelsin Gallic Acid Adsorption
No full textThis study deals with the preparation of adsorbents from a commercial xerogel by chemically
modifying its surface with concentrated mineral acids and alkali metal chlorides, their physicochemical
characterization, and their use as adsorbents for gallic acid in aqueous solution. Although there are
publications on the use of carbon xerogels as adsorbents, we propose and study simple modifications
that can change their chemical properties and, therefore, their performance as adsorbents. The adsorbate
of choice is gallic acid and, to our knowledge, there is no history of its adsorption with carbon xerogels.
The prepared adsorbents have a high specific surface area (347–563 m2 g−1), better pore development
for samples treated with alkali metal chlorides than with mineral acids, and are more acidic than the
initial xerogel (p.z.c range 2.49–6.87 vs. 7.20). The adsorption equilibrium is reached in <16 h with
a kinetic constant between 0.018 and 0.035 h−1 for the pseudo-second-order model. The adsorption
capacity, according to the Langmuir model, reaches 62.89 to 83.33 mg g−1. The adsorption properties of
the commercial xerogel improved over a wide range of pH values and temperatures. The experimental
results indicate that the adsorption process is thermodynamically favored.This research was funded by the European Regional Development Fund and the Junta de Extremadura (grant IB20026).peerReviewe
Field-programmable analog array implementation of neuromorphic silicon neurons with fractional dynamics
No full textLas neuronas de silicio son circuitos bioinspirados con la capacidad de reproducir la modulación mediante frecuencia de pulso observada en neuronas reales. Son de particular interés en esquemas de bucle cerrado para codificar la señal de control en pulsos. Este artículo propone la realización analógica de neuronas neuromórficas de silicio con dinámica fraccionaria. En particular, el operador de orden fraccionario (FO) se introduce en las neuronas clásicas con la intención de reproducir la adaptación que se ha observado experimentalmente en neuronas reales, que es la variación en la frecuencia de disparo incluso cuando se considera un estímulo entrante constante o periódico. Para fines de validación, se realizan simulaciones utilizando una matriz analógica programable en campo (FPAA) para verificar el comportamiento de los circuitos.Silicon neurons are bioinspired circuits with the capability to reproduce the modulation through pulse-frequency observed in real neurons. They are of particular interest in closed-loop schemes to encode the control signal into pulses. This paper proposes the analog realization of neuromorphic silicon neurons with fractional dynamics. In particular, the fractional-order (FO) operator is introduced into classical neurons with the intention of reproducing the adaptation that has been observed experimentally in real neurons, which is the variation in the firing frequency even when considering a constant or periodic incoming stimulus. For validation purposes, simulations using a field-programmable analog array (FPAA) are performed to verify the behavior of the circuits.This research was funded by the Agencia Estatal de Investigación (Ministerio de Ciencia e Innovación) through the projects PID2019-111278RB-C22/AEI/10.13039/501100011033 and PID2022-141409OB-C22/AEI/10.13039/501100011033/FEDER, UE and by the European Regional Development Fund (FEDER) “A way to make Europe”. Andrés Serrano would like to thank the Ministerio de Ciencia, Innovación y Universidades for its support through the scholarship no. FPU22/00885 of the FPU Program.peerReviewe
Effects of strength traning program on physical performance in amateur female padel players
No full textEl objetivo de este estudio fue determinar los efectos de un programa de entrenamiento de fuerza explosiva en el rendimiento físico de jugadores amateur de pádel. Ocho jugadoras amateur de pádel, de entre 25 y 40 años, fueron divididas aleatoriamente en dos grupos: un grupo de control (CG, n=4) y un grupo experimental (EG, n=4). El grupo experimental llevó a cabo un programa de entrenamiento de fuerza explosiva de 6 semanas. Las variables de rendimiento físico se midieron antes y después de la intervención mediante diversas evaluaciones: Se evaluó el cambio de dirección utilizando una prueba modificada específica para el pádel (Test 505) con la aplicación "COD Timer". Los saltos horizontales bilaterales y unilaterales, junto con el salto de contramovimiento (CMJ), se midieron utilizando la aplicación "Myjump". La fuerza de las extremidades superiores se evaluó mediante lanzamiento de balón medicinal por encima de la cabeza. El grupo experimental mostró mejoras significativas en todas las variables analizadas, excepto en el salto horizontal bilateral, lo que indica una mejora general en su rendimiento después de la intervención. Estos hallazgos contribuyen a arrojar luz sobre este deporte, especialmente en el ámbito amateur, ya que la mayoría de los clubes sociales dependen de él para subsistir a pesar de la limitada información disponible.The aim of this study was to determine the effects of an explosive strength training program on the physical performance of amateur padel players. Eight females amateur padel players, aged between 25 and 40, were randomly split up in two groups: a control group (CG, n=4) and an experimental group (EG, n=4). The experimental group performed a 6-week explosive strength training program. Physical performance variables were measured before and after the intervention using several assessments: Change of direction was gauged using a modified padel-specific test (Test 505) with the "COD Timer" application. Bilateral and unilateral horizontal jumps, along with the countermovement jump (CMJ), were measured using the "Myjump" application. Upper extremity strength was evaluated through overhead medicine ball throwing. The experimental group showed significant improvements in all analyzed variables except for the bilateral horizontal jump, dis-playing an overall enhancement in their performance following the intervention. These findings contribute to shedding light on this sport, especially within the amateur domain, as most social clubs rely on it for sustenance despite the limited available information.peerReviewe
Drivers of consumer’s willingness to pay for fair trade food products: the role of positive and negative emotions
No full textThis paper proposes an explanatory model of the intention to pay for fair trade food products based on the stimulus-organism-response (S-O-R) theory. The research aims are to test the effects of general attitudes toward sustainable food products on the valuation of fair-trade food products, to study the effects of emotions on willingness to pay for fair trade food products and to analyse the mediating role of product evaluation and emotions. The proposed model was tested using an ordinary least squares estimation and an analysis combining the properties of parallel and serial mediation on a representative sample of 305 consumers in the Basque Country (Spain). Descriptive analyses indicate that respondents had a favourable attitude toward sustainable products and positively valued fair trade products. The willingness to pay was moderate. The results show the importance of emotions, especially pride, in transforming attitudes toward sustainable food products into a willingness to pay for fair trade food products. This study links the more general literature on sustainable products to that of fair-trade products, broadening the focus of the S-O-R theory. In addition, it helps fair trade organisations understand consumer behaviour influenced by positive emotions and attitudes towards sustainable products, including fair trade products.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.
The data collection in this research was supported by medicusmundi Álava/Araba and Enpresa Institutua, University of the Basque Country UPV/EHU (contract number 2020.0183).peerReviewe