University of Extremadura
Dehesa. Repositorio Institucional de la Universidad de ExtremaduraNot a member yet
24789 research outputs found
Sort by
Estudio, preparación, propiedades y aplicaciones de hormigones poliméricos de base cargas minerales y orgánicas
No full textPrograma de doctorado en Ingenierías Industriales (R024)Este trabajo se ha centrado fundamentalmente en la preparación y caracterización de hormigones poliméricos, utilizando una resina viniléster como matriz polimérica, junto con partículas o cargas minerales de pizarra y granito, así como partículas orgánicas de huesillo de aceituna y fibra de cáñamo, provenientes de canteras y plantaciones o cultivos de proximidad, respectivamente, con la intención de revalorizar tales residuos. La metodología ha consistido básicamente en la preparación de muestras con diferentes dosificaciones de los componentes, utilizando moldes abiertos de silicona donde se ha llevado a cabo la polimerización y fraguado de las muestras. Los resultados de dicho estudio tienen implicaciones de interés práctico para el estudio de la viabilidad y las dosificaciones óptimas entre los componentes para conseguir materiales de alta calidad y bajo coste. La utilización de diferentes cargas o residuos de naturaleza tanto orgánica como inorgánica, junto con el elevado número de muestras preparadas y la diversidad de técnicas experimentales de caracterización y ensayos realizados, dan cuenta del ingente volumen de trabajo que ha requerido el presente estudioThis work has focused mainly on the preparation and characterisation of polymeric concretes, using a vinylester resin as a polymeric matrix, together with mineral particles or fillers of slate and granite, as well as organic particles of olive stones and hemp fibre, from quarries and plantations or local crops, respectively, with the intention of revaluing such waste. The methodology consisted basically in the preparation of samples with different dosages of the components, using open silicone moulds where the polymerisation and setting of the samples was carried out. The results of this study have implications of practical interest for the study of the feasibility and optimal dosages between the components to achieve high quality and low cost materials. The use of different fillers or wastes of both organic and inorganic nature, together with the large number of samples prepared and the diversity of experimental characterisation techniques and tests carried out, account for the enormous volume of work required for this study
Early Intervention, Regular Education, and Family: Reciprocal Influences on Communication and Language Disorders
No full textFamilies are the primary caregivers and the main source of support for their children. Family resilience involves coping and adapting to stressful situations. This study explored the impact of previous treatment experience on parental resilience, in families, as well as the relationship between family history of communication and language disorders and parental stress. These variables were assessed through the Resilience Scale and the Parental Stress Index in parents of 220 children aged 3 to 6 years attending mainstream schools and early intervention (EI) centers in Caceres (Spain). The results revealed significant differences in resilience between parents who had received previous treatments and those who had not (p = 0.11). Furthermore, a significant association was found between having no family history of communication and language disorders and the Dysfunctional Parent– Child Interaction subscale from the Parental Stress Index (U = −2.079, p = 0.038). These findings highlight the relevance of previous experience in EI to build family resilience as resilient parents are more likely to be actively involved in their children’s education and create a supportive environment. Thus, promoting resilience in educational settings may have positive effects on children’s and families’
quality of life during the EI process.peerReviewe
Co-teaching and motivation: towards a model of emotional collaboration in the classroom
No full textLa docencia compartida (DC) es un modelo pedagógico en donde colaboran de manera conjunta dos o más profesores, con el fin de fortalecer la calidad educativa, las relaciones interpersonales y el desarrollo profesional de los docentes. Los objetivos planteados en este estudio fueron: analizar la relación entre la DC y la motivación del aprendizaje de los estudiantes, identificar diferencias significativas en la percepción de la DC según variables demográficas y examinar la percepción de la motivación del alumnado en relación con la experiencia de DC. Los participantes del estudio fueron 758 estudiantes de Educación Secundaria Obligatoria (ESO), 377 mujeres (49.7%), 351 hombres (46.3%), y 30 estudiantes (4%) que no especificaron su género. La mayoría de los estudiantes tenía entre 12 y 15 años. Se utilizó un cuestionario para medir la perspectiva de la Docencia Compartida, y la Escala de Evaluación Motivacional del Proceso de Aprendizaje. Se realizó un análisis descriptivo y correlacional. Entre los resultados más importantes se destaca que, un porcentaje significativo de estudiantes ha tenido experiencia en DC. Las mujeres y los estudiantes más jóvenes, así como los de primero y cuarto de la ESO, reportan mayor satisfacción con la docencia compartida. Las diferencias en inclusión se relacionan solo con el curso. Los estudiantes que han participado en la DC muestran niveles más altos de motivación intrínseca y extrínseca. Con lo expuesto se concluye que la DC es un modelo pedagógico eficaz para mejorar la motivación intrínseca y extrínseca, el clima escolar y el rendimiento académico de los estudiantes.Co-teaching (CT) is a pedagogical model in which two or more teachers collaborate jointly in order to strengthen educational quality, interpersonal relationships and the professional development of teachers. The objectives of this study were: to analyze the relationship between CT and student learning motivation, to identify significant differences in the perception of CT according to demographic variables, and to examine the perception of student motivation in relation to the CT experience. The study participants were 758 Compulsory Secondary Education (ESO) students, 377 females (49.7%), 351 males (46.3%), and 30 students (4%) who did not specify their gender. Most of the students were between 12 and 15 years of age. A questionnaire was used to measure the Shared Teaching perspective, and the Motivational Evaluation of the Learning Process Scale. A descriptive and correlational analysis was performed. Among the most important results, a significant percentage of students have had CT experience. Women and younger students, as well as those in the first and fourth years of ESO, report greater satisfaction with shared teaching. Differences in inclusion are related only to the course. Students who have participated in CT show higher levels of intrinsic and extrinsic motivation. With the above, we conclude that CT is an effective pedagogical model for improving intrinsic and extrinsic motivation, school climate and students’ academic performance.Esta investigación ha sido financiada por la Junta de Castilla y León según Proyecto de Investigación ORDEN EDU/322/2022, de 1 de abril, por la que se convoca la selección de proyectos de investigación educativa a desarrollar por equipos de profesores y equipos de inspectores, que presten servicios en centros docentes no universitarios sostenidos con fondos públicos o en servicios educativos de la Comunidad de Castilla y León durante los cursos 2022/2023 y 2023/2024, y se delega la competencia para su resolución. La docencia compartida y su aplicación en la ESO para la mejora de la inclusión educativa: Programa E-Co-Teach-CyLpeerReviewe
Desarrollo de herramientas orientadas al estudio de electrolizadores PEM para implementación de réplica digital
No full textPrograma de Doctorado en Ingenierías IndustrialesLa creciente escasez de los combustibles fósiles y la transición energética hacia el consumo de fuentes de energías renovables han propiciado un auge en el desarrollo de tecnologías dedicadas al aprovechamiento del hidrógeno. Para la generación de este gas, es común el uso de electrolizadores, dispositivos basados en el proceso electroquímico de electrólisis que separan un compuesto en sus componentes fundamentales. A través de este proceso se obtiene hidrógeno a partir de carburos o de elementos no contaminantes como el agua. El funcionamiento de este dispositivo resalta por su complejidad, dificultando su integración inmediata en sistemas físicos. Por ello, se requiere una comprensión previa del comportamiento de estos equipos previo a su uso e implementación. Ante esta necesidad, la presente Tesis Doctoral tiene como objetivo desarrollar herramientas orientadas al estudio de electrolizadores tipo PEM para la implementación de una réplica digital. Este conjunto de herramientas consta de: una plataforma de simulación mutli modelo con la cual realizar un estudio teórico y comparativo de diversos modelos de la literatura científica; un sistema de monitorización en tiempo real basado en el Internet de las Cosas dedicado a la visualización y estudio del funcionamiento de un electrolizador PEM integrado en una smart Microgrid; una réplica digital del electrolizador PEM físico que recrea su operación de mane ra virtual. En este documento se describe el proceso de diseño e implementación de estas herramientas, resaltando las características y funcionalidades de cada una de estas.The increasing scarcity of fossil fuels and the energy transition towards the consumption of renewable energy sources have fostered a surge in the development of technologies dedicated to harnessing hydrogen. For the generation of this gas, the common practice involves the use of electrolyzers, devices based on the electrochemical process of electrolysis that separates a compound into its fundamental components. Through this process, hydrogen is obtained from hydrocarbons or non-polluting elements such as water. The operation of this device stands out for its complexity, hindering its immediate integration into physical systems. Therefore, a prior understanding of the behavior of these devices is required before their use and implementation. In response to this need, the present Doctoral Thesis aims to develop tools focused on the study of PEM electrolyzers for the implementation of a digital replica. This set of tools consists of: a multi- model simulation platform for conducting a theoretical and comparative study of various models from scientific literature; a real-time monitoring system based on the Internet of Things, dedicated to the visualization and study of the operation of a PEM electrolyzer integrated into a smart Microgrid; a digital replica of the physical PEM electrolyzer that recreates its operation virtually. This document describes the process of designing and implementing these tools, highlighting the characteristics and functionalities of each one
Treinamento pliométrico e desempenho do salto vertical em bailarinos clássicos
No full textLa capacidad del salto es una cualidad importante en el ballet clásico. Se ha demostrado que el entrenamiento pliométrico es efectivo en muchos deportes para mejorar el salto vertical. El objetivo de este estudio fue evaluar el impacto de 8 semanas de entrenamiento pliométrico sobre la capacidad del salto vertical y petit allegros en bailarinas de ballet clásico. 9 bailarinas (22,4 ± 3,05 años; 167 ± 0,06 cm; 56,1 ± 7,66 kg.; 14,2 ± 2,11 años de experiencia) realizaron 8 semanas de entrenamiento pliométrico. Antes (pre) y después (post) del entrenamiento, se evaluó el CMJ, la altura media de 32 petit allegros, la fuerza G y la eficiencia del salto. En el CMJ y en los petit allegros mejoraron después del entrenamiento (p0,05). En conclusión, 8 semanas de entrenamiento pliométrico fueron efectivas para mejorar el CMJ en condiciones de descanso y fatiga y las habilidades específicas de danza en bailarinas de ballet clásico.Jump capacity is an important quality in classic ballet. Plyometric training has been shown effective in many sports to improve vertical jump. The aim of this study was to evaluate the impact of 8 weeks of plyometric training on vertical jump capacity and allegros jump in classic ballet dancers. 9 female classic dancers (22.4 ± 3.05 years; 167 ± 0.6 cm; 56.1 ± 7.66 kg.; 14.2 ± 2.11 years of experience) carried out 8 weeks plyometric training. Before (pre) and after (post) training, CMJ, mean 32-allegro jump height, G force and jump efficiency were evaluated. CMJ and allegro jump were improved after training (p.05). In conclusion, 8 weeks of plyometric training was effective to improve CMJ in rest and fatigue conditions and specific dance skills in ballet classic dancers.A capacidade de salto é uma qualidade importante no balé clássico. O treinamento pliométrico tem se mostrado eficaz em muitos esportes para melhorar o salto vertical. O objetivo deste estudo foi avaliar o impacto de 8 semanas de treinamento pliométrico na capacidade de salto vertical e salto allegros em bailarinos clássicos. Nove bailarinas clássicas (22,4 ± 3,05 anos; 167 ± 0,6 cm; 56,1 ± 7,66 kg.; 14,2 ± 2,11 anos de experiência) realizaram 8 semanas de treinamento pliométrico. Antes (pré) e após (pós) treinamento foram avaliados o CMJ, a altura média do salto allegro 32, a força G e a eficiência do salto. O CMJ e o salto allegro melhoraram após o treinamento (p0,05). Concluindo, 8 semanas de treinamento pliométrico foram eficazes para melhorar o CMJ nas condições de repouso e fadiga e habilidades específicas de dança em bailarinos clássicos.Palabras clave: metodología observacional; tiempo; observador.peerReviewe
Factores asociados a la violencia entre iguales y a la violencia sexual
No full textTrabajo de los Grupos de Investigación:
PSYCOUEX Y GIPESEl presente informe complementa al primer estudio donde hemos identificado y cuantificado
la violencia contra menores fuera del entorno familiar. Fundamentalmente, este segundo
estudio se centra en analizar las correlaciones entre la violencia entre iguales y violencia sexual
con el consumo temprano de alcohol, drogas, resultados académicos, estilos parentales y
problemas de salud mental. Aunque esta metodología no nos permite establecer relaciones
de causa efecto, nos puede aportar información de las motivaciones y causas de la violencia.Consejería de Salud y Servicios Sociales, a través de la Secretaría General de Servicios Sociales, Inclusión, Infancia y Familia de la Junta de Extremadur
Trabajadores mayores y digitalización: la necesidad de remontar la brecha
No full textPonencia presentada en VIII Congreso Internacional y XXI Congreso Nacional de la Asociación Española de Salud y Seguridad Social, «Igualdad de trato y no discriminación en la salud y protección social en la era de la disrupción digital». 17 y 18 de Octubre de 2024La digitalización del mundo del trabajo está teniendo repercusión en todos los segmentos del sistema de protección social: pensiones de jubilación, prestaciones por incapacidad, asistencia sanitaria… también, cómo no, sobre la atención a las personas mayores. Y en el mercado laboral de hoy, especialmente en lo que atiene a las nuevas tecnologías, hay que poner de relieve el fenómeno de la brecha digital, el cual viene influido por distintos factores, entre los que destaca la edad.Esta publicación es parte del proyecto de I+D+i del Plan Nacional 2020, “Los Sistemas de Protección Social ante la incidencia de la disrupción digital”, Referencia: PID2020-115701RB-I00, financiado por MCIN/ AEI/10.13039/50110001103
El anzuelo de la noticia: el clikbait como generador de informaciones falsas
No full textEn la actualidad, los medios de comunicación digitales se rigen por un modelo de negocio que depende esencialmente de los ingresos que reciben a partir de los anuncios publicitarios que se incluyen en su vertiente digital. En un intento desesperado por atraer a la mayor audiencia posible con el propósito de asegurar su supervivencia, los periódicos han adoptado en su versión en línea distintas estrategias, entre las que destaca el clickbait, recurso que se utiliza para crear titulares llamativos y apelativos. Al encontrarse con un encabezamiento de este tipo, el lector se ve obligado a acceder mediante el clic a la noticia completa para poder satisfacer su propia curiosidad. El presente trabajo pretende dar una definición del concepto de clickbait, así como profundizar en sus principales rasgos formales.Nowadays, digital media are regulated by a business model which essentially depends on the income they receive from the advertisements that are included in their digital version. On a desperate attempt of attracting the largest possible audience with the purpose of assuring their survival, newspapers have adopted in their online edition several strategies, among which clickbait stands out, a resource used for creating attractive and appellative headlines. When presented with a heading of these characteristics, the reader is forced to access by clicking to the complete piece of news in order to satisfy their curiosity. The present work aims to give a definition of the clickbait concept, as well as to study in more detail its main formal features.Memoria de proyecto, 46 p. (pdf)Grado en Filología Hispánica. Universidad de Extremadur
Improving the nutritional evaluation in head neck cancer patients using bioelectrical impedance analysis: Not only the phase angle matters
No full textBACKGROUND: Malnutrition and sarcopenia are highly prevalent in patients with head neck cancer (HNC). An accurate early diagnosis is necessary for starting nutritional support, as both are clearly associated with clinical outcomes and mortality. We aimed to evaluate the applicability and accuracy of body composition analysis using electrical bioimpedance vectorial analysis (BIVA) for diagnosing malnutrition and sarcopenia in patients with HNC cancer undergoing systemic treatment with chemotherapy or radiotherapy.
METHODS: Cross-sectional, observational study that included 509 HNC patients. A comprehensive nutritional evaluation that included BIVA was performed.
RESULTS: The prevalence of malnutrition was higher in patients that received treatment with chemotherapy (59.2% vs. 40.8%, P < 0.001); increased mortality was observed in malnourished patients (33.3% vs. 20.1%; P < 0.001); ECOG status (1-4) was also worse in malnourished patients (59.2% vs. 22.8% P < 0.001). Body cell mass (BCM) and fat mass were the most significantly associated parameters with malnutrition [OR 0.88 (0.84-0.93) and 0.98 (0.95-1.01), respectively]; BCM and fat free mass index (FFMI) were associated with several aspects including (1) the patient-generated subjective global assessment [OR 0.93 (0.84-0.98) and 0.86 (0.76-0.97), respectively], (2) the presence of sarcopenia [OR 0.81 (0.76-0.87) and 0.78 (0.66-0.92), respectively]. A BCM index (BCMI) < 7.8 in combination with other parameters including FFMI and BCM accurately predicted patients with malnutrition [accuracy 95% CI: 0.803 (0.763-0.839); kappa index: 0.486; AUC: 0.618 (P < 0.01)]. A BCMI cutoff of 7.6 was enough for identifying males with malnutrition (P < 0.001), while it should be combined with other parameters in females.
CONCLUSIONS: Body composition parameters determined by BIVA accurately identify patients with HNC and malnutrition. Phase angle, but other parameters including BCMI, FFMI and BCM provide significant information about nutritional status in patients with HNC.This work was funded by FRESENEIUS KABI® and Project PI23/01554 funded by Instituto de Salud Carlos III (ISCIII) and co-funded by the European Union, JR19/00050, ISCIII. The funders were not involved in the study design, collection, analysis, interpretation of data, the writing of the manuscript, or the decision to submit it for publication.peerReviewe
Detection of Aspergillus flavus in Figs by Means of Hyperspectral Images and Deep Learning Algorithms
No full textPlant diseases cause economic losses and health risks, such as aflatoxins linked to liver cancer. These toxins, produced by fungi like Aspergillus flavus in figs, are often detected late through invasive methods or visual inspection. Since Spain, particularly Extremadura, is a key fig producer, alternative detection methods are essential to preventing aflatoxins in the food chain. The aim of this research is the early detection of Aspergillus flavus fungus using non-invasive techniques with hyperspectral imaging and applying artificial intelligence techniques, in particular deep learning. The images were taken after inoculation of the microtoxin using 3 different concentrations, related to three different classes and healthy figs (healthy controls). The analysis of the hyperspectral images was performed at the pixel level. Firstly, a fully connected neural network was used to analyze the spectral signature associated with each pixel; secondly, the wavelet transform was applied to each spectral signature. The resulting images were fed to a convolutional neural network. The hyperparameters of the proposed models were adjusted based on the parameter tuning process that was performed. The results are promising, with 83% accuracy, 82.75% recall, and 83.25% F1-measure for the fully connected neural network. The high F1-measure demonstrates that the model’s performance is good. The model has a low incidence of false positives for samples that contain aflatoxin, while a higher number of false positives appears in healthy controls. Due to the presence of false negatives, this class also has a high recall. The convolutional neural network results, accuracy, recall, and F1 are 77.25%, indicating moderate model performance. Only class 3, with higher aflatoxin concentration, achieves high precision and low false positive incidence. Healthy controls exhibit a high presence of false negatives. In conclusion, we demonstrate the effectiveness of pixel-level analysis in identifying the presence of the fungus and the viability of the non-invasive techniques applied in improving food safety. Although further research is needed, in this study, the fully connected neural network model shows good performance with lower energy consumption.J.D.Á., F.C.d.l.O. and J.V.C. are supported by the Spanish Ministry of Science and Innovation under projects PID2023-147409NB-C22 and PID2020-115570GB-C21, funded by MCIN/AEI/ 10.13039/501100011033 and Junta de Extremadura, project GR15068. F.C.d.l.O. is also supported by the development and innovation project PID2020-117392RR-C41, funded by MCIN/AEI/10.13039/ 501100011033 and by “ERDF A way of making Europe”, and the AGROS2022 project.peerReviewe