University of Extremadura
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Near infrared spectroscopy (NIRS) as a tool to guarantee traceability and quality control for tench
No full textInformación suplementaria en https://doi.org/10.12706/itea.2023.014La composición nutricional de la dieta afecta directamente a la calidad final de la carne de tenca (Tinca tinca L.). Así, en los últimos años se ha apostado por sustituir el componente proteico de los piensos por alternativas vegetales más sostenibles. El diseño experimental del cual deriva este estudio consistió en sustituciones de harina de pescado ecológica por diferentes porcentajes de harina de soja ecológica y harina de soja pregerminada. Por tanto, el objetivo fue evaluar la capacidad de la tecnología espectroscópica de reflectancia en el infrarrojo cercano (NIRS) por reflectancia para la clasificación de la carne de tenca de acuerdo al tipo de dieta empleada y la cuantificación de los principales parámetros nutricionales. Se utilizaron diferentes pre-tratamientos espectrales previo a las regresiones por mínimos cuadrados parciales para predicciones cualitativas (PLS-DA) y cuantitativas (PLSR). El mejor modelo PLS-DA mostró una precisión para la clasificación del 97,5 % en validación cruzada; mientras que el mejor modelo PLSR mostró una buena capacidad predictiva para la materia seca (g/100 g), grasa (g/100 g Materia seca), y γ-tocoferol (mg/g materia seca) (0,689 ≤ R2vc ≤ 0,804), sugiriendo la posibilidad de realizar un control rápido e in situ de la trazabilidad y calidad de la carne de tenca mediante la tecnología NIRS.The nutritional composition of the diet directly affects the final quality of tench meat (Tinca tinca L.). Thus, in recent years there has been a commitment to replace the protein component of feed with more sustainable vegetable alternatives. The experimental design from which this study is derived consisted of substituting organic fish meal with different percentages of organic soybean meal and pregerminated
soybean meal. Therefore, the objective of this study was to evaluate the potential of Near infrared spec troscopy (NIRS) in categorizing tench according to the feed they received during its fattening phase and the quantification of the main nutritional parameters. Different spectral pretreatments were used pre vious to the partial least squares regressions for qualitative (PLS-DA) and quantitative (PLSR) predictions. The best PLS-DA model showed an accuracy for classification of 97.5 % in cross-validation; while the best PLSR model showed a good predictive capacity for dry matter (g/100 g), fat (g/100 g Dry Matter), and γ-tocopherol (mg/g dry matter) (0.689 ≤ R2vc ≤ 0.804), suggesting the possibility of performing a rapid and in situ control of the traceability and quality of tench meat by means of NIRS technology.Este estudio fue financiado por el programa PLEAMAR de la Fundación Biodiversidad “Gestión Sostenible de la Acuicultura Ecológica: Optimización de las estrategias de alimentación en la producción ecológica de tencas”.peerReviewe
Low-Voltage CMOS Capacitor-Less LDOs: Bulk-Driven Versus Gate-Driven Comparative Study
No full textThis paper explores the feasibility of a capacitor-less (CL) low-dropout (LDO) regulator to operate efficiently in a low voltage environment. The CL-LDO scheme selected is based on a unity-gain feedback configuration around the error amplifier (EA), so that the inclusion of high-value on-chip resistors is avoided and different key parameters, such as the power supply rejection or the noise, are optimized. A comparative analysis has been carried out over the same LDO structure including a bulk-driven and a gate-driven EA, respectively. The pass branch of the voltage regulator is provided with pseudo-class- AB operation, in order to lead to a very small quiescent current in the standby operation mode, whereas a very large current can be delivered to the load when required. Both regulators were designed and fabricated in 180 nm CMOS technology to operate with a maximum supply voltage of 1.8 V. The extensive experimental characterization showed that the bulk-driven LDO can achieve a significantly lower minimum supply voltage, i.e., 0.6 V, as compared to the gate-driven counterpart, 1 V, under the same reference voltage and load current conditions.This work was supported in part by the MCIN/AEI/10.13039/501100011033 and FEDER and European Union NextGenerationEU/PRTR under Project PID2021- 128009OB-C32 and Project TED2021-132372B-I00; in part by the European Regional Development Fund: Xunta de Galicia-Consellería de Cultura, Educación e Ordenación Universitaria Accreditation 2019–2022, under Grant ED431G-2019/04; and in part by the Reference Competitive Group Accreditation 2021–2024, under Grant GRC2021/48.peerReviewe
Evaluation of temporal stability of management zones (MZ) in permanent pastures
No full textPrecision agriculture (PA) intents to validate technological tools that capture soil and crop spatial variability, which constitute the basis for the establishment of differentiated management zones (MZ). Soil apparent electrical conductivity (ECa) sensors are commonly used to survey soil spatial variability. Temporal stability of the surveys is essential to ensure correct medium and long-term decisions. In this study, an ECa contact-type sensor (Veris 2000 XA) and an electromagnetic induction sensor (EM-38) were used in four fields of dryland pastures in Alentejo region of Portugal. The first survey was carried out in October 2018 and the second was carried out in September 2020. The aim of this study was to assess the temporal stability of ECa patterns using different types of sensors. Data processing involved synchronizing geographic coordinates obtained by the two types of ECa sensors in each location and establishing MZ based on geostatistical analysis of altimetry and ECa data. Although the basic technologies have different principles (contact versus non-contact sensors), the surveys were carried out at different soil moisture conditions and were temporarily separated (about 2 years), ECa measurements showed statistically significant correlation in all experimental fields, which was reflected in spatially stable patterns of the MZ maps. These results provide perspectives for future developments, which will need to occur in the creation of algorithms that allow validating the spatial variability and temporal stability of ECa through smart soil sampling and analysis to allow recommendations for sustained soil amendment or fertilization.A Agricultura de Precisão (AP) procura validar ferramentas tecnológicas que permitan captar a variabilidade espacial das culturas e do solo, o que constitui a base para o estabelecimento de zonas homogéneas de gestão (ZHG). Os sensores que medem a condutividade elétrica aparente do solo (CEa) são exemplo destas ferramentas no levantamento da variabilidade espacial das caraterísticas do solo. A estabilidade temporal dos padrões de variabilidade espacial da CEa é essencial para assegurar corretas decisões a médio e longo prazo. Neste estudo, foram usados dois sensores de CEa, um sensor de contacto (Veris 2000 XA) e um sensor de indução eletromagnética (EM-38), em quatro parcelas de pastagens permanentes de sequeiro no Alentejo. O levantamento com o sensor de contacto foi realizado em outubro de 2018 e o levantamento com o sensor de indução foi realizado em setembro de 2020. Este estudo teve como objetivo avaliar a estabilidade temporal dos padrões das ZHG resultantes de medições da CEa com diferentes sensores em diferentes datas. O processamento de dados incluiu a sincronização das coordenadas geográficas obtidas pelos dois sensores em cada parcela e o estabelecimento de ZHG a partir de análise geoestatística, tanto da CEa como da altimetria. Apesar das condições do solo serem diferentes, nomeadamente em termos de humidade, e dos sensores terem uma forma diferente de medição (de contacto versus não contacto), os valores da CEa mostraram correlações estatisticamente significativas em todos os campos experimentais, o que se refletiu na estabilidade dos padrões espaciais das ZHG obtidas. Estes resultados abrem boas perspetivas para futuros desenvolvimentos, os quais deverão ocorrer ao nível dos algoritmos que permitam a validação da variabilidade espacial e da estabilidade temporal da CEa através de amostragem inteligente do solo, conduzindo a recomendações sustentadas ao nível da fertilização ou da correção do solo.Este trabalho foi suportado por fundos Nacionais através da Fundação para a Ciência e a Tecnología (FCT) – Projeto IIDB/05183/2020.peerReviewe
¿El entrenamiento de la inteligencia emocional genera diferencias en la autorregulación emocional? Un estudio cuasi-experimental en educación secundaria
No full textLa autorregulación emocional (AR-E) se considera una habilidad fundamental para el bienestar personal e interpersonal, especialmente para los desafíos de los jóvenes en la actualidad, como las redes sociales, los problemas de salud mental o el aumento de los conflictos entre compañeros. Sin embargo, la autorregulación no se desarrolla de forma natural y requiere un esfuerzo consciente a través de experiencias frecuentes para ser adquirida. El presente estudio tiene como objetivo analizar los efectos de un programa de formación en inteligencia emocional sobre la AR-E de estudiantes de educación secundaria y conductas conflictivas. Para ello, hemos utilizado la metodología del Aprendizaje-Servicio (ApS) con estudiantes del grado de Psicología aplicando los contenidos del programa INTEMO (Aranda et al., 2013) basados en el entrenamiento de habilidades emocionales. La muestra está formada por 87 alumnos de 2oESO de un centro de secundaria de Salamanca (España). Para medir el impacto del programa, hemos evaluado las habilidades emocionales a través de los ítems autoinformados del programa INTEMO y algunas de las situaciones de resolución de problemas emocionales de la adaptación española del MSCEIT (Mayer et al., 2023). Los resultados no muestran diferencias entre los grupos ni a lo largo del tiempo. Estos se discuten brevemente.Emotional self-regulation (E-SR) is considered as a core skill for personal and interpersonal wellbeing, especially for current youths’ challenges such as social media, mental health issues, or increasing peer conflicts. Nevertheless, self-regulation is not naturally developed and requires a conscious effort through frequent experiences to be acquired. The present study aims to analyze the effects of a training program in emotional intelligence on secondary education students E-SR and conflicting behavior. To this aim, we used the Service-Learning (SL) methodology with Psychology degree students to apply the content of the INTEMO program (Aranda et al., 2013) based on training emotional skills. The sample consists of 87 students in 8th grade from a secondary education center in Salamanca (Spain). To measure the program impact, we assessed emotional skills through the INTEMO program self-reported items and part of the emotional problem-solving situations from the Spanish adaptation of the MSCEIT (Mayer et al., 2023). The results show no differences between groups or across time. They are briefly discussed.This research project was supported by the Social Affairs Service unit of Service-Learning at the University
of Salamanca, through the 2023-2024 call for projectspeerReviewe
Accessible operators on ultraproducts of Banach spaces
No full textWe address a question by Henry Towsner about the possibility of representing linear operators between ultraproducts of Banach spaces by means of ultraproducts of nonlinear maps. We provide a bridge between these “accessible" operators and the theory of twisted sums through the so-called quasilinear maps. Thus, for many pairs of Banach spaces X and Y, there is an “accessible" operator X → Y that is not the ultraproduct of a family of operators X → Y if and only if there is a short exact sequence of quasi-Banach spaces and operators 0 → Y → Z → X → 0 that does not split. We then adapt classical work by Ribe and Kalton-Peck to exhibit pretty concrete examples of accessible functionals and endomorphisms for the sequence spaces ₚ. The paper is organized so that the main ideas are accessible to readers working on ultraproducts and requires only a rustic knowledge of Banach space theory.Partially supported by PID2019-103961GB-C21 and Junta de Extremadura IB20038.peerReviewe
The fight against the infringement of intellectual property rights from an administrative perspective: institutional enforcement measures in the European Union and Spain
No full textLos derechos de propiedad industrial e intelectual necesitan mecanismos adecuados para su indemnidad y salvaguarda frente a sus vulneraciones, entre las que destacan los fenómenos de la piratería y la falsificación, graves problemas públicos con diferentes aristas. Se analizan en este artículo dos ejemplos de las denominadas como “actuaciones institucionales de observancia” de estos derechos, a escala de la Unión Europea (el Observatorio Europeo de la EUIPO) y en el ámbito nacional (la Comisión Intersectorial).Intellectual Property Rights require the provision of adequate mechanisms for their indemnity against infringements. Among them, the phenomena of piracy and counterfeiting are considered as serious multi-faceted policy problems. In this essay, two examples of the so-called “institutional enforcement measures” for IP rights are analyzed, both UE-wide (the Observatory of the EUIPO) and in the case of Spain (the Intersectoral Commission).peerReviewe
Speech and Narrative Setting in Herodian’s History: The Battle Exhortation of Maximinus Thrax (Hdn. 7.8.4-8)
No full textEl objetivo de este artículo es estudiar una de las partes más importantes de la Historia de Herodiano: los discursos y su engarce narrativo. Para alcanzar este objetivo, tras pasar revista a una serie de pasajes de tipo metodológico que aportan luz sobre el papel de los discursos y de la retórica en la obra, analizaremos una de las arengas más significativas, la pronunciada por el emperador Maximino Tracio (Hdn. 7.8.4-8). El análisis demuestra que los discursos de Herodiano no han sido concebidos como ejercicios retóricos destinados a poner de manifiesto su formación oratoria o a rivalizar con sus antecesores, sino que están claramente subordinados a la narración de los hechos y que los engarces narrativos son decisivos en esta tarea.The aim of this paper is to study how one of the most important parts of Herodian’s History has been elaborated: the speeches and their narrative setting. To achieve this goal, after reviewing some methodological passages in Herodianus’ work that shed light on the role of speeches and rhetoric in his work, we will analyse one of the most significant speeches, the battle exhortation delivered by the emperor Maximinus Thrax (Hdn. 7.8.4-8). The analysis shows that Herodian’s speeches were not conceived as rhetorical exercises designed to demonstrate his oratorical training or to compete with his predecessors, but they are clearly subordinated to the narration of events and that the narrative settings are decisive in this process.El presente trabajo se enmarca en el proyecto de investigación PID2021-123069NB-100 financiado por MCIN/AEI/10.13039/501100011033 y por ERDF, A way of making Europe: «El engarce narrativo en la historiografía desde la Antigüedad hasta el Renacimiento» y en el Grupo de Investigación «Arenga» (HUM-023) de la Junta de Extremadura.peerReviewe
Impact of narrative video games on the perception of cultural heritage: a qualitative analysis of Assassin's Creed among university students
No full textEste trabajo se deriva de la tesis doctoral “Los videojuegos como recurso educativo para la enseñanza del patrimonio cultural”, financiada con una beca FPU del Ministerio de Universidades con referencia FPU20/00281La investigación sobre la interacción de los estudiantes con videojuegos educativos que integran elementos del patrimonio cultural sigue siendo limitada. Generalmente, los estudios se centran en la mediación de los educadores en esta interacción o en el análisis directo de los juegos. Esto ha generado un vacío en nuestra comprensión de los significados que los estudiantes desarrollan por sí mismos al jugar estos videojuegos. Este estudio, basado en entrevistas cualitativas, examina la franquicia de videojuegos Assassin's Creed, que recrea diversos periodos históricos y culturas a través de narrativas y escenarios detallados. Los participantes indicaron que el juego les ofrecía una perspectiva inmersiva del patrimonio cultural, diferente a la experiencia educativa tradicional en las aulas. Manifestaron una conexión personal con los personajes no jugables (NPCs) y adquirieron una comprensión más detallada y realista de las diversas perspectivas en estos entornos naturales, culturales y sociales. Además, estaban dispuestos a dejar que sus percepciones del patrimonio cultural fueran moldeadas por el juego y reflexionaron sobre las implicaciones éticas y sociales de la representación del patrimonio en los medios digitales. Sin embargo, mostraron una tendencia a pasar por alto las oportunidades para un análisis más crítico y profundo de estas experiencias digitales. Esto señala la necesidad de explorar estrategias para fomentar un enfoque crítico en el estudio de las experiencias de juego y resalta la importancia de fortalecer la conexión humana con el patrimonio en la educación patrimonial.Research on the interaction of students with educational video games that integrate elements of cultural heritage remains limited. Generally, studies focus on the mediation of educators in this interaction or on the direct analysis of the games. This has created a gap in our understanding of the meanings that students develop on their own while playing these video games. This study, based on qualitative interviews, examines the video game franchise Assassin's Creed, which recreates various historical periods and cultures through detailed narratives and settings. Participants indicated that the game offered them an immersive perspective on cultural heritage, different from the traditional educational experience in classrooms. They expressed a personal connection with non-playable characters (NPCs) and gained a more detailed and realistic understanding of the diverse perspectives in these natural, cultural, and social environments. Furthermore, they were willing to let their perceptions of cultural heritage be shaped by the game and reflected on the ethical and social implications of heritage representation in digital media. However, they showed a tendency to overlook opportunities for a more critical and in-depth analysis of these digital experiences. This highlights the need to explore strategies to foster a critical approach in the study of gaming experiences and underscores the importance of strengthening the human connection with heritage in heritage education.peerReviewe
Conceptualization and Potential of Agritourism in Extremadura (Spain) from the Perspective of Tourism Demand
No full textThe current literature considers agritourism as a valid option for promoting the development of rural areas. This would be achieved by increasing agricultural incomes. However, numerous scientific studies have revealed the difficulty in reaching a consensus on the very concept of agritourism. In addition, the definition of agritourism is rarely related to the opinion of the demand. For this reason, this research aimed to understand the idea that tourists have about this variety. To this end, more than 500 surveys were carried out, from which the tourists’ conception of agritourism and the activities it entails were deduced. Other questions were also analyzed to determine whether the conception varies between those who have already performed this type of activity and those who have not yet had the opportunity to do so. From this, we can deduct the interest that visitors have in agritourism products, evidencing their potential. This interest is deduced through the visualization of different landscapes and activities of interest to tourists. Under these four central points, the aim was to understand the aims of agritourism in Extremadura (Spain). At the methodological level, a combination of descriptive statistics and spatial statistics was used, highlighting the use of cluster analysis. The results show a significant lack of knowledge of the meaning of agritourism, especially among those who have never practiced it, and of the activities associated with it. At the same time, the selection of landscapes preferred by tourists makes it possible to establish areas with potential for the development of these activities. Likewise, knowing which activities are of interest to tourists also helps to generate complementary activities and to better target the design of agrotourism products.This study is part of the research conducted during the execution of the project “Agritourism in the dehesas of Extremadura: an opportunity to increase agricultural incomes and the fixation of the population in rural areas”, and its code number is IB20012. This research was funded by the Consejería de Economía, Ciencia y Agenda Digital de la Junta de Extremadura (the branch of the regional government that covers Economy, Science and Digital Agenda of the Regional Government of Extremadura) and by the European Regional Development Fund (ERDF).peerReviewe
Bionanocomposites preparation by design: Planning based on the modification of ceria nanoparticles by polydopamine interleaved with the chitosan biopolymer
No full textHerein, the marine source polymer, chitosan (CS), was utilized to fabricate bionanocomposites by musselinspired sonochemical assisted method. The surface modified nanofillers as active ingredients were provided by assembling biomimetic polydopamine (PDA) onto the CeO2 nanoparticles through redox polymerization as a surface modification technology. Standard spectroscopic methods were used to characterize the resulting cerium oxide PDA-treated nanoparticles (NPs). CeO2/PDA/CS nanocomposites (NC)s were manufactured using a sonochemical process by inserting nanostructured fillers into the CS polymer matrix. The morphological features and structural characteristics of NCs were considered using field emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, and thermogravimetric analysis techniques. It was found that based on the biomimetic PDA layer the hydrogen bond interactions between CS biopolymer functional units with PDA functional units have occurred. Therefore, a pleasant distribution of surface adapted NPs in macromolecular matrix in the form of nanostructured composites was observed.The authors acknowledge the University of Bonab, Bonab, Iran, and the Universidad de Extremadura, Badajoz, Spain, for partial support of this work.peerReviewe