University of Extremadura
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Fin Whale Balaenoptera physalus Historical Sightings and Strandings, Ship Strikes, Breeding Areas and Other Threats in the Mediterranean Sea: A Review (1624–2023)
No full textA review of the last 399 years (1624–2023) on fin whales (Balaenoptera physalus) in the Med- iterranean Sea was conducted, based on an extensive compilation of records published in the scien- tific literature, technical reports, public databases, journals, and social media. A total of 10,716 sight- ings and 575 mortality events have been computed, analysed by semesters and mapped in order to compare the summer–winter seasons especially and their implications on migration–residence. Vis- ual and acoustic detections, feedings, migrations, primary production areas (chlorophyll), threats and causes of death and their relations have been addressed, and a mini-review on heavy metals and pollutants has been carried out on fin whales in the Mediterranean Sea. Mortality events were most frequent between November and April, coinciding with the decreased sighting period. Ship strikes posed the greatest threat, peaking between May and October, when marine traffic tends to increase in the Mediterranean Sea. Two populations coexist in the Mediterranean Sea, one resident and the other migratory, the latter using the Strait of Gibraltar for its biannual movements. Two areas with a presence of calves (up to 7 m in length) between October and February were detected: one scattered in the northern Mediterranean and the Strait of Gibraltar and its surroundings. A crit- ical zone for collisions has been established according to the results for fin whales in the Mediterra- nean Sea.peerReviewe
Exploring invisibility in the urban cultural landscape: didactic intervention in the initial training of teachers
No full textEl paisaje cultural urbano emerge como un elemento de especial relevancia para abordar problemas socialmente relevantes. Integra diversos elementos que visibilizan y conmemoran a determinados personajes, lugares o acontecimientos históricos, en detrimento de otros colectivos o minorías, cuya representación en los símbolos del paisaje urbano resulta prácticamente inexistente. Con base en este planteamiento, este trabajo presenta los resultados de una intervención didáctica, orientada a valorar el patrimonio urbano y sus implicaciones sociales. La actividad formativa se desarrolla en la Escola Superior de Educação de Lisboa (ESELx), involucrando a dos grupos de estudiantes. El principal objetivo fue evaluar si la toponimia del callejero y las esculturas de determinados barrios de Lisboa reflejan la diversidad existente en la ciudad en términos de clases sociales, culturas y géneros. Asimismo, se exploraron las percepciones de los estudiantes en relación con el patrimonio urbano analizado. Para ello, se generaron debates, se evaluó el contenido de las producciones del alumnado y se implementó un cuestionario. Los principales resultados manifiestan que los diversos elementos del patrimonio urbano no reflejan la diversidad existente en la ciudad de Lisboa. Se evidencia una escasa representación de las figuras femeninas, así como de elementos relativos a creencias o culturas diversas y de miembros pertenecientes estratos sociales desfavorecidos. Además, se manifiesta el potencial de utilizar el patrimonio urbano como recurso didáctico para desarrollar el pensamiento crítico de los futuros educadores.The urban cultural landscape emerges as an element of spatial relevance to address socially relevant problems. It integrates various elements that make visible and commemorate certain historical figures, places or events, to the detriment of other groups or minorities, whose representation in the symbols of the urban landscape is practically non-existent. Based on this approach, this works presents the results of a didactic intervention, aimed at valuing urban heritage and its social implications. The training activity takes place at the Escola Superior de Educação de Lisboa (ESELx), involving two groups of students. The main objective was to evaluate whether the toponymy of the street map and the sculptures of certain neighborhoods in Lisbon reflect the diversity that exists in the city in terms of social classes, cultures and genders. Likewise, student perceptions in relation to the analyzed urban heritage were explored. For this purpose, debates were generated, the content of the student productions was evaluated and a questionnaire was implemented. The main results show that the various elements of the urban heritage do not reflect the existing diversity in the city of Lisbon. A scant representation of female figures is evident, as well as elements related to diverse beliefs or cultures and members belonging to disadvantaged social strata. Furthermore, the potential of using urban heritage as a teaching resource to develop the critical thinking of future educators is manifested.peerReviewe
Álgebra conmutativa (grado matemáticas).
No full textEl presente manual es la 2ª edición del primero publicado en 2019 por el Servicio de Publicaciones de la UEx. Esta obra está concebida por el autor como el manual de la asignatura cuatrimestral Álgebra Conmutativa, del segundo curso del Grado en Matemáticas de la UEx.
Este manual Introduce al estudiante en las estructuras básicas del Álgebra como las de grupo, anillo y módulo, herramientas fundamentales como el cociente de un grupo por un subgrupo, cociente de un anillo por un ideal, cociente de un módulo por un submódulo y la localización de un anillo o un módulo por un sistema multiplicativo.
Se estudian también los dominios de factorización única, cuyos ejemplos fundamentales son el anillo de los números enteros y los anillos de polinomios. Introducimos la teoría del exceso para la separación de las raíces reales y complejas de los polinomios con coeficientes complejos. Clasificamos los módulos sobre dominios de ideales principales y en particular obtenemos la clasificación de los grupos abelianos y la clasificación de los endomorfismos de un espacio vectorial.
El manual está divido en cinco temas. En cada tema incluye un cuestionario, una lista de problemas (con sus soluciones) y la biografía de un matemático relevante (en inglés).This manual is the 2nd edition of the first published in 2019 by the UEx Publications Service. This work is conceived by the author as the manual for the four-monthly subject Commutative Algebra, of the second year of the Degree in Mathematics at the UEx.
This manual introduces the student to the basic structures of Algebra such as group, ring and module, fundamental tools such as the quotient of a group by a subgroup, quotient of a ring by an ideal, quotient of a module by a submodule and localization. of a ring or a module by a multiplicative system.
Single factorization domains are also studied, the fundamental examples of which are the ring of integers and the rings of polynomials. We introduce the theory of excess for the separation of real and complex roots of polynomials with complex coefficients. We classify the modules on domains of principal ideals and in particular we obtain the classification of the abelian groups and the classification of the endomorphisms of a vector space.
The manual is divided into five topics. Each topic includes a questionnaire, a list of problems (with their solutions) and the biography of a relevant mathematician (in English).peerReviewe
Study of various mechanical properties of maize (“Zea mays”) as influenced by moisture content
No full textThe mechanical properties of agricultural materials influence not only the loads occurring inside agricultural silos, but also the design of several types of post-harvest machinery. The loads generated by these materials inside silos can be predicted with silo calculation methodologies from their mechanical properties. It has been known for many years that these properties are highly dependent on the moisture content of the material. However, to date, there are not many studies focused on its determination. The goal of this research is the determination of the internal friction angle, apparent cohesion, angle of dilatancy and apparent specific weight of maize when different moisture contents are applied. The equipment used for this study consisted mainly of direct shear and oedometer assay apparatus. The maize samples used were moistened using a climatic chamber. Moisture contents applied to maize samples ranged from 9.3% to 17.4%. Results similar to those provided by other authors were obtained for the internal friction angle, apparent cohesion and apparent specific weight. On the other hand, the values obtained for the dilatancy angle of maize as a function of moisture content could not be compared because nothing has been published so far. The values obtained for this parameter overlap with those published for this material under ambient conditions. In addition, for the samples tested, these results did not allow confirming the existence of a direct relationship between the dilatancy angle and the moisture content. Finally, the increase in moisture content led to an increase in apparent specific weight, which differed from that published in the literature. The values provided here can be used for the optimization of storage and handling structures for granular agricultural materials.This research and APC were funded by the Spanish “Agencia Estatal de Investigación” via the research project “Study of the structural behavior of corrugated wall silos using Discrete Element Models (SILODEM)”, grant number PID2019-107051GB-I00/AEI/10.13039/501100011033.peerReviewe
Spatial analysis of remote sensing and meteorological indices in a drought event in southwestern Spain
No full textWe acknowledge Euro-CORDEX for the downloadable data in the viewer developed in the framework of the PNACC and the LIFE SHARA project “Awareness and Knowledge for Climate Change Adaptation.”
We are also grateful for the rest of the free open data used in this study and their corresponding issuing agencies.Los efectos del calentamiento global y del cambio climático se están dejando sentir a través de periodos de sequía más extremos y prolongados. Para medir la sequía se utilizan múltiples índices meteorológicos, pero éstos requieren datos hidrometeorológicos; sin embargo, otros índices medidos por teledetección y utilizados para cuantificar el vigor de la vegetación pueden correlacionarse con los primeros. En este estudio se investigó la correlación entre ambos tipos de índices según el tipo de vegetación y la estación del año. Las correlaciones también se modelizaron espacialmente en un evento de sequía en el suroeste de España. Además, se compararon tres mapas con diferentes niveles de detalle en cuanto a la categorización de la vegetación. En general, los resultados mostraron que los pastizales eran la categoría mejor correlacionada entre el SPEI y el FAPAR, el LAI y el NDVI. Esta correlación fue más pronunciada en otoño y primavera, que es cuando se producen la mayoría de los cambios en la senescencia y el crecimiento de la vegetación. El análisis espaciotemporal indicó un comportamiento muy similar para los pastizales agrupados en una zona indicada por los mapas de adaptación al cambio climático como de alta evapotranspiración prevista. Por último, en un análisis de previsión basado en los bosques, los índices que mejor explicaron el rendimiento del SPEI fueron de nuevo FAPAR, LAI y NDVI, con un desfase de hasta 20 días. Por lo tanto, los resultados mostraron que los índices obtenidos por teledetección son buenos indicadores del estado de sequía y pueden explicar de forma variable los indicadores de sequía tradicionales. Además, complementar el estudio con análisis espaciotemporales permitió detectar zonas especialmente vulnerables al cambio climático.The effects of global warming and climate change are being felt through more extreme and prolonged periods of drought. Multiple meteorological indices are used to measure drought, but they require hydrometeorological data; however, other indices measured by remote sensing and used to quantify vegetation vigor can be correlated with the former. This study investigated the correlation between both index types by vegetation type and season. The correlations were also spatially modeled in a drought event in southwestern Spain. In addition, three maps with different levels of detail in terms of vegetation categorization were compared. The results generally showed that grassland was the most well correlated category between the SPEI and the FAPAR, LAI, and NDVI. This correlation was more pronounced in autumn and spring, which is when most changes in vegetation senescence and growth occur. The spatiotemporal analysis indicated a very similar behavior for grasslands grouped in an area indicated by the climate change adaptation maps as having a high evapotranspiration forecast. Finally, in a forest-based forecast analysis, the indices that best explained the performance of the SPEI were again FAPAR, LAI, and NDVI, with a lag of up to 20 days. Therefore, the results showed that remotely sensed indices are good indicators of drought status and can be variably explanatory of traditional drought indicators. Moreover, omplementing the study with spatiotemporal analysis made it possible to detect areas particularly vulnerable to climate change.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was funded by the Earth Observation Data Centre for Water Resources Monitoring (OpenEO Platform Research Grants 2022–2022/00483/001).peerReviewe
Determining the impact of education and socioeconomic status on linguistic choices in the corpus of Irish English correspondence
No full textThis chapter explores the idea introduced in Nevalainen and Raumolin-Brunberg (2003/2017, vi) that uncovering historical linguistic change in legacy texts from earlier periods of English relies on the retrieval of accurate metadata and an approach to them that is informed by a wide array of different fields of scholarship. Of particular concern is applying this orientation to achieve a deeper understanding of the interplay between linguistic choices and social status in the Corpus of Irish English Correspondence (CORIECOR). The latter is an open access “big data” digital corpus consisting of letters pertaining to Ireland composed between the 17th and early 20th centuries. The CORIECOR Visualized project has permitted us to enhance the dataset such that queries with respect to specific social characteristics of the writers that are potentially pertinent to charting the progress of linguistic changes over geographical, social, and temporal space can be automatically quantified and visualized.peerReviewe
Circulating serotonin and dopamine concentrations in osteoarthritis patients: a pilot study on the effect of pelotherapy
No full textOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer NatureBalneotherapy has demonstrated clinical efficacy in the management of pathologies involving low-grade inflammation and stress. In rheumatic conditions such as osteoarthritis (OA), this therapy presents anti-inflammatory properties and potential to improve psychological well-being. Although the neurohormones serotonin and dopamine are known to be involved in these processes, surprisingly they have not been studied in this context. The objective was to evaluate the effect of a cycle of balneotherapy with peloids (pelotherapy) on circulating serotonin and dopamine concentrations in a group of aged individuals with OA, after comparing their basal state to that of an age-matched control group. In our pilot study, a pelotherapy program (10 days) was carried out in a group of 16 elderly patients with OA, evaluating its effects on circulating serotonin and dopamine concentrations (measured by ELISA). Individuals with OA showed higher levels of serotonin and lower dopamine levels, in line with the inflammatory roles of these mediators. After pelotherapy, serotonin concentrations significantly decreased, potentially contributing to the previously reported anti-inflammatory effects of balneotherapy.This study was partially supported by the Gobierno de Extremadura-Fondo Europeo de Desarrollo Regional, Spain (GR21079).peerReviewe
The Caixa Econômica of Camps CaseBooks: Saving Practices in Campos dos Goytacazes (1878-1887)
No full textEste artigo analisa as práticas de poupança entre as classes menos abastadas durante o século XIX. Homens e mulheres pobres, livres, menores ou escravos poderiam realizar depósitos nas caixas econômicas de iniciativa privada da década de 1830. Esta análise centra-se nas práticas de poupança na Caixa Econômica de Campos entre 1878 e 1887, através dos anúncios de perdas de caderneta. São trabalhadas a historiografia das caixas econômicas privadas, assim como a presença de bancos e da escravidão em Campos dos Goytacazes. Os ideais por trás da criação da Caixa Econômica de Campos são analisados, junto com os seus estatutos. Ao constatar evidências de mulheres, menores e escravos poupadores desta instituição, este trabalho enfatiza tanto a relação entre a escravidão e instituições financeiras, sob a ótica das práticas de poupança bancária por escravos no Império do Brasil, quanto a maior presença das mulheres com poupança do que os homens.This article analyzes savings practices among the less well-off classes during the 19th century. Poor men and women, free, minors, or slaves could make deposits in private savings banks in the 1830s. This analysis focuses on savings practices at the Caixa Econômica de Campos between 1878 and 1887, through the announcements of passbook losses. The historiography of private savings banks is discussed, as well as the presence of banks and slavery in Campos dos Goytacazes. The ideals behind the creation of the Caixa Econômica de Campos are analyzed, along with its statutes. By finding evidence of women, minors, and slaves saving in this institution, this work emphasizes both the relationship between slavery and financial institutions, from the perspective of bank savings practices by slaves in the Empire of Brazil, and the greater presence of women with than men among the savers.peerReviewe
Modern learning paradigms: A bibliometric analysis of augmented reality and virtual reality in vocational education
No full textThis bibliometric analysis aimed to explore the publication trends of the last decade, especially on modern learning paradigms, focusing on implementing Augmented Reality and Virtual Reality in vocational education. This research specifically addressed the analysis of current technology trends, gaps, challenges, strengths, and opportunities of AR and VR during 2015-2024. This research method used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) procedures to collect data from publications focusing on high-quality research results. The data were analyzed and identified using MS Excel software and VOSviewer to visualize various critical metadata obtained in the Scopus database. Notably, publication trends and distribution patterns, the contributions of authors, the geographical spread of publications, and the identification of significant publication sources were all essentials for analyzing the opportunities and challenges within the context of vocational education. The results of this study identified an augmenting growth of publication trends from 2015-2023, including the country of origin of prominent authors such as Bacca et al. (Spain), Babu et al. (India), and Lerner et al. (Germany), whose research results have been proven to impact the primary reference in the field of vocational education in the utilization of AR and VR. They are widely cited and have become the primary references for other authors. Consequently, this bibliometric-based research underscores the potential of AR and VR technologies to improve vocational education by enhancing motivation, educational access, personalized learning, collaboration, and reducing operational costs.peerReviewe
Frictional Behavior of Chestnut (Castanea sativa Mill.) Sawn Timber for Carpentry and Mechanical Joints in Service Class 2
No full textLa madera está llamada a convertirse en el material de construcción del futuro. Cuando se gestiona adecuadamente, es un material renovable con propiedades mecánicas únicas; lo que ha llevado al aumento de la demanda de madera de frondosas, incluida la Castanea sativa Mill., objeto de esta investigación, para aplicaciones estructurales. Aunque el Eurocódigo 5-2 ofrece coeficientes de fricción para madera, la información sobre frondosas es limitada. Sin embargo, estos coeficientes desempeñan un papel fundamental en las simulaciones numéricas en las que interviene la fricción, permitiendo la optimización de las uniones y, por extensión, de la integridad estructural global. Por ello, se evaluaron muestras con un contenido de humedad del 15% y 18% (Clase de servicio 2) para varias orientaciones de fricción madera-madera y madera-acero. Los resultados proporcionan una base de datos experimental para las simulaciones numéricas y ponen de relieve la influencia de la humedad en el fenómeno de stick-slip y en el valor de los coeficientes estático y dinámico que al 18% de humedad alcanzaron cifras de 0,70 y 0,48 para madera-madera y de 0,5 y 0,50 para madera-acero. El aumento fue de alrededor del 50% para la fricción madera-madera y de más del 170% para los pares madera-acero. Además, los resultados demostraron la existencia de una relación entre ambos coeficientes y la validez del enfoque de estimación lineal dentro de la humedad del 12-18% aplicada habitualmente a las maderas blandas.Wood is poised to become a material of choice for future construction. When appropriately managed, it is a renewable material with unique mechanical properties. Thus, there has been a growing demand for hardwoods, including Castanea sativa Mill., the focal point of this investigation, for structural applications. Albeit in a limited capacity, Eurocode 5-2 offers friction coefficients for softwoods, but it falls short for hardwoods. These coefficients play a critical role in numerical simulations involving friction, enabling the optimization of joints and, by extension, the overall structural integrity. Test samples were evaluated at 15% and 18% moisture content (Service Class 2) for various orientations of timber-to-timber and timber-to-steel friction. The results provide an experimental database for numerical simulations and highlight the influence of moisture on the stick–slip phenomenon, which was absent for the timber-to-timber tests, as well as on the rising friction values. At 18%, the static and kinetic coefficients were 0.70 and 0.48 for timber-to-timber and 0.5 and 0.50 for timber-to-steel. The increase was around 50% for timber-to-timber friction and over 170% for timber-to-steel pairs. Moreover, the findings proved a relationship between both coefficients and the validity of the linear estimation approach within the 12–18% moisture commonly applied to softwoods.This research was funded by Junta de Extremadura and by the European Regional Development Fund of the European Union through grants GR21163 and GR21091peerReviewe