idUS. Depósito de Investigación Universidad de Sevilla
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Amplified impacts of human activities: Non-linear responses of riverine microbial communities to distribution of land use
No full textRapid global urbanization poses considerable ecological risks to freshwater systems, notably leading to substantial reductions in microbial communities. To assess the impacts of human activities on these communities, we applied the high-throughput amplicon DNA sequencing to examine spatial variations in riverine microbial communities within an urbanized watershed. Coupled with the Geographical Detector Model, the effects of the land use were identified across the watershed. Results show that microbial communities were closely linked to the human-impacted land use patterns. The upstream region, dominated by forest cover (71%), exhibited the highest microbial population (3384 OTUs), whereas the urbanized downstream outlet (91% urban land) showed the lowest microbial population (471 OTUs). Additionally, the spatial distribution of the human-impacted land use appears to abruptly alter microbial pathways along the river. The spatial threshold effect of human-impacted land use is indicated by a Moran's I value exceeding 0.80. Notably, a 300-m buffer zone around different land uses seems to significantly influenced sediment microbial communities. Besides, the influence of land use on microbial communities is intensified by spatial drivers. For instance, agricultural land use was found to impact riverine Parcubacteria communities, with factor detector values increasing by over 30% in 400–500 m buffer zones. These findings provide new insights into the complex relationship between human activity and riverine microbial communities, highlighting important implications for ecosystem management in rapidly urbanization regions
Caves as a Refuge for Hominids and Carnivores in the Mousterian of the Southern Iberian Peninsula
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Gain Scheduling PI Voltage Control of Three-phase AC/DC Power Converters
No full textThis paper present a dc-Link voltage regulation strategy for a two-Level three-phase grid-connected power converter. Control objectives for this system are regulating the dc-link capacitor voltage to a user define set point and, tracking the grid current reference to inject or absorb the requested instantaneous active and reactive power. The proposed voltage controller has a PI Control structure, with adaptation of the gains depending on the observed error. In this way, the monitoring of the voltage reference can be intelligently optimized.Ministerio de Ciencia e Innovación PID2020-115561RB-C31Ministerio de Ciencia, Innovación y Universidades PID2020-115561RB-C32Ministerio de Ciencia e Innovación TED2021-131604B-I00Ministerio de Ciencia e Innovación TED2021-130613BI0
“But I Also like to Enjoy my Time, I’m Not a Student 24 Hours a Day”: Adolescents’ Perspectives About Organized Leisure and School Stress
No full textAlthough organized leisure has numerous benefits during adolescence, we still know relatively little about its role in school stress. The aim of this study was to provide insights into the role of participation in organized leisure-time activities in adolescents’ school stress. We used purposive sampling to select adolescents from high-stress and low-stress secondary schools from Andalusia (Spain), and conducted 24 focus groups with boys and girls from Grade 2 (13–14 years) and Grade 4 (15–16 years). Using thematic analysis, we identified three overarching themes. Participation in organized leisure can alleviate school stress, but it can also be stressful because it generates conflicting time demands with schoolwork. The study also hints at potential differences depending on the type of activity and provides valuable insights into gender differences in the choices made to skip or quit organized leisure, with implications for supporting adolescents’ regular organized leisure participation
Luminescent solar concentrators: Photo-stability analysis and long-term perspectives
No full textLuminescent Solar Concentrators (LSC) have been extensively analysed from the point of view of design to improve its performance, but there are still open questions about long-term stability at outdoor conditions, which reduce its commercial interest. A study of photo-stability of a LSC is presented in this work. The prototype consists in an organic dye, encapsulated at pilot scale (10 × 10 cm2) to reproduce real operating conditions. Outdoor monitoring and indoor aging tests are performed to evaluate what are the critical failures, their cause, and possible mitigation solutions to provide long-term stability to the LSC device. A correlation between encapsulating materials and dye photoluminescence properties is identified, which clarify the photo-degradation mechanism of the LSC. These results provide a better comprehension of the design strategies required to ensure the r
Economic model predictive control for periodic operation: a quadratic programming approach
No full textPeriodic dynamical systems, distinguished by their repetitive behavior over time, are prevalent across various engineering disciplines. In numerous applications, particularly within industrial contexts, the implementation of model predictive control (MPC) schemes tailored to optimize specific economic criteria was shown to offer substantial advantages. However, the real-time implementation of these schemes is often infeasible due to limited computational resources. To tackle this problem, we propose a resource-efficient economic model predictive control scheme for periodic systems, leveraging existing single-layer MPC techniques. Our method relies on a single quadratic optimization problem, which ensures high computational efficiency for real-time control in dynamic settings. We prove feasibility, stability and convergence to optimum of the proposed approach, and validate the effectiveness through numerical experimentsMinisterio de Ciencia, Innovación y Universidades PID2022-141159OB-I00Ministerio de Ciencia, Innovación y Universidades RYC2021- 033960-
Arte y ciencia. La inmolación de las células
No full textLa exposición "Arte y ciencia. La inmolación de las células" se llevó a cabo en el Museo Nacional de Ciencia y Tecnología (MUNCYT) en A Coruña, del 18 de julio al 30 de noviembre de 2024. Comisariada por Raquel Barrionuevo Pérez y Laura Nogaledo Gómez, la muestra reunió obras de artistas e investigadores de la Universidad de Sevilla, que exploran la intersección entre arte y ciencia. Este proyecto buscó fomentar un diálogo enriquecedor entre ambas disciplinas, destacando la importancia de la investigación y la creatividad en la comprensión de fenómenos biológicos y tecnológicos contemporáneos. A través de diversas obras, se abordaron temas como la autoinmolación celular y la relación entre lo ordinario y lo extraordinario, invitando a los visitantes a reflexionar sobre la fragilidad de la vida y el impacto de la tecnología en la existencia humana. La exposición también contó con la colaboración de instituciones como la Sociedad Española de Bioquímica y Biología Molecular y la Fundación Cajasol
