Enseñanzas Técnicas

Hydrogen embrittlement in pre-loaded sharply-notched samples of cold-drawn pearlitic steel wires for prestressed concrete structures: a fractographic analysis

Thu, 01 Jan 2026 00:00:00 GMT

[EN]Hydrogen embrittlement (HE) is a primary cause of in-service failure of pearlitic prestressing steels, compromising the long-term durability and safety of prestressed concrete structures. This fracture process causes a material brittle fracture due to hydrogen-assisted micro-damage (HAMD). The main stage of HE is hydrogen transport by diffusion towards critical locations, a process highly sensitive to hydrostatic stress and plastic strain gradients. Accordingly, different HAMD scenarios to analyse HE in prestressing steels are defined in this study by modifying the stress and strain fields through sharp notches and mechanical preloading to induce residual stress and strains. To achieve this goal, two sharply-notched geometries were considered varying notch depth, shallow notch and deep notch. Both preloaded (90% of in-air fracture load) and un-preloaded notched samples were tested under a constant loading (70% of in-air fracture load) up to final fracture in the presence of an environment (saturated solution of Ca(OH)2 with 0.1 g/l NaCl) under electrochemical conditions (pH =12.5, E = −1200 mV SCE, saturated calomel electrode) promoting HE. Fractographic analysis via SEM of the fracture surfaces was performed to analyse the variations on the HAMD scenarios. The obtained results reveal different HE behaviours: shallow notches exhibited highly localized hydrogen damage and shorter time-to-failure, whereas deep notches resulted in more distributed damage and extended fracture lives.

Evaluación transfronteriza del tejido empresarial especializado en fabricación aditiva

Wed, 01 Jan 2025 00:00:00 GMT

[ES]En este trabajo, se lleva a cabo una investigación prospectiva utilizando fuentes abiertas para identificar y analizar las organizaciones que se benefician de la fabricación aditiva en la región transfronteriza entre el oeste de España y el norte de Portugal. El objetivo es evaluar la especialización empresarial en el contexto de esta tecnología propia de la Industria 4.0 en dos regiones caracterizadas por procesos de despoblación y desindustrialización. La metodología adoptada incluye una búsqueda sistemática basada en criterios predefinidos, seguida de un análisis cuantitativo en base a tres factores de estratificación: tamaño organizacional, objetivos empresariales, localización geográfica, cifras de venta y número de empleados. Además, se realiza un análisis cualitativo y heurístico de la información accesible sobre las organizaciones clave, explorando su vinculación con el desarrollo socioeconómico regional. [EN]In this paper, a prospective investigation is conducted using open sources on organizations benefiting from additive manufacturing in the cross-border region between western Spain and northern Portugal. This work aims to assess business specialization within the framework of this Industry 4.0 technology in two areas affected by depopulation and deindustrialization processes. The adopted methodology includes a systematic search based on predefined criteria, followed by a quantitative analysis based on three stratification factors: company size, business objectives, and geographic location. Additionally, a qualitative and heuristic analysis of open information from key organizations and their relationship with regional socio-economic development is carried out.

Joint Evaluation of Satellite-Derived Potential Field Data for the Delineation of Favourable Geothermal Areas in the Iberian Peninsula

Thu, 01 Jan 2026 00:00:00 GMT

Identifying favourable zones for geothermal exploration at the regional scale remains challenging, particularly in areas where conventional geophysical surveys are spatially limited or economically unfeasible. This study presents an integrated framework for delineating geothermal favourability across the Iberian Peninsula using global gravity and magnetic products combined with subsurface thermal information. EGM2008, WGM2012, EMAG2, and WDMAM2 were compared and harmonized through geostatistical modelling, anisotropic ordinary kriging, and common-grid processing. Potential-field transformations and spectral coherence analysis were used to derive a Geophysical Favourability Index (FI_geof). This index was integrated with temperature at 100 m depth using weighted fuzzy logic, applying FuzzyLinear and FuzzyLarge membership functions with a 60% FI_geof and 40% temperature weighting, to obtain the Geothermal Favourability Index (FI_geot). Quantitative comparison and cross-validation indicated that EGM2008 and EMAG2 were the most suitable primary reference products within their respective datasets, whereas WGM2012 and WDMAM2 provided complementary regional-scale information. The fuzzy integration identified the highest favourability mainly in Galicia and the Levante–Betic sector, where elevated FI_geot values coincide with heat-flow values of approximately 96–154 mW m−2 and comparatively high geothermal gradients. Around 20% of the study area was classified within the highest favourability category. The resulting FI_geot should be interpreted as a regional screening and prioritization tool rather than as direct evidence of an exploitable geothermal resource. Overall, the proposed methodology provides a reproducible approach for identifying priority areas for further geothermal investigation in large and incompletely characterized regions.

From Geospatial Assessment to Road Thermal Management: A Digital Framework for Climate-Resilient Infrastructure Using Low-Enthalpy Geothermal Energy

Thu, 01 Jan 2026 00:00:00 GMT

[EN] Extreme weather events increasingly affect the safety, durability, and operational performance of road infrastructure, creating the need for sustainable thermal management solutions. Among the available technologies, low-enthalpy geothermal systems offer significant advantages by providing continuous heating and cooling capabilities with reduced environmental impact compared to conventional maintenance practices. This study presents the methodology developed within the GEO-ROAD project to assess shallow geothermal resources across Spain and support the future deployment of geothermal road systems. The proposed framework integrates geological, thermal, and satellite-derived geophysical information through a unified GIS-based workflow, combining multivariate statistical analysis, map algebra, and automated geospatial processing to generate a regional geothermal potential model. In addition to conventional geological characterization, the methodology incorporates magnetic and gravity data from satellite missions, airborne surveys, and ground-based observations to improve the spatial representation of subsurface conditions. The resulting geothermal potential assessment constitutes a key component of the GEO-ROAD digital platform, where it will be combined with climatic risk maps and road infrastructure information to identify the most suitable locations for geothermal applications. By linking geothermal resource assessment with infrastructure-oriented decision-making, the proposed methodology provides a scalable and transferable framework for supporting the planning of sustainable and climate-resilient road thermal management systems.

Artificial Intelligence for Cultural Heritage Characterization: Towards Scalable and Sustainable Territorial Inventories

Thu, 01 Jan 2026 00:00:00 GMT

[EN] The depopulation of rural areas across Southern Europe has accelerated the deterioration and disappearance of cultural heritage assets, many of which remain undocumented, undervalued, or at risk. This article presents a hybrid methodology that combines AI techniques with expert knowledge to improve the identification, classification, and validation of cultural heritage in rural territories. The proposed system processes unstructured textual data to extract and categorize information on tangible and intangible heritage elements. A pilot case study was carried out in the Valle de Amblés and Sierra de Ávila (province of Ávila, Spain), a region characterized by severe demographic decline but high heritage potential. Four municipalities (Amavida, Cardeñosa, La Torre, and Solosancho) were selected for testing based on heritage diversity, available documentation, and accessibility. In each case, AI-generated outputs were compared with manually curated validation files to assess the detection performance and applicability of the system. Results show that while traditional fieldwork and historical interpretation remain essential, AI can significantly enhance the speed and scalability of heritage documentation, particularly in under-resourced areas. The methodology reinforces the value of interdisciplinary collaboration and supports the development of territorial heritage strategies for sustainable rural regeneration.

Compression performance of composite plates after multi-site impacts: A combined experimental and finite element study

Sun, 01 Jan 2023 00:00:00 GMT

[EN]This paper reports on a study of the damage tolerance of carbon fibre reinforced polymer plates, used in aircraft fuselage, subjected to multi-site impacts. A new fixture was designed to perform sequential low-velocity impacts at different locations on plates with two different thicknesses, representing upper and lower fuselage panels. The residual strength in compression was measured using a new compression-after-impact rig designed to prevent global buckling of thin plates. Experimental results indicated that compared to single impacts, multi-site impacts can reduce the residual strength of the thin plates, but not the thick plates. To explain this difference, a detailed finite element model was developed, which enabled modelling of multi-site impacts and compression after impact in one simulation. Simulations suggested that the second impact damage changes the buckled shape prior to failure for the thin plates. A parametric analysis on key material parameters showed that they have a small effect on the residual compressive strength. This work can help to improve the design of aircraft panels with respect to threats posed by multi-site impacts.

A material selection approach for protecting carbon/epoxy laminates against single and repeated low-velocity impacts

Mon, 15 Jan 2024 00:00:00 GMT

[EN]This paper evaluates the impact performance of various materials against single and repeated low-velocity impacts. The objective is to identify a lightweight, thin, and cost-effective bumper that can effectively protect a composite aircraft structure. Drop-weight impact tests were performed on eight candidate materials with similar areal densities, including three 3D woven and three 2D woven composites, an aluminium alloy (Al 7075 T6) and an aluminium foamed sandwich. To enable a comparison of impact performance across materials with different characteristics, a normalisation method was defined for both single and repeated impact loading. The relationship between single and repeated low-velocity impacts was also explored. Finally, the influence of adding a polymeric foam on the amount of energy transmitted to the composite airframe was also discussed. The results indicate that, overall, the 3D woven composites exhibited superior impact performance in all tested scenarios.

A smart pen prototype with adaptive algorithms for stabilizing handwriting tremor signals in Parkinson’s disease

Wed, 06 Aug 2025 00:00:00 GMT

[EN] This study presents a smart pen prototype designed to dynamically mitigate hand tremors, thereby enhancing writing quality and user comfort for individuals with conditions such as Parkinson’s disease. The device employs an accelerometer for real-time tremor detection, a microcontroller for rapid data processing, and a vibration motor to counteract tremor effects. Adaptive algorithms—including Fx-LMS, Fx-NLMS, a combined Fx-LMS/NLMS approach, RLS, and the Kalman Filter—were evaluated using signals from the NewHandPD dataset. Simulation results revealed that although the RLS algorithm achieved the lowest mean square error, the Kalman Filter converged approximately eight times faster, a finding that was confirmed through microcontroller tests and further validated on an orbital shaking table under constant and variable tremor conditions. These outcomes underscore the potential of the Kalman Filter as a non-invasive, adaptive solution for real-time tremor mitigation in assistive writing devices. Future improvements may include integrating additional sensors and further optimizing microcontroller performance to enhance overall adaptability and accuracy. [ES] Este estudio presenta un prototipo de bolígrafo inteligente diseñado para mitigar de forma dinámica los temblores de la mano, mejorando así la calidad de la escritura y la comodidad del usuario para personas que padecen enfermedades como el párkinson. El dispositivo utiliza un acelerómetro para la detección de temblores en tiempo real, un microcontrolador para el procesamiento rápido de datos y un motor de vibración para contrarrestar los efectos de los temblores. Se evaluaron algoritmos adaptativos —entre ellos, Fx-LMS, Fx-NLMS, un enfoque combinado de Fx-LMS/NLMS, RLS y el filtro de Kalman— utilizando señales del conjunto de datos NewHandPD. Los resultados de la simulación revelaron que, aunque el algoritmo RLS alcanzó el error cuadrático medio más bajo, el filtro de Kalman convergió aproximadamente ocho veces más rápido, un hallazgo que se confirmó mediante pruebas con el microcontrolador y se validó posteriormente en una mesa de agitación orbital en condiciones de temblor constantes y variables. Estos resultados subrayan el potencial del filtro de Kalman como solución adaptativa y no invasiva para la mitigación de los temblores en tiempo real en dispositivos de asistencia a la escritura. Las mejoras futuras podrían incluir la integración de sensores adicionales y una mayor optimización del rendimiento del microcontrolador para mejorar la adaptabilidad y la precisión generales.

An analytical review of optimization techniques in information retrieval for enhanced decision support

Wed, 19 Nov 2025 00:00:00 GMT

[EN] As digital content continues to evolve, enhancing Information Retrieval (IR) systems is crucial to improve their performance, relevance, and ability to handle increasingly large datasets. This systematic review examines current advancements in IR optimization strategies, with a focus on the paradigm shift from traditional heuristics to AI-driven models. Following the PRISMA 2020 guidelines, an exhaustive literature search was conducted for publications between January 2013 and June 2025, employing a hybrid screening approach that combined Natural Language Processing (NLP) automated filtering with manual expert review. Our findings underscore the growing importance of hybrid models that leverage deep learning, particularly transformer architectures, for tasks such as personalization and relevance feedback, which have demonstrated significant performance improvements. However, significant challenges such as algorithmic bias, computational complexity, and domain-specificity impede wider implementation. This review provides a comprehensive roadmap of the IR optimization landscape, identifies persistent ethical challenges, and explores emerging research frontiers, such as quantum IR and generative models, thereby offering actionable insights for both researchers and practitioners in the decision analytics field. [ES] A medida que los contenidos digitales siguen evolucionando, es fundamental mejorar los sistemas de recuperación de información (IR) para aumentar su rendimiento, su relevancia y su capacidad para gestionar conjuntos de datos cada vez más voluminosos. Esta revisión sistemática analiza los avances actuales en las estrategias de optimización de la recuperación de información, centrándose en el cambio de paradigma de las heurísticas tradicionales a los modelos basados en la inteligencia artificial. Siguiendo las directrices PRISMA 2020, se llevó a cabo una búsqueda bibliográfica exhaustiva de publicaciones entre enero de 2013 y junio de 2025, empleando un enfoque de selección híbrido que combinaba el filtrado automatizado mediante el procesamiento del lenguaje natural (PLN) con la revisión manual por parte de expertos. Nuestros resultados subrayan la creciente importancia de los modelos híbridos que aprovechan el aprendizaje profundo, en particular las arquitecturas de transformadores, para tareas como la personalización y la retroalimentación de relevancia, que han demostrado mejoras significativas en el rendimiento. Sin embargo, retos importantes como el sesgo algorítmico, la complejidad computacional y la especificidad del dominio impiden una implementación más amplia. Esta revisión ofrece una hoja de ruta exhaustiva del panorama de la optimización de la búsqueda de información, identifica los retos éticos persistentes y explora las fronteras emergentes de la investigación, como la búsqueda de información cuántica y los modelos generativos, ofreciendo así conocimientos prácticos tanto para investigadores como para profesionales del campo del análisis de la toma de decisiones.

Radar Technologies for Space Debris Detection: A Bibliometric Review

Fri, 28 Aug 2026 00:00:00 GMT

The proliferation of artificial objects in Earth’s orbit has transformed space debris into one of the most critical challenges to space sustainability. Radar technologies play a pivotal role in the detection, tracking, and characterization of these non-functional objects, providing the backbone for global Space Situational Awareness (SSA) and collision avoidance systems. This study presents a comprehensive bibliometric analysis of radar-based space debris detection research published between 2005 and 2025. Using data retrieved from the Scopus and Web of Science databases, a curated dataset of 557 peer-reviewed journal articles was examined. The analysis explores publication trends, institutions, countries, and journals, as well as co-citation and keyword co-occurrence networks to map the intellectual and thematic structure of the field. Results reveal a sustained annual growth rate of 3.76%, with China and the United States leading global research output. Core motor themes—such as space-based radar, synthetic aperture radar, and remote sensing—define the technological foundation of the domain, while emerging clusters reflect growing interest in artificial intelligence and active debris removal. The study highlights a high degree of collaboration among researchers but significant geographic concentration of capabilities. By unveiling the evolution, collaboration patterns, and conceptual frontiers of radar-based space debris research, this work provides a quantitative foundation to guide future investigations and policy strategies aimed at ensuring long-term orbital sustainability.

GIS-Based Evaluation for Identifying Road Sections Vulnerable to Extreme Winter Weather Conditions

Thu, 01 Jan 2026 00:00:00 GMT

[EN] Road infrastructures are fundamental for ensuring connectivity, safety, and the efficient functioning of transportation networks. However, extreme weather conditions, particularly low temperatures and ice formation, pose significant risks to user safety and road conditions. This research focuses on the development of a geospatial model designed to identify road sections exposed to these harsh weather conditions. The model integrates different sources of information, including meteorological and satellite data, topographic information, and road maintenance plans, through a consistent methodology for data processing and analysis. A combination of geospatial analysis and advanced processing techniques was employed to identify and map regions most vulnerable to the formation of ice. The results show good spatial agreement between the areas identified by the model and the available local information, supporting its ability to characterize areas with greater susceptibility to winter-related hazards. This work highlights the potential of the developed geospatial model to support the planning of preventive and maintenance measures on roads. By providing spatial information on susceptibility to low temperatures and ice formation, the model can serve as a decision-support tool for road management, contributing to the planning of targeted interventions and improved road safety. Overall, this study underscores the importance of integrating advanced geospatial techniques into infrastructure management to improve response strategies in the face of extreme weather events.

Lightweight Skin Lesion Segmentation for Edge Deployment: A Critical Review of Architectures, Accuracy Compensation, and Clinical Translation

Thu, 09 Apr 2026 00:00:00 GMT

[EN]Automated skin lesion segmentation via deep learning has achieved remarkable accuracy in controlled laboratory settings, yet its clinical translation to point-of-care (PoC) edge devices remains fundamentally constrained by the computational demands of state-of-the-art architectures. This review systematically bridges the gap between algorithmic innovation and hardware-aware deployment by presenting a critical analysis spanning three interconnected dimensions: 1) architectural evolution from convolutional neural networks (CNNs) through Vision Transformers to emerging linear-complexity State Space Models (e.g., Mamba), evaluated against a unified efficiency–accuracy Pareto framework rather than isolated accuracy rankings; 2) mathematical formalisation of lightweighting-induced precision degradation and its compensation via knowledge distillation, structural reparameterisation, and frequency-domain enhancement, with explicit assessment of evidence quality and reproducibility across studies; and 3) empirical deployment profiling across heterogeneous edge platforms including NVIDIA Jetson, Intel OpenVINO, and mobile processors. Through a multi-dimensional evaluation framework integrating spatial overlap (Dice), boundary fidelity (HD95), and on-device throughput (FPS), supplemented by a meta-analysis of dataset usage biases and validation protocol inconsistencies, we establish that heterogeneous multi-paradigm fusion architectures can preserve clinical-grade segmentation quality under severe resource constraints—provided that evaluation methodologies are standardised. Critically, our quantitative analysis of 36 reviewed studies reveals that approximately 65% of reported performance figures are derived from non-standardised data splits, rendering direct cross-study comparisons statistically unreliable. We further identify critical open challenges—including cross-domain generalisation, hardware–algorithm co-design, demographic fairness, and edge-native federated learning—an...

Engineering a dual stimuli-responsive platform for post-surgical breast cancer treatment

Thu, 01 Jan 2026 00:00:00 GMT

[ES] Esta tesis doctoral se ha centrado en el desarrollo de una plataforma dual termo/pH-sensible para el tratamiento localizado del cáncer de mama tras la resección quirúrgica del tumor para la erradicación de células tumorales en el tejido mamario y prevención de recurrencias locales. El objetivo principal ha sido combinar la administración local de fármacos, mediante el desarrollo de una matriz de hidrogel inyectable y termosensible, con mecanismos de liberación pH-sensible basados en nanocarriers, capaces de aumentar la eficacia terapéutica y reducir los efectos adversos de las terapias sistémicas convencionales. La novedad en esta tesis doctoral respecto a los sistemas de respuesta dual reportados reside en la transferencia de la pH-sensibilidad de la matriz del hidrogel al nanocarrier incorporado, estableciendo un proceso de síntesis y optimización de las estrategias en cada componente del sistema híbrido de forma paralela, presentando la oportunidad de un diseño más adaptable a cada estrategia y mayor potencial sinérgico, incrementando su actividad anticancerígena. La primera etapa de la investigación estuvo dedicada al estudio de coacervados basados en alginato y gelatina A, buscando la síntesis del nanocarrier pH-sensible. Se analizó de forma detallada la influencia de variables como el pH, la temperatura de síntesis, el pretratamiento térmico de la gelatina y la relación Alginato:Gelatina A. Los resultados demostraron que el estado estructural de la gelatina desempeña un papel fundamental en la formación y estabilidad de los coacervados. El calentamiento favoreció el desenredo parcial de las cadenas de gelatina, permitiendo obtener coacervados más homogéneos y estables, incrementando el número de interacciones electrostáticas. La caracterización mediante dispersión dinámica y estática de luz (zetasizer) y turbidimetría permitió identificar formulaciones con tamaños nanométricos y baja polidispersión. Sin embargo, se observó un fenómeno de histéresis térmica por el cual las propiedades de los coacervados se deterioraban tras varios días a temperatura ambiente, a pesar de poder recuperarse parcialmente mediante ciclos de recalentamiento. Este comportamiento también fue confirmado mediante estudios reológicos, que pusieron de manifiesto la incompatibilidad de estas partículas coacervadas con una matriz que pudiera ser usada como reservorio de principios activos en administración local. Por lo tanto, la siguiente etapa de la tesis estuvo centrada en el desarrollo de otra alternativa para el componente pH-sensible del sistema dual. Para ello se sintetizaron liposomas mediante hidratación de capa fina y extrusión, optimizando tanto las condiciones de preparación como la composición lipídica. Los sistemas obtenidos presentaron tamaños próximos a 100 nm, muy baja polidispersión y una elevada estabilidad por periodos superiores a 3 semanas. Para conferir la pH-sensibilidad, se desarrolló una estrategia basada en el recubrimiento de liposomas con polímeros Eudragit (EU). Más concretamente, el uso de dos formulaciones que presentaban perfiles de liberación con respuesta opuesta al pH se llevó a cabo para expandir el uso de liberaciones de fármaco en sistemas liposomales. Para el primer recubrimiento (EU S100, liberaciones alcalinas) fue necesario modificar previamente la carga superficial de los liposomas mediante estearilamina, permitiendo posteriormente su recubrimiento mediante interacciones electrostáticas, formando agregados micrométricos. Por otro lado, el recubrimiento con EU EPO (liberaciones ácidas) sí presentó sistemas coloidales de tamaños nanométricos. Los estudios de tamaño, potencial zeta y microscopía confirmaron la formación de estructuras recubiertas estables y reproducibles. Una vez seleccionadas las formulaciones más prometedoras, se evaluó la encapsulación y liberación del fármaco antitumoral 5-fluorouracilo (5FU). La eficiencia de encapsulación superó el 90% y los ensayos de liberación demostraron una clara dependencia del pH. Los sistemas recubiertos mostraron una capacidad significativamente mayor para modular la liberación dentro de cada rango de respuesta de la formulación de EU seleccionada, validando la estrategia de respuesta al pH. Adicionalmente, se estudió validación biológica de los sistemas desarrollados. Para ello se realizó una estancia de investigación en la Universidad de Birmingham, donde se adquirió experiencia en cultivos celulares y técnicas de evaluación de actividad terapéutica. En primer lugar, se determinó la sensibilidad al 5FU de fibroblastos sanos HS-5 y de la línea celular de cáncer de mama BT-474. Posteriormente, los estudios de viabilidad celular demostraron que las formulaciones liposomales eran biocompatibles. Adicionalmente, cuando el fármaco era encapsulado, las formulaciones pH-sensibles mostraban un comportamiento dependiente del microambiente celular. Teniendo en cuenta la aplicación en terapias anticancerígenas, los liposomas recubiertos con Eudragit EPO combinaron una elevada internalización celular con una liberación favorecida en condiciones ácidas. Como resultado, se alcanzaron niveles de mortalidad superiores al 95% en células tumorales, manteniendo simultáneamente una elevada viabilidad en fibroblastos sanos, confirmado la compatibilidad con la aplicación. Posteriormente, la investigación se orientó hacia el desarrollo de hidrogeles termosensibles basados en el poloxámero PF-127. Este polímero presenta la capacidad de formar geles al aumentar la temperatura debido a fenómenos de agregación micelar, lo que lo convierte en un candidato atractivo para aplicaciones inyectables. Sin embargo, los hidrogeles obtenidos únicamente con PF-127 mostraban una liberación demasiado rápida del fármaco. Con el fin de reforzar la estructura del hidrogel, se estudió la incorporación de diferentes polisacáridos con diferentes conformaciones estructurales: alginato (lineal), goma gellan (ramificado), goma santana (helicoidal) y levan (coloides auto-ensamblados). Cada uno de ellos mostró interacciones específicas con la red micelar del poloxámero, mejorando su comportamiento reológico, su temperatura de gelificación y su estabilidad estructural. Los ensayos reológicos demostraron que la incorporación de polisacáridos permitía mantener la transición sol-gel a temperaturas compatibles con la aplicación biomédica, mientras que aumentaba su elasticidad y resistencia. En estudios de liberación de fármaco, los hidrogeles con polisacáridos incorporados eliminaron prácticamente la liberación rápida inicial observada en el poloxámero puro, y prolongaron la liberación del fármaco más de cuatro veces respecto al sistema original. Estos resultados confirmaron que la incorporación de polisacáridos reducía la porosidad efectiva de la red y dificultaba tanto la difusión del medio como la degradación de la estructura, soportados por tasas de degradación y constantes cinéticas obtenidas por el ajuste a un modelo matemático. Una vez optimizados ambos componentes por separado, los liposomas pH-sensibles fueron incorporados a la matriz del hidrogel termosensible para generar la plataforma híbrida de respuesta dual. Los estudios reológicos confirmaron que la presencia de los liposomas no alteraba la capacidad de agregación micelar del poloxámero. Adicionalmente, su combinación permitió conservar el comportamiento dual del sistema. Los hidrogeles mostraron una elevada biocompatibilidad y mantuvieron la capacidad de liberar selectivamente el fármaco hacia entornos tumorales. Aunque la liberación fue más lenta debido a la resistencia difusional impuesta por la matriz polimérica, la actividad terapéutica siguió siendo eficiente. Finalmente, la formulación híbrida fue evaluada en esferoides tridimensionales de cáncer de mama, un modelo más representativo del entorno tumoral real. Los resultados demostraron una capacidad superior para desintegrar la estructura de los esferoides y reducir la viabilidad celular respecto al fármaco libre. En conjunto, los resultados obtenidos validan una estrategia basada en la combinación de un hidrogel termosensible inyectable y liposomas pH-sensibles como plataforma para el tratamiento localizado del cáncer de mama post-quirúrgico. El sistema desarrollado permitió aprovechar simultáneamente la administración local, la liberación sostenida y el direccionamiento hacia el microambiente tumoral, constituyendo una alternativa prometedora para futuras aplicaciones en terapia postquirúrgica.; [EN] Nowadays, the procedure for an early stage non-metastatic diagnosed breast cancer is the breast-conserving therapy, consisting of tumour resection therapy by lumpectomy followed by breast irradiation to prevent local recurrences. Despite late advances, the radiotherapy off-targeting toxicity, as well as the alternative chemotherapies based on drug delivery systems systemically administered present major drawbacks. The poor therapeutic efficiency, resulting from limited drug accumulation at tumour site, together with systemic toxicity, constitute the main limitations of systemic administration. Since residual tumour cells responsible for recurrence are predominantly located within the surgical bed, the development of local therapies targeting these cells can help overcome the current limitations associated with tumour relapse. Therefore, this doctoral thesis addresses this challenge through the design and development of a dual stimuli-responsive local drug delivery platform for post-surgical therapy which presents combined thermo-sensitivity by an injectable hydrogel matrix, and pH-sensitivity by an engineered nanocarrier. These responses exploit two basic features that can be found in the surgical bed: Physiological temperature to induce gelation after injection, providing a locally administered strong drug depot, and the acidic tumour microenvironment, providing a reproducible targeting strategy. The final drug delivery system is based on a PF-127 hydrogel network incorporating Eudragit® EPO coated liposomes encapsulating the anticancer drug 5-fluorouracil (5-FU) as a model chemotherapeutic agent. However, the first approach consisted of developing alginate-gelatin A coacervates for pH-responsive strategy. Their synthesis optimization was accomplished by the study of process variables, including temperature and pH, obtaining nano sized coacervates systems of 500-750 nm with low polidispersity index (PDI <0.25). Nonetheless, their dependence on temperature and pH resulted in instability under physiological conditions, preventing their use for the intended application. Consequently, new pH-responsive approaches were explored. In this case, liposomes were selected due to their current use in clinic, showing their high biocompatibility, efficiency, and versatility as vesicles resembling cellular membranes. Conventional liposomes were successfully synthesized and optimized via sonication and extrusion, obtaining a stable small unilamellar vesicle system (85 nm) with narrow size distribution (PDI < 0.1) for a 3-week period, able to encapsulate more than 90% of loaded 5-FU. Nevertheless, they exhibited fast drug release (under 8h) with no pH-response, evidencing a non-specific mechanism. Therefore, strategies to introduce pH-responsive release were investigated. In order to preserve the liposomes stability at physiological conditions, a surface modification rather than the conventional method of composition alteration was preferred. Regarding this, an innovative coating procedure with Eudragit® family of polymers offered a promising alternative. Moreover, the broad range of Eudragit® formulations, providing opposite pH-responsive behaviours depending on the intended application, enabled the optimization of the coating process to obtain a versatile liposomal platform. Accordingly, two oppositely pH-responsive coatings (Eudragit® S100 and EPO) were implemented to evaluate drug release under contrasting conditions, thereby expanding the potential applicability of stable liposomes at physiological conditions for enhancing cancer therapy through different administration routes. Eudragit® S100 (EU S100, designed for alkaline releases) coating procedure provided liposomal micron scale aggregates due to its high molecular weight and behaviour in aqueous solution. Meanwhile, Eudragit® EPO (EU EPO, designed for acidic releases) showed stable liposomal systems slightly larger (114 nm) but still monodisperse (PDI <0.15), presenting a promising formulation for the thesis objective. Moreover, both coatings showed higher encapsulation efficiencies than the conventional liposomes, and their releases were delayed until 24 h, preventing up to 50% of drug release in insoluble pH ranges for each coating. Mathematical modelling supported that insoluble coatings introduced a change in release mechanism, whilst supporting diffusion as the predominant one in Higuchi and first order fittings. This presented potential applications for alkaline delivery in colon or intestine from oral formulations (EU S100), and more importantly, acidic tumour microenvironment targeting (EU EPO). In fact, cell viability studies showed biocompatibility of all developed liposomal formulations. The pH-response of both coatings was validated through MTT assays in healthy fibroblast (HS-5) and breast cancer (BT-474) cell lines. Specifically, EU EPO coated liposomes enhanced cytotoxicity over 30% more than the rest of formulations in breast cancer cells after 72h, preserving fibroblasts viability. Therefore, tumour targeting was confirmed by in vitro studies. In parallel, a thermo-responsive injectable PF-127 hydrogel platform was developed for the local drug delivery reservoir. Comprehensive rheological analyses were used to characterize the thermo-response and evaluate the gelation completion temperature, the viscoelasticity and viscosity of the system, and ultimately, the suitability for injection and sustained release. Since PF-127 hydrogel showed fast degradation, different polysaccharides were implemented in the hydrogel network and the effect of their concentrations as well as their structural conformations was studied. Implemented polysaccharides matrices presented improved rheological properties (G’ from 8 to 11-18 kPa) and more resistance against flow (viscosities from 4.1 to 6.1-7.1 Pa·s), establishing final optimal formulations for local administration. These formulations provided a more prolonged 5-FU release, reaching up to four times (450 min) the release time that PF-127 hydrogel exhibited (90 min). Moreover, mathematical modelling confirmed that the polysaccharides implementation caused an additional diffusional resistance based on their concentration and structural complexity, decreasing the degradation rate and resisting water permeation through the matrix. The final hybrid dual-responsive platform was synthesized by incorporating the pH-responsive Eudragit® EPO coated liposomes into the thermo-responsive injectable PF-127 hydrogel matrix. Characterization techniques showed the successful liposomal incorporation into the hydrogel matrix via scanning electron microscopy, as well as improved viscoelastic properties (G’ of 15 kPa, and viscosity of 6.8 Pa·s) of the system via rheology. Moreover, the pH-responsiveness was preserved, as demonstrated by drug release studies. In fact, hydrogel incorporation introduced an additional diffusion barrier, leading to a sustained 5-FU release for up to 48h, where up to 50% of drug release was prevented for coating insolubility range. This insolubility proved once again a change of release mechanism in one and two-stage models fitting, whilst the hydrogel matrix delayed release was supported by lower kinetic constants. Finally, biological validation of the dual-responsive system was performed in 2D cell cultures and 3D breast tumour spheroids, for a better prediction of its in vivo behaviour. 2D cell assays replicated the results shown in liposomal systems, with the only exception that tumour cell mortality was slightly reduced (from 5% cell viability to 15% in 3 days) for the dual-responsive formulation, which was attributed to the delayed 5-FU release. However, the tumour targeting capacity was preserved. This was further supported by the results obtained in 3D tumour spheroids assays, where the dual-responsive hydrogel targeted successfully cancer cells promoting its therapeutic efficiency, showing disaggregated and disintegrated spheroids compared to off-targeting drug solution (from 40% cell viability in 5-FU solution to 28% in dual-responsive hydrogel after 3 days). Overall, this thesis presents an engineered dual-responsive local drug delivery platform for post-surgical breast cancer treatment. The innovative strategy of combining two separately optimized stimuli-responses for local administration and tumour targeting presented improvements regarding the current therapies: High therapeutic efficiency, and decreased systemic toxicity.

Localización, diagnosis y puesta en valor del Imperial Monasterio Cisterciense de Santa María de Valparaíso. Mediante la aplicación de técnicas geofísicas, fotogrametría, y láser 3D

Wed, 01 Jan 2025 00:00:00 GMT

[ES] Este artículo documenta un proyecto de investigación integral centrado en el Imperial Monasterio de Santa María de Valparaíso (Zamora), un cenobio cisterciense en estado de ruina y enterramiento. La metodología se fundamenta en un enfoque rigurosamente multidisciplinar que articula el análisis histórico-documental con tres campos tecnológicos de vanguardia: prospección geofísica, diagnóstico de ingeniería civil y documentación geométrica digital (HBIM). Mediante la aplicación de la Tomografía de Resistividad Eléctrica 3D (ERT 3D), se logró la localización precisa de estructuras subterráneas, destacando el descubrimiento de una galería abovedada perteneciente a uno de los claustros. Esta detección se validó al contrastar los altos valores de resistividad con las referencias documentales previas (Ferrero, 1986; Rodríguez Miguel, 1910-1911). Complementariamente, el escaneo láser (LIDAR) y la fotogrametría generaron datos de alta densidad para la reconstrucción virtual hipotética en 3D (HBIM) de la iglesia (crucero y nave central) y del conjunto del resto de edificaciones, permitiendo el estudio paramétrico de sus elementos (dovelas y sillares). El trabajo persigue el levantamiento gráfico, la puesta en valor y la divulgación inmersiva (RV/RA) de este crucial patrimonio castellano, proporcionando una hoja de ruta metodológica para la gestión de ruinas monásticas.; [EN] This article documents a comprehensive research project centered on the Imperial Monastery of Santa María de Valparaíso (Zamora), a Cistercian monastery in a state of ruin and burial. The methodology is grounded in a rigorously multidisciplinary approach that integrates historical-documentary analysis with three cutting-edge technological fields: geophysical prospection, civil engineering diagnosis, and digital geometric documentation (HBIM). Through the application of 3D Electrical Resistivity Tomography (3D ERT), the precise location of underground structures was achieved, highlighted by the discovery of a vaulted gallery belonging to one of the cloisters. This detection was validated by crossreferencing the high resistivity values with previous documentary references (Ferrero, 1986; Rodríguez Miguel, 1910-1911). Additionally, laser scanning (LiDAR) and photogrammetry generated high-density data for the hypothetical 3D virtual reconstruction (HBIM) of the church (transept and central nave) and the rest of the architectural complex, enabling the parametric study of its elements (voussoirs and ashlars). This work aims to carry out the architectural survey, heritage enhancement, and immersive dissemination (VR/AR) of this crucial Castilian heritage, providing a methodological roadmap for the management of monastic ruins.

Harnessing Low-Enthalpy Geothermal Energy to Enhance Road Infrastructure Resilience: Insights from GEO-ROAD Project

Mon, 01 Jun 2026 00:00:00 GMT

‎[EN] Geothermal systems offer an effective solution for enhancing the resilience of road infrastructure to extreme weather events. Their key advantages (such as independence from external climatic conditions and the potential for continuous operation) make them significant improvement over conventional approaches, including de-icing or protecting road surfaces from high temperatures. Within this context, the GEO-ROAD project aims to develop a predictive platform to identify the most promising locations for the deployment of geothermal energy in road infrastructure. A central component of this research is the methodology used to characterize the subsurface energy resource across the study area (Spain) and to develop corresponding geothermal potential models. Following an initial geological and thermal assessment, a refined model is presented that integrates geophysical data from satellite missions, airborne surveys, and field measurements. Finally, this work highlights the importance of high-precision geothermal potential models, which provide a robust foundation for optimizing the use of geothermal energy, particularly in the road sector considered.

Immersive UAV training through simulated environments as a cross-disciplinary educational methodology for architecture and engineering education

Thu, 01 Jan 2026 00:00:00 GMT

[ES] La creciente integración de los UAV en arquitectura e ingeniería exige nuevas metodologías formativas adaptadas a contextos profesionales reales. Sin embargo, la enseñanza universitaria continúa limitada por restricciones normativas y condicionantes logísticos que reducen la práctica real de vuelo. Este trabajo presenta una metodología educativa inmersiva basada en simuladores profesionales combinados con controladores físicos, que permite desarrollar competencias técnicas, operativas y de toma de decisiones en un entorno seguro y repetible. La propuesta integra aprendizaje activo, misiones basadas en retos y evaluación por competencias, estructurándose en fases progresivas: selección de herramientas de simulación, aplicación de rúbricas iniciales y finales, análisis de resultados, transición a prácticas reales y mejora continua. Desde la perspectiva arquitectónica y de la edificación, la metodología facilita la formación en inspección de edificios, planificación de vuelos y captura de datos mediante fotogrametría y análisis térmico, ofreciendo un modelo escalable y transferible para la innovación educativa en educación superior.