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Comparative analysis of kernel approximation methods and their ensemble architectures
No full textKernel methods offer strong performance in supervised learning, but their scalability remains a key challenge. As a result, kernel approximation methods have emerged as promising alternatives, but their comparison and ensemble performance is still a field of study. Some open questions include how individual methods compare against each other, and whether ensembles could benefit from certain combinations of approximations. In this paper, we evaluate four methods: Nyström, Random Fourier Features, Kernel Thinning and Neural Orthogonal Random Features (NORF). NORF is presented as a new contribution. We evaluate each method in terms of balanced accuracy, training time, and prediction diversity based on the prediction correlations. In addition, we investigate their performance in voting ensemble architectures. As a result, we observe that the best model is Nyström, not only individually but also because of its potential improvement in ensemble settings. These ensembles do not differ significantly from Kernel Support Vector Machine in performance, but they reduce training time. Moreover, NORF stands out as an alternative that does not rely on a predefined kernel and increases prediction diversityThe authors acknowledge financial support from project PID2022139856NB-I00 funded by MCIN/ AEI / 10.13039/501100011033 / FEDER, UE and project, IDEA-CM (TEC-2024/COM-89) from the Comunidad Autónoma de Madrid, from the ELLIS Unit Madrid and Cátedra UAM-IIC de Ciencia de Datos y Aprendizaje Automátic
Characterization of the nature of organic matter in carbonate rocks: Implications for geological and environmental studies
No full textOrganic matter in carbonate rocks plays a crucial role in processes such as fluid flow regulation,carbon sequestration, contaminant transport, and hydrocarbon recovery. This study employed multimodalspectroscopic techniques, including fluorescence imaging and Fourier transform infrared (FTIR) spectroscopy,to characterize the spatial distribution and spectral characteristics of organic matter in carbonate rocks bycomparing bioclastic and non‐bioclastic components. Fluorescence hyperspectral analysis revealedheterogeneous distribution within the carbonate framework. UV fluorescence appears preferentially associatedwith bioclastic grains, whereas visible fluorescence is more broadly distributed and more pronounced inreservoir samples. Variations in spectral features, including differences in the relative contributions of tyrosine‐and tryptophan‐like emission, highlight contrasts among bioclastic components such as red algae and mollusksand reveal the critical role of biominerals in tunning surface chemistry and wettability. These findings highlightthe heterogeneity and complexity of organic matter in carbonate rocks, offering insights into diagenesis, organicmatter preservation, and paleoenvironmental reconstructions with implications for rock characterization andresource management. FTIR microspectroscopy provides complementary information on organic functionalgroups and supports the heterogeneous distribution of organic matter inferred from fluorescence mapping.While these spectroscopic signatures do not provide direct molecular identification, the combined spatial andspectral observations suggest that preserved or altered organic matter contributes to variations in surfacechemistry and wettability in carbonate rocks. These results underscore the complexity of organic matterpreservation in carbonates and demonstrate the potential of fluorescence hyperspectral imaging as a frameworkfor future method validation studies addressing carbonate diagenesis, paleoenvironmental reconstruction, andreservoir characterizationWe thank the Synchrotron SOLEIL (Saint‐Aubin, France) for beamtime on theDISCO and SMIS beamlines (project#20220467
Integrated performance and techno-economic evaluation of pilot-scale Catalytic Wet Peroxide Oxidation (CWPO) for toxic cyanobacteria and cyanotoxins removal
No full textThe increasing occurrence of toxic cyanobacteria blooms in drinking water sources poses a global health risk, underscoring the need for new, economically viable, and eco-friendly treatments. Catalytic Wet Peroxide Oxidation (CWPO), using natural magnetite, has shown strong potential for degrading cyanobacteria and cyanotoxins, though scaling it up for continuous, large-scale treatment remains challenging. This study evaluated the CWPO process at pilot scale using a continuous stirred slurry tank reactor (3 L) coupled with continuous magnetite recovery to degrade microcystin-LR (MC-LR), one of the most prevalent cyanotoxin worldwide, under ambient conditions. Key operational variables (including magnetite concentration, initial H2O2 concentration, and pH) were optimized. Under optimal conditions ([Fe3O4] =8 g L 1; [H2O2]0 =12.6 mg L 1; flow rate =50 mL min 1; pH0 =3.5), the process achieved up to 90% MC-LR degradation. Simultaneous elimination of cyanobacteria (>99.9%) and 85% cyanotoxin reduction was achieved in the presence of Microcystis aeruginosa cells (50 μg L 1, measured as chlorophyll-a). A slight process intensification ([Fe3O4] =10 g L 1; [H2O2]0 =15 mg L 1) allowed increasing to 95% the cyanotoxin degradation, resulting in a fully non-toxic effluent (Daphtoxkit-F ISO standard 6341 procedure). Finally, an industrial-scale design was proposed for a Drinking Water Treatment Plant (DWTP) designed for 10,000 population equivalent, with estimated costs of 0.19 € per treated cubic meter after economical optimization. Electricity for aeration, hydrogen peroxide consumption and pH adjustment were identified as the main contributors to the overall operating cost. This approach offers a safe and sustainable, advancing innovative water treatment technologiesThis work has been supported through the project CNS2023-144453 funded by MCIN/AEI/10.13039/501100011033 and by European Union NextGenerationEU/PRTR, and thorough the project PID2022- 139063OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by ERDF A way of making Europe. D. Ortiz thanks the Spanish Ministry of Universities (MIU) for the FPU predoctoral grant (FPU19/04816). N. Lopez-Arago thanks for the FPI predoctoral grant (PRE2020–09452) funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your futur
Sustainable, QoS, and cost-aware placement of microservices on the continuum: a use case on the Internet of Medical Things
No full textDomains such as healthcare, which are intensive in contrast to user-grade domains, are increas-ingly interested to develop Internet of Things (IoT) applications to automate their critical pro-cesses, leading to the Internet of Medical Things (IoMT). IoMT applications leverage the Comput-ing Continuum infrastructure. However, for intensive IoT and IoMT applications to be feasible, their strict Quality of Service (QoS) requirements must be met, and the economic cost of their deployment must be low to ensure their business viability. Furthermore, sustainability and the reduction of the carbon footprint are currently a priority due to industrial and governmental ini-tiatives and requirements, such as Green IoT or the Sustainable Development Goals. The efforts in sustainability are aimed not only at achieving energy-efficient applications, but carbon-aware ones, aligning carbon footprint reduction with high QoS and low economic cost. While all three objectives can be achieved by strategically placing the microservices of these IoT applications, navigating the trade-offs across the three is a complex issue, calling for automated solutions that provide IoT application developers with a manageable number of Pareto-optimal microservice placements. This work presents the Many-Objective Genetic Algorithm for Microservice Place-ment (MOGAMP), which leverages evolutionary computing to assist IoT application developers in navigating the QoS, cost, and sustainability trade-off in microservice placement. In an evalua-tion with an IoMT use case, MOGAMP is shown to be scalable, up to 459.82 times faster and with a memory footprint of up to 0.37% compared to alternatives, enabling IoT application developers to explore wide, yet manageable, Pareto frontsThis work has been partially funded by the European Union under the MSCA project RENOS (contract number 101205037). Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union or the European Research Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. This work has also been partially funded by the projects TED2021-130913B-I00, PDC2022-133465-I00, PID2022-140907OB-I00, PRTR-C17.I1 and RED2022-134337-T funded by MICIU/AEI/10.13039/501100011033, the European Union “Next Generation EU/PRTR” and ERDF “A way of making Europe” as well as by the Cap4IE project (0786_CAP4ie_4_P) funded by the Interreg V-A España-Portugal (POCTEP) 2014–2020 program, by the Regional Ministry of Economy, Science and Digital Agenda of the Regional Government of Extremadura (GR21133) and the European Regional Development Fund . The authors acknowledge TU Wien Bibliothek for financial support through its open access funding progra
Integrated Multi-Organ Ultrasound
No full textIntegrated multi-organ ultrasound is increasingly used across various medical specialties. It should be performed in conjunction with history, physical examination, and other
investigations in the diagnostic process to enhance the detection of conditions in the lung, heart, and abdomen. Multi-organ ultrasound has been shown to improve
diagnostic accuracy in a sizeable portion of patients, potentially altering treatment plans. Specifically, it aids in assessing shock, sepsis, dyspnea, delirium, and in the peri operative setting, contributing to a more comprehensive patient assessment proces
Emotion regulation-focused interventions in adults with Posttraumatic Stress Disorder: A systematic review
No full textTrabajo Fin de Grado en Psicología. Curso académico 2025-2026.
Modalidad A. Ensayo teóricoEl Trastorno por Estrés Postraumático y, especialmente, el Trastorno por Estrés Postraumático Complejo se asocian a una marcada desregulación emocional. En la presente revisión sistemática se analizaron 10 ensayos controlados aleatorizados de intervenciones centradas en la regulación emocional en adultos con estos trastornos, evaluando su impacto en síntomas postraumáticos, desregulación emocional, sintomatología comórbida y el abandono y finalización del tratamiento. Los resultados indican que estas intervenciones muestran mejoras en modulación afectiva, síntomas depresivos y funcionamiento interpersonal, pero no se ha encontrado superioridad en el resto de dominios analizados. Dada la heterogeneidad de protocolos y medidas, los hallazgos requieren cautela. Se propone una aplicación flexible, priorizando este componente cuando predomine una elevada desregulación, síntomas depresivos o deterioro de las relaciones socialesPost-Traumatic Stress Disorder and, especially, Complex Post-Traumatic Stress Disorder are associated with marked emotion dysregulation. In the present systematic review, 10 randomized controlled trials of emotion regulation–focused interventions in adults with these disorders were analyzed, assessing their impact on posttraumatic symptoms, emotion dysregulation, comorbid symptomatology, and treatment dropout and completion. The results indicate that these interventions show improvements in affect modulation, depressive symptoms, and interpersonal functioning, but no superiority was found in the remaining domains analyzed. Given the heterogeneity of protocols and measures, the findings should be interpreted with caution. A flexible application is proposed, prioritizing this component when pronounced dysregulation, depressive symptoms, or impairment in social relationships predominate
Reference values for near fiber EMG for the diagnosis of neuromuscular disorders
No full textObjective: Quantitative EMG improves diagnostic accuracy and objectivity of EMG examinations. Decomposition based Quantitative EMG (DQEMG) is a high-quality method to quantify motor unit potential (MUP) train features,
and includes novel algorithms to extract near-fiber EMG (NF-EMG) features related to motor unit (MU) electrophysiological temporal structure and instability. This study characterized reference values for NF-EMG features in healthy muscles.
Methods: EMG signals were acquired using concentric needle electrodes from seven commonly examined muscles (330 studies, 196 patients) following standard protocols. DQEMG software extracted MUP trains and calculated both conventional MUP and NF-EMG features. Threshold-of-normality values were defined based on the 2.5 and 97.5 percentiles. For each NF-EMG feature, individual and mean upper and lower thresholds, as well as maximum incidence of abnormal values in healthy muscles, were determined.
Results: NF-EMG feature thresholds-of-normality were consistent, and value distributions showed low intersubject and inter-muscle variability. The concurrence of increased temporal dispersion and instability in a healthy population was minimal.
Conclusions: NF-EMG temporal structure and instability features, extracted from conventional EMG signals, are tightly clustered in healthy muscles and could help detect early neurophysiological changes before conventional MUP features exceed threshold-of-normality values. Thus, NF-EMG could be a valuable tool for diagnosing neuromuscular disordersThis work was partially funded by the Natural Science and Engineering Research Council of Canada (NSERC Discovery Grant WO 50503–10270
Catalytic wet peroxide oxidation (CWPO) of widespread cyanotoxins: Degradation pathways and toxicity assessment
No full textThe widespread occurrence of cyanotoxins in water bodies presents a significant health risk due to their high toxicity and persistence in the environment. Exposure to these toxins can lead to severe health issues, from gastrointestinal distress to organ failure, underscoring the urgent need for advanced water treatment methods. Catalytic Wet Peroxide Oxidation (CWPO) has proven effective for cyanotoxin removal; however, the specific degradation pathways during CWPO remain unclear. This study elucidates the possible degradation pathways of some of the most globally prevalent cyanotoxins, including microcystin-LR (MC-LR) and cylindrospermopsin (CYN), through CWPO using magnetite as a catalyst. These pathways involve hydroxylation, dehydrogenation, decarboxylation, functional group substitution, and ring opening, identifying new degradation by-products. The evolution of ecotoxicity during CWPO was also examined, revealing an initial increase in effluent toxicity under sub-stoichiometric H 2 O 2 conditions, but eventually declines below the toxicity of the original cyanotoxins. Raising the oxidant concentration to stoichiometric levels efficiently eliminates cyanotoxins, yielding primarily short-chain organic acids in a completely non-toxic effluent. These findings are critical for optimizing CWPO as a safe, efficient, and sustainable approach for treating cyanotoxins in water, marking important progress towards cost-effective and environmentally friendly water treatment solutionsThis work has been supported through the project CNS2023–144453 funded by MCIN/AEI/10.13039/501100011033 and by European Union NextGenerationEU/PRTR, and thorough the project PID2022–139063OB-I00 funded by MCIN/AEI/10.13039/ 501100011033 and by ERDF A way of making Europe. D. Ortiz thanks the Spanish Ministry of Universities (MIU) for the FPU predoctoral grant (FPU19/04816
Estudio de la adherencia bacteriana y la formación de biofilm de Staphylococcus spp. sobre la superficie de una aleación de CoCrMo anodizada
No full textTesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Medicina Preventiva y Salud Pública y Microbiología. Fecha de Lectura: 25-06-2025Esta Tesis tiene embargado el acceso al texto completo hasta el 25-12-2026El fracaso de las prótesis articulares constituye un problema clínico de gran relevancia, siendo el aflojamiento aséptico y las infecciones periprotésicas las principales causas de recambio quirúrgico. La selección del biomaterial y la modificación de sus propiedades superficiales desempeñan un papel fundamental en la mejora de la osteointegración y la reducción del riesgo de colonización bacteriana.
En este contexto, la presente investigación analizó, en primer lugar, el comportamiento de dos aleaciones metálicas de uso común en implantes ortopédicos, titanio-aluminiovanadio (Ti6Al4V) y cobalto-cromo-molibdeno (CoCrMo), comparando su interacción con Staphylococcus aureus y Staphylococcus epidermidis, las especies bacterianas más frecuentemente implicadas en la etiología de la infección periprotésica.
En segundo lugar, se investigó el impacto de la anodización de la superficie del CoCrMo como estrategia para modificar sus propiedades fisicoquímicas y reducir la adhesión bacteriana. Los resultados mostraron que la anodización indujo una reducción significativa en la adhesión y formación de biofilm de S. aureus y S. epidermidis en comparación con la superficie pulida mecánicamente. Mediante microscopía electrónica de barrido (SEM) y microscopía confocal de barrido láser (CLSM), se observó que esta disminución en las unidades formadoras de colonias adheridas a la superficie se correlacionaba con una menor cantidad de proteínas y ADN extracelular en el biofilm, lo que resultó en una estructura menos cohesiva. Además, los agregados presentes en los sobrenadantes tras la incubación con la superficie anodizada mostraron, en ambas especies, sustanciales diferencias morfológicas. Asimismo, se analizó la liberación de cationes metálicos desde la superficie del CoCrMo. Se encontró que la superficie anodizada liberó una mayor cantidad de Cr, Co y Mo en comparación con la superficie pulida mecánicamente. Se demostró que la presencia de estos cationes interfiere tanto en la adhesión como en la formación de biopelícula por parte de ambas especies bacterianas. Además, el estudio de las proteínas adsorbidas desde el plasma reveló un patrón distinto en las dos superficies estudiadas.
En un tercer apartado, se evaluó la influencia del método de fabricación en la adherencia bacteriana, comparando CoCrMo fabricado mediante sinterizado directo de metal por láser (DMLS) con su versión convencional obtenida por forja. Los resultados indicaron que la aleación fabricada mediante DMLS disminuyó la adherencia bacteriana en comparación con la aleación obtenida por el método convencionalEste trabajo ha sido financiado a través del Proyecto del Ministerio de Economía, Industria y Competitividad (MAT2017-86163-C2).
Paul Stoodley fue financiado a través de la NIH R01 GM12443
Materiales estructurados para aplicaciones fotónicas y fonónicas
No full textTesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física de Materiales. Fecha de Lectura: 06-06-2025Esta Tesis tiene embargado el acceso al texto completo hasta el 06-12-2026Esta tesis se centra en el desarrollo de materiales fotónicos y fonónicos avanzados, con especial énfasis en sus aplicaciones en sistemas multifuncionales.
En la primera parte, se aborda la fabricación y el análisis de estructuras ordenadas autoensambladas. Se ofrece una visión detallada de las distintas técnicas empleadas en la construcción de estas estructuras y se investigan protocolos de postratamiento para la producción de monocapas adaptadas a aplicaciones optomecánicas. A continuación, se exploran las propiedades optomecánicas de monocapas de nanopartículas de poliestireno. Mediante cálculos computacionales con un programa comercial de elementos finitos, se demuestra la existencia de un bandgap mecánico completo en el rango de los gigahercios. La caracterización experimental de estas monocapas se lleva a cabo mediante espectroscopia Brillouin y técnicas de excitación y detección, evidenciando una alta concordancia entre los modos observados experimentalmente y los obtenidos en los cálculos computacionales, así como el efecto de hibridación inducido por el substrato.
La segunda parte se enfoca en el diseño y control de estructuras desordenadas, específicamente en sistemas láser estocásticos. Se describe en detalle la fabricación de estructuras con ganancia para láseres estocásticos y se analiza el comportamiento de sus modos láser. Entre los parámetros estudiados se incluyen la longitud de la cavidad, el tiempo del pulso de bombeo, la anchura y la energía de la línea de bombeo. Además, se investigan aspectos clave en el acoplamiento de distintos láseres aleatorios. Para concluir, se presenta un análisis en profundidad de la teoría de modos acoplados aplicada a estos sistemas. Se establece la relación entre la densidad de modos y la longitud de la cavidad, respaldando los hallazgos experimentales sobre el control de la persistencia espectral. Asimismo, se evalúa la aplicabilidad del parámetro de solapamiento de intensidad y la ruptura de simetría de réplica en sistemas láser aleatorios, un concepto originalmente desarrollado para el estudio de vidrios de espín. En este análisis, se combinan enfoques computacionales y experimentale