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Ítem Enhancing Proton Therapy Planning Through Uncertainty Quantification Maps(Sociedad Española de Ingeniería Biomédica (SEIB), 2024-12-02) Hernandez-Rubia, Javier; Rodriguez-Gonzalez, Blanca; Vera-Sanchez, Juan Antonio; Mazal, Alejandro; Malpica, Norberto; Torrado-Carvajal, Ángel; Rodriguez-Vila, BorjaThis project discusses the evaluation of a state-of-the-art deep learning-based model for improving the efficacy of the preparation of a proton therapy treatment. This technique is known due to its precision in targeting tumoral areas, which requires a thorough planning to minimize damage of healthy surrounding tissues. The importance of Artificial Intelligence in medical imaging led to the development of the nnUNet model, considered the gold standard for image segmentation. Thus, this work focuses on the study of this model to better understand the process of automatic segmentation of critical organs in CT examinations compared to a ground truth of segmentation by radiation oncologists, by performing a full study on the results. Initial evaluations were conducted, ending up with a Dice Coefficient of 0.810 and Hausdorff Distance of 3.381mm, which led to an uncertainty quantification study to assess the robustness of the model with the Test Time Augmentation method. This study concluded that adaptive architectures are clinically more effective than complex deep learning models. Due to the robustness nature of the nnUNet model, its usability for proton therapy planning is proven.Ítem Multilayer Models of Random Sequences: Representability and Inference via Nonlinear Population Monte Carlo(IEEE, 2019) Míguez, Joaquín; Lacasa, Lucas; Martínez-Ordoñez, José A.; Mariño, Inés P.We investigate a class of dynamical models with a multilayer structure for the representation of discrete-time sequences. Each layer is a first-order, discrete-time Markov process, either on a discrete state space (i.e., a Markov chain) or on a general state space. The transition kernel for each layer is different (hence it yields different stochastic dynamics) and at each time there is a single active layer. The active layers are selected over time according to a first-order Markov chain. This simple description includes many types of interacting multiple models, of interest in target tracking applications. It also fits many real-world systems that display a variety of dynamical patterns over time without any observable switching mechanism (examples abound in financial time series). In this paper we show that the family of multilayer models described above can represent a broad class of random sequences, including Markov chains of order M >1 on discrete spaces or auto-regressive process (again, of order M > 1) on general state spaces. We also propose a general nonlinear population Monte Carlo scheme that can be employed for model selection and model inference. Numerical examples are given for the case of multilayer models with discrete observations.Ítem Detecting Narcissist Dark Triad Psychological Traits from Twitter(SciTePress, 2022) Haz, Lídice; Rodríguez-García, Miguel Ángel; Fernández, AlbertoThe fundamental basis of human behavior is personality. This human characteristic influences the tastes and preferences of individuals and the way they interact and communicate with each other. Nowadays, individuals express their feelings, opinions, and ideas to the world by using digital communication platforms such as social media. In recent years, several studies have proposed different models that apply Artificial Intelligence techniques to identify personality traits based mainly on the Big 5 Personality Model and the three subpersonalities of the Dark Triad through the linguistic analysis of their comments online. In this work, we present a study about identifying narcissist dark triad psychological traits. We propose two Machine Learning models to analyze users’ behavior in social media. Concretely, we develop a Support Vector Machine and Naïve Bayes method to classify the comments as having non-narcissist or narcissist traits. To train and test the developed method, we have employed NLP techniques to process comments from Twitter and created a manual dataset. Three different techniques have been designed and applied to label each tweet and comment. Then, we conducted several evaluations in which both models reached promising results.Ítem El concepto no neolítico del fenómjeno megalítico madrileño : Entretérminos y Las Vegas de Samburiel(Museo Arqueológico de Alicante, MARQ, 2006) Jiménez Guijarro, Jesús MaríaEn esta comunicación se presentan algunas reflexiones acerca del fenómeno megalítico de la Comunidad de Madrid, así como su filiación cronológica y cultural. En este caso, el estudios de diferentes enclaves nos permite reflexionar acerca de la adscripción no neolítica de sus materiales. Esto nos permite alcanzar hipótesis relacionadas directamente con la puesta en marcha de modelos de colonización de las áreas serranas donde abundan los recursos minerales metálicos, la presencia de yacimientos fortificados en altura y sobre todo un horizonte cultural calcolítico.Ítem Caracterización de las cerámicas impresas cardiales y pseudocardiales de la Cuenca del Tajo(Museo Arqueológico de Alicante, MARQ, 2008-01-01) Jiménez Guijarro, Jesús María; Rojas Rodríguez-Malo, Juan ManuelLa localización, en contextos arqueológicos neolíticos bien controlados de la Meseta española, de un creciente número de cerámicas decoradas con impresiones de aspecto cardial plantea la necesidad de afinar no sólo en la cuestión de las dataciones radiocarbónicas, sino sobre todo en la caracterización estricta del material arqueológico. A este respecto hemos realizado un exhaustivo estudio experimental de las impresiones de estilo cardial y pseudo-cardial presentes en contextos de la Península Ibérica y Francia dirigido a la obtención de un primer corpus comparativo. Este estudio señala la dificultad inherente a la separación estricta de las impresiones cardiales y pseudocardiales y plantea la necesidad de que sean tratadas como integrantes de un mismo conjunto cultural.Ítem Actas de las Jornadas: Nuevas realidades. Nuevas perspectivas de necesario estudio(Universidad Rey Juan Carlos, 2024-12-28) Carreras Presencio, Ana IsabelÍtem Joint Inference of Multiple Graphs with Hidden Variables from Stationary Graph Signals(IEEE, 2022) Rey, Samuel; Buciulea, Andrei; Navarro, Madeline; Segarra, Santiago; Marques, Antonio G.Learning graphs from sets of nodal observations represents a prominent problem formally known as graph topology inference. However, current approaches are limited by typically focusing on inferring single networks, and they assume that observations from all nodes are available. First, many contemporary setups involve multiple related networks, and second, it is often the case that only a subset of nodes is observed while the rest remain hidden. Motivated by these facts, we introduce a joint graph topology inference method that models the influence of the hidden variables. Under the assumptions that the observed signals are stationary on the sought graphs and the graphs are closely related, the joint estimation of multiple networks allows us to exploit such relationships to improve the quality of the learned graphs. Moreover, we confront the challenging problem of modeling the influence of the hidden nodes to minimize their detrimental effect. To obtain an amenable approach, we take advantage of the particular structure of the setup at hand and leverage the similarity between the different graphs, which affects both the observed and the hidden nodes. To test the proposed method, numerical simulations over synthetic and real-world graphs are providedÍtem Aproximación cronológica del arte esquemático en las estribaciones del Sistema Central(Museo Arqueológico de Alicante - MARQ, 2008) Jiménez Guijarro, Jesús MaríaSe presenta una reflexión acerca de la aproximación cronológica del arte esquemático de las estribaciones del Sistema Central basándonos en la existencia de yacimientos arqueológicos asociados que presenten materiales que permitan afinar algo respecto a su cronología. Este trabajo plantea la posibilidad de que el origen del arte esquemático de este sector esté ligado a momentos avanzados del Neolítico Antiguo Evolucionado (NAIB). Se plantea la existencia de disimetrías entre la presencia de enclaves neolíticos –de funcionalidad habitacional y sepulcral– y la ubicación espacial de los paneles decorados.Ítem An Ontology for Value Awareness Engineering(SciTePress, 2024) Holgado-Sánchez, Andrés; Billhardt, Holger; Ossowski, Sascha; Fernández, AlbertoThe field of value awareness engineering claims that intelligent software agents should be endowed with a set of capabilities related to human values, enabling them to identify value-aligned outcomes and, ultimately, to choose their behaviour in value-aware manner. In this work we develop an ontology that links many of the models and concepts that have been proposed in relation to computational value awareness, so as to be able to formalize in a common language the various heterogeneous research proposals in the field. Specifically, we illustrate its capability for describing multi-agent systems from the value-awareness engineering perspective through several case studies grounded in concrete approaches from literature. The ontology, implemented in OWL and extended with SWRL rules, is evaluated following scenarios of the NeOn Methodology and is interconnected with relevant ontologies in the Semantic Web.Ítem Effects of high-definition transcranial direct current stimulation on conflict resolution: insights from behavioral, EEG and phenomenological measures(Elsevier, 2024-10) Sanabria, Daniel; Holgado, Darías; Martínez-Pérez, Víctor; Martín-Arévalo, Elisa; Bekinschtein, Tristán A.; Fernández-del-Olmo, Miguel Á.; Luque-Casado, AntonioThe efficacy of non-invasive brain stimulation techniques in enhancing conflict resolution abilities remains a contentious issue in cognitive neuroscience. To contribute further to this topic, we employed a sham-controlled between-groups design to investigate the cognitive, phenomenological, and physiological effects of anodal and cathodal high-definition transcranial direct current stimulation (HD-tDCS) targeting the bilateral dorsolateral prefrontal cortex (DLPFC) during conflict resolution tasks. Sixty participants completed a 30-minute flanker task, a widely used measure of cognitive control and conflict processing. Electroencephalography (EEG) activity was recorded at four time points: at rest, prior to task commencement, during task execution before tDCS administration, during task execution after tDCS administration, and post-task rest. Additionally, a novel method called temporal experience tracing (TET) was employed to retrospectively evaluate participants' subjective experiences throughout the experimental procedure. TET involved participants reporting the intensity of predefined experiential dimensions along a temporal axis. Findings revealed no statistically significant differences between tDCS groups in reaction time, accuracy data, drift diffusion modeling, or EEG frequency power analyses. Analysis of TET data unveiled an anticipated temporal pattern across all subjective dimensions, e.g., an increase in mind-wandering over time. Notably, significant differences between tDCS groups emerged in the "fed-up" and "boredom" dimensions, indicating varied subjective experiences influenced by stimulation conditions. Furthermore, Lempel-Ziv analysis demonstrated that EEG complexity escalated from the pre-task to post-task periods to a greater extent in the cathodal and sham conditions compared to the anodal condition. In summary, this study provides valuable insights into the nuanced effects of tDCS during conflict resolution tasks. Notably, the employment of the novel TET methodology allowed for a comprehensive assessment of participants' subjective experiences throughout the experimental procedure. These findings contribute to advancing our understanding of the cognitive and phenomenological effects of tDCS and underscore the importance of integrating innovative methodologies in neurostimulation research.Ítem The impact of prefrontal tDCS on conflict resolution and its phenomenological dynamics: a HD-tDCS/EEG randomized sham-controlled novel approach based on Drift Diffusion Modeling(Elsevier, 2023-10) Martínez-Pérez, Víctor; Martín-Arévalo, Elisa; Fuentes, Luis; Fernández-del-Olmo, Miguel Á.; Sanabria, Daniel; Luque-Casado, AntonioWhen humans are faced with conflict resolution tasks, performance is usually impaired. The effects of applying non-invasive brain stimulation techniques on conflict resolution performance is still an open question under debate. In this study we will address this issue by assessing the cognitive and physiological effects of applying anodal and cathodal high-definition transcranial direct current stimulation (HD-tDCS) over bilateral dorsolateral prefrontal cortex (DLPFC) on conflict resolution by using a 30-min flanker task. Moreover, the effects of the stimulation on phenomenological constructs such as mind-wandering, boredom, perceived cognitive effort and arousal over the course of the task will be addressed. In a pre-registered, randomized, sham-controlled, parallel study, we will assign participants to one of the three groups of stimulation: anodal, cathodal, and sham. A pre-post resting state EEG and the task-related oscillatory activity during the first and last 6-min temporal blocks of the task will be measured. Stimulation will be applied online from the second to the fourth block of trials (18 minutes). Right after, participants will be asked to report their temporal experience tracing (TET), a method that captures relevant aspects of their phenomenological experiences over a continuous period of time by drawing their headway in the task between two axes. Behavioral data will be analyzed by applying a drift diffusion modelling that enables statistical separation of different components of a speeded binary decision process. This novel approach will allow us to get a more thorough understanding of cognitive processes and electrophysiological mechanisms underlying the effects of cathodal and anodal stimulation on conflict resolution. As far as we know, this will be the most comprehensive piece of work within this research topic.Ítem The impact of prefrontal high-definition transcranial direct current stimulation (HD-tDCS) on conflict resolution and its phenomenological dynamics(2023-09) Martínez-Pérez, Víctor; Alameda, Clara; Martín-Arévalo, Elisa; Fuentes, Luis; Bekinschtein, Tristán; Fernández-del-Olmo, Miguel A.; Sanabria, Daniel; Luque-Casado, AntonioThe effects of applying non-invasive brain stimulation techniques on conflict resolution performance is still an open question. Here we will address this issue by assessing the cognitive and physiological effects of applying anodal and cathodal HD-tDCS over DLPFC on conflict resolution by using a 30' flanker task. Moreover, the effects of the stimulation on phenomenological dynamics over the course of the task will be addressed. In a pre-registered, randomized, sham-controlled, parallel study, we will assign participants to one of the 3 groups of stimulation: anodal, cathodal, sham. A pre-post resting state EEG and the task-related oscillatory activity during the first and last 6' temporal blocks of the task will be measured. Stimulation will be applied online from the second to the fourth block of trials (18'). Right after, participants will be asked to report their temporal experience tracing. Behavioral data will be analyzed by applying a drift diffusion modelling. This novel approach will allow us to get a more thorough understanding of cognitive processes and electrophysiological mechanisms underlying the effects of stimulation on conflict resolution. As far as we know, this will be the most comprehensive work on this topicÍtem Investigaciones sobre el desarrollo de la competencia oral en distintas etapas educativas(2024-12-20) Alvarado, Jesús; Cabellos, Beatriz; Zarza, María Teresa; Ondé, Daniel; Garza, Priscila; Quezada, VerónicaÍtem Prácticas docentes en el uso de las TIC: El efecto de las actitudes y las condiciones facilitadoras de los centros(ASUNIVEP, 2023-12-20) Cabellos, BeatrizÍtem Análisis de la competencia de comunicación oral en secundaria y universidad: Diferencias por género, entorno, nivel lector y otras variables asociadas(ASUNIVEP, 2023-12-20) Alvarado, Jesús; Cabellos, Beatriz; Aparicio, Marta Evelia; Ondé, Daniel; Jiménez, Virginia; Delgado, Cynthia MaríaÍtem Evaluación Automatizada de Textos mediante Inteligencia Artificial Generativa y Procesamiento del Lenguaje Natural(Aemcco, 2024-09-20) Cabellos, Beatriz; Jorge-Botana, Guillermo; Alvarado, JesúsÍtem ¿Cómo el uso de las TIC en las prácticas docentes ha cambiado desde el confinamiento?(ASUNIVEP, 2023-12-20) Cabellos, BeatrizÍtem Teachers’ attitudes about the use of Generative Artificial Intelligence in classrooms(International Union of Psychological Science, 2024-08-20) Cabellos, Beatriz; De Aldama, Carlos; Pozo, Juan IgnacioÍtem The potential of dialogue to promote moral activation using video games(International Union of Psychological Science, 2024-08-20) Cabellos, Beatriz; Pozo, Juan IgnacioÍtem Las redes de delincuencia organizada(Dykinson, 2006) Ropero Carrasco, JuliaIntroducción a los conceptos de organización y grupo criminal y análisis de política criminal sobre la expansión de la delincuencia organizada