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Multidimensional polynomial phase estimation
No full textAn estimation method is presented for polynomial phase signals, i.e., those adopting the form of a complex exponential whose phase is polynomial in its indices. Transcending the scope of existing techniques, the proposed estimator can handle an arbitrary number of dimensions and an arbitrary set of polynomial degrees along each dimension; the only requirement is that the number of observations per dimension exceeds the highest degree thereon. Embodied by a highly compact sequential algorithm, this estimator is efficient at high signal-to-noise ratios (SNRs), exhibiting a computational complexity that is strictly linear in the number of observations and at most quadratic in the number of polynomial terms. To reinforce the performance at low and medium SNRs, where any phase estimator is bound to be hampered by the inherent ambiguity caused by phase wrappings, suitable functionalities are incorporated and shown to be highly effective.The work of Heedong Do and Namyoon Lee was supported by the National Research Foundation of Korea (NRF) under Grant RS-2023-00208552 and Grant RS-2022-NR070834, funded by the Korea government (MSIT). The work of Angel Lozano was supported in part by the Maria de Maeztu Units of Excellence Programme under Grant CEX2021-001195-M and in part by ICREA
Pensamiento crítico y alfabetización en IA: evaluando sistemas de inteligencia artificial en procesos de enseñanza/aprendizaje
No full textEn este informe se presenta el resultado del trabajo realizado en el marco de una asignatura de prácticas académicas en el Máster Universitario en Investigación en Comunicación de la Universidad Pompeu Fabra. Se presenta el resultado del análisis de seis sistemas de inteligencia artificial generativa especializados en usos académicos. Se presenta el método de análisis y los esquemas de extracción de datos así como los resultados obtenidos. Se trata de un proceso de alfabetización en IA y de aplicación del pensamiento crítico en el uso de sistemas de IA como parte de una asignatura de participación en proyectos de estudiantes de un máster universitario. Se presentan así mismo los datos de desarrollo de la experiencia docente a modo de estudio de caso para interesados en procesos de enseñanza aprendizaje donde interviene el uso monitorizado de sistemas de inteligencia artificial en la academia.This report presents the results of the work carried out within the framework of an academic internship subject in the Master's Degree in Communication Research at Pompeu Fabra University. This report presents the results of the analysis of six generative artificial intelligence systems specialized in academic applications. The analysis method and data extraction schemes are presented, as well as the results obtained. This work presents a process of AI literacy and the application of critical thinking in the use of AI systems as part of a course involving participation in student projects in a master's degree program. Data on the development of the teaching experience are also presented as a case study for those interested in teaching-learning processes involving the monitored use of artificial intelligence systems in academia.Este trabajo forma parte de las actividades en transferencia e innovación docente del proyecto "Parámetros y estrategias para incrementar la relevancia de los medios y la comunicación digital en la sociedad: curación, visualización y visibilidad (CUVICOM)” financiado por MICIU/AEI/PID2021-123579OB-I00 y por “FEDER/UE”
The glutathione system maintains the thiol redox balance in the mitochondria of fission yeast
No full textThe thioredoxin and glutathione (GSH)-glutaredoxin electron donor pathways provide a reducing environment to the cell and maintain homeostasis of numerous redox reactions. The abundant tripeptide GSH has multiple roles, including redox buffering, detoxification, peroxide scavenging and iron-sulfur cluster assembly. Glutathione reductase, Pgr1 in fission yeast, maintains glutathione reduced, and it is essential in most organisms. Cells lacking Pgr1 exhibit severe pleiotropic defects. We used multiple approaches to unravel the compartment-specific roles of Pgr1. Our findings confirmed that Pgr1 had dual cytosolic and mitochondrial localization. Mitochondrial homeostasis was severely impaired in Δpgr1 cells and most of these defects were restored by expression of an exclusively mitochondrial Pgr1 isoform. As expected, the cytosol of Δpgr1 cells showed low ratio of reduced-to-oxidized glutathione. However, this did not significantly affect peroxiredoxin-dependent hydrogen peroxide scavenging, suggesting a minimal role, if any, of GSH in cytosolic thiol reduction. The transcriptome of Δpgr1 cells revealed signatures of oxidative stress and iron deprivation, suggesting that the GSH-containing sensor of iron starvation, the glutaredoxin Grx4, is also a sensor of GSH oxidation. In the mitochondria, Pgr1 not only provided the GSH electron donor for the glutaredoxin-based pathway but also recycled mitochondrial Trx2, thereby contributing to thiol redox homeostasis in the matrix. In conclusion, glutathione reductase is essential for maintaining a balanced redox environment in the mitochondria by recycling Trx2, Grx2 and the GSH-containing Grx5, and therefore contributes to the processes of iron-sulfur cluster assembly and respiration, while controlling Grx4 dynamics in the cytosol.This work is supported by grant PID2021-122837-NB-I00 to E.H., funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”, by the “European Union”. The Oxidative Stress and Cell Cycle group is also supported by Generalitat de Catalunya (Spain) (2021-SGR-00007) and by Excellence Unit « María de Maeztu » Grant CEX2018-000792-M funded by MCIN/AEI/10.13039/501100011033. E.H. is recipient of an ICREA Academia Award (Generalitat de Catalunya, Spain). L.C. was recipient of a FPI fellowship from the Ministerio de Economía y Competitividad (Spain)
Occupational exposure to radiofrequency electromagnetic fields and brain tumor risk: Application of the INTEROCC job-exposure matrix
No full textRadiofrequency electromagnetic fields (RF-EMF, 100 kHz to 300 GHz) are classified by IARC as possibly carcinogenic to humans (Group 2B). This study evaluates the potential association between occupational RF-EMF exposure and brain tumor risk, utilizing for the first time, a RF-EMF job-exposure matrix (RF-JEM) developed in the multi-country INTEROCC case-control study. Cumulative and time-weighted average (TWA) occupational RF-EMF exposures were estimated for study participants based on lifetime job histories linked to the RF-JEM using three different methods: (1) by considering RF-EMF intensity among all exposed jobs, (2) by considering RF-EMF intensity among jobs with an exposure prevalence ≥ the median exposure prevalence of all exposed jobs, and (3) by considering RF-EMF intensity of jobs of participants who reported RF-EMF source use. Stratified conditional logistic regression models were used, considering various lag periods and exposure time windows defined a priori. Generally, no clear associations were found for glioma or meningioma risk. However, some statistically significant positive associations were observed including in the highest exposure categories for glioma for cumulative and TWA exposure in the 1- to 4-year time window for electric fields (E) in the first JEM application method (odds ratios [ORs] = 1.36, 95% confidence interval [95% CI] 1.08, 1.72 and 1.27, 95% CI 1.01, 1.59, respectively), as well as for meningioma for cumulative exposure in the 5- to 9-year time window for electric fields (E) in the third JEM application method (OR = 2.30, 95% CI 1.11, 4.78). We did not identify convincing associations between occupational RF-EMF exposure and risk of glioma or meningioma
Spatial data science approaches to predict environmental and socioeconomic health determinants
No full textAquesta tesi, organitzada en tres articles, proposa avenços metodològics en els processos de predicció espacial utilitzats per a exposicions ambientals i socioeconòmiques.
El primer estudi prediu la temperatura i quatre contaminants atmosfèrics a alta resolució espaciotemporal a Catalunya. Inclou innovacions com l’ús de dades de TROPOMI, l’estimació de la incertesa en les prediccions i mètodes d’explicabilitat per validar les associacions.
El segon estudi investiga la inclusió de proxies espacials, com ara coordenades i distàncies, com a predictors en models random forest. En una simulació i dos casos pràctics, concloem que aquestes variables no són sempre beneficioses i identifiquem models alternatius.
El tercer estudi prediu la posició socioeconòmica de les llars en zones semirurals de Moçambic, utilitzant un conjunt de dades multimodal format per imatges per satèl·lit i de les llars, i combinant mètodes d’aprenentatge profund i automàtic seguit d’anàlisis d’explicabilitat.
Aquesta tesi contribueix a la literatura suggerint metodologies per obtenir estimacions d’exposició més precises, transparents, eficients i informatives.Esta tesis, organizada en tres artículos, propone avances metodológicos en los procesos de predicción espacial utilizados para exposiciones ambientales y socioeconómicas.
El primer estudio predice la temperatura y cuatro contaminantes atmosféricos con alta resolución espaciotemporal en Cataluña. Incluye innovaciones como el uso de datos de TROPOMI, la estimación de la incertidumbre en las predicciones y métodos de explicabilidad para validar las asociaciones.
El segundo estudio investiga la inclusión de proxies espaciales, como coordenadas y distancias, como predictores en modelos random forest. Mediante una simulación y dos casos prácticos, concluimos que estas variables no siempre son beneficiosas e identificamos modelos alternativos.
El tercer estudio predice la posición socioeconómica de los hogares en zonas semirrurales de Mozambique, utilizando un conjunto de datos multimodal formado por imágenes satelitales y de los hogares, y combinando métodos de aprendizaje profundo y automático seguidos de análisis de explicabilidad.
Esta tesis contribuye a la literatura sugiriendo metodologías para obtener estimaciones de exposición más precisas, transparentes, eficientes e informativas.Spatial prediction workflows are key for assessing health determinants in epidemiology. This thesis, comprising three manuscripts, advances spatial prediction pipelines for environmental and socioeconomic exposures.
The first study predicted temperature and four air pollutants in Catalonia using a multi-exposure framework. Innovations include the use of TROPOMI data, a remote sensing gap-filling evaluation, the estimation of prediction uncertainty, and explainable machine learning to verify associations.
The second study investigated spatial proxies (e.g., coordinates and distances) in random forest models. Through simulations and case studies, we found that spatial proxies are not always beneficial, providing insights into their suitability and alternatives.
The third study predicted household socioeconomic measures in semi-rural Mozambique using satellite and household imagery. A deep and machine learning pipeline, combined with explainability analyses, revealed clear socioeconomic patterns.
This thesis enhances spatial predictions by proposing methodologies for more accurate, transparent, and informative exposure estimates.Universitat Pompeu Fabra. Doctorat en Biomedicin
Residential greenspace and lung function throughout childhood and adolescence in five European birth cohorts. A CADSET initiative
No full textWhether greenspace affects lung function is unclear. We explored associations between the level of greenness or presence of urban green space near the home with lung function measures taken repeatedly during childhood and adolescence in five European birth cohorts. Lung function was measured by spirometry between six and 22 years (2-3 times), and 9,206 participants from BAMSE (Sweden), GINI/LISA South and GINI/LISA North (Germany), PIAMA (The Netherlands) and INMA (Spain) contributed at least one lung function measurement. The mean Normalized Difference Vegetation Index (NDVI) in a 300 m buffer and presence of urban green space within a 300 m buffer (yes/no) were estimated at the home address at the time of each spirometry measurement. Cohort-specific associations were assessed using adjusted linear mixed models and combined in a random-effects meta-analysis. Residential greenness was not associated with forced expiratory volume in one second (FEV1), forced vital capacity (FVC) or FEV1/FVC in the meta-analysis (2.3 ml [-3.2, 7.9], 6.2 ml [-3.4, 15.7] and -0.1 [-0.3, 0.1] per 0.1 increase in NDVI, respectively), nor was having a nearby urban green space (-8.6 ml [-22.3, 5.0], -7.6 ml [-24.7, 9.4] and 0.0 [-0.4, 0.3], respectively). Heterogeneity was low to moderate (I2 = 0 -39 %). Asthma, atopy, air pollution, sex, socioeconomic status and urbanization did not modify the null associations. Using repeated data from five large independent European birth cohorts, we did not find associations between vegetation levels around the home or the presence of an urban green space and lung function levels during childhood and adolescence.EF is supported by the Imperial College Research Fellowship. MS has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 949906)
Immunotherapeutic strategies for HIV cure: advancements in the characterisation and development of novel immune checkpoints therapeutics for combinatorial HIV1 immune interventions
No full textHuman Immunodeficiency Virus Type 1 (HIV-1) remains a global pandemic requiring the development of curative strategies due to the limitations of current antiretroviral treatments (ART). This thesis focuses on the need for immunotherapeutic strategies to achieve HIV-1 cure, particularly those enhancing immune responses via the blockade of inhibitory receptor pathways.
This thesis explores the enhancement of vaccine-induced HIV-1-specific CD8 T-cell responses by immune checkpoint blockade in people with HIV-1 (PWH) early treated and vaccinated. Our findings demonstrate a significant increase in vaccine-induced CD8 T-cell responses by αPD-1. Furthermore, our results propose using basal PD-1 expression and a cytokine signature as potential biomarkers for stratification. Additionally, we propose the combination of αPD-1 and αTIM-3 to reinvigorate CD8 T-cell responses in PWH on long-term ART.
In addition, this thesis develops soluble inhibitory receptors (sIRs) targeting the TIGIT/CD155 axis for HIV-1 cure. Our in vitro studies characterised binding and affinity to CD155 and the recovery of T-cell signalling by the dimeric sIR prototypes. Moreover, administering dimeric sIR prototypes in mice is safe and presents a good pharmacokinetic profile. Moreover, a proof-of-concept toxicity and efficacy study in a chronic LMCV infection model provides evidence of a reduction for the dimeric effector sIR prototype of immune toxicity induced by immune checkpoint blockade (ICB), leading to decreased viral persistence. Notably, dimeric effector sIR prototype combined with ICB enhances degranulation in TCR-stimulated CD8 T cells. These results support further preclinical development of effector sIR prototypes in humanised mouse models.El Virus de Inmunodeficiencia Humana Tipo 1 (VIH-1) sigue siendo una pandemia global que requiere el desarrollo de estrategias curativas debido a las limitaciones de los tratamientos antirretrovirales actuales (ART). Esta tesis se centra en la necesidad de estrategias inmunoterapéuticas para lograr la cura del VIH-1, especialmente aquellas que potencian las respuestas inmunitarias mediante el bloqueo de las vías de receptores inhibitorios.
Esta tesis explora el aumento de las respuestas de células T CD8 HIV-1 específicas inducidas por vacunas utilizando el bloqueo de puntos de control inmunitario en personas con VIH-1 (PWH) tratadas tempranamente y vacunadas. Nuestros hallazgos demuestran un aumento significativo en las respuestas de células T CD8 inducidas por vacunas mediante αPD-1. Además, nuestros resultados proponen el uso de la expresión basal de PD-1 y un perfil de 13 citocinas como biomarcadores potenciales para la estratificación y la evaluación de la capacidad de respuesta del paciente al uso de αPD-1. Asimismo, proponemos la combinación de αPD-1 y αTIM-3 para reactivar las respuestas de células T CD8 en PWH en ART de largo plazo.
Además, esta tesis desarrolla receptores inhibitorios solubles (sIRs) que apuntan al eje TIGIT/CD155 para la cura del VIH-1. Nuestros estudios in vitro caracterizaron la unión y afinidad a CD155 y la recuperación de la señalización de células T por prototipos sIR diméricos. Además, la administración de prototipos sIRs diméricos en ratones es segura y tienen buenos perfiles farmacocinéticos. A continuación, realizamos un estudio de toxicidad y eficacia como prueba de concepto en un modelo de infección crónica por LMCV. Nuestros resultados proporcionan evidencia de una reducción de la toxicidad inmune inducida por el bloqueo de puntos de control inmunitario (ICB) por el prototipo sIR efector dimérico, lo que lleva a una disminución de la persistencia viral. Además, el prototipo sIR efector dimérico combinado con ICB aumentó la degranulación en células T CD8 estimuladas por TCR. Estos resultados respaldan el desarrollo preclínico adicional del prototipo de sIR efector en modelos de ratones humanizados.Programa de Doctorat en Biomedicin
In silico estimation of thrombogenic risk after left atrial appendage excision: towards digital twins in atrial fibrillation
No full textBackground & aim: The left atrial appendage (LAA) is a highly variable, pouch-like structure in the left atrium prone to thrombus formation, especially in atrial fibrillation (AF) patients. In silico cardiac models can help characterize the LAA's complex morphology and hemodynamics, aiding in identifying pro-thrombotic areas. This study assessed atrial hemodynamics and thrombus formation risk after LAA excision and compared with optimal synthetic excisions and occluder placements in high thrombogenic-risk cases. Methods: We included 33 patients from the MARK-AF study who had persistent AF and underwent excision of the LAA. We quantified the morphological characteristics of the post-excision LAA remnant. With patient-specific atrial geometries and boundary conditions, in silico blood flow simulations were performed. For each patient, we quantified multiple in silico indices to characterize blood flow patterns and identify thrombogenic regions. We performed an in silico comparison of different LAA treatment approaches. Results: In our cohort, 25/33 (76 %) of patients had a post-excision, protruding LAA remnant (LAA depth >10 mm). In silico simulations indicated that patients with a protruding remnant more frequently showed unfavorable values for in silico indices associated with high thrombogenic risk at the excision site. However, a prominent LAA remnant was not the only factor associated with a high thrombogenic risk. An optimal excision or optimal occluder device placement reduced thrombus formation risk. Conclusion: The combination of LAA remnant morphology and hemodynamics contributed to thrombus formation risk. Advanced in silico simulations uniquely enabled the comparison of different therapies, until now only centered on device occluders, contributing to digital twins in AF.This work was supported by the Spanish Ministry of Science, Innovation and Universities GENERALITAAT (PID2022-143239OB-I00) grant, the European Horizon 2020 SimCardioTest (ID 101016496) project, the Horizon 2024 GEMINI (ID 101136438) project, the Distinguished Women Scientist Fund and the Amsterdam University Medical Centers Women in Science Fund
L'impacte de l'educació intramurs en la reeducació i reinserció social de les persones privades de llibertat: estudi de cas del centre penitenciari Quatre Camins
No full textTreball de Fi de Grau en Criminologia i Polítiques Públiques de Prevenció. Curs 2024-2025Tutora: Ares Batlle ManonellesL’educació es presenta com un dret universal per tots els individus, entre ells, també els més exclosos de la societat. En el context penitenciari, es manifesta com una eina essencial per la reeducació i reinserció de les persones privades de llibertat, fent efectiu, per tant, el mandat legislatiu de l’article 25.2. de la Constitució espanyola. D’aquesta manera, el present estudi se centra en analitzar l’impacte de l’educació intramurs en la reeducació i reinserció de les persones privades de llibertat a partir del Centre penitenciari Quatre Camins i el seu Centre de Formació d’adults Salvador Dalí. Per abordar la qüestió, s’han considerat els punts de vista del docent, de l’alumnat i l’observació participant dins d’una lliga de debat en el mateix centre. A partir de la revisió bibliogràfica i coherent amb els objectius preestablerts, es realitzen tres blocs per la realització de l’anàlisi dels resultats: (1) Reeducació: l’efecte en el desenvolupament relacional, el creixement personal i la socialització; (2) Reinserció: la influència en la reincidència, l’ocupabilitat i l’estigma; (3) Limitacions: les institucionals, les de la població penitenciària i del sistema penitenciari.Education is presented as a universal right for all individuals, including the most excluded in society. In the prison context, is an essential tool for the re-education and reintegration of persons deprived of liberty, thus giving effect to the legislative mandate of Article 25.2 of the Spanish Constitution. Therefore, this study focuses on analysing the impact of intramural education on the re-education and reintegration of persons deprived of their liberty based on the Quatre Camins Prison and its Salvador Dalí Adult Learning Centre. In order to address the question, the points of view of the teachers, the students and participant observation were considered within a debate league at the centre itself. Based on the bibliographical review and in line with the pre-established objectives, three blocks are carried out for the analysis of the results: (1) Re-education: the effect on relational development, personal growth and socialisation; (2) Reintegration: the influence on recidivism, employability and stigma; (3) Limitations: institutional and those of the prison population and the prison system