Dipòsit Digital de la Universitat de Barcelona
El Dipòsit Digital de la Universitat de Barcelona és el repositori institucional que conté en format digital els materials derivats de l'activitat docent, investigadora i institucional de la comunitat universitària.
Enviaments recents
Treball de fi de grauUn viatge per les integrals singulars: la transformada de Hilbert(2026-06-10) Filbà i Rico, Marc; Director xxx[eng] The goal of this Bachelor’s thesis is to explore and demonstrate in a thorough and detailed way the theory of the Hilbert transform and singular convolution integrals. To carry it out it will be done a detailed analysis of the previous theory needed to understand both this operator and its boundness in $L^p$ spaces, and finally its generalization to $\mathbb{R}^n$ by means of the Riesz operators and the method of rotations will be studied rigorously. [cat] L’objectiu d’aquest TFG és explorar i demostrar de manera exhaustiva i detallada la teoria de la transformada de Hilbert i les integrals singulars de convolució. Per dur-ho a terme es farà una anàlisi detallada de la teoria prèvia necessària per a entendre tant aquest operador com la seva fitació en espais $L^p$, i finalment s’estudiarà la seva generalització a $\mathbb{R}^n$ de manera rigorosa mitjançant els operadors de Riesz i el mètode de les rotacions.- ArticleMás allá del acuerdo interjueces: protocolo y herramienta para la validación de contenido en investigación educativa(ICE Universitat de Barcelona, 2026-09-01) Calderón, Diego; Carrera, XavierIntroducción: La validez de contenido constituye una fuente de evidencia fundamental en la construcción de instrumentos de medición en ciencias sociales. El juicio de expertos es el procedimiento más extendido para obtenerla; sin embargo, su implementación adolece con frecuencia de falta de transparencia metodológica, criterios de decisión implícitos y ausencia de reglas de interpretación explícitas. Método: Este trabajo presenta un protocolo de validación interjueces orientado a sistematizar y objetivar ese proceso. El protocolo propone la valoración de cuatro indicadores por ítem —univocidad, pertinencia, relevancia y adecuación de la escala de respuesta— mediante una rúbrica de cuatro niveles. Resultados: A partir de las puntuaciones otorgadas por los jueces, se calculan dos índices complementarios: el nivel de calidad del ítem y el grado de consenso interjueces estimado mediante la desviación estándar. La combinación de ambos índices permite adoptar decisiones fundamentadas de conservación, modificación o eliminación de cada ítem conforme a criterios replicables. El protocolo se acompaña de un ejemplo de implementación y de una herramienta en formato Excel que automatiza los cálculos. Discusión: Se discuten los fundamentos metodológicos de la propuesta y sus limitaciones, situándola en el marco de los enfoques contemporáneos de validación basados en evidencia múltiple.
- ArticlePractical argumentation in teaching reflection on practice(MDPI, 2026-08-24) Ledezma, Carlos; Font Moll, Vicenç; Sánchez Brualla, Alicia; Cortés, AlexandrePractical argumentation refers to a form of argumentation oriented towards action. Unlike theoretical argumentation, which primarily concerns the truth or acceptability of propositions, or mathematical argumentation, which is mainly concerned with the production, justification, and validation of mathematical claims, practical argumentation includes an action, decision, or course of conduct as a central component of the argument. Practical argumentation has attracted growing interest in fields such as political science, critical discourse analysis, argumentation theory, and education. In educational contexts, it is especially relevant for analysing how teachers justify pedagogical decisions in relation to learning objectives, classroom circumstances, available means, professional values, and anticipated consequences. Within mathematics education, analytical tools have been developed to structure and represent practical arguments made by prospective and practising teachers during episodes of teaching reflection on practice, for instance through schemes that connect argumentation models with didactical criteria for analysing mathematics teaching and learning. Practical argumentation thus provides a conceptual and analytical tool for making visible the reasons underlying teachers’ decision-making, particularly in situations characterised by tensions between mathematical, didactical, and classroom-management considerations.
- ArticleFate of antibiotic resistance genes under different wastewater treatments and environmental conditions in an Algerian watershed(Elsevier B.V., 2025-06-01) Boulainine, Dalal; Benhamrouche, Aziz; Ballesté Pau, Elisenda; Mezaache-Aichour, Samia; García Aljaro, CristinaIn recent decades, antibiotic resistance has become a major health threat. This study evaluates the efficiency of two wastewater treatment plants (WWTP), conventional activated sludge and advanced filtration-based Enviro-Septic, for removing antibiotic resistance genes (ARGs) and their prevalence in an Algerian watershed. Thirty-five wastewater and 122 river samples were collected. Sampling covered a 50 km transect, from a low-pollution site to a water reservoir, at six sites. The study analyzed different fecal indicators (E. coli (EC), spores of sulfite-reducing clostridia (SRC), somatic coliphages (SOMCPH)), CrAssphage (CrAssPH)), and three ARGs (blaTEM, tetW, and sul1). Mean concentrations in raw sewage from the conventional and Enviro-Septic WWTPs were ∼7.1 and 6.4 log10 (CFU/100 ml) for EC, 6.2 log10 (PFU or CFU)/100 ml for SOMCPH and SRC in both treatments, and ∼7.5 and 5.2 for CrAssPH, respectively. The conventional WWTP achieved reductions of ∼4 log10 for EC and SOMCPH, 3.5 log10 for CrAssPH, and 1 log10 for SRC. The Enviro-Septic system showed similar efficacy for EC and SRC but lower for SOMCPH (2.8 log10) and CrAssPH (2.5 log10). The mean concentrations (log10 GC/100 ml) of ARGs in raw sewage of the conventional and the Enviro-Septic WWTP were 8.6 and 7.3 for tetW, 9.4 and 8.1 for sul1, 8.4 and 6.3 for blaTEM, respectively. Both treatments achieved reductions of 2.9–3 log10 for all ARGs. All river samples tested positive for the three ARGs, with lower concentrations at less fecally polluted sites, showing a reduction of up to 4 log10. Strong correlations (p < 0.05) were observed between culturable indicators, CrAssPH, and ARGs (ρ 0.58–0.96), indicating a strong association between ARGs and human fecal contamination, although other environmental sources cannot be ruled out. This study provides insights into ARG dynamics and supports strategies to mitigate their spread, and protect public health.
- ArticleMegahertz Gravitational Waves from Neutron Star Merger(American Physical Society, 2026-03-10) Casalderrey Solana, Jorge; Mateos, David (Mateos Solé); Sanchez-Garitaonandia, Mikel; Blas, DiegoNeutron star mergers provide a unique laboratory for the study of strong-field gravity coupled to quantum chromodynamics in extreme conditions. The frequencies and amplitudes of the resulting gravitational waves encode invaluable information about the merger. Simulations to date have shown that these frequencies lie in the kilohertz range. They have also shown that, if quantum chromodynamics possesses a first-order phase transition at high baryon density, then this is likely to be accessed during the merger dynamics. Here, we show that this would result in the nucleation of superheated and/or supercompressed bubbles whose subsequent dynamics would produce gravitational waves in the megahertz range. We estimate the amplitude of this signal and compare it to the sensitivity of planned future detectors.