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Airline Economics
No full textThis Special Issue brings together a collection of empirical and theoretical contributions that deepen our understanding of airline economics through a diverse range of topics, methodologies, and geographic focuses. The contributions cover key aspects of airline behavior, from pricing strategies and cooperative agreements to environmental policy responses and demand-side transformations. In parallel, several papers engage with broader questions of transportation system integration, intermodal competition, and the role of regulation in shaping outcomes for firms, consumers, and society. Collectively, these papers highlight how the airline industry is adapting to structural changes, e.g., the long-term effects of the COVID-19 pandemic (such as the rise of telecommuting and remote work), evolving competitive environments, environmental constraints, and regulatory pressures. The findings presented here offer both rigorous academic insights and valuable policy guidance. By leveraging data-rich analyses and theoretical modeling, these papers collectively inform pressing questions regarding sustainability, equity, and efficiency in the air transport sector
Dynamic multi-cue weighting in the perception of Spanish intonation: Differences between tonal and non-tonal language listeners
No full text[eng] This study investigates cue-weighting differences in intonation perception between tonal and non-tonal languages, specifically focusing on how native Spanish listeners and Mandarin learners of Spanish identify intonation categories using changes in multiple acoustic dimensions. Employing a relatively continuous response scale, we analyzed listener performance in two perceptual tests, in which stimuli were generated by manipulating the suprasegmental cues in sentence-final positions. The results of data analyses indicate that while f0 and duration cues are significant for intonation categorization in both Spanish and Mandarin listeners, intensity appears to be a redundant cue that exerts limited effect only on native Spanish listeners. Contrary to the general claim of a tonal language benefit in pitch perception, our two language groups showed similar sensitivities to f0 linear transitions perceived as sentence intonation. Moreover, Spanish natives used higher f0 contours for question recognition compared to Mandarin learners and relied more heavily on secondary cues in their auditory judgments. The study also demonstrates that perceptual weighting varies across acoustic conditions and stress patterns, suggesting that the dynamic mapping between acoustics and intonation is shaped by language background as well as specific acoustic and word-level suprasegmental contexts
H2O2 electrosynthesis in a reactor without forced aeration for the complete degradation of antibiotics by photoelectro-Fenton-like process at neutral pH
No full textInnovative systems for H2O2-based advanced wastewater treatment avoiding the need of external aeration are pursued with great interest, since they allow decreasing the capital expenses significantly. This work shows the good performance of a rotating cylinder electrode (RCE) reactor for continuous H2O2 electrosynthesis sustained by anodic oxygen, and its use in the degradation of the antibiotic enrofloxacin (ENR) by photoelectro-Fenton (PEF) process at pH 7 using Fe(III)-ethylenediamine-N,N´-disuccinic (EDDS) acid complex as catalyst. For H2O2 accumulation in different aqueous matrices, each peripheral velocity (U) was linked to a specific limiting current (IL) using a mass transport correlation. H2O2 concentrations in the range of 2.4–3.7 mM were attained after 60 min of electrolysis at U = 198.9 cm s−1 (1000 rpm, IL = 0.31 A). At that rotation rate, the elimination of 5 mg L−1 ENR was 100 % after 30 min in a 50 mM Na2SO4 + 0.1 mM Fe(III)-EDDS. Moreover, ENR removal over 95 % was reached at 60 min in actual urban wastewater. The main by-products were oxalic and oxamic acid, accompanied by nitrate, ammonium, and fluoride ions. The superiority of PEF process as decontamination process was verified from the lower toxicity of the treated ENR solutions
Biomonitorización de los metabolitos de los aditivos plásticos en muestras de orina de recién nacidos
No full textTreballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2025, Tutores: Mercè Granados, Ethel EljarratThis project focuses on the analysis of plasticizers and parabens in the urine of newborns placed in incubators, with the aim to identify and evaluate the presence of potentially hazardous chemicals in these extremely vulnerable children. Given that these newborns have a developing biological system, exposure to these substances could have detrimental health effects both in the short and long term. Using advanced analytical techniques, such as high-performance liquid chromatography and quadrupole time-of-flight mass spectrometry (QTOF), chemicals including phthalates (PAEs), organophosphate esters (OPEs), and parabens were investigated through the QuEChERS extraction technique. The objective is to assess the presence of these compounds, which are linked to endocrine disruptors commonly found in incubator environments and medical or healthcare materials.
Although no statistically significant relationship was found between the number of days in the incubator and compound concentrations, visual results suggest that most premature newborns could experience a greater accumulation of additives. The results showed differences in the concentrations of these substances across different urine samples, which might suggest that exposure varies depending on the environment and the materials used during the stay, as well as possible interventions. OPEs were the compounds with the highest concentration, followed by phthalates, while parabens, although present in lower concentrations, were
detected in more urine samples.
Even though no immediate health risk for newborns was observed based on the detected levels, the study emphasizes the importance of continuous monitoring and the consideration of strategies to reduce exposure to these compounds, particularly in neonatal intensive care and hospital settings. Additional factors, such as the type of material or characteristics of the newborns, may influence exposure levels, highlighting the need for further in-depth studies to optimize safety in hospital environments and contribute to the development of stricter regulations regarding the use of chemical additive
«Fiscalidad, parafiscalidad y regulación económica en el sector eléctrico español», de Marta Villar Ezcurra, con prólogo de Luis M. Cazorla Prieto Editorial Aranzadi, 2023, 216 páginas
No full textRessenya del llibre «Fiscalidad, parafiscalidad y regulacióneconómica en el sector eléctricoespañol», de Marta Villar Ezcurr
Redesigning choice to tackle school segregation: the impact of Barcelona’s desegregation policies
No full textThe relationship between school choice and segregation remains a contentious issue in both academic and policy spheres. In recent years, the redesign of school choice policieshas gained traction as a strategy to mitigate their negative impacts on school segregation. In this context, Barcelona (Spain) implemented desegregation policies in 2019, primarily based on redesigning specific school choice policy instruments to reduce the uneven distribution of socially disadvantaged students among schools. This study examines the impact of these policies on school segregation and explores how their effectiveness varies according to the characteristics of different areas within the city. The findings indicate that desegregation policies have reduced the uneven distribution of socially disadvantaged students and their isolation in specific schools. However, our results also show that, in each area, impacts are mediated by factors such as residential segregation, the enrolment in subsidised private schools, the share of students schooling outside their educational area, and the prevalence of siblings already attending a school, which confers priority access in admissions. We argue that the relative success of Barcelona’s school choice reform in addressing school segregation lies in its shift from a coordinated to a controlled choice model
Decentralizing happiness
No full textThis article investigates the impact of decentralization of political and economic power on happiness levels globally. We make two contributions to the literature. First, we expand the empirical analysis beyond the typical focus on Western countries by using data from the World Happiness Report (2019–2022), covering 131 countries worldwide. Second, we examine the specific mechanisms driving the relationship between decentralization and happiness. By distinguishing between decentralized and centralized government expenditures, revenues, and taxes, we show that higher subcentral spending—particularly when funded by transfers—positively influences happiness. Our findings reveal that countries with decentralized governance structures report higher happiness levels, primarily driven by increased subcentral spending. Furthermore, happiness is more positively affected when local services are funded through transfers from higher levels of government, rather than local taxes
The Effect of Access to Legal Abortion on Fertility, Marriage and Long-term Outcomes for Women
No full textWe evaluate the short- and long-term effects for women of access to legal, subsidised abortion. We find evidence that the legalisation of abortion in Spain in 1985 led to an immediate decrease in births, more pronounced for younger women in provinces with a higher supply of abortion services. Affected women were more likely to graduate from high school, less likely to marry young, less likely to divorce in the long term and reported higher life satisfaction as adults. We find at most small reductions in completed fertility, while we do not find meaningful effects on labour market outcomes in the long run
Is it truly pedagogical innovation? Students' experiences with digital platforms in primary education
No full textThe expansion of digital platforms in schools poses significant challenges for understanding pedagogical dynamics in digitalised contexts. This study examines how digitally mediated pedagogical practices are shaped and experienced in primary education from the students’ perspective. A qualitative methodology was employed, combining six focus groups conducted in six different schools across Catalonia with ethnographic observations over three months in one primary school in the same region. The findings identify three types of platform-related practices in schools: (1) reproductive, (2) enriching, and (3) transformative uses. While some transformative practices are described, instrumental logics generally persist, limiting students’ active participation. The study highlights the need to rethink pedagogical design in digital con texts by placing children’s voices at the centre of the analysis
Boundedness for proper conflict-free and odd colorings.
No full textThe proper conflict-free chromatic number, , of a graph is the least positive integer such that has a proper -coloring in which for each non-isolated vertex there is a color appearing exactly once among its neighbors. The proper odd chromatic number, , of is the least positive integer such that has a proper coloring in which for every nonisolated vertex there is a color appearing an odd number of times among its neighbors. We clearly have . We say that a graph class is -bounded ( bounded) if there is a function such that for every . Caro, Petruševski, and Škrekovski (2023) asked for classes that are linearly bounded ( -bounded) and, as a starting point, they showed that every claw-free graph satisfies , which implies .
In this paper, we improve the bound for claw-free graphs to a nearly tight bound by showing that such a graph satisfies , and even if it is a quasi-line graph. These results also give further evidence to a conjecture by Caro, Petruševski, and Škrekovski. Moreover, we show that convex-round graphs and permutation graphs are linearly -bounded. For these last two results, we prove a lemma that reduces the problem of deciding if a hereditary class is linearly -bounded to deciding if the bipartite graphs in the class are -bounded by an absolute constant. This lemma complements a theorem of Liu (2024) and motivates us to further study boundedness in bipartite graphs. Among other results, we show that biconvex bipartite graphs are bounded, while convex bipartite graphs are not even -bounded, and we exhibit a class of bipartite circle graphs that is linearly -bounded but not -bounded