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Revisiones sistemáticas de la literatura con bases de datos académicas
No full textPresentación de las revisiones sistemáticas de la literatura de tipo Scoping Review como base para mapear áreas de conocimiento, detectar huecos de investigación y planificar investigaciones sólidas y de impacto. Presentación del framework SALSA como método para articular una revisión de la literatura. Uso de las bases de datos académicas para constituir la base de la evidencia
Destination selection and flight scheduling for regional airlines at slot-constrained airports
No full textWe present the problem of a regional airline based at a slot-constrained airport, which must select a set of destinations to serve, how many flights per day to operate to each destination, at what time the flights take place and which aircraft operates each flight. Restricting ourselves to the special case of regional airlines, which fly round trips from a central hub, we are able to tackle the four above decisions jointly. By contrast, in the existing literature, these decisions are usually optimised separately for generic airline networks. To solve the proposed problem, we introduce two compact integer formulations: a three-index and a two-index formulation. This latter, however, only solves a relaxation of the original problem because it cannot guarantee that all constraints are respected. Therefore, we embed the two-index formulation into an iterative algorithm which dynamically adds violated constraints. Computational experiments highlight the validity of this approach and provide insights into the characteristics of the solutions.The work of Alberto Santini has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement number 945380
Behavioral and molecular effects of environmental and genetic chronodisruption in mice
No full textEls ritmes circadians regulen funcions fisiològiques essencials, permetent l’adaptació als canvis ambientals. La disrupció d’aquest sistema pot provocar desequilibris homeostàtics amb possibles conseqüències per a la salut. Aquesta tesi explora els efectes de les alteracions ambientals i genètiques en la neurobiologia dels rellotges biològics i les seues conseqüències en el comportament dels ratolins. Els ratolins exposats a cicles llum-foscor irregulars a curt termini van mostrar ritmes diaris moleculars i conductuals alterats, amb canvis significatius en l’expressió gènica a l’hipotàlem i l’escorça prefrontal medial, afectant processos com la neuroplasticitat, la neurotransmissió i les respostes relacionades amb l'estrès. Tot i els efectes cronodisruptius del protocol i les alteracions moleculars detectades, els canvis conductuals van ser mínims. En canvi, els ratolins Bmal1 knockout van presentar una arrítmia profunda i una motivació elevada per recompenses naturals, manifestant també comportaments de tipus compulsiu. L'anàlisi molecular va revelar una desregulació gènica extensa a l’hipotàlem, l’escorça prefrontal medial i l'estriat ventral, afectant processos relacionats amb la motivació, el metabolisme i la neurotransmissió. En conjunt, els nostres resultats suggereixen que ambdues condicions, genètiques i mediambientals, produeixen cronodisrupció en ratolins, desencadenant alteracions en diferents sistemes neurobiològics. Les disrupcions circadianes lleus poden activar mecanismes adaptatius que prevenen d’efectes conductuals, mentre que alteracions genètiques severes condueixen a canvis pronunciats en les respostes associades a la recompensa.Circadian rhythms regulate essential physiological functions, ensuring adaptation to environmental changes. Disruptions to this system can lead to homeostatic imbalances with potential pathological consequences. This thesis explores the effects of environmental and genetic disturbances on the neurobiology of biological clocks and their consequences on behavior in mice. Mice exposed to short-term irregular light-dark cycles exhibited altered behavioral and molecular daily rhythms, with significant changes in gene expression in the hypothalamus and prefrontal cortex, affecting processes such as neuroplasticity, neurotransmission, and stress responses. Despite the assessed chronodisruptive effects of the protocol and produced molecular alterations, behavioral changes were minimal. In contrast, Bmal1 knockout mice displayed profound arrhythmicity and increased motivation for natural rewards, also manifesting compulsive-like behaviors. Molecular analyses further revealed extensive dysregulation of several clock and non-clock genes expressions within the hypothalamus, medial prefrontal cortex and ventral striatum, affecting processes related to motivation, metabolism, and neurotransmission. Overall, our findings suggest that both genetic and environmental conditions that impair biological clock’s function produce physiological chronodisruption in mice, triggering changes in different neurobiological systems. Mild circadian disruptions may elicit adaptive mechanisms that prevent overt behavioral effects, while severe genetic alterations lead to pronounced changes in reward-related responses.Universitat Pompeu Fabra. Doctorat en Biomedicin
Prognostic relevance of preoperative immune, inflammatory, and nutritional biomarkers in patients undergoing gastrectomy for resectable gastric adenocarcinoma: an observational multicentre study
No full textBackground: The aim of this study was to evaluate different preoperative immune, inflammatory, and nutritional scores and their best cut-off values as predictors of poorer overall survival (OS) and disease-free survival (DFS) in patients who underwent curative gastric cancer resection. Methods: This was a retrospective observational multicentre study based on data of the Spanish EURECCA Esophagogastric Cancer Registry. Time-dependent Youden index and log-rank test were used to obtain the best cut-offs of 18 preoperative biomarkers for OS and DFS. An adjusted Cox model with variables selected by bootstrapping was used to identify the best preoperative biomarkers, which were also analysed for every TNM stage. Results: High neutrophil-to-lymphocyte ratio (NLR), high monocyte systemic inflammation index (moSII), and low prognostic nutritional index (PNI) were identified as independent predictors of poor outcome: NLR > 5.91 (HR:1.73; 95%CI [1.23-2.43]), moSII >2027.12 (HR:2.26; 95%CI [1.36-3.78]), and PNI >40.31 (HR:0.75; 95%CI [0.58-0.96]) for 5-year OS and NLR > 6.81 (HR:1.75; 95%CI [1.24-2.45]), moSII > 2027.12 (HR:2.46; 95%CI [1.49-4.04]), and PNI > 40.31 (HR:0.77; 95%CI [0.60,0.97]) for 5-year DFS. These outcomes were maintained in the whole cohort for NLR and moSII (p < 0.05) but not in stage II and for PNI in all tumoral stages. The associations of NLR-PNI and moSII-PNI were also a relevant prognostic factor for OS. Conclusions: High NLR, high moSII (for stages I and III), and low PNI (regardless of tumour stage) were the most promising preoperative biomarkers to predict poor OS and DFS in gastric cancer patients treated with curative intent
Attributing heat-related mortality to climate change
No full textClimate change significantly exacerbates public health risks, particularly heat-related mortality. This PhD thesis examines the impact of human-induced climate change on heat-related deaths in Europe, focusing on regional and demographic disparities. Using Eurostat’s weekly mortality data, stratified by sex and age, the research ensures transparency and comparability.
Study I assesses heat-related mortality in 35 European countries, finding that 56% of over 38,000 deaths during the record-breaking summer of 2022 were attributable to climate change. Study II uses extreme value theory to analyze the probability of such events, revealing a tripling likelihood due to climate change.
This thesis underscores the pressing need for integrated adaptation and mitigation strategies, emphasizing tailored, region-specific approaches to protect vulnerable populations. It highlights the role of health impact climate attribution in driving climate litigation and shaping policies, contributing valuable insights to the intersection of climate change and public health.El cambio climático agrava significativamente los riesgos para la salud pública, especialmente la mortalidad relacionada con el calor. Esta tesis examina el impacto del cambio climático antropogénico en las muertes relacionadas con el calor en Europa, con un enfoque en las disparidades regionales y demográficas. Utilizando datos semanales de mortalidad de Eurostat, estratificados por sexo y edad, la investigación garantiza transparencia y comparabilidad.
El Estudio I analiza la mortalidad por calor en 35 países europeos, encontrando que el 56% de más de 38,000 muertes durante el verano récord de 2022 se atribuyen al cambio climático. El Estudio II utiliza teoría de valores extremos para analizar la probabilidad de tales eventos, revelando una triplicación de su frecuencia debido al cambio climático.
Esta tesis resalta la necesidad urgente de estrategias integradas de adaptación y mitigación, enfatizando enfoques específicos para proteger a las poblaciones vulnerables.Programa de Doctorat en Biomedicin
Essays on Market Power
No full textThis thesis consists of three chapters that explore how firm’s behaviour impacts
worker outcomes, focusing specifically on the implications of market power on
entrepreneurship, wages and inequality. The first chapter shows how forces that
shape market power can also lead to lower entrepreneurship rates accompanied
by increasing income inequality. The second chapter develops a novel theory that
shows how product and labor market power affect US wage inequality. We find
that declining competition lowers wages by 10%, contributes 8.1% to the rise in
the skill premium, and explains half of the increase in between-establishment inequality.
The third chapter shows how declining competition can rationalize stagnating
wages even in the presence of increasing productivity. We find that rising
monopoly power and stable monopsony contribute to this gap, with monopoly
accounting for 75% of wage stagnation and monopsony for 25%.Esta tesis consta de tres capítulos que exploran cómo el comportamiento de las
empresas impacta en los resultados de los trabajadores, centrándose específicamente
en las consecuencias del poder de mercado en el emprendimiento, los salarios
y la desigualdad. El primer capítulo muestra cómo las fuerzas que configuran
el poder de mercado también pueden conducir a menores tasas de emprendimiento,
acompañadas de una creciente desigualdad de ingresos. El segundo
capítulo desarrolla una nueva teoría que muestra cómo el poder en el mercado
de productos y del trabajo afecta la desigualdad salarial en Estados Unidos. Encontramos
que la caída de la competencia reduce los salarios un 10%, contribuye
a un 8,1% del aumento de la prima por calificación y explica la mitad del aumento
de la desigualdad entre establecimientos. El tercer capítulo muestra cómo la
disminución de la competencia puede racionalizar el estancamiento salarial incluso
en presencia de una productividad creciente. Encontramos que el creciente
poder de los monopolios y el monopsonio estable contribuyen a esta brecha: el
monopolio representa el 75% del estancamiento salarial y el monopsonio el 25%
del mismo.Programa de Doctorat en Economia, Finances i Empres
La televisió pública a Europa (segona part): la crònica dels esdeveniments i els reptes de futur
No full textUnderstanding the hemodynamic changes in fetuses with coarctation of the aorta using a lumped model of fetal circulation
No full textCoarctation of the aorta (CoA) is a common congenital heart defect characterized by aortic narrowing. Prenatally, it has mild hemodynamic effects as right ventricular disproportion and ductus arteriosus (DA) dilation occur as adaptive mechanisms, but their impact on CoA hemodynamics remains poorly understood. To investigate this, we built a closed 0D computational model of fetal circulation and simulated different CoA cardiovascular remodeling patterns, including aortic isthmus (AoI) narrowing, ventricular disproportion, and DA dilation. Our results showed mild AoI narrowing (80% of reference diameter) required up to 1.7 right/left ventricular end-diastolic volume ratio and 115% DA dilation to maintain physiological pressures, wall shear stresses, and organ perfusion. In contrast, severe narrowing (20% of reference AoI diameter) required up to 5 right/left ventricular end-diastolic volume ratio and 125% DA dilation, highlighting the necessity of co-occurrence of prenatal ventricular disproportion and DA dilation to compensate for AoI narrowing. These physiological regions were validated with ultrasonographic measurements from 7 controls and 9 CoA patients. We compared blood pressures, velocities, and volumetric flow rates across different fetoplacental anatomical sites. AoI velocity showed a delayed retrograde flow peak and increased antegrade diastolic velocity with greater AoI narrowing, which may aid in diagnosing CoA. Minimal differences were observed in other velocities and pressures. Volumetric flow rates across varying degrees of AoI narrowing decreased in the AoI and mitral and aortic valves, remained stable in the middle cerebral and umbilical arteries, and increased in the DA and tricuspid and pulmonary valves. Therefore, we corroborated that in fetal CoA a redistribution of blood flow occurs to ensure perfusion of the brain and placenta, without a significant alteration in fetal hemodynamics (blood pressure and velocities) except for increased diastolic velocities in the AoI.This work was supported by European Social Fund Plus (ESF+) and Generalitat de Catalunya (Joan Oró Grant 00237 to I.V.B.; Beatriu de Pinos Grant 2018-BP-00201 to P.G.C.), by the H2020 Marie Skłodowska-Curie Actions (Marie Skłodowska-Curie Grant 801370 to P.G.C), by ESF+ and Ministerio de Ciencia e Innovación (RYC2023-043724-I to P.G.C. and RYC2022-035960-I to G.B.), and by Fundació la Marató de TV3 (Project CoALeS 650/C/2020). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Walras-Bowley lecture: market power and wage inequality
No full textWe propose a theory of how market power affects wage inequality. We ask how goods and labor market power jointly determine the level of wages, the skill premium, and wage inequality. We then use detailed microdata from the U.S. Census Bureau between 1997 and 2016 to estimate the parameters of labor supply, technology, and the market structure. We find that a less competitive market structure lowers the average wage of high-skilled workers by 11.3%, and of low-skilled workers by 12.2%, contributes 8.1% to the rise in the skill premium, and accounts for 54.8% of the increase in between-establishment wage variance.Eeckhout gratefully acknowledges support from the ERC, Advanced Grant 882499 and Deb from "la Caixa" Foundation (ID 100010434) fellowship (code LCF/BQ/DR19/11740003)
Multivariate mean estimation with direction-dependent accuracy
No full textWe consider the problem of estimating the mean of a random vector based on N independent, identically distributed observations.We prove the existence of an estimator that has a nearoptimal error in all directions in which the variance of the one-dimensional marginal of the random vector is not too small: with probability 1−δ, the procedure returns μN which satisfies, for every direction u∈Sd−1, ⟨μN−μ,u⟩≤NC(σ(u)log(1/δ)+(E∥X−EX∥2)1/2), where σ2(u)=Var(⟨X,u⟩) and C is a constant. To achieve this, we require only slightly more than the existence of the covariance matrix, in the form of a certain moment-equivalence assumption.Gábor Lugosi was supported by the Spanish Ministry of Economy and Competitivity, Grant PGC2018-101643-B-I00 and FEDER, EU, and by 'Google Focused Award Algorithms and Learning for AI'