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Exploring Gender Differences in Persistence: Analyzing Test-Taking Behaviours in High-Stakes Assessments
No full textThis study leverages data from a large-scale university online exam platform during the 2019/2020 academic year to analyze gender differences in test persistence and performance, conditional on study area (STEM vs. non-STEM). It further examines the moderating effect of exam stakes on these gender patterns. Persistence is conceptualized as sustained effort throughout the test, measured via performance decline over the course of the exam—providing a behavioural and reliable measure of test persistence that overcomes limitations of subjective effort assessments. Consistent with prior research on gender effects in STEM performance, the results reveal that within social science programs, female students tend to underperform compared to their male counterparts in STEM subjects, while no gender gaps emerge in non-STEM courses. This pattern is observed primarily in low-stakes exams; however, in high-stakes exams, gender gaps are effectively bridged. These findings shed light on the contextual factors—such as self-concept and identity—that influence performance, as well as the role of external incentives in moderating gender patterns shaped by these factors. Overall, the study highlights the importance of accounting for contextual incentives when assessing gender differences in effort and performance.We would like to the funding institution, Agencia Estatal de Investigación (AEI). This paper is part of the project I+D+iPID2020-117525RB-I00, financed by MICIU/AEI/10.13039/50110001103
La libertad sexual en el ámbito de la pareja
No full textTrabajo realizado al amparo del Proyecto I+D+i de Generación de conocimiento PID2021-123493OB100: "El acceso a la justicia de las personas vulnerables". IP1: Mercedes Llorente Sánchez-Arjona, IP2: Vicente C. Guzmán Fluja
Experimental compressive damage analysis on holed laminates under dynamic loadings using in-situ MHz synchrotron X-ray phase contrast imaging
No full textThis study highlights the importance of investigating the behaviour of the inner layers of carbon fibre-reinforced polymer (CFRP) laminates under dynamic compression, using Synchrotron-based techniques to understand damage initiation and failure propagation at high strain rates. Open and filled hole specimens with three different CFRP architectures were tested using the Split Hopkinson Pressure Bar (SHPB). Digital image correlation (DIC) and Synchrotron-based X-ray MHz radiography were performed simultaneously with ultra high-speed cameras (two Shimadzu HPV-X2 for X-ray images and one Photron SAZ for visible light). This allowed the first observation of matching outer and inner failures with surface strain fields at a micrometer level. Results showed that, in certain conditions, failure initiated earlier in the inner layers, leading to through-thickness propagation. This correlation between strength and internal damage initiation might be overlooked if only outer visible light images are used. The proposed methodology, which emphasised post-processing of X-ray images, can serve as a baseline for future research on the behaviour of inner layers of composite materials under high strain rates. Additionally, analysis of different CFRP architectures revealed their influence on unloading time after initial failure.The ESRF, Grenoble, France is acknowledged for providing beamtime and assistance under Beamtime Proposal MA-5288 and under the beamtime proposal MI-1397 (Shock BAG). B.L. acknowledges funding from the EPSRC (EP/W003333/1). The research leading to the developments described was funded within the framework of the projects: the Vicerrectorado de Política Científica project from the University Carlos III of Madrid, Spain 2013/00413/004, 2020/00123/001, 2023/00264/001, 2023/00409/001 and 2022/00094/001
Modernización, transformación e Historia Antigua. El viaje a Italia organizado por Elías Tormo en 1927
No full textAre money demand equations still alive and kicking? Historical evidence of cointegration for the UK, using nonlinear techniques
No full textSince the influential works of Friedman and Schwartz (1963, 1982) and Hendry and Ericsson (1991), on the monetary history of the United States of America and the United Kingdom from 1876 to 1975, there has been a great concern in the literature about the instability of money demand functions. This concern together with the results of the New Keynesian´s models (Woodford, 2003), produced the abandon of money as an instrument of monetary policy. Recently, using M1 as the measure of money, Benati, Lucas, Nicolini and Weber (2021) have shown, for a shorter and recent period of time, that there is a stable long-run money demand for a long list of countries. However, to date there are no studies showing that stable long-run and short-run money demand equations exist since the XIX century and how it can be used to inform monetary policy based on the quantitative theory of money. By means of nonlinear cointegration and nonlinear error-correction models, this paper presents evidence of UK stable long-run and short-run money demands of real broad monetary balances from 1874 to 2023. These equations provide with key elements to identify periods of excess money demand generating periods of 6.5% excess inflation, over the historical 2.2% average. Stable Money demand estimates provide useful policy rules and additional cross-check instruments for monetary policy to reach inflation targets. Furthermore, they help identifying spurious transmission channels of monetary policy, when theoretical models impose invalid common
factor restrictions.A. Escribano acknowledges the funding received from the UC3M Chair for Internationalization, the Ministry of Economics of Spain (ECO2016-00105-001, MDM 2014-0431), the Community of Madrid (MadEco-CM S2015/HUM-3444 and the Agencia Estatal de Investigación (2019/00419/001) and Ministerio de Ciencia e Innovación (PID2022-141414OB-100)
Generalized volumetric energy balance for directly irradiated bubbling fluidized beds
No full textBeam-down concentrating solar towers are receiving much attention from the scientific and industry sectors to generate electricity, produce chemical fuels, and drive energy-intensive processing of materials. The easy thermal design of the solar receiver is essential for the deployment of this renewable energy. This work proposes the equations and methodology to solve the steady-state energy balance of directly irradiated bubbling fluidized beds. The analysis focuses on solving the heating of the bed surface assuming that the energy flux received at the bed surface is absorbed through a layer of particles. The proposed methodology considers a volumetric energy balance of the top-bed surface to calculate the bed temperature. The bed surface emissivity ( ) is a critical parameter in order to solve such an energy balance. To deal with the radiative losses, a correlation is proposed to estimate bed emissivity at the top-bed surface that depends on the dimensionless length number, . The results are validated against both new experimental and literature data for the open and closed fluidized bed receivers. The absolute relative error when estimating the steady state temperature of the systems studied is about 5.2 % (on average). The relative error follows a Gaussian distribution guaranteeing an unbiased estimation of the bed temperatures at steady-state operation.The authors gratefully acknowledge the financial support provided by the grant (PID2021–122278OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. This work was partially funded by the project PID2021–127322OB-I00 (funded by Ministerio de Ciencia e Innovación MICIN/AEI/10.13039/501100011033 and by NextGenerationEU/PRTR); Project TED2021–131046B (funded by Ministerio de Ciencia e Innovación MCIN/AEI /10.13039/501100011033 and by NextGenerationEU/PRTR). Project TED2021–131046BI00 funded by the Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) Plan de Recuperación, Transformación y Resiliencia-NextGenerationEU. Project SBPLY/21/180501/000017 (funded by the Regional Government of Castilla-La Mancha); and Project 2022-GRIN-34343 (funded by Universidad de Castilla-La Mancha)
Dataset of keywords used by European political parties on Facebook
No full textThis dataset contains the frequency of thousands of terms (or keywords) used by political parties in the posts they have published in their Facebook pages. The data set is composed by 20,317 keywords from posts published by 279 European political parties from 28 countries and spans 5 years, from January 2019 to December 2023. Due to the large diversity of languages in the analysed countries, we have translated every post into English to compile this dataset. We also provide an open-access web portal: EU Political Barometer, in which a wide variety of analyses can be carried out without the need of working directly with the dataset. This allows scientists without a data analysis background to access the information embedded within the dataset. The information included in the dataset may be of value for social scientists that wants to understand the evolution of the topics employed by political parties in Europe based on a widely used political communication tool such as Facebook.This research has received funding from: the project ENTRUDIT (Grant TED2021-130118B-I00) funded by the MCIN/AEI/10.13039/501100011033 and the NextGeneration EU/PRTR funds; the Ministerio de Asuntos Económicos y Transformacion Digital and the European Union-NextGenerationEU through the project PRITICACLOUD and the AImpulsa chair (Grant TSI-100922-2023-1)
Diseño de una unión mecánica entre carcasa y banda de rodadura para eco-neumáticos
No full textAunque es bien conocido el problema medioambiental y para la salud que generan la fabricación, el uso y los residuos procedentes de los neumáticos, es un asunto de gran envergadura y difícil de resolver. En este contexto, y habida cuenta de la enorme importancia del neumático para la dinámica, comportamiento y seguridad de los vehículos automóviles, surge la necesidad de crear una nueva estructura de neumático que permita separar la parte sometida a desgaste y la parte estructural, manteniendo sus capacidades. Este reto podría ser enfrentado por la industria del recauchutado, que sustituye la banda de rodadura cuando está desgastada, aprovechando la carcasa si esta se encuentra en buen estado. Sin embargo, esto mitiga sólo parcialmente el problema, reduciendo la cantidad de residuos generados, pero no evita los microplásticos altamente nocivos que se generan por el desgaste de la banda de rodadura.
Con el fin de introducir materiales de menor impacto medioambiental en la banda de rodadura, resulta necesario ir más allá de las soluciones actuales, posibilitando el uso de materiales completamente diferenciados en la carcasa y en la banda de rodadura, y evitando la necesidad de unirlos mediante procesos termoquímicos. Es en este punto en el que surge el proyecto ECOTIRE/iECOTIRE, con un planteamiento novedoso, basado en la unión mecánica entre ambas partes del neumático.
En este estudio se avanza en el diseño de la unión mecánica entre carcasa y banda de rodadura mediante el estudio de geometrías de unión y materiales candidatos a ampliar la vida útil de la carcasa o a sustituir al caucho en la banda de rodadura. Para ello se ha diseñado y fabricado un dispositivo para ensayar “huellas de contacto virtuales”, obteniendo resultados con diferentes configuraciones de unión mecánica. Además, este estudio experimental sirve de base para la definición de un modelo de simulación que permitirá ampliar las configuraciones estudiadas, así como las pruebas a las que serán sometidas.
Por último, con los resultados alcanzados en este documento, se definirán geometrías y materiales-candidatos que puedan ser aplicados en un primer prototipo completo de neumático sostenible, ECOTIRE.Esta publicación forma parte del proyecto de I+D+i: TED2021-129604B-100, financiado por MCIU/AEI/10.13039 501100011033 y por la Unión Europea NextGeneration EU PRTR. Adicionalmente
Efficiency in poverty reduction in Bolivia
No full textA decline in poverty at the national level can mask regional disparities related to heterogeneous levels of efficiency among states that may limit the effectiveness of poverty reduction programs. To address this, we propose an empirical framework to unveil regional differences in poverty reduction and their drivers. Our method identifies the potential for poverty reduction and the factors crucial for designing place-based public policies. Applying this method to Bolivia for the period 2000-2021, we find that inefficiency in poverty reduction is largely persistent in specific states, underscoring the need for long-term strategies, especially those targeting informality and unemployment
Online personal influence: the dynamics, mechanisms and antecedents of political persuasion in social media
No full textMención Internacional en el título de doctorThe rise of the internet and social media significantly expanded media choice, prompting rapid changes in citizens’ information habits and transforming the possibilities for political persuasion. In recent decades, a burgeoning area of research has investigated how content on these platforms may influence public opinion and lead to significant democratic consequences such as political polarization. However, these studies have generally been inconclusive. While some suggest that users tend to consume like-minded content that reinforces their opinions, others argue that social media facilitates exposure to diverse political viewpoints and even attitude change. In this thesis, I extend this growing body of research employing a mixed methods design that combines qualitative and quantitative data. The qualitative approach, based on 73 in-depth interviews with Spanish social media users, explores users’ perceptions of political persuasion in social media, a perspective previously underexplored. It provides new theoretical insights into the persuasive relationships that users engage in, the attributes of political persuasion in social media and how different users persuade. The quantitative approach, drawing on a two-wave panel survey conducted in Spain (N = 570), examines the direct and indirect pathways by which incidental news exposure, a widespread and accidental news practice on social media, may predict political attitude change. Findings reveal that incidental news can lead to political persuasion both directly and indirectly. Overall, this thesis enhances the literature by unveiling the real-world, contingent factors and mechanisms that drive political persuasion on social media.Programa de Doctorado en Investigación en Medios de Comunicación por la Universidad Carlos III de MadridPresidente: Alberto Ardèvol Abreu.- Secretaria: Laia Castro Herrero.- Vocal: Marko Skori