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La exégesis del ciclo de Abraham ejerce
una poderosa influencia en la lectura soteriológica
que hace Hilario de Poitiers de la fe como factor
transformador del ser humano. Dentro de la lectura
tipológica a la que somete a los diversos personajes
que protagonizan el ciclo en Génesis, destaca
el de Agar, testigo de dos teofanías, que podría ser
valorada como trasunto de los gentiles que se salvan
por su fe. Esta caracterización hilariana coloca
a Agar en un plano prefigurativo relevante que matiza
la tradicional imagen mediatizada por la interpretación
alegórica paulina en la que se ensalza a
Sara.

In the last decades, various policies have been implemented to reduce air pollution exposure and improve public health outcomes. Among these, low emission zones (LEZs) have been shown to effectively enhance air quality and health outcomes. However, their potential positive externalities on other outcomes, such as academic performance, remain largely unexplored. This study examines the LEZ introduced in the city of Madrid in late 2018 and investigates its impact on the academic performance of students schooled in the designated area. Using a difference-in-differences design, we demonstrate the policy’s effectiveness in improving air quality during its first 4 years. Subsequently, we find a significant increase of 0.20 standard deviations in the average EvAU scores (a high-stakes examination for university admission) among high schools located within the LEZ, a critical advantage for students seeking entry into the most competitive university programmes. Notably, our findings reveal positive spillover effects in the surroundings of the LEZ area and a greater improvement with longer and earlier exposure to cleaner air. Overall, this study offers compelling evidence of the educational benefits resulting from the implementation of a low emission zone that successfully improves air quality.

Aunque el reparto de carga entre planetas de transmisiones de engranajes planetarios en fase secuencial se ha estudiado en el pasado, las técnicas de resolución requeridas basadas en el Método de Elementos Finitos resultan en un alto consumo de tiempo y un alto costo computacional. Esto limita las posibilidades de emprender estudios extensos que tengan en cuenta un alto número de casos que permitan buscar soluciones óptimas o extraer conclusiones generales. Además, la determinación de las curvas de error de transmisión, rigidez de malla variable en el tiempo y reparto de carga entre pares de dientes en contacto simultáneo también son complicadas. En este trabajo se ha desarrollado un modelo analítico para la simulación de la rigidez de malla variable en el tiempo, el error de transmisión cuasiestático y la relación de reparto de carga entre planetas y pares de dientes de transmisiones planetarias de engranajes rectos. Se basa en modelos similares para engranajes rectos externos e internos desarrollados previamente y se ha validado mediante comparación con un modelo híbrido basado en el Método de Elementos Finitos y correlación teórico-experimental.

This article analyses the impact of the crises on the level of inequality between native and migrant origin children in twenty-first-century Spain. We use microdata from the Spanish Labour Force Survey (2000–2022) to study the risk for migrant and native children of living in a household with no working adults. We hypothesize that the assimilation of the immigrant population—after more than two decades in the country—might have contributed to reducing the impact of the COVID-19 crisis. Results show that the 2008 crisis substantially increased the gap between migrant and native children, while the impact of the pandemic has been milder. Moreover, social origin has a stronger protective effect for native children compared with children with a migrant background, especially during periods of economic downturn. However, we find that among children of low social origin, migrant children are less likely to live in a household with no working adults.

Introducción: El tabaquismo es un problema de salud pública. Existe una asociación entre el tabaquismo y el desarrollo de depresión perinatal.
Objetivo: Estimar la prevalencia de la depresión prenatal y analizar los factores de riesgo que predicen el desarrollo de depresión prenatal en un grupo representativo de mujeres españolas gestantes fumadoras.
Método: Se llevó a cabo un estudio transversal en una muestra de 1.524 de embarazadas en el primer trimestre de gestación. Se les administró el Cuestionario de salud del paciente (PHQ-9) y el Inventario revisado de predictores de depresión posparto (PDPI-R).
Resultados: Se encontró una tasa de depresión antenatal en mujeres fumadoras del 25,6%. Se encontraron como predictores de depresión prenatal en fumadoras el estresor de enfermedad grave de un familiar y la falta de apoyo emocional de la pareja.
Conclusiones: La falta de apoyo social y la carencia de estrategias adaptativas de afrontamiento del estrés es posible que hagan más proclive que la mujer continúe fumando en el embarazo y aumentan el riesgo de depresión perinatal.

In this paper, we investigate the implementation of the finite difference method on arbitrary meshes in conjunction with a fixed-point algorithm for the lubrication problem of a journal bearing with cavitation, considering the Elrod-Adams model. We establish numerical properties of the generalized finite difference scheme and provide several illustrative examples.

Tras la consecución del estatuto de ciudadanía de la Unión Europea con ocasión del Tratado de Maastricht, se propició la configuración, en el ordenamiento jurídico de la UE, de un derecho a la libre circulación de carácter autónomo, sin vinculación con la actividad y los fundamentos económicos que lo caracterizaban en el inicio del proceso de integración comunitario, y que ha supuesto la consolidación de dos libertades o derechos fundamentales como son la libre circulación y la libertad de residencia en el territorio de los Estados miembros de la Unión Europea. Estas libertades, consagradas en los Tratados y en la Carta de Derechos Fundamentales de la Unión Europea, han tenido también un importante desarrollo legislativo y atención jurisprudencial; todo ello a la vez que se ha producido una consolidación del Espacio Schengen con el objetivo de suprimir el control de fronteras.
En este trabajo realizo una aproximación a los fundamentos y configuración de estas libertades, y su consolidación, atendiendo en particular al ámbito de aplicación personal y el contenido de las libertades fundamentales, además de analizar la jurisprudencia del Tribunal de Justicia más reciente y relevante en este campo para dar respuesta a algunos de los interrogantes que aún se plantean para el ejercicio de estos derechos.

Environmental enrichment (EE) provides an improvement in the housing conditions of experimental animals, such as laboratory rats, with greater physical and social stimulation through toys and company in the home cages. Its use is known to influence performance of experimental protocols, but these effects have not been well determined in the schedule-induced drinking (SID) procedure. The main goal of this study was to investigate the effects of EE on the acquisition of SID in 24 12-week-old male Wistar rats, divided into two groups, a group with EE housed with toys and companions, and a group without enrichment in individual housing conditions without toys (social isolation and no environmental enrichment, INEE). A total of 25 sessions, under a fixed time 30 s food reinforcement schedule and with access to water in the experimental chambers were carried out. Sessions lasted 30 min. The results showed that the EE group developed faster the excessive drinking pattern of SID, and drank to higher levels, than the INEE group. The greater development of SID in the EE group contradicts the view of schedule-induced behavior as linked to stress reduction and better suits with the conception of induction related to positive reinforcement.

Some contagious diseases, such as COVID-19, spread through the transmission of aerosols and droplets. Aerosol and droplet formation occurs inside and outside of the respiratory tract, the latter being observed during speaking and sneezing. Upon sneezing, saliva is expelled as a flat sheet, which destabilizes into filaments that subsequently break up into droplets. The presence of macromolecules (such as mucins) in saliva influences the dynamics of aerosol generation, since elasticity is expected to stabilize both fluid sheets and filaments, hence deterring droplet formation. In this study, the process of aerosol formation outside the respiratory tract is systematically replicated using an impinging jet setup, where two liquid jets collide and form a thin fluid sheet that can fragment into ligaments and droplets. The experimental setup enables us to investigate a range of dynamic conditions, quantified by the relevant non-dimensional numbers, which encompass those experienced during sneezing. Experiments are conducted with human saliva provided by different donors, revealing significant variations in their stability and breakup. We quantify the effect of viscoelasticity via shear and extensional rheology experiments, concluding that the extensional relaxation time is the most adequate measure of a saliva's elasticity. We summarize our results in terms of the dimensionless Weber, Reynolds, and Deborah numbers and construct universal state diagrams that directly compare our data to human sneezing, concluding that the aerosolization propensity is correlated with diminished saliva elasticities, higher emission velocities, and larger ejecta volumes. This could entail variations in disease transmission between individuals which hitherto have not been recognized.

Epigenome is susceptible to modulation by environmental pressures—namely, through alterations in global DNA methylation, impacting the organism condition and, ultimately, reverberating on the phenotype of the subsequent generations. Hence, an intergenerational study was conducted, aiming to clarify the influence of genotoxicants on global DNA methylation of the crayfish Procambarus clarkii. Two subsequent generations were exposed to the herbicide penoxsulam (Px; 23 µg·L−1) and to the genotoxicant model ethyl methanesulfonate (EMS; 5 mg·L−1). Px did not induce changes in DNA methylation of adult crayfish (F0). However, the hypomethylation occurring in unexposed F1 juveniles demonstrated that the history of exposure per se can modulate epigenome. In F1 descendants of the Px-exposed group, methylome (hypermethylated) was more affected in males than in females. EMS-induced hypomethylation in adult females (F0), also showed gender specificity. In addition, hypomethylation was also observed in the unexposed F1 crayfish, indicating an intergenerational epigenetic effect. The modulatory role of past exposure to penoxsulam or to EMS also showed a dependency on the crayfish developmental stage. Overall, this research revealed that indirect experiences (events occurring in a predecessor generation) can have an impact even greater than direct experiences (present events) on the epigenetic dynamics.

Some engineering concepts have been proven to be very important not only in engineering degrees but in several areas. This knowledge is difficult to grasp under certain circumstances, and sometimes prior training is needed. This is a special challenge in full or part remote education. Simulations may help in this area, but truly experimental lab practices are crucial to grasp all the required knowledge and not only for fundamental information but for complex or indirect knowledge, where students can apply what they have learnt in classes. In this paper, we have worked on a concept to help professors and students to get new concepts in a more time-efficient and safe manner, using dynamic reconfiguration in Field-Programmable Analog Array. This solution can be easily applied to traditional or remote labs in less time than usual practices, so students can learn more in the same amount of time, especially when time is a constraint.

The employment of modern technologies is widespread in our society, so the inclusion of practical activities for education has become essential and useful at the same time. These activities are more noticeable in Engineering, in areas such as cybersecurity, data science, artificial intelligence, etc. Additionally, these activities acquire even more relevance with a distance education methodology, as our case is. The inclusion of these practical activities has clear advantages , such as (1) promoting critical thinking and (2) improving students’ abilities and skills for their professional careers. There are several options, such as the use of remote and virtual laboratories, virtual reality and gamebased platforms, among others. This work addresses the development of a new cloud game-based educational platform, which defines a modular and flexible architecture (using light containers). This architecture provides interactive and monitoring services and data storage in a transparent way. The platform uses gamification to integrate the game as part of the instructional process. The CyberScratch project is a particular implementation of this architecture focused on cybersecurity game-based activities. The data privacy management is a critical issue for these kinds of platforms, so the architecture is designed with this feature integrated in the platform components. To achieve this goal, we first focus on all the privacy aspects for the data generated by our cloud game-based platform, by considering the European legal context for data privacy following GDPR and ISO/IEC TR 20748-1:2016 recommendations for Learning Analytics (LA). Our second objective is to provide implementation guidelines for efficient data privacy management for our cloud game-based educative platform. All these contributions are not found in current related works. The CyberScratch project, which was approved by UNED for the year 2020, considers using the xAPI standard for data handling and services for the game editor, game engine and game monitor modules of CyberScratch. Therefore, apart from considering GDPR privacy and LA recommendations, our cloud game-based architecture covers all phases from game creation to the final users’ interactions with the game.

En este trabajo partimos de la fundamentación de las dos afirmaciones implícitas en el título: la existencia de la desglobalización y el unilateralismo como elemento característico de ésta. A partir de este marco conceptual y desde la hipótesis de la desglobalización como fenómeno, pasamos a mostrar algunos ejemplos que demuestran cómo el ámbito de la fiscalidad internacional es particularmente permeable a este tipo de prácticas dada su estrecha vinculación con la soberanía. Con este objetivo se exponen tres manifestaciones de carácter unilateral en el ámbito de la fiscalidad: El debate sobre la coloquialmente conocida como “tasa Google”, en el intento de construcción de un impuesto sobre servicios digitales hasta ahora infructuoso; el problema de la definición del concepto paraíso fiscal, en el que tampoco
existe acuerdo; y un esbozo sobre la situación en la Unión Europea. De esta forma tratamos de demostrar el tradicional pero creciente unilateralismo en el ámbito de la fiscalidad internacional. Todo ello asumiendo como método la heurística textual y la hermenéutica jurídica. De este modo, acentuamos el papel de la fiscalidad como herramienta clave en el proceso de desglobalización, su función proteccionista y geoestratégica, las dificultades existentes para lograr acuerdos en un ámbito que debe ser tenido en cuenta tanto por inversores privados como por Estados y su relevancia para la economía mundial. Como resultado consideramos justificado y fundamentado el uso del término “desglobalización”, así como su necesaria conexión con la fiscalidad internacional.

This paper studies the main determinants of the inbound international tourism in Andalusia and quantify its incidence. Based on the classical theoretical framework for tourism demand, we incorporate dynamics into the model by adding the lagged dependent variable as an explanatory variable, along with the per capita income of the tourist's country of origin, the relative prices between the origin and destination countries and the cost of travel. The empirical model is applied to a panel data set consisting of 21 countries of origin of the tourists for the period 2008–2018. Data were collected from the Hotel Occupancy Survey (HOS), published by the National Statistics Institute of Spain (INE). The results have been obtained using the GMM-DIFF estimator of Arellano and Bond. The parameters estimated reflect a high level of consumer loyalty and the importance of the word-of-mouth effect. Moreover, the income elasticity indicates that the demand for tourism in Andalusia may be considered as a luxury good. Prices have a negative relationship with tourism demand. The cost of travel, which has a negative effect, is statistically significant to explain the number of tourists' arrivals and, however, it is not significant for the overnight stays model.