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The Spin–Orbit Alignment of Eight Warm Gas Giant Systems
No full textEssential information about the formation and evolution of planetary systems can be found in their architectures—in particular, in stellar obliquity (ψ)—as they serve as a signature of their dynamical evolution. Here we present ESPRESSO observations of the Rossiter–McLaughlin (RM) effect of eight warm gas giants, revealing that, independently of the eccentricities, all of them have relatively aligned orbits. Our five warm Jupiters (WASP-106 b, WASP-130 b, TOI-558 b, TOI-4515 b, and TOI-5027 b) have sky-projected obliquities |λ| ≃ 0–10°, while the two less massive warm Saturns (K2-139 b and K2-329 A b) are slightly misaligned, having |λ| ≃ 15–25°. Furthermore, for K2-139 b, K2-329 A b, and TOI-4515 b, we also measure true 3D obliquities ψ ≃ 15–30°. We also report a nondetection of the RM effect produced by TOI-2179 b. Through hierarchical Bayesian modeling of the true 3D obliquities of hot and warm Jupiters, we find that around single stars warm Jupiters are statistically more aligned than hot Jupiters. Independent of eccentricities, 95% of the warm Jupiters have ψ ≲ 25° with no misaligned planets, while hot Jupiters show an almost isotropic distribution of misaligned systems. This implies that around single stars warm Jupiters form in primordially aligned protoplanetary disks and subsequently evolve in a more quiescent way than hot Jupiters. Finally, we find that Saturns may have slightly more misaligned orbits than warm Jupiters, but more obliquity measurements are necessary to be conclusive
Selective benzaldehyde/acetone to benzalacetone cross-aldol condensation catalyzed by UiO-66 MOFs
No full textCross-aldol condensation reactions are an important family of reactions that generate added-value chemicals with long chain products. Those products have multiple applications, such as those in the pharmaceutical industry, flavors and fragrances, agricultural chemicals and fine and specialty chemicals, among others. Possible products are long chain aromatic compounds, which could be used to generate fuels. The ability to generate that kind of fuel from biomass has been a challenge over the last few years. In this report the cross-aldol condensation reaction study using a family of UiO-66 MOFs between benzaldehyde and acetone to produce benzalacetone was performed. Thus, a family of UiO-66 MOFs was synthesized and characterized (by means of N2 physisorption, NH3-TPD, CO2-TPD, ATR-FTIR, and powder X-ray diffraction) and its catalytic activity was studied in detail. Good conversion and selectivity were obtained. A thorough study of the kinetics of this reaction was performed for all the used UiO-66 MOFs. In this sense, the Langmuir–Hinshelwood kinetic models fitted the experimental data. The behavior predictions using different metals (Zr, Hf or Zr/Hf) and linkers (BDC or PDC) were fitted from the bimolecular one-site and two-site models. Competitive and non-competitive mechanisms were used to explain the production of the main intermediate compound (β-hydroxy ketone). The catalyst Zr/Hf-UiO-66 showed the best activity, which could be attributed to the greater total interaction energy of benzaldehyde/acetone on the catalyst surface (as shown by DFT calculations). A synergetic effect is observed for the bimetallic UiO-66 catalyst between Zr and Hf, obtaining a higher reaction rate than for the monometallic catalysts. Furthermore, a similar effect was reflected in the TOF for Zr/Hf-UiO-66. The best selectivity towards benzalacetone was obtained for Hf-UiO-66-PDC under iso-conversion conditions. Finally, depending on the metal–linker pair, differences in the benzaldehyde/acetone adsorption modes were observed, indicating the presence of bimolecular kinetic adjustments at one and two sites for the aldol condensation of benzaldehyde. All the results shown herein were supported by means of DFT calculations
Equilibrium states and asymptotic variance for geometric potentials
No full textTesis (PhD in Mathematics)--Pontificia Universidad Católica de Chile, 2025En esta tesis abordamos tres problemas dentro del marco del formalismo termodinámico. En primer lugar, estudiamos el espectro de Lyapunov de las aplicaciones de Markov-Rényi-Lüroth en el intervalo, una familia de aplicaciones de intervalo de tipo Markov numerables que pueden presentar simultáneamente puntos fijos parabólicos y una discontinuidad en la presión topológica asociada al potencial geométrico. En segundo lugar, investigamos la existencia de estados de equilibrio para una familia de aplicaciones monótonas a trozos con convexidad promedio. Estas aplicaciones pueden tener puntos fijos parabólicos, particiones no Markovianas y un potencial geométrico que no es necesariamente Hölder continuo. Finalmente, analizamos la varianza asintótica para transformaciones abiertas, topológicamente transitivas y expansivas en espacios métricos compactos. Proporcionamos nuevas cotas para las diferencias en desigualdades de media potencia para potenciales Hölder continuos, expresadas en términos de la varianza asintótica.ANI
Nitric oxide reduction and pulsatile flow during cardiac surgery with cardiopulmonary bypass: Is it really the cause?
No full text© 2025, Universidad Pontificia Bolivariana. All rights reserved.Henri de Lubac's intellectual journey is interwoven with the issue of mysticism. Motivated by the contemporary crisis of the Church and society in the 20th century, he turns to mysticism, exploring its possibilities in a context of profound cultural transformations and a weakening of faith. His "unfinished" reflection on mysticism shows evolutions, and in its most refined stage, it is connected to the spiritual intelligence of the Scriptures, with a distinctly anthropological and ecclesial character. This article seeks to explore the complex relationship Lubac has with the question of mysticism, shaped by the aftermath of the modernist crisis and the "trauma" caused by the crisis of the Nouvelle Théologie and the Jesuit faculties of Fourvière. To this end, the author's reflections are incorporated into theological and philosophical debates on mysticism, particularly in dialogue with the thought of his disciple Michel de Certeau
Franz Kafka, ¿a letter without psychoanalysis?
No full text© (2025), (Universidad de Concepcion). All rights reserved.The goal of this article is to explore Kafka’s relationship with psychoanalysis in one of his most biographical texts, Letter to the Father, and the effects that Kafka’s literary imagination has had on the interpretation of modern subjectivity by contemporary philosophers. Establishing relations between Kafka and the readings of this author by Hans Blumemberg, Theodor Adorno, Maurice Blanchot, Giorgio Agamben and Elias Canetti, among others, the article proposes that Kafka is a post-psychoanalytic or post-oedipal writer insofar as he makes literature a space without illness or cure.Agencia Nacional de Investigación y Desarrollo-ANIDConcrete Innovation Hub UCFONDECYTFONDECY
Vega González e Outros vs. Chile: Coisa Julgada e Implementação Convencional
No full textEste artículo examina la cosa juzgada nacional e internacional, así como la implementación de las sentencias de la Corte Interamericana de Derechos Humanos (Corte IDH) por parte del Estado condenado bajo la Convención. Para ello, analizamos dos de las obligaciones establecidas por la corte internacional en el caso Vega González y otros vs. Chile : la revisión de las sentencias definitivas en el ámbito interno, con un control de convencionalidad; y la adecuación del derecho nacional a la decisión de la Corte Interamericana de Derechos Humanos y la implementación de su sentencia bajo esta revisión, a la espera de una reforma legislativa. Por lo tanto, examinamos: cómo ha reaccionado el Estado de Chile ante la revisión de las sentencias internas ordenadas por la Corte Interamericana de Derechos Humanos en otros casos similares; qué otras opciones de cumplimiento están disponibles para los Estados condenados por este tribunal internacional en casos similares; y la aplicación del control de convencionalidad a las reparaciones ordenadas por la Corte Interamericana de Derechos Humanos en el caso Vega González y otros vs. Chile , explorando la distinción entre cosa juzgada internacional y control de convencionalidad según lo establecido en la jurisprudencia de la Corte Interamericana.This article is aimed at studying national and international res judicata, and the conventional implementation of the Inter-American Court of Human Rights’ (lACtHR) judgments, by the condemned state. To this end, we analyse two of the obligations ordered by this international court, in the Vega González and others v. Chile case: the revision with control of conventionality of internal final judgments, on the one side; and the duty to adapt national law to the lACtHR’s decision and to implement it applying such control, until the correspondent legal reform is enacted, on the other. Hence, we examine: how has Chile reacted to the revision of internal judgments, ordered by the lACtHR in other cases in which that state has appeared before it; other available options for states condemned by the lACtHR in similar cases; and the application of conventionality control to the reparations ordered by this international court in the Vega González and others v. Chile case, exploring the distinction between international res judicata and control of conventionality made by the lACtHR in its case-law
Channel Access Probability in Unslotted IEEE 802.15.4 csma Under Correlated Clear Channel Assessments
No full textCorrelation between successive clear channel assessments in unslotted carrier sense multiple access with collision avoidance (CSMA/CA) is commonly assumed in the literature to be negligible for modeling the medium access control algorithm. However, in previous research, the authors found this assumption to be questionable under certain realistic conditions. In this paper, the correlation between successive clear channel assessments is studied and its effect on the probability and delay of accessing the medium by a node following the IEEE 802.15.4 Standard is modeled for the unslotted CSMA/CA mode. The results obtained are used for evaluating the delay probability distributions of the three outcome events of the CSMA/CA algorithm: frame transfer success, channel access failure and frame transfer failure. For scenarios in which the duration of contentions is similar to, or shorter than, the duration of the frames propagating in the air, the correlation effect is strong, making classical models to yield results that deviate from a realistic scenario. The theoretical results are validated by simulations. It is shown that neglecting correlation between successive clear channel assessments leads to overestimating the expected delay of frame transfer success and channel access failure by up to 15%. The results also reveal that the probability of frame transfer success can be overestimated by up to 30%, the probability of frame transfer failure by up to 80% and the probability of channel access failure is underestimated by up to a factor 6 when clear channel assessment correlation is ignored
Self-Regenerative Mo-Based Solid Lubricant Coatings Deposited by APS as a PVD Alternative: Mechanical and Tribological Performance
No full textSolid lubricant coatings are essential for reducing friction and wear in tribo-mechanical systems, particularly in environments where traditional liquid lubricants can’t be used or fail. It has been reported in literature that self-regenerating physical vapor deposition (PVD) coatings can be designed in such a way that they continuously release MoO3 as a solid lubricant through tribo-oxidation. However, a disadvantage of PVD coatings is the limited layer thickness of just a few micrometers and thus the limited solid lubricant reservoir. In contrast, atmospheric plasma spraying (APS) allows the deposition of thicker reservoir layers, potentially extending service life under tribological stressing. Therefore, the aims of this study are to determine whether APS coatings with regenerative properties can be deposited on bearing steel and to assess their tribological performance. The mechanical, tribological, and structural behavior were analyzed using microindentation, ball-on-plate tribometer testing under dry conditions, optical and laser scanning, scanning electron microscopy (SEM), and energy-dispersive x-ray spectroscopy (EDX). Despite the relatively low hardness of the APS coating, excellent wear resistance protection was demonstrated at various loads and sliding velocities. Additionally, EDX analyses revealed that abrasive wear was prevented and a protective film was formed through tribo-oxidation, effectively shielding the surfaces. The results thus indicate the effectiveness of the APS coating and underline its potential for large-scale machine elements, such as rolling bearings
Hacia una bioeconomía sostenible: Revisión de biodiésel y bio-etanol en la década 2015-2025
No full textEste artículo presenta una revisión crítica de los avances en tecnologías, sostenibilidad y marcos regulatorios relacionados con la producción de biodiésel y bioetanol en el período 2015–2025. El análisis integra literatura científica revisada por pares, patentes y reportes técnicos internacionales, evaluando materias primas, procesos convencionales y emergentes, así como sus impactos ambientales y económicos. Los resultados muestran que, aunque las tecnologías de primera generación (transesterificación de aceites y fermentación de azúcares) alcanzan altos rendimientos, su dependencia de cultivos alimentarios plantea desafíos en seguridad alimentaria y uso de suelos. En contraste, los biocombustibles de segunda generación basados en residuos y biomasa lignocelulósica han demostrado potenciales ahorros de emisiones de gases de efecto invernadero del 50–90 %, pero su escalamiento sigue limitado por costos tecnológicos y la necesidad de marcos regulatorios estables. La discusión resalta que el rol de biodiésel y bioetanol debe entenderse como complementario dentro de la transición energética, con aplicaciones estratégicas en sectores difíciles de electrificar (aviación, transporte marítimo, carga pesada) y en regiones donde aportan seguridad energética y desarrollo rural. Las conclusiones recomiendan fortalecer la investigación en catalizadores, pretratamientos y biotecnología microbiana; promover biorrefinerías integradas; actualizar regulaciones con metas específicas para biocombustibles avanzados; y mejorar la trazabilidad mediante certificaciones robustas. De esta manera, se sientan las bases para que biodiésel y bioetanol contribuyan de manera significativa a la descarbonización hacia 2050
Incorporating machine learning in search and planning problems
No full textTesis (Doctor in Engineering Sciences)--Pontificia Universidad Católica de Chile, 2025La busqueda heurística es un método universal de resolución de problemas y es el núcleo de la planificación automática. La búsqueda ofrece propiedades teóricas como la completitud y las garantías sobre la calidad de la solución, como la w-optimalidad. Si bien el aprendizaje automático (ML) ha logrado un éxito notable en dominios como la clasificación de imágenes y el procesamiento del lenguaje natural, su aplicación a la búsqueda y la planificación automática presenta desafíos significativos. Los enfoques existentes comúnmente comprometen las propiedades teóricas de los algoritmos de búsqueda tradicionales, lo que destaca la necesidad de nuevos métodos que combinen la adaptabilidad del ML con la confiabilidad de las técnicas basadas en búsqueda. Esta tesis explora cómo los modelos y métodos de ML se pueden integrar de manera efectiva en los problemas de búsqueda para mejorar la eficiencia y la escalabilidad sin sacrificar sus propiedades teóricas. Esta tesis aborda tres preguntas de investigación: (1) ¿Cómo se pueden incorporar las heurísticas y políticas aprendidas en los algoritmos de búsqueda manteniendo las garantías de suboptimalidad? (2) ¿Cómo puede el procesamiento por lotes basado en GPU acelerar el cálculo de las heurísticas aprendidas sin comprometer estas garantías? (3) ¿Cómo pueden los modelos simbólicos parcialmente especificados mejorar el rendimiento de los algoritmos de búsqueda utilizando heurísticas o políıticas basadas en ML? Entre las contribuciones se incluyen el desarrollo de Focal Discrepancy Search (FDS), un algoritmo de búsqueda acotado por suboptimalidad que integra heurísticas aprendidas al tiempo que conserva las garantías teóricas y K-Focal Search, un método acelerado por GPU que mejora la eficiencia de la búsqueda y proporciona soluciones w-optimas. Además, este trabajo presenta un nuevo marco que combina modelos simbólicos parciales con enfoques basados en ML, lo que permite soluciones más escalables y eficientes para tareas de toma de decisiones secuenciales.ANI