Universidad Católica de la Santísima Concepción

Abstract We report a multi-epoch V-band campaign (2021–2023) with uniform processing and a common 550 km normalisation across Starlink generations. Median magnitudes (68% confidence intervals; N in brackets) are: v1.0: 5.365,[5.084,5.553] (34), Gen-2: 6.012,[5.801,6.173] (6), v1.5: 6.106,[6.065,6.154] (164), VisorSat: 6.618,[6.403,6.804] (54), DarkSat: 8.431,[5.916,10.947] (2). This yields the ordering v1.0 < Gen-2 ≲ v1.5 < VisorSat ≪ DarkSat, i.e. mitigation-era designs are typically fainter than the original v1.0. The Gen-2–v1.5 difference is small (0.094,mag) and Gen-2 has limited coverage (N = 6), so the trend is not strictly monotonic. We use an open, Python-based processing pipeline built on astropy for standard image calibration (bias, dark and flat-field correction), astrometric and photometric calibration against Gaia DR3, and derivation of the viewing geometry (solar phase angle, range, elongation and airmass). Satellite tracks are identified from TLE-based ephemerides, matched to the detections, and then used to measure a brightness value for each track in a reproducible way. At a common height, the medians are 5.37 (v1.0), 6.01 (Gen-2), 6.11 (v1.5), 6.62 (VisorSat) and 8.43 (DarkSat; N = 2), which are ∼0.4–1.6 mag brighter (numerically smaller) than the target of V ≈ 7. Thus, mitigation shows clear progress but does not yet meet the IAU CPS/SATCON goal of V ≥ 7 at ∼550 km. These benchmarks can guide future satellite designs, survey planning and avoidance strategies, with the main uncertainties arising from the very small samples for DarkSat and Gen-2.

Living on Chilean islands with limited connectivity presents considerable challenges for accessing in-person healthcare services, particularly in medical specialties and emergencies. The Telemedicine and Telehealth Regional Center of Biobío proposed innovative and participatory interventions involving local and mainland health ecosystem stakeholders. Addressing educational, technological, organizational, and community awareness challenges requires gathering information from health centers and communities to identify gaps and propose solutions tailored to local needs and capabilities. To address these challenges, we enabled satellite internet, coordinated actions with decision-makers, trained local health teams, and raised awareness among the population about the advantages and limitations of telemedicine. This innovation is part of a collaborative model that links academia, health centers, and government support, and it is framed in three theoretical models: The b-Health 2.0, The Community Engagement model, and the Primary Care–Oriented Digital Health approach. The result was an increase in care visits, improved case resolution, and access to specialist physicians and electronic medical records. It improved the digital skills of health personnel for their work. This initiative validates that telemedicine is a valuable tool in island settings and allows for its replication in other territories.

The rapid digital transformation of education systems has profoundly changed teachers' working conditions, intensified administrative demands, and highlighted territorial and organizational inequalities. In this context, understanding how these dynamics influence teacher engagement is essential for promoting healthy educational organizations. This study examined the factor structure of the UWES-17 and analyzed the relationship between engagement levels and sociodemographic variables in a sample of 314 elementary school teachers from four regions of Chile. Descriptive analyses, exploratory factor analysis with polychoric correlations and unweighted least squares, and confirmatory factor analysis using robust ULS and the Hull method were performed. The results showed a robust two-factor structure-Inspired Vitality and Challenging Commitment-with excellent fit indices. Freeman-Halton exact tests showed that Inspired Vitality was significantly associated with age, gender, region, location, administrative dependency, and professional experience, while Challenging Commitment was associated with gender, region, context, and professional experience. These findings indicate that teacher engagement is influenced by both structural inequalities and individual trajectories. The results underscore the need to strengthen organizational resources, regulate digital intensification, and reduce territorial gaps to promote teacher well-being.

El estudio examina el desarrollo del documental interactivo en Chile, centrado en las experiencias de la Región de Valparaíso entre los años 2021 y 2024. A través de una metodología mixta, que combina matrices cuantitativas y análisis cualitativo, se abordan cinco casos de producciones que abordan temáticas sociales, medioambientales, históricas y territoriales, mediante el uso de tecnologías inmersivas como la realidad aumentada y el video 360, integrando interacciones digitales y análogas con las audiencias. Se identifican así, patrones que vinculan la innovación tecnológica, la identidad comunitaria y la participación colaborativa para cada caso. Los resultados subrayan el rol clave de las universidades en la creación de estas obras, y la colaboración interdisciplinar en la consolidación de un modelo audiovisual propio con identidad regional. Se concluye que el documental interactivo chileno, es una herramienta poderosa para promover la inclusión territorial y la producción digital en Latinoamérica.

Physical exercise is a potent non-pharmacological strategy for the prevention and management of Metabolic dysfunction-associated steatotic liver disease (MASLD), a multifactorial disorder characterized by hepatic lipid accumulation, insulin resistance, oxidative stress, and chronic inflammation. Emerging evidence demonstrates that the benefits of exercise extend beyond caloric expenditure and are largely mediated by coordinated molecular and cellular adaptations within the liver and peripheral tissues. This review synthesizes current knowledge on the mechanisms through which exercise modulates MASLD pathophysiology, emphasizing intracellular signaling pathways, mitochondrial remodeling, antioxidant defenses, and myokine-driven muscle-liver crosstalk. Exercise induces acute and chronic activation of pathways such as AMPK, PGC-1α, Nrf2, and Akt, resulting in enhanced mitochondrial biogenesis, improved fatty acid oxidation, restored insulin signaling, and reduced inflammatory and oxidative stress. Repeated skeletal muscle contraction stimulates the release of myokines-including irisin, IL-6, and FGF21-that act through endocrine and paracrine routes to regulate hepatic lipid metabolism, promote systemic metabolic flexibility, and attenuate disease progression. Epigenetic modifications and exercise-responsive microRNAs further contribute to long-term hepatic metabolic reprogramming. Collectively, these molecular adaptations position exercise as a systemic, disease-modifying stimulus capable of restoring hepatic homeostasis, slowing the transition from steatosis to NASH and fibrosis, and improving long-term metabolic health. Understanding these mechanisms provides a foundation for developing targeted, personalized exercise-based interventions in the clinical management of MASLD.

ABSTRACT Subduction megathrust events dominate seismicity in Chile, leading to a less comprehensive understanding of the hazard posed by crustal faults. One such source is the San Ramón fault (SRF), a potentially active fault at the eastern border of the Metropolitan Region of Santiago. This study assesses the seismic performance of three modern hospitals seismically isolated with high damping rubber bearings, located 7–24 km from the SRF trace. Their responses were evaluated using nonlinear 3D finite element models subjected to a suite of 432 synthetic ground motions. To account for the uncertainty in the seismogenic capacity of the SRF, these physics‐based simulations systematically vary key source parameters, including event magnitude, average rupture velocity, and corner frequency. For facilities near the fault, the results show critical performance failures. Isolation systems are prone to pounding as displacements exceed their design limits, while large vertical accelerations cause a high probability of tensile forces in the bearings. Furthermore, interstory drifts and floor accelerations in the superstructures exceed the thresholds required to maintain continuous operation. These findings reveal that even the new generation of seismically isolated hospitals is critically vulnerable to near‐fault crustal earthquakes if not explicitly designed for them. This unaccounted‐for seismic hazard highlights an urgent need for comprehensive risk re‐assessment and the development of targeted mitigation strategies in Santiago and other cities facing similar hazards.

Este artículo busca identificar y analizar imaginarios y representaciones sociales que docentes universitarios/as en Colombia configuran sobre la educación superior en el contexto de la pandemia y la postpandemia por COVID-19, considerando la persistencia de sus efectos pedagógicos y socioemocionales en el escenario educativo actual. Desde un enfoque cualitativo de carácter exploratorio-interpretativo, se analizaron 18 entrevistas semiestructuradas realizadas a docentes de instituciones públicas y privadas de distintas regiones del país, seleccionados de manera intencional. El análisis permitió identificar cuatro dimensiones: elementos formativos resignificados, respuestas institucionales, afectaciones estudiantiles y proyecciones del modelo educativo. Los resultados, circunscritos al contexto y a las experiencias de los participantes, evidencian una revalorización de la humanización de la enseñanza, la integración de la dimensión socioemocional y la flexibilización metodológica. Asimismo, emergen imaginarios que proyectan una educación más ética, situada, relacional y multimodal, orientada no solo a la transmisión de contenidos, sino al sostenimiento de la vida en contextos de incertidumbre.

This article summarizes our research on integrated timber investment returns, wood stumpage costs, and forest carbon production costs in 2023 for a representative selection of 15 countries, across 44 planted and 1 natural species/management regimes, using capital budgeting criteria, at a real discount rate of 8%, without land costs. Despite a large amount of disparate research, few, if any, studies have provided integrated estimates of investments, wood fiber costs, and forest carbon costs for CO2 offsets using fundamental primary data and production economics approaches. We expanded our prior research that estimated present values and internal rates of return for timber investments, using planted forest growth and yield, input management costs, and timber products prices by selected countries and species. We extended the production economics and forest investment calculations to estimate average stumpage costs for wood fiber per cubic meter per rotation. In addition, we calculated the costs to produce forest carbon for offsets in terms of carbon dioxide equivalent. Timber investment returns by country and species were the largest in tropical Asia and smallest in the Northern Hemisphere (including the United States and Europe), and South America had calculated returns between the two regions. Based on prior research, more developed countries had less investment risk, and had land markets that were more open for foreign investments. Wood costs and forest carbon production cost outcomes by country and species differed substantially from timber investment returns. The discounted wood costs per m3 were generally cheapest if the establishment costs and management inputs were minimized, or for long rotation planted stands. Forest carbon costs had similar rankings to wood costs, and even similar numbers, but were using a different metric—dollars per tCO2e. The calculated forest carbon costs are certainly among the cheapest of all types of typical carbon offsets. They were equal to or much less than the six primary developed country compliance market prices. However, they were higher than the current depressed public voluntary market prices. These results can be used for private, government, or nongovernment investments and for public policy intervention considerations.