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Vegetarian Diets and Their Effect on n‐3 Polyunsaturated Fatty Acids Status in Humans: Systematic Review
No full textVegetarian diets limit the consumption of foods of animal origin to a variable extent, potentially leading to deficiencies in specific nutrients, particularly proteins and n-3 polyunsaturated fatty acids (n-3 PUFA) from fish or seafood. This systematic review aimed to assess the impact of vegetarian diets on n-6 and n-3 PUFA status in humans, with a focus on critical periods such as pregnancy and growth. Studies were included if they evaluated the relationship between vegetarian diets and PUFA status with clearly defined vegetarian diet types and PUFA measurement methods. Exclusion criteria included systematic reviews, meta-analyses, and studies that included occasional meat or fish consumption. A comprehensive literature search was conducted in PubMed, Springer, and ScienceDirect databases, considering articles published up to 2023. A total of 45 studies were involved; the review found that vegetarian diets increased linoleic acid (C18:2 n-6, LA) and alpha-linolenic acid (C18:3 n-3, ALA) intake but resulted in significantly reduced concentrations of eicosapentaenoic acid (C20:5 n-3, EPA) and docosahexaenoic acid (C22:6 n-3, DHA), particularly in vegan diets. DHA intake from microalgae oil was shown to effectively improve serum DHA status, particularly during pregnancy and lactation. The evidence included in this review is limited by variations in study designs, potential biases in dietary reporting, and inconsistencies in PUFA (especially intake) measurement methods. These findings highlight the need for strict dietary planning and supplementation strategies to mitigate deficiencies, particularly during critical developmental periods
Beyond Technologies of Observation. Accepting Uncertainty in Disaster Risk Management
No full textThis short essay examines the current role of technologies of observation in disaster risk management, highlighting the limitations of relying solely on these systems to address extreme natural hazards. While advances in observation and prediction tools, such as seismographs, weather satellites, and early warning systems, have improved societies' capacity to anticipate and mitigate disasters, these technologies are not without challenges. Complex socio-technical systems remain prone to failures, and are difficult to interpret. Overall, uncertainty often prevails during emergencies. Using examples from Chile and Spain, this paper argues that the focus of disaster management should shift from the enhancement of technological precision to empowering decision-makers and communities to act effectively under conditions of uncertainty. I propose focusing on improving situational assessments, by emphasizing the importance of interpretation, translation, and even improvisation.FondecytFondecytANID Anillo de Ciencia y Tecnologí
El futuro de la esperanza: a 60 años de Teología de la Esperanza de Jürgen Moltmann
No full textEl presente artículo valora críticamente la vigencia de la obra Teología de la Esperanza de Jürgen Moltmann, después de 60 años de su publicación en 1964. Para ello, mediante el análisis sistemático de Teología de la Esperanza y otras referencias bibliográficas claves, (a) se consideran los antecedentes metodológicos previos de dicha obra; (b) se analiza su noción primordial Futuro de Cristo que otorga una clave transversal de lectura desde el futuro como adventus; y (c) se vislumbra la relevancia de la obra para la comprensión esperanza cristiana hoy como fuerza novedosa que brota incluso en las imposibilidades de la historia
Solvent-free mechanochemical access to phase-pure Cs-Co-Cl halometalates with tuneable electronic properties for energy applications
No full textWe report a solvent-free mechanochemical route for the selectively synthesis of three different caesium cobalt chlorides: CsCoCl3, Cs2CoCl4, and Cs3CoCl5, by simply tuning the CsCl : CoCl2 precursor ratio. This is the first comprehensive comparative study of these phases synthesized in pure form, enabling a clear correlation between composition, crystal structure, and optoelectronic properties. Each phase exhibits a unique Co2+ coordination geometry: octahedral in CsCoCl3 and tetrahedral in Cs2CoCl4 and Cs3CoCl5, as revealed by XRD, SEM-EDS, Raman, and XPS, with several features reported here for the first time. All phases display high thermal stability and narrow optical bandgaps (1.65-1.70 eV), supported by ligand field analysis and CIE colorimetry. Valence and conduction band energies determined by VB-XPS and cyclic voltammetry reveal a systematic, composition-driven tuning of energy levels across the series. Importantly, the band edge alignment are suitable for visible-light-driven hydrogen evolution and photovoltaic applications. SCAPS-1D simulations predict power conversion efficiencies up to 17.1%, positioning these halocobaltates as promising absorbers. Altogether, this work introduces a scalable synthesis route and demonstrates the potential of cobalt-based halide frameworks as modular systems for solar energy conversion and photocatalysis
Algoritmo de cálculo para estimar el rendimiento higrotérmico de la vegetación en fachadas de pantalla verde
No full textEl uso de plantas como protección solar está ganando interés debido a los múltiples beneficios del material vegetal, en contraste con los protectores solares convencionales. Sin embargo, su aplicación y estudios están actualmente limitados por la complejidad de considerar variables orgánicas como parte de su rendimiento en relación con un contexto climático. Estas limitaciones son evidentes en los softwares de simulación digital, los cuales no permiten cuantificar los beneficios térmicos que distinguen esta protección de las convencionales en simulaciones de balance energético. Este trabajo presenta un método para evaluar el potencial de enfriamiento de fachadas de pantalla verde que permite al modelo diferenciar y medir el efecto de las fachadas de pantalla verde como dispositivo de sombreado y como estrategia de enfriamiento evaporativo. Para ello, se desarrolla un modelo higrotérmico integrando modelos de cálculo proporcionados por varios autores dentro de la plataforma Grasshopper usando los motores de simulación EnergyPlus. Los resultados muestran que es posible simular el comportamiento térmico virtual del material vegetal, incorporando la evapotranspiración de la planta y sus propiedades en el cálculo de las demandas de aire acondicionado de los edificios.
Trainees and Consultants: Which are the Best Teaching Options in Surgery?
No full textESCALA (Estudio de Salud y Contaminación del Aire en Latinoamérica) is a study that examines the association between outdoor air pollution (PM10 and O3) and health effects in Brazil, Mexico and Chile, in all causes, all ages mortality and in subgroups defined by cause, age and gender. We report the results for Santiago, a 5 M people city, Concepcion, a 600,000 people industrial city, and Temuco, a city of 360,000 people dominated by wood-burning pollution in winter. Poisson regression was used to fit a model to the time-series data (1997–2005), adjusting for seasonality and meteorology. Distributed lag models were fitted considering a 2nd degree polynomial with exposure lagged up to 5 days. In Santiago, in most of the age groups and causes studied, PM10 had a signficant impact on daily mortality. The risk percentage change (RPC) for 10 μg/m3 PM10 ranged from 0.12% (cardiopulmonary, all ages) to 0.46% (respiratory, all ages). Ozone also had significant impacts for all causes, cardiopulmonary causes. The biggests effects were found for cerebrovascular/stroke (CEV) deaths (RPC 0.56 to 0.66 for all ages and elder). The only significant effects in Concepcion were found for the elder population for respiratory causes (RPC 1.65%) and COPD (RPC 2.6 to 2.9%). In Temuco, COPD had the higher risk for the whole population (RPC 2.7 to 4%) and CEV also had a high risk (RPC 1.2 for all ages, 1.1 to 1.5 for elder). These results provide further evidence of the adverse health effects of PM10 and O3 in cities of the developing world. The higher effects were found for two relatively small cities, with different mixtures of air pollution. Possible differential effects by socioeconomic characteristics of the exposed populations may explain much of the differences and are being currently investigated
Analysing the trends of research contributions and scientific collaboration networks working in Antarctic science: a look to the production of the Spanish programme honouring the memory of Andrés Barbosa
No full textAntarctica, which has always been of great interest to researchers worldwide, is currently attracting considerable attention owing to climate change and other topics. In this context, bibliometric analysis allows the identification of hot topics, scientific productivity, cooperation, research gaps and strategic areas of potential interest. We conducted a bibliometric study to evaluate the global production of Antarctic research between 1980 and 2023 and analysed Spanish National Antarctic Programme (NAP) production as a case study. Scientific publications were reviewed and classified based on their main themes, key word co-occurrence and international collaborations. We found that scientific production worldwide and in the Spanish NAP has progressively increased since 1980. Globally, the main areas of research are the geosciences, oceanography and atmospheric sciences. However, the Spanish NAP, which reported 2287 publications, has focused more on the geosciences and ecology. Spanish Antarctic researchers have mainly collaborated with researchers from the USA, the UK, Germany and Italy. Our research highlights the importance of strengthening research plans to diversify and facilitate international collaboration, promoting a more interdisciplinary approach to address the current and future challenges identified by the scientific community. In this context, specific opportunities for developing a Spanish NAP strategic plan are discussed
Descripción acústica de las vocales del mapudungun
No full textEl mapudungun es una lengua indígena hablada en el sur de Chile y Argentina, cuyo sistema vocálico aún presenta aspectos por explorar desde la perspectiva acústica. Este artículo tiene como objetivo describir acústicamente las seis vocales del mapudungun hablado en Chile. Para ello, se analizaron las grabaciones de 31 hablantes (17 mujeres y 14 hombres), provenientes de las regiones del Biobío y La Araucanía. Se obtuvieron los valores de los formantes (F1, F2 y F3) para cada vocal y se compararon con los valores de referencia para el castellano chileno. Los resultados muestran que las cinco vocales compartidas con el castellano presentan diferencias significativas en su realización acústica, aunque parecen ser más próximas al castellano de Chile que a otras variedades. En cuanto a la llamada “sexta vocal” /ɯ/, los resultados la sitúan como una vocal posterior distinta de /u/, ubicada en una posición ligeramente más baja en el espacio vocálic
Fault intersection-related stress rotation controls magma emplacement at the Nevados de Chill´ an Volcanic Complex
No full textIt has been suggested that fracture and fault intersections promote enhanced transport of fluids in the brittle crust by forming zones of increased permeability. However, the underlying mechanisms that control the emplacement of magma at fault intersections remain poorly understood. To better understand the relation between magma emplacement, volcano development and fault zone intersections, we examine the Nevados de Chillán Volcanic Complex (NChVC, 36.8°S) in the Southern Andean Volcanic Zone. The complex is thought to be located atop the intersection between two sets of NE-right lateral strike-slip faults and a seismically active regional scale NW-oriented inherited structure, also interpreted as a regional fault zone. We collected data on the orientation and frequency of tens of dykes and thousands of fractures, at the volcano scale, from representative outcrops using three-dimensional digital image correlation techniques, with images taken from Unmanned Aerial Vehicles (UAVs). We use these data to generate a conceptual model of the response of the different fracture sets to regional loads and the potential consequence in terms of magma emplacement. In our conceptual model, N-S to NW-SE striking fractures become reactivated by fault intersection-related local stress field rotations. This, in turn, favors NW-SE aligned magma emplacement, and the evolution of NW-SE aligned volcanoes. Our findings provide a mechanical explanation for rotated magma emplacement pathways, which do not necessarily require a transient stress state imposed by unlocking the megathrust
Tree‐Cavity Denning of Güiña (Leopardus guigna) and Breeding Productivity From Camera Trap Records
No full textTree cavities are critical habitats for numerous vertebrate species, serving as keystone resources for nesting, roosting, and shelter.We document the first evidence of an individual güiña (Leopardus guigna) breeding within a tree cavity of a standing dead tree.We explore its implications on breeding productivity and complementing this record with evidence from camera trap surveysconducted in temperate forests of south-central Chile. These findings enhance our understanding of the species' natural history,breeding behavior, and habitat preferences. Additionally, we discuss the conservation implications of this discovery, offering newinsights into the breeding ecology and habitat selection of one of South America's most elusive felines