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Neonatal anthropometry outcomes comparing two gestational weight gain standards
No full textObjectives: The gestational weight gain chart published by Rosso and Mardones (RM) was used by the Ministry of Health in Argentina from the 1990s until 2009, when it was replaced by the Calvo et al. chart (CEA). This study compared the diagnostic capability of the RM and CEA charts for identifying mothers at risk of delivering babies with signs of intrauterine growth impairment (Birth length4000 g).Methods: Data from pregnant women and neonates studied in Santiago, Chile (n = 27,600), as well as a sub-sample of 11,465 term healthy singleton cases were utilized. Frequency distributions of women and their 95% confidence intervals were calculated for both charts at the first and third trimester of pregnancy. Sensitivity, specificity, positive and negative predictive values of undesirable outcomes of the RM and CEA charts were compared.Results: The CEA chart classified as either underweight or obese a smaller number of women than the RM chart. The proportion of neonates with signs of intrauterine growth impairment was similar in both charts, however the number of affected neonates was higher in the women considered to be either underweight or obese by the RM chart. Higher sensitivity values for undesirable outcomes were displayed by the RM chart. The sum of sensitivity and specificity was also higher for the RM chart, meaning a greater diagnostic accuracy; this sum was comparable only for birth weight <2500 g. The RM chart was found to have higher positive and negative predictive values for undesirable outcomes than the CEA chart.Conclusion: The RM chart has a better diagnostic capability than the CEA chart to identify mothers at risk of delivering babies with signs of intrauterine growth impairment
Bajo el agua y sobre el patrimonio: Centro Recreacional y de Bienestar Maestranza San Bernardo
No full textTesis (Arquitecto con Magíster en Arquitectura)--Pontificia Universidad Católica de Chile, 2024La investigación se centra en la Maestranza Central de San Bernardo (MCSB) y su potencial para ser reusada y revalorizada como un nuevo centro urbano recreacional y de bienestar en la ciudad de San Bernardo. En particular, se busca abordar la falta de espacios recreativos y la carencia de infraestructuras adecuadas para el esparcimiento de la comunidad local, aprovechando la riqueza histórica y simbólica del edificio, su gran escala y su ubicación estratégica. El estudio considera el proceso de revitalización de la MCSB como un reto para integrar de manera armónica nuevas funciones sociales sin perder de vista su patrimonio cultural e industrial.La propuesta se materializa en un centro acuático recreacional y de bienestar, que busca responder a la marcada escasez de piscinas públicas tanto a nivel metropolitano como en la comuna de San Bernardo. Este programa busca ofrecer un espacio accesible para la comunidad, orientado a mejorar la calidad de vida mediante actividades recreativas, de ocio y de bienestar físico y mental.El análisis teórico y práctico de distintos ejemplos arquitectónicos ha permitido comprender cómo otros proyectos similares han abordado el reúso de edificaciones históricas con el fin de adaptarlas a nuevos usos. En particular, se ha explorado el concepto de “ocio” y “bienestar” que surge en espacios como las termas romanas, las termas de Vals de Peter Zumthor, o el proyecto del SESC Pompeia en Brasil. Estos casos proporcionan una visión de cómo la arquitectura puede articular espacios que promuevan no solo el descanso, sino también la interacción social, la cultura y el bienestar físico y mental. De estos precedentes, se extraen lecciones clave sobre la relación entre espacio y experiencia, y sobre la posibilidad de transformar la MCSB en un centro de actividades y recreación que sea accesible y relevante para la comunidad contemporánea de San Bernardo.El desafío principal en este proyecto radica en cómo adaptar los valores funcionales, sociales y estéticos que ofrece la MCSB a la visión contemporánea del ocio y la recreación, sin perder el respeto por su identidad histórica. A través de una serie de propuestas de intervención arquitectónica, se pretende consolidar la MCSB como un nuevo centro urbano que, además de promover actividades recreativas y culturales, potencie el bienestar social, la integración comunitaria y el desarrollo urbano sostenible en la comuna.En resumen, este trabajo busca ofrecer una reflexión sobre el reúso arquitectónico y el valor de los espacios históricos, en particular en el contexto de la MCSB, con el objetivo de proponer un proyecto que articule estos valores a través de una intervención respetuosa pero innovadora, destinada a mejorar la calidad de vida de los habitantes de San Bernardo
Transport mechanisms of the anthropogenic contaminant sulfamethoxazole in volcanic ash soils at equilibrium pH evaluated using the HYDRUS-1D model
No full textThe volcanic soils in Chile, where a significant portion of agricultural activities take place, are impacted by the presence of veterinary drugs, including sulfamethoxazole (SMX). The study examines how different soil types influence the movement and retention of sulfamethoxazole (SMX) across four regions of Chile, focusing on conditions at a neutral pH of 7.0. Collipulli's Ultisol soils (CLL), characterized by high clay and sand content but low organic matter (OM), promote low SMX adsorption and rapid transport. In contrast, the volcanic ash-derived Andisols from Frutillar (FRU), Nueva Braunau (NBR), and Osorno (OSR) have high OM and cation exchange capacity (CEC), which enhance their ability to retain SMX and reduce its mobility. Adsorption batch, kinetics, and column breakthrough curve (BTC) experiments were conducted alongside transport modelling. The adsorption kinetics of SMX in CLL soil followed a pseudo-first-order (PFO) model, while FRU, NBR, and OSR soils aligned with a pseudo-second-order (PSO) model. Freundlich isotherms effectively described SMX adsorption in CLL and OSR soils, indicating multilayer adsorption, while Langmuir isotherms fit the FRU and NBR soils, suggesting monolayer adsorption. Using HYDRUS-1D software, we simulated SMX transport in soil columns. BTCs were best modelled using a two-site sorption model with both equilibrium and kinetic adsorption. SMX was more mobile in CLL soil due to its lower organic matter (OM) content and adsorption capacity. In contrast, FRU, NBR, and OSR soils showed slower transport, reflecting higher OM content and greater adsorption capacity, reducing SMX leaching. These findings emphasize the importance of soil properties, such as OM content, in influencing SMX behavior, and are vital for assessing environmental impacts and developing mitigation strategies
Efficiency of combined techniques in pesticide residues removal from food: a systematic review
No full textThe global use of pesticides has steadily increased in recent years to enhance food production and protection and prolonge its shelf life. Nevertheless, pesticide residues and their association with various human diseases have raised concerns among the population, as the primary route of human exposure to pesticides is through food consumption. Consequently, removing pesticide residues from agricultural products and food is crucial for mitigating associated risks. Various treatments are employed to eliminate and degrade pesticide residues, with commonly used conventional techniques such as washing, peeling, and cooking being used. Additionally, emerging techniques such as ultrasound, ozone, electric current, plasma, and ultraviolet light have been applied to remove these residues. In this study, we systematically reviewed 38 articles to assess the efficacy of combined techniques for pesticide residue removal in food. The findings revealed that using combined techniques resulted in significantly higher levels of residue removal. Furthermore, combining emerging techniques with other treatments has demonstrated increased removal efficiency, significantly reducing the variability in the percentage range of residue removal. The synergistic use of ultrasound, ozone, and ultraviolet light techniques demonstrated a notably enhanced efficacy in removing pesticides, resulting in a higher elimination percentage. Among the 38 studies, 12 exhibited substantially lower variability. Moreover, ultrasound emerged as the technique with the most significant synergistic effect when combined with other techniques, enhancing the overall efficiency of pesticide residue removal. Among the 12 studies with lower variability, 9 incorporated ultrasound, 4 ozone, and 3 ultraviolet light as part of the combined treatment. However, it is essential to note that conventional techniques also achieved considerable residue removal, even with more significant variability. This information can serve as valuable guidance for managers, decision-makers, and the public in effectively selecting appropriate techniques to eliminate pesticide residues from food before consumption or sale
Influence of the Inelastic Response of Reinforced Concrete Frame Buildings on the Inelastic Displacement and Acceleration Ratios of Nonstructural Elements
No full textDamage to Nonstructural Elements (NEs) observed during recent major earthquakes indicates that the seismic design of NEs can significantly affect the overall seismic performance of buildings. NEs are subjected to floor accelerations that are usually higher than ground accelerations, resulting in an increased likelihood of inelastic deformations at their anchorages or support elements. However, the inelastic response of NEs has not been comprehensively analyzed. This research evaluates the influence of the inelastic behavior of Reinforced Concrete Frame Buildings (RCFBs) on the Inelastic Displacement Ratios (IDRs) and Inelastic Acceleration Ratios (IARs) of acceleration sensitive NEs, IDRs and IARs being important parameters to characterize the inelastic response of NEs. For this purpose, three RCFBs located in Colombia were subjected to scaled ground motions representing different levels of seismic intensity. The findings of this research are: a) as buildings enter the inelastic range, the IDRs show a reduced oscillation amplitude, and the local minima of the IDRs occur at the effective modal periods of the building rather than at the modal periods; b) existing prediction equations for IDRs provide good estimates for low seismic intensities (i.e. essentially elastic building response) and reasonable estimates for higher seismic intensities; c) the characteristic period of the IARs remains relatively insensitive to seismic intensity levels; and d) prediction equations for IARs provide accurate results regardless of seismic intensity levels, especially when the NE damping ratio is relatively low.ANI
Bird sensitivity map for wind energy development in the Magallanes and Chilean Antarctica Region
No full textTesis (Magister en Recursos Naturales)--Pontificia Universidad Católica de Chile, 2025Se ha identificado una brecha asociada con la limitada información sobre la avifauna que permita evaluar el posible impacto negativo de los futuros proyectos eólicos en la Región de Magallanes sobre las aves. En este documento, se desarrolló un análisis territorial que considera la sensibilidad del ensamble de avifauna, así como la factibilidad y el potencial eólico para el desarrollo de proyectos, integrando esta información para identificar sectores de mayor o menor “conflicto” entre intereses de desarrollo energético y medioambientales. Tras un análisis de sensibilidad de las especies de avifauna a nivel regional, se seleccionaron las 10 especies más vulnerables para construir modelos de distribución mediante máxima entropía (MaxENT), a partir de los cuales se elaboró un mapa regional de sensibilidad de avifauna. Paralelamente, se generó un mapa de factibilidad operacional basado en zonas de exclusión técnica para este tipo de proyectos y en el potencial eólico. La superposición de esta información permitió identificar áreas de conflicto entre intereses ambientales y de desarrollo eólico, clasificadas en niveles Alto (12.096 km²), Medio (45.903 km²) y Bajo (16.226 km²). Los resultados obtenidos muestran coincidencias con otros estudios relacionados tanto con análisis de sensibilidad de especies de avifauna, como con potencial eólico para el desarrollo energético, lo que permite proponer esta metodología como una herramienta parsimoniosa y actualizable, útil para la toma de decisiones territoriales, energéticas y medioambientales en la Región de Magallanes.Palabras clave: Mapa de sensibilidad de avifauna, Modelo de distribución de especies, impacto del desarrollo energético
Use of an Advanced Hybrid Closed Loop System During Marathon Running: Case Examples and Clinical Implications
No full textBackground and aims: Maintaining glucose levels in the target range during aerobic training and athletic competition is especially difficult. The use of Automated Insulin Delivery (AID) technology is increasing, but exercise continues to be a challenge for persons with type 1 diabetes (T1D). In this case report series, we present 3 cases (C1, C2 and C3) of persons with T1D who used the MiniMed 780G during marathon races. We describe the strategies they used before, during and after the race to manage their glycaemia as well as the results of these strategies on their glycaemic control during the race. Methods: The Medtronic CareLink platform was employed to remotely access insulin pump settings and glycaemic outcomes. Race parameters were obtained from sport watches. Supplemental data were obtained through interviews. Results: Carelink data for Cases 1, 2, and 3 before the race were downloaded: Time in range (TIR) 70-180 mg/dL 89%, 76%, 82%; time above range (TAR) > 180 mg/dL, 9%, 20%, 16%; time below range (TBR) < 70 mg/dL, 1%, 4%, 1%, respectively. The breakfast insulin reduction percentages were -25%, 0%, and 0% for C1, C2, and C3, respectively. In all three cases, insulin dose reduction was applied to the pre-race snack at percentages of -50%, -100% and -83%. The consumption of carbohydrates during the race was 0.39 g/kg/hour, 0.42 g/kg/hour, and 0.5 g/kg/hour, respectively. The total amount of carbohydrates consumed was 101 g, 120 g, and 115 g, respectively. Throughout the race, a temporary target was used for all cases. Conclusions: These cases provide insights for healthcare professionals who assist athletes with T1D using AID systems during prolonged physical activities. Highlighting the significance of specialised education, planning, and personalised approaches.National Institute of Child Health and Human Development of the National Institutes of Health (NIH), University of Virginia, No. 2R01HD051498-06A
Water balance in the Chilean Altiplano: exploring the spatiotemporal scales of coupled atmospheric-hydrogeological processes
No full textTesis (Doctor in Engineering Sciences)--Pontificia Universidad Católica de Chile, 2025Tesis (Doctor of Philosophy)--University of Edinburgh, 2025Esta investigación estudia los procesos multi-escala que gobiernan el balance hídrico en el Altiplano chileno, una región árida y de gran altitud compuesta por múltiples cuencas endorreicas. Mediante el uso de observaciones in situ, datos de teledetección y modelos numéricos, se analiza cómo la precipitación, la evaporación y el agua subterránea interactúan en escalas continental, regional y de cuenca. A gran escala, se muestra que ∼60% de la variabilidad intraestacional de la precipitación proviene de oscilaciones de alta frecuencia (<20 días) del Monzón de Sudamérica, desencadenadas por ondas de Rossby originadas en la Zona de Convergencia del Pacífico Sur. Estas oscilaciones provocan cambios abruptos entre fases monzónicas activas e inactivas, definiendo cuándo y dónde ocurre la precipitación. A escala regional, una circulación térmicamente impulsada genera un colapso de la capa límite atmosférica al mediodía sobre el desierto y transporta aire más frío y seco hacia humedales y lagunas adyacentes, creando peaks pronunciados de evaporación. Esta interacción pone de manifiesto cómo la dinámica de la capa límite regula la pérdida de agua a la atmósfera en un entorno heterogéneo. Por último, a nivel de cuenca, se observa que la recarga de agua subterránea ocurre en zonas de gran altitud donde la precipitación excede la evaporación. Por el contrario, el agua subterránea aflora en humedales, lagunas y zonas ribereñas de baja altitud que actúan como vías preferenciales para la evaporación, siendo los principales puntos de descarga del sistema endorreico. En conjunto, se demuestra que la precipitación establece el marco de la disponibilidad de agua, los procesos en la capa límite atmosférica rigen las tasas de evaporación y el agua subterránea media los flujos a escala de cuenca. Reconocer estos acoplamientos multiescala es esencial para estimar con precisión el balance hídrico y elaborar estrategias de gestión sostenible ante la variabilidad climática y la creciente demanda de recursos hídricos.ANIDFONDECY
Parental Math Beliefs and Home Math Experiences of Preschoolers in Chile: A Qualitative Study
No full textThe home math environment is a context where children develop early mathematics skills, which are key for their future learning. Most of the research in the field, however, comes from North American and European countries and is largely based on self-report questionnaires. This qualitative study describes the beliefs, attitudes and experiences of parents of preschoolers in Chile. Twenty-three parents (21 mothers) of 3–4-year-old children attending public preschools were interviewed. Their responses were transcribed verbatim and analysed using a reflexive thematic analysis approach. The findings revealed four themes in parent interviews: parents' attitudes and beliefs towards mathematics, parents' participation in children's learning, home learning strategies, and parents' expectations. The results of this study provide a better understanding of parental math beliefs and the math experiences parents engage in with their children at home, with implications for parents to support their children's math development.ANI
BASS. XLV. Quantifying Active Galactic Nuclei Selection Effects in the Chandra COSMOS-legacy Survey with BASS
No full textDeep extragalactic X-ray surveys, such as the Chandra COSMOS-Legacy field (CCLS), are prone to be biased against active galactic nuclei (AGN) with high column densities due to their lower count rates at a given luminosity. To quantify this selection effect, we forward model nearby (z similar to 0.05) AGN from the BAT AGN Spectroscopic Survey (BASS) with well-characterized (greater than or similar to 1000 cts) broadband X-ray spectra (0.5-195 keV) to simulate the CCLS absorption distribution. We utilize the BASS low-redshift analogs with similar luminosities to the CCLS (L-2-10keV(int) similar to 10(42-45) erg s), which are much less affected by obscuration and low-count statistics, as the seed for our simulations and follow the spectral fitting of the CCLS. Our simulations reveal that Chandra would fail to detect the majority (53.3%; 563/1056) of obscured (N-H >= 10(22) cm(-2)) simulated BASS AGN given the observed redshift and luminosity distribution of the CCLS. Even for detected sources with sufficient counts (>= 30) for spectral modeling, the level of obscuration is significantly overestimated. This bias is most extreme for objects whose best fit indicates a high-column density AGN (N-H >= 10(24) cm(-2)), since the majority (66.7%; 18/27) of these are actually unobscured sources (N-H < 10(22) cm(-2)). This implies that previous studies may have significantly overestimated the increase in the obscured fraction with redshift and the fraction of luminous obscured AGN. Our findings highlight the importance of directly considering obscuration biases and forward modeling in X-ray surveys, as well as the need for higher-sensitivity X-ray missions such as the Advanced X-ray Imaging Satellite (AXIS), and the importance of multiwavelength indicators to estimate obscuration in distant supermassive black holes