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Accessibility and ageing neighbourhoods: a cluster-based taxonomy to promote ageing in place
No full textAgeing in place is an established policy option to adapt existing urban settings to the needs of an increasingly older and rapidly ageing population. The possibility to access facilities and services is fundamental in this sense, but accessibility to relevant urban opportunities changes according to the places taken into account, affecting a neighbourhood potential for promoting ageing in place. In this paper, we aim to identify typologies of ageing neighbourhoods according to the access they provide to significant places and services. We propose a taxonomy based on (1) the concentration of older people, (2) their socioeconomic standing, (3) the amount of opportunities available within walking distance, and (4) the possibility of reaching public transport as a precondition to access valued opportunities in other areas of a city. Our analysis focuses on Santiago de Chile, a metropolis representative of other unequal, rapidly ageing Global South urban settings. We identify ageing neighbourhoods using hierarchical cluster analysis, and we define six categories according to the access they provide to relevant urban opportunities. Such accessibility-based taxonomy of ageing neighbourhoods can be relevant for promoting ageing in place cities, identifying what planning and policy actions are better suited to enhance accessibility to urban opportunities.ANID/Fondecyt No. 11220220ANID/Fondecyt No. 1250406ANID/Fondap No. 1523A000
Validation of the Reflux Symptom Index in French-Speaking Quebec Patients
No full textImportance. There is a need to culturally adapt this commonly used patient-reported outcome measure, the Reflux SymptomIndex (RSI), for use in Canada and Quebec’s French population.Objective. To translate and validate the RSI for use in Quebec French speakers, ensuring reliability and validity within thispopulation. Design. Prospective case-control study. Setting. Voice and Dysphagia Laboratory at the McGill University Health Centre in Montreal, Quebec, Canada. Participants. Patients with laryngopharyngeal reflux (LPR) and healthy controls were recruited during outpatient clinical laryngology visits. Participants were eligible if they were at least 18 years old and spoke French as their native language. Intervention or Exposures. A Quebec-French version of the RSI (Q-Fr-RSI) was validated using the “translation-back-translation” method. Participants completed the Q-Fr-RSI, Fr-VHI, and their laryngoscopy was examined and assigned a Reflux Finding Score at their initial visit. Participants repeated the Q-Fr-RSI via telephone follow-up. Main Outcome Measures. Feasibility, internal consistency, test-retest reliability, and construct validity of the Q-Fr-RSI were assessed. Results. Eighty-nine participants were recruited: 49 patients within the experimental group and 40 subjects within the control group. The feasibility was evaluated as percentage of missing answers in the full sample at the first time point, 0%, and second time point, 1.2%. Internal consistency via Cronbach’s alpha was high (.90). Intra-rater reliability via intraclass correlation demonstrated good level of agreement (.84). Internal validity demonstrated a strongly significant difference between the groups’ answers (mean score of 23.9 vs 6.65, respectively, P < .001).Conclusions. This data suggest that the Q-Fr-RSI can be used to assess LPR in the French-speaking Canadian population. Relevance. In the bilingual country of Canada, and especially in the province of Quebec where over 90% of people speak French, an appropriate validation of the Q-Fr-RSI allows all patients to be monitored adequately. A Quebec-French patient-reported outcome measure can accurately represent these patients in future research studies utilizing these metrics
Stellar atmospheric parameters and chemical abundances of ∼5 million stars from S-PLUS multiband photometry
No full textContext. The APOGEE, GALAH, and LAMOST spectroscopic surveys have substantially contributed to our understanding of the Milky Way by providing a wide range of stellar parameters and chemical abundances. Complementing these efforts, photometric surveys that include narrowband and medium-band filters, such as Southern Photometric Local Universe Survey (S-PLUS), provide a unique opportunity to estimate the atmospheric parameters and elemental abundances for a much larger number of sources, compared to spectroscopic surveys., Aims. Our aim is to establish methodologies for extracting stellar atmospheric parameters and selected chemical abundances from S-PLUS photometric data, which cover approximately 3000 square degrees, by applying seven narrowband and five broadband filters., Methods. We used all 66 S-PLUS colors to estimate parameters based on three different training samples from the LAMOST, APOGEE, and GALAH surveys, applying cost-sensitive neural network (NN) and random forest (RF) algorithms. We kept the stellar abundances that lacked corresponding absorption features in the S-PLUS filters to test for spurious correlations in our method. Furthermore, we evaluated the effectiveness of the NN and RF algorithms by using estimated T-eff and log g values as the input features to determine other stellar parameters and abundances. The NN approach consistently outperforms the RF technique on all parameters tested. Moreover, incorporating T-eff and log g leads to an improvement in the estimation accuracy by approximately 3%. We kept only parameters with a goodness-of-fit higher than 50%., Results. Our methodology allowed us to obtain reliable estimates for fundamental stellar parameters (T-eff, log g, and [Fe/H]) and elemental abundance ratios such as [alpha/Fe], [Al/Fe], [C/Fe], [Li/Fe], and [Mg/Fe] for approximately five million stars across the Milky Way, with a goodness-of-fit above 60%. We also obtained additional abundance ratios, including [Cu/Fe], [O/Fe], and [Si/Fe]. However, these ratios should be used cautiously due to their low accuracy or lack of a clear relationship with the S-PLUS filters. Validation of our estimations and methods was performed using star clusters, Transiting Exoplanet Survey Satellite (TESS) data and Javalambre Photometric Local Universe Survey (J-PLUS) photometry, further demonstrating the robustness and accuracy of our approach., Conclusions. By leveraging S-PLUS photometric data and advanced machine learning techniques, we have established a robust framework for extracting fundamental stellar parameters and chemical abundances from medium-band and narrowband photometric observations. This approach offers a cost-effective alternative to high-resolution spectroscopy. The estimated parameters hold significant potential for future studies, particularly when classifying objects within our Milky Way or gaining insights into its various stellar populations
Online combinatorial assignment in independence systems
No full textWe consider an online multi-weighted generalization of several classic online optimization problems called the online combinatorial assignment problem. We are given an independence system over a ground set of elements and agents that arrive online one by one. Upon arrival, each agent reveals a weight function over the elements of the ground set. If the independence system is given by the matchings of a hypergraph, we recover the combinatorial auction problem, where every node represents an item to be sold, and every edge represents a bundle of items. For combinatorial auctions, Kesselheim et al. showed upper bounds of O (log log (k)/log (k) and O (log log (n)/log (n) on the competitiveness of any online algorithm, even in the random order model, where k is the maximum bundle size and n is the number of items. We provide an exponential improvement by giving upper bounds of O (log (k)/k, and O (log (n) for the prophet IID setting. Furthermore, using linear programming, we provide new and improved guarantees for the k-bounded online combinatorial auction problem (i.e., bundles of size at most k). We show a
-competitive algorithm in the prophet IID model, a -competitive algorithm in the prophet-secretary model using a single sample per agent, and a -competitive algorithm in the secretary model. Our algorithms run in polynomial time and work in more general independence systems where the offline combinatorial assignment problem admits the existence of a polynomial-time randomized algorithm that we call certificate sampler. These systems include some classes of matroids, matroid intersections, and matchoids
Modern Handball: A Dynamic System, Orderly Chaotic
No full textBackground: Handball is conceptualized as a complex dynamic system characterized by emergent behaviors, non-linearity, attractors, and self-organization, influenced by players’ interactions, environmental conditions, and tactical elements. This perspective emphasizes the importance of communication, adaptive strategies, and modern teaching methods like Non-linear Pedagogy for improving technical-tactical behaviors, advocating for a multidisciplinary approach to deepen its understanding. Thus, this narrative review aims to explore how modern theories and approaches can be integrated to provide a deeper understanding of handball’s complexity from a broad and multidisciplinary perspective. (2) Methods: A narrative review approach was employed to integrate key concepts such as chaos theory, self-organization, and non-linear pedagogy as they apply to the game’s technical-tactical dynamics. The methodology involved a comprehensive literature review to identify how emergent perceptual and social interactions influence collective performance. (3) Results: Findings indicate that team performance is not solely dependent on individual skills but on their capacity for synchronization, adaptation, and self-organization in response to competitive demands. Communication and internal cohesion emerged as critical factors for adjustment and autonomous decision-making, framed within Luhmann’s social systems theory. (4) Conclusions: The conclusions suggest that training methodologies should incorporate non-linear approaches that promote self-organization, adaptability, and player autonomy. This multidisciplinary perspective offers a deeper understanding of handball and highlights its applicability to other team sports, maximizing performance through an integrative analysis of social, philosophical, and communicative components.ANIDANID FONDECYTFONDAPFONDA
When Latin American Melodrama Meets Nordic Noir: How SVOD Reshapes Chilean TV Fiction
No full textThis article aims to understand the impact of subscription video-on-demand commissions on locally produced content in Latin America’s smaller markets. It focuses on the case of 42 Days of Darkness (2022), the first Netflix Original in Chile produced without the participation of local broadcast channels nor with contributions from state funds. Through a contextualized textual analysis of the series, focusing on Netflix’s strategic approach to national/global production, a shift has been identified in both the look and practice of national TV series programming with this new stakeholder. Although the local industry has already ventured into the detective genre based on local crimes, Netflix’s first production in Chile adopted narratives and visual motifs congruent with melancholic elements of Nordic noir. We conclude that one of Netflix’s main strategies in this project was to embrace the global popularity of the Scandinavian genre’s aesthetics while maintaining elements of Latin American melodrama, a predominant genre in the region, in order to appeal to local audiences, creating content with a negotiated, “glocal” appeal. The participation of subscription video-on-demand giants in small industries such as Chile could help to create captivating TV series and energize the local audiovisual production industry. However, it might lead to the homogenization of content and the erasure of cultural specificit
Prediction of phase equilibrium in polyphenolic systems using PC-SAFT
No full textTesis (Doctor in Engineering Sciences)--Pontificia Universidad Católica de Chile, 2025Los polifenoles, una familia diversa de metabolitos secundarios presentes en matrices vegetales, son altamente valorados por sus beneficios para la salud. Sin embargo, su extracción y purificación presentan desafíos significativos, ya que son escasos en su forma pura y generalmente requieren el uso de solventes tóxicos e inflamables que dejan residuos no deseados en el producto final. El diseño sostenible de los procesos de extracción requiere no solo solventes amigables con el medio ambiente, sino también conocer la solubilidad de los polifenoles. Debido al alto costo de los polifenoles y la dificultad para obtenerlos, los datos experimentales sobre su solubilidad son limitados o inexistentes, lo que hace necesario contar con modelos predictivos robustos para describir un comportamiento en diversos solventes. Este trabajo se centra en predecir el equilibrio sólido-líquido (SLE) de los dímeros de procianidinas, compuestos polifenólicos derivados de los monómeros (-)-epicatequina y (+)-catequina, en solventes como agua, solventes eutécticos profundos (DES, por sus siglas en inglés) y sus mezclas. El estudio utiliza la ecuación de estado PC-SAFT (Perturbed Chain Statistical Associating Fluid Theory), calibrada con datos experimentales de SLE para (-)-epicatequina y (+)-catequina. A pesar del objetivo inicial de estudiar ambos monómeros y sus derivados, el análisis se limitó a las procianidinas compuestas exclusivamente por (-)-epicatequina. Esta limitación surgió debido a las incertidumbres estructurales de la (+)-catequina al estar en contacto con agua, como lo confirmó el análisis PXRD y las correlaciones entre su solubilidad y la razón entre masa de soluto y solvente. El estudio se dividió en tres etapas principales. En primer lugar, se intentó desarrollar herramientas computacionales en Python para implementar las ecuaciones de PC-SAFT y permitir la estimación de parámetros a partir de datos experimentales. Estas herramientas, construidas con NumPy, SciPy y Pyomo, no incluyeron el término asociativo de PC-SAFT, necesario para modelar polifenoles, debido a su complejidad. Por lo tanto, se usaron herramientas computacionales externas junto con rutinas escritas en este trabajo que permiten modelar SLE y calcular solubilidades y coeficientes osmóticos. La plataforma computacional incluye rutinas de optimización de parámetros que utilizan los algoritmos Nelder-Mead y de evolución diferencial para ajustar los datos experimentales. La segunda etapa involucró la medición experimental y modelación termodinámica de la solubilidad de la (-)-epicatequina en cinco sistemas acuosos, incluidos agua y DES, a 293.15, 303.15 y 313.15 K bajo presión atmosférica. La solubilidad se midió mediante métodos espectrofotométricos y gravimétricos, y el análisis PXRD confirmó la estabilidad de la estructura cristalina durante la experimentación. Los resultados mostraron que la solubilidad de la (-)-epicatequina varió significativamente entre los solventes, pero se mantuvo relativamente constante con la temperatura. Las mayores solubilidades se observaron en sistemas DES que contenían cloruro de colina y 25 % en peso de agua, con DES1+agua alcanzando una solubilidad más de 40 veces mayor que en agua. Estos hallazgos resaltan la importancia del contenido de agua en las formulaciones DES, equilibrando los aumentos de solubilidad y los problemas de viscosidad. Para la modelación, los parámetros PC-SAFT de (-)-epicatequina se ajustaron a datos experimentales de densidad y solubilidad, permitiendo predecir su comportamiento en diversos solventes. Los parámetros de interacción binaria se ajustaron para cada solvente, y el rendimiento del modelo se evaluó utilizando la métrica AARD, logrando desviaciones inferiores al 10% en la mayoría de los sistemas. Las predicciones reforzaron la idoneidad del 25 % en peso de agua como contenido óptimo para los DES, donde el aumento de la solubilidad debido a la adición de loruro de colina alcanza su punto máximo mientras se mantiene una viscosidad razonable. En la etapa final, se predijo la solubilidad de las procianidinas utilizando el enfoque wJPM, que estima parámetros oligoméricos a partir de parámetros monoméricos. Se predijo que las procianidinas compuestas por (-)-epicatequina tienen una mayor solubilidad que su monómero debido a sitios de asociación adicionales. Las procianidinas de tipo A exhibieron mayor solubilidad que las de tipo B, debido a la asimetría de sus esquemas de asociación. Aunque en el caso de la procianidina B2 en agua hay discrepancia con un experimento, las predicciones de PC-SAFT son lógicas y cualitativamente correctas. Este estudio avanza en la comprensión de la solubilidad de los polifenoles en sistemas complejos de solventes, apoyando la transición hacia solventes ecológicos para procesos de extracción sostenibles. Demuestra la utilidad de PC-SAFT como herramienta predictiva para modelar solubilidades y su potencial para guiar el diseño de procesos para productos naturales de alto valor. Al vincular parámetros oligoméricos con los monoméricos, este trabajo ofrece un marco para extender las predicciones de solubilidad a sistemas moleculares más complejos, contribuyendo al desarrollo de tecnologías verdes y eficientes.ANIDFONDECY
Presentación del Dossier Resistencias al reformismo borbónico: pueblos de indios, milicias religiosas y corporaciones
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Influence of Monstera riedrichsthalii bionic textures on the tribological and vibration behavior of rolling bearings
No full textSurface texturing has been proven to be an effective method for improving the lubrication characteristics and tribological behavior of tribo-pairs under various operating conditions. Inspired by the unique Swiss cheese-like leaves of Monstera riedrichsthalii, eight bionic texture patterns were introduced. The influence of vein features, such as costal vein angles (45° and 60°), vein symmetry (symmetric, asymmetric), and elliptical holes, on the tribological and vibration characteristics of rolling bearings was investigated under starved lubrication through a wear test rig and time‒frequency domain vibration signal analysis. The results show that the average coefficients of friction and wear losses of the Monstera riedrichsthalii bionictextured groups are generally lower than those of the smooth reference. The amplitudes and parameters (i.e., peak value, root mean square (RMS), and crest factor) of the time-domain vibration signals of the textured groups are greater than those of the smooth group in the early stages, but the vibration parameters of most textured groups are lower than those of the smooth bearings in the later stages, especially those of the groups with elliptical holes. The amplitudes and power spectral density (PSD) curves of the frequency-domain vibration signals exhibit similar variations to those of the time-domain signals. Compared with the smooth reference, the Monstera riedrichsthalii bionictextured group with a combination of 45° secondary-vein angle, asymmetry, and elliptic holes can provide excellent tribological and vibration performance. Its well-lubricating period, average coefficient of friction (CoF), and mass loss can be effectively prolonged or reduced by 37.4%, 7.3%, and 43.9%, respectively