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Effects of Regional Stress State and Pore Fluid Pressure on the Onset and Style of Caldera Collapse
No full textCollapse calderas result from subsidence of a magma reservoir roof during large-volume eruptions. Whilst calderas form in various tectonic settings, it is unclear how regional (“far-field”) forces influence caldera fault nucleation, orientation and architecture. Furthermore, although the presence of a pore fluid is known to reduce the effective stress, it is typically neglected in past caldera collapse models. Utilizing two-dimensional Distinct Element Method (DEM) models, we explore the influences of regional stress and pore fluid pressure on the evolutions of stress, strain and faulting during caldera subsidence. We simulate a shallow magma volume as an inviscid inclusion within a homogeneous crust and decrease the inclusion's pressure to model magma withdrawal. Results reveal that the critical underpressure needed to trigger collapse is reduced in extensional regimes, particularly in fluid-saturated conditions, due to lowered frictional resistance on faults. We observe three progressive deformation stages: initial fracturing at the reservoir roof, collapse onset, and complete roof failure. The geometry of faults depends on the tectonic setting, with extensional conditions favoring steeper fault dips and compressional settings promoting shallower, outward-dipping reverse faults. Models simulating a fluid-saturated crust exhibit similar effects to those models that simulate lower strength materials. This study highlights the need to account for regional stress states and crustal properties in volcanic hazard assessment, especially in caldera systems with complex hydrothermal or tectonic influences. Our findings are compared with recent collapse episodes, underscoring the utility of DEM modeling in understanding crustal responses to magma depletion
Physicochemical characterization, bioactive compounds, and antioxidant activity of the wild berry Ribes magellanicum
No full textThe Patagonian wild berry Ribes magellanicum has promising applications in food and nutrition due to its flavor and the presence of health-promoting bioactive compounds. Relevant chemical, physicochemical, and structural characteristics of the fruit for its utilization as food were investigated. The average moisture content was 79.3% while protein, lipids, sugars, and crude fiber amounted to 7.4, 5.8, 64.3, and 14.5 g/100 g dry fruit, respectively. Average values of fruit diameter, number of seeds, juice yield, soluble solids, and pH were determined as 5 mm, 17, 59.2%, 15.5 °Brix, and 4.3, respectively. Total phenolic compounds amounted to 2543 mg/100 g dry weight, anthocyanins to 561 mg C3G/100 g dry weight, and carotenoids to 43.3 mg/100 g oil. ORAC and DPPH values were 36.0 and 15.8 mmol TE/100 g dry weight, respectively. Linoleic acid predominated in a lipid profile that exhibited a good ω-6/ω-3 ratio (1.37). The structure of the berry consisted of a skin (exocarp) and a pulp (mesocarp) that contained many seeds representing 54% of the weight of the berry. These characteristics of R. magellanicum are similar to other wild Patagonian berries that have found applications as foods due to their convenience and the presence of abundant bioactive compounds
Pharmacotherapy and non-invasive neuromodulation for neuropathic pain: a systematic review and meta-analysis.
No full textThere remains a substantial unmet need for effective and safe treatments for neuropathic pain. The Neuropathic Pain Special Interest Group aimed to update treatment recommendations, published in 2015, on the basis of new evidence from randomised controlled trials, emerging neuromodulation techniques, and advances in evidence synthesis
3D-QSAR Design of New Bcr-Abl Inhibitors Based on Purine Scaffold and Cytotoxicity Studies on CML Cell Lines Sensitive and Resistant to Imatinib
No full textBcr-Abl inhibitors such as imatinib have been used to treat chronic myeloid leukemia (CML). However, the efficacy of these drugs has diminished due to mutations in the kinase domain, notably the T315I mutation. Therefore, in this study, new purine derivatives were designed as Bcr-Abl inhibitors based on 3D-QSAR studies. Methods: A database of 58 purines that inhibit Bcr-Abl was used to construct 3D-QSAR models. Using chemical information from these models, a small group of new purines was designed, synthesized, and evaluated in Bcr-Abl. Viability assays were conducted on imatinib-sensitive CML cells (K562 and KCL22) and imatinib-resistant cells (KCL22-B8). In silico analyses were performed to confirm the results. Results: Seven purines were easily synthesized (7a–g). Compounds 7a and 7c demonstrated the highest inhibition activity on Bcr-Abl (IC50 = 0.13 and 0.19 μM), surpassing the potency of imatinib (IC50 = 0.33 μM). 7c exhibited the highest potency, with GI50 = 0.30 μM on K562 cells and 1.54 μM on KCL22 cells. The GI50 values obtained for non-neoplastic HEK293T cells indicated that 7c was less toxic than imatinib. Interestingly, KCL22-B8 cells (expressing Bcr-AblT315I) showed greater sensitivity to 7e and 7f than to imatinib (GI50 = 13.80 and 15.43 vs. >20 μM, respectively). In silico analyses, including docking and molecular dynamics studies of Bcr-AblT315I, were conducted to elucidate the enhanced potency of 7e and 7f. Thus, this study provides in silico models to identify novel inhibitors that target a kinase of significance in CML
Power Shift: Decarbonization and the New Dynamics of Energy Markets
No full text© 2025 by the author.This paper examines the transformative effects of decarbonization on electricity market design, emphasizing the challenges and opportunities posed by the rapid integration of renewable energy sources such as wind and solar. It analyzes the evolution of key wholesale market segments—including day-ahead, real-time, capacity, long-term purchase agreements, ancillary services, and transmission markets—highlighting their critical roles in managing the variability of renewable energy generation through efficient price signals and resource coordination. Variable renewable energy integration introduces significant operational challenges, including overgeneration risks, ramping capacity demands, forecast inaccuracies, and transmission constraints. Addressing these issues requires enhanced market flexibility, dynamic pricing mechanisms, and advanced real-time balancing strategies. This paper assesses these challenges, offering strategies to align generation with demand and optimize market outcomes. As electricity systems evolve, legacy market structures must adapt to incorporate carbon-free resources while maintaining grid reliability and economic sustainability. By exploring case studies such as Chile and California, this paper demonstrates the importance of targeted innovations in market design, regulatory frameworks, and operational technologies. It advocates for a holistic approach to ensure a reliable, affordable, and equitable transition to a decarbonized energy future.Chilean National Agency for Research and DevelopmentChilean National Agency for Research and Developmen
Children’s right to play in Chilean hospitals: A forgotten right?—A qualitative study protocol
No full textBackground Despite being a recognised human right (art. 31 of the United Nations Convention on the Rights of the Child), children’s right to play is still insufficiently researched, understood and, above all, implemented. In Chile, the National Child Health Programme recognises the importance of this right for the hospitalised children but makes its provision dependent on the hospital’s capacity. We therefore hypothesise that the provision of children’s right to play in Chilean hospital settings will be irregular, varying from institution to institution, possibly reflecting the existing socio-economic inequalities in the country, thereby leaving much room for improvement. Aims This study aims to collect qualitative data on the institutional arrangements and opportunities for children’s play in public hospitals in Chile. Specifically, our goal is to (a) interpret the conditions and opportunities for play that Chilean public hospitals provide to children and adolescents; (b) interpret institutional arrangements and professional experiences of children’s play in those institutions; (c) identify factors that favour and/or limit opportunities for children’s play in the Chilean hospital setting. Methods This is exploratory qualitative research, combining multiple and instrumental case study with ethnographic research. Its data collection techniques are semi-structured interviews with professionals in hospital settings (supported by a self-assessment questionnaire), and non-participant observations of hospital playrooms (and/or other play spaces). Conclusion This will be the first study to investigate children’s right to play in Chilean hospitals, with a particular focus on the extent of its implementation, its understanding among health professionals, as well as existing limitations and opportunities for its development
ggsoiltexture: An R package based on ggplot2 for soil texture data visualization
No full textThe soil science community is increasingly adopting R for reproducible data analysis and visualization. Soil texture data visualized in ternary plots is a key component in soil physics, and challenging to plot in a clear way while maintaining consistent data visualization components. reproducible functions in R can lead to clearer and reproducible methods for plotting it. Embracing these principles, the authors developed ggsoiltexture, an R package leveraging the ggplot2 framework to create customizable and publication-quality soil texture plots. The package demonstrated accurate and visually appealing representations of soil texture classifications through case studies using already-published data
Topografía y Material Vegetal como Componentes Arquitectónicos. Diseño de un Sistema de Enfriamiento y Cortafuego en el Jardín Botánico Nacional, Viña del Mar
No full textTesis (Arquitecto y Magíster en Arquitectura)--Pontificia Universidad Católica de Chile, 2025En un contexto marcado por el aumento de las temperaturas y de los incendios forestales por la acción humana, esta investigación se centra en el desarrollo de una solución arquitectónica que integre topografía y material vegetal como herramientas esenciales para enfrentar estas problemáticas.El proyecto, situado en el Jardín Botánico Nacional de Viña del Mar (JBN), aborda dos desafíos principales: reducir las temperaturas del entorno mediante sistemas de enfriamiento pasivo y crear una barrera que actúe como cortafuego, respondiendo a la creciente probabilidad de ocurrencia de incendios que han afectado el área en los últimos años, siendo el más devastador el de 2024.Más allá de resolver problemáticas específicas del Jardín Botánico Nacional, el proyecto pretende sentar precedentes en el diseño arquitectónico que combinen mitigación climática y estrategias de protección contra incendios, ofreciendo un modelo replicable en contextos similares
High spatial resolution WRF-Chem modeling in Quito, Ecuador
No full textThe WRF-Chem model was applied for gas and aerosol chemistry in Quito, Ecuador, at a high horizontal resolution of 2 km. WRF-Chem was chosen due to its full coupling of meteorological and chemical processes, which is particularly suitable for complex topography and urban-scale simulations. Emission inventories were taken from EDGAR for the outer domains (32 and 8 km horizontal resolution), and local emission estimates were used for the innermost domain (2 km resolution) as initial estimates. The base year of simulation was 2018, and two months were chosen: April and December. WRF-Chem results were tested at five air quality stations across the Quito metropolitan area. To reduce bias between modeled and observed concentrations, Quito 2011 baseline emissions for CO, NOx, SO2, and PM2.5 were adjusted by factors of 1.5, 0.75, 0.30 and 3.0 approximately, resulting in annual emission estimates of 300, 27, 1.5 and 7.5 kilotonnes per year (kton per year) for CO, NOx (expressed as NO2 equivalent), SO2 and PM2.5, respectively. The model run with these adjusted emissions showed good performance for CO, NOx, SO2, and O3 (r ∼0.4–0.8), but performance was lower for PM2.5 (r ∼0.4–0.5), particularly in the afternoon. This is ascribed mainly to an underestimation of secondary organic aerosol formation. The impact of biogenic VOC emissions on ozone and PM2.5 is positive but small (+3–8%), and the inclusion of aerosol radiative feedback is minor (∼−0.5%), because of the relatively small ambient PM2.5 concentrations in Quito
Defensoría Local de las Personas Mayores de la I. Municipalidad de San Ramón
No full textTesis (Magíster en Políticas Públicas)--Pontificia Universidad Católica de Chile, 2024Propuesta de creación de una Defensoría Local de las Personas Mayores en San Ramón, basada en un diagnóstico cualitativo y estadístico sobre violencia y vulneración de derechos. Incluye análisis normativo, entrevistas a actores clave y diseño de un modelo de atención integral con enfoque psicosociojurídico, orientado a mejorar el acceso a la justicia y la protección local de este grupo prioritario