Artículos Ingeniería

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From Efficiency to Safety: A Simulation-Based Framework for Evaluating Empty-Container Terminal Layouts
(2026) Vera-Carrasco, Cristóbal; Palma, Cristian D.; Muñoz-Herrera, Sebastián
Empty container depot (ECD) design significantly impacts maritime terminal efficiency, yet traditional evaluation approaches assess limited operational factors, constraining comprehensive performance optimization. This study develops an integrated discrete event simulation (DES) framework that simultaneously evaluates lifting equipment utilization, truck turnaround times, and potential collisions to support terminal decision-making. This study combines operational efficiency metrics with safety analytics for non-automated ECDs using Top Lifters and Reach Stackers. Additionally, a regression analysis examines efficiency metrics’ effect on safety risk. A case study at a Chilean multipurpose terminal reveals performance trade-offs between indicators under different operational scenarios, identifying substantial efficiency disparities between dry and refrigerated container operations. An analysis of four distinct collision zones with varying historical risk profiles showed the gate area had the highest potential collisions and a strong regression correlation with efficiency metrics. Similar models showed a poor fit in other conflict zones, evidencing the necessity for dedicated safety indicators complementing traditional measures. This integrated approach quantifies interdependencies between safety and efficiency metrics, helping terminal managers optimize layouts, expose traditional metric limitations, and reduce safety risks in space-constrained maritime terminals.
Study of the Deformation by Compression of a Premolar with and Without Ceramic Restoration Using Speckle Optical Interferometry
(2025) Baradit, Erik; Gutiérrez, Jorge; Yáñez, Miguel; Sumonte, Claudio; Aguilera, Cristhian
This work aimed to quantify axial deformations of a human premolar during occlusion with its antagonist and to compare them with the same premolar restored with a ceramic crown. The deformations were put under stress using a mechanical press with a force ranging from 1 to 100 Newtons. These deformations were quantified using the optical interferometry technique with a laser source (633 nm, 0.95 mW). Using a CMOS camera, interference fringes were obtained, stored, and subsequently processed. The premolars were restored with Cerasmart GC ceramic, using the CAD-CAM system. The average deformations of healthy premolars were found to be in a range of 0.69 to 1.74 µm, while the restored ones were deformed in a range of 0.53 to 1.10 µm. The results of this work showed that the Cerasmart ceramic material had similar properties to those of the natural tooth for small forces. However, for higher forces, the ceramics increased the coronal stiffness of the tooth. This modified the optimal combination of stiffness, strength, and resilience between the enamel and dentin, causing a decrease in the tooth’s ability to dissipate energy; therefore, the tooth could receive more stress. The observed mechanical properties lead to the conclusion that the Cerasmart material can be indicated for the restoration of anterior and premolar teeth in most cases where a fixed prosthesis is required.
A generalized bernoulli differential equation
(2025) Carmenate, Hector; Bosch, Paul; Nápoles, Juan; Sigarreta, José
In this paper we study a generalized form of the Bernoulli Differential Equation, employing a generalized conformable derivative. Initially, we establish a generalized variant of Gronwall’s inequality, essential for assessing the stability of generalized differential equation systems, and offer insights into the qualitative behavior of the trivial solution of the proposed equation. Subsequently, we present and prove the main results concerning the solution of the generalized Bernoulli Differential Equation, complemented by illustrative examples that underscore the advantages of this generalized derivative approach. Furthermore, we introduce a finite difference method as an alternative technique to approximate the solution of the generalized Bernoulli equation and demonstrate its validity through practical examples.
Investigating the dispersion and transport of carbon monoxide in West Africa with a focus on biomass burning and gas flaring sources
(2025) Onojeghuo, Ajoke; Fleming, Zoë; Panagi, Marios; Balzter, Heiko; Monks, Paul S.
This study presents an in-depth analysis of the dispersion and transport of carbon monoxide (CO) in West Africa, with a specific focus on the contributions from biomass burning and gas flaring activities. Utilizing data from the Global Fire Emissions Database (GFED4s) for biomass burning and the Infrared Atmospheric Sounding Interferometer (IASI) for CO concentrations, the research examines the seasonality of air pollution. Multi-seasonal 5-day trajectories of the NAME atmospheric dispersion model were employed to trace seasonal CO sources and their movement patterns. The findings highlight the dual impact of biomass burning inland and gas flaring offshore, particularly in Angola, on CO levels. Notably, the dispersion modelling process showed that emissions from gas flaring activities affect CO concentrations along the West African coast, especially during periods of lower wind speeds and dispersion rates. The study underscores the necessity of incorporating gas flaring emissions into atmospheric models to accurately simulate air pollution in the region. This comprehensive approach enhances the understanding of CO distribution and its environmental impacts, emphasizing the critical need for improved emission inventories and modeling techniques to address air pollution in West Africa.
A new generation of Early Career Researchers in atmospheric chemistry: Navigating a globalized scientific landscape
(2025) Desservettaz, Maximilien; Ramacher, Martin; Thirstrup, Simone; Barbosa, Cybelli; Diez, Sebastian; Bryant, Hannah; Hamilton, Tamryn; Schneider, Stephanie; Vohra, Karn; Li, Yuanzhe; Mishra, Sachin; Abdul, Nor; Uz Zaman, Shahid; Brown, Flossie; John, Shyno; Tiwari, Pravash; Apondo, William; Matthews, Emily
As the International Global Atmospheric Chemistry (IGAC) project marks its 35th anniversary,this paper examines the multifaceted experiences of Early Career Researchers (ECRs) navigating the increasingly globalized landscape of atmospheric chemistry. Drawing upon collective insights from the ECR Scientific Steering Committee and quantitative data from a survey of 180 ECRs across 40 countries, we investigate their primary motivations, challenges, and opportunities. Key obstacles identified include systemic difficulties in securing funding and resources, achieving sustainable work–life balance, and uncertainty around long-term career prospects, often compounded by precarious employment conditions. While globalization offers significant avenues for international collaboration, data sharing, and knowledge exchange, it concurrently presents challenges such as heightened competition, visa restrictions, regional disparities, and the risk of inequitable research practices. Despite these hurdles, ECRs are driven by a strong interest in their field, a desire to make a tangible impact on societal concerns, and the appeal of a supportive community. This perspective paper offers actionable insights focused on 4 key pillars: (i) strengthening mentoring programs; (ii) reforming funding mechanisms for improved accessibility and equity; (iii) providing targeted skill development workshops; and (iv) promoting equitable collaborations and advancing the decolonization of research practices. To foster a supportive, inclusive, and sustainable environment for the next generation of atmospheric scientists, this work underscores the urgent need for systemic change and sustained collaborative action by networks such as IGAC, as well as by senior researchers, academic institutions, and funding agencies.
Assessment of aerosol remote sensing uncertainty in urban centers of Latin America
(2025) Urquiza, Josefina; Diez, Sebastian; Tames, María Florencia; Puliafito, Salvador
La profundidad óptica de aerosoles (AOD) derivada de satélites es un indicador clave para ampliar la cobertura espacial en estudios de calidad del aire, particularmente para estimar concentraciones de PM2.5. Sin embargo, la validación de productos AOD de alta resolución sigue siendo limitada en entornos urbanos de América Latina, que se caracterizan por una dinámica compleja de aerosoles y una escasa cobertura de monitoreo terrestre. En este estudio, evaluamos el desempeño del producto MAIAC C6.1 AOD en seis ciudades latinoamericanas densamente pobladas (São Paulo, Santiago, Buenos Aires, Medellín, La Paz y Ciudad de México) entre 2015 y 2022, utilizando como referencia la red AERONET. El desempeño de MAIAC C6.1 también se comparó con su versión anterior (C6.0) y con MODIS DT, para analizar diferencias en la resolución espacial y evaluar mejoras en el rendimiento. Se observó una falta de datos AOD a nivel de superficie, especialmente en Medellín y São Paulo, junto con niveles promedio bajos (AOD < 0.2) en La Paz y Buenos Aires. El rendimiento de MAIAC C6.1 mostró una variabilidad notable según el tamaño de la ventana espacial, aunque la ventana temporal no tuvo un impacto considerable. Se identificaron dos grupos de sitios: (i) La Paz y Buenos Aires, con menores niveles de AOD, menor desempeño y sesgo positivo; y (ii) São Paulo, Santiago y Ciudad de México, con mayores niveles de AOD, mejor desempeño y sesgo negativo. MAIAC C6.1 mostró una mejora en la reducción del sesgo, aunque sin cambios significativos en R2 o RMSE respecto de C6.0. En comparación con MODIS DT, MAIAC C6.1 presentó mayor precisión y menor sesgo, ya que MODIS sobreestimó la AOD en todos los sitios. A pesar de los avances en productos de alta resolución, persisten limitaciones en la cobertura de datos e incertidumbres, especialmente en áreas urbanas de América Latina. Satellite-derived aerosol optical depth (AOD) is a key indicator for expanding spatial coverage in air quality studies, particularly for estimating PM2.5 concentrations. However, validation of high-resolution AOD products remains limited in Latin American urban environments, which are characterized by complex aerosol dynamics and sparse ground-based monitoring. In this study, we evaluated the performance of MAIAC C6.1 AOD in six densely populated Latin American cities (São Paulo, Santiago, Buenos Aires, Medellín, La Paz, and Mexico City) from 2015 to 2022, using the AERONET network as a reference. MAIAC C6.1 performance was also compared with the previous version (C6.0) and MODIS DT to analyze differences in spatial resolution and assess performance improvements. A lack of ground-level AOD was observed, especially in Medellín and São Paulo, along with low average levels (AOD < 0.2) in La Paz and Buenos Aires. MAIAC C6.1 performance showed notable variability depending on the spatial window size, although no considerable impact was seen in the temporal window. Two site groups were identified: (i) La Paz and Buenos Aires, with lower AOD levels, lower performance, and positive bias; and (ii) São Paulo, Santiago, and Mexico City, with higher AOD levels, better performance, and negative bias. MAIAC C6.1 showed improvement in bias reduction, but no significant changes in R2 or RMSE compared to C6.0. Compared to MODIS DT, MAIAC C6.1 exhibited greater accuracy and lower bias, with MODIS overestimating AOD across all sites. Despite advances with high-resolution products, limitations in data coverage and uncertainty persist, especially in urban Latin American areas.
Towards an Ecohydrometeorological Monitoring System for Chile: A Scientific-Technical Proposal
(2025) Balocchi, Francisco; Salas-Eljatib, Cristian; Fernández, M. Paulina; Hervé-Fernández, Pedro; Iroumé, Andrés; Rivera, Diego; Olmedo, Guillermo F.; Arumí, José Luis; Briones, Raúl; Ramírez de Arellano, Pablo; Barra, Ricardo O.
Chile, con su amplia diversidad ecológica y geográfica, enfrenta desafíos ambientales que demandan una comprensión integrada de sus ecosistemas. Propusimos un enfoque de investigación donde las cuencas, como unidad principal de estudio, se complementaban con observaciones en distintos niveles de escala (desde el individuo, parcelas hasta cuencas). Este modelo se inspiró en experiencias internacionales exitosas que demostraron la relevancia de estudios prolongados y sitios representativos para la gestión sustentable de los recursos naturales. Observamos que los esfuerzos existentes (públicos y privados) solían ser puntuales, geográficamente dispersos y de corta duración temporal. Además, la falta de estandarización metodológica y bases de datos compartidas dificultaba el uso científico e informativo de la información. Si bien existían redes de sitios de monitoreo en algunos ecosistemas, éstas operaban de manera poco articulada y sin un centro de gobernanza que facilitara su coordinación, incluyendo la integración de disciplinas como hidrología, ecología, ciencias forestales, ciencias sociales y economía, todas indispensables para abordar problemas ambientales complejos. Dada la relevancia del cambio climático en la discusión nacional y global, propusimos un Sistema de Monitoreo Ecohidrometeorológico Universal (SIMUEN). El sistema se fundamentó en unidades hidrometeorológicas y se planteó con distintos niveles de monitoreo (desde individuos hasta cuencas), todos coordinados bajo un set mínimo de variables esenciales y metodologías estándar. De esta manera, buscamos no solo mejorar la respuesta ante eventos climáticos extremos, sino también generar bases científicas sólidas para la gestión y conservación de los recursos naturales, asegurando el bienestar de las generaciones futuras.
Hydrosocial power and territorial transformation: a case study of the Longaví River sub-basin in south-central Chile
(2025) Salgado-Vargas, Marcela; Lillo-Saavedra, Mario; Sanhueza, Fabian; Cisterna-Roa, Valentina I.; Somos- Valenzuela, Marcelo; Rivera, Diego
This article examines the configuration of hydrosocial territories (HST) and hydrosocial power (HSP) in the Longaví River sub-basin of south-central Chile. Drawing on land-use change analysis, documentary review, and interviews with key actors, we characterize how agricultural intensification and forestry expansion have reshaped both landscapes and water governance over the past three decades. The results show that HSP operates through infrastructure, discourses, and institutions that concentrate water rights and decision-making power in the hands of a few dominant actors. These dynamics reinforce historical and colonial configurations of HST, reproducing socio-environmental inequalities and marginalizing small-scale farmers and local communities. Such path-dependent processes not only constrain the emergence of alternative governance arrangements but also undermine the sustainability of water resource management amid increasing scarcity. By tracing socio-spatial dynamics, the study contributes to understanding how power asymmetries are embedded in hydrosocial relations and discusses their implications for advancing more equitable water governance in Chile and similar contexts.
Risk Management Model for Tailings Storage Facilities in Chile: An Approach from Geological and Mining Engineering and the Regulatory Framework
(2025) Vinet, Leslie; Valdés-González, Héctor; Calderón, Mauricio
Despite technological advancements in mining, Chile lacks comprehensive risk management models for tailings storage facilities (TSFs), which hinders the prevention and mitigation of structural and environmental risks. This study aims to develop an integrated risk management model for TSFs in Chile, combining geological and mining engineering with an updated regulatory framework to enhance safety and reduce environmental impacts. The research adopts a mixed-methods approach. Qualitatively, it draws on 10 semi-structured interviews with engineers, geologists, academics, and professionals from the Chilean mining industry, selected through purposive sampling, to explore how and why the current risk management model should be improved. Quantitatively, it analyzes data from 303 surveys assessing the existing regulatory framework, a proposed new regulatory decree for Chile, and key variables to be considered in TSF risk management. The results present a new model that integrates geochemical and geotechnical characterization, process variables, in situ sensors, remote sensing, and artificial intelligence to generate dynamic risk indicators and early warning systems throughout the life cycle of the facility, including closure and liability valuation. Its multiscale design, adaptable to seismic and hydrogeological conditions and suitable for small- and medium-scale mining, overcomes existing static and fragmented approaches, enabling more effective decision-making with a focus on environmental and community safety. The study concludes that the model provides a robust and coherent tool for TSF risk management by integrating technical expertise, the current regulatory framework, and the management of key variables that enhance the ability to anticipate and mitigate structural and environmental risks.
A Network Theory Approach to Assessing Environmental Sustainability in the Cruz Grande Region, Guerrero, Mexico
(2025) Lucrecio, Luis; Bosch, Paul; Molina, Edil; Rosas, José; Sigarreta, José
Traditional composite indicators for the study of sustainability often obscure the complex network of relationships among individual indicators, functioning as black boxes that fail to diagnose the underlying structural and functional weaknesses of the system. The objective of this research is to develop and apply a complementary approach grounded in network theory to diagnose and evaluate the structural and functional cohesion of environmental indicator systems. We developed a study that combines the Principal Component Analysis (PCA) method with network theory to comprehensively analyze the indicator system. The core of this contribution is the development of the 𝑀𝑜(𝐺) index, designed to quantify the structural–functional cohesion of an indicator network. This approach is applied to an environmental dataset of 19 indicators for Cruz Grande, Guerrero, Mexico (2010–2023). The results reveal that although the indicator network is relatively dense (𝑑=0.6199), its structural–functional cohesion is low (𝑀𝑜(𝐺)=520.68), placing the region in the Fair category. This result provides an explanation for the sustained decline of the system, as shown by the PCA-based Regional Environmental Sustainability Index. We conclude that this approach is a complementary tool for diagnosing and evaluating environmental systems, enabling the detection of vulnerabilities that remain invisible to conventional aggregation methods.
Shifting dry spells in Central Chile: Implications for agriculturalwater planning
(2025) Latoja, Daniela; Rivera, Diego; Lillo, Mario; Godoy-Faúndez, Alex
Chile’s agricultural production occurs in a highly variable Mediterranean climate and faces declining annual precipitation trends as well as growing competition from other uses. Water availability for agriculture depends on winter precipitation; however, a more even distribution of precipitation throughout the year would better support agricultural planning and management. We examine the occurrence, frequency, and trends of dry spells in Central Chile (32˚–40˚ S) as a proxy for changes in the timing of dry-wet seasons, using a gridded daily precipitation dataset spanning the period from 1960 to 2021. Our results indicate a significant increase in dry spells (+1 event/decade), but shorter (−2 days/event), and a significant decrease in precipitation per wet spell (−2 mm/event/decade). Findings suggest that changes in dry spells should also be considered in planning and policy, as some regions may be experiencing water shortages due to shifts in timing and access, rather than simply having less water. Plain Language Summary Chile’s agriculture occurs in a region with variable precipitation and temperature year-to-year. Water for farming mainly comes from winter precipitation, but better year-round distribution is needed for effective planning. We analyzed the occurrence of consecutive dry days during the fall-winter and spring-summer seasons. We found that there has been an increase in dry spells, as well as a decrease in precipitation volume per wet spell. Changes in dry spells should be considered in agricultural planning and policy, as some regions may face water shortages due to timing and access issues, in addition to reduced water availability.
Evaluating Smart Building Features for Fire, Electrical, and Life Safety: A Rapid Human-LLM Framework for Literature Review and Research Mapping
(2025) Leiva-Araos, Andrés; Kalasapudi, Vamsi; Jiang, Aiyin; Kaushal, Hemani
The rapid integration of smart technologies into modern buildings is fundamentally transforming fire, electrical, and life safety (FELS) systems. This paper introduces a hybrid Human–Large Language Model (LLM) framework designed to efficiently conduct large-scale literature reviews, systematically map existing research, and identify critical knowledge gaps in smart building safety. Leveraging advanced LLMs for high-throughput summarization, topic modeling, and gap analysis, combined with expert validation, this method ensures both scalability and domain-specific rigor. The study analyzes 1,409 publications retrieved from Scopus, culminating in a refined corpus of 83 high-quality articles categorized into nine thematic clusters, including advanced sensing technologies, automation, enhanced connectivity, digital twins, cybersecurity, standard compliance, sustainability, specialized applications, and decision-making in disaster response. Detailed gap analyses reveal significant challenges related to realworld validation of AI-based systems, interoperability among IoT devices, cybersecurity vulnerabilities, and the need for dynamic evacuation and hazard modeling. The resulting knowledge map and research roadmap provide actionable insights for researchers, practitioners, and policymakers aiming to advance safer, smarter, and more resilient built environments. The proposed framework demonstrates how AI-assisted methodologies can accelerate knowledge synthesis while preserving analytical depth, offering a scalable solution for rapidly evolving interdisciplinary research domains.
Towards a Circular Fashion Future: A Textile Revalorization Model Combining Public and Expert Insights from Chile
(2025) Palma, Cristian D.; Cabello, Priscilla
The global textile industry has a significant environmental impact, driven by fast fashion and rising consumption, which leads to large amounts of waste. In Chile, this problem is especially visible, with thousands of tons of discarded clothing accumulating in open areas and landfills. This study explores how to design a practical textile revalorization system grounded in local reality. We used a qualitative mixed-methods approach, combining semi-structured interviews with six experts in textile circularity and an online survey completed by 328 people. Thematic analysis revealed low public awareness of textile recycling, limited consumer participation, and major structural barriers, including scarce infrastructure and unclear regulations. Experts emphasized the importance of coordinated action among government, industry, and grassroots recyclers, while survey respondents highlighted the need for education and easier recycling options. Based on these insights, we propose an integrated framework that combines education campaigns, better recycling systems, and formal recognition of informal recyclers’ work. While centered on Chile, the study offers ideas that could support textile circularity efforts in other countries facing similar challenges. By merging expert knowledge with everyday public perspectives, the approach helps design more realistic and socially grounded solutions for textile waste management. As with many exploratory frameworks, external validation remains a necessary step for future research to strengthen its robustness and applicability.
Resolving Crustal and Subcrustal Dynamic Sources in Continental Arc Magmas: The Cenozoic Andean Arc of Central Chile
(2026) Muñoz, M.; Fanning, C.M.; Tapia, F.; Payacán, I.; Fuentes, F.; Farías, M.; Charrier, R.; Polvé, M.; Quiñones, S.; Deckart, K.; Fock, A.
The Andean margin of Central Chile (∼32°40′–34°30′S) records abundant Cenozoic arc magmatic activity with variable compositional characteristics. This is examined through the analysis of an extensive database of new and published whole-rock geochemistry and Sr-Nd isotopic compositions, in addition to zircon Hf and O isotopic compositions. The whole-rock data record an increasing assimilation of continental crust material that developed through the compressional regime set in the margin in the Early Miocene that led to the construction of the modern Andes. The same is recorded by the Hf and O isotopic compositions, but these also allow identification of components involved in the magma genesis: (a) the sub arc mantle derived primary magmas, (b) a late Paleozoic—Early Triassic crystalline component, as that currently outcropping immediately to the east of the study area, (c) a deep enriched component, which likely corresponds to the Cuyania terrane, a Grenville age basement recognized further east in this Andean region, and (d) a deep juvenile low-δ18O component, interpreted here as basement with oceanic crust affinities. This latter component reveals a possible composite nature for the Chilenia terrane, the postulated Grenville age basement in the region. The Cenozoic Andean arc magmas correspond to the differentiated products of an extensive intra-crustal re-working, taking place along tens of kilometers below their emplacement level, and whose main imprint is on the magmatic isotopic composition. Our results document the role of the continental crust, particularly regarding its evolving architecture and constitution, over the composition of arc magmas.
Coordinated Truck Loading and Routing Problem: A Forestry Logistics Case Study
(2025) Oliva, Cristian; Cepeda, Manuel; Muñoz, Sebastián
This study addresses a real-world logistics problem in forestry operations: the distribution of plants from cultivation centers to planting sites under strict delivery time windows and limited depot resources. We introduce the Coordinated Truck Loading and Routing Problem (CTLRP), an extension of the classical Vehicle Routing Problem with Time Windows (VRPTW) that integrates routing decisions with truck loading schedules at a single depot with constrained capacity. To solve this NP-hard problem, we develop a metaheuristic algorithm based on Ant Colony Optimization (ACO), enhanced with a global memory system and a novel stochastic return rule that allows trucks to return to the depot when additional deliveries are suboptimal. Parameter calibration experiments are conducted to determine optimal values for the return probability and ant population size. The algorithm is tested on a real forestry dispatch scenario over six working days. The results show that an Ant Colony System (ACS–CTLRP) algorithm reduces total distance traveled by 23%, travel time by 22%, and the number of trucks used by 13 units, while increasing fleet utilization from 54% to 83%. These findings demonstrate that the proposed method significantly outperforms current company planning and offers a transferable framework for depot-constrained routing problems in time-sensitive distribution environments.
Microbial and Geochemical Diversity of Laguna Timone, an Extreme Hypersaline Crater Lake in Patagonia (52° S)
(2025) Henríquez, Carolina; Pérez-Donoso, José M.; Bruna, Nicolás; Calderón, Mauricio; Fadel Cury, Leonardo; Quezada, Paulo; Athayde, Gustavo; Oyarzún, Poldie; Bahniuk, Anelize
Extreme environments, such as hypersaline habitats, hot springs, deep-sea hydrothermal vents, glaciers, and permafrost, provide diverse ecological niches for studying microbial evolution. However, knowledge of microbial communities in extreme environments at high southern latitudes remains limited, aside from Antarctica. Laguna Timone is a hypersaline crater lake located in a Pleistocene maar of the Pali Aike Volcanic Field, southern Patagonia; the lake was formed during basaltic eruptions in a periglacial setting. Here, we report the first integrative characterization of microbial communities from biofilms and microbial mats in this lake using high-throughput 16S rRNA and ITS gene sequencing, along with mineralogical and hydrochemical analyses of water, sediments, and carbonates. Bacterial communities were dominated by the genera Enterobacterales ASV1, Pseudomonas, Oscillatoria, Nodularia, and Belliella, with site-specific assemblages. Fungal communities included Laetinaevia, Ilyonectria, Thelebolus, Plectosphaerella, and Acrostalagmus, each showing distinct distribution patterns. These baseline data contribute to understanding microbial dynamics in hypersaline maar environments and support future investigations. This integrative approach highlights key microbe–mineral relationships and underscores the potential of Laguna Timone as a natural laboratory for exploring biosignature formation and microbial adaptation in chemically extreme environments, both on early Earth and potentially beyond.
Environmental Stressors Modulating Seasonal and Daily Carbon Dioxide Assimilation and Productivity in Lessonia spicata
(2025) Troncoso, Macarena; Fleming, Zoë; Figueroa, Félix L.; Korbee, Nathalie; Durán, Ronald; Navarrete, Camilo; Rivera, Cecilia; Celis-Plá, Paula S. M.
Carbon dioxide (CO2) emissions due to human activities are responsible for approximately 80% of the drivers of global warming, resulting in a 1.1 °C increase above pre-industrial temperatures. This study quantified the CO2 assimilation and productivity of the brown macroalgae Lessonia spicata in the central Pacific coast of Chile, across seasonal and daily cycles, under different environmental stressors, such as temperature and solar irradiance. Measurements were performed using an infra-red gas analysis (IRGA) instrument which had a chamber allowing for precise quantification of CO2 concentrations; additional photophysiological and biochemical responses were also measured. CO2 assimilation, along with the productivity and biosynthesis of proteins and lipids, increased during the spring, coinciding with moderate temperatures (~14 °C) and high photosynthetically active radiation (PAR). Furthermore, the increased production of photoprotective and antioxidant compounds, including phenolic compounds, and carotenoids, along with the enhancement of non-photochemical quenching (NPQ), contribute to the effective photoacclimation strategies of L. spicata. Principal component analysis (PCA) revealed seasonal associations between productivity, reactive oxygen species (ROSs), and biochemical indicators, particularly during the spring and summer. These associations, further supported by Pearson correlation analyses, suggest a high but seasonally constrained photoacclimation capacity. In contrast, the reduced productivity and photoprotection observed in the summer suggest increased physiological vulnerability to heat and light stress. Overall, our findings position L. spicata as a promising nature-based solution for climate change mitigation.
Reviews and syntheses: Current perspectives on biosphere research 2024–2025 – eight findings from ecology, sociology, and economics
(2025) Bohn, Friedrich J.; Bastos, Ana; Martin, Romina; Rammig, Anja; Koh, Niak Sian; Sioen, Giles B.; Buscher, Bram; Carver, Louise; DeClerck, Fabrice; Drupp, Moritz; Fletcher, Robert; Forrest, Matthew; Gasparatos, Alexandros; Godoy Faúndez, Alex; Hagedorn, Gregor; Hänsel, Martin C.; Hetzer, Jessica; Hickler, Thomas; Krug, Cornelia B.; Koot, Stasja; Xiuzhen Li, Xiuzhen; Luers, Amy; Matevich, Shelby; Matthews, H. Damon; Meier, Ina C.; Migliavacca, Mirco; Mohamed, Awaz; Sungmin O; Obura, David; Orlove, Ben; Orth, Rene; Pereira, Laura; Reichstein, Markus; Thakholi, Lerato; Verburg, Peter H.; Yoshida, Yuki
This review of recent advances in biosphere research aims to provide information on eight selected themes related to changes in biodiversity, ecosystem functioning, social and economic interactions with ecosystems, and the impacts of climate change on the biosphere. An interdisciplinary panel of experts selected these eight themes from a public survey based on relevance and scientific evidence that have the potential to guide future actions as well as inspire future research questions. Our focus is on the interactions between climate, biosphere, and society and on strategies to sustain, restore, or promote ecosystems and their services. The themes focus on innovative opportunities for coastal habitats, forest linkages to droughts, and increasing fire risks. We further discuss nature-based carbon dioxide removal (CDR) implementation risks and the share of (semi-)natural habitats in the landscape. Finally, we highlight the importance of comprehensive international policy packages and the social–economic value of ecosystems in the future and present the idea of convivial conservation. Based on an analysis of these eight topics, we have synthesized four overarching insights: (i) improve mechanisms of inclusive decision-making, (ii) establish and strengthen incentives for sustainable practices, (iii) measure and share regional features, and finally (iv) adopt long-lasting holistic landscape management strategies. This review emphasizes that the interlinked challenges for ecosystems, including the socio-economic dimensions, require interdisciplinary and integrative approaches to develop effective and sustainable solutions.
Current Status, Trends, and Future Directions in Chilean Air Quality: A Data-Driven Perspective
(2025) Basoa, Kevin; Fleming, Zoë; Leiva, Manuel A.; Concha, Carolina; Menares, Camilo
Air pollution is one of the main problems facing humanity today. Megacities and large urban areas are pollution hotspots. Measuring pollutants and recording these measurements is key to developing effective strategies to reduce the pollution levels to which people are exposed. However, air quality monitoring presents significant challenges (e.g., investment costs, maintenance), which can lead to limited monitoring equipment. Despite this, Chile has an extensive air quality monitoring network, known as the National Air Quality Information System (SINCA in Spanish). This network has more than 200 monitoring stations that measure, record, and display information on pollution levels in different locations in Chile. In this study, all the information available from the SINCA network was systematized to evaluate the completeness of the records and the current trends of several pollutants in Chile. The main results show that most measurements focus on particulate matter and sulfur dioxide concentrations, and many of the measurement stations are located in the central part of the country (32° S–38° S). However, by splitting the data into five macrozones, one can see the regional air quality characteristics and changes. Furthermore, there are significant data gaps at some monitoring stations, which makes it difficult to elaborate a robust analysis. Regarding pollution levels, a significant decrease is observed for the peak Particulate Matter (PM2.5) concentrations, with decreases of nearly 40% compared to concentrations at the beginning of the 2000s. This is consistent with the concentration trends, which show negative trends in most cases.
Applying the Analytic Hierarchy Process (AHP) to Accessible Housing: A Multi-Disability Perspective
(2025) Valderrama-Ulloa, Claudia; Ferrada, Ximena; Herrera, Felipe
Accessible housing plays a vital role in promoting independent living and quality of life for people with disabilities. However, the existing design standards often fail to address the specific needs of diverse disability groups. This study aims to establish architectural and habitability criteria for housing adapted to various disabilities, including wheelchair users, individuals with achondroplasia (little people), Autism Spectrum Disorder (ASD) and Down syndrome, individuals with visual and hearing impairments, and older adults, by integrating international frameworks and prior research. The Analytic Hierarchy Process (AHP) was used to prioritize key factors in the housing design. The factors analyzed included autonomy, independence, safety, comfort, communication, and mobility. Findings reveal that autonomy consistently emerged as the most relevant criterion across groups, particularly for older adults (61.8%), wheelchair users (83%) and little people (64%). Secondary priorities varied: mobility was emphasized by wheelchair users (77%), communication by visually impaired individuals (64%), and comfort by deaf and hard of hearing participants (43%). The results underscore the need for housing solutions that reflect the priorities of each disability group. This study contributes by validating user-centered design criteria and offering a framework to guide inclusive housing policies and practices. By highlighting needs, it bridges the gap between generic accessibility standards and design. These findings support policy development and enrich the literature by incorporating unique resident-centered perspectives and overlooked indicators of housing accessibility and inclusive residential design.

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