University of Chile

Background Zoonotic viruses, such as Orthohantavirus andesense (ANDV; the causative agent of hantavirus cardiopulmonary syndrome, HCPS), pose significant public health risks at the human-wildlife interface. Understanding their eco-epidemiological dynamics is critical for elucidating the interplay between reservoir hosts, environmental factors, and spillover to humans. In Chile, the long-tailed pygmy rice rat ( Oligoryzomys longicaudatus ) serves as the primary reservoir for ANDV. This study investigates whether protected areas (PA), which typically support higher biodiversity and stable ecosystems, exhibit lower ANDV seroprevalence compared to unprotected areas (UPA), where anthropogenic disturbances may alter host-pathogen dynamics. Methodology Between 2001–2008, we conducted small mammal sampling across 22 sites (11 PA and 11 UPA) in natural landscapes of Chile. Seroprevalence of ANDV was assessed via strip immunoassay, while small mammal diversity was evaluated using standardized trapping protocols and diversity indices. We used similarity percentage analysis to identify species contributing to community dissimilarities and applied Renyi diversity profiles to compare small mammal diversity between area types. Main Findings We captured 627 small mammals (PA: 331, 14 species; UPA: 296, 10 species) across 12,898 trap-nights. Seroprevalence in O. longicaudatus was identical in PA and UPA (9.5%). No significant differences were found in the relative abundance or seropositivity of O. longicaudatus between area types. Ecological indices (Shannon-Wiener, Simpson, richness, evenness) and community composition (ANOSIM) also showed no significant differences. Rényi profiles indicated marginally higher diversity in PA, driven by greater richness and evenness. Conclusions These findings suggest that ecological factors, such as habitat type, climatic conditions, and/or human behavior, may play a more critical role in shaping viral prevalence than protection status alone. The study underscores the necessity for consistent public health interventions to mitigate the risk of hantavirus cardiopulmonary syndrome across all environments, particularly in regions where human activities intersect with natural habitats.

We extend the notions of nonautonomous dynamics to arbitrary groups, through groupoid morphisms. This also presents a generalization of classic dynamical systems and group actions. We introduce the structure of cotranslations, as a specific kind of groupoid morphism, and establish a correspondence between cotranslations and skew-products. We give applications of cotranslations to nonautonomous equations, both in differences and differential. We also give several other examples on different groups. Our results delve into the differentiability of cotranslations, along with dimension invariance and diagonalization, utilizing a generalized notion of kinematic similarity.

We provide a new type of proof for known or new Gohberg lemmas for pseudodifferential operators on Abelian locally compact groups X. We use C*-algebraic techniques, which also give spectral results to which the Gohberg lemma is just a corollary. These results extend most of those appearing in the literature in various directions. In particular, compactness or a Lie structure are not needed. The ideal of all the compact operators in L2(X) is replaced by all the ideals having a crossed product structure, which is a consistent generalization. We also indicate several new examples, mostly connected to specific behaviors of functions on the dual Ξ of X.

This chapter reviews environmental psychology’s use of methodologies and the challenges associated with an interdisciplinary field. Research has traditionally preferred quantitative methods, especially in the Global North, using surveys, psychometric developments, and experiments to study the relationship between people and their environments. However, the growing importance of qualitative methods has been recognized, especially in community environmental psychology in Latin America, for the study of underrepresented communities and complex experiences. These approaches, which are less inclined to reflect hegemonic visions, explore the complexity of experiences and meanings through in-depth interviews, observation, text analysis, and spatial methodologies, such as walking interviews and collective mapping. After reviewing some of the most common methods in the field, the final discussion addresses the persistent quantitative–qualitative binarism and the need to overcome a merely technical coexistence and achieve critical reflexivity on the onto-epistemic, ethical, and political implications of each approach. The importance of considering scientific investigative rigor based on epistemic relevance and ethical responsibility is underscored, in addition to the usefulness of methodological triangulation and caution with irreflexive integration of mixed methods. Last, a “methodological imagination” for environmental psychology is proposed, which connects the individual experience with broad social dynamics, inquiring into silenced knowledge and strengthening transdisciplinary approaches and the understanding of concepts like territory and community.

The application of π‐electron localization function (ELFπ) bifurcation topology is extended here to assess excited state aromaticity (ESA). The analysis employs two topological descriptors: the ring‐closure bifurcation value (RCBV), which marks the onset of annular π‐delocalization, and the span of bifurcation values (DBV), which measures its uniformity. Thresholds proposed for ground‐state systems are applied here, while values below the aromatic limit (RCBV < 0.70) are interpreted with caution, since delocalization‐based indices cannot unambiguously separate nonaromatic from antiaromatic cases. The methodology is applied to benzene, cyclobutadiene, cyclooctatetraene, and naphthalene across their S0, S1, and T1 states. As benchmarks, the nonaromatic 1,4‐dihydrobenzene in its ground state is also included, and the problematic case of borazine is discussed based on literature values. ELFπ descriptors reproduce the expected aromatic and antiaromatic trends and complement magnetic and electronic indices reported in the literature, while highlighting ambiguous regimes where additional analysis is required. Overall, ELFπ bifurcation analysis provides a chemically meaningful and computationally efficient framework for probing aromaticity in excited states, offering a topological perspective that complements conventional energetic and magnetic descriptors.

This study reports the effect of diethylzinc (DEZ) and trimethylaluminium (TMA) functionalization on polyamide-6 (PA6) films using the vapour-phase metalation (VPM) process within an atomic layer deposition (ALD) chamber. The resulting zinc- and aluminium-functionalized films are referred to henceforth as PA6-Zn and PA6-Al, respectively. Biocompatibility was preliminarily assessed via C2C12 cytotoxicity testing. Reaction mechanisms were examined using density functional theory, electrostatic potential maps, Mulliken charge distribution, and X-ray photoelectron spectroscopy, revealing interactions between metal precursors and PA6 amide groups. DFT confirmed α-PA6 as the dominant structure and identified reactive sites influencing functionalization pathways. Structural and morphological changes were analysed via environmental scanning electron microscopy and X-ray diffraction. ESEM showed Zn-functionalized PA6 forming strand-like structures, while Al-functionalized PA6 developed pore-like cavities. XRD indicated increased crystallinity upon metalation, with the α/γ crystallite size ratio following the trend: PA6-Al > PA6-Zn > PA6. Spectroscopic analysis using infrared and Raman microscopy, along with UV–visible spectroscopy, highlighted modifications in chemical bonding and polymorphism, aligning with DFT predictions. Al functionalization had a stronger influence on PA6’s spectroscopic and some mechanical properties, whereas Zn functionalization notably enhanced failure strain. Barrier and mechanical properties were evaluated, showing that Zn-functionalized PA6 exhibited superior oxygen permeability, while both metal-modified films improved water vapour transmission rates compared to bare PA6. Cytotoxicity testing revealed enhanced C2C12 cell proliferation in the order PA6-Al > PA6-Zn > PA6, suggesting VPM-modified PA6 as a promising material for biomedical applications. Graphical Abstract

Background Individuals with Duchenne Muscular Dystrophy (DMD) exhibit respiratory muscle changes leading to fatigue and weakness, and assessing relaxation rates and contractile properties may help detect early fatigue. Aim To non-invasively assess inspiratory muscle relaxation and contractile rates using sniff nasal inspiratory pressure (SNIP) parameters in DMD subjects and compare them with matched healthy controls. Methods A case-control study of 32 DMD male subjects and 32 age-matched healthy controls (12.7 ± 5.1 years). All subjects underwent spirometry, maximal respiratory pressures, and SNIP test. We calculated the maximum relaxation rate (MRR), decay constant (τ), and maximum rate of pressure development (MRPD) from the SNIP curve. Results The DMD group had significantly lower MRR (5.9 [5.1–6.9] vs. 8 [6.9–10.3] %/ms, p = 0.001), lower MRPD (−0.38 [−0.47 to −0.26] vs. −0.62 [−0.52 to −0.80] cmH2O/ms−1, p = 0.001), and higher τ (65.7 [50.7–78.1] vs. 40.5 [30.2–48.7] ms, p = 0.001). ROC curves showed that SNIP parameters effectively distinguish DMD from healthy subjects (SNIP [AUC 0.94, p < 0.001], MRR [AUC 0.86, p < 0.001], τ [AUC 0.92, p < 0.001], and MRPD [AUC 0.89, p < 0.001]). Conclusions DMD subjects show impaired inspiratory muscle contraction and relaxation, indicating early muscle weakness or fatigue. SNIP-derived parameters may help in the early identification of inspiratory muscle dysfunction in DMD, potentially contributing to clinical detection and intervention.

Background The microbiota‒gut‒brain axis modulates pigs’ stress response, behavior, and overall welfare. Stressful management practices can disrupt gut microbiota (GM), negatively impacting pigs' health and welfare. This study evaluated how the quality of human handling influences stress-related physiological responses, productive performance, and gut microbiota (GM) composition in pigs during the nursery phase. Results Female pigs (n= 36, 21 days old) were randomly assigned to three experimental groups (12 pigs/group, four pens per treatment): positive human handling (PHH), negative human handling (NHH), and a control group (CG). The PHH group experienced gentle tactile interactions, whereas the NHH group was subjected to chronic intermittent stress through acute stressors, and the CG group received minimal handling for routine practices. Hair cortisol concentrations were measured as an indicator of chronic stress (days 15 and 64). Productive performance was assessed through body weight (BW), average daily gain (ADG), average daily feed intake (ADFI), and feed conversion (FC). Fecal samples were collected at baseline (T0, day 16), mid-study (T1, day 37), and end of the study (T2, day 65) and analyzed using 16S rRNA gene amplicon sequencing to assess GM changes over time. Pigs in the PHH group showed a significant reduction in cortisol levels from baseline to post-treatment (P < 0.0001), while no significant changes were observed in the NHH group (P = 0.26). A smaller but significant decrease was also detected in the CG group (P = 0.001). PHH pigs had higher BW (P = 0.0009) and ADG (P = 0.03) during the later growth phase compared to NHH pigs. At T2, PHH pigs exhibited greater diversity and richness compared to NHH pigs, indicating a restorative effect on GM composition. Differential abundance analyses identified four bacterial genera that distinguished treatment groups: Blautia , Megasphaera , and Subdoligranulum were enriched in PHH pigs, while Terrisporobacter was enriched in NHH pigs. Additionally, bacterial interaction networks exhibited the least complex network in the NHH group, with ecological associations primarily involving Clostridium and Terrisporobacter . Conclusions The quality of human handling influenced stress physiology, performance, and gut microbiota in pigs. Positive handling reduced cortisol levels, improved growth, and promoted microbial diversity, while negative handling was linked to decreased performance and reduced microbial network complexity. These results highlight the potential of positive interactions to enhance welfare and productivity, and identify specific bacterial genera as potential biomarkers differentiating negative and positive handling conditions.

Understanding the genetic architecture of economically important traits is essential for the design and implementation of efficient breeding programs. Here, we analysed 3,653 Eastern oysters (Crassostrea virginica) from 62 crossing groups and 307 full-sib families, all genotyped with a 200 K SNP array, to (i) estimate heritability and genetic correlations for six growth-related traits, (ii) detect quantitative trait loci (QTL) and candidate genes, and (iii) compare the accuracy of pedigree- (PBLUP) versus genomic-based (GBLUP) predictions across marker densities, selection strategies (physical distance (PD) versus linkage disequilibrium (LD) and phenotype-based genotyping strategies. SNP-based Heritabilities ranged from 0.33 to 0.56, and genetic correlations among traits exceeded 0.61, indicating strong pleiotropy. GWAS revealed a polygenic architecture with a shared QTL on chromosome 2; the top SNP explained ≤ 1.1% of phenotypic variance. Except for the 0.5 K LD panel—where PBLUP was more accurate—and the 1 K LD panel—where both methods performed similarly—GBLUP outperformed PBLUP in all scenarios, with the greatest advantage observed for physically spaced (PD) panels. The highest accuracy (0.80) was achieved with the full 100 K SNP set. GBLUP models required panels containing ≥ 0.5 K PD (accuracy ≥ 0.55) or ≥ 2 K LD (accuracy ≥ 0.56) to significatively surpass PBLUP predictions. Training sets built from extreme phenotypes boosted accuracy in small to intermediate sample sizes (e.g., 0.74 at n = 1,500 with 5 K PD SNPs versus 0.53 under random sampling). These results provide novel insights into not only the genomic regions controlling growth in this species but also about the utility of PD-based SNP panels and balanced sampling designs for enhancing GS accuracy in C. virginica. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-025-12100-z.

Immersion in wilderness dominated by natural soundscapes can generate health-restoring effects. Inspired in this concept, urban green spaces can be designed to recreate the conditions of the natural environment so that their soundscapes produce these potential benefits for the population. The aim of this project is to develop a pilot experience of biophilic soundscape design in an urban open space currently dominated by the perception of technological noise, in order to increase the well-being of potential visitors. The design of a pilot urban park with high quality soundscapes will serve as a basis for guidelines that incorporate these dimensions into the regulatory framework and allow for innovation in green infrastructure design standards.

The user-centered soundscape design tool City Ditty has been supplemented with local data from Santiago, Chile, to be used in the design of an urban park in which the perception of natural soundscapes dominates over other sound sources. This local data comprises a 3D model of the space, ambisonic recordings of urban background noise, 3D assets and recordings of sound sources (e.g. regional birds). This sketchpad tool is being adapted to local particularities to increase its performance in biophilic design interventions in the target area, and to be able to auralize the proposed 3D park models. These interventions arise from a design competition in interdisciplinary teams and their results are evaluated through individual auralization tests. The design proposal whose soundscape gets the highest subjective rating will be optimized by iterating listening tests and adjusting the design parameters. Once optimized, the final design model can be experienced at City Ditty through head-mounted VR binaural playback as well as an immersive multi-channel playback system.

LaFemina et al. (2025, https://doi.org/10.1029/2024JB030621) argue that the 2018 Sierra Negra eruption represents caldera resurgence based on uplift at the southern trapdoor fault in the caldera. We clarify that our original study (Shreve & Delgado, 2023, https://doi.org/10.1029/2023jb026437) focused exclusively on the co‐eruptive phase, not the entire decade‐long unrest sequence. We show that the eruption produced net caldera subsidence along the floor, not uplift, and that the observed co‐eruptive normal faulting is inconsistent with the definition of caldera resurgence as understood for felsic calderas. In contrast, the geophysical signals recorded during the eruption resemble those recorded during basaltic caldera collapses.

In the Coastal Cordillera of northern Chile, iron oxide-copper-gold (IOCG) deposits are spatially associated with Early Cretaceous intrusive rocks, though their genetic relationship remains enigmatic. We present zircon U–Pb dating and trace element analysis of intrusions in the world-class Mantoverde district to elucidate the magmatic evolution and controls on mineralization. Zircon geochemistry data indicate magmatism occurred in three main stages: Stage I (~ 138–134 Ma), Stage II (~ 131–125 Ma), and Stage III (~ 119–98 Ma). Stage I is interpreted as a precursor magmatic episode, with low Eu/Eu* values (~ 0.25), low ΔFMQ (–0.1), crystallization temperatures between 650 and 720 °C, and (Dy/Yb)N ratios of ~ 0.16. Stage II magmatism is characterized by distinctively low Eu/Eu* values (< 0.2), reduced conditions (ΔFMQ = − 1.4 to 0), higher temperatures (> 700 °C), and higher (Dy/Yb)N ratios (~ 0.2). The reduced nature of the Stage II magmas may be attributed to segregation of magnetite during an early iron oxide-apatite (IOA)-type mineralization. A sharp contrast is observed in Stage III, which is broadly coeval with copper mineralization at Mantoverde. This stage displays zircon Eu/Eu* values of > 0.4, oxidized signatures (ΔFMQ > + 0.8), lower temperatures (630–700 °C), and lower (Dy/Yb)N ratios (~ 0.1), i.e., typical of those found in porphyry copper intrusions. The change in magmatic conditions facilitated transport of copper and sulfur to form IOCG-type mineralization. The reported changes in magmatism are coeval with a regional tectonic reconfiguration to a more compressive setting, which likely influenced magmatic differentiation. As a result, conditions shifted from a shallower reservoir with low water accumulation to deeper levels characterized by multi-stage stagnant magmas with increased hydration levels. Our results provide further evidence that Andean IOCG deposits were the result of a two-stage process: an IOA-style mineralization related to reduced, water-poor magmatism, followed by an oxidized, water-rich magmatism responsible for the main copper mineralization.

Background and Aims Acaena integerrima and Embothrium coccineum are native plants colonizing volcanic deposits in southern South America. Both species can grow in poor nutrient availability, increasing their leaf nutrient status when growing together. Enhanced leaf P concentrations could be explained by cluster-root carboxylate exudation of E. coccineum; however higher leaf N in E. coccineum has an unknown origin and free-living N2-fixing microbes could be involved. Methods To test this possible mechanism, we conducted an experiment using volcanic material (pumice) and seedlings. We studied bacterial communities (16S rRNA and nifH) in the rhizosphere of E. coccineum and A. integerrima, both grown alone and together. To evaluate microbial communities, we used Polymerase Chain Reaction and Denaturing Gradient Gel Electrophoresis. We measured carboxylate-exudation, leaf nutrient concentrations (N, P) and leaf δ¹⁵N isotopic fractionation. Results The survival and shoot growth of A. integerrima was increased when grown combined. E. coccineum showed higher N and P concentrations when grown together than alone. Carboxylate-exudation showed faster rates of citrate from both species, being malate detected only from E. coccineum. Isotopic fractionation showed values close to zero in E. coccineum, being indicative of a biologically fixed N. The rhizosphere of E. coccineum alone exhibited the most distinct presence of 16S rRNA and nifH. Conclusions Our results show that the N2-fixing bacterial communities and δ¹⁵N indicate reliance on diazotrophic activity in E. coccineum rhizosphere. Additionally, A. integerrima appears to benefit from this N fixation and shows the importance of carboxylate exudation as strategy on colonizing plant species.

Pro‐environmental behavior approaches aim to minimize environmental degradation resulting from customer actions, a societal concern. This study aims to provide a complete overview of the trends regarding scientific research on pro‐environmental purchasing intentions over the last three decades. The objective is to identify years of evolution, the most relevant and influential keywords, articles, journals, universities, publishers, countries or regions, and authors. For this purpose, the work uses the Web of Science Core Collection database. It analyses a wide range of bibliometric indicators, including the number of publications and citations, citations per paper, the h‐index, and citation thresholds. The study also develops a graphical analysis of bibliographical material using the visualization of similarities (VOS) viewer software. We present a bibliometric analysis using evaluative and relational techniques, reviewing measures, associations, and cauterization from 1995 to 2023. Our findings reveal a notable convergence of consumer behavior and environmental responsibility since the 2000s. The findings suggest the identification of three clusters of pro‐environmental purchasing intention research: Customers' perception of the value of sustainable products, the Theory of Planned Behavior, and Willingness to pay. The number of publications on the theme has exponentially increased since 2017. Research on pro‐environmental purchasing intentions is conducted in various fields, including business, environmental sciences, green sustainable science and technology, environmental studies, and management. Therefore, this research provides a comprehensive understanding of patterns of pro‐environmental purchasing intentions, which can inform further research.

Background/Objectives: Ocular trauma (OT) and traumatic dental injuries (TDI) inflicted by police officers not only cause significant physical harm, but also psychological trauma. The clinical attention given by health care teams may induce revictimization or retraumatization phenomena, which affect the psychological status of the victim. The objective of this research is to bring to light the psychological experiences related to emergency care processes and rehabilitation of people affected by OT and TDI caused by police violence. Methods: Qualitative research was conducted based on in-depth interviews with eighteen people affected by OT or TDI during the social outbreak in Chile in 2019–2020. Data analysis was based on the principles of grounded theory. Results: Three main categories emerged: quality of interpersonal relationships with health care providers, expectations of care and treatment and psychological consequences. The findings show that retraumatization and revictimization arise from clinical care in the context of state violence. Conclusions: Revictimization and retraumatization are the most characteristic phenomena occurring in the health care of people affected by OT and TDI caused by police violence. The probability of their occurrence depends mainly on the interpersonal relationships established with the health care team and the management of patient expectations regarding health care.

Heteropagus (parasitic) twins are rare congenital anomalies characterized by a malformed parasitic twin attached to an otherwise normally developed host. Epignathus is a rare oropharyngeal mass that may represent a fetus-in-fetu and can result in life-threatening airway obstruction. We report the case of a preterm male neonate presenting with 2 fetiform masses: an intraoral epignathus obstructing the airway and a maxillary mass causing ocular proptosis. Surgical resection of the intraoral mass at 7 days of age restored airway patency. Histopathologic examination confirmed fetus-in-fetu with distinguishable fetal structures. Despite successful surgery, the presence of an encephalocele and extensive ischemic brain injury led to a decision to initiate palliative care. This case highlights the importance of early diagnosis and interdisciplinary surgical management in such complex presentations. Epignathus as a fetus-in-fetu remains exceedingly rare and may mimic teratomas. Compassionate, individualized care is essential in managing complex congenital anomalies.

Butyrate‐producing gut bacteria and luminal butyrate levels are reduced in Inflammatory Bowel Diseases (IBDs). Butyrate has anti‐inflammatory properties through mechanisms not well‐characterized in IBDs. Here, we determined the butyrate anti‐inflammatory effect on primary IBD tissues and intestinal cell models to identify key target cells and pathway(s) involved. Cytokines, monocarboxylate transporter‐1 (MCT1), G‐protein‐coupled receptor‐109A (GPR109A), and histone deacetylase‐3 (HDAC3) levels were analyzed in IBD and healthy tissues using cytometric bead arrays, RNA‐seq analysis and immunofluorescence. Inflammatory markers and phagocytosis in butyrate‐treated colonic organoids, primary monocytes or THP‐1 macrophages, were assessed by qPCR, flow cytometry and amikacin protection assays, when relevant combined with GPR109A or HDAC3 antagonists. Butyrate suppressed TNF and IL‐6 secretion by > 50% in ex vivo‐cultured inflamed IBD biopsies. MCT1 expression was reduced in inflamed epithelium and cytokine‐exposed organoids, while IL‐18 was reduced 0.5‐fold in organoids, and both were restored by butyrate, without suppressing pro‐inflammatory gene expression. GPR109A and HDAC3 were elevated in IBD tissues and upregulated by butyrate in cultured mucosa. Butyrate also suppressed IL‐6, TNF‐α, CD40, and CD80 by > 50% and enhanced adherent‐invasive Escherichia coli (AIEC) phagocytosis by 62% in monocytes/macrophages. Histone acetylation (H3K9ac) increased > 5‐fold, mimicking the HDAC inhibitor SAHA. Contrary, specific GPR109A inhibition and gene G‐protein‐coupled receptor inhibition did not alter butyrate's effects. Butyrate restores MCT1 and IL‐18 gene expression in inflamed epithelial cells, showing limited anti‐inflammatory effects. Instead, butyrate targets HDAC3 in mononuclear cells, suppressing inflammation in IBD gut mucosa. The cell‐type‐specific effects of butyrate offer mechanistic insights that support its therapeutic relevance in IBDs.

Understanding strawberry thermal resilience is crucial for optimizing cultivation in the face of climate change. However, its thermal niche remains underexplored. We assessed the thermal vulnerability of leaves and flowers in four day-neutral strawberry varieties cultivated in Chile and evaluated potential shifts in their suitable cultivation areas under warming scenarios. Tolerance to freezing, heat (LT50), and Thermal Tolerance Breadth (TTB) were determined, and habitat suitability was modeled using MaxEnt under two climate change projections and time periods. Heat LT50 of leaves and flowers was similar across strawberry varieties, averaging 56 °C. Conversely, the average freezing LT50 of flowers was 12 K less negative than that of leaves across varieties. The TTB of leaves was generally broader than that of flowers, except for San Andreas, with Monterrey displaying the broadest TTB difference (14.6 K). Climatic models indicated slight southward shifts in suitable cultivation areas under warming in Chile and globally. Nevertheless, the potential for strawberry cultivation in the more southern regions will depend on the development and implementation of cultivation strategies that effectively minimize the risk of freezing damage to the flowers. This highlights the need to plan cultivation areas according to each variety’s thermal tolerance to enhance resilience and sustainability in a changing climate.