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AERO-MAP: a data compilation and modeling approach to understand spatial variability in fine- and coarse-mode aerosol composition
No full textAerosol particles are an important part of the Earth climate system, and their concentrations are spatially and temporally heterogeneous, as well as being variable in size and composition. Particles can interact with incoming solar radiation and outgoing longwave radiation, change cloud properties, affect photochemistry, impact surface air quality, change the albedo of snow and ice, and modulate carbon dioxide uptake by the land and ocean. High particulate matter concentrations at the surface represent an important public health hazard. There are substantial data sets describing aerosol particles in the literature or in public health databases, but they have not been compiled for easy use by the climate and air quality modeling community. Here, we present a new compilation of PM2.5 and PM10 surface observations, including measurements of aerosol composition, focusing on the spatial variability across different observational stations. Climate modelers are constantly looking for multiple independent lines of evidence to verify their models, and in situ surface concentration measurements, taken at the level of human settlement, present a valuable source of information about aerosols and their human impacts complementarily to the column averages or integrals often retrieved from satellites. We demonstrate a method for comparing the data sets to outputs from global climate models that are the basis for projections of future climate and large-scale aerosol transport patterns that influence local air quality. Annual trends and seasonal cycles are discussed briefly and are included in the compilation. Overall, most of the planet or even the land fraction does not have sufficient observations of surface concentrations - and, especially, particle composition - to characterize and understand the current distribution of particles. Climate models without ammonium nitrate aerosols omit similar to 10 % of the globally averaged surface concentration of aerosol particles in both PM2.5 and PM10 size fractions, with up to 50 % of the surface concentrations not being included in some regions. In these regions, climate model aerosol forcing projections are likely to be incorrect as they do not include important trends in short-lived climate forcers
La dignidad del Trabajo: reflexiones en torno a su sentido
No full textHemos querido rescatar en el título del libro la “cualidad de digno” del trabajo. No lo hemos hecho con el afán de agotar todas las problemáticas que giran en torno a este tema, sino más bien, con el fin de detenernos a reflexionar sobre alguno de los temas más acuciantes de este primer cuarto de siglo. Es por esto por lo que hemos invitado a veintitrés autores a reflexionar en torno al trabajo y sus alcances". Los editores Desde siempre, el trabajo ha sido una parte esencial de la vida humana. Más allá de ser un medio para la subsistencia, tiene un sentido más profundo: dignificar al ser humano y darle un propósito, especialmente desde una visión cristiana que lo conecta con Dios y con el servicio a los demás. A lo largo de la historia, el concepto de trabajo ha evolucionado de manera significativa. Las revoluciones industriales cambiaron radicalmente la forma en que entendemos y enfrentamos el trabajo, y nos obligaron como sociedad a adaptarnos a esos cambios. Hoy, en plena cuarta Revolución Industrial, con la inteligencia artificial como protagonista, enfrentamos retos similares a los de siempre: ¿cómo podemos asegurar que el trabajo dignifique al ser humano y no lo convierta en un mero instrumento? Para reflexionar sobre estas preguntas, se ha reunido a veintitrés expertos de diversas disciplinas: historiadores, filósofos, educadores, médicos, ingenieros, psicólogos, teólogos, sacerdotes, abogados y economistas. A través de sus ensayos, analizan los desafíos actuales del trabajo y proponen soluciones desde sus diversas perspectivas. Este libro busca inspirar, provocar el diálogo y ofrecer respuestas a las preguntas más urgentes sobre el futuro del trabajo. Porque, al final, se trata de construir un mundo en el que el trabajo sea una fuente de dignidad para todos
Enhancing seismic performance of reinforced concrete dual wall-frame buildings: Integrating alternative modeling and design approaches
No full textThis study delves into two critical issues related to the seismic analysis and design of Chilean reinforced concrete dual wall-frame buildings. First, it evaluates the efficacy of Special Boundary Elements (SBEs) in shear walls, whose seismic performance enhancement remains uncertain despite recent (i.e., after the 2010 earthquake) mandates in Chile. Second, it investigates the relevance of explicit inclusion of slabs in 3D nonlinear models (in dual wall-frame buildings slabs are often not modeled for computational expediency). Various analytical models of a representative 16-story dual wall-frame archetype building are meticulously evaluated using Perform3D. Different vertical heights of the SBEs (ranging from 0 to 5 stories) and different values of the effective flexural stiffness of the slabs (ranging from 0 to 100% of the gross cross-section stiffness) are considered. Subduction ground motions representative of the Chilean seismicity are selected and scaled based on detailed seismic hazard analyses. Evaluation metrics include collapse fragility functions and 50-year collapse probabilities. Inelastic deformations in the shear walls are thoroughly analyzed. It was found that the effective flexural stiffness of the slabs has a non-negligible influence on the analytical collapse probability, and that SBEs do not provide ductility but they do reduce the collapse probability
Impact of Amerindian ancestry on clinical outcomes in Crohn’s disease and ulcerative colitis in a Latino population
No full textResearch in Inflammatory Bowel Disease (IBD) assessing the genetic structure and its association with IBD phenotypes is needed, especially in IBD-underrepresented populations such as the South American IBD population. Aim. We examine the correlation between Amerindian ancestry and IBD phenotypes within a South American cohort and investigate the association between previously identified IBD risk variants and phenotypes. We assessed the ancestral structure (IBD = 291, Controls = 51) to examine the association between Amerindian ancestry (AMR) and IBD variables. Additionally, we analyzed the influence of known IBD genetic risk factors on disease outcomes. We used Chi-square and Fisher’s tests to analyze the relationship between phenotypes and ancestry proportions, calculating odds ratios (OR) and confidence intervals (CI). Logistic regression examined genetic variants associations with IBD outcomes, and classification models for predicting prolonged remission were developed using decision tree and random forest techniques. The median distribution of global ancestry was 58% European, 39% Amerindian, and 3% African. There were no significant differences in IBD risk based on ancestry proportion between cases and controls. In Ulcerative colitis (UC), patients with a high Amerindian Ancestry Proportion (HAAP) were significantly linked to increased chances of resective surgery (OR = 4.27, CI = 1.41–12.94, p = 0.01), pouch formation (OR = 7.47, CI = 1.86–30.1, p = 0.003), and IBD reactivation during COVID-19 infection (OR = 5.16, CI = 1.61–6.53, p = 0.005). Whereas, in the Crohn’s Disease (CD) group, the median Amerindian ancestry proportion was lower in the group with perianal disease (33.5% versus 39.5%, P value = 0.03). CD patients with High Amerindian Ancestry proportion had lower risk for surgery (OR = 0.17, CI = 0.03–0.83, P value = 0.02). Our study highlights the impact of Amerindian ancestry on IBD phenotypes, suggesting a role for genetic and ancestral factors in disease phenotype. Further investigation is needed to unravel the underlying mechanisms driving these associations.UKRI Medical Research CouncilANI
Relationships between executive funtions and linguistic skills in Spanish-speaking children with and without developmental language disorder
No full textTesis (Doctor of Psychology)--Pontificia Universidad Católica de Chile, 2024Developmental language disorder (DLD) is a condition that impacts the development of different language skills, mainly vocabulary and morphosyntax. In addition, DLD has often been associated with difficulties in executive functions (EFs). It has also been suggested that difficulties in EF could be linked to language deficits in these children. Based on this, a broader perspective suggests that the development of language and EFs may be interconnected in children with and without DLD. However, the specific patterns in which each EF is associated with language skills remain unclear. For this reason, three studies were proposed. The first study aims to describe the performance of several EFs in children with DLD compared to an age-matched typical development (TD) group. Then, two central studies explore the EFs-language relationship in children with and without DLD. Study 2 investigates the relationship between several EF measures and vocabulary knowledge (size and depth). Study 3 evaluates the relationship between several EFs and morphosyntactic skills (comprehension and production). For the three studies, 204 children aged 6 to 8 years were examined: 105 with DLD and 99 with typical development (TD). In Study 1, multiple regression models were performed with group (DLD and TD) as the independent variable and each EF, one at a time, as the dependent variable. For studies 2 and 3, multiple regression models were performed including the EFs as predictors and language skills (vocabulary in study 2, and morphosyntax in study 3) as outcome variables. All models were adjusted to the participant's age and nonverbal intelligence. Complementarily, in studies 2 and 3, after identifying the EFs associated with each language skill (vocabulary and morphosyntax), path analyses were conducted to explore models of relationships between variables. The results of Study 1 indicate that DLD children have significantly lower performance in interference control, response inhibition, and verbal working memory compared to TD children. There was no difference in nonverbal working memory and cognitive flexibility. Results from studies 2 and 3 indicate that verbal working memory and cognitive flexibility are significantly associated with vocabulary knowledge and morphosyntactic skills in children with DLD. In children with TD, there is less reliance on EFs for language processing. These studies suggest that EFs play a crucial role in language development in children with DLD, highlighting the importance of including EF activities in intervention programs for this population
The R-transform as power map and its generalizations to higher degree
No full textWe give iterative constructions for irreducible polynomials over Fq of degree n⋅tr for all r≥0, starting from irreducible polynomials of degree n. The iterative constructions correspond modulo fractional linear transformations to compositions with power functions xt. The R-transform introduced by Cohen is recovered as a particular case corresponding to x2, hence we obtain a generalization of Cohen's R-transform (t=2) to arbitrary degrees t≥2. Important properties like self-reciprocity and invariance of roots under certain automorphisms are deduced from invariance under multiplication by appropriate roots of unity. Extending to quadratic extensions of Fq we recover and generalize a recursive construction of Panario, Reis and Wang.Science Academy-BAGEPBoğaziçi University; Folio: 15B06SUP2ANID FONDECYT; Folio: 1211858CONICYT-MEC; Folio: 8013006
Endogenous Galectin-8 protects against Th17 infiltration and fibrosis following acute kidney injury
No full textBackground Acute kidney injury (AKI) is a serious clinical condition characterized by a rapid decline in renal function, often progressing to chronic kidney disease (CKD) and fibrosis. The endogenous mechanisms influencing kidney injury resolution or maladaptive repair remain poorly understood. Galectin‑8 (Gal‑8), a tandem‑repeat β‑galactosidebinding lectin, plays a role in epithelial cell proliferation, epithelial‑mesenchymal transition, and immune regulation, all of which are critical in AKI outcomes. While exogenous Gal‑8 administration has shown renoprotective effects, its endogenous role in kidney injury progression and resolution remains unclear. Methods To investigate the endogenous role of Gal‑8 in AKI, we compared the responses of Gal‑8 knockout (Gal8‑KO; Lgals8−/− bearing a β‑gal cassette under the Lgals8 gene promoter) and wild‑type (Lgals8+/+) mice in a nephrotoxic folic acid (FA)‑induced AKI model. Renal Gal‑8 expression was assessed by β‑galactosidase staining, lectin‑marker colocalization, and RT‑qPCR. Renal function, structure, and immune responses were evaluated at the acute (day 2) and fibrotic (day 14) phases of injury. Plasma creatinine levels were measured to assess renal function, while histological analyses evaluated tubular damage, renal inflammation, and extracellular matrix deposition. Flow cytometry was performed to characterize the immune response, focusing on pro‑inflammatory T cells. Results Galectin‑8 was predominantly expressed in the renal cortex, localizing to tubules, glomeruli, and blood vessels, with its levels decreasing by half following AKI. Both Lgals8+/+ and Lgals8−/− mice exhibited similar renal function and structure impairments during the acute phase, though Lgals8+/+ mice showed slightly worse damage. By the fibrotic phase, Lgals8−/− mice exhibited more pronounced cortical damage and fibrosis, characterized by increased type I and III collagen deposition and enhanced Th17 cell infiltration, while myofibroblast activation remained comparable to that of Lgals8+/+ mice. Conclusions Endogenous Gal‑8 does not significantly protect the kidney during the acute phase and is dispensable for cell proliferation and death in response to AKI. However, it is crucial in preventing maladaptive repair by regulating
Search for supersymmetry in final states with missing transverse momentum and charm-tagged jets using 139 fb−1 of proton-proton collisions at Vs = 13 TeV with the ATLAS detector
No full textThe paper presents a search for supersymmetric particles produced in proton-proton collisions at s = 13 TeV and decaying into final states with missing transverse momentum and jets originating from charm quarks. The data were taken with the ATLAS detector at the Large Hadron Collider at CERN from 2015 to 2018 and correspond to an integrated luminosity of 139 fb−1. No significant excess of events over the expected Standard Model background expectation is observed in optimized signal regions, and limits are set on the production cross-sections of the supersymmetric particles. Pair production of charm squarks or top squarks, each decaying into a charm quark and the lightest supersymmetric particle χ ~ 1 0 , is excluded at 95% confidence level for squarks with masses up to 900 GeV for scenarios where the mass of χ ~ 1 0 is below 50 GeV. Additionally, the production of leptoquarks with masses up to 900 GeV is excluded for the scenario where up-type leptoquarks decay into a charm quark and a neutrino. Model-independent limits on cross-sections and event yields for processes beyond the Standard Model are also reported
The R-transform as power map and its generalizations to higher degree
No full textWe give iterative constructions for irreducible polynomials over Fq of degree n⋅tr for all r≥0, starting from irreducible polynomials of degree n. The iterative constructions correspond modulo fractional linear transformations to compositions with power functions xt. The R-transform introduced by Cohen is recovered as a particular case corresponding to x2, hence we obtain a generalization of Cohen's R-transform (t=2) to arbitrary degrees t≥2. Important properties like self-reciprocity and invariance of roots under certain automorphisms are deduced from invariance under multiplication by appropriate roots of unity. Extending to quadratic extensions of Fq we recover and generalize a recursive construction of Panario, Reis and Wang.Science Academy-BAGEPBoğaziçi University; Folio: 15B06SUP2ANID FONDECYT; Folio: 1211858CONICYT-MEC; Folio: 8013006
Competency assessment in initial teacher training in physical education: a systematic review
No full textIntroducción: La evaluación de competencias en la formación de docentes de educación física es fundamental para desarrollar habilidades esenciales en el ejercicio profesional. Estas competencias incluyen conocimientos técnicos, habilidades prácticas y un enfoque integral que abarca dimensiones pedagógicas y éticas. La diversidad en las competencias refleja la pluralidad de enfoques adoptados por las instituciones de educación superior, que priorizan diferentes áreas para responder a las demandas del sistema escolar actual. Objetivo: Analizar los tipos de competencias evaluadas durante la formación de profesores de educación física. Método: Se realizó una revisión sistemática siguiendo la declaración PRISMA, abarcando artículos en las bases de datos WoS, Scopus, Sportdiscus y ERIC, hasta julio de 2024. Los estudios se seleccionaron en función de criterios específicos de inclusión. Resultados: De un total de 820 estudios identificados, 38 cumplieron con los criterios de inclusión y fueron clasificados en siete categorías principales: a) Competencias comunicativas; b) Competencias tecnológicas y digitales; c) Competencias didácticas y pedagógicas; d) Competencias personales y socioemocionales; e) Competencias en inclusión y adaptación a contextos diversos; f) Competencias de identidad profesional y ética; y g) Competencias evaluativas y de retroalimentación. Conclusión: La priorización de competencias pedagógicas y socioemocionales en la formación de docentes de educación física fomenta un enfoque integral que genera una formación equilibrada y adaptable, promoviendo un desempeño eficaz en contextos educativos diversos