Hospital Clínico de la Universidad Católica
Pontificia Universidad Católica de Chile: Repositorio UCNot a member yet
70241 research outputs found
Sort by
Traits drive responses of aphidophagous coccinellid communities to landscape complexity
No full textCoccinellids are important biocontrol agents which are threatened by agricultural intensification and landscape change. Their responses to the landscape are inconsistent which may be due to a taxonomic focus of studies that misses the traits that drive the differences in species responses to the landscape.In this study, we investigated how coccinellids in alfalfa respond to environmental variables in terms of their traits. We examined five traits: body size, activity period, habitat specialization, spatial ubiquity and dispersal habits, and analysed how single and multiple traits (syndromes) are affected by local variables (aphid density), and landscape compositional (diversity of land uses) and configurational heterogeneity (edge density), at two spatial scales (500 and 1500 m).The community-weighted mean of all traits, except body size, was affected by landscape heterogeneity, mostly at the smaller spatial scale. Coccinellid communities break into two groups of trait syndromes in their response to landscape heterogeneity. Smaller species, uncommon in alfalfa, mostly native, were negatively associated with compositional and configurational heterogeneity at both spatial scales, while the remaining species were associated with increased landscape heterogeneity. This latter group of species splits into two groups at the smaller spatial scale, composed by large exotic and natives, distributed along a gradient of landscape configurational heterogeneity.The response of ladybeetles to landscape composition and configuration depends more on their traits than on their origin (native vs. exotics). These responses should be considered when designing policies for agricultural landscape management, depending on the conservation aims
Conjunto de datos: Data raw responses from REDCap
No full textThe present study aims to describe and discuss the voting experiences of people with disabilities in Chile during two of the national elections which took place in 2021. This study explores whether people with disabilities in Chile know and use assisted voting, the main legal tool at their disposal to facilitate their right to vote. The results suggest that despite the existence of legal provisions and special protocols created to facilitate voting for people with disabilities, there are still multiple barriers that hinder their interaction with the Chilean electoral system. While some barriers are related to non-compliance of provisions and protocols, pointing to implementation gaps, other barriers are related to the design of the electoral system, suggesting the need to push for its reform to create a more inclusive electoral system.202
Evaluation of the relationship between intercostal muscle oxygenation measured by near‑infrared spectroscopy and exercise capacity in group E COPD patients
No full textOpening the Methodological Black Box in Science and Technology Studies of the Future(s). Shadows and Proposals
No full textScience and Technology Studies (STS) emerged from a focus on the methods of “natural” scientists. Over the past decade, there has been an increasing concern with the field’s methodologies. Two enduring points of contention are the performative effects of methods and the need to further appraise STS methodologies by comparing them to others to understand why they work—or fail to work. We contribute to this ongoing discussion by focusing on a prolific area of research where performativity has been a key concern, but methodological reflection is limited: the study of futures. Within this context, we ask how STS scholars methodologically render the future into something researchable. By constructing a comprehensive database of publications and a methodological appraisal instrument, we demonstrate that most studies in the field fail to meet minimum reporting criteria. Arguments often overreach their declared objectives or are inadequately justified in their methods. Moreover, research on the future currently fails to acknowledge the various types of inference required to build arguments about the meanings, actions, and materialities related to the future. To advance STS, we propose practical strategies and guidelines to address these issues when working with both verbal and observational data. In general, the recommendation is to (1) improve methodological reporting, (2) explicitly identify the inferences being made, and (3) secure them through data triangulation, comparative designs, proper interview structures, and by avoiding subject biase
Conjunto de datos : Encuesta Nacional Bicentenario UC 2021
No full textLa Encuesta Bicentenario UC es un proyecto de la Pontificia Universidad Católica de Chile, coordinado por el Centro de Políticas Públicas UC y en elaboración conjunta con la Facultad de Ciencias Sociales UC. El diseño muestral y trabajo de campo es responsabilidad de la Dirección de Estudios Sociales (DESUC).202
Which Cultural Dimensions Predict Variations in Emotional Conformity? An Extension of Vishkin et al. (2023) Across 28 Nations
No full textDespite being a classic social psychology topic, cultural variability in conformity has only been examined systematically in the last few decades. Vishkin et al. reported evidence that conformity of experienced emotions and of valued emotions is stronger in individualistic cultures. We tested the replicability of this finding using data from 28 nations (N = 6,168), incorporating two further relevant cultural predictors of cultural differences: flexibility-monumentalism and tightness-looseness. Contrasting effects regarding valence were found for conformity of experienced emotions and of valued emotions. Conformity of experienced positive emotions and of valued negative emotions was predicted by individualism, monumentalism, and looseness. The results are discussed in terms of the distinction between injunctive and descriptive norms and cultural variations in the salience of positive and negative emotions. Using additional indicators of cultural difference yields a fuller understanding of these effects than that provided by the contrast between individualism and collectivism. The use of deviation scores provides a useful operationalization of variations in conformity
Role of lysosomal integral membrane protein type 2 (LIMP2) in neuronal endolysosomal trafficking and its relevance in Gaucher disease type 2
No full textTesis (Doctor of Biological Sciences)--Pontificia Universidad Católica de Chile, 2025TESIS EMBARGADA POR LA ALUMNA HASTA EL 22 DE ABRIL DE 2026Background: Gaucher disease type 2 (GD2) is a neuronopathic acute lysosomal storage disease (LSD) caused by mutations in the GBA1 gene, which lead to the loss of β-Glucocerebrosidase (β-GC) lysosomal activity. This enzymatic deficiency triggers the accumulation of glucosylceramide (GluCer) in the lysosomes, mainly in macrophages and neurons. In GD2 neurons, synaptic alterations, neuroinflammation, and neuronal loss have been described, yet the underlying mechanisms remain unclear. Recently, an altered distribution of LIMP2+ structures that preceded neuroinflammation and neuronal loss was reported in GD2 models, suggesting the role of LIMP2 in pathology. LIMP2 is a lysosomal integral membrane protein and the only β-GC transporter described. However, current literature has pointed out the pivotal role of LIMP2 in endolysosomal biogenesis and trafficking. We wonder if LIMP2 alterations in GD2 could impact endolysosomal homeostasis and if these defects could be associated with synaptic dysfunction in GD2 pharmacological models. Aim: To characterize LIMP2 alterations and their impact on endolysosomal trafficking and their association with modifications in synaptic parameters in GD2. Results: GD2 models, including mice and hippocampal neurons treated with CβE, showed increased LIMP2 protein levels compared to controls. Interestingly, these models also exhibited aberrant LIMP2+ tubular structures that were not found in control models or other LSDs. We identify these structures as endolysosomal compartments based on their colocalization with LAMP1, LAMTOR4, and SirLyso. Furthermore, these structures colocalize with VTi1B and likely with LC3 and clathrin. These proteins, along with LIMP2, are involved in autophagy and lysophagy. Due to tubular morphology and the association with these markers, we propose that these aberrant endolysosomal compartments may arise from defects in lysosomal reformation. Besides, GD2 hippocampal neurons displayed an altered endolysosomal dynamics with a global decrease of fusion, fission, and kiss & run events. Alterations in endolysosomal structures and dynamics occurred in parallel with changes in post-synaptic parameters, such as downregulation of NR2B, PSD95, and HOMER protein levels in hippocampal neurons and a decrease in the number of post-synaptic densities (PSD) in the cortex of CβE-treated mice. Conclusions: We report the presence of aberrant endolysosomal compartments that are unique to the GD2 phenotype. Moreover, these structures may be closely related to defects in lysosomal reformation, either from autophagy or lysophagy. Furthermore, an alteration of endolysosomal dynamics could be associated with the origin of these structures and could impact other cellular processes, such as cellular trafficking. Together with the changes in endolysosomal homeostasis, the GD2 context is characterized by changes in post-synaptic components. Given the essential role of the endolysosomal system in synaptic function and maintenance, our findings highlight that there could exist a potential link between endolysosomal alterations and synaptic dysfunction. A deeper understanding of this relationship is essential to uncover pathological mechanisms involved in the GD2 context.FondefCorfoFundación Copec U
Unconventional monetary policy and household heterogeneity: evidence from QE shocks
No full textTesis (Magíster en Economía)--Pontificia Universidad Católica de Chile, 2024This paper examines the heterogeneous effects of Large-Scale Asset Purchases (LSAP) on household consumption, assets, and liabilities across different income cohorts using a Smooth Local Projections (SLP) approach. We find that high-income households experience an immediate and significant increase in consumption, while low-income families initially reduce consumption but show a delayed increase starting six quarters after the shock.We identify two primary channels through which LSAP shocks operate. First, a valuation effect on financial assets benefits high-income households with substantial wealth and sufficient liquidity to respond to the shock. Second, a real activity channel, where decreasing unemployment from heightened economic activity contributes to increased consumption among low-income households after a year and a half.Additionally, we propose that heightened prepayment and refinancing activity may explain the initial decline in consumption among low-income households.These findings highlight the differentiated impacts of LSAP shocks on various household groups and offer insights into the mechanisms driving these responses, drawing comparisons to conventional monetary policy shocks