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Fragmentos de un motivo: cortometraje
No full textProyecto para la obtención del tÃtulo de realizador cinematográfico.Este cortometraje busca ser un material psicoeducativo sobre el suicidio. Explora el trauma infantil de Rodrigo, que se convierte en el desencadenante para tomar la decisión de quitarse la vida a los 26 años. Iniciando un viaje entre la vida y la muerte, sumergiéndose en diversos recuerdos de su existencia. En este trayecto, descubre en la amistad una razón para intentar seguir adelante
Is physical fitness related with in-game physical performance? A case study through local positioning system in professional basketball players
No full textThe purpose of this study was to investigate the relationship between physical fitness and external load determined by local positioning system (LPS) in a simulated basketball game. Fourteen professional male basketball players performed a lane agility drill, 20-m maximal sprint speed, countermovement jump (CMJ), drop jump, and repeated sprint tests. Player movements during games (two games of 4 x 7 min) were measured using a portable WIMUPRO LPS and six ultra-wideband antennas. Distance covered, and distance covered in different speed zones, accelerations, and decelerations were recorded. The results obtained showed significant relationship between (a) distance at high decelerations (>-2.0 m s(-2)) and 20-m maximal sprint speed (r = 0.669, p = 0.049); (b) 20-m maximal sprint speed and maximal speed in simulated games (r = 0.576, p = 0.031); (c) CMJ height and sprint distance (>24.1 km h(-1)) covered in simulated games (r = 0.772, p = 0.001); and (d) high decelerations and 20-m maximal sprint speed (r = 0.669, p = 0.049) and best time in the RSA test (r = -0.731, p = 0.039). Coaches and strength and conditioning coaches must adjust their training to optimize speed and jumping ability, as they are reflected in physical performance in-game. Players who reach higher speeds (i.e. RSA(best) and 20-m sprint time) and CMJ height in field tests may be affected by greater deceleration load in specific training and competition (eccentric contraction). Since hamstring muscles suffer great strain during deceleration, they are more prone to injury, thus these players may require a specific training program to decrease performance losses and risk of injury
EXPERIENCES ON THE SENATE. REFLECTIONS FOR THE LATIN AMERICAN DEBATE
No full textEl presente trabajo busca discutir sobre funcionamiento de los senados en América Latina. Las diferentes secciones del Foro de debate mezclan, de manera original, una reflexión teórica con recopilación de datos a nivel comparado y de caso. Las dos primeras secciones del trabajo analizan, primero, la evolución de los bicameralismos y unicameralismos en el mundo y luego los senados en América Latina. Las siguientes colaboraciones son dos análisis de caso de paÃses con composiciones bicamerales: Chile, Argentina y Brasil. La última contribución es teórica y tiene como objetivo entender el concepto de autoridad en un órgano con actores ambiciosos y de manejo formal e informal. Estos artÃculos fueron realizados gracias al proyecto FONDECYT Regular 1211297 y la Iniciativa Milenio NCS2022_046
The windstorm of transgression and singularity in the narratives of Pedro Juan Gutiérrez and Fernando Vallejo
No full textEl presente artÃculo, tiene como propósito analizar el contenido polÃtico y transgresivo de las narrativas de Pedro Juan Gutiérrez y Fernando Vallejo. El método que se emplea es el diálogo con la crÃtica precedente, la operacionalización de conceptos filosóficos y el comentario textual e intertextual de textos literarios; para ello se efectúa un examen textual desde la perspectiva filosófica, que incluye los aportes de Foucault y Onfray. Los resultados visibilizan los desplieges singulares de forma y fondo presentes en un corpus representativo de textos escogidos de estos escritores latinoamericanos del siglo XX. De ese estudio decantan mecanismos y trasfondos de poder y transgresión que conectan la ficción con la realidad regional de los escritores abordados. Se concluye que estas narrativas expresan la singularidad nómade y la transgresión en la voz de sus narradores, quienes contradicen el principio de sumisión
Prey selection along a predators' body size gradient evidences the role of different trait-based mechanisms in food web organization
No full textAn increase in prey richness, prey size and predator trophic position with predator body size has been consistently reported as prime features of food web organization. These trends have been explained by non-exclusive mechanisms. First, the increase in energy demand with body size determines that larger predators must reduce prey selectivity for achieving the required number of resources, being consumption relationships independent of prey traits. Second, when consumption is restricted by gape limitation, small predators are constrained to select among small prey. However, this selection weakens over large predators, which progressively consume more and larger prey. Finally, the optimal foraging mechanism predicts that larger predators optimize their diet by selecting only large prey with high energy reward. Each one of these mechanisms can individually explain the increase in prey richness, prey size and predator trophic position with predator body size but their relative importance or the direct evidence for their combined role was seldom considered. Here we use the community assembly by trait selection (CATS) theory for evaluating the support for each one of these mechanisms based on the prey selection patterns that they predict. We analyzed how prey body size and trophic guild determine prey selection by predators of increasing body size in a killifish guild from a temporary pond system. Results support the combination of the three mechanisms to explain the structural trends in our food web, although their strength is contingent on prey trophic group. Overall, high energy prey are preferred by larger predators, and small predators select small prey of all trophic status. However, large predators prefer large primary producers and avoid large carnivorous prey, probably because of the inherent risk of consuming other carnivorous. Our study provides a mechanistic understanding of how predator traits determine the selection of prey traits affecting food web assembly.This research was funded by Comision Academica de Posgrado (https://www.posgrados.udelar.edu.uy/cap.php), grant numbers BDDX_2019_1#49295789 and BFPD_2022_1#49295789 and CSIC_Iniciacion_2019_ID_36 to EO; Agencia Nacional de Investigacion y Desarrollo/Fondo Nacional de Desarrollo Cientifico y Tecnologico (https://www.anid.cl/), grant number 1231321 to RRJ; and Agencia Nacional de Investigacion e Innovacion (https://www.anii.org.uy/) from the Fondo Clemente Estable, grant number 2014104763 and CSIC-grupos (ID 657725) to MA. This study was performed in the framework of the European Commission, PONDERFUL Horizon 2020 project (H2020-LC-CLA-2019-2). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Senescent Schwann cells induced by aging and chronic denervation impair axonal regeneration following peripheral nerve injury
No full textFollowing peripheral nerve injury, successful axonal growth and functional recovery require Schwann cell (SC) reprogramming into a reparative phenotype, a process dependent upon c-Jun transcription factor activation. Unfortunately, axonal regeneration is greatly impaired in aged organisms and following chronic denervation, which can lead to poor clinical outcomes. While diminished c-Jun expression in SCs has been associated with regenerative failure, it is unclear whether the inability to maintain a repair state is associated with the transition into an axonal growth inhibition phenotype. We here find that reparative SCs transition into a senescent phenotype, characterized by diminished c-Jun expression and secretion of inhibitory factors for axonal regeneration in aging and chronic denervation. In both conditions, the elimination of senescent SCs by systemic senolytic drug treatment or genetic targeting improved nerve regeneration and functional recovery, increased c-Jun expression and decreased nerve inflammation. This work provides the first characterization of senescent SCs and their influence on axonal regeneration in aging and chronic denervation, opening new avenues for enhancing regeneration and functional recovery after peripheral nerve injuries.P01 AG017242/AG/NIA NIH HHS/United States; R01 AG051729/AG/NIA NIH HHS/United States; S10 OD028654/OD/NIH HHS/United States; U01 AG060906/AG/NIA NIH HHS/United States
Sequential epidemic-like spread between agglomerates of self-propelled agents in one dimension
No full textMotile organisms can form stable agglomerates such as cities or colonies. In the outbreak of a highly contagious disease, the control of large-scale epidemic spread depends on factors like the number and size of agglomerates, travel rate between them, and disease recovery rate. While the emergence of agglomerates permits early interventions, it also explains longer real epidemics. In this work, we study the spread of susceptible-infected-recovered (SIR) epidemics (or any sort of information exchange by contact) in one-dimensional spatially structured systems. By working in one dimension, we establish a necessary foundation for future investigation in higher dimensions and mimic micro-organisms in narrow channels. We employ a model of self-propelled particles which spontaneously form multiple clusters. For a lower rate of stochastic reorientation, particles have a higher tendency to agglomerate and therefore the clusters become larger and less numerous. We examine the time evolution averaged over many epidemics and how it is affected by the existence of clusters through the eventual recovery of infected particles before reaching new clusters. New terms appear in the SIR differential equations in the last epidemic stages. We show how the final number of ever-infected individuals depends nontrivially on single-individual parameters. In particular, the number of ever-infected individuals first increases with the reorientation rate since particles escape sooner from clusters and spread the disease. For higher reorientation rate, travel between clusters becomes too diffusive and the clusters too small, decreasing the number of ever-infected individuals
Socioeconomic position and executive functioning from childhood to young adulthood: Evidence from Santiago, Chile
No full textBackground: Optimizing cognitive development through early adulthood has implications for population health. This study aims to understand how socioeconomic position (SEP) across development relates to executive functioning. We evaluate three frameworks in life-course epidemiology - the sensitive period, accumulation, and social mobility hypotheses.Methods: Participants were young adults from Santiago, Chile who were studied from 6 months to 21 years. Family SEP was measured at ages 1 y, 10 y, and 16 y with the modified Graffar Index. Executive functioning was assessed at ages 16 y and 21 y by the Trail Making Test Part B (Trails B). Analyses estimating 16 y and 21 y executive function involved 581 and 469 participants, respectively. Trails B scores were modeled as a function of SEP at 1 y, 10 y, and 16 y, as the total accumulation of disadvantage, and as change in SEP between 1 y and 10 y and between 10 y and 16 y.Results: Participants were low-to middle-income in infancy and, on average, experienced upwards mobility across childhood. Half of participants (58%) improved Trails B scores from 16 y and 21 y. Most (68%) experi-enced upward social mobility between infancy and 16 y. When examined independently, worse SEP measured at 10 y and 16 y related to worse (longer time to complete) Trails B scores at Age 21 but did not relate to the other outcomes. After mutual adjustment as a test of the sensitivity hypothesis, no SEP measure was independently related to any outcome. Testing the accumulation hypothesis, cumulative low SEP was associated with worse cognitive performance at 21 y (beta symbolscript 3.6, p symbolscript 0.04).Results for the social mobility hypothesis showed no relation to cognitive scores or to change in cognitive scores. Comparing all hypotheses, SEP at 16 y explained the most variability in executive functioning at 21 y, providing support for the sensitive period hypothesis.Conclusions: Results indicate that experiencing cumulatively low socioeconomic position from infancy to adolescence can have a negative impact on cognitive functioning in young adulthood. Findings also provide evidence in support of adolescence as a key developmental period during which SEP can most strongly impact cognitive functioning.This work was supported by the Eunice Kennedy Shriver National Institute of Child Health & Human Development [grant number R01 HD033487-15] ; the National Institute on Drug Abuse [grant number R01 DA021181-05] ; the National Heart, Lung and, Blood Institute [grant number T32 HL079891-11] ; and ANID-MILENIO-NCS2021_013. The authors acknowledge the participants and their families for making this study possible and Marcela Castillo, lead psychologist responsible for participant recruitment and evaluation since the infancy study who passed away in 2015
Salmonella Type III Secretion Effector SrfJ: A Glucosylceramidase Affecting the Lipidome and the Transcriptome of Mammalian Host Cells
No full textType III secretion systems are found in many Gram-negative pathogens and symbionts of animals and plants. Salmonella enterica has two type III secretion systems associated with virulence, one involved in the invasion of host cells and another involved in maintaining an appropriate intracellular niche. SrfJ is an effector of the second type III secretion system. In this study, we explored the biochemical function of SrfJ and the consequences for mammalian host cells of the expression of this S. enterica effector. Our experiments suggest that SrfJ is a glucosylceramidase that alters the lipidome and the transcriptome of host cells, both when expressed alone in epithelial cells and when translocated into macrophages in the context of Salmonella infection. We were able to identify seventeen lipids with higher levels and six lipids with lower levels in the presence of SrfJ. Analysis of the forty-five genes, the expression of which is significantly altered by SrfJ with a fold-change threshold of two, suggests that this effector may be involved in protecting Salmonella from host immune defenses.This research was funded by grant PID2019-106132RB-I00 funded by MCIN/AEI/10.13039/501100011033. It was also funded by Fondo Europeo de Desarrollo Regional (FEDER) y Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades de la Junta de Andalucia: grant P20_00576; Universidad de Sevilla, Fondo Europeo de Desarrollo Regional (FEDER) y Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades de la Junta de Andalucia: grant US-1380805; Plan de Recuperacion, Transformacion y Resiliencia > (via a Maria Zambrano research fellowship, to RB)
Implementation of a virtual telehealth course for Chilean older adults and health students
No full textBackground: Aging increases the vulnerability to diseases and environmental changes such as the COVID-19 pandemic. Telehealth and tele-education are vital to prevent the deleterious effects of prolonged confinement, and to train the community, and constantly rotating medical students and health professionals. Aim: To assess the perception and impact of an online course about healthy aging aimed at the community and health care professionals. Material and Methods: An open online one-day course to promote healthy aging was carried out. A cross-sectional online survey about the course was answered by 386 attendants and a knowledge test was applied to 114 people. Results: Seventy-five percent of respondents attended the course synchronously. Of these, 79% were women, 20% were older people and 53% were caregivers of an older person. All respondents acquired new knowledge and were willing to participate again. The frequency of interest about self-care is three times greater than about caring for another person, In an older person, the interest is 101 more times about self-care than caring for another person. Ninety five percent of respondents felt more active and 84% felt more accompanied. Conclusions: The course facilitated access to information on the promotion of active and healthy aging in the community with a favorable perception and a positive impact. The coverage for older people with a digital gap should be improved