Universidad de Magallanes
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Maternal sensitivity in early childhood and body mass index in adolescence: A population-based study on the role of self-regulation as a mediator
No full textMaternal sensitivity has been implicated in various aspects of child health and development, including overweight. However, long-term effects, the role of paternal sensitivity and the explanatory pathways are unclear. This study examined whether maternal sensitivity in early childhood is prospectively associated with adolescent body mass index and whether children's self-regulation mediates this relation. Data from 540 children and their mothers were available from a large cohort study in the Netherlands. Maternal sensitivity was assessed at child ages 1, 3, and at 4 years paternal sensitivity was also included. Children's self-regulation skills were observed at age 3, eating behaviour was assessed at 10 years, and child BMI was measured at 13 years. Longitudinal structural equation modelling was applied. The cross-sectional association between maternal sensitivity and child self-regulation was significant, while lower levels of self-regulation and higher levels of food responsiveness and restrained eating predicted a higher child BMI at 13 years. Furthermore, a direct association of paternal sensitivity at 4 years with BMI at 13 years was found, but only in girls. Maternal sensitivity was not directly associated with child BMI after adjusting for covariates. Our findings showed the importance of self-regulation in the early years for subsequent weight development. Nevertheless, as self-regulation could not explain the relationship between parenting and child weight, research should focus on the contribution of other contextual factors, such as feeding styles and the social environment, to this relationship
Hand rehabilitation based on the RobHand exoskeleton in stroke patients: A case series study
No full textIntroduction: The RobHand (Robot for Hand Rehabilitation) is a robotic neuromotor rehabilitation exoskeleton that assists in performing flexion and extension movements of the fingers. The present case study assesses changes in manual function and hand muscle strength of four selected stroke patients after completion of an established training program. In addition, safety and user satisfaction are also evaluated. Methods: The training program consisted of 16 sessions; two 60-minute training sessions per week for eight consecutive weeks. During each session, patients moved through six consecutive rehabilitation stages using the RobHand. Manual function assessments were applied before and after the training program and safety tests were carried out after each session. A user evaluation questionnaire was filled out after each patient completed the program. Results: The safety test showed the absence of significant adverse events, such as skin lesions or fatigue. An average score of 4 out of 5 was obtained on the Quebec User Evaluation of Satisfaction with Assistive Technology 2.0 Scale. Users were very satisfied with the weight, comfort, and quality of professional services. A Kruskal-Wallis test revealed that there were not statistically significant changes in the manual function tests between the beginning and the end of the training program. Discussion: It can be concluded that the RobHand is a safe rehabilitation technology and users were satisfied with the system. No statistically significant differences in manual function were found. This could be due to the high influence of the stroke stage on motor recovery since the study was performed with chronic patients. Hence, future studies should evaluate the rehabilitation effectiveness of the repetitive use of the RobHand exoskeleton on subacute patients
Mild Traumatic Brain Injury Induces Mitochondrial Calcium Overload and Triggers the Upregulation of NCLX in the Hippocampus
No full textTraumatic brain injury (TBI) is brain damage due to external forces. Mild TBI (mTBI) is the most common form of TBI, and repeated mTBI is a risk factor for developing neurodegenerative diseases. Several mechanisms of neuronal damage have been described in the cortex and hippocampus, including mitochondrial dysfunction. However, up until now, there have been no studies evaluating mitochondrial calcium dynamics. Here, we evaluated mitochondrial calcium dynamics in an mTBI model in mice using isolated hippocampal mitochondria for biochemical studies. We observed that 24 h after mTBI, there is a decrease in mitochondrial membrane potential and an increase in basal matrix calcium levels. These findings are accompanied by increased mitochondrial calcium efflux and no changes in mitochondrial calcium uptake. We also observed an increase in NCLX protein levels and calcium retention capacity. Our results suggest that under mTBI, the hippocampal cells respond by incrementing NCLX levels to restore mitochondrial function
Episodic Binge-like Ethanol Reduces Skeletal Muscle Strength Associated with Atrophy, Fibrosis, and Inflammation in Young Rats
No full textBinge Drinking (BD) corresponds to episodes of ingestion of large amounts of ethanol in a short time, typically <= 2 h. BD occurs across all populations, but young and sports-related people are especially vulnerable. However, the short- and long-term effects of episodic BD on skeletal muscle function have been poorly explored. Young rats were randomized into two groups: control and episodic Binge-Like ethanol protocol (BEP) (ethanol 3 g/kg IP, 4 episodes of 2-days ON-2-days OFF paradigm). Muscle function was evaluated two weeks after the last BEP episode. We found that rats exposed to BEP presented decreased muscle strength and increased fatigability, compared with control animals. Furthermore, we observed that skeletal muscle from rats exposed to BEP presented muscle atrophy, evidenced by reduced fiber size and increased expression of atrophic genes. We also observed that BEP induced fibrotic and inflammation markers, accompanied by mislocalization of nNOS mu and high levels of protein nitration. Our findings suggest that episodic binge-like ethanol exposure alters contractile capacity and increases fatigue by mechanisms involving atrophy, fibrosis, and inflammation, which remain for at least two weeks after ethanol clearance. These pathological features are common to several neuromuscular diseases and might affect muscle performance and health in the long term
VILLA CEREPEC-CHIGUAYANTE. COOPERATIVISMO E HABITAÇÃO COLETIVA NA ÁREA DA GRANDE CONCEPCIÓN
No full textRESUMEN El Área Metropolitana de Concepción (AMC) evidencia las huellas de la industria en su desarrollo urbano. Bajo el alero de las industrias estatales y de sus trabajadores, desde la segunda mitad del siglo XX se desarrollaron conjuntos habitacionales distanciados de las plantas industriales, que propusieron nuevos modos de desarrollo urbano para su época y lugar. Un caso relevante es el de la Cooperativa de Empleados Refinería de Petróleo Concepción (CEREPEC), en Chiguayante. Este trabajo registra parte de la evolución urbana de esta comuna, a través del análisis del conjunto habitacional, que se vio materializado por trabajadores de la Empresa Nacional del Petróleo (ENAP) bajo el modelo cooperativista. Los resultados evidencian tanto en el aporte fundacional a la construcción del espacio urbano de la "calle Manantiales", como la forma en que el cooperativismo se materializó en el diseño urbano y el proyecto arquitectónico del conjunto CEREPEC. Destaca la relación empresa-trabajador-caja de ahorros, donde el trabajador asume el liderazgo y la empresa apoya la gestión, en un modelo muy distante del paternalismo industrial que construye con lógicas diferentes nuevas fracciones de ciudad. Se trata de un modelo de relevancia por cuanto los procesos participativos se constituyen en una demanda de gran actualidad, los que involucran las dinámicas de construcción y transformación de viviendas y barrios
Efectos de la radiación UV-B en la morfología, el contenido de compuestos absorbentes UV-B y pigmentos fotosintéticos de Plantago lanceolata y Rheum rhabarbarum
No full textIn recent decades the fluence of ultraviolet-B (UV-B) radiation striking the ground has increased as a consequence of ozone depletion at southern latitudes. This phenomenon has sparked much interest in unravelling how plants acclimate to this condition. UV-B radiation triggers several responses that affect plant physiology, morphology and biochemistry. In this study, the effects of supplemental UV-B radiation on plant architecture, UV-B absorbing compounds and photosynthetic pigments were analyzed in two cosmopolitan species. A different range of responsiveness was found in the morphological parameters (leaf area, length and width; plant height) of species. The effects on photosynthetic pigment content and the UV-B absorbing compounds were studied through absorbance measurements. The obtained data showed that only carotenoids increased in irradiated plants of R. rhabarabarum. Likewise, an increase in the UV-B absorbing compounds content was found in irradiated plants from the same species. This effect may be regarded as a chemical protection against the damaging effects of light in photosynthesis and against oxidative cell damage. UV-B radiation induced photomorphogenic responses. In fact, all the morphological parameters of P. lanceolata were increased. The clear increase shown in leaf size and plant height suggest that cell division and stem elongation and/or differentiation processes are stimulated by UV-B radiation. These changes can be seen as an eustress effect and may indicate that plants are physiologically adapted to this level of UV-B radiation
“Me echaron de mi casa, empecé a trabajar en la calle”: interseccionalidad y apartheid ocupacional en el trabajo sexual. Un estudio de caso
No full textResumen Introducción Las mujeres que se han dedicado al trabajo sexual han sido una comunidad estigmatizada, marginada y alienada socialmente. Particularmente, en el caso de las mujeres trans la situación ha sido peor, enfrentando mayores porcentajes de violencia. Objetivo Analizar la historia de vida de una mujer trans que se desempeña en el trabajo sexual, a partir de un análisis interseccional y ocupacional. Método Empleamos un estudio cualitativo basado en la técnica de investigación Historia de Vida, considerando elementos de la entrevista narrativa ocupacional. Resultados Desde su historia, podemos ver que hay elementos que han interseccionado a lo largo de su vida, tales como los dominios: estructural, disciplinar, hegemónico e interpersonal. Sus elecciones ocupacionales han estado fuertemente influenciadas por su contexto dentro de un apartheid ocupacional, buscando la generación de espacios de resistencia y agencia frente a las diferentes adversidades. Conclusiones Estas situaciones precarizan sus condiciones de vida y ponen en alerta las influencias de los sistemas económicos, políticos, heteronormados, entre otros, en la determinación de la vida de las personas
Environmental evolution of western Tierra del Fuego (-54°S) since ice-free conditions and its zonal/hemispheric implications
No full textBy virtue of its position adjacent to the Drake Passage, Tierra del Fuego in South America allows examining the vegetation and environmental history of the southernmost continental landmass outside Antarctica, and the evolution of the Southern Westerly Winds-Southern Ocean (SWW-SO) coupled system since the Last Glacial Maximum (LGM). For that purpose, we studied sediment cores from Lago Charquito, a small closed-basin lake in central-west Tierra del Fuego with a continuous lacustrine record since-17.3 ka. Ice-free conditions at the site imply a-70 km retreat of the Bahia Inutil glacier lobe from its LGM position during a-800-year interval, a trend that continued until its disappearance-100 km upstream from L. Charquito,-800 years later. Our palynological data show an open landscape dominated by cold-tolerant shrubs and herbs between-17.3-12.9 ka, with increases in precipitation of SWW origin at-16.3 ka,-14.7 ka, between-8.7-7.6 ka, and after-6.8 ka. Warming at-12.9 ka initiated an abrupt afforestation trend that stalled during the early Holocene (-12-8.7 ka) owing to a precipitation decline and wildfires, and later resumed in response to invigorated SWW. We hypothesize that sparse Nothofagus tree populations inhabited the periphery of the Patagonian Ice Sheet (PIS) during the LGM and migrated toward the Andes contemporaneous with glacier recession as temperature rose during the Last Glacial Termination (T1). We posit that besides establishing topographic and climatic barriers for land biota, the PIS enabled the connectivity of cold-tolerant hygrophilous plant populations along a humid fringe adjacent to its land-based perimeter, despite the presumably dry conditions downwind from the eastern PIS margin. Our results suggest that southward shifts or expansion of the SWW toward or beyond Tierra del Fuego enhanced upwelling and ventilation of deep waters in the SO, northward shifts or weakening had the opposite effect. We observe that the time evolution of atmospheric CO2 concentrations, high-latitude air and sea-surface temperatures, and sea level during T1 fall short in explaining the timing and abruptness of the Bahia Inutil glacier lobe collapse, and quite possibly multiple other glacier lobes from the PIS
Gender knowledge, territorialising the rhizome, and playing with creative methods
No full textConstructing academic knowledge in and from the global South is riddled with negotiations of oneself, our collectivities, and the demands of productivity. In our activism in and outside academia, gender knowledge emerges like grass: unpredictable, collective, abundant, messy. In policy and higher education, the field is limited by the credentials of expertise with all the restrictions, pressures, and limitations of higher education and its demands for publication. Gender studies is currently a contested field, facing attacks from across the political spectrum that question its rigour, ethics, and very nature. In this context, rooted in our concern for how we construct gender knowledge and the continued colonial consequences of academia, we reflect on our own negotiation processes and offer our methodologies of creativity and play as a way to evade the limits of expertise. Inspired by Deleuze and Guattari's concept of rhizomes as well as MacLure's call to wonder, we examine the intersections of our experiences and our positionalities in and with the academic spaces we inhabit, to discuss methodologies in knowledge construction. We look at how these methodologies allow us to map contradictions and tensions in the construction of knowledge between the arboreal forms of what is considered knowledge and the other that is possible, born from where we have been cut, the phantom members of the decolonial ghost
Chemical Characterization of Atmospheric Aerosols in Monte Fenton, Punta Arenas, Chilean Southern Patagonia
No full textThis work addresses the chemical characterization of atmospheric aerosols and precipitation in the period from May to November 2019 at Monte Fenton (53.16&DEG; S, 71.05&DEG; W, 612 m.a.s.l.), 9 km west of Punta Arenas, to study the contribution and distribution of emission sources and chemical enrichment. The main ions (Ca2+, Cl-, K+, Mg2+, Na+, NH4+, NO3- and SO42-) were studied using ion chromatography, and trace elements (Al, Br, Ca, Cl, Cr, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Se, Si, Ti, V and Zn) using energy dispersive X-ray fluorescence. Ions concentration ranged from 5.0 x 10(-1) to 2.9 x 10(4) mg/m(3) for Ca2+ and Cl-, respectively; whilst the concentration of elements varied between 8.8 x 10(-11) and 2.1 x 10(-2) mg/m(3), for crZn (crustal Zn) and Fe, respectively. The electrical conductivity (EC, mean = 32.5μS/cm) and the pH (mean = 6.8), showed the atmosphere of the study site was relatively neutral compared to the standard pH for rain (or snow) without contamination (pH = 5.6), and presented relatively low levels of conductivity compared to the EC standards for distilled water (0.5 to 3μS/cm) and seawater (30,000 to 60,000μS/cm). The main contribution to aerosols in the atmosphere of Monte Fenton came from marine and lithospheric sources, followed by local anthropogenic sources such as burning firewood and/or urban waste for heating production, etc., that led to the enrichment of aerosols with high Fe, K, Mn and V content. The results of this study contribute to filling a gap in knowledge of the chemistry of atmospheric aerosols in Southern Patagonia