Universidad de Magallanes
Not a member yet
1947 research outputs found
Sort by
Efectos de un programa de telerehabilitación sobre la funcionalidad en personas mayores
No full textObjective: To determine the effects of a telerehabilitation (TR) program on the level of functional independence and the number of falls in older people attending a day care center. Materials and method: 14 older people (x̄ = 74 years), submitted to a kinesitherapy / physiotherapy / physical therapy (PT) program through telerehabilitation for a period of 12 weeks. The control group received educational intervention through a physical activity booklet which they had to develop independently, with weekly telephone supervision, while the experimental group received 15 kinesitherapy / physiotherapy / physical therapy sessions via video calls through WhatsAppTM application. Both groups were evaluated pre and post intervention with the Barthel index scale (BI) and the number of falls using the comprehensive geriatric assessment (CGA). Results: The experimental group increased the Barthel index scale score (↑3,6) while the control group decreased this score (↓6,9). Both groups decreased the number of falls, without differences between groups. When comparing both groups, the elderly who underwent a kinesitherapy / physiotherapy / physical therapy program through telerehabilitation showed significantly greater improvements in Barthel index scale than the control group (p <0.05). Conclusion: Older people who participated in a kinesitherapy / physiotherapy / physical therapy program through telerehabilitation presented a higher level of functional independence compared to participants in the intervention with a phone call-guided physical activity booklet, which suggests a telerehabilitation programs as an alternative therapeutics to improve the level of independence in older people. Keywords: Elderly; Telerehabilitation; Independent Living; Accidental Falls; Clinical Tria
Filling ecological gaps in Chilean Central Patagonia: Patterns of biodiversity and distribution of sublittoral benthic invertebrates from the Katalalixar National Reserve waters (∼48°S)
No full textKnowledge about the composition, diversity, and geographic distribution of marine species is important for successful conservation planning in the future. The ecological and zoogeographic patterns of benthic communities in Central Patagonia have been scarcely studied, due to the remoteness of the area combined with harsh weather conditions. During the past years, five scientific expeditions were executed in order to study the biodiversity, ecological, and biogeographical patterns of benthic invertebrates in the Katalalixar National Reserve (KNR) waters, Central Patagonia (similar to 48 degrees S). Our analyses comprised images from 26 video transects using a remotely operated vehicle, completed with biological sampling at four stations by means of SCUBA diving, covering a bathymetric range from 10 to 220 m depth. Stations covered the entire longitudinal range of the KNR, from inner channels to the Pacific Ocean. A total of 187 benthic invertebrate taxa were identified as OTUs (operational taxonomic units), with mollusks being the most conspicuous taxonomic group (18.7%), followed by sponges, echinoderms (16.6% each), and arthropods (14.4%). A higher OTU richness (42 to 51 OTUs) was observed in the central and western parts of the KNR waters. Analyses of the beta-diversity indicated a similar level of species turnover between shallow, intermediate, and deep strata, as well as an important turnover between different locations. Dissimilitudes in the assemblage structure of invertebrates were explained mainly by changes in substrate types and longitude. Most of the species (49%) found in the KNR waters showed a wide latitudinal distribution range along the Eastern South Pacific Ocean (ESP) and the Chilean Patagonia of fjords and channels (CPFC) (similar to 18 degrees S and similar to 56 degrees S), whereas 9.4% of the species have a wide distribution range between the CPFC and south of the Antarctic polar front (SAPF) (similar to 42 degrees S and similar to 65 degrees S). Since only 16.7% of the species identified in the KNR are distributed exclusively in CPFC waters, it may be considered a transition area for marine invertebrates. It is distributed between northern ESP and SAPF. Knowledge of species composition and distribution patterns along spatial and environmental gradients is essential for any sustainable management, monitoring, and future conservation plans to protect the fragile and diverse marine ecosystems of Chilean Patagonia
Presencia de Corythucha ciliata (Say, 1832) y Corythucha arcuata (Say, 1832) (Hemiptera: Tingidae) en Argentina, ampliación de la distribución de C. ciliata en Chile e inclusión de una nueva sinonimia específica
No full textResumen Se cita por primera vez para la Argentina a Corythucha ciliata (Say) (Hemiptera: Heteroptera: Tingidae), que se alimenta primariamente del plátano o sicómoro (Platanus x hispanica Mill. ex Münchh), así como también se extiende su distribución en Chile. Adicionalmente, se registra por primera vez en territorio argentino a Corythucha arcuata (Say), que se alimenta del roble común (Quercus robur L.), y se establece su conespecificidad con Corythucha bonaerensis Montemayor nov. sin. Se dan también nuevos registros distribucionales y de planta hospedante para Corythucha argentinensis Monte, y se discute la taxonomía de las especies argentinas del género. Se proveen imágenes de ejemplares recolectados y se dan sus caracteres diagnósticos. Se comenta brevemente la importancia de la aparición de estas especies en el país
The Subantarctic Rayadito (Aphrastura subantarctica), a new bird species on the southernmost islands of the Americas
No full textWe describe a new taxon of terrestrial bird of the genus Aphrastura (rayaditos) inhabiting the Diego Ramirez Archipelago, the southernmost point of the American continent. This archipelago is geographically isolated and lacks terrestrial mammalian predators as well as woody plants, providing a contrasted habitat to the forests inhabited by the other two Aphrastura spp. Individuals of Diego Ramirez differ morphologically from Aphrastura spinicauda, the taxonomic group they were originally attributed to, by their larger beaks, longer tarsi, shorter tails, and larger body mass. These birds move at shorter distances from ground level, and instead of nesting in cavities in trees, they breed in cavities in the ground, reflecting different life-histories. Both taxa are genetically differentiated based on mitochondrial and autosomal markers, with no evidence of current gene flow. Although further research is required to define how far divergence has proceeded along the speciation continuum, we propose A. subantarctica as a new taxonomic unit, given its unique morphological, genetic, and behavioral attributes in a non-forested habitat. The discovery of this endemic passerine highlights the need to monitor and conserve this still-pristine archipelago devoid of exotic species, which is now protected by the recently created Diego Ramirez Islands-Drake Passage Marine Park
Kinetics of ABE fermentation considering the different phenotypes present in a batch culture of Clostridium beijerinckii NCIMB-8052
No full textBackground: In solvent-producing Clostridium species, several physiological conditions and morphological forms can be observed during batch ABE fermentation. Currently, the contribution made by each condition or form to the production of acids and solvents is not clear. Flow cytometry and fluorescence microscopy have been used to analyze the presence of different morphological and physiological conditions for Clostridium species; however, there are few studies to quantify their contribution to fermentation kinetics. Results: Morphological changes of the batch cultures of Clostridium beijerinckii NCIMB-8052 were followed by flow cytometry and epifluorescence microscopy. Three cell types were identified, and the percentage of each one was estimated along the culture, showing that they are present throughout the culture and its population distribution was in agreement with the kinetics of growth and acids and solvents production. Yields for the global population and for each subpopulation were estimated. The values of the yield for butanol and acetone based on the fraction of solventogenic cells were 2.5 times the values of the parameters obtained for the whole biomass, while those for acetic and butyric acids based on the acidogenic cell type was 1.5 times. Conclusions: Quantitative analysis of the subpopulations by flow cytometry allows the calculation of the yields related to specific cell types, isolating the contribution of each subpopulation to the production of acids and solvents. How to cite: Paredes I, Quintero J, Guerrero K, et al. Kinetics of ABE fermentation considering the different phenotypes present in a batch culture of Clostridium beijerinckii NCIMB-8052. Electron J Biotechnol 2022;56. https://doi.org/10.1016/j.ejbt.2021.12.002 (c) 2022 Pontificia Universidad Catolica de Valparaiso. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Immune checkpoint inhibitors. A breakthrough in cancer therapy La inhibicion de los puntos de control inmunologico, una terapia en evolucion: remembranza del Premio Nobel de Medicina 2018
No full textProfessors James P. Allison and Tasuku Honjo were awarded with the 2018 Nobel Prize in Medicine for their contributions in cancer immunotherapy. The latter is a breakthrough in cancer therapy, aimed to overcome tumor- induced immunosuppression, leading to the reactivation of the immune system against cancer cells. Under physiological conditions, the CTLA-4 and PD-1 proteins expressed on T-cells and discovered by the awarded scientists, lead to immune tolerance. Cancer cells exploit these control points to enhance the inhibition of T-cells. The expression of PD ligands (PD-L1) in tumor cells and CTLA-4 ligands in antigen presenting cells, which bind the PD-1 receptor and CTLA-4 respectively, block anti-tumor immunity. This situation led to a biotechnological race focused on the development of effective antibodies able to "turn-on" the immune system cheated by the tumor. Anti-CTLA-4 and anti-PD-1 antibodies improve life-expectancy in cancer patients. In this review, we perform an historical overview of Professors Allison and Honjo contribution, as well as the immunological basis of this new and powerful therapeutic strategy, highlighting the clinical benefits of such intervention
Feeding Ecology of Odontaster validus under Different Environmental Conditions in the West Antarctic Peninsula
No full textSimple Summary Even though researchers have previously examined the diet of O. validus, the feeding ecology of this species of sea star is still poorly understood. To address this issue, we used a multifaceted approach to investigate the diet of O. validus from three systems with marked environmental differences of the northern Antarctic Peninsula. The results showed a significant divergence of O. validus delta N-15-delta C-13 values among regions, suggesting a habitat-specific foraging behavior and confirming the ability of this species to switch resource utilization across differing habitat compositions, which may be a key survival response in the face of environmental change. To study how Odontaster validus can influence the spatial structure of Antarctic benthic communities and how they respond to disturbance, it is necessary to assess potential dietary shifts in different habitats. We investigated the diets of O. validus from Maxwell Bay and South Bay in the West Antarctic Peninsula. A multifaceted approach was applied including in situ observations of cardiac stomach everted contents, isotopic niche, and trophic diversity metrics. Results confirm the flexible foraging strategy of this species under markedly different environmental conditions, suggesting plasticity in resource use. The data also showed evidence of isotopic niche expansion, high delta N-15 values, and Nacella concinna as a common food item for individuals inhabiting a site with low seasonal sea ice (Ardley Cove), which could have significant ecological implications such as new trophic linkages within the Antarctic benthic community. These results highlight the importance of considering trophic changes of key species to their environment as multiple ecological factors can vary as a function of climatic conditions
A 32-day long fieldwork in Antarctica improves heat tolerance during physical exercise
No full textAbstract We evaluated the influence of a 32-day camping in Antarctica on physical performance and exercise-induced thermoregulatory responses. In Brazil, before and after the Antarctic camping, the volunteers performed an incremental exercise at temperate conditions and, two days later, an exercise heat stress protocol (45-min running at 60% of maximum aerobic speed, at 31°C and 60% of relative humidity). In Antarctica, core temperature was assessed on a day of fieldwork, and average values higher than 38.5°C were reported. At pre- and post-Antarctica, physiological (whole-body and local sweat rate, number of active sweat glands, sweat gland output, core and skin temperatures) and perceptual (thermal comfort and sensation) variables were measured. The Antarctic camping improved the participants' performance and induced heat-related adaptations, as evidenced by sweat redistribution (lower in the chest but higher in grouped data from the forehead, forearm, and thigh) and reduced skin temperatures in the forehead and chest during the exercise heat stress protocol. Notwithstanding the acclimatization, the participants did not report differences of the thermal sensation and comfort. In conclusion, staying in an Antarctic camp for 32 days improved physical performance and elicited physiological adaptations to heat due to the physical exertion-induced hyperthermia in the field
Admissible Orders on Fuzzy Numbers
No full textFrom the more than two hundred partial orders for fuzzy numbers proposed in the literature, only a few are total. In this article, we introduce the notion of admissible order for fuzzy numbers equipped with a partial order, i.e., a total order which refines the partial order. In particular, it is given special attention to the partial order proposed by Klir and Yuan in 1995. Moreover, we propose a method to construct admissible orders on fuzzy numbers in terms of linear orders defined for intervals considering a strictly increasing upper dense sequence, proving that this order is admissible for a given partial order. Finally, we use admissible orders to ranking the path costs in fuzzy weighted graphs
Experiencia Para El Olvido O Una Oportunidad De Innovación En La Educación. Estudio De La Experiencia De Docentes Y Educadores De La Región De Magallanes Y Antártica Chilena En Medio De La Crisis Del Covid-19
No full textLa Pandemia por Covid 19 trajo consigo profundos cambios para el sistema educativo global y nacional. Las Universidades debieron adaptarse a una nueva forma de hacer docencia, principalmente, modificando sus prácticas de enseñanza-aprendizaje. Este libro responde a un desafío trazado por la Red Universitaria Estatal de Formación Inicial de Profesores con el objetivo reunir en una publicación participativa interuniversitaria, experiencias, estudios y discusiones teóricas en torno a la educación en tiempos de pandemia en Chile. Las temáticas incluyen prácticas pedagógicas en el contexto de pandemia; didácticas, metodologías de enseñanza-aprendizaje y estrategias de evaluación en modalidad online; estrategias de flexibilización, integración y priorización curricular en tiempos de Covid, entre otras