Universidad de Magallanes
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Tailored Investments Needed to Support Weather, Water, Ice, and Climate Services in the Polar Regions
No full textThe Polar Prediction Project (PPP), one of the flagship programs of the World Meteorological Organization's (WMO) World Weather Research Programme (WWRP), has come to an end after a decade of intensive and coordinated international observing, modeling, verification, user engagement, and education activities. While PPP facilitated many advancements in modeling and forecasting, critical investment is now required to turn prediction science into salient environmental services for the polar regions. In this commentary, the members of the Societal and Economic Research and Applications task team of PPP, a group of social scientists and service delivery specialists, identify a number of insights and lessons that are critical for the implementation of the follow-up program Polar Coupled Analysis and Prediction for Services (PCAPS). We argue that in order to raise the societal value of polar environmental services, we need to better understand the diversity of highly specific user contexts; to tailor the actionability of weather, water, ice, and climate (WWIC) service development in the polar regions through inclusive transdisciplinary approaches to coproduction; to assess the societal impact of improved environmental services in the polar regions; and to invest and provide dedicated funding for involving the social sciences in research and tailoring processes across all the polar regions
Resolving the paradox of conflicting glacial chronologies: Reconstructing the pattern of deglaciation of the Magellan cordilleran ice dome (53-54°S) during the last glacial - interglacial transition
No full textRaised shorelines and associated lacustrine sediments in the central Estrecho de Magallanes (Strait of Magellan) have been interpreted as products of cordilleran glaciers impounding a large proglacial lake and preventing drainage to the South Pacific and Southern Ocean during the Late glacial between c. 15.0 and 12.0 cal ka BP. However, a growing body of glacial geological evidence points towards an earlier retreat of the Magellan cordilleran ice dome, insufficient to dam lakes at that time. We critically re-evaluate the extant evidence for the c. 15.0-12.0 cal ka BP lake, here named 'Lago Kawesqar', and provide further sedimentological and chronological evidence for its existence. We also provide new cosmogenic surface nuclide dating of erratic and bedrock samples collected from extensive field campaigns that confirm the rapid and widespread retreat of the Magellan ice fields to the inner fjords of the Fuegian archipelago by c. 16.0 ka. To resolve the apparent paradox between these two lines of evidence we propose that glacial isostatic adjustment led to a topographic barrier to lake drainage rather than an ice dam. We use Glacial Isostatic Adjustment modelling to demonstrate that rapid isostatic recovery following the early deglaciation after c. 17.0 cal ka BP likely led to elevation of the present shallow south-western coastal margin of the Fuegian archipelago. Final drainage of Lago Kawesqar was probably caused by neotectonic subsidence of the same margin along the boundary of the South American - Scotia tectonic plates at c. 12.0 cal ka BP
Didactic strategy of linear algebra with collaborative learning in mathematics pedagogical training
No full textThis article details the design and implementation of a didactic intervention strategy aimed at enhancing the pedagogical skills of mathematics education students in the teaching of linear algebra. Given the challenges students often face in grasping abstract mathematical concepts, the intervention leverages the Anthropological Theory of Didactics and Collaborative Learning as its theoretical framework. The phases of the intervention's execution in the classroom, along with the key elements for successful implementation, are thoroughly outlined. The results indicate significant improvements in academic performance in the units' covering determinants, matrices, and systems of linear equations, while challenges persist in the unit on vector spaces. In terms of task genres, students showed proficiency in defining and calculating, although there was a lower level of mastery in demonstrating. The study concludes that, despite a general unfamiliarity with autonomous learning, the future educators were able to become active and effective contributors to their own mathematical knowledge construction through collaborative group work
A generalization of the Moore and Yang integral and interval probability density functions
No full textBased on an extension of Riemann sums, Moore and Yang have defined an integral notion for the context of continuous inclusion monotonic interval functions in which the limits of integration are real numbers. This integral notion generalizes the usual one for real-valued functions based on Riemann sums. In this paper we extend this approach by considering intervals as limits of integration and abolishing the inclusion monotonic restriction of the integrable interval functions. Also, such a new integration notion is used to define interval probability density functions and use it in interval probability distribution functions
When ice and sea are not barriers for flies: First report of Trichocera maculipennis (Diptera) in South America
No full textDuring the 2022/2023 austral winter, large swarms of Trichocera (Saltrichocera) maculipennis Meigen, 1818 (Diptera: Trichoceridae), were observed around house roofs in Puerto Williams (Navarino Island, southern Chile, 54 degrees S). In January 2023, the presence of this species was also confirmed in Punta Arenas (53 degrees S), with specimens collected within the Chilean Antarctic Institute warehouse facilities. Trichocera maculipennis is native to the Holarctic region and became established on King George Island (South Shetland Islands, Maritime Antarctic) over 15 years ago. However, the species has not previously been reported from South America. Taxonomic and molecular identification techniques were used to confirm the identity of the new specimens obtained from Navarino Island and Punta Arenas. Preliminary observations of the fly's habitat preferences and swarming behaviour in Puerto Williams are provided, as well as comparisons in wing morphometrics between flies from Puerto Williams and King George Island. The fly's extensive distribution and high abundance in Puerto Williams are consistent with human-facilitated introduction and several years' establishment. These findings emphasise the importance of implementing robust management strategies and biosecurity measures, particularly during transportation between logistical hubs in southern South America and the remote areas of the Cape Horn Biosphere Reserve and Antarctica
Eccentric-induced delayed-onset muscle soreness impairs cardiac autonomic activity in adolescent athletes: a pre-experimental study El dolor muscular de aparición tardía inducido por contracción excéntrica afecta negativamente la actividad autonómica cardíaca en adolescentes atletas: un estudio pre-experimental
No full textObjective: To investigate the impact of eccentric-induced delayed-onset muscle soreness (DOMS) on cardiac autonomic activity in adolescent athletes. Methods: A pre-experimental one-group pre-test/post-test design was carried out on fifteen competitive adolescent athletes, and the effect of DOMS on cardiac autonomic activity was assessed while controlling for body composition and anxious state/trait factors. An eccentric exercise protocol was applied to the elbow's flexor muscles to induce DOMS. Then, heart rate variability was compared before and two days after DOMS induction under resting and resisted movement conditions of the painful limb, using a t-test for paired samples. The body composition and the State-Trait Anxiety Inventory (STAI) were also measured. Results: The analysis revealed a significant effect of DOMS on autonomic response in time domain measures of root mean square of successive differences (RMSSD) (MD = -5.58, 95%CI[-9.36, -1.8], t(14) = -3.2, p = 0.007) and standard deviation of normal-to-normal intervals (SDNN) (MD = -9.43, 95%CI[-15.47, -3.39], t(13) = -3.4, p = 0.005), as well as on sympathetic nervous system (SNS) autonomic indices (MD = 0.68, 95%CI[0.07, 1.29], t(14) = 2.4, p = 0.031) and Stress index (SI) (MD = 2.72, 95%CI[0.67, 4.77], t(14) = 2.8, p = 0.013) under exercise conditions. Conclusions: DOMS changes cardiac autonomic activity compared to control conditions during mechanically evoked pain but not at rest. This study highlights the importance of considering the presence of DOMS when HRV is used in adolescent athletes for training, clinical, or research purposes
Artemia enrichment as modulator of gene expression patterns of Enteroctopus megalocyathus paralarvae at pre-settlement stage
No full textEnteroctopus megalocyathus, the Patagonian red octopus, is the only octopus species for which a complete pro-duction cycle in captivity has been accomplished in Chile. The rearing of E. megalocyathus paralarvae from hatching to the settlement of juveniles lasts 90 days and it represents the bottleneck in the culture of this species. The paralarval stages from 1 to 60 days after hatching (DAH) are fed on enriched Artemia while, when pre -settlement behavior appears, from 60 DAH onwards, the feeding protocol is a mixed diet of enriched Artemia and juvenile marine crabs. Marine crustaceans represent a suitable diet to improve E. megalocyathus paralarvae survival, complementing the enriched Artemia to feed the pre-settling paralarvae. To determine the effect of Artemia enrichment on the response of E. megalocyathus at the pre-settling paralarval stage, paralarvae were fed two mixed diets containing juvenile marine crabs (Petrolisthes spp.) and differing only in Artemia enrichment: enriched (complete diet, CD), or unenriched (limited diet, LD). After 30 days of feeding trial, samples consisting of whole paralarvae were collected for transcriptomic analysis using high-quality total RNA to generate six mRNA libraries (two treatments x three biological replicates). A total of 270 genes were differentially expressed between paralarvae fed LD and those fed CD. When classifying the cellular processes in which the genes of LD and CD paralarvae differed significantly, it was observed that the downregulated/upregulated gene ratio was 2/1 in genes related to membrane organization and neuron differentiation. The genes of paralarvae fed a LD for which upregulation was equal to or >20 times compared with those fed a CD were related with increased rearrangement of tissues, molecular transport, energy production, improvement of sensory organs, cellular processes, transcription, and protein catabolic processes. The downregulated genes in paralarvae fed a LD were involved with reduced DNA repair and mRNA replication and elongation, molecular transport, cellular protein modification, cellular component organization, inflammatory cytokines, and biosynthetic processes. It was concluded that removing enrichment from Artemia, even under co-feeding with marine crustaceans, results in notable changes in the transcription that, while not generating a significant detriment to growth in 30 days of experimentation, could affect subsequent growth phases
Two lenses for exploring relationships between seabirds and fishers: Unveiling reciprocal contributions
No full text1. Reciprocal relationships between fishers and marine life have been documented in Indigenous fishing contexts, but there are few case studies that describe the mechanisms of such relationships, and even fewer that explore other contexts, such as that of artisanal fishers in Latin American countries. 2. We studied the artisanal hake fishery in the sub-Antarctic channels of Chilean Patagonia, a global hotspot for albatross and petrel diversity. We aimed to uncover nature's contributions to hake fishers and, reciprocally, the potential fishers' contributions to marine life with a particular emphasis on seabirds. We adopted a bifocal observational strategy. From a human perspective, ethnographic methods (e.g., semi-structured interviews) are analysed with Nature's Contributions to People and reciprocal contribution frameworks. From the seabirds' view, we assessed offal consumption through experimental and observational methods. We randomly threw offal items into the sea and observed the seabird responses (whether they consumed offal). 3. Hake fishers' relationships with the marine environment are multidimensional, particularly with seabirds. Based on fishers' perceptions, we identified four key contributions of seabirds to humans: they serve as value indicators of fishing distribution and concentration areas, offer companionship and recreation during fishing activities, enhance scenic emotionality through the presence of albatrosses and assist in the function of sea cleaning. In reciprocal contributions, artisanal fishers viewed hake offal as a beneficial food source for the seabirds, especially the liver. Fishers described that fishing in the right way can reduce bycatch and effort. 4. The fishers' main contribution to seabirds is through offering them the offal of hake catches. We observed that seabirds consumed hake liver 99% of the time, while they consumed stomach less frequently (24%). We identified that southern giant petrels and black-browed albatrosses consumed more liver, while kelp gulls ate more stomach. The liver comprises 51.6% fat, essential for high trophic level marine predators such as black-browed albatrosses. 5. Adopting reciprocal contributions and NCP served as a catalyst for understanding fishers' positive actions but also is a promoter to research multiple views of nature-human relationships in fishing settings. Values of nature, like reciprocity, could enrich ecosystem-based management strategies
Citizen commitment development through undergraduate internships at the UNPADE-Magallanes
No full textFavoring the relationship with the community and organizations by strengthening the cultural, economic, and social heritage of the Region of Magallanes is part of the strategic guidelines of the University of Magallanes. To do this, the Construction Engineering undergraduate program takes up the challenge of giving its students the values that will guide them to coexist, question, learn, and position themselves in a critical and constructive perspective in social and work life, legitimizing the dignity of people. The institutional generic competence "Social Responsibility and Citizen Commitment" (RS_CC, in Spanish) is included in the Construction Engineering undergraduate curriculum. Second-year students carried out their internship at UNPADE (National Union of Parents and Friends of People with Mental Disabilities). This organization is open to the community and meets the needs of all people with disability who require an educational workspace. This social internship is part of the Engineering training plan, whose goal is to make students aware of their role, directly related to improving people's quality of life in a sustainable way, and to understand that the projected solutions are systemic and dynamic, responding to the constant evolution of society. This initiative is a pioneering activity in the professional training of construction engineers so that they know their social role as professionals from their formative stage. This activity was an opportunity for the development of engineers aiming at their personal growth through theoretical and practical training with a sense of reality, showing elements considered significant for a learning design based on social practices. This research was conducted, using student self-assessment rubrics and individual practice reports, showing that the students reached the RS_CC competence, by using PBL (project-based learning) in the subject "Practica I"
While clearing the forests: The social-ecological memory of trees in the Anthropocene
No full textThe Anthropocene concept raises awareness of human-induced planetary changes but is criticized for being 'too global'. We examined the social-ecological memory that emerges from people-tree relationships in South American temperate territories, Chile. We integrated dendrochronology (analysis of tree rings of 35 memorial trees; 17 species) with dendrography (participant observation complemented with semi-structured and go-along interviews with 14 interviewees; six women, eight men). We found that assemblages of people-tree relationships reflect marked historical changes in the territory, associated with the historical clearing of forests, which may be imprinted in both tree growth rings and in the social meanings and practices associated with memorial trees. In devastated territories, practices of tree care emphasize interconnectedness, multispecies collaborations, and the blurring of boundaries between humans and other-than-humans. We discuss some of the interdisciplinary and relational insights of our study, which may prove valuable for future research, political agendas, and educational programs in South America and beyond