Universidad de Magallanes
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THE LAST THOUSAND YEARS OF CHILOÉ: TRICOLOR, A SETTLEMENT ON THE PACIFIC COAST
No full textNear the last millennium, an important change in cultural trajectories at Chiloe Island is marked by the appearance of horticultural and pottery traditions. Based on various lines of evidence, we can sustain that, for the Late Holocene, marine hunter-gatherers-fishermen from the northern Patagonian archipelago used and consumed wild and domesticated plants. The Tricolor archaeological site, located on the central Pacific coast of Chiloe, along with the various studies carried out regarding ceramic manufacture, organic use residues, together with a diverse set of radiocarbon dates (charcoals, organic residues, TL), are relevant to begin to fill the gaps in the archaeological record of the last centuries up to European contact. With this we contribute to the discussion about the subsistence processes, changes and cultural continuities that occurred in the area during the last centuries of pre-Hispanic human occupation
"Listen to us": small-scale farmers' understandings of social-ecological changes and their drivers in Important Agricultural Heritage Systems
No full textCurrent social-ecological changes affect territories and people's livelihoods worldwide. Many of these changes have detrimental effects on small-scale agricultural systems, with concomitant negative consequences on global and local food security and sovereignty. The objectives of this study were to explore (i) local knowledge on social-ecological changes and (ii) the perceived drivers of those changes occurring in a mountainscape and an islandscape in two Important Agricultural Heritage Systems of southern South America, both located within a Global Biodiversity Hotspot. This was done by conducting in-depth semi-structured interviews with local campesinos, whose livelihoods are based on the use and management of agrosilvopastoral systems. We found that local communities experience a wide range of globally and locally induced social-ecological changes acting in their territories. Campesinos mentioned 79 different observations of social-ecological changes and identified drivers for 77% of them. Changes in the atmospheric system, specifically regarding changes in precipitation, drought, and temperatures, were commonly observed by campesinos in both sites. Participants also observed complex interrelations between these changes and the drivers influencing them, climatic drivers being the most important. Even though general changes in climatic patterns were identified as drivers of changes by campesinos, other situated changes derived from the site's biophysical, social, and economic conditions were also important. Our results highlight the importance of considering local knowledge to understand social-ecological changes and to support the development and implementation of public policies that promote contextualized adaptation measures to global changes that affect local livelihoods
Notes on distributions of Heteroptera (Insecta: Hemiptera) in northern Patagonia and central region of Argentina
No full textThe present knowledge of Heteroptera in northern Patagonia and central region of Argentina is widely scattered and admittedly very incomplete. In the present work we provide a checklist of 17 species from northern Patagonia and the central region of Argentina, including 16 new records for provinces and one new record for the country
Committing to the Antarctic: values, ecological beliefs, and social identity in national perception
No full textThe objective of this study is to analyse the role of a perceived value that may result from identification with the Antarctic region the identity that results from association with the Chilean claim to that territory, and adherence to various ecological beliefs that may bear on a perception of responsibility in the care and protection of Antarctica, by inhabitants of southern Chilean Patagonia. Three general population studies (n1=218), (n2=401), (n3=260) measured what were termed Antarctic values, Antarctic Social Identity (ASI), ecological beliefs, and perceived responsibility for Antarctic care and protection. The first study showed the importance of social identification as a mediating variable between the attributed Antarctic value and the perception of responsibility, showing that the identity variable played a fundamental role in the phenomenon of perceived responsibility. The second study compares three cities that formally share the 'Antarctic social identity' label (a sense of belonging to the group of cities linked to the Antarctic). This study reveals that, despite sharing this social category, the orientation related to custodial behaviour towards Antarctica is also linked to other socio-identity variables. Here we refer to all the psychological and social variables involved in the process that leads to feeling part of one social identity; that is, identifying with a group of people with whom one shares, for example, the place where one lives. The third study compares two generations of adults ('young' and 'mature') and confirms that the older group shows a pattern of social responsibility that considers identity variables more profoundly. These results are discussed within the context of the importance of understanding the role of these variables in attitudes towards the Antarctic region at a time when, from both political and environmental perspectives, opportunities arise for inhabitants living close to this territory to reconsider their roles
Natural Products from Chilean and Antarctic Marine Fungi and Their Biomedical Relevance
No full textFungi are a prolific source of bioactive molecules. During the past few decades, many bioactive natural products have been isolated from marine fungi. Chile is a country with 6435 Km of coastline along the Pacific Ocean and houses a unique fungal biodiversity. This review summarizes the field of fungal natural products isolated from Antarctic and Chilean marine environments and their biological activities
Enhanced Peripheral Chemoreflex Drive Is Associated with Cardiorespiratory Disorders in Mice with Coronary Heart Disease
No full textCoronary heart disease (CHD) is a prevalent cardiovascular disease characterized by coronary artery blood flow reductions caused by lipid deposition and oxidation within the coronary arteries. Dyslipidemia is associated with local tissue damage by oxidative stress/inflammation and carotid bodies (CB) peripheral chemoreceptors are heavily modulated by both reactive oxygen species and pro-inflammatory molecules (i.e., cytokines). Despite this, it is not know whether CB-mediated chemoreflex drive may be affected in CHD. In the present study, we evaluated peripheral CB-mediated chemoreflex drive, cardiac autonomic function, and the incidence of breathing disorders in a murine model of CHD. Compared to age-matched control mice, CHD mice showed enhanced CB-chemoreflex drive (twofold increase in the hypoxic ventilatory response), cardiac sympathoexcitation, and irregular breathing disorders. Remarkably, all these were closely linked to the enhanced CB-mediated chemoreflex drive. Our results showed that mice with CHD displayed an enhanced CB chemoreflex, sympathoexcitation, and disordered breathing and suggest that CBs may be involved in chronic cardiorespiratory alterations in the setting of CHD
Latin American perspectives on sustainability in higher education
No full textAmerican perspectives on sustainability in higher educationLatin America presents several problems that demand debates and complex solutions.Many of these problems have historical roots, resulting from the formation process of these countries.However, these problems have worsened in the postpandemic scenario.The COVID-19 pandemic has destroyed social gains developed through years of improvement, causing millions of people to return to the poverty line (CEPAL, 2021;Gideon, 2020; UN, 2022).The region presents several problems that are directly addressed by the Sustainable Development Goals (SDGs) published by the United Nations (UN, 2015).The informality and deterioration of work (linked with the concerns related to decent work -SDG 8), poverty increasement (that is focused by SDG 1 and hinders the combat of hungry SDG 2) and the uncertainty regarding social programs continuity due to high levels of public debt became common concerns in almost all Latin American countries (directly affecting the SDGs 1, 2, 3, 4 and 8).And, as it is known, the above-mentioned problems are associated with an increase of violence against women (SDG 5), increasing inequalities (SDG 10) and deterioration of teaching conditions (SDG 4).The achievement of the SDGs, which already presented several challenges to be achieved, became even more difficult to be realized in the mentioned scenario as well as the ideals of sustainability based on a fairer society, with more egalitarian social services (UN, 2022).As highlighted by Zhao et al. (2022), besides making the existent barriers more complicated to be solved, the COVID-19 pandemic also created new challenges, reducing globalization and the connection between people.The Higher Education Institutions (HEIs), as centers of teaching, research and extension, have a very important role in this scenario, as they can evidence the most critical issues of Latin American society to be debated, propose solutions for them and, in special, prepare future professionals with a broader conception about their participation and responsibility in society (Sigahi et al., 2022;Sommier et al., 2022; UNESCO, 2017).Interesting initiatives are being developed by HEIs, and it is important to disseminate them to stimulate the development of other ones.Despite these initiatives, it is important to emphasize that Latin American HEIs have faced several problems, such as antiscience movements, brain drain, student learning gaps and mental health problems.And the COVID-19 pandemic scenario aggravated these challenges (Sigahi et al., 2022).Considering this context, this Special Issue aims to evidence important initiatives that are contributing to the sustainable development of Latin American countries.The articles published in this Special Issue assess students' learning experiences and concerns about sustainability, assess the impacts of HEIs on sustainability, assess the relationship between productive systems knowledge and sustainability in HEIs management, provide guidelines and examples for HEIs to develop sustainability related initiatives, among other contributions.We believe that all knowledge and experiences presented in this Specia
Acquisition of a glycosylated B-cell receptor drives follicular lymphoma toward a dark zone phenotype
No full textChannelized, distributed, and disconnected: spatial structure and temporal evolution of the subglacial drainage under a valley glacier in the Yukon
No full textThe subglacial drainage system is one of the main controls on basal sliding but remains only partially understood. Here we expand the analysis of the 8-year dataset of borehole observations on a small, alpine polythermal valley glacier in the Yukon Territory. We presented this dataset in Rada and Schoof (2018), where we described the seasonal evolution of the drainage system and underlined the importance of hydraulic isolation at the glacier bed. These borehole observations constitute a unique dataset, both due to the length of the records and the density of the observations, with up to 157 simultaneously working pressure sensors.Now, to explore the spatial structure of the drainage system and its seasonal progression, we automatically cluster bore holes based on similarities in their water pressure records and follow their evolution through the melt season. Some of these borehole clusters show water pressure variations that suggest they are part of a drainage system connected to the surface meltwater supply, while others show features consistent with hydraulic isolation. The distribution of connected and isolated boreholes suggests that the distributed drainage system we observe comprises a network of small conduits with spacings smaller than the borehole bottom diameter (approximately 25-50 cm). Within these hydraulically connected areas, pressure phase lags, and amplitude attenuation rarely shows the behaviour expected in a diffusive system. This observation suggests that the diffusivity distribution in such areas presents a fine structure at scales smaller than our minimum borehole spacing of 15 m. However, at a glacier-wide scale, we observe that hydraulic connections are ubiquitous in some regions of the bed and permanently absent in others, suggesting large contrasts in diffusivity.Within disconnected areas, boreholes often show small amplitude water pressure variations associated with horizontal normal stress transfers. Such stress transfers seem to play a more important role than previously considered for controlling the effective pressure distribution at the bed.Through the melt season, the evolution of borehole clusters suggests that the diurnal meltwater supply promotes the growth of the low-efficiency drainage systems found early in the season while stimulating the shrinkage and fragmentation of the more efficient drainage systems that appear later in the season. Therefore, an increase in drainage efficiency is associated with the growth of disconnected areas.Our observations support the traditional view of a distributed drainage system early in the melt season that gradually evolves into a progressively more channelized system. However, the most notable difference is the highly heterogeneous distribution of diffusivity that our results suggest and the robust support for disconnected areas. The extent of disconnected areas could be an essential control of basal speed variations. It is possible that even relatively small disconnected areas could have a disproportionate effect on basal speed
