Universidad de Magallanes
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Recommendations for the use of antiretroviral agents in people living with HIV in Chile
No full textResumen La terapia antirretroviral ha mejorado significativamente el pronóstico de las personas que viven con el virus de la inmunodeficiencia humana. Sin embargo, su beneficio estará determinado por la correcta utilización de la misma, por lo que estas guías entregan orientaciones para la elección de los esquemas de tratamiento en adultos y niños, con consideraciones para diferentes comorbilidades y estados fisiológicos como grupos de edad o embarazo. Se indican los posibles cambios de terapia por simplificaciones o interacciones y los ajustes de esquemas en casos de fallo virológico. Estas recomendaciones reflejan la posición de sus autores y no necesariamente de sociedades científicas o de la autoridad sanitaria nacional
The second skin of macroalgae: Unveiling the biodiversity of epiphytic microalgae across environmental gradients of the Magellan Subantarctic ecoregion
No full textPrimer registro de Prostemmatinae (Heteroptera: Nabidae) en Chile
No full textThe damsel bug subfamily Prostemmatinae is recorded for the first time from Chile, with the species Pagasa (Lampropagasa) fuscipennis Reuter, 1909. Specimens were obtained from Nuble and Araucanía Regions
Ecosystem engineers show variable impacts on habitat availability for cavity nesters in South American temperate forests
No full textEcosystem engineers are organisms that impact their environment and co-existing species by creating or modifying habitats, and thus they play important roles as drivers of community assembly. We examined whether cavity characteristics and/or habitat attributes associated with cavities provided by 4 ecosystem engineers influence the presence of nests of 3 secondary cavity-nesting birds-Aphrastura spinicauda (Thorn-tailed Rayadito), Tachycineta leucopyga (Chilean Swallow), and Troglodytes aedon (Southern House Wren)-and whether these variations influence their reproductive success. We tested this by: (1) assessing nest presence in cavities supplied by ecosystem engineers and (2) quantifying the reproductive success of secondary cavity nesters as a function of cavity characteristics and habitat attributes supplied by ecosystem engineers. Between 2009 and 2022, we recorded 757 cavities in 546 trees in old-growth and second-growth forests in a Global Biodiversity Hotspot in the Andes of southern Chile. Insect/fungi and Pygarrhichas albogularis (White-throated Treerunner) play a key role as the primary producers of cavities. Insect/fungi generated the cavities for 82% of A. spinicauda nests and 95% of T. aedon nests; in contrast, 57% of T. leucopyga nests were cavities excavated by P. albogularis. Characteristics of cavities (size of cavity entrance, volume, and height above ground) were associated with nest presence of secondary cavity nesters and with reproductive success of A. spinicauda and T. aedon. Habitat attributes such as tree density and canopy cover influenced nest presence for A. spinicauda and T. leucopyga, but did not correlate with the reproductive success of any secondary cavity nester. Bamboo density and forest type were related to reproductive success of A. spinicauda and T. aedon. Diameter at Breast Height of trees was related to the reproductive success of T. leucopyga. This study contributes to understanding the importance of various ecosystem engineers for the conservation of secondary cavity-nesting birds in temperate forests and beyond. center dot Ecosystem engineers are organisms that impact their environment and co-existing species by creating or modifying habitats, and thus they play important roles as drivers of community assembly.center dot We examined the presence of nests of 3 species of secondary cavity nesters and their reproductive success in cavities supplied by 4 ecosystem engineers.center dot Between 2009 and 2022, we recorded 757 cavities in 546 trees in old-growth and second-growth forests in a Global Biodiversity Hotspot in the Andes of southern Chile.center dot Insect/fungi and Pygarrhichas albogularis played a key role as the primary producers of cavities for secondary cavity nesters. The characteristics of cavities were associated with the presence of nests and showed a weaker association with the reproductive success of secondary cavity nesters.center dot Habitat attributes showed a weak association with the presence of nests and the reproductive success of 3 secondary cavity nesters.center dot This study contributes to understanding the importance of various ecosystem engineers for the conservation of secondary cavity-nesting birds. Los ingenieros de ecosistemas son organismos que influyen en su entorno y en las especies coexistentes creando o modificando hábitats, por lo que desempeñan un papel importante como impulsores de la formación de comunidades. Examinamos si las características de las cavidades y/o los atributos de hábitat asociados con las cavidades proporcionados por cuatro ingenieros de ecosistemas influyen en la presencia de los nidos de tres aves que anidan en cavidades secundarias (Aphrastura spinicauda, Tachycineta leucopyga y Troglodytes aedon), y si estas variaciones influyen en suéxito reproductivo. Esto se comprobó: i) evaluando la presencia de nidos en cavidades suministradas por los ingenieros de ecosistemas y ii) cuantificando eléxito reproductivo de los nidificadores secundarios en función de las características de las cavidades y los atributos del hábitat suministrados por los ingenieros de ecosistemas. Entre 2009 y 2022, registramos 757 cavidades en 546árboles de bosques antiguos y de segundo crecimiento a lo largo de un Hotspot de Biodiversidad Global en los Andes del sur de Chile. Los insectos/hongos y el Pygarrhichas albogularis desempeñaron un papel clave como principales productores de cavidades. Los insectos/hongos generaron el 82% de los nidos de A. spinicauda y el 95% de los nidos de T. aedon; en contraste, el 57% de los nidos de T. leucopyga fueron cavidades excavadas por P. albogularis. Las características de las cavidades (tamaño de la entrada de la cavidad, volumen y altura sobre el suelo) se asociaron con la presencia de nidos de los nidificadores secundarios y con eléxito reproductivo de A. spinicauda y T. aedon. Los atributos del hábitat, como la densidad deárboles y la cobertura del dosel, influyeron en la presencia de nidos de A. spinicauda y T. leucopyga, pero no de T. aedon, y no afectaron eléxito reproductor de ninguno de los nidificadores secundarios. La densidad de bambú y el tipo de bosque se relacionaron con eléxito reproductivo de A. spinicauda y T. aedon. El Diámetro a la Altura del Pecho de losárboles se relacionó con eléxito reproductivo de T. leucopyga. Este estudio contribuye a comprender la importancia de varios ingenieros de ecosistemas para la conservación de aves que anidan en cavidades secundarias en el bosque templado y más allá
Estrategias de enseñanza ético-moral en la formación de estudiantes de enfermería: revisión integradora*
No full textObjective: to synthesize the diverse scientific evidence about ethical-moral teaching strategies in Nursing students' training. Methods: an integrative review with search and selection of primary studies in six renowned data sources from the Health field, namely: Web of Science, MEDLINE/ PubMed, CINAHL/EBSCO, LILACS, BDENF and SciELO, be- tween 2018 and 2023. Results: the sample was comprised by 18 studies, selected from a universe of 784 articles. Two categories were generated after integrating the studies on Nursing students' ethical training; these categories associated strengthening the undergraduate students' knowledge, skills and attitudes and ethical-moral educational strategies. Conclusion: in Nursing training, it is necessary to en- courage the development of moral skills and attitudes such as moral sensitivity, empathy, moral resilience and reaso- ning and ethical decision-making, as well as to incorporate professional values. Contributions to practice: this study contributes ethical-moral strategies for the development of ethical-moral skills in Nursing and to consolidate diverse knowledge and skills for ethical, humanistic and socially committed performance, involved with social justice and with defending life
Afforestation and climate mitigation: lessons from Chile
No full textThe Chilean Climate Change Law excludes tree monocultures as a solution to the climate crisis, offering an opportunity for resilience and climate mitigation in Latin America. The Chilean experience with mega -fires in extensive, homogeneous forest plantations provides important lessons that could inform climate policies in other countries
Fine-Scale Spatial Variability of Greenhouse Gas Emissions From a Subantarctic Peatland Bog
No full textPeatlands are recognized as crucial greenhouse gas sources and sinks and have been extensively studied. Their emissions exhibit high spatial heterogeneity when measured on site using flux chambers. However, the mechanism by which this spatial variability behaves on a very fine scale remains unclear. This study investigates the fine-scale spatial variability of greenhouse gas emissions from a subantarctic Sphagnum peatland bog. Using a recently developed skirt chamber, methane emissions and ecosystem respiration (as carbon dioxide) were measured at a submeter scale resolution, at five specific 3 x 3 m plots, which were examined across the site throughout a single campaign during the Austral summer season. The results indicated that methane fluxes were significantly less homogeneously distributed compared with ecosystem respiration. Furthermore, we established that the spatial variation scale, i.e., the minimum spatial domain over which notable changes in methane emissions and ecosystem respiration occur, was <0.56 m(2). Factors such as ground height relative to the water table and vegetation coverage were analyzed. It was observed that Tetroncium magellanicum exhibited a notable correlation with higher methane fluxes, likely because of the aerenchymatous nature of this species, facilitating gas transport. This study advances understanding of gas exchange patterns in peatlands but also emphasizes the need for further efforts for characterizing spatial dynamics at a very fine scale for precise greenhouse gas budget assessment
The hidden biotic face of microbialite morphogenesis - a case study from Laguna de Los Cisnes, southernmost Patagonia (Chile)
No full textMicrobialites provide geological evidence into Earth's early ecosystems, recording long-standing interactions between co-evolving life and the environment. Yet, after more than 100 years of research, the complex interplay between environmental and biological forces involved in microbialite growth is still debated. Laguna de Los Cisnes, located in Chilean Tierra del Fuego, Patagonia, provides a unique opportunity to study these interactions. This lake, which became ice-free around 10 000 years ago, features carbonate microbialites developed by algal-microbial communities. Macroscopically, the organo-sedimentary deposits exhibit a consistent primary crater-like architecture, showcasing macrostructural variations such as dish-shaped, hemispherical, columnar and lenticular morphologies. This study explores the environmental and biological factors shaping microbialite macrostructure by analysing the distribution of dominant morphotypes across the basin. Concurrently, it examines the internal mesostructure and microstructure of microbialites in association with prevailing algal-microbial communities. The incremental development of these communities contributes to the distinct crater-like morphology observed in microbialites from Laguna de Los Cisnes. The mineral encrustation of the green alga Percursaria percursa emerges as a primary driver of lithification, evidenced by the preservation of microfossils within the microstructure of the microbialites. Simultaneously, physical environmental factors, including waves, Langmuir cells and accommodation space influence the location of the algal-microbial carbonate factory, determining the spatial distribution and temporal succession of different crater architecture variants. Laguna de Los Cisnes, hosting well-preserved subfossil outcrops and living microbialites, serves as a remarkable living laboratory for understanding microbialite morphogenesis. This study contributes to a novel model that captures the fundamental role of algal-microbial communities in determining the primary macrostructural architecture of microbialites before environmental factors come into play, merely reshaping this architecture into different morphotypes
An outsider on the Antarctic Peninsula: A new record of the non-native moth Plodia interpunctella (Lepidoptera: Pyralidae)
No full textWe report the first record of the microlepidopteran Plodia interpunctella beyond the South Shetland Islands at the Chilean Yelcho scientific station (64 degrees 52 ' 33.1428 '' S; 63 degrees 35 ' 1.9572 '' W), Doumer Island, close to the west coast of the Antarctic Peninsula. It is notable that P. interpunctella, a globally distributed stored product pest species, exhibits a remarkable capacity for prolonged viability within food storage facilities. The dual challenges of food transportation and storage in the context of Antarctica's challenging operational conditions may have facilitated P. interpunctella's initial arrival to the Antarctic region. Non-perishable food items, such as grains, flour and rice, provide practical options for the bulk food transportation and storage required in the long-term operation of Antarctic research stations. The presence of P. interpunctella in Antarctica, even if restricted to synanthropic environments within buildings, is a clear threat to Antarctic biodiversity, not only through being an invasive species itself but also as a potential vector for other non-native species (bacteria, acari, between others.), which could carry diseases to the native species
The southernmost record for a symphylan: Hanseniella guerreroi sp. nov. (Myriapoda, Scutigerellidae), an inhabitant of the Tierra del Fuego archipelago
No full textA new species of Symphyla, Hanseniella guerreroi sp. nov., is described from specimens collected during expeditions to the Tierra Chile. To the best of our knowledge, this new species represents the southernmost record for a myriapod of the class Symphyla. The morphological affinities of this species with other Hanseniella species from Gondwanan landmasses are discussed, highlighting its potential for studying the impact of the last Quaternary glaciation on soil arthropods in the far south of the continent. This discovery provides important insights into the biogeographic and evolutionary history of soil arthropods in these remote and climatically challenging regions. H. guerreroi sp. nov. is an exemplary species adapted to the harsh environmental conditions of subantarctic ecosystems and contributes significantly to our understanding of biodiversity and ecological dynamics in such challenging habitats