Universidad de Magallanes
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Seed exchange networks: metrics for examining the resilience of social-ecological agricultural systems
No full textAgricultural systems are dynamic social-ecological systems which are rarely examined under relational approaches. The analysis of seed exchange networks represents a growing empirical pathway to relational thinking for examining the resilience of social-ecological agricultural systems and their dynamic cycles. We conducted a literature review to (i) explore the advances of seed exchange network research, and (ii) identify and synthesize the network metrics used for examining social-ecological structures linking human and other-than-human actors to understand the resilience of agricultural systems. Complementarily, we explored what a relational approach to seed exchange network analysis might entail. Our work shows a growing use of network analysis to explore coupled social-ecological relations in agricultural systems. However, in the past quarter century, most seed exchange case studies often omitted the inherent relational nature of network data and lacked recognition of the agency of other-than-human entities in seed exchange networks. We identified over 20 network metrics broadly used in network analysis, including structural and locational metrics such as 'density', 'modularity', and 'centrality'. These metrics have the potential to inform about the dynamics that may either enhance or constrain the resilience of agricultural systems. For example, 'density' and 'centrality' can reveal pathways of agrobiodiversity access and key actors, respectively. This information may enhance the efficiency of agrobiodiversity flows in agricultural systems. Finally, we discuss some practical implications of adopting a relational approach to seed exchange network analysis to better understand people-agrobiodiversity relations under local, regional, and global changes
Chemical composition and trajectories of atmospheric particles at the Machu Picchu Peruvian Antarctic scientific station (62.09° S, 58.47° W)
No full textAntarctica is a remote and relatively pristine region, but the regional transport of aerosols may be a source of pollution, especially in the Antarctic Peninsula. Few studies have characterized atmospheric aerosols and evaluated the contribution of their emission sources. The Peruvian Antarctic research station Machu Pichu (ECAMP, by its Spanish acronym) is located on King George Island in the Antarctic Peninsula. During February 2020, atmospheric particulate mass (PM 10 and PM 2.5 ) was sampled and analyzed to characterize its elemental composition and was supplemented by measurements of equivalent black carbon and aerosol size distributions. Chemical elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), multivariate techniques, and enrichment factors. The most abundant elements in PM 10 and PM 2.5 were Na, Fe, Mg, and Si, with the most important local sources being marine (Na, Mg, Mn, Ca) and crustal (Fe, Al, P). Sources of weathering (Ba and Si) from glacial thawing and sources of combustion linked to the use of oil (V) and emission of black carbon were recorded. Air mass back -trajectory analysis using the HYSPLIT model helped identify external sources of particulate matter in the air masses reaching the ECAMP site. Overall, this study supports the growing evidence of the anthropogenic impact of distant and local sources on the white continent
Spatial practices of the hydrocarbons industry in Chile: 1945-1989
No full textLa implantación de la industria del petróleo en Chile por parte del Estado supuso un ejercicio de desarrollo de un sistema productivo con dimensiones espaciales, que involucró gran parte del territorio nacional. A partir del conjunto de infraestructuras productivas y logísticas levantadas por la industria del petróleo se pretende develar las prácticas y comprender la dimensión espacial de la industria de los hidrocarburos en el país, entre su descubrimiento, en 1945, y el punto de mayor producción, en 1989. Para lograrlo se ha recurrido a archivos, además de fuentes secundarias para determinar las obras de infraestructura, redes y urbanizaciones de la industria petrolera en territorio chileno. A partir de ello se han interpretado las obras y los contextos sobre la base de las prácticas industriales de la actividad, organizando los resultados en función de la cadena productiva en sus fases de exploración y extracción; de transporte y almacenamiento; y de distribución y transformación. La acción del Estado se evidenció como el resultado de una planificación, donde las regiones intervenidas asumieron roles diversos, y que determinó prácticas espaciales diferenciadas desde intervenciones puntuales, la constitución o consolidación de núcleos de industrialización, hasta una red superpuesta de infraestructuras que llevaron a la constitución de un sistema espacial productivo integrado
CaClust: linking genotype to transcriptional heterogeneity of follicular lymphoma using BCR and exomic variants
No full textTumours exhibit high genotypic and transcriptional heterogeneity. Both affect cancer progression and treatment, but have been predominantly studied separately in follicular lymphoma. To comprehensively investigate the evolution and genotype-to-phenotype maps in follicular lymphoma, we introduce CaClust, a probabilistic graphical model integrating deep whole exome, single-cell RNA and B-cell receptor sequencing data to infer clone genotypes, cell-to-clone mapping, and single-cell genotyping. CaClust outperforms a state-of-the-art model on simulated and patient data. In-depth analyses of single cells from four samples showcase effects of driver mutations, follicular lymphoma evolution, possible therapeutic targets, and single-cell genotyping that agrees with an independent targeted resequencing experiment
Vulnerability of small-scale farming livelihoods under climate variability in a globally important archipelago of the Global South
No full textIn recent decades, the pace of change in social-ecological systems has accelerated. The adverse effects of climate variability and extreme events put increasing pressure on rural small-scale farmers' households whose livelihoods depend on nature. However, socioeconomic, political, and institutional changes also affect this group, responsible for producing at least a third of the world's food. This study assessed the influence of climate variability on the spatial distribution of the social-ecological vulnerability of small farmers' livelihoods within a Globally Important Agricultural Heritage System (GIAHS) in southern South America. Data were collected through a questionnaire-based survey of 100 small-scale farmers' households, selected via stratified random sampling. Climate variability and extreme event data spanning 30 years were included, with spatial and temporal resolutions of 1 x 1 km and one year, respectively. Through an indicator-based approach, the study identified 17 vulnerability indicators across Exposure, Sensitivity, and Adaptive Capacity components. The Livelihood Vulnerability Index (LVI) for small-scale farming in the Chiloe Archipelago was calculated at the household level, following the IPCC vulnerability assessment framework and the Sustainable Livelihoods perspective. The findings reveal that LVI values for small-scale farmers ranged from 0.28 (least vulnerable) to 0.54 (most vulnerable). Principal Component Analysis indicated that agricultural extension support, supplementary income, social relations, and ownership of agricultural equipment enhance local adaptive capacity. Spatial autocorrelation analysis revealed clustering in exposure, sensitivity, adaptive capacity, and vulnerability patterns. The finding suggests that extension interventions should strengthen vulnerable households' adaptive capacity by supporting rural livelihood diversification
The Archaeology of Cerro Guido and Sierra Baguales, Chile: Advances in the reconstruction of hunter-gatherer societies in steppe and mountain environments in northeastern Magallanes
No full textThe results of the archaeological prospecting and surveys carried out in the area of Cerro Guido and Sierra Baguales are presented. The research covered four sectors between the north of the Las Chinas River and the area between the Las Flores stream and Palique outpost. Previous records indicate surface lithic evidence associated with the course of the Baguales River and the existence of "chenque" type burial sites at the top of Cerro Guido. During the surveys, 49 isolated surface finds, 23 concentrations of materials and 11 archaeological sites were recorded, three of them under rocky overhangs and eight in the open air. Of the latter, five correspond to large sites, suggesting a wider occupation of the territory by terrestrial hunter -gatherer groups. The test pits allowed a preliminary inference to the exploitation of terrestrial species and the supply of lithic raw materials upstream and/or to high altitude sectors near the Baguales mountain range. New dates extend the known chronology to c. 2500 BP. At the Las Flores Formation, the excavation of a rocky shelter revealed isolated and scattered human skeletal remains in an unusual context for the area, where previously only "chenque" burials had been recorded
Intracellular effects of lithium in aging neurons
No full textLithium therapy received approval during the 1970s, and it has been used for its antidepressant, antimanic, and anti-suicidal effects for acute and long-term prophylaxis and treatment of bipolar disorder (BPD). These properties have been well established; however, the molecular and cellular mechanisms remain controversial. In the past few years, many studies demonstrated that at the cellular level, lithium acts as a regulator of neurogenesis, aging, and Ca2+ 2 + homeostasis. At the molecular level, lithium modulates aging by inhibiting glycogen synthase kinase-3 beta (GSK-3 beta), and the phosphatidylinositol (PI) cycle; latter, lithium specifically inhibits inositol production, acting as a non-competitive inhibitor of inositol monophosphatase (IMPase). Mitochondria and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1 alpha) have been related to lithium activity, and its regulation is mediated by GSK-3 beta degradation and inhibition. Lithium also impacts Ca2+ 2 + homeostasis in the mitochondria modulating the function of the lithium-permeable mitochondrial Na+-Ca2+exchanger +-Ca 2 + exchanger (NCLX), affecting Ca2+ 2 + efflux from the mitochondrial matrix to the endoplasmic reticulum (ER). A close relationship between the protease Omi, , GSK-3 beta, and PGC-1 alpha has also been established. The purpose of this review is to summarize some of the intracellular mechanisms related to lithium activity and how, through them, neuronal aging could be controlled
A camera-trap assessment of the native and invasive mammals present in protected areas of Magallanes, Chilean Patagonia Evaluación con cámaras trampa de mamíferos nativos e invasores presentes en áreas protegidas de Magallanes, Patagonia chilena
No full textThe Chilean Patagonia is characterized by extensive protected areas that encompass most of the region. Mammals are often among the priorities for these protected areas either as conservation targets (e.g., threatened species) or as threats (e.g., invasive species). Camera traps offer a cost-effective alternative to monitor these species, however baseline studies are scarce in the region. Therefore, our objective was to provide an assessment of camera-trapping detection rates for mammals that are present in protected areas of Magallanes, Chilean Patagonia. Between 2015 and 2022 we installed 278 camera traps (9,936 trap-days), distributed in seven protected areas. For each protected area, we calculated the detection rates and proportion of camera traps that detected each species. We recorded 18 mammalian species, including ten native, four domestic, and four invasive species. The culpeo fox (Lycalopex culpaeus) was the most frequently detected species, followed by invasive European hare (Lepus europaeus) and puma (Puma concolor). Endangered species like the huemul (Hippocamelus bisulcus) and southern river otter (Lontra provocax) were detected infrequently, whereas beaver (Castor canadensis) and American mink (Neogale vison) were only recorded in cameras that targeted them. From our data we suggest that generalist monitoring designs are likely to be effective for relatively common species like the culpeo fox. However, when species of interest are associated with specific features of the landscape (e.g., otters and water), other designs are needed. Based on our findings, we provide recommendations for the design of camera-trapping monitoring plans in protected areas
DIFICULTADES DE CONTRAREFERENCIA EN UNA UNIDAD DE ATENCIÓN DE EMERGENCIA: IMPACTO DEL COVID 19
No full textABSTRACT Objective: to describe the influence of the COVID-19 pandemic on counter-referral in an Emergency Care Unit. Method: a descriptive, qualitative study conducted with 13 health professionals. Data were collected through individual, semi-structured interviews and analyzed using the Collective Subject Discourse technique. Results: five speeches were extracted from the interviews about the influence of the pandemic on counter-referral which reveal the difficulties in this process: before the pandemic, overcrowding of specific basic health units that were unable to absorb the population demand and a lack of professionals in teams stood out; the difficulty during the pandemic was in relation to prioritizing care for respiratory symptomatic patients in basic units and the use of communication technology in care and scheduling appointments; there is still difficulty in the transpandemic time in providing care in basic units and the consequent overload in the Emergency Care Unit. Conclusion: COVID-19 had a negative impact on implementing counter-referral with difficulties in logistics, resources and structure, represented by access for the general population, which was even more limited in basic units due to the pandemic
Morphometric variation in subantarctic populations of Liodessus chilensis (Coleoptera: Dytiscidae)
No full textRESUMEN: En insectos acuáticos, el tamaño y la forma corporal son rasgos clave que pueden indicar plasticidad fenotípica o adaptaciones a su paisaje hidrológico. Liodessus chilensis es un pequeño y poco conocido coleóptero acuático que habita cuerpos de agua permanentes y temporales. Acompañando el reporte de la especie en diferentes hábitats de isla Navarino, se presenta una actualización de su descripción. Adicionalmente, se evalúa la variación de la forma corporal de poblaciones de L. chilensis. Los análisis de morfometría geométrica y regresiones multivariadas sobre la forma corporal de L. chilensis muestran variaciones en la parte posterior de los élitros y podrían indicar plasticidad respecto a la naturaleza de los hábitats en que ocurren. La población de charcos temporales presenta élitros más cortos y anchos en su parte terminal, mientras que aquellos que habitan turberas y humedales son más largos y elongados. Adicionalmente, se encontró un efecto alométrico, indicando que además de las diferencias de forma corporal, las poblaciones que habitan charcos temporales suelen ser más pequeñas. La plasticidad de formas de L. chilensis como sus hábitats, permanentes y temporales, pueden ser considerados como centinelas de cambios ambientales. Estos resultados cobran real importancia para la región de Magallanes que ha sido recientemente declarada como propensa a la sequía