Universidad de Magallanes
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Constellations of Empire. Territorialization and imperial construction in the Hispanic Americas (17th-18th century)
No full textMagellanic ecological identity: comparison between groups from different cultural and regional backgrounds / Identidad ecológica magallánica: comparación entre grupos de orígenes culturales y territoriales diferentes
No full textThis study investigates the relationship between ecological identity and various social and pro-environmental variables among the inhabitants of Southern Patagonia, comparing groups with internal (Chilote) and external (Croatian) migratory ancestry. A total of 212 individuals participated, selected based on their self-categorization as Magellanic, identifying as descendants of Croatian (n = 71), Chilote (n = 66) or other origin (n = 75). We used a non-experimental cross-sectional correlational design to measure regional identity, pro-environmental attitudes, ecological behaviour, essentialism and regionalism. Findings point to differences in ecological variables between the groups compared. Magellanic participants with Chilote ancestry show a stronger relationship between ecology and identity than those with Croatian ancestry. The findings are discussed in terms of the impact of indigenous cultures on the current relationship of Magellanic inhabitants with their natural environment and the importance attributed to territoriality. Este estudio investiga la relación entre la identidad ecológica de los habitantes de la Patagonia Austral y diversas variables sociales y proambientales, comparando grupos con ascendencia migratoria interna (chilotes) y externa (croatas). Participaron 212 personas, seleccionadas según su autocategorización como magallánicos, identificándose como descendientes de origen croata (n = 71), chilote (n = 66) u otro (n = 75). Se empleó un diseño no experimental transversal correlacional para medir la identidad regional, actitudes proambientales, comportamiento ecológico, esencialismo y regionalismo. Los resultados revelan algunas diferencias en las variables ecológicas entre los grupos comparados. Los magallánicos con ascendencia chilota muestran una relación más fuerte entre la ecología y la identidad que aquellos con ascendencia croata. Los hallazgos se discuten en términos del impacto de las culturas originarias en la relación actual de los magallánicos con su entorno natural y la importancia atribuida a lo territorial
Determination of soil carbon content in two contrasting rangeland managements through remote sensing in Chilean Patagonia
No full textThe Magallanes region in Chilean Patagonia has ca. 2.5 million ha of steppe, where the dominant plant species is the tussock grass (Festuca gracillima), which is used for extensive sheep production. The properties have an average of 4,000 ha, then remote sensing tools are necessary to determine plant communities, where high livestock stocking rates for grazing management have generated production losses. Therefore, determining the soil carbon contents in the steppe, depending on the intensity of grazing, would allow to generate management recommendations to sequester more carbon in the soil. Sampling was carried out in three farms under the same type of rangeland, with contrasting management in each farm for this rangeland: a tussock grass (F. gracillima) with low production and another with high production. Three repetitions were obtained per type of rangeland, in 3 soil depths (0-10, 10-20, and 20-30 cm). The carbon contained in the soil samples was analyzed through the muffle calcination method at 360°C for 16 h. The results showed that between 0-10 cm there are significant differences between managements, where the tussock grass with the lowest production had a carbon content of 7.00% while the one with the highest production was 8.38%. In the other soil profiles there are not differences between managements, the latter is important to concentrate works in the first soil profile. These results would allow the region's farms to be diagnosed through remote sensing (NDVI analysis), classifying the plant communities, and indicating in a simpler and more practical way, given the large surfaces, the rangelands with particular management that can sequester more carbon
Quadriceps muscle reaction time in obese children
No full textThis study aimed to determine the influence of obesity, according to body mass index (BMI) and fat mass percentage, on quadriceps muscle reaction times. The study utilized a cross-sectional design. The sample size consisted of 42 schoolchildren (54.5% girls) aged 11 to 12 years old. Participant measurements included weight and height, which were used to categorize individuals based on BMI. Additionally, the electrical bioimpedance technique was employed to categorize participants based on their body fat percentage. A sudden destabilization test of the lower limb was performed to assess the reaction time of the rectus femoris, vastus medialis, and vastus lateralis muscles. The results show that overweight/obese children have a longer muscle reaction time for both the rectus femoris (13 = 18.13; p = 0.048) and the vastus lateralis (13 = 14.51; p = 0.042). Likewise, when the children were classified by percentage of body fat the results showed that overfat/obese children have a longer muscle reaction time for both the rectus femoris (13 = 18.13; p = 0.048) and the vastus lateralis (13 = 14.51; p = 0.042). Our results indicate that BMI and fat mass classification negativity alter the muscle reaction time in children. Overweight/obese or overfat/obese children showed longer reaction times in the rectus femoris and vastus lateralis muscles compared to children with normal weight. Based on these findings, it is suggested that in overweight and obese children, efforts not only focus on reducing body weight but that be complemented with training and/or rehabilitation programs that focus on preserving the normal physiological function of the musculoskeletal system
A novel post-1950 CE atmospheric 14C record for the tropics using absolutely dated tree rings in the equatorial Amazon
No full textIn this study, we present a comprehensive atmospheric radiocarbon (14C) record spanning from 1940 to 2016, derived from 77 single tree rings of Cedrela odorata located in the Eastern Amazon Basin (EAB). This record, comprising 175 high-precision 14C measurements obtained through accelerator mass spectrometry (AMS), offers a detailed chronology of post-1950 CE (Common Era) 14C fluctuations in the Tropical Low-Pressure Belt (TLPB). To ensure accuracy and reliability, we included 14C-AMS results from intra-annual successive cuts of the tree rings associated to the calendar years 1962 and 1963 and conducted interlaboratory comparisons. In addition, 14C concentrations in 1962 and 1963 single -year cuts also allowed to verify tissue growth seasonality. The strategic location of the tree, just above the Amazon River and estuary areas, prevented the influence of local fossil-CO2 emissions from mining and trade activities in the Central Amazon Basin on the 14C record. Our findings reveal a notable increase in 14C from land -respired CO2 starting in the 1970s, a decade earlier than previously predicted, followed by a slight decrease after 2000, signaling a transition towards the fossil fuel era. This shift is likely attributed to changes in reservoir sources or global atmospheric dynamics. The EAB 14C record, when compared with a shorter record from Muna Island, Indonesia, highlights regional differences and contributes to a more nuanced understanding of global 14C variations at low latitudes. This study not only fills critical spatial gaps in existing 14C compilations but also aids in refining the demarcation of 14C variations over South America. The extended tree -ring 14C record from the EAB is pivotal for reevaluating global patterns, particularly in the context of the current global carbon budget, and underscores the importance of tropical regions in understanding carbon -climate feedbacks
Maintenance of a scavenger ancient food web in insular remote areas
No full textVultures are among the most endangered bird species, and changes in their feeding habits due to human activities pose a significant threat to their survival. We studied aspects of the trophic ecology of Andean Condors ( Vultur gryphus) in Tierra del Fuego, an archipelago in the southernmost part of its distribution, and compared it with other six sampling sites across Argentina. We estimated the isotopic niche width, the trophic position, and the extent of marine input on condors at a large spatial scale. Andean Condors in Tierra del Fuego exhibit a unique and substantial reliance on marine food webs, which matches the known historical trophic interactions of the species. In contrast to continental Patagonia, the marine trophic input was not homogeneous among individuals, but structured in two groups along the terrestrial - marine gradient. Marine carrion provided by sea lions, seabirds and stranded cetaceans should be monitored since they can be relevant for the long-term persistence of Andean condors in the area. Moreover, the link of condors with the ocean would also include the movement of marine inputs to terrestrial environments. As most condor samples were obtained in protected areas in the terrestrial-marine interphase, this further emphasizes the importance of preserving these areas in the face of environmental change to conserve not only the species and its landscape but also specific trophic interactions
Medición y análisis de los niveles de intensidad de ruido ambiente, en tres ubicaciones de la zona norte, centro y sur de la ciudad Punta Arenas, durante el segundo semestre del año 2023
No full textINTRODUCCIÓN. El ruido, un sonido molesto multifrecuencial, afecta la salud física y psicológica, interfiriendo con actividades diarias, sueño, estado de ánimo y comunicación, impactando la calidad de vida. En Punta Arenas no se cuenta con datos recientes sobre el ruido ambiental, lo que hace necesario cuantificar y visibilizar los niveles de ruido en distintas zonas de la ciudad. El objetivo del estudio es medir y analizar los niveles de ruido ambiental en tres ubicaciones clave de la zona norte, centro y sur de Punta Arenas durante el segundo semestre de 2023.MATERIALES Y MÉTODOS. Desde un enfoque cuantitativo, se midió el ruido en nueve puntos estratégicos de la ciudad con un sonómetro CESVA. Los datos fueron tabulados y analizados con IBM SPSS Statistics-24, aplicando análisis descriptivo y evaluando la necesidad de pruebas paramétricas o no paramétricas con una significación del 5%.RESULTADOS. Los resultados muestran que los niveles más altos de ruido se registraron en la zona sur, alcanzando 78dB en el Parque María Behety en horario PM. El valor mínimo de 52dB se encontró en la Rotonda Nelda Panicucci en horario AM.CONCLUSIONES. Este estudioaporta datos sobre las zonas más afectadas por contaminación acústica en Punta Arenas, subrayando la importancia de sensibilizar a la población e implementar medidas preventivas que protejan a los residentes y mejoren la calidad de vida en la ciudad
Zona costera: más que un cambio de paradigma
No full textAnales del Instituto de la Patagonia AIP es una revista científica que publica los resultados de investigaciones multidisciplinarias sobre biociencias tanto marina como terrestres, con especial énfasis en ecología, zoología, botánica y sus respectivas subdisciplinas aplicadas. Abordando estos temas en forma específica de cada disciplina o desde una forma transdisciplinaria
On Semi-Vector Spaces and Semi-Algebras with Applications in Fuzzy Automata
No full textIn this paper, we expand the theory of semi-vector spaces and semi-algebras, both over the semi-field of nonnegative real numbers R0+. More precisely, we prove several new results concerning these theories. We introduce to the literature the concept of eigenvalues and eigenvectors of a semi-linear operator, describing how to compute them. The topological properties of semi-vector spaces, such as completeness and separability, are also investigated here. New families of semi-vector spaces derived from the semi-metric, semi-norm and semi-inner product, among others, are exhibited. Furthermore, we show several new results concerning semi-algebras. After this theoretical approach, we apply such a theory in fuzzy automata. More precisely, we describe the semi-algebra of A-fuzzy regular languages and we apply the theory of fuzzy automata for counting patterns in DNA sequences
Compliance with MAB-UNESCO Functions and Management Effectiveness Evaluation between 2017 and 2024: Case Study of the El Cielo Biosphere Reserve, Mexico's Only State-Run Reserve Belonging to MAB-UNESCO
No full textUNESCO's MAB Programme promotes a people-centered conservation strategy to strengthen the sustainability of social and ecological systems. However, there exist knowledge gaps regarding its implementation in specific contexts. For this study, a mixed-methods sequential exploratory design was employed. In the first phase, an initial content analysis of the management program of the El Cielo Biosphere Reserve (CBR) and the functions of the statutory framework of UNESCO's MAB program was conducted. This analysis, which was human-driven but facilitated by artificial intelligence tools, underwent rigorous triangulation and expert validation to strengthen the reliability and robustness of the findings. Subsequently, the Management Effectiveness Tracking Tool (METT3) was issued to researchers, community members, civil servants, and former civil servants related to the management of the CBR. The 2024 results (n = 15) were contrasted with those obtained in 2017 (n = 15) using a quantitative approach consisting of descriptive, non-parametric, and Bayesian statistical techniques. We identified some problems in the implementation of the MAB-UNESCO Programme in the CBR, mainly due to the outdated management program and lack of effective governance, as well as the lack of understanding of the implications of being a MAB-UNESCO biosphere reserve. A numerical trend of deterioration in the effectiveness of the CBR's management was detected, with overall ratings of 44.78% and 29.62% in 2017 and 2024, respectively. This was associated with a lack of regulation, weak coordination among key actors, and a progressive reduction in funding. The findings of this study are useful to guide the transition of the CBR towards a conservation model that responds to current problems and contributes to the advancement of knowledge on the implementation of the MAB Programme in specific contexts