Universidad de Magallanes
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Protocol Study: Resistance Training Program, Nutritional, Sleep, and Screen Use Recommendations in Schoolchildren from Educational Centers in the Extreme South of Chile
No full textBackground: Childhood obesity has tripled, reaching critical levels of malnutrition. This factor is directly associated with a poorer health-related quality of life of the child and adolescent population. This article presents the study protocol of the project "Strong schoolchildren with a healthy lifestyle" (EF-Salud), which seeks to analyze the effects of a multicomponent program based on muscle strength exercises, sleep nutritional recommendations, and the use of screens in Chilean educational centers with extremely cold weather. Methods: The study protocol of a randomized controlled trial with a pre- and post-test conducted according to the CONSORT statement is reported. The total sample (n = 144) will be schoolchildren from six different school years, four of which will perform an intervention and two control. Intervention group 1 (from two different school years) will receive a muscular strength exercise program in the classroom once a day from Monday to Friday for six months and nutritional, sleep, and use of screens recommendations once a week. Intervention group 2 (from two different school years) will receive a program of nutritional, sleep, and use of screens recommendations once per week for six months. The control group (from two different school years) will carry out their usual school day in relation to physical education classes. Before and after the intervention, the investigators will evaluate the cardiovascular risk, physical condition, and lifestyle related to sleep and use of screens. Expected results: The schoolchildren in intervention group 1 will obtain significant results in increased strength, decreased cardiovascular risk, improved sleep habits, and fewer hours of screen use compared to the other two groups
Model-based assessment of sampling protocols for infectious disease genomic surveillance
No full textGenomic surveillance of infectious diseases allows monitoring circulating and emerging variants and quantify-ing their epidemic potential. However, due to the high costs associated with genomic sequencing, only a limited number of samples can be analysed. Thus, it is critical to understand how sampling impacts the information generated. Here, we combine a compartmental model for the spread of COVID-19 (distinguishing several SARS-CoV-2 variants) with different sampling strategies to assess their impact on genomic surveillance. In particular, we compare adaptive sampling, i.e., dynamically reallocating resources between screening at points of entry and inside communities, and constant sampling, i.e., assigning fixed resources to the two locations. We show that adaptive sampling uncovers new variants up to five weeks earlier than constant sampling, significantly reducing detection delays and estimation errors. This advantage is most prominent at low sequencing rates. Although increasing the sequencing rate has a similar effect, the marginal benefits of doing so may not always justify the associated costs. Consequently, it is convenient for countries with comparatively few resources to operate at lower sequencing rates, thereby profiting the most from adaptive sampling. Finally, our methodology can be readily adapted to study undersampling in other dynamical systems
Impact of Manufacturing Tolerances on Axial Flux Permanent Magnet Machines with Ironless Rotor Core: A Statistical Approach
No full textAxial Flux Permanent Magnet (AFPM) machines with ironless rotors are an attractive and recently studied solution in low-speed applications, due to their potentially high power/weight ratio, high aspect ratio, and high efficiency. Nevertheless, these machines are prone to be affected by manufacturing tolerance during its fabrication process and consequently, the magnets may move freely inside the rotor structure. This work presents a statistical analysis of manufacturing tolerances of an AFPM machine with an ironless rotor, considering several magnet fault types. A computationally efficient superposition method is developed and implemented to obtain both the cogging torque and rated torque considering several tolerance combinations with acceptable accuracy. The results obtained from a statistical analysis of 10,000 designs of a two-stator one rotor tooth coil winding AFPM (TCW-AFPM) machine allowed us to identify the parameters with the most impact on relevant performance indicators and disclosed a substantial increase in cogging and ripple torque when unavoidable combined tolerances are present
On a bite case of Steatoda triangulosa (Walckenaer) (Arachnida: Theridiidae) on a human being
No full textThe second case of a bite by the "triangulate false widow" Steatoda triangulosa is reported on a human being. The case occurred in San Vicente, Buenos Aires, Argentina on a female 31 years old victim, who woke up felling a nuisance and spotting the spider on her arm. The spider inflicted two bites causing typical steatodism symptoms including local and radiating pain and malaise which lasted for about a day. In addition, the appearance of an erythema on each bite side that lasted about 10 days plus a haematoma in the first bite site which lasted for 3 days. The implications of the case in the context of current research in steatodism is discussed
Hummingbird diversity in a fragmented tropical landscape in the Choco biogeographic zone
No full textForest loss and fragmentation drive widespread declines in biodiversity. However, hummingbirds seem to exhibit relative resilience to disturbance, characterized by increasing abundance alongside declining species richness and evenness. Yet, how widespread this pattern may be, and the mechanisms by which it may occur, remain unclear. To fill in this knowledge gap, we investigated habitat-and site-level patterns of diversity, and community composition of hummingbirds between continuous forest (transects n = 16 in similar to 3500 ha) and more disturbed surrounding fragments (n = 39, 2.5-48.0 ha) in the Choco rain forest of northwestern Ecuador. Next, we assessed within-patch and patch-matrix characteristics associated with hummingbird diversity and composition. We found higher hummingbird species richness in forest fragments relative to the continuous forest, driven by increased captures of rare species in fragments. Community composition also differed between continuous forest and fragments, with depressed evenness in fragments. Increased canopy openness and density of medium-sized trees correlated with hummingbird diversity in forest fragments, although this relationship became nonsignificant after applying false discovery rate (p < .01). Higher species richness in fragments and higher evenness in the continuous forest highlight the complex trade-offs involved in the conservation of this ecologically important group of birds in changing Neotropical landscapes
The delayed effect of climatic conditions on pre-fledging nestling haematocrit in a suboscine species in Patagonia
No full textHaematocrit, the proportion of blood comprising erythrocytes, is often used as a proxy of individual condition. Nestling haematocrit is influenced by several factors but ambient temperature is generally agreed as a key driver. It is unclear which day(s) in embryonic or nestling development are most influential in determining pre-fledgling haematocrit. This is important, because if we are able to identify what day(s) nestlings are physiologically most vulnerable to climatic conditions, this may inform future conservation management and help mitigate the effects. We investigated the effect of ambient temperature, precipitation, body size, brood size, age, food abundance and habitat on nestling haematocrit in Aphrastura spinicauda (thorn-tailed rayaditos). We collected this data from two climatically different locations in Chile: northern Patagonia (Pucon) and Sub-Antarctic Patagonia (Navarino Island), located similar to 1800 km further south. We aimed to identify the key drivers of nestling haematocrit and find when nestlings are physiologically most vulnerable to climatic conditions. We confirm that ambient temperature is the key driver of nestling haematocrit, with increasing ambient temperatures nestling haematocrit decreased. However, precipitation also affected haematocrit in the late incubation stage. At low and high precipitation, nestling haematocrit was low and is optimum in light rainfall. Our results show a delayed effect of ambient temperature and precipitation in late incubation and on the day of hatching which can determine pre-fledgling haematocrit, which may cause lower post-fledgling fitness. We found that climatic conditions on the day haematocrit was collected was not important in determining haematocrit. We found that haematocrit was higher in the sub-Antarctic area and that higher temperatures and precipitation on the day of hatching will result in lower nestling haematocrit and poorer pre-fledgling condition. As atmospheric temperatures rise, nestling fitness is at risk. This is a threat to many bird species, especially those in locations vulnerable to climate breakdown
SOUTHWESTERN COAST OF CHILE (PATAGONIA) CARTOGRAPHIC IMAGE AT XVI CENTURY
No full textThe evolution of the initial geographic knowledge of the southwestern coast of Chile, from the time of its invention until the end of the 16th century, with the vicissitudes of its cartographic recognition after overcoming the official secrecy imposed by the Hispanic monarchy to the news obtained after the first explorations
c-Abl Phosphorylates MFN2 to Regulate Mitochondrial Morphology in Cells under Endoplasmic Reticulum and Oxidative Stress, Impacting Cell Survival and Neurodegeneration
No full textThe endoplasmic reticulum is a subcellular organelle key in the control of synthesis, folding, and sorting of proteins. Under endoplasmic reticulum stress, an adaptative unfolded protein response is activated; however, if this activation is prolonged, cells can undergo cell death, in part due to oxidative stress and mitochondrial fragmentation. Here, we report that endoplasmic reticulum stress activates c-Abl tyrosine kinase, inducing its translocation to mitochondria. We found that endoplasmic reticulum stress-activated c-Abl interacts with and phosphorylates the mitochondrial fusion protein MFN2, resulting in mitochondrial fragmentation and apoptosis. Moreover, the pharmacological or genetic inhibition of c-Abl prevents MFN2 phosphorylation, mitochondrial fragmentation, and apoptosis in cells under endoplasmic reticulum stress. Finally, in the amyotrophic lateral sclerosis mouse model, where endoplasmic reticulum and oxidative stress has been linked to neuronal cell death, we demonstrated that the administration of c-Abl inhibitor neurotinib delays the onset of symptoms. Our results uncovered a function of c-Abl in the crosstalk between endoplasmic reticulum stress and mitochondrial dynamics via MFN2 phosphorylation
Biocultural Calendars Across Four Ethnolinguistic Communities in Southwestern South America
No full textSince the mid-20th century, the so-called Great Acceleration (sensu Steffen et al., 2007, https://doi.org/10.1579/0044-7447(2007)36[614:TAAHNO]2.0.CO;2) has amplified processes of ecosystem degradation, extinction of biological species, displacement of local peoples, losses of languages, and cultural diversity. These losses are still underperceived by the academic community, and by a global society that is disconnected from biocultural diversity. To reconnect society with biocultural diversity, we integrate temporal and spatial dimensions of seasonal cycles, by combining two conceptual frameworks: ecological calendars and the "3Hs" model of the biocultural ethic (sensu Rozzi, 2012, https://doi.org/10.5840/enviroethics20123414). The latter values the vital links between human and other-than-human co-inhabitants, their life habits (e.g., cultural practices of humans or life cycles of other-than-human species), and the structure and processes of their shared habitats. This integration enhances an understanding of links between cultural practices and the life cycles of biocultural keystone species. As a synthesis, we use the term biocultural calendars to emphasize their co-constitutive nature that result from interactions between dynamic biophysical and cultural processes embedded in specific ecosystems and cultures. These calendars link astronomical, biological, and cultural seasonal cycles that sustain life and enhance the integration of Indigenous and scientific knowledge to confront challenges of climate change faced from local to global scales. To illustrate this integration, we examine cultural practices and socio-environmental changes across four contrasting ethnolinguistic communities in southwestern South America, from southern to northern Chile along a marked climatic gradient to show the broad application of the concept of biocultural calendars. Plain Language Summary We combine ecological calendars and the biocultural ethic. The first refers to natural or seasonal calendars and focuses on the temporal scale of life cycles and other ecological phenomena observed at a given place. The second emphasizes the vital links among human and non-human co-inhabitants, their habits (e.g., cultural practices of humans or life cycles of other-than-human species) in shared habitats (the "3Hs" of the biocultural ethic). Close observation of biological and cultural diversity, and their interrelationships (in short, biocultural diversity), synchronizes cultural practices with natural processes at specific places. This synchrony is particularly relevant in the context of climate change because by being locally attuned, communities enhance their capacity to adapt their activities to the variability of temperature, rainfall, and other climatic events. In this article we use the term biocultural calendars to more closely understand the links between different life habits in contrasting habitats and annual seasons. In this way, biocultural calendars provide an understanding of biological and cultural heterogeneity in different seasons and regions of the world that can help us adapt to a rapidly changing world
