Universidad de Magallanes
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Genetic Diversity and Population Structure of Jubaea chilensis, an Endemic and Monotype Gender from Chile, Based on SNP Markers
No full textJubaea chilensis (Molina) Baill., also named Chilean palm, is an endemic species found in the coastal area of Mediterranean sclerophyllous forest in Chile. It has a highly restricted and fragmented distribution along the coast, being under intense exploitation and anthropogenic impact. Based on 1038 SNP markers, we evaluated the genetic diversity and population structure among six J. chilensis natural groups encompassing 96% of the species distribution. We observed low levels of genetic diversity, a deficit of heterozygotes (mean H-E = 0.024; H-O = 0.014), and high levels of inbreeding (mean F-IS = 0.424). The fixation index (F-ST) and Nei's genetic distance pairwise comparisons indicated low to moderate structuring among populations. There was no evidence of isolation by distance (r = -0.214, p = 0.799). In the cluster analysis, we observed a closer relationship among Culimo, Cocalan, and Candelaria populations. Migration rates among populations were low, except for some populations with moderate values. The K value that best represented the spatial distribution of genetic diversity was Delta K = 3. Habitat fragmentation, deterioration of the sclerophyllous forest, lack of long-distance dispersers, and a natural regeneration deficit may have driven inbreeding and low levels of genetic diversity in the palm groves of J. chilensis. Although extant populations are not at imminent risk of extinction, the rate of inbreeding could increase and migration could decrease if the effects of climate change and human impact become more acute
Telerehabilitation in the high southern latitude. Results of a treatment implementation for people with disabilities during the COVID-19 pandemic Telerehabilitación en alta latitud sur. Resultados de una implementación de tratamiento para personas en situación de discapacidad durante la pandemia de COVID-19
No full textThe health situation after the emergence of COVID-19 has precipitated the use of new technologies and the adaptation of rehabilitation services of all kinds. Objective: To describe the implementation of a telerehabilitation system in patients with different diagnoses of disability living in the high southern latitude during the COVID-19 pandemic. Methods: A system of personalized therapies guided by videoconference was implemented for patients with varying diagnoses of disability. The patients were grouped into three age groups (Minors; Adults; Older Adults) and six types of clinical diagnosis (conditions originating in the perinatal period, diseases of the circulatory system, diseases of the nervous system, diseases of the musculoskeletal system, and connective tissue, mental and behavioural treatments and other diagnoses). The patient's diagnosis, the type of care required, the number of sessions, and the level of satisfaction of each user were evaluated based on the telerehabilitation they received. Results: 101 patients with an average age of 31 ± 26 years participated, 52.5% were male. All of them managed to handle the minimum technologies required for telerehabilitation care. There is a degree of association between the patient's diagnosis and the age group (p <.05), as well as between the diagnosis and the type of care required (p <.05). After implementation, users positively evaluated distance therapy. Conclusions: Telerehabilitation can be implemented in patients with disabilities in areas of high southern latitude, respecting the different stages of the process, to ensure it is correctly delivered
Latitudinal variation of Tegula atra body size (Lesson, 1830) (Gastropod: Trochidae) in shallow waters from southern Chile
No full textAbstract: The great variability of sea environments in Chile is associated with the length of its coastline, which is regulated by several oceanographic processes that outline the distribution, abundance, and morphology of marine species. Tegula atra is a marine gastropod greatly distributed in the southern Pacific, quality that allows it to be a good study model to evaluate the variation of its body size regarding its latitudinal distribution. A total of 236 individuals were collected in six sampling sites between 41.6° ~ 53.6°S. The relationship between weight, height (geometric mean) and its latitudinal distribution was evaluated according to Pearson and to quantile egressions. Related to the latitude, it was noted a positive and substantial correlation (Pearson) between weight and height (ρ > 0.05) moving southward. The results from the quantile regression reflected that both the slope and the R2 value are significant to the latitude with both of the analyzed variables (weight, geometric mean). Among the factors that affect the body size of the T. atra, it is suggested an adaptive differentiation of this genus to different temperatures- which has already been observed in Antarctic species. This reveals an interaction between latitude, fertility and food supply, condition that is reflected by T. atra in the Subantarctic eco-region. However, the study of intermediate areas in southern Chile and the interaction with other abiotic factors (e.g., depth) may elucidate these variations in the body size
Physical Fitness, Screen Time and Sleep Habits According to Obesity Levels in Schoolchildren: Findings from the Health Survey of the Extreme South of Chile
No full textObesity is a worry because it is associated with a greater burden of disease, and it has been shown to be related to the health habits and physical condition of children and adolescents. Objective: To associate physical fitness, screen time, and sleep habits with the different categories of obesity in schoolchildren from the extreme south of Chile. Methods: 583 schoolchildren were included in this cross-sectional analysis. The screen time and sleep habits were measured with the Sleep Self-Report questionnaire, while the physical fitness was assessed with the Alpha Fitness test battery. The Body Mass Index/age (BMI/age) and the Waist-to-Height ratio (WtHr) were used to define adiposity using the following categories: healthy weight/low-risk waist-to-height ratio (H/LR), healthy weight/high-risk waist-to-height ratio (H/HR), overweight/low-risk waist to height ratio (O/LR), and overweight/high-risk waist to height ratio (O/HR). Results: A considerable number of schoolchildren (23.2%) presented sleep problems, while the mean screen time was 9.3 (95% CI: 8.4; 10.1) hours/day. Schoolchildren classified as H/HR showed better physical fitness than the O/HR group but worse physical fitness than the H/LR group. Conclusions: Significant differences were evidenced in the physical fitness between the adiposity categories, which could open future lines of research concerning the characterization of the healthy weight-obese adiposity categories in children
Magallanes Sheep Farming
No full textThe Magallanes region in Chilean Patagonia encompasses 13 million hectares with approximately 3.6 million used for agricultural and livestock systems. This portion is located to the east of the Andean Mountain chain in the rain shadow zone, with annual precipitation increasing along an east to west gradient from 200 to almost 1,000 mm. To fully describe sheep farming in the Magallanes region, many topics need to be addressed, including sheep production and management, existing vegetative communities, livestock-wildlife interactions, and economic diversification into agritourism and another sheep industry products. All these give shape to the story of the development of sheep farming in Magallanes, which is important at the regional and national level. Three key points are identified that together can lead to a successful future for the industry: sustainable management, human resources and the market
Oil Palm's Empty Fruit Bunch as a Sorbent Material in Filter System for Oil-Spill Clean Up
No full textOil pollution such as diesel poses a significant threat to the environment. Due to this, there is increasing interest in using natural materials mainly from agricultural waste as organic oil spill sorbents. Oil palm's empty fruit bunch (EFB), a cost-effective material, non-toxic, renewable resource, and abundantly available in Malaysia, contains cellulosic materials that have been proven to show a good result in pollution treatment. This study evaluated the optimum screening part of EFB that efficiently absorbs oil and the physicochemical characterisation of untreated and treated EFB fibre using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The treatment conditions were optimised using one-factor-at-a-time (OFAT), which identified optimal treatment conditions of 170 degrees C, 20 min, 0.1 g/cm(3), and 10% diesel, resulting in 23 mL of oil absorbed. The predicted model was highly significant in statistical Response Surface Methodology (RSM) and confirmed that all the parameters (temperature, time, packing density, and diesel concentration) significantly influenced the oil absorbed. The predicted values in RSM were 175 degrees C, 22.5 min, 0.095 g/cm(3), and 10%, which resulted in 24 mL of oil absorbed. Using the experimental values generated by RSM, 175 degrees C, 22.5 min, 0.095 g/cm(3), and 10%, the highest oil absorption achieved was 24.33 mL. This study provides further evidence, as the data suggested that RSM provided a better approach to obtain a high efficiency of oil absorbed
Attachment research and anti-racism: learning from Black and Brown scholars
No full textPreliminary evidence suggests that people and scholars of African and/or Latin American and Caribbean origin are often under-represented in mainstream attachment scholarship. In this commentary, we highlight the difficulty of conducting attachment theory research outside of the United States, particularly in Latin American countries. We reflect on the contributions by the authors of this special issue . We also identify (a) ways in which to center the experiences of Black and Brown people and scholars to push the field toward antiracism, and (b) the challenges of attachment theory and research in becoming anti-racist by considering the structural nature of racism
Environmental LCA of Precision Agriculture for Stone Fruit Production
No full textPrecision agriculture is a concept that encompasses various technologies aimed at optimizing the management of agricultural activities. The main aim of this investigation is to evaluate the environmental and economic performance of precision agriculture practices on the production of a stone fruit crop (nectarine) using a life cycle approach and to consider a cradle-to-farm gate scope. The results have been compared against the traditional uniform application (UA). The analysis considers five impact categories, including climate change, photochemical ozone formation, acidification, eutrophication, and water use. The foreground inventory data was provided by a local producer in Southern Spain, and the background information was sourced from commercial Life Cycle Inventory (LCI) databases. The results show that the manufacturing of crop inputs (mainly fertilizers, but also crop management inputs) is responsible for most of the damage generated in all the impact categories, except for water use. The reduced input requirements associated with the application of VA techniques resulted in significantly lower economic costs and environmental savings throughout the life cycle of the production system, which ranged on average between 12-26%
DC Current Harmonics Reduction in Multi-Inverter Topology
No full textThis letter presents a Space Vector Pulse Width Modulation (SVPWM) strategy for reducing the DC-link current harmonics in a multi- Voltage Source Inverter (VSI) topology with common DC-link bus. The DC current harmonic reduction is achieved by phase-shifting the PWM pattern of individual VSIs, with the inverters sharing the system total power. Simulation and experimental results are shown to validate the proposal