Universidad de Magallanes
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SOBREPESO Y OBESIDAD EN GESTANTES CONTROLADAS EN LA ATENCIÓN PRIMARIA DE SALUD, PUNTA ARENAS, CHILE
No full textRESUMEN Objetivo: Relacionar el sobrepeso y obesidad de gestantes con la presencia de patologías del embarazo y tipo de parto. Material y Método: Se estudió a 100 gestantes bajo control en un CESFAM de la ciudad de Punta Arenas, Región de Magallanes y Antártica Chilena, controladas en forma regular entre enero y noviembre del año 2018. Se utilizó fuente secundaria anonimizada con las respectivas autorizaciones y aprobación de un comité de ética. Resultados: Al inicio del embarazo un 66% de las gestantes presentó malnutrición por exceso (37% sobrepeso y el 29% obesidad), al término la proporción aumentó al 74% (33 % sobrepeso más 41% obesidad). Cerca del 97% de las gestantes obesas mantuvo su condición de obesidad. La prevalencia de diabetes gestacional fue de 21% y más frecuente en las gestantes con malnutrición por exceso, alcanzando un 45,6% del total. La prevalencia de parto por cesárea fue de 53,8%, más frecuente en las embarazadas obesas. Se demostró asociación estadísticamente significativa entre malnutrición por exceso y edad de la madre, ganancia de peso y tipo de parto. Conclusiones: La malnutrición por exceso se asoció a presencia de diabetes gestacional y mayor prevalencia de parto por cesárea
Continuing benefits of the Montreal Protocol and protection of the stratospheric ozone layer for human health and the environment
No full textThe protection of Earth's stratospheric ozone (O3) is an ongoing process under the auspices of the universally ratified Montreal Protocol and its Amendments and adjustments. A critical part of this process is the assessment of the environmental issues related to changes in O3. The United Nations Environment Programme's Environmental Effects Assessment Panel provides annual scientific evaluations of some of the key issues arising in the recent collective knowledge base. This current update includes a comprehensive assessment of the incidence rates of skin cancer, cataract and other skin and eye diseases observed worldwide; the effects of UV radiation on tropospheric oxidants, and air and water quality; trends in breakdown products of fluorinated chemicals and recent information of their toxicity; and recent technological innovations of building materials for greater resistance to UV radiation. These issues span a wide range of topics, including both harmful and beneficial effects of exposure to UV radiation, and complex interactions with climate change. While the Montreal Protocol has succeeded in preventing large reductions in stratospheric O3, future changes may occur due to a number of natural and anthropogenic factors. Thus, frequent assessments of potential environmental impacts are essential to ensure that policies remain based on the best available scientific knowledge
Motivational profiles for choosing special education teaching as a career
No full textWith the research reported on here we investigated the motivation of pre-service special education teachers to choose special education as major. The participants were 332 pre-service teachers from 10 universities in Chile. A latent profile analysis with 5 motivational factors of the factors influencing teaching (FIT)-choice scale was carried out to determine the motivational profiles of special education pre-service teachers. Findings show 3 profiles solution as the best model. The disenchanted profile shows low scores for all the motivational factors included in the study. A group of pre-service teachers displayed the highly engaged profile with very high motivational variables. The conventional profile had high scores in the social utility value, intrinsic value, and self-perceptions factors, although the performance in all of them was like that of the other profiles. Knowing the motivational profiles to choose a special education teaching programme can inform policies to attract and retain special education teachers in the field
Peptipedia v2.0: a peptide sequence database and user-friendly web platform. A major update
No full textIn recent years, peptides have gained significant relevance due to their therapeutic properties. The surge in peptide production and synthesis has generated vast amounts of data, enabling the creation of comprehensive databases and information repositories. Advances in sequencing techniques and artificial intelligence have further accelerated the design of tailor-made peptides. However, leveraging these techniques requires versatile and continuously updated storage systems, along with tools that facilitate peptide research and the implementation of machine learning for predictive systems. This work introduces Peptipedia v2.0, one of the most comprehensive public repositories of peptides, supporting biotechnological research by simplifying peptide study and annotation. Peptipedia v2.0 has expanded its collection by over 45% with peptide sequences that have reported biological activities. The functional biological activity tree has been revised and enhanced, incorporating new categories such as cosmetic and dermatological activities, molecular binding, and antiageing properties. Utilizing protein language models and machine learning, more than 90 binary classification models have been trained, validated, and incorporated into Peptipedia v2.0.These models exhibit average sensitivities and specificities of 0.877 +/- 0.0530 and 0.873 +/- 0.054, respectively, facilitating the annotation of more than 3.6 million peptide sequences with unknown biological activities, also registered in Peptipedia v2.0. Additionally, Peptipedia v2.0 introduces description tools based on structural and ontological properties and user-friendly machine learning tools to facilitate the application of machine learning strategies to study peptide sequences
Unveiling the co-phylogeny signal between plunderfish Harpagifer spp. and their gut microbiomes across the Southern Ocean
No full textUnderstanding the factors that sculpt fish gut microbiome is challenging, especially in natural populations characterized by high environmental and host genomic complexity. However, closely related hosts are valuable models for deciphering the contribution of host evolutionary history to microbiome assembly, through the underscoring of phylosymbiosis and co-phylogeny patterns. Here, we propose that the recent diversification of several Harpagifer species across the Southern Ocean would allow the detection of robust phylogenetic congruence between the host and its microbiome. We characterized the gut mucosa microbiome of 77 individuals from four field-collected species of the plunderfish Harpagifer (Teleostei, Notothenioidei), distributed across three biogeographic regions of the Southern Ocean. We found that seawater physicochemical properties, host phylogeny, and geography collectively explained 35% of the variation in bacterial community composition in Harpagifer gut mucosa. The core microbiome of Harpagifer spp. gut mucosa was characterized by a low diversity, mostly driven by selective processes, and dominated by a single Aliivibrio Operational Taxonomic Unit (OTU) detected in more than 80% of the individuals. Nearly half of the core microbiome taxa, including Aliivibrio, harbored co-phylogeny signal at microdiversity resolution with host phylogeny, indicating an intimate symbiotic relationship and a shared evolutionary history with Harpagifer. The clear phylosymbiosis and co-phylogeny signals underscore the relevance of the Harpagifer model in understanding the role of fish evolutionary history in shaping the gut microbiome assembly. We propose that the recent diversification of Harpagifer may have led to the diversification of Aliivibrio, exhibiting patterns that mirror the host phylogeny
Sub-Antarctic Macroalgae as Feed Ingredients for Sustainable Ruminant Production: In Vitro Total Gas and Methane Production
No full textThe sustainable meeting of the global quest for ruminant intensification dictates the need to identify alternative, eco-friendly, and safe feed ingredients. In this sense, macroalgae offer a new paradigm in sustainable ruminant feed supply. This study aimed to investigate the potential of sub-Antarctic macroalgae, including Lessonia flavicans, Macrocystis pyrifera, Gigartina skottbergii, and Ulva Lactuca, regarding their chemical composition, in vitro gas production, and CH4 production. A completely randomized design consisted of a 96 h (h) incubation that included four different species and a control (alfalfa hay) with buffered rumen fluid. In vitro total gas, fermentation characteristics, and CH4 production were evaluated. The highest and the lowest crude protein (CP) contents were for U. lactuca (185.9 g/kg) and G. skottsbergi (86 g/kg), respectively (p < 0.0001). All macroalage had lower levels of natural detergent fiber (NDF) and acid detergent fiber (ADF) compared to alfalfa hay (p < 0.0001). The highest potential of gas production (b) was for M. pyriphera (162.8 mL gas/g DM), followed by alfalfa (119.3 mL gas/g DM). However, G. skottsbergi and M. pyriphera showed the highest dry matter degradability at 96 h (68.49 and 67.62 mg/100 mg, respectively; p < 0.0001) and microbial crude protein (679.8 and 669.8 mg/g, respectively, p < 0.0001). All four tested algae produced lower amounts of methane compared to alfalfa hay (p < 0.0001). After 24 h of incubation, M. pyriphera, L. flavicons, G. skottsbergi, and U. lactuca reduced CH4 by 99.7%, 98.6%, 92.9%, and 79.8%, respectively, when compared with the control. Also, all tested algae had lower (p = 0.0001) CH4 production (ml CH4/g Dry matter degradability, DMD) than alfalfa hay. The current results suggest that M. pyriphera and L. flavicons are promising feed additives for ruminants with eco-friendly production and acceptable CP content and DMD that could effectively mitigate CH4 emissions. Overall, these findings suggest that macroalgae hold promise as a substitute feed source for sustaining ruminant production at the onset of global warming
Plastics in the environment in the context of UV radiation, climate change and the Montreal Protocol: UNEP Environmental Effects Assessment Panel, Update 2023
No full textThis Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment
EVALUACIÓN DE RESULTADOS EN EL APRENDIZAJE SIGNIFICATIVO DE LA MATEMÁTICA EN ESTUDIANTES DE ENSEÑANZA MEDIA
No full textThe current article aims to analyze the evaluation of results in the meaningful learning of mathematics in basic education students in a private high school located in the commune of Punta Arenas-region of Magallanes, it was framed in the quantitative approach, with a basic typology and the design in a non-experimental state, the population consisting of 68 students from the aforementioned high school. To obtain the information, a questionnaire with a Likert scale was used, validated under the judgment of experts and the reliability of Cronbach's Alpha. The main findings in the communication indicator reveal a significant negative perception regarding the effectiveness of the strategies used to promote student dialogue. Furthermore, the indicator ability to solve problems shows an insufficiency of the pedagogical practices used, which would not be able to strengthen the skills necessary for students to address and solve mathematical problems effectively
Assessing Chile's national expansion of urban and artificial coverages between 2000 and 2022
No full textThis study investigates the national expansion of urban and artificial coverages in Chile between 2000 and 2022 using remote sensing techniques. The research employed Google Earth Engine and Landsat imagery to classify land use and land cover (LULC) changes. By analyzing annual cloud-free composites and employing random forest algorithms, the study produced detailed LULC maps, focusing on the 'infrastructure' class, which includes urban areas and major roads. Results indicate a significant 33% increase in infrastructure coverage, growing from approximately 380,000 hectares in 2000 to 510,000 hectares in 2022. This expansion was predominantly observed in seven regions, which accounted for 68% of the total infrastructure area and 83% of the national increase. A notable correlation (0.6) between urban growth and population growth was identified, suggesting that urban expansion is largely driven by demographic changes. However, regions with higher population growth exhibited more vertical urban development. The study highlights the complex interplay between urbanization, population dynamics, and regional planning, emphasizing the need for sustainable development strategies to manage urban growth effectively. Validation efforts showed high classification accuracies, with infrastructure class accuracies averaging 82% for the User and 87% for the Producer across the evaluated years
ASSESSMENT OF NEUROMUSCULAR CONTROL OF LOWER LIMB OF HIGHLY COMPETITIVE SOCCER PLAYERS
No full textThe aim of this study was to assess neuromuscular control in high competition soccer players, since its early identification is of utmost importance to categorize their lower extremity injury risk profile. In this research, three gestures that subject the athlete to develop a correct neuromuscular control were proposed: change of direction (CD), deceleration (D) and vertical jump drop (CSV). Sixty soccer players between 15 and 41 years of age (20.7 +/- 5.9) from the city of Punta Arenas were evaluated, giving as a result that a high percentage presented inadequate neuromuscular control, especially in the CD and D gesture, especially in the variables knee projection angle in the frontal plane (APRPF) and in the relation of the knee with the ground reaction force (GRF), which cause excessive dynamic valgus in the knee