Repositorio académico de acceso abierto (Univ. Autonóma de Chile)
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Identidad docente de profesores(as) que ejercen en escuelas diferentes: Montessori y Waldorf-Steiner
No full textThis article is a qualitative research about the perspective of teachers working in Montessori and Waldorf-Steiner schools, in the Chilean educational context. The objective is to analyze the teacher identity specifically in the types of school, in order to understand the way they interpret, assume and define their work in unique teaching contexts. Semistructured interviews were conducted with six Chilean teachers, which were transcribed and analyzed using Grounded Theory techniques, and then discussed with the participants themselves. The emerging categories highlight that, despite a high Montessori and Waldorf-Steiner pedagogical normativity, teachers recognize a motivating teaching autonomy and describe enabling professional contexts that also contribute to the active construction of their professional self-image. At the same time, they identify themselves as professionals in disruption with the traditional system and part of a small and limited community. Consequently, the hypothesis of a professional identity based on a democracy of learning in the various dimensions of educational work is raised. We suggest delving into the identity arrangements of teachers in different schools, as well as questioning their role in the educational debate beyond their pedagogical boundaries. © This content is licensed under a Creative Commons attribution-type BY 4.0.Universidad Autónoma de Chil
Association of Early Sports Practice with Cardiovascular Risk Factors in Community-Dwelling Adults: A Retrospective Epidemiological Study
No full textBackground: Sports practice in childhood and adolescence has been inversely related to the chances of developing cardiovascular risk factors (CRFs). However, it is not clear whether sports practice in childhood and adolescence could be inversely related to CRF in adult life. Objectives: This study aimed to analyze the association between early sports practice and cardiovascular risk factors in a randomized sample of community-dwelling adults. Methods: For this, 265 adults aged ≥ 18 years composed the sample. Cardiovascular risk factors of obesity, central obesity, diabetes, dyslipidemia, and hypertension were collected. Early sports practice was retrospectively self-reported using an appropriate instrument. Total physical activity level was assessed by accelerometry. The association between early sports practice and cardiovascular risk factors in adulthood was analyzed by binary logistic regression, adjusted for sex, age, socioeconomic status, and moderate-to-vigorous physical activity. Results: Early sports practice was observed in 56.2% of the sample. The prevalence of central obesity (31.5 vs. 50.0%; p = 0.003), diabetes (4.7% vs. 13.7%; p = 0.014), dyslipidemia (10.7% vs. 24.1%; p = 0.005), and hypertension (14.1% vs. 34.5%; p = 0.001) was lower in participants who reported early sports practice. Participants who reported early sports practice in childhood and adolescence were, respectively, 60% (OR = 0.40; 95% CI 0.19–0.82) and 59% (OR = 0.41; 95% CI 0.21–0.82) less likely to have hypertension in adult life when compared to those with no early sports practice, independently of sex, age, socioeconomic status, and habitual physical activity level in adulthood. Conclusion: Early sports practice in childhood and adolescence was a protective factor for hypertension in adulthood.Universidad Autónoma de Chil
Study of properties and behavior of concrete containing EAF slag as coarse aggregate
No full textElectric arc furnace slag (EAFS) is an attractive by-product due to its suitability as a replacement aggregate, the use of which helps to reduce the demand for natural resources. The aim of the present study is to determine the suitability of EAFS as a 50% and 100% replacement for coarse concrete aggregates, by evaluating its physical, mechanical and chemical properties. Slump and workability of concretes with EAFS decreased due to the shape and texture of the aggregate. Compressive strength, flexural strength and modulus of elasticity of concretes with EAFS improved by up to 30.9%, 35.7% and 25.0% over the control series, respectively. Absorption, porosity and ultrasonic pulse velocity were favored as well, and the greater density can be beneficial in some cases; however, thermal conductivity and capillary absorption were slightly affected. Considering the good results, EAFS is considered a viable alternative for use as a coarse aggregate replacement in concretes. © 2023 The AuthorsFondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1211135); Agencia Nacional de Investigación y Desarrollo, ANIDUniversidad Autónoma de Chil
Profesores de Educación Física en activo v/s en formación: nivel de conocimiento sobre el Trastorno por Déficit Atencional e Hiperactividad en escolares
No full textAttention Deficit Hyperactivity Disorder (ADHD) is the most common neurobiological disorder of childhood, of genetic and multifactorial origin, with a neurobiological substrate that mainly affects the frontal lobe and its connections with the basal ganglia. The research deals with the level of knowledge of Physical Education pedagogical professionals in relation to Attention Deficit Hyperactivity Disorder (ADHD). Objective: The aim of this research is to compare the level of knowledge among active and trainee physical education teachers in relation to ADHD in schoolchildren. Method: Under a non-experimental design, with a quantitative approach and comparative scope. Instruments: A questionnaire on the knowledge of attention deficit hyperactivity disorder was applied. Results: Both active teachers and trainee teachers of Physical Education showed a low level of knowledge of ADHD, answering less than 50% of the questions correctly. Conclusion: The results show that there is a need to increase specific training in ADHD for teachers both during their initial and in-service training, with the intention of having a greater knowledge of this disorder, knowing how to relate in the classroom with students who present inappropriate behaviour, and in turn helping with the early detection of ADHD. © Copyright: Federación Española de Asociaciones de Docentes de Educación Física (FEADEF)Universidad Autónoma de Chil
Distanciamiento social y lesiones en estudiantes durante el ejercicio físico y/o deporte
No full textIn the last two years, the scientific literature has revealed the negative physical, psychological and affective-social repercussions of confinement and social distancing measures, being the sports field, in particular, the one analyzed in this study. The purpose of this research is to relate the frequency and severity of the injury in physical exercise and/or sport with the population’s perception of the importance of social distancing and the use of masks to reduce Covid-19 infections. The study sample is made up of 203 participants (95 men and 108 women), with a mean age of 16 years (SD= 6), belonging to schools in the province of Alicante and Spanish universities. A cross-sectional and correlational design was acquired with a selective data collection strategy using self-report measures. To evaluate the injuries, a self-report record was developed and for the population’s perception of the usefulness of social distancing measures, the Perception Questionnaire on Causal Factors of COVID-19 (CPFC-COVID-19) was used. The results indicate that those subjects who perceive more important the maintenance of a safety distance and the use of masks to stop infections, present high levels in the dimension of social distancing for mild and moderate sports injuries, while those that give less relevance are seriously or very seriously injured. The relationships of these variables are discussed, as well as the applicability of the results. © 2023, Universidad Catolica San Antonio Murcia. All rights reserved.Universidad Internacional de La Rioja, UNIRUniversidad Autónoma de Chil
Neuroprotection in metabolic syndrome by environmental enrichment. A lifespan perspective
No full textMetabolic syndrome (MetS) is defined by the concurrence of different metabolic conditions: obesity, hypertension, dyslipidemia, and hyperglycemia. Its incidence has been increasingly rising over the past decades and has become a global health problem. MetS has deleterious consequences on the central nervous system (CNS) and neurological development. MetS can last several years or be lifelong, affecting the CNS in different ways and treatments can help manage condition, though there is no known cure. The early childhood years are extremely important in neurodevelopment, which extends beyond, encompassing a lifetime. Neuroplastic changes take place all life through — childhood, adolescence, adulthood, and old age — are highly sensitive to environmental input. Environmental factors have an important role in the etiopathogenesis and treatment of MetS, so environmental enrichment (EE) stands as a promising non-invasive therapeutic approach. While the EE paradigm has been designed for animal housing, its principles can be and actually are applied in cognitive, sensory, social, and physical stimulation programs for humans. Here, we briefly review the central milestones in neurodevelopment at each life stage, along with the research studies carried out on how MetS affects neurodevelopment at each life stage and the contributions that EE models can provide to improve health over the lifespan. Copyright © 2023 Kobiec, Mardaraz, Toro-Urrego, Kölliker-Frers, Capani and Otero-Losada.Universidad Autónoma de Chil
First insights about orexigenic activity and gastrointestinal tissue localization of ghrelin from Corvina drum (Cilus gilberti)
No full textThe croaker Cilus gilberti commonly known as Corvina drum is considered a target marine species for the diversification of Chilean aquaculture. To optimize culture conditions, molecular markers for appetite regulation must be examined. Ghrelin, a gastrointestinal peptide, plays a stimulatory role in the food intake of mammals and teleost fish. Nevertheless, even though the appetite-controlling system is considered relatively well conserved among vertebrates, the bioactivity of these molecules should be analyzed in each fish species. Therefore, this study aimed to investigate the expression and orexigenic ability of C. gilberti ghrelin. After the pre and postprandial period, the stomach expression of ghrelin mRNA in juvenile C. gilberti was analyzed. The coding sequence of C. gilberti ghrelin was used to identify the mature peptide and then chemically synthesized. The orexigenic ability of acylated ghrelin (cgGhre) and non-acylated (D-cgGhre) ghrelin was tested in C. gilberti juveniles. Moreover, the blood and the gastrointestinal location of synthetic ghrelin after intraperitoneal injection were measured. The results showed that the stomach has the highest expression of ghrelin mRNA, and that ghrelin levels increased in the preprandial period and diminished after it. There were no differences in the secondary structure of D-cgGhre compared to cgGhre but the peptide with the serine acylation stabilized its unordered conformation. However, the highest cumulative feed intake occurred in fish intraperitoneally injected with cgGhre. In addition, synthetic ghrelin was maintained in the C. gilberti blood until 8 h post-injection (hpi). Finally, biotinylated ghrelin allowed localizing the synthetic peptide in digestive tissue, mainly in the stomach and pyloric caeca. The mRNA expression of the growth hormone secretagogue receptor (GHS-R), also known as the ghrelin receptor, in gastrointestinal organs supports the idea of peripheral orexigenic regulation in these tissues. In conclusion, results suggest that C. gilberti ghrelin conserves the orexigenic ability reported in other teleost fish with a regulatory role in the gastrointestinal tract (GIT) of the Corvina drum. This is the first report demonstrating the uptake and distribution of a small orexigenic peptide in the digestive tissues of a South American sciaenid. Although ghrelin is a promising molecular marker for feed intake analysis in C. gilberti culture, further research is needed to continue evaluating the effects of aquaculture practices on peripheral appetite signalizer. © 2023ANID-Chile; Ministerio de Educación , Ciencia y Tecnología of the Government of El Salvador, (3200440); Ministerio de Educación, Ciencia y Tecnología of the Government of El Salvador; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (11180042, 1210056, 1230712, 15PTEC-45862, FOVI220076)Universidad Autónoma de Chil
The effect of exercise on suicidal ideation and behaviors: A systematic review and meta-analysis of randomized controlled trials
No full textBackground: Although exercise may positively impact those with mental or other medical illnesses, there is a lack of understanding on how it influences suicidal ideation or risk. Methods: We conducted a PRISMA 2020-compliant systematic review searching MEDLINE, EMBASE, Cochrane, and PsycINFO from inception to June 21, 2022. Randomized controlled trials (RCTs) investigating exercise and suicidal ideation in subjects with mental or physical conditions were included. Random-effects meta-analysis was conducted. The primary outcome was suicidal ideation. We assessed bias of studies with risk of bias 2 tool. Results: We identified 17 RCTs encompassing 1021 participants. Depression was the most included condition (71 %, k = 12). Mean follow up was 10.0 weeks (SD = 5.2). Post-intervention suicidal ideation (SMD = -1.09, CI -3.08–0.90, p = 0.20, k = 5) was not significantly different between exercise and control groups. Suicide attempts were significantly reduced in participants randomized to exercise interventions as compared to inactive controls (OR = 0.23, CI 0.09–0.67, p = 0.04, k = 2). Fourteen studies (82 %) were at high risk of bias. Limitations: This meta-analysis is limited by few, underpowered and heterogenous studies. Conclusion: Overall, our meta-analysis did not find a significant decrease in suicidal ideation or mortality between exercise and control groups. However, exercise did significantly decrease suicide attempts. Results should be considered preliminary, and more and larger studies assessing suicidality in RCTs testing exercise are needed. © 2023 Elsevier B.V.Universidad Autónoma de Chil
Novel deep learning method for coronary artery tortuosity detection through coronary angiography
No full textCoronary artery tortuosity is usually an undetected condition in patients undergoing coronary angiography. This condition requires a longer examination by the specialist to be detected. Yet, detailed knowledge of the morphology of coronary arteries is essential for planning any interventional treatment, such as stenting. We aimed to analyze coronary artery tortuosity in coronary angiography with artificial intelligence techniques to develop an algorithm capable of automatically detecting this condition in patients. This work uses deep learning techniques, in particular, convolutional neural networks, to classify patients into tortuous or non-tortuous based on their coronary angiography. The developed model was trained both on left (Spider) and right (45°/0°) coronary angiographies following a fivefold cross-validation procedure. A total of 658 coronary angiographies were included. Experimental results demonstrated satisfactory performance of our image-based tortuosity detection system, with a test accuracy of (87 ± 6)%. The deep learning model had a mean area under the curve of 0.96 ± 0.03 over the test sets. The sensitivity, specificity, positive predictive values, and negative predictive values of the model for detecting coronary artery tortuosity were (87 ± 10)%, (88 ± 10)%, (89 ± 8)%, and (88 ± 9)%, respectively. Deep learning convolutional neural networks were found to have comparable sensitivity and specificity with independent experts’ radiological visual examination for detecting coronary artery tortuosity for a conservative threshold of 0.5. These findings have promising applications in the field of cardiology and medical imaging. © 2023, The Author(s).DEEP-HybridDataCloud H2020, (777435); IFCA-CSIC-UC; Universidad de Cantabria and Consejería de Universidades; Universidad Autónoma de Coahuila, UAdeC; European Commission, EC; Consejo Superior de Investigaciones Científicas, CSICUniversidad Autónoma de Chil
Metabologenomics analysis of Pseudomonas sp. So3.2b, an Antarctic strain with bioactivity against Rhizoctonia solani
No full textIntroduction: Phytopathogenic fungi are a considerable concern for agriculture, as they can threaten the productivity of several crops worldwide. Meanwhile, natural microbial products are acknowledged to play an important role in modern agriculture as they comprehend a safer alternative to synthetic pesticides. Bacterial strains from underexplored environments are a promising source of bioactive metabolites. Methods: We applied the OSMAC (One Strain, Many Compounds) cultivation approach, in vitro bioassays, and metabolo-genomics analyses to investigate the biochemical potential of Pseudomonas sp. So3.2b, a strain isolated from Antarctica. Crude extracts from OSMAC were analyzed through HPLC-QTOF-MS/MS, molecular networking, and annotation. The antifungal potential of the extracts was confirmed against Rhizoctonia solani strains. Moreover, the whole-genome sequence was studied for biosynthetic gene clusters (BGCs) identification and phylogenetic comparison. Results and Discussion: Molecular networking revealed that metabolite synthesis has growth media specificity, and it was reflected in bioassays results against R. solani. Bananamides, rhamnolipids, and butenolides-like molecules were annotated from the metabolome, and chemical novelty was also suggested by several unidentified compounds. Additionally, genome mining confirmed a wide variety of BGCs present in this strain, with low to no similarity with known molecules. An NRPS-encoding BGC was identified as responsible for producing the banamides-like molecules, while phylogenetic analysis demonstrated a close relationship with other rhizosphere bacteria. Therefore, by combining -omics approaches and in vitro bioassays, our study demonstrates that Pseudomonas sp. So3.2b has potential application to agriculture as a source of bioactive metabolites. Copyright © 2023 Maimone, Junior, de Oliveira, Rojas-Villalta, de Lira, Barrientos and Núñez-Montero.FONDECYT-1210563, (11230475); Network for Extreme Environments Research, (NXR17-0003); São Paulo State Funding Agency, Brazil; Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP, (2019/17721-9, 2022/01529-4); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES; Comisión Nacional de Investigación Científica y Tecnológica, CONICYT; Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq, (141501/2020-0, 142260/2020-4); Instituto Tecnológico de Costa Rica, ITCR, (5402-1510-1035); Institut chilien de l'Antarctique, INACH; Agencia Nacional de Investigación y Desarrollo, ANIDUniversidad Autónoma de Chil