Repositorio académico de acceso abierto (Univ. Autonóma de Chile)
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School engagement profiles in Chilean secondary students
No full textSchool engagement is considered a key variable in promoting educational trajectories. Previous research shows that maintaining high levels of school engagement is fundamental, given its association with multiple academic results and lower-risk behaviors. This article aims to show how school engagement profiles (based on the behavioral, affective, and cognitive subdimensions) relate to academic achievement (math and language), contextual factors (family, teachers, and peer support), and gender. This study involved 527 students enrolled in the 1st year of secondary education in public schools in Chile. All students came from vulnerable schools. Our study used cluster analysis to identify students’ profiles. We identified the existence of three different profiles of school engagement (high, medium, and low) considering the three subdimensions of school engagement (behavioral, affective and cognitive). Secondly, ANOVA analysis showed differences in language and math academic achievement scores between the profiles, where higher engagement students showed higher academic performance in language and math. These findings are consistent with previous studies showing that contextual factors strongly influence school engagement and better behavioral engagement in female than male students. It will discuss the pertinence of person-centered approaches focusing on combinations of variables within students rather than taking each variable as the focal point when analyzing goals. These techniques are a favorable methodological alternative to investigate why some students have better results than others instead of just ranking students by their performance. It will conclude with some future lines of research and practical implications.Universidad Autónoma de Chil
Modified poly (vinylidene fluoride) nanomembranes for dye removal from water – A review
No full textWater contamination due to soluble synthetic dyes has serious concerns. Membrane-based wastewater treatments are emerging as a preferred choice for removing dyes from water. Poly(vinylidene fluoride) (PVDF)-based nanomembranes have gained much popularity due to their favorable features. This review explores the application of PVDF-based nanomembranes in synthetic dye removal through various treatments. Different fabrication methods to obtain high performance PVDF-based nanomembranes were discussed under surface coating and blending methods. Studies related to use of PVDF-based nanomembranes in adsorption, filtration, catalysis (oxidant activation, ozonation, Fenton process and photocatalysis) and membrane distillation have been elaborately discussed. Nanomaterials including metal compounds, metals, (synthetic/bio)polymers, metal organic frameworks, carbon materials and their composites were incorporated in PVDF membrane to enhance its performance. The advantages and limitations of incorporating nanomaterials in PVDF-based membranes have been highlighted. The influence of nanomaterials on the surface features, mechanical strength, hydrophilicity, crystallinity and catalytic ability of PVDF membrane was discussed. The conclusion of this literature review was given along with future research.Universidad Autónoma de Chil
Common Beans as a Source of Amino Acids and Cofactors for Collagen Biosynthesis
No full textCommon beans (Phaseolus vulgaris L.) are widely consumed in diets all over the world and have a significant impact on human health. Proteins, vitamins, minerals, phytochemicals, and other micro- and macronutrients are abundant in these legumes. On the other hand, collagens, the most important constituent of extracellular matrices, account for approximately 25–30 percent of the overall total protein composition within the human body. Hence, the presence of amino acids and other dietary components, including glycine, proline, and lysine, which are constituents of the primary structure of the protein, is required for collagen formation. In this particular context, protein quality is associated with the availability of macronutrients such as the essential amino acid lysine, which can be acquired from meals containing beans. Lysine plays a critical role in the process of post-translational modifications facilitated with enzymes lysyl hydroxylase and lysyl oxidase, which are directly involved in the synthesis and maturation of collagens. Furthermore, collagen biogenesis is influenced by the cellular redox state, which includes important minerals and bioactive chemicals such as iron, copper, and certain quinone cofactors. This study provides a novel perspective on the significant macro- and micronutrients present in Phaseolus vulgaris L., as well as explores the potential application of amino acids and cofactors derived from this legume in the production of collagens and bioavailability. The utilization of macro- and micronutrients obtained from Phaseolus vulgaris L. as a protein source, minerals, and natural bioactive compounds could optimize the capacity to promote the development and durability of collagen macromolecules within the human body. © 2023 by the authors.Vicerrectoría de Investigación y Doctorados de la Universidad San Sebastián, (VRID_APC23/24); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (11220738, 1212026); Agencia Nacional de Investigación y Desarrollo, ANID, (R20F0001)Universidad Autónoma de Chil
A Cross-Sectional Study to Measure Physical Activity with Accelerometry in ADHD Children according to Presentations
No full text(1) Background: Attention deficit hyperactivity disorder (ADHD) is a common mental disorder affecting 5–7% of school-aged children. Previous studies have looked at the effects of physical activity interventions on the symptoms of ADHD, although few have compared the motor behavior of children with ADHD versus those without. This exploratory study provides detailed information on the patterns and intensity of physical activity and sedentary behavior in children with ADHD as measured by Actigraph GT3X accelerometry, as well as the differences in physical activity in the different presentations of ADHD; (2) Methods: A cross-sectional design was used with a sample of 75 children, aged 6 to 12 years, with and without ADHD. The ADHD group had a previous diagnosis, determined by clinical assessment based on DSM-5 criteria; (3) Results: Physical activity levels were higher in children with ADHD compared to children without ADHD, but there was no difference in sedentary time between groups during weekdays or weekends. Physical activity decreased with age, with significant differences in the ADHD group, who exhibited more minutes of moderate Physical activity in 6–7 year-olds than 10–11 year-olds during weekdays and weekends; (4) Conclusions: Sedentary time increased by age in children without ADHD, and there was a decrease in moderate-intensity physical activity time in children with ADHD by age.Universidad Autónoma de Chil
Sexuality and affectivity after a grieving process for an antenatal death: a qualitative study of fathers' experiences
No full textThe loss of an infant at the prenatal stage is one of the most traumatic events parents can experience. Prenatal losses have several negative implications for parents' physical, psychological, and social well-being, including intimacy and sexuality. Fathers who suffer from this experience have to cope not only with their grief, but also with the physical and emotional suffering of their partners. The social context gives the father a masculine role of strength, insensitivity, and protection of the mother, with the result that his pain and grief become invisible. The objective of this study is to understand fathers' experience of affective-sexual relationships after a grieving process for an antenatal death; A qualitative study based on interviews with 11 fathers in Spain who have experienced an antenatal death was conducted. Data were analyzed with the help of ATLAS.ti software to discover emerging themes. 6 sub-themes were developed from the analysis, grouped into two main themes: the invisibility of grieving fathers and the relationships between the grieving parents are influenced by the death of their infants. The sexuality of fathers who suffer an antenatal death is altered. Gender stereotypes and the lack of social and professional awareness make their grief invisible. Fathers need to express their emotions to cope with their own grief and break the stereotypical gendered bereavement. In most cases, the couple's relationship is altered, from a close union to a more distant relationship, in addition to a decrease in sexual desire and arousal. However, other fathers experienced greater closeness and intimacy in the couple. A communication based on sincerity, exposing their own grief, feelings, emotions and needs could help the couple's relationship.Research Group Health Sciences CTS-451, from the University of AlmeriaUniversidad Autónoma de Chil
Long Non-Coding RNAs (lncRNAs) as Regulators of the PI3K/AKT/mTOR Pathway in Gastric Carcinoma
No full textGastric cancer (GC) represents ~10% of the global cancer-related deaths, increasingly affecting the younger population in active stages of life. The high mortality of GC is due to late diagnosis, the presence of metastasis and drug resistance development. Additionally, current clinical markers do not guide the patient management adequately, thereby new and more reliable biomarkers and therapeutic targets are still needed for this disease. RNA-seq technology has allowed the discovery of new types of RNA transcripts including long non-coding RNAs (lncRNAs), which are able to regulate the gene/protein expression of many signaling pathways (e.g., the PI3K/AKT/mTOR pathway) in cancer cells by diverse molecular mechanisms. In addition, these lncRNAs might also be proposed as promising diagnostic or prognostic biomarkers or as potential therapeutic targets in GC. This review describes important topics about some lncRNAs that have been described as regulators of the PI3K/AKT/mTOR signaling pathway, and hence, their potential oncogenic role in the development of this malignancy. © 2023 by the authors.DIUAV, (03-2022); DIUFRO, (DI20-0128, DI20-0160); Horizon 2020 Framework Programme, H2020, (825510); Universidad Autónoma de Coahuila, UAdeC; European Research Council, ERC; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1210440, 1221345, 3210237, 3210629); Universidad de La Frontera, UFRO; Fondo de Fomento al Desarrollo Científico y Tecnológico, FONDEF, (ID21I10027); Instituto Milenio en Inmunología e Inmunoterapia, MIII, (ICN2021_045); Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias, FONDAP, (152220002); Agencia Nacional de Investigación y Desarrollo, ANIDUniversidad Autónoma de Chil
Bacillus litorisediminis sp. nov., a Thermophilic Bacterium Isolated from Mangrove Sediment
No full textTwo aerobic, Gram-staining-positive, rod-shaped, endospore-forming, thermophilic bacterial strains, designated FJAT-47801T and FJAT-47835, were isolated from the sediment collected from Zhangjiang Estuary Mangrove National Nature Reserve in Fujian Province, China. Growth was observed at 25–55 °C (optimum, 50 °C) and pH 7.0–9.0 (optimum, pH 7.0), with up to 4.0% (w/v) NaCl (optimum, without NaCl). Strains FJAT-47801T and FJAT-47835 showed the highest 16S rRNA gene sequence similarity to Bacillus oleivorans (98.5%). The 16S rRNA gene sequence similarity between FJAT-47801T and FJAT-47835 was 99.9% indicating they were the same species. Phylogenetic (based on 16S rRNA gene sequences) and phylogenomic (based on 120 conserved bacterial single-copy genes) trees showed that strains FJAT-47801T and FJAT-47835 should be affiliated to the genus Bacillus. The of menaquinone of strain FJAT-47801T was MK-7. The major fatty acids of strain FJAT-47801T were iso-C15:0, anteiso-C15:0, iso-C17:0, and C16:0. The major polar lipids strain FJAT-47801T were phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and phosphatidylglycerol (PG). The genomic DNA G+C content of strain FJAT-47801T was 39.3%. The average nucleotide identity (84.3%) and the digital DNA–DNA hybridization value (28.1%) between strain FJAT-47801T and B. oleivorans CCTCC AB 2013353T were below the cut-off level for species delineation. Based on the above results, strain FJAT-47801T represents a novel species of the genus Bacillus, for which the name Bacillus litorisediminis sp. nov., is proposed. The type strain is FJAT-47801T (=GDMCC 1.2712T = JCM 34875T).Universidad Autónoma de Chil
Desalination effects on macroalgae (part b): Transplantation experiments at brine-impacted sites with Dictyota spp. from the Pacific Ocean and Mediterranean Sea
No full textDesalination residual brines are mostly discharged to marine environments, which can produce osmotic stress on sensitive benthic organisms. In this investigation, we performed transplantation experiments nearby desalination plants using two brown macroalgae species from a cosmopolitan genus: Dictyota kunthii (Chile) and Dictyota dichotoma (Spain). Parameters related to photosynthetic activity and oxidative stress were evaluated at 3 and 7 days for D. kunthii, and 3 and 6 days for D. dichotoma; each at 2 different impacted sites and 1 control. We observed that brine exposition at both impacted sites in Chile generated a marked stress response on D. kunthii, reflected in a decrease of primary productivity (ETRmax), light requirement (EkETR), and an excessive thermal dissipation (NPQmax), especially at 7 days. In D. dichotoma, similar impaired photosynthetic activity was recorded but only at the highest brine influence site during day 3. Regarding oxidative stress, both species displayed high levels of H2O2 when exposed to brine-influenced sites. Although in D. kunthii H2O2 content together with lipid peroxidation was higher after 3 days, these returned to baseline values towards day 7; instead, D. dichotoma H2O2 levels increased only at day 6. This easy and practical approach has proven to provide valuable data to address potential impacts of brine discharges at global scale coastal ecosystems. Copyright © 2023 Muñoz, Rodríguez-Rojas, Celis-Plá, López-Marras, Blanco-Murillo, Sola, Lavergne, Valenzuela, Orrego, Sánchez-Lizaso and Sáez.ANID FONDECYT, (3180394); European Commission Marie Skłodowska-Curie Actions, (888415); Fundación Carolina of Spain; Universidad de Playa Ancha, UPLA; Agencia Nacional de Investigación y Desarrollo, ANID, (INID210013)Universidad Autónoma de Chil
Agricultural impacts on lowland tropical streams detected through leaf litter decomposition
No full textStream ecosystems are highly vulnerable to changes in land use and vegetation in their catchments for two reasons: firstly, they receive inputs of nutrients, contaminants and sediments through runoff; and secondly, terrestrial leaf litter is the major basal resource supporting their food webs. Leaf litter decomposition by microorganisms and detritivores is thus a key stream ecosystem process, and a valuable functional indicator of impacts associated to agriculture and other alterations of human origin. Here, we investigated the joint effects of land use changes associated to agriculture (low, medium and high intervention areas: LI, MI and HI, respectively) in a tropical lowland catchment in Panama, through a decomposition experiment using three leaf litter types differing in nativeness (Ficus insipida, native to the study area; Alnus acuminata, native to Panama but not present in the study area; and Musa balbisiana, exotic to Panama). Lowland tropical areas are often poor in litter-consuming detritivores, and we accordingly observed a high contribution of microorganisms to total decomposition (>60% on average). However, only in the presence of detritivores, decomposition of Alnus discriminated among different degrees of agricultural intervention, being higher at the LI area. Leaf litter of the native Ficus showed higher microbial decomposition than the other types, possibly in relation to a home-field advantage effect. Despite the scarcity of detritivores in tropical lowland streams compared to tropical highland or temperate streams, our study indicates that their activity reflects impacts of land use change on these streams and they should therefore be included in assessments of anthropogenic impacts. © 2023 The Author(s)MIDA; Ministry of Agricultural Development; University of Panama, (CUFI-2021-EG-CNET-001); Consejería de Economía y Hacienda, (019910.001, 102720201.704); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1231551); Eusko Jaurlaritza, (IT1471-22); Ministry of Environment, MOE, (101030118); Secretaría Nacional de Ciencia, Tecnología e Innovación, SENACYT, (270–2018-1011); Sistema Nacional de Investigadores, SNI, (88–2022); Sistema Nacional de Investigación, Secretaría Nacional de Ciencia, Tecnología e Innovación, SNI, SENACYT; Agencia Nacional de Investigación y Desarrollo, ANID, (ATE220060)Universidad Autónoma de Chil
Effect of exercise on bone health in children and adolescents with cancer during and after oncological treatment: A systematic review and meta-analysis
No full textBackground: Although regular physical activity and exercise programs might improve bone health caused by oncological treatment and the disease itself, it remains unknown the pooled effect of exercise interventions following frequency, intensity, time and type prescriptions. Objective: This systematic review and meta-analysis aimed to synthesise evidence regarding the effectiveness of exercise interventions on bone health in children and adolescents with cancer during and after oncological treatment. Methods: A systematic search was conducted in the MEDLINE (via PubMed), Web of Science and Scopus databases from November 2021 to January 2022. Randomised controlled trials (RCTs) and non-RCTs reporting pre-post changes of the effectiveness of exercise interventions on DXA-measured bone parameters in young population (1–19 years) during or after oncological treatment were included. Pooled (ESs) and 95% confidence intervals (95%CIs) were calculated. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Results: A total of eight trials with 341 participants were included. The meta-analyses did not reveal a statistically significant increase in whole body areal bone mineral density (ES = 0.10; 95%CI: −0.14, 0.34), lumbar spine (ES = 0.03; 95%CI: −0.21, 0.26) or femoral neck (ES = 0.10; 95%CI: −0.37, 0.56). Similarly, during the oncological treatment phase the ES was 0.04 (95%CI: −0.17, 0.25) and after the ES was 0.07 (95%CI: −0.20, 0.33). Conclusion: To date, exercise interventions have been inappropriate and therefore, ineffective to illustrate any beneficial effect on bone health in children and adolescents with cancer during and after oncological treatment. Systematic Review Registration: PROSPERO registration number: CRD42022310876. Copyright © 2023 Marmol-Perez, Ubago-Guisado, Rodriguez-Solana, Gil-Cosano, Martinez-Vizcaino, Cavero-Redondo, Ruiz and Gracia-Marco.Ministerio de Ciencia e Innovación and Unión Europea; Ministerio de Universidades y la Unión Europea; Nutrition and Health; UCEENS; University of Granada Plan Propio de Investigación; 'la Caixa' Foundation, (LCF/BQ/PR19/11700007); Ministerio de Educación, Cultura y Deporte, MECD; Instituto de Salud Carlos III, ISCIII; Ministerio de Ciencia e Innovación, MICINN, (PID2020-117302RA-I00); European Regional Development Fund, ERDF, (FPU20/05530); Centro de Investigación Biomédica en Red-Fisiopatología de la Obesidad y Nutrición, CIBEROBN; Centro de Investigación Biomédica en Red de Cáncer, CIBERONC, (CB22/03/00058)Universidad Autónoma de Chil