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Regulation of a novel Acidithiobacillus caldus gene cluster involved in metabolism of reduced inorganic sulfur compounds
No full textINDEXACIÓN: WEB OF SCIENCE.Acidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regulation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR, rsrS, tetH, and doxD, coding for a transposase, a two-component response regulator (RsrR and RsrS), tetrathionate hydrolase, and DoxD, respectively. As shown by quantitative PCR, rsrR, tetH, and doxD are upregulated to different degrees in the presence of tetrathionate. Western blot analysis also indicates upregulation of TetH in the presence of tetrathionate, thiosulfate, and pyrite. The tetH cluster is predicted to have two promoters, both of which are functional in Escherichia coli and one of which was mapped by primer extension. A pyrrolo-quinoline quinone binding domain in TetH was predicted by bioinformatic analysis, and the presence of an o-quinone moiety was experimentally verified, suggesting a mechanism for tetrathionate oxidation.https://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC2168230&blobtype=pd
Exploring lower limb muscle activity and performance variations during instrumented Sit-to-Stand-to-Sit in sedentary individuals: Influence of limb dominance and testing modalities
No full textTEXTO COMPLETO EN INGLÉSPurpose
to explore lower limb muscle activity concerning limb dominance, as well as variations in force and power during the standing up and sitting down phases of the instrumented sit-to-stand-to-sit test in sedentary individuals, across isokinetic and isotonic modalities.
Methods
33 sedentary individuals underwent testing using a functional electromechanical dynamometer in both isokinetic and isotonic modes, accompanied by surface electromyography.
Results
In the isokinetic mode, the non-dominant gastrocnemius medialis and vastus medialis exhibited significantly (p < 0.05) higher muscle activity values during the standing up and sitting down phase compared to dominant counterparts. In the isotonic mode standing up phase, significant differences in muscle activity were noted for non-dominant gastrocnemius medialis, vastus medialis, and biceps femoris compared to their dominant counterparts. The sitting down phase in isotonic mode showed higher muscle activity for non-dominant vastus medialis compared to dominant vastus medialis. Regard to performance outcomes, significantly lower (p < 0.0001) values were observed for standing up (12.7 ± 5.1 N/kg) compared to sitting down (15.9 ± 6.1 N/kg) peak force, as well as for standing up (18.7 ± 7.8 W/kg) compared to sitting down (25.9 ± 9.7 W/kg) peak power in isokinetic mode. In isotonic mode, lower values were found for sitting down (6.5 (6.3–7.1) N/kg) compared to standing up (7.8 (7.3–8.9) N/kg) peak force and for sitting down (18.5 (13.2–21.7) W/kg) compared to standing up (33.7 (22.8–41.6) W/kg) peak power.
Conclusions
Limb dominance influences lower-limb muscle activity during the instrumented sit-to-stand-to-sit test, and the choice of testing mode (isokinetic or isotonic) affects muscle engagement and performance outcomes.https://www-sciencedirect-com.recursosbiblioteca.unab.cl/science/article/pii/S003193842400163
Framing evidence synthesis production with the lens of sustainable knowledge
No full textIndexación: Scopus.Systematic reviews are widely recognized as the cornerstone of evidence-based health decision-making. Individual studies are synthesized into coherent summaries, providing clarity amid the complexity of modern scientific research. However, the systematic review model is facing a crisis. The rapid increase in the number of reviews has paradoxically undermined their utility, with many becoming outdated, redundant, or of low quality. Despite methodological advancements and the introduction of rapid and living reviews, the evidence ecosystem remains fragmented and inefficient. In this paper, it is argued that current reform efforts fall short because the crisis is not addressed holistically, and the concept of “sustainable knowledge” is proposed to frame evidence synthesis with the lens of sustainability.Lessons learned during the COVID-19 pandemic and emerging innovations are drawn upon to reframe the problem as systemic, calling for a reconsideration of the entire lifecycle of systematic reviews, including their creation, updating, and application in practice. Stronger networks of collaboration are encouraged, alongside careful use of automation and artificial intelligence where genuine value is added. Academic incentives are suggested to be reshaped so that quality and relevance are prioritized over the sheer number of publications. It is proposed that by adopting sustainability as a guiding principle, systematic reviews can better fulfill their purpose of providing timely, high-quality, and actionable evidence for health decision-making. © 2025 The Author(s).https://www.sciencedirect.com/science/article/pii/S0895435625003609?pes=vor&utm_source=scopus&getft_integrator=scopusS
Impact of a Before-School Physical Activity Program on Children's Subjective Well-Being: Secondary Findings From the Active-Start Study
No full textIndexación: Scopus.Objective The aim of the study was to test a before-school physical activity intervention (Active-Start) on subjective well-being in socioeconomically disadvantaged Chilean children. Method The Active-Start intervention was a randomized controlled trial involving 170 children aged 8 to 10 from 3 highly vulnerable public schools in Santiago (Chile). The physical activity intervention was delivered daily, before starting the first school-class (8:00–8:30 a.m.) for 8 weeks. Subjective well-being was assessed using validated instruments: the CUBE scale for life satisfaction and a 10-item affect scale for positive and negative emotions. The analyses used were generalized linear mixed models. Results The intervention significantly increased positive emotions in boys (B = 0.56, 95% confidence intervals [CI] 0.13 to 0.99, P = .011) and girls (B = 0.25, 95% CI 0.02 to 0.48, P = .044). Boys also showed an improvement in overall subjective well-being (z-score: B = 1.05, 95% CI 0.05 to 2.15, P = .041). Specifically, boys reported higher levels of happiness (B = 0.58, 95% CI 0.14 to 1.02, P = .031), contentment (B = 0.69, 95% CI 0.16 to 1.22, P = .012), and fun (B = 0.89, 95% CI 0.31 to 1.47, P = .003). In contrast, changes in life satisfaction and negative emotions were not significant for either sex. Conclusions Our findings suggest that engaging in morning physical activity before starting classes increases positive emotions (such as happiness, contentment, and fun) in children from socioeconomically disadvantaged backgrounds, particularly among boys. This improvement in emotional well-being could enhance their mood and readiness for learning. © 2025 Academic Pediatric Association.https://www.sciencedirect.com/science/article/pii/S1876285925003766?pes=vor&utm_source=scopus&getft_integrator=scopusFunding text
This study was funded by the Vicerrector\u00EDa de Investigaci\u00F3n, Desarrollo e Innovaci\u00F3n (Proyectos Basales) of the Universidad de Santiago de Chile (Chile), Grant number 051641ZR_DAS. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Open access funding was provided by Universidad P\u00FAblica de Navarra.S
High efficiency veto hadron calorimeter in the NA64 experiment at CERN
No full textIndexación: ScopusNA64 is a fixed-target experiment at the CERN SPS designed to search for Light particle Dark Matter (LDM) candidates with masses in the sub-GeV range. During the 2016–2022 runs, the experiment obtained the world-leading constraints, leaving, however, part of the well-motivated region of parameter space suggested by benchmark LDM models still unexplored. To further improve sensitivity, as part of the upgrades to the setup of NA64 at the CERN SPS H4 beamline, a prototype veto hadron calorimeter (VHCAL) was installed in the downstream region of the experiment during the 2023 run. The VHCAL, made of Cu-Sc layers, was expected to be an efficient veto against upstream electroproduction of large-angle hadrons or photon–nuclear interactions, reducing the background from secondary particles escaping the detector acceptance. With the collected statistics of 4.4×1011 electrons on target (EOT), we demonstrate the effectiveness of this approach by rejecting this background by more than an order of magnitude. This result provides an essential input for designing a full-scale optimized VHCAL to continue running background-free during LHC Run 4, when we expect to collect 1013 EOT. Furthermore, this technique combined with improvements in the analysis enables us to decrease our missing energy threshold from 50GeV to 40GeV, thereby enhancing the signal sensitivity of NA64. © 2025 The AuthorsS
Economic evaluation: Impact on costs, time, and productivity of the incorporation of integrative digital pathology (IDP) in the anatomopathological analysis of breast cancer in a national reference public provider in Chile
No full textIndexación: Scopus.Introduction: The incidence of breast cancer has risen in Chile, along with the complexity of diagnosis. For accurate diagnosis, it is necessary to complement the morphology assessed with hematoxylin and eosin with additional techniques to evaluate specific tumor markers. Evaluating the impact on costs, time, and productivity of automated techniques integrated with digital pathology solutions is crucial. Objectives: To estimate the impact on costs, time, and productivity of incorporating the automation of the HER2 in situ hybridization technique combined with integrative digital pathology (IDP) in breast cancer diagnosis in a Chilean public provider versus a manual technique. Methods: This economic evaluation adopted a health economics multi-method approach. A decision model was developed to represent the current manual fluorescence in situ hybridization (FISH) scenario versus an automated dual in situ hybridization (DISH) plus IDP in breast cancer diagnosis. Business process management (BPM) methodology was applied for capturing working time and latencies, in combination with a time-driven activity-based costing (TDABC) methodology for estimating direct, total, and average cost (2023 USD) for both scenarios for the following vectors: Human resources, supplies, and equipment, sorted by pre-analytical, analytical, and post-analytical phases. Indirect costs (2023 USD) were also retrieved. Both BPM and TDABC served to estimate labor productivity. Results: In the baseline scenario based on manual FISH, the turnaround time (TAT) was estimated at 1259 min, at an average total cost of 231.08, considering direct and indirect costs for all phases; it also showed an average of 22.8 submitted reports per pathologist monthly. This represents a decrease of 13.02% in average total costs, an 83.86% decrease in TAT, and an average labor productivity increase of 11.29%. Conclusions: The incorporation of automated DISH plus IDP in the pathology department of this public provider has resulted in reductions in the time required to perform the in situ hybridization technique, a decrease in total costs, and increased productivity. Particular attention should be given to adopting new technologies to accelerate processing times and workflow. © 2024 The Authorshttps://www.sciencedirect.com/science/article/pii/S2153353924000567?pes=vor&utm_source=scopus&getft_integrator=scopu
Mathematics classroom explanation: a literature review
No full textIndexación: Scopus.Research on explanation in the teaching of mathematics at the secondary education level is crucial for improving understanding and the effective learning of mathematical concepts. This study focuses on analyzing empirical research that has addressed the explanation in the teaching of mathematics at the secondary level, published in the last five years in journals indexed in the Web of Science. Methodology: A systematic analysis is carried out, following the PRISMA methodology to ensure a systematic and reproducible analysis. Results: The findings highlight that research at the primary and secondary educational levels on mathematical explanation is scarce. Studies with teaching innovations predominate. Discussions: The need for ongoing training for teachers is discussed, emphasizing the importance of clear explanations tailored to the needs of the students to facilitate deep and enduring learning, as well as the practical implications of the study. Conclusions: This study underscores the opportunity to expand research in this field to enrich pedagogical practices and improve the teaching of mathematics at fundamental educational levels. © 2025, HISIN (History of Information Systems). All rights reserved.MAEC-AECIDhttps://www-scopus-com.recursosbiblioteca.unab.cl/record/display.uri?eid=2-s2.0-85213406898&origin=resultslist&sort=plf-f&src=s&sid=3fe8173caf0d5620793cce959c362559&sot=aff&sdt=cl&cluster=scosubtype%2C%22ar%22%2Ct&s=AF-ID%2860002636%29+AND+SUBJAREA%28ECON%29&sl=34&sessionSearchId=3fe8173caf0d5620793cce959c362559&relpos=12Gabriel Valdés-León es investigador postdoctoral en la Universidad de Las Palmas de Gran
Canaria a través de una beca Margarita Salas, financiada por los fondos NextGenerationEU
(2022-2024). Se doctoró en Estudios Lingüísticos en 2021 por la misma universidad, con una
tesis que obtuvo el premio extraordinario de doctorado. Es máster en Lingüística por la
Universidad de Santiago de Chile (2014) y máster en Lexicografía Hispánica impartido por la
Universidad de León en colaboración con la Real Academia Española (2017), financiado por
una beca de la Fundación Carolina. En 2018, recibió una beca de la Cooperación Española
MAEC-AECID por sus contribuciones a los proyectos de la Academia Chilena de la Lengua.
[email protected]
Immediate admission to the surgery hospital significantly optimises quality indicators in older patients with hip fractures: A before-and-after study
No full textIndexación: Scopus.Background: Hip fractures generate high biomedical, social, functional, organisational, and economic costs. There are various quality indicators to guide its management. One of them is surgery within 48–72 h. In Chilean public health system, this indicator has out-of-standard results. This situation could have organizational causes: after hip fracture diagnosis, many older patients are first referred to general hospitals, whilst waiting an orthopedic surgical bed. Objective: To evaluate the effects of a protocol of immediate-admission to the surgery hospital on organisational and economic indicators of hip-fractured older patients. Design: Before-and-after study, between 01/01/2017–09/30/2019; 12 months before and 21 months after implementation. Setting: Regional surgical hospital responsible for 87 % of the older population in its assigned territory, in the more aged region of Chile. Participants: Anonymised data of 902 hip-fractured older adults (≥ 60 years). Intervention: Implementation of a protocol that requires immediate admission to the surgical hospital of all older hip-fractured patients at the time of diagnosis. Measurements: Number of hip-fractured patients with no immediate admission, time to surgery, total in-hospital time, and economic costs. Normality tests (Kolmogorov-Smirnov), non-parametric tests (Chi-squared), Mann-Whitney and Kruskal-Wallis tests were performed. Measures of central tendency (medians and percentiles) were used. Results: After protocol there was a significant reduction in the proportion of patients referred to general hospitals in both, first and second year (pre=37,8 %; post 1 = 27,3 %; post 2 = 23,3 %, p = 0,000). Time to surgery was also significantly reduced (medians bed days pre=15, post 1 = 11, post 2 = 10, p = 0,000). Total in-hospital time decreased 21 % (3395 bed days), and there was also a significant decrease in costs from USD130,000 to USD35,000 (p = 0,000). Conclusion: Immediate admission to orthopedic surgical hospital of older adults with hip fractures significantly decreases inter-hospital transfers, time to surgery, total in-hospital time, and direct hospital costs. © 2025https://www.sciencedirect.com/science/article/pii/S2260134125000052?pes=vor&utm_source=scopus&getft_integrator=scopusS
Toward decorrelation of surface oxygen groups from metal dispersion effects in Pd/C hydrogenation catalysts
No full textIndexación: Scopus.Carbon-supported Pd-based catalysts have found wide applications in hydrogenation of specific functional groups. Surface modification of the support, via the introduction of oxygen functional groups, modulates the metal dispersion and the interaction of reactant(s) with the catalyst surface, consequently tuning its catalytic properties. However, it is difficult to decorrelate the effect of surface oxygen groups from that of the dispersion of the metallic phase. This study aims at decorrelating these effects on the catalytic performance for phenylacetylene hydrogenation by using preformed monodispersed Pd nanoparticles deposited on carbon supports presenting different densities of surface oxygen groups. X-ray photoelectron spectroscopy, temperature-programmed decomposition experiments and transmission electron microscopy were used to analyze the dispersion and oxidation state of Pd and the concentration of surface oxygen groups. The results reveal that such decorrelation is not an easy task, particularly since spillover of the nanoparticles' native capping ligand (oleylamine) occurs during Pd particle deposition. This phenomenon, which depends on the density of oxygen functional groups and the size of Pd particles, impacts the Pd(0)/Pd2+ ratio and the surface Pd/N atomic ratio. These two last parameters, which seem to be interconnected, significantly impact the catalytic performance. © 2025 The Royal Society of Chemistryhttps://pubs.rsc.org/en/content/articlelanding/2025/cy/d4cy01562bThis work was supported by ECOS Sud - ANID (project ECOS no. C21E03) and PROGRAMA DE COOPERACI\u00D3N CIENT\u00CDFICA ECOS-ANID 210036. Edgardo Leal thanks Grant ANID 242230083. The authors acknowledge Fondequip EQM160070 for TPD analysis.S
Circuito de ejercicio funcional con tareas duales sobre variables clínicas relacionados con la sarcopenia
No full textIndexación: Scopus.Introduction: Most of exercise interventions to prevent sarcopenia have focused on individuals with sarcopenia or pre-sarcopenia. The effect of functional exercise with dual task on clinical variables of sarcopenia, have not been studied previously. Objective: This study analyzed the effects of a functional exercise program with dual task compared to aerobic exercise on outcomes related to sarcopenia, in older adults without clinical suspicion of sarcopenia. Methodology: This was a nonrandomized controlled trial (Registration: RBR-2HJJ7G/UTN:U1111-1254-3147). Forty-eight older adults were allocated into two interventions: 1) functional exercise circuit (FEC) with dual-task and 2) aerobic exercise. Both interventions were conducted for 12 weeks, 3 times a week, 50 minutes each session. Clinical suspicion of sarcopenia was determined by the algorithm of the European Working Group on Sarcopenia in Older People. Measurements of fat-free mass, fat mass, calf circumference, handgrip strength, 5-repetition sit-to stand, 4-meter gait speed, six-minute walking test and oxidative stress blood biomarkers were assessed before and after both interventions. Analyzes were performed using the SPSS version 22.0 and JAPS version 0.16.1. Results: Fat-free mass (p=0.049) and calf circumference (p<0.001) increased, and fat mass (p=0.017) reduced after FEC (ES: 0.1-0.6). Both groups showed improvement in the 5-repetition sit-to stand, 4-meter gait speed, six-minute walking test (p< 0.05 for all). All antioxidant biomarkers increased after FEC (ES: 0.2-0.6; p< 0.05 for all). Conclusion: Our study showed that FEC with dual task training improved muscle mass, muscle strength, physical performance, and antioxidant capacity, which are important outcomes related to sarcopenia. © 2025 Federacion Espanola de Docentes de Educacion Fisica. All rights reservedhttps://revistaretos.org/index.php/retos/article/view/110528We would like to thank the community groups of older adults, the members of the Church Nossa Senhora do Rocio, and the professionals from the University Hospital from Londrina, PR, Brazil for all the support in this project. This study was financed in part by the Programa de Apoio \u00E0 Extens\u00E3o Universit\u00E1ria do Minist\u00E9rio da Educa\u00E7\u00E3o (PROEXT) and Coordena\u00E7\u00E3o de Aperfei\u00E7oamento de Pessoal de N\u00EDvel Superior - Brasil (CAPES). WSL and RPT received scholarships from CAPES, Brazil. VSP is supported by the Conselho Nacional de Desenvolvimento Cient\u00EDfico e Tecnol\u00F3gico (CNPq), Brazil.S