Repositorio Institucional UCSC (Univ. Católica de la Santísima Concepción)
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Temporal analysis of bilateral index in bench press with different loads in male handball players
Get PDFObjetivo: Describir el índice bilateral (BI) en press banca para analizar la facilitación y déficit bilateral con diferentes cargas utilizando un análisis de series temporales.
Método: Dieciocho jugadores de balonmano (22,1 ± 3,8 años; 84,5 ± 15,9 kg; 179,3 ± 7,6 cm e IMC 26,2 ± 4,1) realizaron press de banca utilizando dinamometría electromecánica funcional, de forma bilateral y unilateral, con miembro superior hábil e inhábil, utilizando cargas de 40%, 60% y 75% de la contracción isométrica máxima. Cien valores de fuerza durante la fase concéntrica se utilizaron para el cálculo de BI, se evaluó la tendencia mediante análisis gráfico y descriptivo de las series y se utilizó Dynamic Time Warping para reconocer patrones y agrupar aquellas de características similares.
Resultados: Existen periodos de facilitación y déficit que varían en duración y magnitud con las diferentes cargas estudiadas.
Conclusiones: Considerar las series temporales de fuerza en el tiempo durante el empuje del press de banca conducen a una interpretación diferente de BI a la obtenidas con Fmax. La agrupación de las series sugiere la existencia de un patrón predominante independiente de la carga con que se realice el ejercicio, donde ocurre BLF en la etapa final del ejercicio
Application of ecohydrological criteria for the management of fisheries in the middle Paraná River (Argentina) during extreme low water levels
No full textSince 2019, there has been a long‐duration low water event that has no previous records in the floodplain of the Paraná River. This event highlights the lack of backgrounds and a lack of information on the socio‐economic and ecohydrological impacts, as well as the difficulty of implementing relevant management measures to address this hydrological condition. This scenario has triggered several environmental and socio‐economic conflicts associated with fishing activity. However, a conventional fisheries management approach with merely hydrological criteria is still carried out. This decoupling between the hydrological reality and the intensity of the fishing activity poses a threat to fish resources. The objective of this study was to discuss the application of ecohydrological criteria to advance the understanding of fish assemblage responses to the dynamics of hydrological processes in order to apply it to the management of the Paraná River fisheries, particularly in scenarios of extraordinary low water levels. We conclude that available knowledge does not include a comprehension of the effects of prolonged low water level on commercial fish assemblage recruitment and structure during prolonged low water levels, and there is not enough knowledge to establish criteria to define the sustainable management of fishery resources
Supercharging metabolic health with Lycium barbarum L.: A review of the therapeutic potential of this functional food for managing metabolic syndrome
Get PDFMetabolic syndrome (MetS) is a common disorder involving a cluster of metabolic abnormalities, such as abdominal obesity, hypertension, dyslipidemia, insulin resistance, and atherogenic profile. MetS is characterized by an increase in oxidative stress and a chronic proinflammatory state, which are directly related to the development and progression of this pathology. It has been seen how a healthy lifestyle and good dietary practices are key to improving the different metabolic parameters and, therefore, play a fundamental role in reducing the risk of developing diabetes. The present review focuses on the research evidence related to the therapeutic properties of Lycium barbarum L. in MetS gathered in the last years. Several preclinical studies suggest that L. barbarum extracts are a good dietary supplement for the prevention of cardiovascular diseases in people with MetS. This compound has been used for years in traditional Chinese medicine for the treatment of atrophic gastritis, problems related to the lungs, kidneys, and liver, and as a supplement for eye health. In addition, different in vitro and in vivo studies have been carried out that support the properties attributed to metabolites derived from L. barbarum, such as polysaccharides that have been shown diverse biological activities. In conclusion, L. barbarum extracts have multiple benefits to increase general well‐being and immune function. However, there are a limited number of studies related to effect of L. barbarum in MetS, but they demonstrated effectiveness in the treatment of obesity, diabetes mellitus type 2, and prevention of diabetes mellitus type 2 complication
Effects of High-Intensity Interval Training on Blood Pressure Levels in Hypertensive Patients: A Systematic Review and Meta-Analysis of Randomized Clinical Trials
Get PDFObjective: This systematic review and meta-analysis aimed to (I) evaluate the evidence on the effects of high-intensity interval training (HIIT) on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in hypertensive patients; (II) determine whether HIIT impacts SBP and DBP differently; and (III) assess the clinical relevance of these effects. Methods: A comprehensive search was conducted across multiple electronic databases, resulting in the inclusion of seven randomized clinical trials in the meta-analysis. The outcomes were analyzed using random-effects models to compute mean differences (MD) and standardized mean differences (SMD) for SBP and DBP. Results: A small reduction in SBP was observed with HIIT interventions (MD −3.00; 95% CI −4.61 to −1.39; p < 0.0001; SMD −0.28; 95% CI −0.42 to −0.13; p = 0.0003). However, no statistically significant reductions were detected for DBP (MD −0.70; 95% CI −1.80 to 0.39; p = 0.21; SMD −0.07; 95% CI −0.22 to 0.08; p = 0.35). Despite demonstrating statistical significance for SBP, the effects did not reach clinical relevance. Conclusions: HIIT interventions yield small reductions in SBP, with minimal impact on DBP. These findings suggest limited clinical relevance in the management of hypertension. Further randomized controlled trials are necessary to standardize HIIT protocols, with specific emphasis on intensity control and manipulation, to better understand their potential role in hypertensive populations
Morphological impact of Perovskite-Structured Lanthanum CobaltOxide (LaCoO3) nanoflakes toward supercapacitor applications
No full textIn this study, perovskite-structured lanthanum cobalt oxide(LaCoO3/LCO) systems with particle and flake morphologies were developed using sol−gel and hydrothermal methods, respectively, in order to investigate their morphological structure-dependent properties for potential supercapacitor applications. The structural analysis confirms that both methods yield LaCoO3with improved crystalline properties. The energy storage performance of the developed materials is studied in a three-electrode configuration using a 1 MKOH electrolyte. The results indicated superior electrochemical performance for the LCO nanoflakes, exhibiting specific capacitances of ∼215 F g−1 at a scan rate of 5 mV s−1 and ∼136 F g−1 at a current density of 1 A g−1. In comparison, the LCO nanoparticles showed ∼119 F g−1 at a scan rate of 5 mV s−1 and ∼99F g−1 at a current density of 1 A g−1. This difference can be largely attributed to their respective morphologies, porous structures, and surface defects. Further, the nanoflakes demonstrated an exceptional capacitance retention of ∼97% even after 5000 charge−discharge cycles. The findings of this study suggest that the properties of perovskite LaCoO3 can be tuned by adjusting its morphology through various synthesis methods, making LaCoO3 a viable and robust system for energy storage applications
Tailoring cellulose-based hydrogels by phosphorylation of unbleached kraft pulps for adsorption applications
No full textIndustrialization and human activities have exacerbated water pollution, demanding effective pollutant removal methods. Bio-based hydrogels, with their high porosity and extensive surface area, hold promise for this purpose. Cellulose is a suitable biopolymer for gel fabrication; however, the adsorption capacity of unmodified raw cellulose fibers often falls short of performance expectations due to the lack of strong binding sites. Therefore, this study investigates how different cellulose fiber types, chemical treatments, and solvent systems influence hydrogel properties for adsorption applications. Hydrogels were prepared from phosphorylated and unphosphorylated unbleached kraft pulps (UKP) derived from eucalyptus and pine using NMMO and IL solvent systems. Phosphorylation increased the surface charge of UKP from ~ 0.05 to ~ 2.3 mmol/g. However, the surface charge of phosphorylated samples decreased to 0.5–0.72 mmol/g after coagulation into hydrogels. Hydrogels prepared from phosphorylated UKP exhibited superior properties compared to the unphosphorylated counterparts, including increased specific surface area (12–64 m2/g to 53–95 m2/g), swelling capacity (1930–2800% to 3400–4800%), and higher MB adsorption capacity (13–30 mg/g to 156–291 mg/g). When comparing solvent systems, the NMMO-based hydrogel showed enhanced surface area and pore characteristics, while the IL-based hydrogel exhibited increased MB adsorption capacity (291 mg/g vs. 233 mg/g). Although pine-derived hydrogels had lower MB adsorption than eucalyptus-derived ones (156 mg/g vs. 291 mg/g), both showed comparable adsorption performance for Cu2+ ions (~ 40 mg/g). Overall, the IL-derived hydrogel from phosphorylated eucalyptus UKP proved most effective for removing MB and Cu2+ from aqueous solutions. These findings contribute to advancing cellulose-based hydrogels for efficient adsorption in wastewater treatment
Vulnerability of physical infrastructure network components to damage from the 2015 Illapel Tsunami, Coquimbo, Chile
Get PDFThis study assesses physical infrastructure vulnerability for infrastructure network components exposed during the 2015 Illapel tsunami in Coquimbo, Chile. We analyse road and utility pole vulnerability to damage, based on interpolated and simulated tsunami hazard intensity (flow depth, flow velocity, hydrodynamic force and momentum flux) and network component characteristics. A Random Forest Model and Spearman’s Rank correlation test are applied to analyse variable importance and monotonic relationships, with respect to damage, between tsunami hazards and network component attributes. These models and tests reveal that flow depth correlates higher with damage, relative to flow velocity, hydrodynamic force and momentum flux. Scour (for roads and utility poles) and debris strikes (for utility poles) are strongly correlated with damage. A cumulative link model methodology is used to fit fragility curves. These fragility curves reveal that, in response to flow depth, Coquimbo roads have higher vulnerability than those analysed in previous tsunami event studies, while utility poles demonstrate lower vulnerability than with previous studies. Although we identify tsunami flow depth as the most important hydrodynamic hazard intensity metric, for causing road and utility pole damage, multiple characteristics correlate with damage and should also be considered when classifying infrastructure damage levels
Association of stair use with risk of major chronic diseases
Get PDFIntroduction: Physical inactivity is associated with a higher risk of chronic diseases. Regular stair use can contribute to increasing physical activity in the population. This study aimed to investigate the association between flights of stairs used daily at home and all-cause mortality and cause-specific incidence and mortality.
Methods: Of the 502,628 UK Biobank participants recruited between 2007 and 2010, 442,027 (mean age, 56§8 years) had available data and were included in the analyses conducted in 2023. Participants were categorized on the basis of flights of stairs climbed daily (1−5, 6−10, 11−15, >15). The disease-specific outcomes were cardiovascular disease, respiratory disease, cancer, type 2 diabetes, and all-cause dementia. Cox proportional hazard models, adjusted for sociodemographic, lifestyle, and health-related confounding factors, were used to analyze the associations between stair use frequency and health outcomes.
Results: Participants were followed up for a median of 10.9 years. Climbing stairs >15 times per day was associated with a lower risk of 8 of the 9 outcomes analyzed than not using stairs. The magnitude of association ranged from 3% (95% CI=0.94, 0.99) lower risk for all-cause cancer to 51% (95% CI=0.39, 0.60) lower risk of chronic obstructive pulmonary disease. Findings were similar for mortality outcomes, with the hazard ratios ranging from 0.82 (95% CI=0.77, 0.87) for all-cause cancer to 0.46 (95% CI=0.23, 0.92) for chronic obstructive pulmonary disease mortality.
Conclusions: Stair use was associated with a lower risk of all-cause mortality and cause-specific incidence and mortality independent of confounding factors, including adiposity and multimorbidity
Estratégias de busca de informações na Internet para formação de professores
Get PDFLas habilidades necesarias para seleccionar, evaluar y sintetizar información de múltiples fuentes en internet son esenciales para los estudiantes de educación superior. Este estudio se enfocó en investigar cómo los estudiantes de un programa de formación de profesores en Chile abordan problemas que requieren la búsqueda de información y si existen diferencias en su enfoque al realizar estas tareas. Se utilizó el Índice de Desempeño de Búsqueda para clasificar a los participantes en tres grupos según su eficacia y eficiencia en la obtención de resultados. A través de registros computacionales, se compararon los grupos en su proceso de búsqueda de respuestas. Los datos fueron recopilados mediante un software de monitoreo (SurveilStar) y analizados a través SSPS v. 21. Los resultados dan cuenta de las estrategias más y menos exitosas empleadas por los estudiantes en la búsqueda de información. Se observó que los buscadores más eficientes se enfocan en un conjunto reducido de palabras clave, lo que aumenta sus posibilidades de encontrar respuestas de manera más rápida y eficaz, reduciendo el tiempo de escritura. Este hallazgo concuerda con investigaciones previas que sugieren que la formulación de consultas más elaboradas conduce a búsquedas más exitosas. Estos resultados tienen implicaciones importantes para la enseñanza y el desarrollo de habilidades de búsqueda de información en estudiantes de educación superior en Chile
Hydrographic shifts in coastal waters reflect climate-driven changes in hydrological regimes across Northwestern Patagonia
Get PDFClimate-driven changes in freshwater inputs have been shown to afect the structure and function of coastal ecosystems. We evaluated changes in the infuence of river runof on coastal systems of Northwestern Patagonia (NWP) over recent decades (1993–2021) by combined analysis of long-term streamfow time series, hydrological simulation, satellite-derived and reanalysis data on sea surface conditions (temperature, turbidity, and salinity). Signifcant decreases in minimum streamfow across a zone spanning six major river basins were evident at weekly, monthly, and seasonal scales. These changes have been most pronounced in mixed-regime northern basins (e.g., Puelo River) but appear to be progressing southward to rivers characterised by a nival regime. In the adjacent two-layer inner sea, reduced freshwater input corresponds with a shallower halocline and increased surface temperatures across northern Patagonia. Our results underscore the rapidly evolving infuence of rivers on adjacent estuarine and coastal waters in NWP. We highlight the need for cross-ecosystem observation, forecasting, mitigation and adaptation strategies in a changing climate, together with corresponding adaptive basin management of systems that supply runof to the coastal marine waters