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Unravelling large-scale patterns and drivers of biodiversity in dry rivers
No full textPublisher Copyright: © The Author(s) 2024.More than half of the world’s rivers dry up periodically, but our understanding of the biological communities in dry riverbeds remains limited. Specifically, the roles of dispersal, environmental filtering and biotic interactions in driving biodiversity in dry rivers are poorly understood. Here, we conduct a large-scale coordinated survey of patterns and drivers of biodiversity in dry riverbeds. We focus on eight major taxa, including microorganisms, invertebrates and plants: Algae, Archaea, Bacteria, Fungi, Protozoa, Arthropods, Nematodes and Streptophyta. We use environmental DNA metabarcoding to assess biodiversity in dry sediments collected over a 1-year period from 84 non-perennial rivers across 19 countries on four continents. Both direct factors, such as nutrient and carbon availability, and indirect factors such as climate influence the local biodiversity of most taxa. Limited resource availability and prolonged dry phases favor oligotrophic microbial taxa. Co-variation among taxa, particularly Bacteria, Fungi, Algae and Protozoa, explain more spatial variation in community composition than dispersal or environmental gradients. This finding suggests that biotic interactions or unmeasured ecological and evolutionary factors may strongly influence communities during dry phases, altering biodiversity responses to global changes
Manual para la confección ficha clínico integral del nIño I y II : Guía practica para confección ficha clínico
No full textIntroducción : La ficha clínica que utilizamos en Odontopediatría es un documento legal que contiene la historia clínica de un paciente, información personal, el motivo de consulta, y constituye el registro del diagnóstico y procedimientos que recibe a lo largo del tratamiento el paciente. Mediante la ficha clínica, el alumno podrá indagar sobre la historia médica familiar y antecedentes del niño, que le permitirá conocer como el período gestacional, el trabajo de parto, tipo de parto y posterior desarrollo. Además de conocer los aspectos psicosociales y el entorno familiar donde se desarrolla el niño. El proceso de confección de la ficha clínica le permitirá al estudiante adquirir
habilidades y destrezas para la adecuada categorización del niño en cuanto a su desarrollo físico, psicológico y evaluar el riesgo social, biológico y cariogénico. Mediante la correcta indagación de todos los ítems expuestos, el alumno podrá realizar un correcto diagnóstico, generar un plan de tratamiento personalizado, y la derivación y/o interconsulta oportuna cuando el caso así lo requiera.
Este Manual pretende entregar al estudiante la información básica con la cuál debe ser confeccionada la Ficha Clínica de la Cátedra de Clínica Integral del Niño, Universidad San Sebastián, Sede Santiag
Augmenting the Stability of Automatic Voltage Regulators through Sophisticated Fractional-Order Controllers
No full textPublisher Copyright: © 2024 by the authors.The transition from traditional to renewable energy sources is a critical issue in current energy-generation systems, which aims to address climate change and the increased demand for energy. This shift, however, imposes additional burdens on control systems to maintain power system stability and quality within predefined limits. Addressing these challenges, this paper proposes an innovative Modified Hybrid Fractional-Order (MHFO) automatic voltage regulator (AVR) equipped with a fractional-order tilt integral and proportional derivative with a filter plus a second-order derivative with a filter FOTI-PDND2N2 controller. This advanced controller combines the benefits of a (FOTI) controller, known for enhancing dynamic performance and steady-state response, with a (PDND2N2) controller to improve system robustness and adaptability. The proposed MHFO controller stands out with its nine tunable parameters, providing more extensive control options than the conventional three-parameter PID controller and the five-parameter FOPID controller. Furthermore, a recent optimization approach using a growth optimizer (GO) has been formulated and applied to optimally adjust the MHFO controller’s parameters simultaneously. The performance of the proposed AVR based on the MHFO-GO controller is scrutinized by contrasting it with various established and developed optimization algorithms. The comparative study shows that the AVR based on the MHFO-GO controller surpasses other AVR controllers from the stability, robustness, and dynamic response speed points of view
The impact of lockdown, fatigue, and social interaction on highway demand during the COVID-19 pandemic : The case of Santiago, Chile
No full textPublisher Copyright: © 2023 Elsevier LtdThe COVID-19 pandemic, as well as the government measures to curb its spread, have significantly affected mobility. Various studies have investigated behavioral changes across different transport modes accounting for sociodemographic variables, yet the focus has predominantly been on public transportation. This article addresses this gap by quantifying the impact of mobility restrictions on an urban highway in Santiago, Chile. To do so, we develop several econometric models based on panel data, which enable us to assess control measures’ effects while accounting for their spatial heterogeneity. Our computational experiments demonstrate that traffic reductions were more significant among higher-income drivers (1% reduction per each 100,000 pesos increase). Conversely, municipalities with a higher proportion of elderly residents saw less drastic decreases in traffic. Regarding the effectiveness of control measures, we confirm that the lockdown is affected by fatigue and social interaction. The fatigue implies that users do not fulfill the lockdown as time passes, reducing the effect of quarantines by about 50% during October, 2020. The social interaction effect suggests the lockdown is less effective when not all city's municipalities are restricted to travel, which might be an argument against dynamic or partial lockdowns
Preparación y caracterización de nanopartículas de lignina desde plantas de diferente origen
No full textPublisher Copyright: © 2024 by the authors.This article presents new research on producing lignin nanoparticles (LNPs) using the antisolvent nanoprecipitation method. Acetone (90%) served as the lignin solvent and water (100%) as the antisolvent, using five types of lignins from various sources. Comprehensive characterization techniques, including NMR, GPC, FTIR, TEM, and DLS, were employed to assess both lignin and LNP properties. The antioxidant activity of the LNPs was evaluated as well. The results demonstrated the successful formation of spherical nanoparticles below 100 nm with initial lignin concentrations of 1 and 2%w/v. The study highlighted the crucial role of lignin purity in LNP formation and colloidal stability, noting that residual carbohydrates adversely affect efficiency. This method offers a straightforward, environmentally friendly approach using cost-effective solvents, applicable to diverse lignin sources. The innovation of this study lies in its demonstration of a cost-effective and eco-friendly method to produce stable, nanometric-sized spherical LNPs. These LNPs have significant potential as reinforcement materials due to their reinforcing capability, hydrophilicity, and UV absorption. This work underscores the importance of starting material purity for optimizing the process and achieving the desired nanometric dimensions, marking a pioneering advancement in lignin-based nanomaterials
How authentic are assessments in vocational education?An analysis from Chilean teachers, students, and examinations.
No full textPublisher Copyright: Copyright © 2024 Villarroel, Melipillán, Santana and Aguirre.Authentic assessment promotes professional skills, bridging the gap between academic knowledge and real-world scenarios. Given the challenges faced by vocational education in Chile, there is a keen interest in assessment methods within both secondary schools and higher education institutions. A non-experimental quantitative design was employed. The methodological approach used was a cross-sectional survey. The study’s sample included 244 students, 37 teachers, and a compilation of 905 questions sourced from written examinations. The findings reveal certain disparities in perspectives between teachers, students, and the examinations reviewed. On one hand, secondary vocational education teachers perceive the quality of assessments to exceed those of their counterparts in higher vocational education. Conversely, students in higher vocational education express a heightened sense of depth and engagement in their learning compared to their secondary vocational education peers. Upon examination of the assessments, it becomes evident that while written examinations are more prevalent in secondary vocational schools, these often involve open-ended and analytical inquiries. In contrast, higher vocational education institutions predominantly rely on closed-response questions that lean toward rote memorization. However, when these questions are open-ended, they are more oriented toward the transfer of knowledge compared to the secondary vocational education level. The level of realism is more pronounced in higher vocational education than in secondary vocational education. Both educational tiers exhibit gaps in attaining the principles of authentic assessment
Precordial catch syndrome : literature review
No full textPublisher Copyright: © 2024Resumen Introducción El dolor torácico es un motivo de consulta frecuente en la práctica clínica. Dentro de sus causas, el síndrome de pinzamiento precordial parece ser una de las principales, pero poco conocidas. Métodos Se realizó una revisión narrativa de literatura y se amplió la búsqueda mediante el método bola de nieve para encontrar artículos relevantes. Resultados Se encontraron 16 artículos, publicados únicamente en inglés. El síndrome de pinzamiento precordial se caracteriza por ser un cuadro de dolor torácico punzante de breve duración, que agrava con la respiración. No se necesita de exámenes complementarios para el diagnóstico y el tratamiento se centra en educar al paciente. Su etiología aún no está esclarecida. Conclusión El síndrome de pinzamiento precordial es un cuadro frecuente de dolor, especialmente en población joven. Futuros estudios pueden ser de ayuda para dilucidar la incidencia, etiología y factores de riesgo, además de darle relevancia a un cuadro que es poco conocido por la comunidad médica
"Non-religion" and "liminal religiosity"Research Proposals for the Study of Institutional Religious Disaffection in Latin America
No full textPublisher Copyright: © 2024 Universidad Compultense Madrid. All rights reserved.The following article aims to present two analytical tools for understanding the process of disaffection from religious institutions in the context of Latin American modernity: the concept of "non-religion" and a strategy focused on the liminality of the religious ('liminal religiosity'). The main argument holds that religious disaffection, understood through the growth of the unaffiliated population and other associated phenomena, implies the existence of a heterogeneous space rather than a residual and negative category. To achieve this, and through a methodology of literature review, a critical examination is made of the main theoretical nuclei of the social sciences regarding the religious phenomenon, identifying some underlying patterns such as a normative conception of secularization and the predominance of a Western modern narrative that would hinder problematizing new trends in regional religious change. It is concluded that these proposals may serve as valuable tools insofar as they are complemented by less restrictive models, grounded in more versatile theoretical and methodological frameworks, and an open, minimalist understanding of religion that is attuned to the uniqueness of Latin American modernity.El siguiente artículo tiene como objetivo presentar dos herramientas analíticas para la comprensión del proceso de desafección de las instituciones religiosas en el contexto de la modernidad latinoamericana: el concepto de ‘no-religión’ y una estrategia centrada en el carácter de liminalidad de lo religioso (‘religiosidad liminal’). El principal argumento sostiene que la desafección religiosa, entendida desde el crecimiento de la población no-afiliada y otros fenómenos asociados suponen la existencia de un espacio heterogéneo y no una categoría residual y negativa. Para ello y mediante una metodología de revisión bibliográfica, se realiza un examen crítico de los principales núcleos teóricos de las ciencias sociales sobre el fenómeno religioso identificando algunos patrones subyacentes tales como una concepción normativa de la secularización y el predominio de una narrativa moderna occidental que impedirían problematizar nuevas tendencias en el cambio religioso regional. Se concluye que estas propuestas pueden ser valiosas herramientas en la medida en que se complementen con modelos menos restrictivos a partir de dispositivos teórico-metodológicos más versátiles y una comprensión de lo religioso minimalista y situada en singularidad de la modernidad latinoamericana
Musculoskeletal pain and upper quadrant disability in stringed-instrument studentsA cross-sectional pilot study
No full textPublisher Copyright: © 2024 Federacion Espanola de Docentes de Educacion Fisica. All rights reserved.Background: Musculoskeletal pain (MSP) is prevalent in musicians and is mainly located in the upper quadrant, affecting functionality. Repetitive movements, type of instrument, age, and sex influence this behavior, among other factors. Although the evidence is limited, it seems that string players are among those who most frequently report pain and disability of musculoskeletal origin. Objective: To characterize MSP and the level of upper quadrant disability associated with stringed instrument playing in conservatory students. Methods: In this cross-sectional observational pilot study, six self-reported assessment instruments were applied to 14 string students (8 males and six females) of different instruments (violin, viola, classical guitar, cello and double bass): Quick Dash Global (QDG) and High Performance/Musicians (QDL), Neck Disability Index (NDI), Chronic Pain Grading Scale (EGDC), the Neuropathic Pain Questionnaire (abbreviated DN4) and the Body Map of Pain (body chart). Results: 100% of the sample presented MSP at the time of the evaluation, mostly of low intensity, being in 21.42% of the cases of chronic and disseminated character. Neuropathic pain was present in 64.28% of cases. General functionality measured with EGDC was affected in 71.42% of the individuals. Upper limb functionality presented a mean QDG of 16.4 ±15.63 and a mean QDL of 32.11 ±16.78, while at the cervical level, 64.28% presented mild to moderate disability measured with NDI. Conclusion: DME and upper quadrant disability are frequent conditions in chordophone student musicians. Future studies should deepen the causes and investigate efficient strategies to prevent these conditions throughout their training process
Socio-spatial analysis of migrant school students according to Bourdieu's capitals in Santiago de Chile (2017–2020)
No full textChile has experienced a substantial immigration boom in the last 10 years. The urban areas of this nation present high levels of residential segregation, represented in its main city, Santiago. This article presents results of an exploratory analysis of the relationship between residential segregation, immigration rate by educational institutions and changes in school performance. Based on the generation of clusters characterized by cultural, social, economic and symbolic capital, an analysis of the changes in school performance in those schools that received the greatest number of migrants is generated