66 research outputs found
Mesh dependence analysis for simulating unsteady cavitation around a plane convex hydrofoil
The mesh significantly influences the quality of the numerical results in computational fluid dynamics (CFD) problems due to its correlation with turbulence models. In the present paper a structured mesh was generated using Gmsh and two semi-structured meshes were generated using snappyHexMesh to determine the suitable mesh distribution for simulating unsteady cavitation around a plane convex hydrofoil. The numerical simulation was conducted by using the software OpenFOAM with the k-¿ SST SAS turbulence model and the ZwartGerber-Belamri (ZGB) cavitation model. Besides, the experimental results obtained by the Laboratory for Hydraulic Machines of École Polytechnique Fédérale de Lausanne were used to validate the numerical results. The results showed that both structured and semi-structured meshes predicted the cavitation pattern and the maximum cavity length. The semi-structured mesh with suitable refinement reproduced in detail the dynamic behavior of unsteady cavitation, while the structured mesh efficiently reproduced the phenomenon.Peer ReviewedObjectius de Desenvolupament Sostenible::7 - Energia Assequible i No ContaminantPostprint (published version
Minocycline reduces mechanical allodynia and depressive-like behaviour in type-1 diabetes mellitus in the rat
A common and devastating complication of diabetes mellitus is painful diabetic neuropathy (PDN) that can be accompanied by emotional disorders such as depression. A few studies have suggested that minocycline that inhibits microglia may attenuate pain hypersensitivity in PDN. Moreover, a recent study reported that minocycline has an acute antidepressive-like effect in diabetic animals. Here we studied whether (i) prolonged minocycline treatment suppresses pain behaviour in PDN, (ii) the minocycline effect varies with submodality of pain, and (iii) the suppression of pain behaviour by prolonged minocycline treatment is associated with antidepressive-like effect. The experiments were performed in streptozotocin-induced rat model of type-1 diabetes. Pain behaviour was evoked by innocuous (monofilaments) and noxious (paw pressure) mechanical stimulation, innocuous cold (acetone drops) and noxious heat (radiant heat). Depression-like behaviour was assessed using forced swimming test. Minocycline treatment (daily 80 mg/kg per os) of three-week duration started four weeks after induction of diabetes. Diabetes induced mechanical allodynia and hyperalgesia, cold allodynia, heat hypoalgesia, and depression-like behaviour. Minocycline treatment significantly attenuated mechanical allodynia and depression-like behaviour, while it failed to produce significant changes in mechanical hyperalgesia, cold allodynia or heat hypoalgesia. The results indicate that prolonged per oral treatment with minocycline has a sustained mechanical antiallodynic and antidepressive-like effect in PDN. These results support the proposal that minocycline might provide a treatment option for attenuating sensory and comorbid emotional symptoms in chronic PDN. (C) 2017 Elsevier B.V. All rights reserved.Peer reviewe
Parametric study of a horizontal axis wind turbine with similar characteristics to those of the Villonaco wind power plant
[EN] The present paper focuses on the selection of parameters that maximize electrical energy production of a horizontal axis wind turbine using Python programming language. The study takes as reference turbines of Villonaco wind field in Ecuador. For this aim, the Blade Element Momentum (BEM) theory was implemented, to define rotor geometry and power curve. Furthermore, wind speeds were analyzed using the Weibull probability distribution and the most probable speed was 10.50 m/s. The results were compared with mean annual energy production of a Villonaco’s wind turbine to validate the model. Turbine height, rated wind speed and rotor radius were the selected parameters to determine the influence in generated energy. Individual increment in rotor radius and rated wind speed cause a significant increase in energy produced. While the increment in turbine’s height reduces energy generated by 0.88%.The authors gratefully acknowledge the financial support provided by Escuela Politécnica Nacional for the development of the project PII-DIM-2019-06Sánchez, S.; Hidalgo, V.; Velasco, M.; Puga, D.; López Jiménez, PA.; Pérez Sánchez, M. (2021). Parametric study of a horizontal axis wind turbine with similar characteristics to those of the Villonaco wind power plant. Journal of Applied Research in Technology & Engineering. 2(2):51-62. https://doi.org/10.4995/jarte.2021.15056OJS516222Adaramola, M. (2014). Wind turbine technology: Principles and design. Apple Academic Press, Inc. https://doi.org/10.1016/s0038-092x(97)82047-6Arconel. (2015). Ecuador posee un 51,78% de energía renovable. https://www.regulacionelectrica.gob.ec/ecuador-posee-un-5155-de-energia-renovable/%0ABakırcı, M., & Yılmaz, S. (2018). Theoretical and computational investigations of the optimal tip-speed ratio of horizontal-axis wind turbines. 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Informe de rendición de cuentas 2014 Unidad de Negocio GEN-SUR. https://www.celec.gob.ec/gensur/index.phpCorporación Eléctrica del Ecuador. (2016a). Central Eólica Villonaco genera el 152% de lo planificado CE-LEC EPGENSUR. https://www.celec.gob.ec/gensur/index.php/67-central-eolica-villonaco-genera-el-152-de-lo-planificadoCorporación Eléctrica del Ecuador. (2016b). Informe de rendición de cuentas 2015 Unidad de Negocio GENSUR. https://www.celec.gob.ec/gensur/index.phpCorporación Eléctrica del Ecuador. (2017). Informe de Rendición de Cuentas 2016 Unidad de Negocio GENSUR. https://www.celec.gob.ec/gensur/index.phpCorporación Eléctrica del Ecuador. (2018). Informe de rendición de cuentas 2017 Unidad de Negocio GENSUR. https://www.celec.gob.ec/gensur/index.phpCorporación Eléctrica del Ecuador. (2019a). Informe de rendición de cuentas 2018 Unidad de Negocio GENSUR. https://www.celec.gob.ec/gensur/index.phpCorporación Eléctrica del Ecuador. (2019b). 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Gender Justice In The Americas: A Transnational Dialogue On Sexuality, Violence, Reproduction, And Human Rights
Nivel de estrés y el desempeño laboral del personal de enfermería en el área de central de esterilización del Hospital Daniel Alcides Carrión Huancayo - 2023
La actual pesquisa tuvo como propósito establecer la correlación entre el nivel
de estrés y desempeño laboral del personal de enfermería en el ámbito de la
central de esterilización del Hospital Daniel Alcides Carrión Huancayo 2023. La
investigación se enmarcó en un enfoque cuantitativo, con un diseño descriptivo
y correlacional no experimental, y se aplicó el método hipotético deductivo.
Para la recopilación de datos, se utilizó el primer cuestionario, con 21 ítems
para evaluar el nivel de tensión y 31 ítems para evaluar el rendimiento
ocupacional. Estos cuestionarios se administraron a 30 profesionales de
enfermería (técnicos y licenciados). Por otro lado, los resultados de la
investigación indicaron que, según el análisis de datos a través de la prueba
estadística Rho de Superman, se pudo validar la hipótesis alternativa,
confirmando una correlación alta entre las dos variables con un P = 0.00,
demostrando una correlación inversa de 0.776 que resultó ser significativa.
Asimismo, también se observó que existe una correlación entre las
dimensiones y el rendimiento ocupacional, siendo significativas a un nivel de p
< 0.00
Gender Justice In The Americas: A Transnational Dialogue On Sexuality, Violence, Reproduction, And Human Rights
Exploring Frontiers: The Application of Artificial Intelligence in Educational Assessment
Este artículo aborda la integración de la inteligencia artificial (IA) en la evaluación educativa, buscando mejorar la eficacia y objetividad de los métodos tradicionales. La creciente complejidad de los sistemas educativos ha generado la necesidad de herramientas más avanzadas para evaluar el rendimiento de los estudiantes. El estudio tiene como objetivo principal explorar el impacto de la IA en la evaluación educativa, identificando sus ventajas y desafíos. Se propone analizar cómo las tecnologías emergentes pueden adaptarse a la diversidad de estilos de aprendizaje y optimizar la retroalimentación. Se llevó a cabo una revisión de la literatura, seguida de un análisis de casos de implementación de IA en entornos educativos. Además, se realizaron entrevistas a educadores para obtener percepciones cualitativas. La IA demostró mejorar la precisión de la evaluación, personalizar la retroalimentación y proporcionar insights valiosos sobre los patrones de aprendizaje. Sin embargo, se destacaron preocupaciones éticas y desafíos técnicos que requieren atención. La integración de IA en la evaluación educativa es prometedora, pero se deben abordar cuestiones éticas y técnicas. La combinación de la experiencia humana con la capacidad analítica de la IA puede optimizar la evaluación y promover la equidad en la educación.This article delves into the integration of artificial intelligence (AI) in educational assessment, aiming to enhance the effectiveness and objectivity of traditional methods. The escalating complexity of educational systems has prompted the need for more advanced tools to evaluate student performance. The primary objective of the study is to explore the impact of AI on educational assessment, identifying its advantages and challenges. The analysis seeks to understand how emerging technologies can adapt to diverse learning styles and optimize feedback. A literature review was conducted, followed by a case analysis of AI implementation in educational settings. Additionally, interviews with educators were conducted to gather qualitative insights. AI demonstrated improvements in assessment accuracy, personalized feedback, and valuable insights into learning patterns. However, ethical concerns and technical challenges were highlighted, requiring attention. The integration of AI in educational assessment shows promise, but ethical and technical issues must be addressed. Combining human expertise with AI's analytical capability can optimize assessment and promote equity in education
Tos Ferina en una lactante no inmunizada: a propósito de un caso
ResumenIntroducciónLas afecciones respiratorias son un problema de salud común entre los lactantes.Reporte de casoUna lactante de 75 días de edad fue llevada a urgencias por disnea y tos paroxística espasmódica, emetizante y cianosante. No estaba inmunizada contra tos ferina y tuvo contacto con su gemela, que tenía una infección por probable Bordetella pertussis. El diagnóstico de egreso fue bronquiolitis. Días después, reingresó por disnea.DiscusiónEn los lactantes, la tos ferina, el síndrome coqueluchoide y la bronquiolitis tienen manifestaciones clínicas comunes. Este caso resalta la importancia de seguir las guías de práctica clínica y los procedimientos de diagnóstico de B. pertussis, así como el análisis epidemiológico de los casos probables, debido a que de ello depende el tratamiento etiológico y, por lo tanto, el pronóstico de los pacientes.AbstractIntroductionRespiratory tract infections are a common cause of infant morbidity, and even mortality.Case reportA two-month old female was taken to the Emergency Department after she suddenly developed dyspnoea and a paroxysmal, spasmodic, cyanosing cough. Her vaccination scheme was incomplete and she had contact with her twin sister, who had an infection probably caused by Bordetella pertussis. The discharge diagnosis was bronchiolitis. She was re-admitted to hospital a few days later with an exacerbation of her dyspnoea.DiscussionThis case highlights the importance of following the clinical practice guidelines and the standard procedures for the diagnosis of B. pertussis, while the epidemiological context of patients should always be considered. It is important to correctly identify the aetiological agent, as the specific treatment is based on the aetiology, and both of them determine the prognosis of the patients
Powered bone marrow biopsy procedures produce larger core specimens, with less pain, in less time than with standard manual devices
Bone marrow sampling remains essential in the evaluation of hematopoietic and many non-hematopoietic disorders. One common limitation to these procedures is the discomfort experienced by patients. To address whether a Powered biopsy system could reduce discomfort while providing equivalent or better results, we performed a randomized trial in adult volunteers. Twenty-six subjects underwent bilateral biopsies with each device. Core samples were obtained in 66.7% of Manual insertions; 100% of Powered insertions (P=0.002). Initial mean biopsy core lengths were 11.1±4.5 mm for the Manual device; 17.0±6.8 mm for the Powered device (P<0.005). Pathology assessment for the Manual device showed a mean length of 6.1±5.6 mm, width of 1.0±0.7 mm, and volume of 11.0±10.8 mm3. Powered device measurements were mean length of 15.3±6.1 mm, width of 2.0±0.3 mm, and volume of 49.1±21.5 mm3 (P<0.001). The mean time to core ejection was 86 seconds for Manual device; 47 seconds for the Powered device (P<0.001). The mean second look overall pain score was 33.3 for the Manual device; 20.9 for the Powered (P=0.039). We conclude that the Powered biopsy device produces superior sized specimens, with less overall pain, in less time
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