Mostrando ítems 81-100 de 1587

Mentoría entre pares: Un análisis desde la retroalimentación entre compañeros en el aprendizaje en línea

Avendaño Castro, William Rodrigo (Revista de Ciencias SocialesMaracaibo, Venezuela, 2023-12-07)

El objetivo de la investigación fue analizar las percepciones sobre la retroalimentación entre compañeros que se contextualizan y establecen en la mentoría entre pares en el aprendizaje en línea del contexto ...
Evaluación del control de Burkholderia glumae en arroz (Oryza sativa) FEDEARROZ 67, utilizando nanopartículas de plata (AgNPs) en condiciones de invernadero

Morales Becerra, Carlos Ernesto; Ortiz Rojas, Luz Yineth; Chaves-Bedoya, Giovanni (Revista Colombiana de Ciencias HorticolasTunja, Colombia, 2023-09-01)

El tizón bacteriano de la panícula, causado por Burkholderia glumae , representa una amenaza significativa para la producción mundial de arroz, poniendo en peligro la seguridad alimentaria futura. La gravedad de esta ...
Competencias TIC en profesores de comunicación en tiempos de COVID-19

QUINTERO LEÓN, MARGARITA; Ortiz Záccaro, Zulma Zoraida; Diaz Santana, Daivy; Espinel Rubio, Gladys Adriana; BOHORQUEZ-PEREIRA, GIOVANNI; Baltar Moreno, Adolfo (Magis, 2023-12-26)

Se exploran las percepciones de los estudiantes sobre las competencias digitales de sus docentes en cinco universidades de Colombia. La metodología aplicada es cuantitativa, con una encuesta aplicada a 606 estudiantes de ...
Thermohydraulic and Economic Evaluation of a New Design for Printed Circuit Heat Exchangers in Supercritical CO2 Brayton Cycle

Villada Castillo, Dora Clemencia; Valencia, Guillermo; Duarte Forero, Jorge (Energies, 2023-02-28)

The present study focused on the analysis of a new geometrical modification of the conventional zig-zag channel for Printed Circuit Heat Exchangers. The research was carried out using OpenFOAM and Salome software, which ...
Tribocorrosion-Resistant Surface for TiO2 as a Function of Load and Sliding Speed

Bautista-Ruiz, Jorge; Aperador Chaparro, William Arnulfo; Sanchez Molina, Jorge (Lubricants, 2023-02-21)

The applications projected in the coatings are in implants with the lower extremities since they require a great load capacity and are essential for walking. Therefore, the use of devices or implants is necessary for ...
Ética de los sentimientos, desarrollo de capacidades, memoria histórica y reconciliación: la fragilidad del personal de salud en el conflicto armado colombiano

Bautista Espinel, Gloria Omaira; Gonzalez Escobar, Dianne Sofia; Díaz Monsalve, Sonia; Bermúdez, Ana María (Revista de Bioetica y DerechoBarcelona, 2023-02-15)

analizar la forma en que los sentimientos y la recuperación de la memoria colectiva, posibilitan la disminución de la fragilidad social y política de los integrantes de la Misión Médica, haciendo factible ...
Innovative Technology Strategies for the Sustainable Development of Self-Produced Energy in the Colombian Industry

Orjuela Abril, Martha Sofia ; Torregroza Espinosa, Ana Carolina; Duarte Forero, Jorge (Sustainability (Switzerland), 2023-03-24)

This research studies the current state of the Colombian industrial sector, which is focused on self-generation processes. The study’s objective is to search for viable technological strategies that strengthen this ...
Bicarbonate-Hydrogen Peroxide System for Treating Dyeing Wastewater: Degradation of Organic Pollutants and Color Removal

Urbina-Suarez, Nestor Andres; Rivera Caicedo, Christian; González-Delgado, Angel Darío; Barajas Solano, andres F; Machuca-Martínez, Fiderman (Toxics, 2023-04-11)

: The textile industry is a global economic driving force; however, it is also one of the most polluting industries, with highly toxic effluents which are complex to treat due to the recalcitrant nature of some compounds ...
Effect of Temperature on the Tribological Properties of Hafnium Carbonitrides Coatings

Aperador Chaparro, William Arnulfo; Bautista-Ruiz, Jorge; Sanchez Molina, Jorge (Metals, 2023-04-21)

For industrial processes in which refractory metals are necessary, hafnium carbonitride exhibits excellent performance due to its high thermal conductivity and resistance to oxidation. In this study, hafnium carbonitride ...
Competencia cultural en estudiantes de enfermería de una Universidad Pública de Colombia

Sequeda Villarraga, Francy Lizeth; Ureña Parra, Maria Natalia; Velnadia Galvis, Martha Ligia; ZAMBRANO PLATA, GLORIA ESPERANZA (Revista CuidarteBucaramanga,Colombia, 2023-04-28)

La diversidad representa un desafío en la atención en salud, pues supone que los enfermeros sean culturalmente competentes, capaces de brindar cuidados que se adapten a las creencias, valores y prácticas de ...
Impact of Biomass Drying Process on the Extraction Efficiency of C-Phycoerythrin

Vergel Suarez, Ariadna Hazel; García-Martinez, Janet; López Barrera, German Luciano; Barajas Solano, andres F; ZUORRO, Antonio (BioTech, 2023-04-23)

Drying the biomass produced is one of the critical steps to avoid cell degradation; however, its high energy cost is a significant technological barrier to improving this type of bioprocess’s technical and economic ...
Redes sociodigitales y saberes colectivos de los venezolanos en Bogotá

Peña Garnica, Diego Fernando; Espinel Rubio, Gladys Adriana (Bitacora Urbano TerritorialBogotá,Colombia, 2023-08)

El objetivo del estudio es reconocer las dinámicas de redes y saberes colectivos dentro de la comunidad migrante venezolana en Bogotá (Colombia) durante la pandemia por COVID-19. Desde una perspectiva mixta exploratoria, ...
A Modified Radiopropagation Multipath Model for Constant Refractivity Gradient Profiles

Parada Rozo, Diego Andres; Rego, Cassio; Guevara-Ibarra, Dinael; Navarro, Andres; Ramos, Glaucio; Oliveira, Rodrigo (Journal of Microwaves, Optoelectronics and Electromagnetic Applications, 2023-06)

This paper presents a radiopropagation algorithm based on a Ray Tracing (RT) technique that combines a modified multipath model for constant refractivity gradient profiles and the Uniform Theory of Diffraction (UTD). A ...
HYPERBRANCHED ALKYD RESINS OBTAINED FROM A HYPERBRANCHED POLYESTER POLYOL OF THE FIFTH GENERATION AND TALL OIL FATTY ACID

Murillo Ruiz, Edwin Alberto; Raba Paez, Angela Mercedes (Rasayan Journal of Chemistry, 2023-09)

The first aim of this study was to synthesize hyperbranched alkyd resins from tall oil fatty acids and a hyperbranched polyester polyol via an esterification reaction. The second aim was to evaluate the effect of the fatty ...
In Vitro antifungal activity of ethanol extracts from Cnidoscolus urens L. in controlling Colletotrichum spp. in Lycopersicum esculentum: a sustainable agricultural perspective

Carrillo, Maria Fernanda; Mora Estupiñan, Daniela Alejandra; Ortiz, Luz; Chaves-Bedoya, Giovanni (Revista Colombiana de Ciencias Horticolas, 2023-05-01)

Anthracnose, caused by the pathogenic fungi Colletotrichum spp., poses a significant threat to table tomato (Lycopersicum esculentum) cultivation. This study delves into the potential of plant extracts from Cnidoscolus ...
Analysis of a three-dimensional numerical modeling approach for predicting scour processes in longitudinal walls of granular bedding rivers

calixto, nelson javier; CORTÉS ZAMBRANO, MELQUISEDEC; Galvis-Castaño, Alberto; Carrillo-Soto, Gustavo A (EUREKA: Physics and EngineeringEstonia, 2023-07-27)

In rivers, longitudinal walls are protective structures that are directly supported on the riverbank are frequently used as hydraulic prevent the current from eroding the bank and causing scouring. However, these structures ...
Using the Response Surface Methodology to Treat Tannery Wastewater with the Bicarbonate-Peroxide System

Urbina-Suarez, Nestor Andres; Salcedo Pabón, Cristian Jesús; López Barrera, German Luciano; García-Martinez, Janet; Barajas Solano, andres F; Machuca-Martínez, Fiderman (ChemEngineering, 2023-07-16)

A bicarbonate-peroxide (BAP) system was evaluated to improve the quality of industrial tannery wastewater using an I-optimal experimental design with four variables (temperature, initial pH, bicarbonate, and H2O2 concentration). ...
Geopolymers Based on a Mixture of Steel Slag and Fly Ash, Activated with Rice Husks and Reinforced with Guadua angustifolia Fibers

Aperador Chaparro, William Arnulfo; Bautista-Ruiz, Jorge; Sanchez Molina, Jorge (Sustainability (Switzerland), 2023-08-15)

At present, the conservation of the environment represents an objective that everyone wants to achieve. The construction industry has influenced the advancement of alternative materials that comply with sustainable ...
Leachate Treatment via TiO2/UV Heterogeneous Photocatalysis: A Multiple Polynomial Regression Model

Becerra Moreno, Dorance; Machuca-Martínez, Fiderman; Maturana Cordoba, Aymer Yeferson; Villamizar, Salvador; SOTO VERJEL, JOSEPH WBEIMAR; Soto Vergel, Angelo Joseph (Ingeniería e InvestigaciónBogotá,Colombia, 2023-12-13)

Advanced oxidation processes such as TiO2/UV heterogeneous photocatalysis are suitable treatment methods for wastewater with high pollutant loads such as landfill leachates. Optimizing the variables that ...
Leasing como herramienta de financiamiento para las MIPYME del sector del calzado del municipio de Cúcuta

rueda vera, gerson; CASADIEGO DUQUE, YAIR ROLANDO; Avendaño Castro, William Rodrigo (Revista Venezolana de GerenciaMaracaibo,Venezuela, 2023-08-05)

El objetivo fue determinar si hay o no diferencias entre el conocimiento sobre el leasing en relación con la aceptación del leasing y los beneficios del arrendamiento financiero como herramienta de financiación por parte ...

Envíos recientes

Mentoría entre pares: Un análisis desde la retroalimentación entre compañeros en el aprendizaje en línea
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Avendaño Castro, William Rodrigo | 2023-12-07

El objetivo de la investigación fue analizar las percepciones sobre la retroalimentación entre compañeros que se contextualizan y establecen en la mentoría entre pares en el aprendizaje en línea del contexto universitario por parte de los actores educativo (estudiantes y profesores) de contabilidad I, Facultad de Ciencias Empresariales de la Universidad Francisco de Paula Santander-Colombia. La investigación, se realizó bajo un enfoque mixto, de tipo descriptiva. La muestra estuvo compuesta por 70 estudiantes, y 6 informantes clave. Los instrumentos utilizados fueron la encuesta, observación y entrevista semiestructurada. El estudio mostró que un grupo importante mayor al 50% percibe de manera positiva la mentoría y retroalimentación entre pares en línea, apreciando la clase aplicada en línea por el compañero-mentor. A su vez, el estudio develó que la observación de asistencia mutua entre pares impulsa el aprendizaje autoactivo, como vehículo de capacitación continua que se adapta y vincula a la cultura de aprendizaje en línea. Se concluye que, en la mentoría entre pares, la retroalimentación en el aprendizaje en línea se asocia con la cooperación y colaboración, compañerismo e interacción, donde el diálogo es una conversación, un flujo de conciencia, donde las personas se encuentran como iguales y en una relación respetuosa

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Evaluación del control de Burkholderia glumae en arroz (Oryza sativa) FEDEARROZ 67, utilizando nanopartículas de plata (AgNPs) en condiciones de invernadero
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Morales Becerra, Carlos Ernesto | 2023-09-01

El tizón bacteriano de la panícula, causado por Burkholderia glumae , representa una amenaza significativa para la producción mundial de arroz, poniendo en peligro la seguridad alimentaria futura. La gravedad de esta enfermedad transmitida por las semillas se ha visto amplificada por las condiciones ambientales cambiantes, pero siguen siendo difíciles de alcanzar estrategias de control eficaces y variedades de arroz totalmente resistentes. Esta investigación se realizó con la variedad de arroz FEDEARROZ 67 proveniente de Agua Clara, municipio de Cúcuta, y las pruebas se realizaron en condiciones controladas de invernadero en la Universidad Francisco de Paula Santander. Nuestro objetivo fue evaluar el potencial de las nanopartículas de plata (AgNP) sintetizadas electroquímicamente para controlar B. glumae . Se empleó un diseño completamente al azar con cinco tratamientos: preventivo, curativo, control positivo, control negativo y control absoluto. Las variables analizadas incluyeron el número de hojas cloróticas, altura y peso de la planta. Los análisis estadísticos abarcaron análisis de varianza y pruebas de comparación de medias de Tukey utilizando XLSTATS versión 2018. Nuestros hallazgos revelaron que el tratamiento preventivo con AgNP en una concentración de 5 ppm exhibió efectos fitoprotectores significativos contra B. glumae . Las plantas bajo este tratamiento mostraron menos síntomas cloróticos y mayores alturas y pesos en comparación con los controles. Estos hallazgos subrayan el potencial de la nanotecnología como herramienta innovadora para combatir enfermedades bacterianas en cultivos esenciales como el arroz, contribuyendo así a un futuro sostenible para la agricultura mundial.

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Competencias TIC en profesores de comunicación en tiempos de COVID-19
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QUINTERO LEÓN, MARGARITA | 2023-12-26

Se exploran las percepciones de los estudiantes sobre las competencias digitales de sus docentes en cinco universidades de Colombia. La metodología aplicada es cuantitativa, con una encuesta aplicada a 606 estudiantes de comunicación social, quienes evaluaron las competencias (comunicativa, TIC y pedagógica) de los profesores de acuerdo con lo establecido por el Ministerio de Educación Nacional, desde tres niveles de dominio: explorador, integrador e innovador. Los docentes fueron valorados positivamente, siendo la competencia comunicativa la que obtuvo mayor registro (91,30 %). Se propone transitar, del aprendizaje de la tecnología, al aprendizaje con la tecnología.

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Thermohydraulic and Economic Evaluation of a New Design for Printed Circuit Heat Exchangers in Supercritical CO2 Brayton Cycle
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Villada Castillo, Dora Clemencia | 2023-02-28

The present study focused on the analysis of a new geometrical modification of the conventional zig-zag channel for Printed Circuit Heat Exchangers. The research was carried out using OpenFOAM and Salome software, which were used for the CFD analysis and the construction of the computational domain. For the development of the study, three types of channel geometries were defined: a modified zig-zag channel, a conventional zig-zag channel, and a straight channel. The results show that the modified zig-zag channel achieves better thermal hydraulic performance compared to that of the conventional zig-zag channel, evidenced by a 7.6% increase in the thermal performance factor. The modified zig-zag channel proposed in the research caused a 1.5% reduction of the power consumption of supercritical Brayton cycle compressors. Additionally, the modified zig-zag channel achieves a maximum efficiency of 49.1%, which is 1.5% higher compared to that of the conventional zig-zag channel. The above results caused a 20.9% reduction of the operating costs of the supercritical Brayton cycle. This leads to a 5.9% decrease in the cost associated with using the PCHE compared to that of the conventional zig-zag channel. In general, the new geometric characteristics proposed for the conventional zig-zag channel minimize the high loss of the hydraulic performance without significantly compromising its heat transfer capacity. The geometric analysis of the proposed new zig-zag channel geometry was limited to evaluating the influence of the bend angle of 20–30◦ . Therefore, a more detailed geometric optimization process involving other geometric parameters of the channel is still needed. Future research will be focused on addressing this approach

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Tribocorrosion-Resistant Surface for TiO2 as a Function of Load and Sliding Speed
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Bautista-Ruiz, Jorge | 2023-02-21

The applications projected in the coatings are in implants with the lower extremities since they require a great load capacity and are essential for walking. Therefore, the use of devices or implants is necessary for recovery, osteosynthesis, and fixation. The tribocorrosive behavior of nanostructured compounds based on titanium oxide with an intermediate layer of gold deposited on titanium substrates was determined. These coatings were obtained using the reactive magnetron sputtering technique. Tribocorrosive properties were evaluated at sliding speeds of 3500 mm/min, 4500 mm/min, 6000 mm/min, 7500 mm/min, and 9000 mm/min with loads of 1 N, 2 N, 3 N, 4 N, and 5 N. The coatings were characterized by X-ray photoemission spectroscopy and X-ray diffraction, and the surface roughness was analyzed by atomic force microscopy. The dual mechanical and electrochemical wear tests were carried out with a potentiostat coupled to a pin on the disk system. The system was in contact with a hanks solution (37 ◦C), which acted as a lubricant. Structural characterization made it possible to identify the TiO2 compound. In the morphological characterization, it was found that the substrate influenced the surface properties of the coatings. The tribological behavior estimated by the wear rates showed less wear at higher load and sliding speeds. It was shown that it is possible to obtain coatings with better electrochemical and tribological performance by controlling the applied load and slip speed variables. In this study, a significant decrease corresponding to 64% was obtained, specifically in the speed of deterioration, and especially for a load of 5 N, depending on the sliding speed that went from 0.2831 mpy (Mils penetration per year) to 3500 mm/min compared to 0.1045 mpy at 9000 mm/min, which is explained by the mechanical blockage induced by the coating.

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Ética de los sentimientos, desarrollo de capacidades, memoria histórica y reconciliación: la fragilidad del personal de salud en el conflicto armado colombiano
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Bautista Espinel, Gloria Omaira | 2023-02-15

analizar la forma en que los sentimientos y la recuperación de la memoria colectiva, posibilitan la disminución de la fragilidad social y política de los integrantes de la Misión Médica, haciendo factible nuevas maneras de participación, mediante el desarrollo de capacidades deliberativas desde la perspectiva bioética. Metodología: estudio exploratorio con enfoque cualitativo, que toma en cuenta la subjetividad e intersubjetividad de los participantes. Con fuentes de información heterogénea: grupos focales, entrevistas semiestructuradas y cartillas de campo, se constituyó un marco de factores relevantes, que permitieron procesar la información, mediante relaciones y categorizaciones conceptuales,para su posterior triangulación. Resultados: los sentimientos con mayor impacto ético en Misión Médica: incertidumbre, inseguridad ante el trabajo, ansiedad por los hechos de violencia, tristeza, temor, miedo e impotencia; producen efectos emocionales relacionados con el principio de maleficencia. La resiliencia, ha impedido realizar ejercicios de memoria colectiva, a causa del negacionismo y temor a recordar los hechos más significativos, esto les ha impedido el acceso a los mecanismos de Justicia Restaurativa. La ausencia de capacidades para afrontar la situación compromete la autonomía individual, la salud laboral y genera carencias legales no resueltas. Conclusiones: los sentimientos colectivos en el ámbito público del personal sanitario prevalecen sobre los sentimientos individuales basados en vivencias, que afectan la capacidad de deliberación, esto implica promover ejercicios de memoria colectiva, sobre los hechos del conflicto, mediante el desarrollo de capacidades que fortalezcan la legitima defensade su autonomía y el desarrollo de un ejercicio profesional beneficiente, ante situaciones limítrofes de confrontación.

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Innovative Technology Strategies for the Sustainable Development of Self-Produced Energy in the Colombian Industry
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Orjuela Abril, Martha Sofia | 2023-03-24

This research studies the current state of the Colombian industrial sector, which is focused on self-generation processes. The study’s objective is to search for viable technological strategies that strengthen this particular sector’s competitiveness and sustainable development. The analysis shows that internal combustion engines represent 49% of the technologies used for self-generation. The main fuel used in the sector is natural gas, with a percentage of 56%. The lack of strategies for the use of residual heat and technological inefficiencies caused a loss of 36% in the energy used in the Colombian industrial sector. Thermoelectric generators are a feasible way to recover energy from exhaust gases in engines used for self-generation. Additionally, they allow a 4% reduction in fuel consumption and an improvement in the engine’s energy efficiency. The use of hydrogen as fuel allows a 30% reduction in polluting emissions, such as CO2 , CO, HC, and particulate matter. Hydrogen production processes, such as water electrolysis, allow the participation of Colombia’s solar energy potential, leading to sustainable hydrogen production, efficiency (60–80%), and a lower economic cost. In general, the application of thermoelectric generators and the use of hydrogen gas allow the improvement of the Colombian industrial sector’s environmental, social, and economic aspects due to greater competitiveness and the reduction in emissions and operating costs.

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Bicarbonate-Hydrogen Peroxide System for Treating Dyeing Wastewater: Degradation of Organic Pollutants and Color Removal
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Urbina-Suarez, Nestor Andres | 2023-04-11

: The textile industry is a global economic driving force; however, it is also one of the most polluting industries, with highly toxic effluents which are complex to treat due to the recalcitrant nature of some compounds present in these effluents. This research focuses on the removal of Chemical Oxygen Demand (COD), color, Total Organic Carbon (TOC), and Ammoniacal Nitrogen (N-NH3 ) on tannery wastewater treatment through an advanced oxidation process (AOPs) using sodium bicarbonate (NaHCO3 ), hydrogen peroxide (H2O2 ) and temperature using a central composite non-factorial design with a surface response using Statistica 7.0 software. All experiments used a 500 mL reactor with 300 mL of tannery wastewater from a company in Cúcuta, Colombia. The physicochemical characterization was done to determine the significant absorbance peaks about the color in the wavelengths between 297 and 669 nm. Statistical analysis found that the concentration of NaHCO3 affects the removal of color and N-NH3 ; however, it did not affect COD and TOC. The optimal process conditions for removing the different compounds under study were: NaHCO3 1 M, H2O2 2 M, and 60 ◦C, with efficiencies of 92.35%, 31.93%, 68.85%, and 35.5% N-NH3 , COD, color, and TOC respectively. It can be concluded that AOPs using H2O2 and NaHCO3 are recommended to remove color and N-NH3.

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Effect of Temperature on the Tribological Properties of Hafnium Carbonitrides Coatings
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Aperador Chaparro, William Arnulfo | 2023-04-21

For industrial processes in which refractory metals are necessary, hafnium carbonitride exhibits excellent performance due to its high thermal conductivity and resistance to oxidation. In this study, hafnium carbonitride was deposited on Inconel 718 steel and silicon (100) substrates. The objective was to characterize the wear properties as a function of temperature. The layers were deposited by physical vapor deposition (PVD) in an R.F. sputtering magnetron system from carbon targets and high-purity hafnium (99.99%). The wear tests were carried out at temperatures of 100 ◦C, 200 ◦C, 400 ◦C, and 800 ◦C in non-lubricated conditions. The coefficient of friction (COF) was recorded in situ. The heat treatment temperature on coatings is essential in determining anti-wear efficiency. It was determined that high temperatures (800 ◦C) improve resistance to wear. High-resolution XPS spectra were used to detect the chemical states of Hf 4f5/2 and Hf 4f7/2. The 4f5/2 and 4f7/2 binding energy indicates the presence of HfN and HfC. Using the TEM technique in bright field mode allowed us to know the orientation, crystallographic structure and interplanar distances of the HfCN. The topography of the coatings, by AFM, shows uniform grains and very small characteristics that determine the low surface roughness value. The SEM image of the cross-section of the HfCN coating shows homogeneity of the layer; no cracks or deformations are observed.

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Competencia cultural en estudiantes de enfermería de una Universidad Pública de Colombia
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Sequeda Villarraga, Francy Lizeth | 2023-04-28

La diversidad representa un desafío en la atención en salud, pues supone que los enfermeros sean culturalmente competentes, capaces de brindar cuidados que se adapten a las creencias, valores y prácticas de los pacientes provenientes de diversas culturas. Objetivo: Determinar el nivel de competencia cultural en los estudiantes de enfermería de una Universidad Pública de Colombia. Materiales y métodos: Estudio cuantitativo descriptivo de corte transversal. Para la recolección de datos se utilizó la Escala de Competencia Cultural versión en español chilena, previamente validada en el contexto colombiano. La muestra estuvo conformada por 148 estudiantes de enfermería matriculados de tercer a octavo semestre, en el periodo de agosto a diciembre del 2021. Se realizó análisis univariado y bivariado mediante la prueba U de Mann Whitney y H de Kruskal Wallis. Resultados: El puntaje promedio (72.3), obtenido por los estudiantes de enfermería indica niveles moderados de competencia cultural. Se halló diferencias significativas del nivel de competencia respecto a la formación previa (p < 0.05) y a la experiencia en cuidado de pacientes con diversas culturas (p< 0.05). Discusión: Los participantes en este estudio mostraron niveles de competencia cultural similares a los encontrados en investigaciones realizadas con estudiantes de enfermería en otros países, como Corea del Sur, India, Sudáfrica, Irak, y Chile, entre otros. Conclusiones:El nivel de competencia cultural de los estudiantes de enfermería, les permite brindar acciones seguras humanas empáticas, efectivas y coherentes con la cultura de los pacientes. Palabras Clave: Competencia cultural; Formación profesional; Diversidad cultural; Estudiantes de enfermería.Open access E-ISSN: 2346-3414

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Impact of Biomass Drying Process on the Extraction Efficiency of C-Phycoerythrin
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Vergel Suarez, Ariadna Hazel | 2023-04-23

Drying the biomass produced is one of the critical steps to avoid cell degradation; however, its high energy cost is a significant technological barrier to improving this type of bioprocess’s technical and economic feasibility. This work explores the impact of the biomass drying method of a strain of Potamosiphon sp. on the extraction efficiency of a phycoerythrin-rich protein extract. To achieve the above, the effect of time (12–24 h), temperature (40–70 ◦C), and drying method (convection oven and dehydrator) were determined using an I-best design with a response surface. According to the statistical results, the factors that most influence the extraction and purity of phycoerythrin are temperature and moisture removal by dehydration. The latter demonstrates that gentle drying of the biomass allows removing the most significant amount of moisture from the biomass without affecting the concentration or quality of temperature-sensitive proteins.

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Redes sociodigitales y saberes colectivos de los venezolanos en Bogotá
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Peña Garnica, Diego Fernando | 2023-08

El objetivo del estudio es reconocer las dinámicas de redes y saberes colectivos dentro de la comunidad migrante venezolana en Bogotá (Colombia) durante la pandemia por COVID-19. Desde una perspectiva mixta exploratoria, en la que convergen la observación focalizada, la encuesta y la entrevista, fue posible analizar el flujo de contenidos en las redes sociodigitales, las visiones de expertos en atención a población migrante y las realidades de esta comunidad. Se comprobó que las redes administradas por ellos se configuran en una infraestructura comunicativa bidireccional y permanente que les permite intercambiar conocimientos prácticos a través de la inteligencia colectiva, logrando su supervivencia, no solo frente a la pandemia, sino en relación con su salud mental y sus medios de vida durante el confinamiento físico obligatorio.

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$Portada A Modified Radiopropagation Multipath Model for Constant Refractivity Gradient Profiles$

A Modified Radiopropagation Multipath Model for Constant Refractivity Gradient Profiles
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Parada Rozo, Diego Andres | 2023-06

This paper presents a radiopropagation algorithm based on a Ray Tracing (RT) technique that combines a modified multipath model for constant refractivity gradient profiles and the Uniform Theory of Diffraction (UTD). A novel formulation is proposed by the authors for calculation and ground-reflection analysis of ray paths depending on atmospheric refractivity. The algorithm introduced herein was evaluated in a mixed scenario and in two more realistic case studies, under conditions of constant refractivity gradient and lossy terrain profiles. Pathloss results are obtained and compared with Parabolic Equation (PE) numerical solution results at 2.0 GHz, 3.5 GHz and 5.4 GHz. In such conditions, the modified radiopropagation multipath algorithm with atmospheric refractivity introduced herein showed satisfactory results.

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HYPERBRANCHED ALKYD RESINS OBTAINED FROM A HYPERBRANCHED POLYESTER POLYOL OF THE FIFTH GENERATION AND TALL OIL FATTY ACID
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Murillo Ruiz, Edwin Alberto | 2023-09

The first aim of this study was to synthesize hyperbranched alkyd resins from tall oil fatty acids and a hyperbranched polyester polyol via an esterification reaction. The second aim was to evaluate the effect of the fatty acid proportion on the properties of the resins. The modification percentage of the hyperbranched polyester polyol was between 47.68 and 66.02%. Infrared analysis shows that the alkyd resins decreased the intensity of the OH group's vibration. This decrease depends on the amount of TOFA used. Thermogravimetric and differential scanning calorimetry analyses showed that the modification of the hyperbranched polyester improved the thermal stability and the mobility of the macromolecules of the alkyd resins respectively. The viscosity of the alkyd resins was less than 10 Pa.s. They exhibited Newtonian behavior and had the highest gloss values at 60° (between 90.1 and 91.6).

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In Vitro antifungal activity of ethanol extracts from Cnidoscolus urens L. in controlling Colletotrichum spp. in Lycopersicum esculentum: a sustainable agricultural perspective
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Carrillo, Maria Fernanda | 2023-05-01

Anthracnose, caused by the pathogenic fungi Colletotrichum spp., poses a significant threat to table tomato (Lycopersicum esculentum) cultivation. This study delves into the potential of plant extracts from Cnidoscolus urens L. as an alternative biocontrol strategy to combat this disease. Rich in secondary metabolites like terpenes, which are instrumental in plant defense, these extracts also comprise esters and fatty acids. Although the latter are not classified as secondary metabolites, they contribute significantly to the plant's biochemical makeup. Our objective was to gauge the in vitro inhibitory efficacy of ethanolic extracts derived from the leaves and stems of Cnidoscolus urens L. against Colletotrichum spp. To achieve this, an agar dilution method with varying extract concentrations was employed. The results showed that concentrations ranging from treatment 3 to treatment 8 effectively inhibited fungal mycelial growth. Interestingly, the extracts' origin, whether from leaves or stems, did not show any significant differential impact on their inhibitory activity. These insights emphasize the consistent effect of Cnidoscolus urens L. extracts in stalling Colletotrichum spp. growth, underscoring their potential as biological antifungal agents in agriculture. Given the pronounced in vitro effectiveness of both leaf and stem extracts, they beckon further exploration as part of sustainable agricultural strategies to combat prominent diseases like anthracnose.

LEER
Analysis of a three-dimensional numerical modeling approach for predicting scour processes in longitudinal walls of granular bedding rivers
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calixto, nelson javier | 2023-07-27

In rivers, longitudinal walls are protective structures that are directly supported on the riverbank are frequently used as hydraulic prevent the current from eroding the bank and causing scouring. However, these structures have the potential to block flow and produce erosive processes that progressively worsen scour in their area, leading to faulting and other problems. The current study used Flow-3D software to understand the scour process at the base of longitudinal walls in rivers with a well-graded granular bed. Experimental data from a physical model replicating a river with a longitudinal wall and a well-graded granular bed were used to validate the model. The investigation examined the average flow velocity and its effects on scour behavior along the longitudinal wall using the Flow-3D program. The findings showed that the Flow-3D model could improve the evaluation of debugging processes, because it provided a useful answer that closely matched the experimental data derived from the physical model. Validation with a 0.07 m mesh demonstrated that the Flow-3D model could faithfully simulate the scour process along the longitudinal wall. Overall, the findings of this study suggest that the Flow-3D software can be a useful tool for predicting the scouring process in rivers with well-graded granular beds and longitudinal walls. This is particularly important for engineers and researchers who are interested in designing and optimizing hydraulic structures to mitigate the effects of scouring, because it provided a useful answer that closely matched the experimental data derived from the physical model

LEER
Using the Response Surface Methodology to Treat Tannery Wastewater with the Bicarbonate-Peroxide System
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Urbina-Suarez, Nestor Andres | 2023-07-16

A bicarbonate-peroxide (BAP) system was evaluated to improve the quality of industrial tannery wastewater using an I-optimal experimental design with four variables (temperature, initial pH, bicarbonate, and H2O2 concentration). The response variables were COD removal, ammonia nitrogen removal, and nitrate concentration. The most critical variables were optimized using a The process was carried out in 500 mL reactors, the operational volume of 250 mL, and the agitation was at 550 rpm. A new I-optimal reaction surface design at two levels (bicarbonate concentration 0.01–0.3 mol/L and H2O2 0.05–0.35 mol/L) was used to obtain the optimal data of the experimental design. Optimal conditions were validated by one-way ANOVA statistical analysis using Prism software. Temperatures above 50 °C promote the efficiency of the BAP system, and slightly acidic initial pHs allow stabilization of the system upon inclusion of bicarbonate and peroxide in the concentration of bicarbonate, which is critical for the reaction with peroxide and formation of reactive oxygen species. With the validated optimal data, removal percentages above 78% were achieved for nitrites, ammonia nitrogen, chromium, TSS, BOD, conductivity, chromium, and chlorides; for COD and TOC, removal percentages were above 45%, these results being equal and even higher than other AOPs implemented for this type of water.

LEER
Geopolymers Based on a Mixture of Steel Slag and Fly Ash, Activated with Rice Husks and Reinforced with Guadua angustifolia Fibers
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Aperador Chaparro, William Arnulfo | 2023-08-15

At present, the conservation of the environment represents an objective that everyone wants to achieve. The construction industry has influenced the advancement of alternative materials that comply with sustainable development. In this article, reinforced concrete was obtained by mixing 80% blast furnace slag and 20% fly ash. These concentrations were chosen because they provide the lowest porosity in the cementitious matrix. Rice husk ash was used as an activator. Guadua angustifolia fibers were used to evaluate the mechanical performance of the concrete. The composition of the raw material was determined by X-ray fluorescence, the microstructure of the fibers by AFM, and the SEM technique was used to determine the surface characteristics of guadua fibers and concrete mixes. The structural characterization using XRD, the structure of the molecules of the guadua fiber, and the composition of the mixture’s molecular mixtures were determined by FTIR spectroscopy. Its properties, such as tensile strength and flexural strength, were analyzed. The results indicated that the concrete with the addition of Guadua angustifolia fibers. The results indicated that the concrete with the addition of guadua angustifolia fibers showed the best mechanical behavior. Tensile strength was optimized, establishing values of 2.68 MPa for unreinforced concrete and up to 3.12 MPa for fiber-reinforced concrete. The flexural strength values increase at ages after 28 days due to the pozzolanic reaction generated. Values of 2.8 MPa were obtained for concrete without fiber and 3.5 MPa for concrete reinforced with guadua angustifolia fiber.

LEER
Leachate Treatment via TiO2/UV Heterogeneous Photocatalysis: A Multiple Polynomial Regression Model
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Becerra Moreno, Dorance | 2023-12-13

Advanced oxidation processes such as TiO2/UV heterogeneous photocatalysis are suitable treatment methods for wastewater with high pollutant loads such as landfill leachates. Optimizing the variables that influence the process is a fundamental aspect. However, in this regard, experimental conditions are limited in terms of resources and time, which is why modeling allows obtaining a general understanding of the phenomenon from a set of experimental data. This work sought to model the photocatalytic process via multivariate polynomial regression, considering variables such as the catalyst concentration, the pH level, and the accumulated energy concerning the percentage of degradation in terms of dissolved organic carbon (DOC). The implemented fitting method resulted in a third-degree polynomial with an R2 of 0,8652, concluding that the model and its conclusions are valid. Moreover, with greater degrees, the model curve overfitted, even with better R2. DOC abatement showed a negative correlation with pH and the catalyst dose, while an opposite trend was observed for the accumulated energy. The model predictions allow inferring that, at low catalyst doses and medium and high pH levels, it is possible to find maximum degradations at low cumulative energies

LEER
Leasing como herramienta de financiamiento para las MIPYME del sector del calzado del municipio de Cúcuta
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rueda vera, gerson | 2023-08-05

El objetivo fue determinar si hay o no diferencias entre el conocimiento sobre el leasing en relación con la aceptación del leasing y los beneficios del arrendamiento financiero como herramienta de financiación por parte de las MIPYME en la industria del calzado del municipio San José de Cúcuta (Norte Santander-Colombia. Metodológicamente la investigación tuvo un enfoque cuantitativo, de tipo descriptivo y correlacional. La muestra estuvo compuesta por 50 empresas del sector calzado en el municipio de San José de Cúcuta. El instrumento manipulado fue un cuestionario tipo likert de 5 alternativas. Los resultados evidencian que las empresas que tienen conocimiento de los tipos de contrato que le permite comprar un activo correlacionan positivamente con solicitar el financiamiento del bien, si permite una oportunidad de crecimiento para la empresa. Se concluyó, que la aceptación del leasing como herramienta de financiamiento para las MIPYME del sector del calzado del municipio de Cúcuta viene dada en primer lugar por el conocimiento que tenga la empresa sobre el leasing, seguido de la optimización de la gestión financiera y fiscal del bien o activo, con lo cual, la empresa preserva su efectivo para las necesidades del negocio evitando un shock en el flujo de caja.

LEER

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B. Investigación: Envíos recientes

Mentoría entre pares: Un análisis desde la retroalimentación entre compañeros en el aprendizaje en línea ﻿

Evaluación del control de Burkholderia glumae en arroz (Oryza sativa) FEDEARROZ 67, utilizando nanopartículas de plata (AgNPs) en condiciones de invernadero ﻿

Competencias TIC en profesores de comunicación en tiempos de COVID-19 ﻿

Thermohydraulic and Economic Evaluation of a New Design for Printed Circuit Heat Exchangers in Supercritical CO2 Brayton Cycle ﻿

Tribocorrosion-Resistant Surface for TiO2 as a Function of Load and Sliding Speed ﻿

Ética de los sentimientos, desarrollo de capacidades, memoria histórica y reconciliación: la fragilidad del personal de salud en el conflicto armado colombiano ﻿

Innovative Technology Strategies for the Sustainable Development of Self-Produced Energy in the Colombian Industry ﻿

Bicarbonate-Hydrogen Peroxide System for Treating Dyeing Wastewater: Degradation of Organic Pollutants and Color Removal ﻿

Effect of Temperature on the Tribological Properties of Hafnium Carbonitrides Coatings ﻿

Competencia cultural en estudiantes de enfermería de una Universidad Pública de Colombia ﻿

Impact of Biomass Drying Process on the Extraction Efficiency of C-Phycoerythrin ﻿

Redes sociodigitales y saberes colectivos de los venezolanos en Bogotá ﻿

A Modified Radiopropagation Multipath Model for Constant Refractivity Gradient Profiles ﻿

HYPERBRANCHED ALKYD RESINS OBTAINED FROM A HYPERBRANCHED POLYESTER POLYOL OF THE FIFTH GENERATION AND TALL OIL FATTY ACID ﻿

In Vitro antifungal activity of ethanol extracts from Cnidoscolus urens L. in controlling Colletotrichum spp. in Lycopersicum esculentum: a sustainable agricultural perspective ﻿

Analysis of a three-dimensional numerical modeling approach for predicting scour processes in longitudinal walls of granular bedding rivers ﻿

Using the Response Surface Methodology to Treat Tannery Wastewater with the Bicarbonate-Peroxide System ﻿

Geopolymers Based on a Mixture of Steel Slag and Fly Ash, Activated with Rice Husks and Reinforced with Guadua angustifolia Fibers ﻿

Leachate Treatment via TiO2/UV Heterogeneous Photocatalysis: A Multiple Polynomial Regression Model ﻿

Leasing como herramienta de financiamiento para las MIPYME del sector del calzado del municipio de Cúcuta ﻿

Envíos recientes

Mentoría entre pares: Un análisis desde la retroalimentación entre compañeros en el aprendizaje en línea

Evaluación del control de Burkholderia glumae en arroz (Oryza sativa) FEDEARROZ 67, utilizando nanopartículas de plata (AgNPs) en condiciones de invernadero

Competencias TIC en profesores de comunicación en tiempos de COVID-19

Thermohydraulic and Economic Evaluation of a New Design for Printed Circuit Heat Exchangers in Supercritical CO2 Brayton Cycle

Tribocorrosion-Resistant Surface for TiO2 as a Function of Load and Sliding Speed

Ética de los sentimientos, desarrollo de capacidades, memoria histórica y reconciliación: la fragilidad del personal de salud en el conflicto armado colombiano

Innovative Technology Strategies for the Sustainable Development of Self-Produced Energy in the Colombian Industry

Bicarbonate-Hydrogen Peroxide System for Treating Dyeing Wastewater: Degradation of Organic Pollutants and Color Removal

Effect of Temperature on the Tribological Properties of Hafnium Carbonitrides Coatings

Competencia cultural en estudiantes de enfermería de una Universidad Pública de Colombia

Impact of Biomass Drying Process on the Extraction Efficiency of C-Phycoerythrin

Redes sociodigitales y saberes colectivos de los venezolanos en Bogotá

A Modified Radiopropagation Multipath Model for Constant Refractivity Gradient Profiles

HYPERBRANCHED ALKYD RESINS OBTAINED FROM A HYPERBRANCHED POLYESTER POLYOL OF THE FIFTH GENERATION AND TALL OIL FATTY ACID

In Vitro antifungal activity of ethanol extracts from Cnidoscolus urens L. in controlling Colletotrichum spp. in Lycopersicum esculentum: a sustainable agricultural perspective

Analysis of a three-dimensional numerical modeling approach for predicting scour processes in longitudinal walls of granular bedding rivers

Using the Response Surface Methodology to Treat Tannery Wastewater with the Bicarbonate-Peroxide System

Geopolymers Based on a Mixture of Steel Slag and Fly Ash, Activated with Rice Husks and Reinforced with Guadua angustifolia Fibers

Leachate Treatment via TiO2/UV Heterogeneous Photocatalysis: A Multiple Polynomial Regression Model

Leasing como herramienta de financiamiento para las MIPYME del sector del calzado del municipio de Cúcuta

Portales Institucionales

Mentoría entre pares: Un análisis desde la retroalimentación entre compañeros en el aprendizaje en línea

Evaluación del control de Burkholderia glumae en arroz (Oryza sativa) FEDEARROZ 67, utilizando nanopartículas de plata (AgNPs) en condiciones de invernadero

Competencias TIC en profesores de comunicación en tiempos de COVID-19

Thermohydraulic and Economic Evaluation of a New Design for Printed Circuit Heat Exchangers in Supercritical CO2 Brayton Cycle

Tribocorrosion-Resistant Surface for TiO2 as a Function of Load and Sliding Speed

Ética de los sentimientos, desarrollo de capacidades, memoria histórica y reconciliación: la fragilidad del personal de salud en el conflicto armado colombiano

Innovative Technology Strategies for the Sustainable Development of Self-Produced Energy in the Colombian Industry

Bicarbonate-Hydrogen Peroxide System for Treating Dyeing Wastewater: Degradation of Organic Pollutants and Color Removal

Effect of Temperature on the Tribological Properties of Hafnium Carbonitrides Coatings

Competencia cultural en estudiantes de enfermería de una Universidad Pública de Colombia

Impact of Biomass Drying Process on the Extraction Efficiency of C-Phycoerythrin

Redes sociodigitales y saberes colectivos de los venezolanos en Bogotá

A Modified Radiopropagation Multipath Model for Constant Refractivity Gradient Profiles

HYPERBRANCHED ALKYD RESINS OBTAINED FROM A HYPERBRANCHED POLYESTER POLYOL OF THE FIFTH GENERATION AND TALL OIL FATTY ACID

In Vitro antifungal activity of ethanol extracts from Cnidoscolus urens L. in controlling Colletotrichum spp. in Lycopersicum esculentum: a sustainable agricultural perspective

Analysis of a three-dimensional numerical modeling approach for predicting scour processes in longitudinal walls of granular bedding rivers

Using the Response Surface Methodology to Treat Tannery Wastewater with the Bicarbonate-Peroxide System

Geopolymers Based on a Mixture of Steel Slag and Fly Ash, Activated with Rice Husks and Reinforced with Guadua angustifolia Fibers

Leachate Treatment via TiO2/UV Heterogeneous Photocatalysis: A Multiple Polynomial Regression Model

Leasing como herramienta de financiamiento para las MIPYME del sector del calzado del municipio de Cúcuta