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Characterization of the morphological and chemical profile of different families of microplastics in samples of breathable air
No full textMicroplastic (MP) contamination has become a problem of great interest to the community at large. The detection of these particles in different ecosystems and foods has been the subject of study. However, the focus of these investigations has been on the identification and quantification of PM by DSC and Pyr-GC/MS and not on how they are transported to reach the air we breathe. In this study, the values of morphological parameters for plastic particles in a range between 1 and 2000 µm, present in the breathable air of 20 neighborhoods in the city of Cartagena, Colombia, were obtained to determine the characteristics that make these particles airborne. The values of parameters were obtained, such as roundness, sphericity, curvature, and the convexity of the particle, as well as its compactness and size, which influence its transport through the air and its ability to be ingested and inhaled. The data obtained in this study allows for simulations and the analysis of the behavior of microplastics once in the environment to predict future settlements. The DSC showed us the melting temperatures of PP, PE, PET, and PS, the Pyr-GC/MS showed the fragmentation patterns, and the presence of these MPs in the samples was confirmed
Garantías del teletrabajador en el ordenamiento jurídico Colombiano frente a la pandemia COVID 19 Español
No full textThe present research work aims to analyze the guarantees of teleworkers in the Colombian legal system in the context of the COVID-19 pandemic. The legal regulation and current normative provisions for telework in Colombia are examined, with special emphasis on the guarantees provided to workers in this employment modality amid the health crisis. Aspects such as labor rights, health, and safety protection, working hours, remuneration, and social benefits for teleworkers are analyzed. Furthermore, the control and supervision mechanisms implemented to ensure compliance with rights and duties of both employers and workers in telework are explored. Through a legal and normative approach, this study seeks to supply a detailed analysis of the existing guarantees in the Colombian legal system for teleworkers and their adaptation in the face of the health emergency caused by the COVID-19 pandemic. The findings and conclusions of this study will contribute to the academic and legal debate about the rights and protection of teleworkers in Colombia during times of crisis and changes in the labor landscapeEl presente trabajo de investigación tiene como objetivo analizar las garantías del teletrabajador en el ordenamiento jurídico colombiano en el contexto de la pandemia de COVID-19. Se examina la regulación legal y las disposiciones normativas vigentes para el teletrabajo en Colombia, con especial énfasis en las garantías que se brindan a los trabajadores en esta modalidad laboral en medio de la crisis sanitaria. Se analizan aspectos como los derechos laborales, la protección de la salud y seguridad, la jornada laboral, la remuneración y los beneficios sociales para los teletrabajadores. Además, se exploran los mecanismos de control y supervisión implementados para garantizar el cumplimiento de los derechos y deberes tanto de los empleadores como de los trabajadores en el teletrabajo. A través de un enfoque jurídico y normativo, se busca brindar un análisis detallado de las garantías existentes en el ordenamiento jurídico colombiano para los teletrabajadores y su adaptación frente a la emergencia sanitaria causada por la pandemia de COVID-19. Los hallazgos y conclusiones de este estudio contribuirán al debate académico y jurídico en torno a los derechos y protección de los teletrabajadores en Colombia durante situaciones de crisis y cambios en el ámbito laboral.Lista De Tablas Y Figuras 10 --
Introducción 11 --
Capítulo I 13 --
Planteamiento Del Problema 13 --
Formulación Del Problema 15 --
Objetivos 15 --
Objetivo General 15 --
Objetivos Específicos 15 --
Justificación 15 --
Delimitación 16 --
Espacial 16 --
Temporal 16 --
Línea de investigación 16 --
Sublínea de investigación 17 --
Capitulo II 18 --
Marco Teórico 18 --
Antecedentes De La Investigación 18 --
Bases teóricas 28 --
Garantías Jurídicas 45 --
Pandemia COVID 19 Vs Teletrabajo 51 --
Capitulo III 54 --
Metodología 54 --
Corte De La Investigación 55 --
Enfoque De La Investigación 56 --
Método 57 --
Paradigma De La Investigación 58 --
Nivel ¡Error! Marcador no definido.
Técnica De Recolección De Datos 59 --
Análisis Y Discusión De Resultados 6
Conclusiones 74 --
Referencias Bibliográficas 76 --
Jurisprudencia 78 --
Anexos 79 --Abogado(a)Pregrad
Comparison of visual skills between federated and non-federated athletes
No full textBackground: To perform motor tasks, athletes must gather a considerable amount of visual information quickly. Evidence shows that visual skills vary between athletes and non-athletes, and impact athletic performance. However, there is no scientific evidence suggesting that there are any differences between the visual skills of federated and non-federated athletes. As such, the objective of this paper was to compare how visual skills influence the sports performance of federated and non-federated athletes, respectively. Methods: A visual examination has been conducted on a total of 52 athletes between 18 and 37 years of age. The COI-Sport Vision system screen (International Optometry Center, Madrid, Spain) was used to examine static visual acuity, dynamic visual acuity, contrast sensitivity, stereopsis, fixation disparity, visual memory, identification, anticipation time, peripheral awareness, and hand-eye coordination. Results: On average, federated athletes train more hours per day than non-federated athletes (1.4 ± 0.8) (p = 0.046). A significant correlation was observed between the average time of visual memory (β = −0.0683, p < 0.001), the average time of anticipation (β = 0.006, p = 0.009), the average time of peripheral awareness (β = 0.026, p = 0.002), hand-eye coordination (β = 0.028, p = 0.004), dynamic visual acuity (β = 0.055, p < 0.001), and the number of training hours. Conclusion: Results suggest that federated athletes are more concerned about their ocular health. Nonetheless, no differences were found in the oculomotor skills of both groups. Further investigation is required to consider each sport discipline individually
Recovery of (z)-13-docosenamide from industrial wastewater and its application in the production of virgin polypropylene to improve the coefficient of friction in film type applications
No full textAdditives play an important role in the production of plastic materials through their application, in which the mechanical, thermal, and physical properties of polymers are improved, making them last longer and be more resistant. During the synthesis of polypropylene resins, the remains of additives that are not absorbed by the resin are removed in the purification stage and end up in the wastewater. In this article, the recovery of (Z)-13-docosenamide from the wastewater from the process, its purification, and its application in the process was carried out. For the extraction of the additive, solid phase extraction (SPE) was used, and to guarantee the purity of (Z)-13-docosenamide, techniques such as high performance liquid chromatography (HPLC), Fourier transform infrared (FTIR), gas chromatography-mass spectrometry (GC/MS), thermogravimetric (TG) coupled with a gas chromatography-mass spectrometry (GC/MS), and differential scanning calorimetry (DSC) were used. The recovered erucamide was added to the PP between 0.05 and 0.3% w/w. The effects of the properties of the virgin polypropylene with the recovered additive were also evaluated to determine its effectiveness in improving the properties of the material by measuring the coefficient of friction (CoF) as well as the mechanical properties and wettability through atomic force microscopy (AFM) and the contact angle, respectively. It was discovered that using these techniques, it is possible to recover approximately 95% of the additive present in the water while keeping the material’s properties within the desired limits
A novel, highly potent nadph-dependent cytochrome P450 reductase from waste liza klunzingeri liver
No full textThe use of marine enzymes as catalysts for biotechnological applications is a topical subject. Marine enzymes usually display better operational properties than their animal, plant or bacterial counterparts, enlarging the range of possible biotechnological applications. Due to the fact that cytochrome P450 enzymes can degrade many different toxic environmental compounds, these enzymes have emerged as valuable tools in bioremediation processes. The present work describes the isolation, purification and biochemical characterization of a liver NADPH-dependent cytochrome P450 reductase (CPR) from the marine fish Liza klunzingeri (LkCPR). Experimental results revealed that LkCPR is a monomer of approximately 75 kDa that is active in a wide range of pH values (6–9) and temperatures (40–60 °C), showing the highest catalytic activity at pH 8 and 50 °C. The activation energy of the enzyme reaction was 16.3 kcal mol−1 K−1. The KM values for cytochrome C and NADPH were 8.83 μM and 7.26 μM, and the kcat values were 206.79 s−1 and 202.93 s−1, respectively. LkCPR displayed a specific activity versus cytochrome C of 402.07 µmol min−1 mg1, the highest activity value described for a CPR up to date (3.2–4.7 times higher than the most active reported CPRs) and showed the highest thermostability described for a CPR. Taking into account all these remarkable catalytic features, LkCPR offers great potential to be used as a suitable biocatalyst
Effectiveness of deep brain stimulation in refractory and drug-resistant aggressiveness in autism spectrum disorder
No full textBackground. Aggressive behavior, resistant to pharmacological and psychological treatment, is observed in some cases of autism. The main objective of this study is to analyze the efficacy of deep brain stimulation (DBS) for aggressive behavior in severe autism. Method. The effectiveness of DBS was analyzed in a clinical follow-up of 5 autistic patients, with impaired functional activity and refractoriness to psychopharmacological and behavioral treatment. The patients were examined in medical meetings and evaluated by experienced professionals using the Overt Aggressiveness Scale (OAS), before surgical implantation and after 6, 12 and, 18 months of follow-up. Student's t-test analyses were performed to assess changes in aggressiveness scores. The effect size of surgical intervention on patients' OAS performance was estimated. Results. Before the intervention, patients scored very high on the aggressiveness scale. In the subsequent medical controls, a clinically and psychometrically significant decrease in aggressiveness and self-injury symptoms was observed. These data were confirmed by the parents up to 18 months of follow-up. Very large effect sizes were obtained in favor of DBS. Conclusions. In this case series, DBS significantly reduced aggressiveness and self-injury, favoring functionality, social adaptation of the patients, and improving the quality of life of the family. We believe that DBS may be a viable treatment option
Characterisation of youth entrepreneurship in Medellín-Colombia using machine learning
No full textThe aim of this paper is to identify profiles of young Colombian entrepreneurs based on data from the “Youth Entrepreneurship” survey developed by the Colombian Youth Secretariat. Our research results show five profiles of entrepreneurs, mainly differentiated by age and entrepreneurial motives, as well as the identification of relevant skills, capacities, and capabilities for entrepreneurship, such as creativity, learning, and leadership. The sample consists of 633 young people aged between 14 and 28 years in Medellín. The data treatment was approached through cluster analysis using the K-means algorithm to obtain information about the underlying nature and structure of the data. These data analysis techniques provide valuable information that can help to better understand the behaviour of Colombian entrepreneurs. They also reveal hidden information in the data. Therefore, one of the advantages of using statistical and artificial intelligence techniques in this type of study is to extract valuable information that might otherwise go unnoticed. The clusters generated show correlations with profiles that can support the design of policies in Colombia to promote an entrepreneurial ecosystem and the creation and development of new businesses through business regulation
El impacto causado por la crisis sanitaria covid-19 en los establecimientos de comercio ubicados en la zona cordialidad en Sabanalarga-Atlántico periodo 2021 -2022
No full textEste estudio, fue realizado a través de un enfoque mixto Cuantitativo-Cualitativo), mediante instrumentos como entrevista, bases de datos y encuestas que determinó el impacto o los efectos causado por el covid-19 en los establecimientos de comercios ubicados la zona cordialidad en Sabanalarga-Atlántico periodo 2021 – 202. Se logró determinar que la zona la coordinadora en Sabanalarga Atlántico se presentaron impactos negativos tanto sociales, como económicos por la crisis sanitaria ocasionada por el virus llamado Covid 19. Entre estos impactos se evidenció repercusiones en la unidad productiva y operatividad de los establecimientos de comercios. Así mismo; se logró constatar, que la protección aplicada por la administración Municipal para disminuir los impactos generados por el Covid 19 en la unidad productiva del establecimiento de comercio, hace falta una gestión pertinente, además de políticas estatales que garanticen los derechos a los comerciantes. A pesar de que la administración municipal implemento medidas y control para mitigar el virus del covid-19, no se compró la implementación de acciones, estrategias o actividades que directamente beneficien a todos los comerciantes o propietarios de los establecimientos de comercio.This study was carried out through a mixed Quantitative-Qualitative approach), using instruments such as interviews, databases and surveys that prolonged the impact or effects caused by covid-19 in business establishments located in the cordiality area. in Sabanalarga -Atlántico period 2021 – 202. It will be determined that the area of the coordinator in Sabanalarga Atlántico will have negative social and economic impacts due to the health crisis caused by the virus called Covid 19. Among these impacts, repercussions on the productive unit were evidenced and operation of commercial establishments. In addition; It is verified that the protection applied by the municipal administration to reduce the impacts generated by Covid 19 in the productive unit of the commercial establishment, requires a pertinent management, in addition to state policies that guarantee the rights of merchants. Despite the fact that the municipal administration implemented measures and control to mitigate the covid-19 virus, the implementation of actions, strategies or activities that directly benefit all merchants or owners of commercial establishments was not purchased.Lista de Tablas y Figuras 10 -- Capítulo I 11 -- Planteamiento Del Problema 11 -- Pregunta Problema 15 -- Objetivos 15 -- Objetivo General 15 -- Objetivo Específico 15 -- Justificación 16 -- Delimitación 18 -- Espacial 18 -- Temporal 18 -- Científica 18 -- Paradigma de la Investigación 18 -- Corte De La Investigación (Exploratorio Consecuencial) 19 -- Capitulo II 19 -- Antecedentes 20 -- Marco Teórico 26 -- El Coronavirus (Covid-19) 26 -- Situación Económica De Colombia En Medio Del Covid-19. 27 -- Establecimientos De Comercio 29 -- Impacto Causado Por La Crisis Sanitaria Del Covid --19 En Los Establecimientos De Comercio 30 -- Impactos Generados Por La Crisis Sanitaria Del Covid-19 En La Unidad Productiva Y Operatividad De Los Establecimientos De Comercios 32 -- Marco Geográfico 32 -- Marco Normativo 34 -- Normas A Nivel Internacional 34 -- Normas A Nivel Nacional: 35 -- Capitulo III 46 -- Marco Metodológico 46 -- Tipo de Investigación 47 -- Enfoque de la Investigación 47-- Población 48 -- Muestra 48 -- Recolección de los Datos 49 -- Participantes 50 -- Capitulo IV 52 -- Resultados 52 -- Análisis de Datos Cuantitativos 52 -- Encuesta 52 -- Base De Datos De Los Establecimientos De Comercio Cancelados En Sabanalarga 61 -- Análisis De Datos Cualitativos 64 -- Conclusiones 76 -- Referencias 80 -- Anexos 90--Abogado(a)Pregrad
El cuento como estrategia pedagógica para el desarrollo de la comprensión lectora de los estudiantes del Municipio de El Banco Magdalena – Colombia
No full textEl desarrollo de las competencias lectoras en los estudiantes resulta un desafío para el sistema educativo y todos los actores involucrados. Desde ese referente la presente investigación tuvo como objetivo: Analizar el efecto del cuento en el desarrollo de la comprensión lectora de los estudiantes de básica primaria. La investigación se sustentó en el paradigma empírico analítico como eje central de su ejecución, bajo un enfoque cuantitativo y un diseño cuasi experimental, con la selección de una muestra de 45 estudiantes pertenecientes al grado de 3° de básica primaria de la Institución Educativa Arcesio Cáliz Amador, del municipio de El Banco Magdalena, Colombia; a quienes se les aplicó un pret-test con el fin de establecer un parámetro inicial frente al nivel de competencia lectora y finalmente se aplicó un post-test para lograr medir la variable dependiente y el impacto de la estrategia pedagógica. Como resultado, los promedios obtenidos por los estudiantes durante la aplicación del post-test, evidenciaron un incremento en la comprensión lectora, comparados con la prueba inicial. Se concluye que el cuento es una excelente estrategia para fortalecer la comprensión lectora, ya que un estudiante motivado y con interés en la lectura puede lograr aprendizajes significativos que le permitan desarrollar los componentes lectores como son el Semántico, Sintáctico y Pragmático.The development of reading skills in students poses a challenge for the educational system and all involved stakeholders. With this context in mind, the present research aimed to analyze the effect of storytelling on the development of reading comprehension in elementary school students. The research was grounded in the empirical-analytical paradigm as the central axis of its execution, utilizing a quantitative approach and a quasi-experimental design. A sample of 45 students from the 3rd grade of elementary school at the Arcesio Cáliz Amador Educational Institution in El Banco, Magdalena, Colombia, was selected. A pre-test was administered to establish an initial parameter regarding their level of reading competence, followed by a post-test to measure the dependent variable and the impact of the pedagogical strategy. As a result, the averages obtained by the students during the post-test application showed an increase in reading comprehension compared to the initial test. It is concluded that storytelling is an excellent strategy to strengthen reading comprehension, as a motivated student with an interest in reading can achieve significant learning that allows them to develop reading components such as the Semantic, Syntactic, and Pragmatic aspectsIntroducción 14-- Planteamiento del problema 16-- Descripción del problema 16-- Formulación del problema 22-- Preguntas Especificas 22-- Hipótesis23-- Objetivos 24-- Objetivo General 24-- Objetivos Específicos 24—Justificación 25-- Delimitación 27-- Delimitación espacial 27-- Delimitación temporal 27-- Delimitación temática 27-- Marco teórico 29-- Antecedentes de la Investigación 29-- Antecedentes Internacionales 29--Antecedentes Nacionales 34-- Antecedentes Locales 39-- Fundamentación Teórica- Conceptual 44-- Lectura 44-- Comprensión lectora 47-- El cuento 49-- Marco legal 50-- Definición de variables 51-- Definición Conceptual 51-- Operacionalización de variables 52-- Marco metodológico 56-- Paradigma de investigación 56-- Enfoque de la investigación 56-- Tipo de la Investigación 57-- Diseño de la Investigación 57-- Población y muestra 58-- Población 58-- Muestra 58-- Técnicas e Instrumentos de Recolección de Datos 59-- Técnicas 59--Procedimientos en la aplicación del instrumento 60—Discusión 72—Conclusiones 73-- Recomendaciones 83—Referencias 84--Magíster en Administración Modalidad VirtualMaestrí
Estrategias educativas digitales y su incidencia en la resolución de problemas matemáticos en estudiantes de básica primaria en escuelas rurales
No full textLa presente investigación tuvo como finalidad evidenciar la incidencia que tiene la estrategia mediada por las TIC Capsulas educativas digitales en la resolución de problemas aritméticos en el área de las matemáticas en los estudiantes de grado quinto (5°) del Centro educativo del Rubí, del municipio de la Macarena, Meta esto con el fin de poder fortalecer el proceso de aprendizaje de los estudiantes en las matemáticas. La investigación se realiza bajo un paradigma positivista con un enfoque cuantitativo de tipo descriptivo con un diseño cuasi experimental y transversal. Se seleccionó una muestra de 50 estudiantes de grado quinto (5°) donde a los docentes de este grado se les aplicó una ficha de observación para identificar si en él, proceso de enseñanza aprendizaje utilizaban una mediación TIC para fortalecer sus aprendizajes, luego se implementa un Pre-Test para determinar el nivel de resolución de problemas aritméticos de los estudiantes, a partir de esto se aplica la estrategia mediada por las TIC Capsulas educativas Digitales durante un periodo escolar, por último los estudiantes realizan un Post – test para determinar la incidencia que tuvo la estrategia TIC en la resolución de problemas aritméticos en los estudiantes. Por último, se logra evidenciar en los resultados que la estrategia mediada por las TIC Capsulas Educativas Digitales, fue muy pertinente al momento de fortalecer la resolución de problemas matemáticos en los estudiantes de grado quinto del centro educativo el rubí, logrando evidenciar un avance significativo en sus aprendizajes.The purpose of this research was to demonstrate the impact of the strategy mediated by digital educational capsules using ICT (Information and Communication Technology) on the resolution of arithmetic problems in fifth-grade students at a rural educational center. The research was conducted under a positivist paradigm with a quantitative, quasi-experimental, descriptive, crosssectional, and field approach. A sample of 50 fifth-grade students was selected. An observation form was used to identify the teaching process carried out by the teachers and whether they used ICT mediation to enhance learning. Subsequently, a Pre-Test was administered to determine the level of arithmetic problem-solving skills among the students. Based on this, the strategy mediated by digital educational capsules using ICT was implemented during a school period. Finally, the students took a Post-Test to determine the impact of the ICT strategy on the resolution of arithmetic problems in the students. In the analysis of the results obtained, it is evident that the strategy mediated by digital educational capsules using ICT had a positive impact on fifth-grade students at the El Rubí educational center, demonstrating a significant improvement in the development of arithmetic problem-solving skills.Lista de Figuras y tablas 11—Introducción 13-- Capítulo I 15-- Problema de investigación 15-- Planteamiento del problema 15-- Formulación del problema 23—Objetivos 24-- Objetivo general 24-- Objetivos específicos 24—Justificación 25-- Delimitación del problema 27-- Delimitación espacial y demográfica 27-- Delimitación temporal 27-- Hipótesis del proyecto de investigación 28-- Hipótesis: 28-- Hipótesis nula 28-- Hipótesis alternativa: 28-- Capitulo II 29-- Marco referencia 29—Antecedentes 30-- Antecedentes Internacionales: 30-- Antecedentes Nacionales: 33-- Constructivismo 48-- Aprendizaje autónomo 53-- Marco Legal 55-- Marco conceptual 58-- Operacionalización de las variables 59-- Capitulo III 63-- Diseño metodológico 63-- Paradigma de la investigación 63-- Enfoque de la investigación 64-- Tipo de investigación 65-- Diseño de investigación 66—Población 67—Muestra 67-- Técnica de recolección de datos 68-- Instrumento de recolección de datos 69-- Capitulo IV 71—Resultado 71-- Análisis de los resultados cada uno de los instrumentos en la recolección de datos del proyecto de investigación 71-- Técnica observación e instrumento ficha de observación 71-- Técnica Test, instrumento prueba de conocimiento Icfes 72-- Análisis Post – Test 78-- Discusión de los resultados de la investigación 84—Conclusiones 86 –Dificultades 87-- Futuras investigaciones 88 –Recomendaciones 88—Referencia 90—Anexos 98--Magíster en EducaciónMaestrí