39 research outputs found
Viscoelastic and thermal characterization of crosslinked PVC
No full textSoft PVC is employed for the manufacturing of a wide range of products with different properties and a relatively low
cost. The utilization of soft PVC is restricted by the poor thermal, chemical and mechanical resistance properties. Also,
plasticizer migration can modify the properties or can make useless the materials for some applications because of toxicity
or a general loss of properties. PVC crosslinking is the most effective way to improve mechanical and transport properties
of rigid or flexible PVC at high temperatures, but at the same time the thermal stability of PVC may be significantly
reduced. In this work, the crosslinking reaction of plasticized poly(vinyl chloride) (PVC) through difunctional amines
was studied. The mechanisms involved in the crosslinking reaction were explained by Fourier transform infrared (FTIR)
analysis. The thermal activated crosslinking reaction was studied by cone and plate rheometry, analyzing the evolution of
viscoelastic properties of the suspension as a function of time and temperature. The effect of the addition of crosslinking
agents on the thermal stability of the polymer was studied by thermogravimetric analysis (TGA), which revealed that
crosslinking reactions promote thermal degradation phenomena in the polymer matrix. This is attributed to the formation
of HCl and other species promoting polymer degradation during crosslinking, thus leading to higher weight loss during
thermal treatment with respect to unmodified PVC plastisols. This was also confirmed by an evident yellowing after crosslinking, especially at higher temperatures
Hemispheric dominance and language proficiency levels in the four macro skills of Western Mindanao State university college students
No full textThis study was conducted to determine the relationship between the hemispheric dominance (HD) and the English proficiency (EP) scores in the four macro skills of the Western Mindanao State University college students. It hypothesized that students’ HD would have a significant correlation a) with their EP scores in listening, speaking, reading and writing, b) with their global EP score, c) with both the macro and global scores when respondents would be grouped according to age, gender and area of specialization. In this study, there were 240 respondents selected through purposive, stratified, and random sampling techniques from the 5,096 students of the Colleges of Arts and Sciences, Engineering and Education. Using the standardized HD Test, the standardized Listening and Reading Comprehension Tests, the researcher-made Speaking and Writing Skill Tests and Cloze Test and employing mainly the Pearson r for the statistical analysis, the study concluded: 1) that most of the students of the Colleges of Arts and Sciences, Engineering and Education of Western Mindanao State University were left-brained (74.6%); 2) that the students were “good” in speaking, “fair” in listening and writing skills but “ poor” in reading and in global English; 3) that there was no significant relationship between the students’ hemisphericity and their EP scores in listening, speaking, reading, writing and global proficiency tests; and 4) that a significant relationship was shown between HD and EP scores when respondents were grouped according to age and area of specialization only.hemisphericity, language performance, English, hemispheric dominance, right brain, left brain, whole brain, speaking, listening, reading, writing
Decay pathways for protonated and deprotonated adenine molecules
No full textThis article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Journal of Chemical Physics 151.4 (2019): 044306 and may be found at https://aip.scitation.org/doi/abs/10.1063/1.5109963We have measured fragment mass spectra and total destruction cross sections for protonated and deprotonated adenine following collisions with He at center-of-mass energies in the 20-240 eV range. Classical and ab initio molecular dynamics simulations are used to provide detailed information on the fragmentation pathways and suggest a range of alternative routes compared to those reported in earlier studies. These new pathways involve, for instance, losses of HNC molecules from protonated adenine and losses of NH2 or C3H2N2 from deprotonated adenine. The present results may be important to advance the understanding of how biomolecules may be formed and processed in various astrophysical environmentsThis work was supported by the Swedish Research Council (Constant Nos. 2017-00621, 2015-04990, 2016-04181, and 2018-04092). Furthermore, we acknowledge the European Joint on Theoretical Chemistry and Computational Modelling (INT-EJD-TCCM). We acknowledge the generous allocation of computer time at the Centro de Computacion Cientifica at the Universidad Autonoma de Madrid (CCC-UAM). This work was partially supported by Project No. CTQ2016-76061-P of the Spanish Ministerio de Economia y Competitividad (MINECO
Environmental-dependent proline accumulation in plants living on gypsum soils
No full text[EN] Biosynthesis of proline¿or other compatible solutes¿is a conserved response of all organisms to different abiotic stress conditions leading to cellular dehydration. However, the biological relevance of this reaction for plant stress tolerance mechanisms remains largely unknown, since there are very few available data on proline levels in stress-tolerant plants under natural conditions. The aim of this work was to establish the relationship between proline levels and different environmental stress factors in plants living on gypsum soils. During the 2-year study (2009¿2010), soil parameters and climatic data were monitored, and proline contents were determined, in six successive samplings, in ten taxa present in selected
experimental plots, three in a gypsum area and one in a semiarid zone, both located in the province of Valencia, in south-east Spain. Mean proline values varied significantly between species; however, seasonal variations within species
were in many cases even wider, with the most extreme differences registered in Helianthemum syriacum (almost 30 lmol g-1 of DW in summer 2009, as compared to ca. 0.5 in spring, in one of the plots of the gypsum zone). Higher proline contents in plants were generally observed under lower soil humidity conditions, especially in the
2009 summer sampling preceded by a severe drought period. Our results clearly show a positive correlation between the degree of environmental stress and the proline level in most of the taxa included in this study, supporting a functional role of proline in stress tolerance mechanisms of plants adapted to gypsum. However, the main trigger of proline biosynthesis in this type of habitat, as in arid or semiarid zones, is water deficit, while the component of ¿salt stress¿ due to the presence of gypsum in the soil only plays a secondary role.This work has been supported by the Spanish Ministry of Science and Innovation (Project CGL2008-00438/BOS), with contribution from the European Regional Development Fund.Boscaiu, M.; Bautista Carrascosa, I.; Lidón Cerezuela, AL.; Llinares Palacios, JV.; Lull, C.; Donat-Torres, M.; Mayoral García-Berlanga, O.... (2013). Environmental-dependent proline accumulation in plants living on gypsum soils. 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Not Bot Horti Agrobo 39(1):18–23Mota JF, Sánchez Gómez P, Merlo Calvente ME, Catalán Rodríguez P, Laguna Lumbreras E, de la Cruz Rot M, Navarro Reyes FB, Marchal Gallardo F, Bartolomé Esteban C, Martínez Labarga JM, Sainz Ollero H, Valle Tendero F, Serra Laliga L, Martínez Hernández F, Garrido Becerra JA, Pérez García FJ (2009) Aproximación a la checklist de los gipsófitos ibéricos. Anales de Biología 31:71–80Murakeözy ÉP, Nagy Z, Duhazé C, Bouchereau A, Tuba Z (2003) Seasonal changes in the levels of compatible osmolytes in three halophytic species of inland saline vegetation in Hungary. J Plant Physiol 160:395–401Nelson DW, Sommers LE (1982) Total carbon, organic carbon, and organic matter. In: Page AL et al (eds) Methods of soil analysis, part 2: chemical and microbiological properties. Soil Science Society of America, Madison, pp 539–577Palacio S, Escudero A, Montserrat-Martí G, Maestro M, Milla R, Albert M (2007) Plants living on gypsum: beyond the specialist model. 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El foro de Los Bañales (conventus Caesaraugustanus): arquitectura, fases y programas decorativos
No full textThis article is a comprehensive study of the forum of Los Bañales de Uncastillo (conventus Caesaraugustanus). Thanks to the latest archaeological excavations, we know the complete architectural plan. It is articulated around a small square with a π-shaped portico (porticus triplex) opens on the north, east and west sides. Each of the buildings is analysed in detail: the basilica forensis, the curia, the scholae and the south area. Even if the complex was built in the Augustan period, several architectural phases have been documented. We can underline a major renovation phase during the Flavian period that it must be linked with the legal status change of the city into a municipium. The article is a comprehensive study about its epigraphic landscape, sculptural programme and its architectural decoration.En este artículo se realiza un estudio integral del foro de Los Bañales de Uncastillo (conventus Caesaraugustanus). Gracias a las últimas campañas de excavaciones arqueológicas se conoce la totalidad de la planta arquitectónica del conjunto, articulada en torno a una pequeña plaza a la que se abre un tripórtico en π (porticus triplex) en los lados norte, este y oeste. Se analizan en detalle cada uno de sus edificios: la basilica forensis, la curia, las scholae y los recintos de la zona sur. El conjunto fue construido en época augustea, aunque tuvo varias fases arquitectónicas con una importante reforma en época flavia, coincidiendo con la promoción jurídica de la ciudad a municipium. Se estudian además los programas epigráficos, escultóricos y su decoración arquitectónica
El proceso monitorio como mecanismo de descongestión judicial
No full textEl proceso monitorio es un proceso declarativo especial, donde se parte de una
afirmación por parte del acreedor demandante. Con base en esa afirmación, de
que existe un derecho de crédito, el juez profiere un requerimiento de pago y es allí
donde se abre la oportunidad del derecho de contradicción del deudor demandado,
cuya finalidad es que el acreedor demandante, obtenga el justo título que le
permitirá cobrar posteriormente la obligación. El título ejecutivo está contenido en la
sentencia monitoria y es en esta donde el juez declara o decreta la existencia de la
obligación del deudor demandado.
La tutela rápida del crédito a través del proceso monitorio según el ICDP, es
considerado como un mecanismo célere y eficaz para acercar al ciudadano de a
pie, al tendero, al de la plaza de mercado a la administración de justiciaUniversidad Libre de Colombia--Facultad de Derecho -- DerechoThe payment procedure is a special declarative process, where it is part of a
statement by the applicant creditor. Based on that statement , that there is a credit
claim , the judge utters a payment and that is where the opportunity of the right of
opposition by the defendant debtor opens, whose purpose is that applicant
creditor, obtain the right title will allow later assume the obligation. The executive
title is contained in the monitoring practice is in this sentence and where the judge
declares or decrees the existence of the obligation of the defendant debtor.
Rapid credit protection through the payment process by ICDP, is considered as a
very swift and effective mechanism to bring the ordinary citizen, the shopkeeper,
the market square of the administration of justice
Gestión de las tiendas de barrio en Colombia
No full textEl presente artículo plasma de manera detallada información importante acerca de cómo es el funcionamiento y gestión de las tiendas de barrio en Colombia, esta investigación nos da a demostrar cómo es la vida del tendero, como son sus clientes, como es la vida de aquellos estratos bajos que se localizan en cada parte de Colombia, como en su comercio y por ultimo pero no menos importante como están realmente las tiendas de Colombia en el presente, las tiendas de barrio se han creado como respuesta aquellas necesidades de personas que necesitan un producto cercano y económico, a su vez se crean como respuesta a la falta de oportunidades que tienen las personas que deciden comenzar su emprendimiento creando una tienda en una esquina de su vivienda. Los resultados de estos artículos muestran que para poder sobrevivir en el mercado es necesario crear alternativas que le ayuden a superar la realidad a la que hoy se enfrentan, ya que para la mayoría de sus consumidores son de vital importancia y la requieren como una solución para su calidad de vida.This article provides detailed information about how the operation and management of neighborhood stores in Colombia is, this research allows us to demonstrate what the life of the shopkeeper is like, what their customers are like, what the life of those strata is like. low that are located in each part ofColombia, as is its trade and last but not least how are the stores in Colombia in the present, the neighborhood stores have been created as a response to those needs of people who need a nearby product and economic, in turn, are created as a response to the lack of opportunities that people who decide to start their business have by creating a store in a corner of their home. The results of these articles show that in order to survive in the market it is necessary to create alternatives that help you overcome the reality you are facing today, since for most of your consumers they are of vital importance and require it as a solution to your quality of life.PregradoAdministrador de NegociosSedes::Cartagena::Línea de investigación emprendimiento y desarrollo organizacional (Cartagena
Design of a technical training program for young people in the textile sector in the city of Cúcuta
No full textDigitalEl presente trabajo aborda la problemática del desempleo juvenil en Cúcuta mediante el diseño de un programa de formación técnica en el sector textil. La investigación adopta un enfoque cualitativo descriptivo, sustentado en el análisis de fuentes secundarias como datos del DANE, planes de desarrollo municipal y departamental. El diagnóstico socioeconómico revela que Cúcuta enfrenta una tasa de desempleo juvenil del 27,1% y una informalidad laboral de la tasa de desempleo juvenil del 27,1% y una informalidad laboral del 63,8% (Departamento Nacional de Planeación, 2024), factores que limitan las oportunidades de desarrollo de los jóvenes.
El programa propuesto integra un modelo teórico-práctico basado en la metodología de modelación de Deroncele, estructurado en cuatro módulos: formación básica en diseño textil, desarrollo técnico (patronaje, escalado y confección), gestión de calidad y emprendimiento, y práctica aplicada en talleres reales.
Adicionalmente, se diseñan estrategias de inserción laboral que incluyen módulos de empleabilidad, alianzas empresa-educación, orientación vocacional digital e incentivos al emprendimiento juvenil. Los resultados evidencian que la formación técnica especializada, articulada con el sector productivo local y acompañada de estrategias efectivas de inserción laboral, constituye una herramienta transformadora para reducir el desempleo juvenil, fortalecer la competitividad empresarial y promover el desarrollo económico sostenible del municipio. El programa busca convertir el bono demográfico juvenil en un activo productivo que contribuya a la cohesión social y al fortalecimiento del tejido empresarial cucuteño.
El programa propuesto integra un modelo teórico-práctico basado en la metodología de modelación de Deroncele, estructurado en cuatro módulos: formación básica en diseño textil, desarrollo técnico (patronaje, escalado y confección), gestión de calidad y emprendimiento, y práctica aplicada en talleres reales.
Adicionalmente, se diseñan estrategias de inserción laboral que incluyen módulos de empleabilidad, alianzas empresa-educación, orientación vocacional digital e incentivos al emprendimiento juvenil. Los resultados evidencian que la formación técnica especializada, articulada con el sector productivo local y acompañada de estrategias efectivas de inserción laboral, constituye una herramienta transformadora para reducir el desempleo juvenil, fortalecer la competitividad empresarial y promover el desarrollo económico sostenible del municipio. El programa busca convertir el bono demográfico juvenil en un activo productivo que contribuya a la cohesión social y al fortalecimiento del tejido empresarial cucuteño.This study addresses the problem of youth unemployment in Cúcuta by designing a technical training program in the textile sector. The research adopts a descriptive qualitative approach, based on the analysis of secondary sources such as data from the National Administrative Department of Statistics (DANE), and municipal and departmental development plans. The socioeconomic diagnosis reveals that Cúcuta faces a youth unemployment rate of 27.1% and an informal employment rate of 63.8% (National Planning Department, 2024), factors that limit young people's development opportunities.
The proposed program integrates a theoretical-practical model based on Deroncele's modeling methodology, structured in four modules: basic training in textile design, technical development (pattern making, grading, and garment construction), quality management and entrepreneurship, and applied practice in real workshops.
Additionally, job placement strategies are designed, including employability modules, business-education partnerships, digital career guidance, and incentives for youth entrepreneurship. The results demonstrate that specialized technical training, linked to the local productive sector and accompanied by effective job placement strategies, is a transformative tool for reducing youth unemployment, strengthening business competitiveness, and promoting the sustainable economic development of the municipality. The program aims to transform the youth demographic dividend into a productive asset that contributes to social cohesion and strengthens the business fabric of Cúcuta.Introducción .................................................................................................................................. 16
Problema ....................................................................................................................................... 17
Pregunta de Investigación ............................................................................................................. 17
Planteamiento del Problema ......................................................................................................... 17
Objetivos ....................................................................................................................................... 20
Objetivo General ........................................................................................................................... 20
Objetivos Específicos.................................................................................................................... 20
Justificación .................................................................................................................................. 20
Marco Teórico ............................................................................................................................... 23
Desempleo Juvenil en Colombia .................................................................................................. 23
Desempleo Juvenil en Cúcuta ....................................................................................................... 26
Métodos de Aprendizaje por Competencias Laborales ................................................................ 28
Habilidades Blandas...................................................................................................................... 28
Formación por Competencias ....................................................................................................... 29
Estrategia Educativa que une Teoría y Práctica para un Aprendizaje Efectivo ............................ 32
Estrategia de Inserción Laboral .................................................................................................... 34
Fundamentos Teóricos de la Formación Técnica en el Sector Textil ........................................... 35
Metodología .................................................................................................................................. 37
Entregables .................................................................................................................................... 41
Desarrollo ...................................................................................................................................... 41
Diagnóstico de la Situación Socioeconómica y Laboral del Municipio de Cúcuta ...................... 41
Situación Socioeconómica ............................................................................................................ 41
Situación Laboral .......................................................................................................................... 48
Sector Textil en Cúcuta ................................................................................................................. 52
Estructura del Programa de Formación Técnico-Practica ............................................................ 54
Componentes del Programa de Formación en el Sector Textil..................................................... 57
Formación Básica y Contextual del Diseño Textil ....................................................................... 57
Desarrollo Técnico (Patronaje, Escalado, Confección Artesanal – Industrial) ............................ 58
Gestión de Calidad y Emprendimiento ......................................................................................... 61
Practica Aplicada .......................................................................................................................... 63
Estrategia de Inserción Laboral .................................................................................................... 64
Conclusiones ................................................................................................................................. 70
Recomendaciones ......................................................................................................................... 72
Referencias Bibliográficas ............................................................................................................ 74EspecializaciónEspecialista en Administración de Proyecto
