Tesis de Grado
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Ítem A Class of Conservative Lagrangian-Eulerian Methods on Triangular Grids for Hyperbolic Problems : Design, Analysis and Applications(Universidad EAFIT, 2024) Agudelo Quiceno, Jorge Eliécer; Pérez Sepúlveda, John Alexander; Cano Sánchez, José AlbeiroIn this thesis, we construct, analyze and implement a class of fully-discrete and semi-discrete schemes on triangular grids intended to numerically solve initial value problems involving multidimensional hyperbolic conservation and balance laws, both scalar and systems. The construction of this novel class of schemes is based on the no-flow surface/curve concept and introduces an effective class of numerical fluxes that do not require constructing or evaluating the Jacobian matrix of the respective flux functions. The implementation of the new fully-discrete and semi-discrete Lagrangian-Eulerian schemes, , in the solution of nontrivial scalar and systems problems, is performed using a weak CFL-type stability condition that is independent of the eigenvalues (exact and approximate values) of the relevant Jacobian of the numerical flux functions, and without the need for high-resolution reconstruction procedures.Ítem A Novel Injectable Piezoelectric Hydrogel for Periodontal Disease Treatment.(Universidad EAFIT, 2023) Roldán Lopera, Lina María; Correa Vélez, Santiago AlbertoPeriodontal disease is a multifactorial, bacterially induced inflammatory condition characterized by the progressive destruction of periodontal tissues. The successful nonsurgical treatment of periodontitis requires multifunctional technologies offering antibacterial therapies and promotion of bone regeneration simultaneously. For the first time, in this study, an injectable piezoelectric hydrogel (PiezoGEL) was developed after combining gelatin methacryloyl (GelMA) with biocompatible piezoelectric fillers of barium titanate (BTO) that produce electrical charges when stimulated by biomechanical vibrations (e.g., mastication, movements). We harnessed the benefits of hydrogels (injectable, light curable, conforms to pocket spaces, biocompatible) with the bioactive effects of piezoelectric charges. A thorough biomaterial characterization confirmed piezoelectric fillers' successful integration with the hydrogel, photopolymerizability, injectability for clinical use, and electrical charge generation to enable bioactive effects (antibacterial and bone tissue regeneration). PiezoGEL showed significant reductions in pathogenic biofilm biomass (∼41%), metabolic activity (∼75%), and the number of viable cells (∼2-3 log) compared to hydrogels without BTO fillers in vitro. Molecular analysis related the antibacterial effects to be associated with reduced cell adhesion (downregulation of porP and fimA) and increased oxidative stress (upregulation of oxyR) genes. Moreover, PiezoGEL significantly enhanced bone marrow stem cell (BMSC) viability and osteogenic differentiation by upregulating RUNX2, COL1A1, and ALP. In vivo, PiezoGEL effectively reduced periodontal inflammation and increased bone tissue regeneration compared to control groups in a mice model. Findings from this study suggest PiezoGEL to be a promising and novel therapeutic candidate for the treatment of periodontal disease nonsurgically.Ítem A study of country reputation, corporate reputation, and international performance of Latin American companies(Universidad EAFIT, 2023) Parente Laverde, Ana María; Rojas de Francisco, Laura Isabel; Martins da Silva, IzaiasÍtem La actividad exportadora y el desempeño de las Pymes(Universidad EAFIT, 2017) Manotas Rodríguez, Eva Cristina; González Pérez, María AlejandraEsta disertación doctoral pretende dar una explicación a la relación entre la actividad exportadora de las pymes y el desempeño de éstas, desde la perspectiva de recursos y capacidades y con la aplicación de técnicas de investigación mixtas -- Para ello se presentan 4 artículos que reúnen los hallazgos obtenidos a través la modelación estadística y el análisis de 8 estudios de casos -- Dos trabajos corresponden al desarrollo metodológico de funciones hazard y el análisis de tasas de recurrencias, para evaluar el efecto de la actividad exportadora en el desempeño de las pymes -- Un tercer artículo corresponde al desarrollo de un modelo lineal generalizado para explicar el comportamiento de las exportaciones en función de los recursos y capacidades que reúnen y comprometen las pymes cuando desean intensificar su actividad exportadora -- Finalmente, el cuarto artículo presenta el análisis de 8 pymes estudios de caso, donde se identifican los recursos y capacidades que comprometen y desarrollan las pymes en cada una de las fases del proceso de internacionalización, y cómo este proceso y la adquisición y mejoramiento de recursos y capacidades han contribuido al buen desempeño de las empresas -- Los hallazgos evidencian la importancia de los recursos y capacidades de las pymes para poder desarrollar un exitoso proceso de actividad exportadora, y cómo este proceso, les ha permitido mejorar y adquirir nuevos recursos y capacidades que les genera ventaja competitiva -- Se destacan los conocimientos, experiencia y orientación emprendedora del emprendedor, como los recursos y capacidades que generan buen desempeño a las pymes exportadoras de mercados emergentesÍtem Actores sociales y acción organizada en un escenario neoliberal : el caso de emprendedores sociales en la ciudad de Medellín(Universidad EAFIT, 2021) Macías Prada, John Fernando; González Miranda, Diego RenéÍtem Aide à la décision en conception préliminaire par l'estimation des impacts environnementaux(Universidad EAFIT, 2016) Agudelo Gutiérrez, Lina María; Mejía Gutiérrez, Ricardo; Nadeau, Jean Pierre; Pailhes, JérômeÍtem Análisis de la influencia de las tecnologías de gerencia de las emociones en los procesos de subjetivación de empleados en organizaciones empresariales del departamento de Risaralda - Colombia(Universidad EAFIT, 2024) Muñoz Montaño, Juan Carlos; López Gallego, Francisco Darío; Jaramillo García, Óscar ArmandoÍtem Análisis de las perspectivas cosmopolitas sobre la interculturalidad: UNAOC y las alternativas hacia la comprensión de las dificultades para la convivencia global(Universidad EAFIT, 2016) Bustamante Zapata, Luís Fernando; Cuartas Restrepo, Juan ManuelÍtem Análisis de los conceptos biomédicos, experienciales y sociales de las personas con epilepsia, integrantes de la Fundación RenaSer con Amor de Medellín(Universidad EAFIT, 2024) Carrizosa Moog, Jaime; Cuartas Restrepo, Juan ManuelEpilepsy is a public health priority according to the World Health Organization. Despite achieving 70% control of the disease through medication, affected people report a poor quality of life. The objective of the research was to investigate, through drawing and narrative, the biomedical, experiential and social experience of epilepsy. The aim was to find a method that would elucidate the concepts that affect the daily lives of the affected people. Ideas of duality, splitting, dependence, prohibition, depression were captured in the drawing, as well as a counterpart of resilience, advocacy, diversity and a new lifestyle. The narrative obtained through semi-structured surveys demonstrated how the feeling of otherness begins with the experience of the epileptic seizure, and is reinforced with the attitudes one has towards the disease, from a personal and social point of view. The metaphorical use in the different descriptions demonstrated the persistence of belief in supernatural powers as the cause of epilepsy (sin, curse, witchcraft, etc.). Other concepts found about the experience of epilepsy are those of accident, travel, dictatorship, emptiness, unreality, restriction, loneliness, stigmatization and limitations. Positions of discovery of new options to balance the disease such as sports, reading, singing or open defiance of medical recommendations were also evident. Many of these concepts negatively impact the daily lives of people with epilepsy, and even their life plan. Several of these concepts are not usually addressed in medical consultation, limiting the possibility of guidance and intervention, and perpetuating the restriction of the full development of potentialities and rights. The results reinforce that the drawing and the semi-structured interview can be useful tools in the clinical context to clarify the biomedical, experiential and social aspects of epilepsy. New research and intervention options emerge, such as validation of these strategies; the possibility of timely intervention and respective evaluation by multidisciplinary teams in the area of health and human sciences, such as sociology, anthropology or social work; the extension of the research to caregivers and their immediate environment; and the recommendation to the medical team to take into account a comprehensive approach to the affected people.Ítem Análisis del cambio organizacional e institucional : estudio comparado de dos incubadoras de empresas : "Centro Integral de Servicios Empresariales (CREAME) en Medellín, Colombia (1996-2010) y Barcelona Activa, en Barcelona, España (1986-2010)"(Universidad EAFIT, 2012) Perdomo Charry, Geovanny; Rosas Castro, Jorge AlbertoEl trabajo explica el análisis del cambio organizacional e institucional de las incubadoras de empresas y como estudio de casos el de CREAME en Medellín, Colombia en el periodo de 1996 a 2010 y Barcelona Activa en Barcelona, España en el periodo de 1986 a 2010. Persigue explicar mediante el enfoque de investigación cualitativo el fenómeno organizacional complejo del cambio, constituido por un sistema social, técnico y dinámico, influido por factores externos e internos, así como por la medida en que las incubadoras logran institucionalizar las políticas y programas diseñados e implantados para desarrollar el campo del emprendimiento. Para analizarlo, interpretarlo y explicarlo, se construyó un marco teórico analítico multidisciplinario, basado en cinco perspectivas: el management para el estudio del campo del emprendimiento, la teoría de la organización para el análisis de los factores; la gobernanza para el análisis de las políticas y programas; la sociología de la organización, en cuanto al cambio organizacional y el nuevo institucionalismo sociológico para el análisis del cambio institucional. En la primera parte, los resultados indican que el cambio organizacional e institucional de las incubadoras ha sido coordinado externamente por el Sistema Nacional de Ciencia, tecnología e Innovación (SNCT&I) en Medellín, Colombia y el Sistema Nacional de Innovación (SNI) en Barcelona, España mediante políticas y programas de desarrollo empresarial, que en ocasiones no han generado una transformación de fondo. Por ello, la transformación de las incubadoras debe buscar el desarrollo institucional y la reinstitucionalización de procesos y acciones colectivas y cooperadas entre actores y sistemas para superar el cambio coercitivo, mimético y normativo, y procurar una configuración organizacional mixta y flexible. La segunda parte describe y analiza los dos estudios de caso que abordan cuatro etapas superpuestas: génesis, adolescencia, adultez y madurez. La recolección de las evidencias se construyó mediante la aplicación de entrevistas semiestructuradas a 20 actores de CREAME y 15 de Barcelona Activa que incluye directivos, empleados e incubados y que tuvieron una intervención relevante en los procesos de transformación de las dos organizaciones, complementándose con la observación y el análisis de documentos, que permitió conocer las visiones de los actores del cambio en CREAME y Barcelona Activa, de manera individual, transeccional y longitudinal. Las políticas y programas se institucionalizaron en procesos coercitivos, miméticos y normativos en los niveles directivos y en algunos empleados, asesores y consultores empresariales, sin reinstitucionalizarse en todas las funciones sustantivas de las incubadoras. Los principales aportes son la contrucción y empleo del marco analítico multidisciplinario, el desarrollo y aplicación del modelo interpretativo: pentágono multidisciplinario del cambio, el diseño y aplicación del Método Tridimensional de Análisis Cualitativo del Cambio Institucional y Organizacional (METACIO), la adaptación y aplicación creativa de la metodología de investigación cualitativa y los estudios de caso comparados, y la exposición de los impactos sociales, políticos y económicos que genera el cambio de las dos incubadoras.Ítem Analyses of the Morphometric Variation within Caiman crocodilus Species Complex in Colombia(Universidad EAFIT, 2022) Angulo-Bedoya, Mónica; Webster, Mark; Benítez, Hugo A.; Balaguera-Reina, Sergio; Correa, Santiago; Roberto, Igor J.; Moncada-Jimenez, Juan F.; Mazzotti, Frank J.; Espinoza-Donoso, Sebastian; Lemic, Darija; Correa Vélez, Santiago Alberto; Pinel Peláez, NicolásÍtem Analysis of the environmental licensing procedure for coastal environments in Colombia : a geomorphological perspective from the concept of susceptibility to the effect of human interventions(Universidad EAFIT, 2019) Pereira Pomárico, Cristina Isabel; Correa Arango, Iván DaríoImportant flaws in the environmental licensing procedures in Colombia are directly related to the generalized degradation of its coastal fringes and littoral zones. These areas are severely affected by human interventions that interfere with natural processes and severely modify their sedimentary balances, geomorphological contexts, and physical-biotic conditions. Among many other examples, the following stand out: a) the widespread erosion and destruction of beaches and dunes in the Magdalena River delta, associated with the construction of the Bocas de Ceniza jetties; b) the drastic modification of the hydrodynamics of the littorals at the Atlantic and Magdalena departments due to linear infrastructure projects; c) the hyper-salinization and loss of more than 30,000 hectares of mangrove in the lagoon complex of the Ciénaga Grande de Santa Marta (CGSM) due to the expansion of the agricultural frontier and linear infrastructure projects; d) the accelerated retreat of beaches and cliffs in the southern Caribbean, due to activities such as deforestation, beach material extraction, and disordered and chaotic construction of nearly 500 rigid shore protection works; and e) the salinization of more than 10,000 hectares of freshwater marshes in the Bay of Cispatá as a consequence of the induced formation of the new delta of Tinajones. In this sense, the location of infrastructure in geological and geomorphologically unstable lands, affected by phenomena such as coastal subsidence and mud diapirism, poses first order natural threats and risks. This is a palpable panorama in the present and future of urban and rural areas of cities such as Barranquilla, Cartagena, Arboletes and Necoclí, all of them with future developments (industry, ports, urban development) of the greatest importance. The environmental costs associated with such interventions are incalculable, not counting the existence of numerous other examples, which demonstrate among other factors an insufficient acknowledgment to geomorphology in the evaluation, monitoring, and control of human interventions in the marine-coastal environment. These environmental management functions in Colombia are provided through the environmental licensing procedure, which rests upon national and regional authorities according to Law 99 of 1993. In the above context, the following research questions arise: What elements of the environmental licensing of interventions in coastal environments can be improved, giving priority to the particular geomorphological contexts of the intervention zones? How has the regulatory system evolved in Colombia with respect to human interventions on coastal environments? What technical improvements can be made to the Colombian regulatory framework to guide the evaluation, monitoring, and control of human interventions from the geomorphological approach of susceptibility? This research work examines the environmental regulatory framework that currently governs Colombian coastal zones, through two geographic levels. At the first macro level, human interventions 16 are characterized and analyzed on the continental Caribbean coast, a region that represents a significant sample of the Colombian context due to its higher levels of human occupation and consequent anthropogenic disturbances. At a second level, in greater detail, the conceptual and methodological approach resulting from this research is defined and illustrated, with the demonstration in one of the coastal environmental units defined by decree 1120 of 2013 for integrated coastal management. To answer the questions raised, Chapter I briefly introduces the historical geomorphological evolution of the Colombian coastlines since the end of the XVIII century. The complex geology and geomorphology of the Caribbean and Pacific coasts of Colombia are evident in this "appetizer", in which low-relief deltaic islands and mangroves contrast with steep rocky reliefs, cliffs and wide emerged and submerged coastal platforms. The historical evolution of the Colombian littorals involves changes in the coastline estimated in hundreds of meters, at maximum rates of 40 meters a year (Punta Rey, Arboletes, Tumaco Bay), and land losses and gains of the order of tens of square kilometers (Ciénaga de Mallorquín, Isla Cascajo, Tinajorenas Delta - Cispatá, Bay, Urabá Gulf, San Juan and Patía river deltas). These cases reflect drastic variations in the sediment balances of the coast, many of them caused or heavily influenced by human actions, such as navigation infrastructure, modification of river courses and coastal protection works. Chapter II identifies the geomorphological perspective in the environmental licensing of coastal interventions in Colombia, based on its comparison with the regulatory frameworks of Italy, Spain, and Cuba. The interviews and documentary reviews highlighted 59 interventions associated with human uses and activities in the coastal zones, whose compulsory nature for the licensing varies among countries. The natural geomorphological processes were also analyzed within the technical criteria included in the official guidelines for environmental studies. It is concluded that, despite the worldwide acceptance of environmental impact assessments through a licensing procedure, their application in coastal environments is still very diverse and limited in terms of the pertinence of the geomorphological processes that configures the coast. Therefore, seven good practices for the evaluation and control of anthropogenic impacts in the coastal zone are underlined, and a new process-oriented approach is introduced for environmental licensing procedures. In Chapter III, an inventory and characterization of human interventions on the continental coast of the Colombian Caribbean are documented, to establish a regional baseline. Based on images from Google Earth, a total of 2,742 works and activities were located, representing 29 different types of human interventions. This inventory was complemented with an evaluation of the general impact of each intervention, based on four attributes of its geomorphological effects, namely, extension, intensity, reversibility, and persistence. The three most common types of human interventions (low-density settlements, groins and luxury settlements with dock) were also the ones with the higher environmental impact. However, some interventions (e.g., high-density settlements or road infrastructure) had higher environmental impact values than more frequent ones. 17 Based on this exhaustive analysis of the Colombian Caribbean, Chapter IV evaluates the national environmental regulatory framework applicable to coastal areas. It evidences that the licensing procedure in Colombia currently regulates only four of the ten types of interventions with greater effect in the Colombian coastal zones. Also, the number of works and activities covered in each new legislative reform consistently decreased over time. In addition, three policy implications were extracted for coastal and ocean planning, related to a) the geographic diversity of tropical coastal zones; b) the need for territorial carrying capacity instruments and; c) the lack of articulation of territorial planning instruments. The conclusions identify an important gap between technical and political decision making in the environmental regulatory framework of Colombia, which stresses the need for the design of novel methods to assess the breadth and length of geomorphological dynamics in an environmental management context. Therefore, the previous chapters highlight three important deficiencies in Colombia, with respect to the environmental management of human interventions in coastal areas: 1) the absence of a strategy to determine interventions that require an environmental licensing procedure (screening); 2) a poor definition of the scope of environmental studies through relevant information requirements (scoping) and; 3) the disarticulation of environmental management instruments, such as territorial planning and environmental licenses. All these elements ratify that the environmental regulatory framework in Colombia has been insufficient to date to manage the anthropogenic impact in coastal environments due to the unawareness of the natural susceptibility to the effect of human interventions. In this work, the susceptibility is defined as the predisposition of an environmental unit (socio-natural system) to experience changes or affectation due to the introduction of human interventions. In order to propose improvements to the Colombian environmental system, Chapter V establishes a new conceptual and methodological approach to guide the evaluation, monitoring, and control of human impacts from a geomorphological perspective. This novel product has been called Susceptibility to Human Interventions for Environmental Licensing Purposes (SHIELP). The architecture of this model has three components, which are particular to a kind of environment, namely, geomorphological processes, geomorphological configurations and potentially impacting human interventions. Each of these components is translated into a variable by means of expert qualifications along with a fuzzy logic computation strategy. Therefore, the expert-diffuse system SHIELP qualifies the susceptibility of a distinctive landform to the effects of a characteristic type of human intervention, through the estimated perturbation in each geomorphological process that configures the kind of environment under study. As a demonstration, this chapter also documents the design of the expert-diffuse system for coastal environments, drafted from research workshops with members of the marine and coastal research institute INVEMAR (In Spanish: Instituto de Investigaciones Marinas y Costeras “José Benito Vives de Andréis”). The role of this institute as an official adviser to the environmental authorities in matters of impact assessment demonstrates its relevance to support the expert-knowledge base of the model. 18 As a consequence, the SHIELP model was applied with the parameters established for coastal environments, resulting in a database of susceptibility values for 4,524 interactions (littoral configuration vs intervention). The real applicability of this exercise corresponds to the translation of this database into a technical criterion to improve the Colombian regulatory framework. On the one hand, five susceptibility ranges were linked to five differentiated instruments, two of which articulate environmental licensing with territorial plans, while the others differentiate the pertinent degree of licensing for human interventions according to location properties (screening). On the other hand, the differentiated instruments were also combined with four degrees of information requirements for the definition of the scope in the respective environmental studies (scoping). In this way, the susceptibility value of a given intervention in a given configuration (interaction) would fit a percentile range that places its environmental control in a territorial competence (regional or national), and through a specific licensing instrument, with differentiated information requirements for the baseline definition. Finally, the operation of the SHIELP model was also demonstrated with a case study: the environmental coastal unit Magdalena River - Canal del Dique complex - Ciénaga Grande de Santa Marta lagoon system. The geographic information of this regional coastal unit was interpreted according to the parameters defined in the SHIELP model for coastal environments. 154 polygons were delimited in the study area, according to the 40 coastal configurations identified. As a result, 13 cartographic maps represent this area, with the levels of susceptibility attributed to each configuration for the 52 potentially impacting interventions. In order to illustrate the applicability of the model, four scenarios are presented to discriminate interventions by environmental management instrument (screening) and to define information requirements on geomorphological processes (scoping). In this way, the SHIELP model specifies the environmental licensing instrument for human interventions and the corresponding scope of the technical study, given the characteristics of its interaction with the geomorphological configuration. The Overall Conclusions document reflections and recommendations to the Colombian national environmental system – SINA (in Spanish: Sistema Nacional Ambiental) to implement the results of this research. In addition, this work opens a broad perspective for future research in the approach of susceptibility to the effect of human interventions. The SHIELP model for coastal environments can be replicated in different geographies to progressively articulate a national database of coastal susceptibility. Also, the presented methodological scheme can be applied in different kinds of environments, other than the coastal zone. The extension of this approach of geomorphological susceptibility to the variety of tropical ecosystems would set the path for a successful transition from the current anthropocentric and fragmentation-oriented conception towards an ecosystem-based management approach.Ítem Los aportes de la teoría crítica a la construcción de un concepto complementario de responsabilidad social : contrastación en prácticas empresariales de Barranquilla(Universidad EAFIT, 2011) Mejía Reátiga, Camilo; Toro Jaramillo, Iván DaríoThis doctoral research presents the results related to the contributions of critical theory to the construction of the concept of Social Responsibility, contrasting business practices in Barranquilla. This thesis has collected in detail the state of the art about the research problem, Social Responsibility, and developed the key assumptions of Critical Theory (CT) as a basis for a complementary foundation for Social Responsibility (SR). The research results were incorporated into field work (which includes four phases that are described in the research methodology chapter) through tables, graphs, frequency and comparative analysis of the collected data, the empirical evidence of the business practices of large firms in the city of Barranquilla. Finally, this thesis presents a proposal for a complementary foundation of social responsibility, contrasted with the business practice, from a conceptualized vision and elements derived from Critical Theory. Likewise, included spaces left open for future research, from the development of this doctoral research.Ítem Bacillus sp. strains and their inducible in vitro antagonism : a biochemical and molecular study(Universidad EAFIT, 2018) Sierra Zapata, Laura; Villegas Escobar, Valeska; Romero Tabarez, MagallyDiscovering novel antibiotic substances from natural sources and revitalizing the pipeline for screenings of naturally sourced substances that could render new bioactive compounds, is a priority nowadays in the face of a world crisis of antimicrobial resistance. This research was focused on disclosing an observed antagonism system composed of Bacillus sp. strains producing inducible antimicrobial activity against the plant pathogen Ralstonia solanacearum, a widespread bacterium that causes bacterial wilt disease to a great variety of plant species, including many agriculturally important ones as are bananas. The inducible phenomenon was discovered during the screening of 1493 aerobic endospore forming bacteria against plant pathogens. It was observed that in the presence of the chemical compound Triphenyl Tetrazolium Chloride (TTC), which belongs to the group of synthetic compounds known as tetrazolium salts used to monitor cell respiration, Bacillus sp. strains produced inhibition zones against the bacterial plant pathogen and other pathogenic bacterial species, while in the absence of the compound they did not have any bioactivity. During biochemical characterization, it was evidenced that although the phenomenon was observable across several species of the order Bacillales, strains belonging to B. cereus, B. pumilus and B. subtilis were outstanding in their inducible antagonism potential, among other species tested. Besides, relevant traits revealed that other tetrazolium salts did not induce antagonistic activity and that the addition of antioxidant compounds did not reduce the inducible antagonistic activity. Also, R. solanacearum sensitivity to antibiotics was not increased by the addition of TTC and the inducible activity was independent of the presence of the pathogenic strain. In order to determine genes and pathways that were activated under TTC conditions, transcriptomic and metabolomics analysis were performed. Transcriptomic results revealed that specific pathways of the nitrogen metabolism, such as pyrimidines, purines and histidine biosynthetic routes, were 2 to 5 fold up-regulated in B. subtilis NCIB-3610 cells growing under TTC presence. On the other hand, metabolomic analysis showed that 28 specific compounds were either unique or 3 to 5 fold more abundant in active extracts obtained from inducible conditions, compared to non-induced controls. Data mining on public chemical databases, using intrinsic properties of the selected compounds, suggests that they mostly belong to chemical families of carbamates, imidazoles, pyrrolidines, pyrimidines, dipeptides and oligopeptides, all of which are part of the nitrogen metabolism. Results suggest that Bacillus cells reduction of TTC into triphenyl formazan (TPF) and its further accumulation inside the cells, induces the production of nitrogen-derived compounds, either by activation of nitrogen metabolism biosynthetic pathways or by a biotransformation of TPF into derivatives. Once produced, the compounds are secreted into the medium and act as antimicrobials against other bacteria.Ítem Caracterización del flujo hidrodinámico y evaluación de su impacto en la acumulación y producción de hidrocarburos en el sector sur de la Cuenca de Llanos, Colombia(Universidad EAFIT, 2022) Gómez Moncada, Ricardo Andrés; Jaramillo Uribe, Marcela; Mora Bohorquez, AndrésThe southern sector of the Llanos Basin in Colombia has been identified as a basin where the hydrodynamic flow has influenced the potential of hydrocarbon storage and production. In this area the hydrodynamic flow coincides with a province of heavy and extra-heavy crude oils, which has hypothesized for this area, a critical condition that decreases the potential for hydrocarbon retention by the effect of hydrodynamic flow and the geochemical nature of the fluids. This work provides a comprehensive view to describe the impact of regional hydrodynamic flow on retention of the heavy oil accumulations present in the reservoirs that are part of the most important regional flow unit identified in the Southern Llanos Basin. The Basal Flow Unit (BFU) constitutes a basin-scale flow unit that hydraulically and laterally connects rocks from the Cretaceous (west) to the Oligocene (east) and extends from the basin's southwestern margin up to hundreds of kilometers within the Llanos foreland basin, and whose main water recharge zone has been identified towards the eastern flank of the Serranía de la Macarena. To understand the impact of the physicochemical properties of the fluids, we analyze the relationship between hydraulic data and the main characteristics of the fluids present in the BFU, and their spatial distribution on the present-day configuration of this flow unit. This analysis integrated information from hydraulic heads, SARA analysis (Saturates, Aromatics, Resins, and Asphaltenes), Whole Oil Gas Chromatography analysis, API-gravity, and oil densities. In addition, hydrochemical analysis of the primary ions and isotopic analysis (δ18O and δD) was performed in groundwater samples from the BFU, which was integrated with deep resistivity data measured in producing and exploratory oil wells in the area. The new isotopic analyzes of this study (δ18O and δD), and data from previous studies, allowed establishing the Local Meteoric Water Line (LMWL) for the Llanos basin. The δ18O and δD values of the groundwater samples follow the Local Meteoric Water Line proposed for the Llanos basin, supporting the presence of meteoric waters in the Basal Flow Unit and whose influence it extends from the recharge zone to more than 300 km east of the basin. The results allowed identifying the southwestern corner of the southern Llanos Basin as the area with the highest hydrodynamic flow impact, and therefore, the area with the least potential for hydrocarbon retention, attributing as the main causes: 1) the proximity to recharge areas, and 2) the low contrast of fluids densities (freshwaters and highly biodegraded heavy crude oils), implying high Tilt Amplification Factor (TAF) values. Furthermore, gradual changes in resistivities and ions concentration in groundwaters suggest the eastern flank of the Serranía de la Macarena as the main recharge zone of meteoric waters into the BFU. Finally, numerical simulation techniques were used to analyze the behavior of hydrocarbon drainage under hydrodynamic conditions, obtaining a first approximation to the average linear groundwater flow velocities between 10-3 and 10-4 ft/day.Ítem Cómo emergen las nuevas formas de organizarse en la empresa multinegocio : una aproximación desde la estrategia como práctica(Universidad EAFIT, 2023) Rozo Villegas, Alejandro; Vélez Castiblanco, Jorge IvánÍtem Compendium of publications on: differential operators on manifolds for CAD CAM CAE and computer graphics(Universidad EAFIT, 2020) Mejía Parra, Daniel; Ruiz Salguero, Oscar Eduardo; Posada Velásquez, Jorge LeónThis Doctoral Thesis develops novel articulations of Differential Operators on Manifolds for applications on Computer Aided Design, Manufacture and Computer Graphics, as follows: (1) Mesh Parameterization and Segmentation. Development and application of Laplace-Beltrami, Hessian, Geodesic and Curvature operators for topology and geometry – driven segmentations and parameterizations of 2-manifold triangular meshes. Applications in Reverse Engineering, Manufacturing and Medicine. (2) Computing of Laser-driven Temperature Maps in thin plates. Spectral domain - based analytic solutions of the transient, non-homogeneous heat equation for simulation of temperature maps in multi-laser heated thin plates, modeled as 2-manifolds plus thickness. (3) Real-time estimation of dimensional compliance of hot out-of-forge workpieces. A Special Orthogonal SO(3) transformation between 2-manifolds is found, which enables a distance operator between 2-manifolds in R^3 (or m-manifolds in R^n). This process instruments the real-time assessment of dimensional compliance of hot workpieces, in the factory floor shop. (4) Slicing or Level-Set computation for 2-manifold triangular meshes in Additive Manufacturing. Development of a classification of non-degenerate (i.e. non-singular Hessian) and degenerate (i.e. singular Hessian) critical points of non-Morse functions on 2-manifold objects, followed by computation of level sets for Additive Manufacturing. Most of the aforementioned contributions have been screened and accepted by the international scientific community (and published). Non-published material corresponds to confidential developments which are commercially exploited by the sponsors and therefore banned from dissemination.Ítem Compendium on "assessment of intended deformations and kinematic identification of parallel mechanisms under quasi-static condictions"(Universidad EAFIT, 2010) Durango Idárraga, Sebastián; Ruíz Salguero, Óscar EduardoÍtem El complejo sistema de acoplamientos y contradicciones en una organización semiautónoma : un análisis desde la perspectiva de los sistemas débilmente acoplados(Universidad EAFIT, 2023) Arango Vásquez, Leonel; Gentilin, MarianoIn the field of organizational studies, it is possible to approach organizational phenomena through a conceptual framework known as Loosely Coupled Systems (hereinafter referred to as SDA). This perspective characterizes organizations in three main ways. Firstly, organizations are composed of distinct organizational units with unique features (Orton and Weick, 1988). Secondly, there are both tight and loose couplings between these organizational units (Heldal, 2010). Lastly, there exist coupling mechanisms that affect both the organizational units and their members (Beekun and Glick, 2001a). The SDA perspective also recognizes the coexistence of contradictions within organizations, which are seen as inherent aspects rather than undesirable elements (Weick, 1976; Orton and Weick, 1990). When examining the distinctive features, tight and loose couplings, and coupling mechanisms, the central concepts of SDAs, it is noteworthy that many analyses focus on only one of these aspects. Some studies concentrate solely on distinctive features, couplings, or coupling mechanisms. In certain cases, the analysis is further limited to either tight or loose couplings, or it explores only one specific type of coupling mechanism, such as regulatory, cultural, or structural. This narrow focus restricts the comprehensive understanding of organizational couplings. To overcome this limitation, this doctoral thesis recognizes the SDA perspective as a means to comprehend organizations holistically and in depth, thereby making the intelligible elements evident and the unintelligible elements more visible and observable. Consequently, this research employs an integrated approach to analyze the three central concepts of SDA and their relationship with organizational contradictions. It acknowledges that organizations are not monolithic and stable entities but rather complex systems that warrant examination from various angles. Based on this premise, the thesis proposes a more comprehensive form of organizational analysis, simultaneously considering the distinctive features, tight and loose couplings, and coupling mechanisms. Through this approach, the unique characteristics of an organization's complex system of couplings and contradictions, particularly within a semi-autonomous context, can be illuminated.Ítem Computational Geometry Contributions Applied to Additive Manufacturing(Universidad EAFIT, 2022) Montoya Zapata, Diego Alejandro; Ruiz Salguero, Oscar Eduardo; Posada Velásquez, Jorge León