80 research outputs found

    Implicaciones de la inversión en recursos intangibles sobre la capacidad exportadora de las empresas de Santander, Colombia.

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    Este artículo analiza la incidencia de la inversión en recursos intangibles sobre la capacidad exportadora de las empresas de Santander; para ello, se estima su correlación mediante dos modelos de regresión lineal uniecuacional: uno sin corrección de sesgo y otro aplicando la corrección de sesgo propuesta por Heckman (1979). Los resultados muestran que existe una relación directa entre la inversión en patentes, know how, crédito mercantil, licencias, marcas, concesiones, franquicias y derechos, y la capacidad de penetración en el mercado exterior. Sin embargo, los tipos de recursos inmateriales en los que se realizan mayores inversiones son aquellos que tienen menor incidencia en la capacidad exportadora.This article analyzes the impact of investments in intangible resources on the exporting capacity of companies in Santander; to this effect, their correlation is estimated using two uniequational linear regression models: one without bias correction and the other one applying the bias correction proposed by Heckman (1979). The results show that there is a direct relationship between investments in patents, know-how, merchant credit, licenses, brands, concessions, franchises and rights, and the ability to expand to foreign markets. Nevertheless, the types of intangible resources that receive the largest investments are those that have the least impact on export capacity

    Biocorrosion on water injection systems of the oil and gas industry: New experimental models from the field

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    The oil and gas industry is impacted by important economic losses due to corrosion problem. As part of this problem, microbially influenced corrosion (MIC) is still a subject of research. The most often evoked and well acknowledge MIC mechanism is linked to sulphate reducing bacteria (SRB). However, some studies have shown that MIC can occur even when SRB is not present in the corroding environment; in this framework, the main objective of the thesis is to provide new insights on corrosion of carbon steel caused by other mechanisms different to those described with SRB. First, the influence of an electroactive strain, G. sulfurreducens (an iron reducing bacteria, IRB) on the corrosion/protection of steel C1145 was studied. When phosphate species are present in the medium, bacteria promote the formation of an iron phosphate layer (vivianite) that afterwards protects the material. In presence of NH4+, corrosion rates are higher but bacteria decrease the dissolution of the material. In the second part, field samples from pigging operations performed in water injection pipelines were analysed from microbiological and electrochemical corrosion points of view. Molecular analysis and identification of the biofilm community show the presence of sulfidogenic species besides SRB. These bacteria can stimulate metal corrosion through production of organic acids, CO2 and different sulphur species such as H2S. Moreover, it was proved that the consortium contained in field samples accelerated corrosion of carbon steel mainly by production of sulphide species

    Geobacter sulfurreducens: an iron reducing bacterium that can protect carbon steel against corrosion ?

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    The effect of Geobacter sulfurreducens on the electrochemical behaviour of carbon steel in anaerobic phosphate solution is studied here. In natural environments, G. sulfurreducens is able to reduce Fe(III) to Fe(II) during the oxidation of acetate. High availability of Fe(II) promoted the formation of an iron (II) phosphate layer on the steel. It is assumed that this phosphate layer, formed only when bacteria were present, is responsible for maintaining the corrosion potential stable even after intrusion of air. In contrast, the corrosion potential in the abiotic experiments suffered an increase of 450 mV after few hours of exposure to air

    FORMULACIÓN DE AGENDAS DE CIENCIA Y TECNOLOGÍA PARA LAS PROVINCIAS DE GUANENTÁ Y COMUNERA EN EL DEPARTAMENTO DE SANTANDER COLOMBIA

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    RESUMENLa experiencia desarrollada de formulación de agendas de ciencia y tecnología en dos de las provincias del Departamento de Santander Colombia, contó con la participación de representantes de los entes territoriales, el sector científico y tecnológico, el sector productivo y las organizaciones sociales con presencia en la región. Esta investigación adelantada directamente en comunidades provinciales, ha permitido un nivel más detallado del proceso de regionalización de la ciencia, la tecnología y la innovación en Colombia. El desarrollo del proyecto se realizó en tres grandes momentos: Momento Uno: correspondió a aquellas actividades de preparación, documentación, diseño metodológico y análisis que permitieron conocer más a fondo la dinámica funcional de las provincias así como determinar el diseño metodológico de los talleres de la agenda. Momento Dos: se proporcionó a los actores provinciales los conceptos, instrumentos y herramientas necesarias para conocer y participar en la construcción de la Agenda y constituirse posteriormente en los agentes dinamizadores de losproyectos, procesos y actividades derivados de ella. En cada provincia se realizaron: un conversatorio y tres talleres. Momento tres: Se hizo la organización de la información, elaboración de documentos y socialización de resultados. Dentro de los principales ítems consolidados en el documento de Agendas estuvieron: Definición de subsistemas provinciales, factores críticos de la Provincia y capacidades científico tecnológicas. También se hizo el planteamiento prospectivo de la agenda que incluyó estrategias, líneas estratégicas de acción, programas y proyectos, indicadores, mecanismos de verificación y fechas máximas de cumplimiento así como estrategias de ejecución de cada agenda. La realización de este proyecto en dos de las provincias de Santander, ha permitido a las comunidades sentirse verdaderamente representadas y con poder de decisión en el desarrollo y planeación de sus localidades.PALABRAS CLAVE: Regionalización, Ciencia, Tecnología, Agenda.  ABSTRACTThe developed experience in formulation of science and technology agendas in two provinces at Santander's department had the participation of territorial entities, the scientific, technology and productive sectors and the social organizations in the region. This investigation forwarded directly to provincial communities, has allowed a better detailed level of the process in order to regionalize the science, technology, and the innovation in the country, Colombia. The development project was realized over three important moments: Moment one: Were developed some activities like preparation, documentation, methodical design and any analysis to get to know the functional dynamic of the provinces and to determine the design methods in the agenda's workshop. Moment two: the concepts and the necessary instruments were given to provincial actors in order to know and participate in building the agenda. and to be the dynamic elements in projects, processes and activities derived from the agenda.. In each province was realized a meeting and three workshops Moment three: Information was organized and a socialization of results was made. The main aspects that were treated in the agenda were: provincials sub-systems definitions, extreme factors of the province, and scientific-technologic capabilities. It was made an agenda prospective debate with strategies, action ways, programs and projects, indicators and verification mechanisms as dates to fulfill the agendas execution. Implementing this project in two provinces in Santander has given to the communities the feeling of being represented and with decision power in programs made in their communities.KEYWORDS: Regionalization, Science, Technology, Calendar

    FORMULACIÓN DE AGENDAS DE CIENCIA Y TECNOLOGÍA PARA LAS PROVINCIAS DE GUANENTÁ Y COMUNERA EN EL DEPARTAMENTO DE SANTANDER COLOMBIA

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    RESUMENLa experiencia desarrollada de formulación de agendas de ciencia y tecnología en dos de las provincias del Departamento de Santander Colombia, contó con la participación de representantes de los entes territoriales, el sector científico y tecnológico, el sector productivo y las organizaciones sociales con presencia en la región. Esta investigación adelantada directamente en comunidades provinciales, ha permitido un nivel más detallado del proceso de regionalización de la ciencia, la tecnología y la innovación en Colombia. El desarrollo del proyecto se realizó en tres grandes momentos: Momento Uno: correspondió a aquellas actividades de preparación, documentación, diseño metodológico y análisis que permitieron conocer más a fondo la dinámica funcional de las provincias así como determinar el diseño metodológico de los talleres de la agenda. Momento Dos: se proporcionó a los actores provinciales los conceptos, instrumentos y herramientas necesarias para conocer y participar en la construcción de la Agenda y constituirse posteriormente en los agentes dinamizadores de losproyectos, procesos y actividades derivados de ella. En cada provincia se realizaron: un conversatorio y tres talleres. Momento tres: Se hizo la organización de la información, elaboración de documentos y socialización de resultados. Dentro de los principales ítems consolidados en el documento de Agendas estuvieron: Definición de subsistemas provinciales, factores críticos de la Provincia y capacidades científico tecnológicas. También se hizo el planteamiento prospectivo de la agenda que incluyó estrategias, líneas estratégicas de acción, programas y proyectos, indicadores, mecanismos de verificación y fechas máximas de cumplimiento así como estrategias de ejecución de cada agenda. La realización de este proyecto en dos de las provincias de Santander, ha permitido a las comunidades sentirse verdaderamente representadas y con poder de decisión en el desarrollo y planeación de sus localidades.PALABRAS CLAVE: Regionalización, Ciencia, Tecnología, Agenda.  ABSTRACTThe developed experience in formulation of science and technology agendas in two provinces at Santander's department had the participation of territorial entities, the scientific, technology and productive sectors and the social organizations in the region. This investigation forwarded directly to provincial communities, has allowed a better detailed level of the process in order to regionalize the science, technology, and the innovation in the country, Colombia. The development project was realized over three important moments: Moment one: Were developed some activities like preparation, documentation, methodical design and any analysis to get to know the functional dynamic of the provinces and to determine the design methods in the agenda's workshop. Moment two: the concepts and the necessary instruments were given to provincial actors in order to know and participate in building the agenda. and to be the dynamic elements in projects, processes and activities derived from the agenda.. In each province was realized a meeting and three workshops Moment three: Information was organized and a socialization of results was made. The main aspects that were treated in the agenda were: provincials sub-systems definitions, extreme factors of the province, and scientific-technologic capabilities. It was made an agenda prospective debate with strategies, action ways, programs and projects, indicators and verification mechanisms as dates to fulfill the agendas execution. Implementing this project in two provinces in Santander has given to the communities the feeling of being represented and with decision power in programs made in their communities.KEYWORDS: Regionalization, Science, Technology, Calendar

    The adaptive potential of the M-domain of yeast Hsp90 [preprint]

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    Comparing the distribution of fitness effects (DFE) of new mutations across different environments quantifies the potential for adaptation in a given environment and its cost in other environments. So far, results regarding the cost of adaptation across environments have been mixed, and there were no sufficiently large data sets to map its variation along the genome. Here, we study the DFEs of ≈2500 amino-acid changing mutations obtained from deep mutational scanning of the 118 amino-acid-long middle domain of the heat-shock protein Hsp90 in five environments and at two expression levels. This region is known to be important for client binding, stabilization of the Hsp90 dimer, stabilization of the N-M and M-C interdomains and regulation of ATPase-chaperone activity. Despite the diverse and stressful environments, we find that fitness correlates well across environments, with the exception of one environment, diamide. Consistent with these results, we find very little cost of adaptation; on average only one in seven beneficial mutations is deleterious in another environment. We identify a hotspot of beneficial mutations in a region of the protein that is located within an allosteric center. The identified protein regions that are enriched in beneficial, deleterious, and costly mutations coincide with residues that are involved in the stabilization of Hsp90 interdomains and stabilization of client binding interfaces or residues that are involved in ATPase chaperone activity of Hsp90. Thus, our study yields information regarding the role and adaptive potential of a protein sequence that complements and extends known structural information

    The Adaptive Potential of the Middle Domain of Yeast Hsp90

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    The distribution of fitness effects (DFEs) of new mutations across different environments quantifies the potential for adaptation in a given environment and its cost in others. So far, results regarding the cost of adaptation across environments have been mixed, and most studies have sampled random mutations across different genes. Here, we quantify systematically how costs of adaptation vary along a large stretch of protein sequence by studying the distribution of fitness effects of the same approximately 2,300 amino-acid changing mutations obtained from deep mutational scanning of 119 amino acids in the middle domain of the heat shock protein Hsp90 in five environments. This region is known to be important for client binding, stabilization of the Hsp90 dimer, stabilization of the N-terminal-Middle and Middle-C-terminal interdomains, and regulation of ATPase-chaperone activity. Interestingly, we find that fitness correlates well across diverse stressful environments, with the exception of one environment, diamide. Consistent with this result, we find little cost of adaptation; on average only one in seven beneficial mutations is deleterious in another environment. We identify a hotspot of beneficial mutations in a region of the protein that is located within an allosteric center. The identified protein regions that are enriched in beneficial, deleterious, and costly mutations coincide with residues that are involved in the stabilization of Hsp90 interdomains and stabilization of client-binding interfaces, or residues that are involved in ATPase-chaperone activity of Hsp90. Thus, our study yields information regarding the role and adaptive potential of a protein sequence that complements and extends known structural information

    Investigating the influence of environment on the evolution of Hsp90 using comprehensive fitness maps [preprint]

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    Gene-environment interactions have long been theorized to influence molecular evolution. However, the environmental dependence of most mutations remains unknown. Using deep mutational scanning, we engineered budding yeast with all 44,604 single codon changes encoding 14,160 amino acid variants in Hsp90 and quantified growth effects under standard laboratory conditions and under five stress conditions (elevated temperature, nitrogen starvation, elevated salinity, high ethanol concentration, and oxidative stress caused by diamide). To our knowledge these are the largest comprehensive fitness maps of point mutant growth effects that have been determined. The growth effects of many variants differed between each of the conditions, indicating that environmental conditions can have a large impact on the evolution of Hsp90. Multiple variants provided growth advantages relative to wildtype Hsp90 under individual conditions, however these variants tended to exhibit growth defects in other environments. The diversity of Hsp90 sequences observed in extant eukaryotes preferentially contain amino acid variants that supported robust growth under all tested conditions. Thus, rather than favoring substitutions in individual conditions, the long-term selective pressure on Hsp90 may have been that of fluctuating environments, leading to robustness under a variety of conditions

    Corrosion of low carbon steel by microorganisms from the ‘pigging’ operation debris in water injection pipelines

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    Present in all environments, microorganisms develop biofilms adjacent to the metallic structures creating corrosion conditions which may cause production failures that are of great economic impact to the industry. The most common practice in the oil and gas industry to annihilate these biofilms is the mechanical cleaning known as “pigging”. In the present work, microorganisms from the “pigging” operation debris are tested biologically and electrochemically to analyse their effect on the corrosion of carbon steel. Results in the presence of bacteria display the formation of black corrosion products allegedly FeS and a sudden increase (more than 400 mV) of the corrosion potential of electrode immersed in artificial seawater or in field water (produced water mixed with aquifer seawater). Impedance tests provided information about the mechanisms of the interface carbon steel/bacteria depending on the medium used: mass transfer limitation in artificial seawater was observed whereas that in field water was only charge transfer phenomenon. Denaturing Gradient Gel Electrophoresis (DGGE) results proved that bacterial diversity decreased when cultivating the debris in the media used and suggested that the bacteria involved in the whole set of results are mainly sulphate reducing bacteria (SRB) and some other bacteria that make part of the taxonomic order Clostridiales

    Escisión meso-rectal total por vía trans anal (TaTME). Experiencia institucional

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    Introducción. La cirugía es la base del tratamiento curativo del cáncer de recto. La escisión meso-rectal total ha permitido mejorar los desenlaces oncológicos, disminuyendo las tasas de recurrencia locorregional e impactando en la supervivencia global. El empleo de esta técnica en los tumores de recto medio o distal es un reto quirúrgico, en el que la vía trans anal, permite superar las dificultades técnicas. Método. Se realizó un estudio observacional retrospectivo, recolectando la información de los pacientes con cáncer de recto medio y distal llevados a cirugía con esta técnica, en dos instituciones de cuarto nivel en Medellín, Colombia, entre enero de 2017 y marzo de 2022. Se analizaron sus características demográficas, la morbilidad perioperatoria y la pieza quirúrgica. Resultados. Se incluyeron 28 pacientes sometidos al procedimiento trans anal y laparoscópico de forma simultánea; al 57 % se les realizó una ileostomía de protección. Hubo complicaciones en el 60,7 % de los pacientes; ocurrieron cuatro casos de fuga anastomótica. No se presentó ninguna mortalidad perioperatoria. Conclusiones. La tasa de morbilidad perioperatoria es acorde con lo reportado en la literatura. Se resalta la importancia de la curva de aprendizaje quirúrgica y de incluir la calificación de la integridad meso-rectal dentro del informe patológico. Se requiere seguimiento a largo plazo para determinar el impacto en desenlaces oncológicos, calidad de vida y morbilidad
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