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Imagen de apoyo de  Evaluation of the mechanical properties and degree of conversion of 3D printed splint material = Evaluación de las propiedades mecánicas y grado de conversión de material de férula impreso 3D

Evaluation of the mechanical properties and degree of conversion of 3D printed splint material = Evaluación de las propiedades mecánicas y grado de conversión de material de férula impreso 3D

Por: Leila; Gibreel Perea Mosquera | Fecha: 2021

Abstract: Objective: To evaluate the effect of post-curing method, printing layer thickness, and water storage on the me chanical properties and degree of conversion of a light-curing methacrylate based resin material (IMPRIMO® LC Splint), used for the fabrication of 3D printed occlusal splints and surgical guides. Methods: 96 bar-shaped specimens were 3D printed (Asiga MAX), half of them with a layer thickness of 100 ? m (Group A), and half with 50 ? m (Group B). Each group was divided in three subgroups based on the post-curing method used: post-curing with light emitting diode (LED) and nitrogen gas; post-curing with only LED; and non- post-curing. Half of the specimens from each subgroup were water-stored for 30 days while the other half was dry-stored (n = 8). Flexural strength and flexural modulus were evaluated. Additional specimens were prepared and divided in the same way for surface hardness (n = 96), fracture toughness, and work of fracture (n = 96). Five specimens were selected from each subgroup for evaluating the degree of conversion (DC). Data were collected and statistically analyzed with 1-way, 2-way ANOVA, and Tukey post-hoc analysis (? = 0.05). Results: The 2-way ANOVA showed that the post-curing method and water storage significantly affected the investigated mechanical properties (P < 0.001). The 1-way ANOVA revealed a statistically significant difference among the tested groups on the investigated properties (P < 0.001). After water storage, the 100 ? m subgroup post-cured with only LED showed higher flexural strength (51 ± 9) than the 50 ? m and 100 ? m subgroups that were post-cured with LED in addition to nitrogen gas atmosphere (38 ± 5, 30 ± 3) (p < 0.05). The 50 ? m subgroup post-cured with only LED showed the highest significant flexural modulus values (1.7 ± 0.08) (p < 0.05). However, the 50 ? m subgroup post-cured with LED plus nitrogen showed significantly higher surface hardness values (p < 0.05) among the investigated groups. The non-post-cured subgroups showed the lowest values, which were significantly different from the other subgroups (p < 0.05). Conclusion: The post-curing method, water storage, and printing layer thickness play a role in the mechanical properties of the investigated 3D Printed occlusal splints material. The combination of heat and light within the post-curing unit can enhance the mechanical properties and degree of conversion of 3D printed occlusal splints. Flexural strength and surface hardness can increase when decreasing printing layer thickness. Resumen: Objetivo: Evaluar el efecto del método de poscurado, el espesor de la capa de impresión y el almacenamiento de agua en el tiempo. Propiedades mecánicas y grado de conversión de un material de resina fotopolimerizable a base de metacrilato (IMPRIMO® LC Splint), utilizado para la fabricación de férulas oclusales y guías quirúrgicas impresas en 3D. Métodos: Se imprimieron en 3D (Asiga MAX) 96 muestras en forma de barra, la mitad de ellas con un espesor de capa de 100 ? m. (Grupo A), y la mitad con 50 ? m (Grupo B). Cada grupo se dividió en tres subgrupos según el poscurado. método utilizado: postcurado con diodo emisor de luz (LED) y gas nitrógeno; postcurado solo con LED; y no- después de curado. La mitad de los especímenes de cada subgrupo se almacenaron en agua durante 30 días mientras que la otra mitad se almacenó en agua. almacenado en seco (n = 8). Se evaluaron la resistencia a la flexión y el módulo de flexión. Se prepararon muestras adicionales. y dividido de la misma manera para dureza de la superficie (n = 96), tenacidad a la fractura y trabajo de fractura (n = 96). Se seleccionaron cinco ejemplares de cada subgrupo para evaluar el grado de conversión (DC). Los datos fueron recopilados y analizados estadísticamente con ANOVA de 1 vía, 2 vías y análisis posthoc de Tukey (? = 0,05).
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Evaluation of the mechanical properties and degree of conversion of 3D printed splint material = Evaluación de las propiedades mecánicas y grado de conversión de material de férula impreso 3D

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Imagen de apoyo de  Olive grove intensification negatively affects wintering bird communities in central Spain

Olive grove intensification negatively affects wintering bird communities in central Spain

Por: Catalina; Acebes Pérez García | Fecha: 2023

Abstract: Agricultural intensification is a persistent and growing threat to biodiversity worldwide. Olive groves cover extensive areasin the Mediterranean basin and play a fundamental role as refuge and wintering quarters for many bird species, but the effectsof their current intensification on bird communities remain unclear. This study aims to evaluate the response of wintering birdsto the management of olive groves with different degrees of intensification (traditional, intensive and superintensive manage-ment) in central Spain. Based on two bird censuses conducted in 25 groves in early and late winter, we examined the influenceof habitat structure and composition at different spatial scales on species richness and abundance of the entire farmland birdcommunity, and of the dietbased functional groups. Total species richness tended to decrease with intensive olive grove management, probably due to reduced habitat heterogeneity, whereas total abundance did not, indicating the capacity of intensiveand super-intensive olive groves to sustain large numbers of wintering birds. The negative effect of intensification was particu-larly evident in frugivore species richness, while frugivore abundance was positively (but marginally) associated with olive fruitavailability. Granivorous species were positively associated with lower vegetation cover, but insectivorous species did notrespond to intensification gradients. Species richness and abundance (total and by diet-based functional groups) also decreasedfrom early to late winter, which may be due to the effect of olive harvest, but also to an extreme cold event. Overall, our find-ings show how olive grove intensification and the associated management practices result in significant changes in habitatstructure and composition at different spatial scales, thus affecting wintering bird communities.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Olive grove intensification negatively affects wintering bird communities in central Spain

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Imagen de apoyo de  Estudio Morfofuncional del miembro torácico de Myrmecophaga tridactyla (hormiguero gigante) de la Orinoquia colombiana

Estudio Morfofuncional del miembro torácico de Myrmecophaga tridactyla (hormiguero gigante) de la Orinoquia colombiana

Por: Catalina; Rodríguez Pulido Pérez García | Fecha: 2019

Resumen: Uno de los mamíferos más emblemáticos de la Orinoquia colombiana es el hormiguero gigante, Myrmecophaga tridactyla, más conocido como oso palmero. Presenta adaptaciones anatómicas y comportamentales relacionadas con su alimentación especializada. Una de esas adaptaciones es el miembro torácico. En Colombia no se ha estudiado la relación entre las características morfológicas del miembro torácico y su funcionalidad. Por lo tanto, el objetivo de este estudio fue caracterizar morfológica y funcionalmente el miembro torácico de ejemplares de M. tridactyla de la Orinoquia colombiana. Se encontró que el miembro torácico se caracteriza por presentar unos músculos bien desarrollados, con aumento de áreas de inserción. Por otra parte, los huesos presentan accidentes óseos, crestas y procesos que incrementan la efectividad de los movimientos musculares. Las proporciones óseas de los huesos ulna y húmero indicaron que el miembro puede ejercer movimientos rápidos, fuertes, y de tipo excavatorio. Se evidenció que durante el forrajeo, diferentes movimientos musculares actúan entre sí para ejecutar una poderosa flexión digital, retracción del miembro y rotación de la mano. En conclusión, el miembro torácico del hormiguero gigante se encuentra adaptado morfológicamente a diferentes tipos de hábitos locomotores. Además, las características morfológicas de sus elementos óseos explican su forma de caminar en nudillos y comportamiento. El conocimiento anatómico y funcional puede servir como herramienta para prácticas médicas y manejo de ejemplares en cautiverio. También para entender el impacto que pueden llegar a tener la transformación de ecosistemas, en la fisiología y uso de hábitat en esta especie amenazada.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Estudio Morfofuncional del miembro torácico de Myrmecophaga tridactyla (hormiguero gigante) de la Orinoquia colombiana

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Imagen de apoyo de  Closing the Gap Between Concrete Maturity Monitoring and Nonlinear Timedependent FEM Analysis through a Digital Twin. Case Study: Post-tensioned Concrete Slab of an Office Building, Barcelona, Spain

Closing the Gap Between Concrete Maturity Monitoring and Nonlinear Timedependent FEM Analysis through a Digital Twin. Case Study: Post-tensioned Concrete Slab of an Office Building, Barcelona, Spain

Por: Héctor José; Chacón Posada Cárcamo | Fecha: 2022

Abstract: This paper proposes a pipeline for the automation of data between two realms: i) simulation, in a fully nonlinear, and time-dependent structural analysis model and, ii) concrete maturity monitoring data from the construction site. The connection enables an information construct understood for its use within the Digital Twin of the building during construction phases. The pipeline requires a comprehensive coordination between stakeholders at both the site (Construction) and the structural control office, which is challenging. The pipeline consists of a) temperature sensors, b) a mobile app connected to the sensor via Bluetooth with basic instructions for datagatherers, c) integration and interoperability of BIM, and, d) an advanced Finite Element (FE) model. By measuring the concrete temperature during many days, realistic concrete mechanical properties are inferred and infused into the FE models using adequate calibration. Two applications for the improvement of construction activities are identified. Formwork striking and tendons stressing. The paper describes the testbed of all the connections, for the construction of an in-situ casted concrete building in Barcelona, Spain.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Closing the Gap Between Concrete Maturity Monitoring and Nonlinear Timedependent FEM Analysis through a Digital Twin. Case Study: Post-tensioned Concrete Slab of an Office Building, Barcelona, Spain

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Imagen de apoyo de  Anglicisms in Higher Education and their impact on Spanish Terms

Anglicisms in Higher Education and their impact on Spanish Terms

Por: Jorge Mario Porras Garzón | Fecha: 2022

Abstract: The use of written texts in English for oral and written communication in Spanish in higher education settings is not uncommon today. The impact that this has on the lexical level has not yet been evaluated in the specialized communicative context of Colombian university higher education. As we will see, in this context the use of terminological Anglicisms is surpassing the Spanish terms that already exist to refer to the same concepts.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Anglicisms in Higher Education and their impact on Spanish Terms

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Imagen de apoyo de  Local competition and enhanced defense: how Metarhizium brunneum inhibits Verticillium longisporum in oilseed rape plants

Local competition and enhanced defense: how Metarhizium brunneum inhibits Verticillium longisporum in oilseed rape plants

Por: Catalina; Vidal Posada Vergara | Fecha: 2023

Abstract: Metarhizium brunneum is a soil-borne fungal entomopathogen that can associate with plant roots. Previous studies have demonstrated that root colonization by beneficial fungi can directly affect soilborne pathogens through competition and antibiosis, and can activate a systemic response in plants, resulting in a primed state for a faster and/or stronger response to stressors. However, the mechanisms by which Metarhizium inoculation ameliorates symptoms caused by plant pathogens are not well known. This study evaluated the ability of M. brunneum to protect oilseed rape (Brassica napus L.) plants against the soil-borne pathogen Verticillium longisporum, and investigated whether the observed effects are a result of direct interaction and/or plant-mediated effects. In vitro and greenhouse experiments were conducted to measure fungal colonization of the rhizosphere and plant tissues, and targeted gene expression analysis was used to evaluate the plant response. The results show that M. brunneum delayed pathogen colonization of plant root tissues, resulting in decreased disease symptoms. Direct competition and antibiosis were found to be part of the mechanisms, as M. brunneum growth was stimulated by the pathogen and inhibited the in vitro growth of V. longisporum. Additionally, M. brunneum changed the plant response to the pathogen by locally activating key defence hormones in the salicylic acid (SA) and abscisic acid (ABA) pathways. Using a split-root setup, it was demonstrated that there is a plant-mediated effect, as improved plant growth and decreased disease symptoms were observed when M. brunneum was in the systemic compartment. Moreover, a stronger systemic induction of the gene PR1 suggested a priming effect, involving the SA pathway. Overall, this study sheds light on the mechanisms underlying the protective effects of M. brunneum against soil-borne pathogens in oilseed rape plants, highlighting the potential of this fungal entomopathogen as a biocontrol agent in sustainable agriculture Metarhizium brunneum es un hongo entomopatógeno del suelo que puede asociarse con las raíces de las plantas. Resumen: Estudios previos han demostrado que la colonización de raíces por hongos beneficiosos puede afectar a patógenos del suelo a través de la competencia, antibiosis, y activar respuesta sistémica en las plants. Sin embargo, los mecanismos por los cuales este hongo atenúa los síntomas causados por fitopatógenos no son bien conocidos. Este estudio evaluó la capacidad de M. brunneum para proteger las plantas de colza (Brassica napus L.) contra Verticillium longisporum, e investigó si los efectos observados son el resultado de una interacción directa y/o efectos mediados por la planta. Se realizaron experimentos in vitro y en invernadero para medir la colonización fúngica de la rizosfera y los tejidos de la planta, y se midió la expresión de genes específicos relacionados con la respuesta de la planta a patógenos. Los resultados muestran que M. brunneum retrasó la colonización del patógeno en las raíces de la planta, y disminuyo los síntomas de la enfermedad. La competencia directa y la antibiosis son parte de los mecanismos, ya que el crecimiento de M. brunneum fue estimulado por el patógeno e inhibió el crecimiento in vitro de V. longisporum. Además, M. brunneum cambió la respuesta de la planta hacia el patógeno al activar localmente genes de defensa mediadas por el ácido salicílico (SA) y del ácido abscísico. Mediante un experimento de raíces divididas, se demostró que existe un efecto mediado por la planta, ya que se observó un mejor crecimiento de la planta y una disminución de los síntomas de la enfermedad cuando M. brunneum estaba en el compartimento sistémico. Además, una mayor inducción sistémica del gen PR1 sugirió un efecto de ""priming"", mediado por SA.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Local competition and enhanced defense: how Metarhizium brunneum inhibits Verticillium longisporum in oilseed rape plants

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Imagen de apoyo de  Digital twinning during load tests of railway bridges-case study: the high-speed railway network, Extremadura, Spain

Digital twinning during load tests of railway bridges-case study: the high-speed railway network, Extremadura, Spain

Por: Rolando; Ramonell Chacón | Fecha: 2023

Abstract: This article presents a case study with various developments of digital twinning of a sample of load tests performed on several railways bridges. The case study is located in Extremadura, South Western Spain and its aim is the generation of a validated, multi-layered information construct in the form of a digital twin as the result of a load test. This result is conceived, not only to verify the assumptions of the design of the bridge but also, to optimize future maintenance plans of the network. This particular case study is framed within a vaster European effort on digitization of the construction sector. Research and Innovation Actions within this demo case are aimed at integrating routine requirements and procedures of load tests with cutting edge digital technologies for the generation of validated virtual replica of these physical bridges. The generated twins during these load tests behaviourally match the obtained response during loading and as such, represent an ideal model for future simulations and behavioural predictions. Different data-gathering techniques and numerical models are integrated within a Common Data Environment (CDE). All efforts related to measurement, simulation, 3D modelling, assessment and validation can be wrapped up systematically for further use during regular operation of the asset.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Digital twinning during load tests of railway bridges-case study: the high-speed railway network, Extremadura, Spain

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Imagen de apoyo de  A Cas3-base editing tool for targetable in vivo mutagenesis

A Cas3-base editing tool for targetable in vivo mutagenesis

Por: Anna; PrietoVivas Zimmermann | Fecha: 2023

Abstract: The generation of genetic diversity via mutagenesis is routinely used for protein engineering and pathway optimization. Current technologies for random mutagenesis often target either the whole genome or relatively narrow windows. To bridge this gap, we developed CoMuTER (Confined Mutagenesis using a Type I-E CRISPR-Cas system), a tool that allows inducible and targetable, in vivo mutagenesis of genomic loci of up to 55 kilobases. CoMuTER employs the targetable helicase Cas3, signature enzyme of the class 1 type I-E CRISPR-Cas system, fused to a cytidine deaminase to unwind and mutate large stretches of DNA at once, including complete metabolic pathways. The tool increases the number of mutations in the target region 350-fold compared to the rest of the genome, with an average of 0.3 mutations per kilobase. We demonstrate the suitability of CoMuTER for pathway optimization by doubling the production of lycopene in Saccharomyces cerevisiae after a single round of mutagenesis. Resumen: La generación de diversidad genética mediante mutagénesis es utilizada habitualmente para la ingeniería de proteínas y la optimización de vías metabólicas. Las tecnologías actuales para realizar mutagénesis aleatoria a menudo se dirigen a todo el genoma o a secuencias relativamente estrechas de ADN. Para cerrar esta brecha, desarrollamos CoMuTER (mutagénesis confinada utilizando un sistema CRISPR-Cas tipo I-E, por sus siglas en inglés), una herramienta que permite la mutagénesis in vivo inducible y dirigida de loci genómicos de hasta 55 kilobases. CoMuTER emplea la helicasa Cas3, enzima distintiva del sistema CRISPR-Cas clase 1 tipo I-E, fusionada a una citidina desaminasa para desenrollar y mutar grandes extensiones de ADN a la vez, incluidas vías metabólicas completas. La herramienta aumenta en un 350 veces el número de mutaciones en la región objetivo en comparación con el resto del genoma, con un promedio de 0,3 mutaciones por kilobase. Demostramos la idoneidad de CoMuTER para la optimización de vías al duplicar la producción de licopeno en Saccharomyces cerevisiae después de una sola ronda de mutagénesis.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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A Cas3-base editing tool for targetable in vivo mutagenesis

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Imagen de apoyo de  Requirements and challenges for infusion of SHM systems within Digital Twin platforms

Requirements and challenges for infusion of SHM systems within Digital Twin platforms

Por: Héctor José Posada Cárcamo | Fecha: 2023

Abstract: The need for measurable data from physical assets to actively feed a living Digital Twin (DT) is paramount. The requirements and needs that the gathered data should fulfill in order to be practically implemented in the stream data pipeline are heterogeneous, some of them general and other case-specific. This article summarizes a set of identified challenges and requirements for a seamless infusion of well-established Structural Health Monitoring (SHM) systems within DT platforms, without the objective of solve all of them. This identification is performed based on a review of traditional SHM systems with a vast array of information sources as well as on the review of techniques for the systematic digitalization of existing assets. On the other hand, ten real demo cases belonging to Ashvin, an H2020 Research and Innovation project, are providing real world testing beds for an active development of SHM infused in DT systems. Multiple information sources are studied in those sites, which also enriches with more realism, the identification of requirements and challenges presented herein. These assets provide a perspective to researchers about practical implications of these needs.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Requirements and challenges for infusion of SHM systems within Digital Twin platforms

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Imagen de apoyo de  Knowledge graph-based data integration system for digital twins of built assets

Knowledge graph-based data integration system for digital twins of built assets

Por: Carlos; Chacón Ramonell | Fecha: 2023

Abstract: The emergence of digital twin technologies offers a promising avenue for improving decision-making through the integrated use of up-to-date physical or synthetically simulated data. Nevertheless, the practical implementation of digital twins in the built environment remains a significant challenge. This paper describes a system that seamlessly integrates data into digital twins of built assets. The system uses a knowledge graph to achieve data integration, which is designed to be modular, flexible, and interoperable. The graph includes BIM models, metadata from an external IoT platform, and processrelated information. The system is microservice-based and revolves around a graph database housing the knowledge graph. It employs dynamic operations to update the knowledge graph and is tested using civil engineering infrastructure examples. Results from this work can be used to create pipelines that extract and operate with data connecting computational agents integrated into the system as microservices or connected through the system API.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Knowledge graph-based data integration system for digital twins of built assets

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