Obtención de recubrimientos de carburos ternarios y cuaternarios por medio de la técnica de difusión termo-reactiva (TRD), y caracterización de la resistencia al desgaste frente a un recubrimiento de diamante policristalino conforme a la técnica de Pin on Disc.

La industria metalmecánica y especialmente las herramientas de corte están enfrentadas diariamente a problemas de desgaste y corrosión en sus diferentes procesos productivos. Estos problemas se ven reflejados directamente en la vida útil de los componentes y en pérdidas de rendimiento por fallas prematuras. Aunque existen materiales con propiedades de alta dureza y propiedades anti desgaste los costos de estos son muy elevados lo que no los hacen accesibles a todo tipo de industria. Actualmente en la industria estos inconvenientes son solucionados depositando recubrimientos duros sobre los aceros, de esta forma se mejoran las propiedades mecánicas tales como la dureza superficial, la resistencia al desgaste y la resistencia a la corrosión de los materiales recubiertos especialmente aceros con medio y alto contenido de Carbono. En esta oportunidad la investigación fue enfocada en la obtención de recubrimientos de carburos ternarios y cuaternarios sobre acero AISI D2 utilizando elementos formadores de carburos como Niobio, Vanadio y Cromo, mediante la técnica de deposición por difusión termo reactiva (thermoreactive deposition-diffusion TRD), con el fin de caracterizarlos y hacer un estudio comparativo de sus propiedades de resistencia al desgaste frente a los cortadores de una broca con recubrimiento de Diamante Policristalino (PDC). Para la caracterización de los resultados obtenidos se utilizó análisis de microscopia electrónica de barrido SEM (Scanning Electron Microscope), para medir el espesor y caracterizar la morfología de los recubrimientos, análisis de difracción de rayos XRD (X-Ray Diffraction), para definir las fases presentes, el tamaño del cristalito y las micro deformaciones, así como la resistencia al rayado para determinar el desgaste de las capas obtenidas

Relationship between force signal and superficial electromyographic signals associated to hand movements

The analysis of electromyographic signals is applied both to the diagnosis of pathologies and to the recognition of movement patterns. Variables such as force and speed of movement are factors that affect the characteristics of the signals of surface electromyography (SMEG). The naturalness of the movements of the hand are also associated with strength and speed. Current work assessment 96 records of SEMG -Force). The objective was to obtain a linear model that would allow the relation of the force signal with the tone of the forearm SEMG signals. The work results show models at the determination coefficient R2 - median 0.78. The SEMG signal would contribute to the variation of the strength signal. However, there are appreciable differences in relation to the model in each type of hand movement

Design and construction of a solar tracking system for Linear Fresnel Concentrator

An open circuit solar tracking system has been designed, manufactured, simulated and implemented for a handcrafted prototype of a small scale linear Fresnel reflector with a single axis of motion. The electronic control system is governed by an Arduino UNO R3 board and two main auxiliary systems; a Microstep Driver TB6600 and an RTC DS1302 module. Further, a mechanism was implemented that joins the reflectors to a stepper motor that executes a single movement per sequence, to move the set of reflector mirrors that make up the reflection system of the device. The positioning angles of the reflectors determined by the control algorithm models for solar tracking, allowed to feed the TONATIUH software to evaluate the path of the solar rays through the 3D modeling of the Linear Fresnel reflector on a real scale. The software was designed to follow the path of the sun by means of astronomical equations. In this way, the mirrors of the Linear Fresnel reflector can follow the solar path on a single axis from 7 am to 5 pm, making changes in the position of each element in 15-minute intervals. The percentage of position deviation of the reflectors does not exceed 1% between the location of the full-scale system mirrors and the position angles provided by the control algorithm. The efficiency of the implemented automatic solar tracking system increased by more than 50% compared to the manual tracking system

Propuesta manual de servicios para biblioteca enfocado en el sistema de gestión de calidad (SGC) de la Universidad Libre

Este artículo da a conocer la importancia de la implementación de un manual de servicios en una biblioteca universitaria teniendo en cuenta los aspectos actuales incluidos en la norma ISO 9001:2015 el campo de interés está centrado en el apartado 8.6 donde incorpora Control de la producción de bienes y prestación de servicios, con base en la descripción, los autores contextualizan los componentes actuales del SGC, proyectan un manual de servicios teniendo en cuenta tres herramientas administrativas, pensando en la homogeneidad de los servicios a nivel nacional, concluyendo que existen a través de la norma de calidad mecanismos que ayuden en el aprovechamiento de los recursos con los que se cuentan, teniendo como objetivo la calidad del servicio.This article discloses the importance of implementing a service manual in an university's library, taking into account the current ISO 9001: 2015 norm, its main focus centers around numeral 8.6 of the norm which incorporates the control of production goods and services, based on the description, the authors contextualize the current components of the QMS, and project a service manual keeping in mind administrative tools (software), to maintain homogeneity of nationwide services, concluding throughout the norm, the existence of mechanisms to help harness the resources they have, aiming at the quality of services and their continued improvemen

Edificios nZEB, análisis de la tendencia de investigación

In this paper, the research trend in relation to the NZEB buildings is explored, through the analysis of selected scientific articles published in 11 journals collected in chronological order from 2014 to 2020. The analysis is carried out on the basis and terms of annual investigative publications of the documents in relation to the NZEB, such as contributions made by countries, institutions, authors, and research topics covered. The study carried out uses a document review methodology. The analysis reveals a growing interest in energy efficiency research in recent times, implying that the importance that the construction industry attaches to NZEB in consequences of global warming and accelerating environmental problems. The findings also indicate that, during the period studied, researchers in developed economy areas such as the US and Italy contributed higher rates to promoting research on NZEB. Developing countries like China also went to great lengths to promote research. Research topics covered tend to focus on studies completed with NZEB project delivery and development, building rehabilitation, energy performance, and advanced technologies applied for energy improvement in buildings. This research provides a valuable platform for industry professionals and researchers to understand NZEB construction research trends and developments, including their applicability and their future research and contributions to the topic.En el presente trabajo se exploran la tendencia de investigación con relación a los edificios NZEB, mediante el análisis de artículos científicos seleccionados publicados en 11 revistas recopilados en orden cronológico desde el año 2014 hasta el 2020. El análisis se realiza en base y términos de publicaciones investigativas anuales de los documentos con relación a los NZEB, como contribuciones realizadas por países, instituciones, autores, y temas de investigación cubiertos. El estudio realizado utiliza una metodología de revisión documental. El análisis revela un creciente interés de investigación de rendimiento energético en los últimos tiempos, lo que implica la importancia que la industria de la construcción atribuye a NZEB en consecuencias al calentamiento global y problemática ambiental se está acelerando. Los hallazgos también indican que, durante el período estudiado, los investigadores de las zonas con economías desarrolladas como los EE. UU., e Italia contribuye-ron con índices más altos a promover la investigación sobre NZEB. Los países en desarrollo como China también hicieron grandes esfuerzos para promover la investigación. Los temas de investigación cubiertos tienden a centrarse en los estudios finalizados con la entrega y el desarrollo de proyectos de NZEB, rehabilitación de edificios, rendimiento energético y tecnologías avanzadas que se aplican para el mejoramiento energético en las edificaciones. Esta investigación proporciona una plataforma valiosa para que los profesionales e investigadores de la industria comprendan las tendencias y los desarrollos de investigación de la construcción NZEB, incluida su aplicabilidad, sus futuras investigaciones y contribuciones al tema

Edificios nZEB, análisis de la tendencia de investigación

In this paper, the research trend in relation to the NZEB buildings is explored, through the analysis of selected scientific articles published in 11 journals collected in chronological order from 2014 to 2020. The analysis is carried out on the basis and terms of annual investigative publications of the documents in relation to the NZEB, such as contributions made by countries, institutions, authors, and research topics covered. The study carried out uses a document review methodology. The analysis reveals a growing interest in energy efficiency research in recent times, implying that the importance that the construction industry attaches to NZEB in consequences of global warming and accelerating environmental problems. The findings also indicate that, during the period studied, researchers in developed economy areas such as the US and Italy contributed higher rates to promoting research on NZEB. Developing countries like China also went to great lengths to promote research. Research topics covered tend to focus on studies completed with NZEB project delivery and development, building rehabilitation, energy performance, and advanced technologies applied for energy improvement in buildings. This research provides a valuable platform for industry professionals and researchers to understand NZEB construction research trends and developments, including their applicability and their future research and contributions to the topic.En el presente trabajo se exploran la tendencia de investigación con relación a los edificios NZEB, mediante el análisis de artículos científicos seleccionados publicados en 11 revistas recopilados en orden cronológico desde el año 2014 hasta el 2020. El análisis se realiza en base y términos de publicaciones investigativas anuales de los documentos con relación a los NZEB, como contribuciones realizadas por países, instituciones, autores, y temas de investigación cubiertos. El estudio realizado utiliza una metodología de revisión documental. El análisis revela un creciente interés de investigación de rendimiento energético en los últimos tiempos, lo que implica la importancia que la industria de la construcción atribuye a NZEB en consecuencias al calentamiento global y problemática ambiental se está acelerando. Los hallazgos también indican que, durante el período estudiado, los investigadores de las zonas con economías desarrolladas como los EE. UU., e Italia contribuye-ron con índices más altos a promover la investigación sobre NZEB. Los países en desarrollo como China también hicieron grandes esfuerzos para promover la investigación. Los temas de investigación cubiertos tienden a centrarse en los estudios finalizados con la entrega y el desarrollo de proyectos de NZEB, rehabilitación de edificios, rendimiento energético y tecnologías avanzadas que se aplican para el mejoramiento energético en las edificaciones. Esta investigación proporciona una plataforma valiosa para que los profesionales e investigadores de la industria comprendan las tendencias y los desarrollos de investigación de la construcción NZEB, incluida su aplicabilidad, sus futuras investigaciones y contribuciones al tema

Evaluation of a cocoa dryer prototype using LabVIEW software and Arduino hardware

In a country like Colombia, food drying plays an important role in the extension of technology so that farmers improve the quality of their productivity. The objective of this work is to develop a system for acquiring thermodynamic variables, to establish the energy efficiency of a product drying oven, specifically for cocoa beans using Arduino hardware and LabView software. This research begins by establishing the variables to be measured and recorded by the DHT11 sensors, such as temperature and humidity. These sensors are connected to an Arduino Uno board that has an Atmel microcontroller, which captures the information from each of these. An algorithm was also developed that captures the temperature and humidity data and sends it through the serial port to the LabView software, in which the visualization on the front panel and programming in the block diagram have been developed, being viewed from the HMI (Human Machine Interface). For the experimental tests, 3,309 grams of fermented cocoa beans were taken, and dried for 36 hours, removing a total mass of water of 1,650 grams. The results show an energy efficiency of 10.62%, concluding that the drying oven that takes advantage of the residual heat of an 18000 BTU condenser integrated with the proposed variable system is suitable for drying cocoa beans. Despite this efficiency being low, it meets the objective of removing moisture from them

<i>piggyBac </i>transposons expressing full-length human dystrophin enable genetic correction of dystrophic mesoangioblasts

Duchenne muscular dystrophy (DMD) is a genetic neuromuscular disorder caused by the absence of dystrophin. We developed a novel gene therapy approach based on the use of the piggyBac (PB) transposon system to deliver the coding DNA sequence (CDS) of either full-length human dystrophin (DYS: 11.1 kb) or truncated microdystrophins (MD1: 3.6 kb; MD2: 4 kb). PB transposons encoding microdystrophins were transfected in C2C12 myoblasts, yielding 65±2% MD1 and 66±2% MD2 expression in differentiated multinucleated myotubes. A hyperactive PB (hyPB) transposase was then deployed to enable transposition of the large-size PB transposon (17 kb) encoding the full-length DYS and green fluorescence protein (GFP). Stable GFP expression attaining 78±3% could be achieved in the C2C12 myoblasts that had undergone transposition. Western blot analysis demonstrated expression of the full-length human DYS protein in myotubes. Subsequently, dystrophic mesoangioblasts from a Golden Retriever muscular dystrophy dog were transfected with the large-size PB transposon resulting in 50±5% GFP-expressing cells after stable transposition. This was consistent with correction of the differentiated dystrophic mesoangioblasts following expression of full-length human DYS. These results pave the way toward a novel non-viral gene therapy approach for DMD using PB transposons underscoring their potential to deliver large therapeutic genes.status: publishe

A parabolic solar collector for harnessing solar energy in Bucaramanga, Colombia

In this work, a solar energy collection system based on a parabolic solar collector adjusted to the conditions and availability of energy was designed to examine this type of collection device and evaluate the energy potential when installed in an educational institution. To do this, data from the historical series of solar radiation compiled by the POWER project (Prediction of Worldwide Energy Resources) were analyzed and compared with data from the Institute of Hydrology, Meteorology and Environmental Studies in Colombia (IDEAM)

Fc galactosylation follows consecutive reaction kinetics and enhances immunoglobulin G hexamerization for complement activation

Fc galactosylation is a critical quality attribute for anti-tumor recombinant immunoglobulin G (IgG)-based monoclonal antibody (mAb) therapeutics with complement-dependent cytotoxicity (CDC) as the mechanism of action. Although the correlation between galactosylation and CDC has been known, the underlying structure–function relationship is unclear. Heterogeneity of the Fc N-glycosylation produced by Chinese hamster ovary (CHO) cell culture biomanufacturing process leads to variable CDC potency. Here, we derived a kinetic model of galactose transfer reaction in the Golgi apparatus and used this model to determine the correlation between differently galactosylated species from CHO cell culture process. The model was validated by a retrospective data analysis of more than 800 historical samples from small-scale and large-scale CHO cell cultures. Furthermore, using various analytical technologies, we discovered the molecular basis for Fc glycan terminal galactosylation changing the three-dimensional conformation of the Fc, which facilitates the IgG1 hexamerization, thus enhancing C1q avidity and subsequent complement activation. Our study offers insight into the formation of galactosylated species, as well as a novel three-dimensional understanding of the structure–function relationship of terminal galactose to complement activation in mAb therapeutics