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In this work, the strength-to-weight ratio on I-beam of a cotton-glass fibers hybrid composite (64% cotton fibers and 36% glass fibers) was assessed. Numerical simulations were carried out under flexural loads and a flexural test were carried out using a Shimadzu AG-X plus 100kN testing machine. The results showed that it is possible to obtain an optimized geometry within the beam through the strategic removal of material zones without compromising the structural integrity. Furthermore, the flexural test on the composite beam showed a higher value in the strength/weight ratio (44) compared to the optimized 6061-T6 aluminum beam (39.65); this behavior can be explained because fiber-reinforced composites are generally less dense compared to metals, and to the distribution of cotton and glass fibers within the beam., En este trabajo se presenta resultados sobre la evaluación de la resistencia/peso en una viga tipo I de material compuesto híbrido con fibras de algodón/vidrio (64% fibras de algodón y 36% fibras de vidrio). Se realizaron simulaciones numéricas a flexión a través del programa ANSYS y una prueba experimental a flexión en la máquina de ensayos Shimadzu AG-Xplus 100kN. Los resultados mostraron que es posible obtener una geometría optimizada dentro de la viga a través de la remoción estratégica de zonas de material sin comprometer la integridad estructural. Además, la prueba experimental a flexión en la viga de material compuesto mostró un valor superior en la relación de resistencia/peso (44) en comparación con la viga optimizada de aluminio 6061-T6 (39.65); este comportamiento se atribuye a que los materiales compuestos reforzados con fibras son generalmente menos densos en comparación con los metales, y a la distribución de las fibras de algodón y vidrio dentro de la viga.

One aspect that affects the strength of Portland cement mortars is the correction of moisture in the mix. Thus, standard techniques are usually used to obtain the absorption value in fine aggregates; one of them is the standard ASTM C128. However, the ASTM C128 presents variability associated with the identification of the saturated surface dry state in the fine aggregates. This research compares the water absorption of four types of Colombian aggregates obtained using the ASTM C128 and an innovative instrumental and analytical technique with the thermogravimetric balance of halogen light (TBHL), coupled with a software that reads the retained water data in real time. The strength of mortars designed on the basis of moisture correction is also evaluated. The absorption results show that TBHL presents lesser dispersion results (not exceeding 10%) than the standard method ASTM C128, indicating greater precision and less uncertainty. Additionally, resources are optimized through TBHL implementation, requiring 25% less time, 86% less energy consumption, and 98% less fine aggregate for a test. Furthermore, the strength of the mortars varies depending on the method used to determine the absorption, as well as the morphology of the aggregates. The accuracy of TBHL allows better correction of the water–cement ratio in the mortars; thus, leading to higher performance., Un aspecto que afecta la resistencia de los morteros de cemento Portland es la corrección por humedad de la mezcla. Se suelen utilizar técnicas estandarizadas para obtener el valor de absorción en áridos finos; una de ellas es la norma ASTM C128. Sin embargo, esta norma presenta una variabilidad asociada a la identificación del estado seco superficial saturado en el árido. En esta investigación se compara la absorción de agua de cuatro tipos de agregados colombianos obtenida mediante la norma ASTM C128 y una innovadora técnica instrumental y analítica con la balanza termogravimétrica de luz halógena (TBHL), acoplada a un software que lee los datos de agua retenida en tiempo real. También se evalúa la resistencia de los morteros diseñados a partir de corrección por humedad. Los resultados de absorción muestran que la TBHL presenta resultados con menor dispersión (no superior al 10%) en comparación a la ASTM C128, lo que indica una mayor precisión y menor incertidumbre. Además, se optimizan recursos mediante la aplicación del TBHL, requiriendo un 25% menos de tiempo, un 86% menos de consumo de energía y un 98% menos de áridos finos para un ensayo. La resistencia de los morteros varía en función del método utilizado para determinar la absorción, así como de la morfología de los áridos. La precisión del TBHL permite una mejor corrección de la relación agua-cemento en los morteros, lo que conduce a un mayor rendimiento.

In this article, a smart inverter model that executes ancillary services with automated decisions is presented, such as powersharing and voltage and frequency stabilization, compensation of unbalance voltage, mitigation of harmonic content, and thebalance of generation and demand. The droop control was utilized for power-sharing between the distributed generations; themitigation of negative-sequence voltage is used for unbalanced voltage compensation, and finally, a feed-forward current isadopted for harmonic compensation. Therefore, the smart inverter was controlled through a supervisory system, identifyingwhich ancillary function to activate at certain times. Results show the successful operation of the system and can be used asvalidation of the proposed control strategies, including the automated decisions in the microgrid, De tre sista författarna delar sistaförfattarskapet.

The text seeks to inquire about the valuation of Johann Sebastian Bach in music education at the university level. To this end, the role of the composer's work in the teaching of traditional stringed instruments from the Colombian Andean region, instruments that are part of a musical tradition different from the Central European one, was analyzed. Based on some contributions of postcolonial theory, especially the notion of provincializing Europe, proposed by Dipesh Chakrabarty, the authors propose the need to provincialize the most mentioned of the great composers and, in general, the Central European musical tradition. In relation to the methodology, surveys were conducted with students and teachers of instruments such as the Andean charango, tiple and bandola, belonging to two Colombian universities, with the intention of finding out how much Bach's music is or is not used in the teaching-learning process and, more importantly, what justifications are given for it. The results show that the symbolic weight of Bach's work is still very strong, even in the teaching of instruments far removed from the Central European tradition, which is why we propose a provincialization of Bach and his work in order to think about its use in a more critical way., O texto busca investigar a valorização de Johann Sebastian Bach na educação musical em nível universitário. Para tanto, foi analisado o papel atribuído à obra do compositor no ensino de instrumentos de corda tradicionais da região andina colombiana, instrumentos quefazem parte de uma tradição musical diferente da centro-europeia. Com base em algumas contribuições da teoria pós-colonial, especialmente a noção de provincialização da Europa, proposta por Dipesh Chakrabarty, os autores propõem a necessidade de provincializar o mais mencionado dos grandes compositores e, em geral, a tradição musical da Europa Central. Com relação à metodologia, foram realizadas pesquisas com alunos e professores de instrumentos como charango, tiple e bandola andinos, pertencentes a duas universidades colombianas, com a intenção de descobrir o quanto a música de Bach é ou não utilizada nos processos de ensino-aprendizagem e, mais importante, quais são as justificativas para isso. Os resultados mostram que o peso simbólico da obra de Bach continua sendo muito forte, mesmo no ensino de instrumentos distantes da tradição centro-europeia, razão pela qual se propõe uma provincialização de Bach e de sua obra para pensar seu uso de forma mais crítica, El texto busca indagar acerca de la valoración que se hace de Johann Sebastian Bach en la educación musical a nivel universitario. Para ello, se analizó el papel que se le da a la obra del compositor en la enseñanza de instrumentos de cuerda tradicionales de la zona Andina colombiana, instrumentos que hacen parte de una tradición musical diferente a la centroeuropea. A partir de algunos aportes de la teoría poscolonial, especialmente de la noción de provincializar Europa, propuesta por Dipesh Chakrabarty, los autores plantean la necesidad de provincializar al más mencionado de los considerados grandes compositores y, en general, a la tradición musical centroeuropea. En relación con la metodología, se realizaron encuestas a estudiantes y docentes de instrumentos, como el charango, tiple y bandola andinas, pertenecientes a dos universidades colombianas, con la intención de indagar qué tanto se usa o no la música de Bach en los procesos de enseñanza-aprendizaje y, más importante aún, qué justificaciones se esgrimen para ello. Los resultados muestran que el peso simbólico de la obra de Bach sigue siendo muy fuerte, incluso en la enseñanza de instrumentos muy alejados de la tradición centroeuropea, por lo cual se propone una provincialización de Bach y su obra parapensar su uso de una forma más crítica.

The field of research in technological capacities is one of the fundamental areas that provides competitiveness and innovation to companies, industries and clusters dedicated to various economic activities. The purpose of this article is to classify firms in the metalworking information sectors in the state of Sonora, Mexico, according to the levels of technological capabilities they present. The methodology was based on a quantitative approach and the deductive method, to define a correlational type of research, with a non-experimental and cross-sectional design. A sample of 116 companies was used, from which information was collected on 35 variables and indicators that were analyzed using multivariate statistics. The main result was the categorization of the group of companies into three layers of Technological Capacity: Basic, intermediate and advanced. It is concluded that these categorization levels are the basis for designing policies for a competitive scaling route for the companies investigated., El campo de la investigación en capacidades tecnológicas es una de las áreas fundamentales que aporta competitividad e innovación a empresas, industrias y clúster dedicados a diversas actividades económicas. El presente artículo tiene como objetivo realizar una clasificación de las firmas de los sectores metalmecánicos y de información del estado de Sonora, México, según los niveles de las capacidades tecnológicas que presentan. La metodología se basó en un enfoque cuantitativo y el método deductivo, para definir una investigación de tipo correlacional, con un diseño no experimental y transversal. Se utilizó una muestra de 116 empresas de las cuales se recolectó información sobre 35 variables e indicadores que fueron analizados mediante estadística multivariada. Como resultado principal se obtuvo la categorización del grupo de empresas en tres estratos de Capacidad Tecnológica: Básico, intermedio y avanzado. Se concluye que dichos niveles de categorización son la base para diseñar políticas de una ruta de escalamiento competitivo para las empresas investigadas.

The University of Cuenca has several cultural facilities: a theater, a museum, auditoriums, libraries, and maintains a direct urban link with the historic El Vado neighborhood, where it has five heritage houses, including Casa Moreno. Currently, the Casa Moreno, acquired in 2009, is uninhabited and the others are partially occupied by offices of different university departments, which makes urban life passive in its immediate context, since administrative activities limit interaction with the community. In the same way, the houses do not have a spatial connector or a program that integrates and connects them. Under these conditions, the research proposes the preliminary design of a cultural center in Casa Moreno that integrates into the program of Corredor Cultural UCuenca, starting in April 2023 and developed in parallel with this research project, which aims to revitalize the University’s heritage houses to serve the whole community through the implementation of mixed uses dedicated to art and culture. The study begins with the exploration of basic concepts that allow a general understanding of the urban and architectural characteristics of cultural projects, as well as their objectives and effects on the city and its heritage. Next, the architectural program is built, supported by an interdisciplinary methodology guided by the Department Ciudad Universitaria, by the analysis of the immediate urban environment, the review of the regulations and the documentary and architectural analysis of Casa Moreno. Finally, the intervention criteria are established through the application of restoration theories and case studies. The proposal for the new Cultural Center in Casa Moreno is closely related to the activity plan of the UCuenca Cultural Corridor project. At the same time, it aims to adapt to the dynamics of the neighborhood while exploring and enhancing the spatial qualities of the house. The project involves a close relationship with artistic activities, facilitati

Introduction. For over a century, Sporothrix schenckii was considered the sole species responsible for sporotrichosis. In 2007, scientific community confirmed the disease could be caused by various Sporothrix species. These species differed in their virulence factors and their antifungal sensitivity.Objective. This study aims to characterize 42 Colombian clinical isolates of Sporothrix spp. phenotypically and genotypically.Material and methods. Forty-two clinical isolates were characterized using phenotypic methods. It involved various culture media to determine their growth range at different temperatures and to assess the type and distribution of pigment and colony texture. Microscopic morphology was evaluated through microcultures, as well as the conidia diameter, type of sporulation, and morphology. Additionally, the assimilation of carbohydrates was selected as a physiological trait for species identification. Genotyping of 40 isolates was performed through partial amplification of the calmodulin gene, followed by sequence analysis.Results. Molecular studies enabled the identification of 32 isolates of S. schenckii and 8 isolates of S. globosa. The combination of phenotypic and genotypic methods eased these species characterizations and the recognition keys development based on parameters such as growth diameter at 25 and 30 ºC, colony texture (membranous or velvety) on potato dextrose agar, and microscopic morphology with predominance of pigmented triangular, elongated oval globose, or subglobose conidia.Conclusions. Confirmation of the phenotypic characteristics and molecular analysis is crucial for identifying Sporothrix species and determining adequate treatment. This study represents the first phenotypical and genotypical characterization of clinical isolates of Sporothrix spp. reported in Colombia., Introducción. Por más de un siglo se creyó que Sporothrix schenckii era la única especie responsable de la esporotricosis. Sin embargo, en el 2007, se consideró que podría ser causada por diferentes especies de Sporothrix, que difieren en sus factores de virulencia y su sensibilidad a los antifúngicos.Objetivo. Caracterizar fenotípica y genotípicamente 42 aislamientos clínicos colombianos de Sporothrix spp.Materiales y métodos. Se caracterizaron 42 aislamientos clínicos mediante métodos fenotípicos. Se usaron varios medios de cultivo para determinar el rango de crecimiento a diferentes temperaturas, el tipo y la distribución del pigmento, y la textura de las colonias. Se evaluó la morfología microscópica por microcultivos mediante la determinación del diámetro, el tipo de esporulación y la morfología de las conidias. La asimilación de carbohidratos se usó como una característica fisiológica para identificar las especies. La genotipificación de los 40 aislamientos se llevó a cabo mediante la amplificación parcial del gen que codifica para la calmodulina y se confirmó por secuenciación.Resultados. Mediante estudios moleculares, se identificaron 32 aislamientos de S. schenckii y ocho de S. globosa. La combinación de métodos fenotípicos y genotípicos permitió caracterizar las especies y construir claves para su reconocimiento, con base en parámetros como el diámetro de crecimiento a 25 y 30 ºC, la textura de las colonias (membranosa, aterciopelada) en agar papa dextrosa y la morfología microscópica con predominio de conidias (triangulares pigmentadas, ovales globosas elongadas, subglobosas).Conclusiones. La caracterización fenotípica y los análisis moleculares son necesarios para identificar las especies de Sporothrix y, de esta forma, elegir el tratamiento indicado. Esta es la primera caracterización fenotípica y genotípica reportada de aislamientos clínicos colombianos de Sporothrix spp.

An intermodal connector involves the creation of a new type of urban infrastructure that has been little explored, whose challenge involves implementing it within a built and consolidated environment such as the streets of a neigh- borhood. While this urban piece serves the need to con- nect different modes of transportation and take advanta- ge of existing infrastructure, the experience of this project determines the possibility of conceiving it as a transitional place that functions as a foyer where modal exchange takes place, understanding “place” as the space in which things happen and daily life occurs. The challenge of implanting an urban element of these cha- racteristics within a mixed neighborhood context, with a de- fined dynamic and character, requires rethinking the social dimension, mediating the interests of the parties involved and projecting from a much more intimate perspective. The project is a description of the experience in the Los Álamos neighborhood, in which the Action-Oriented Planning me- thodology is taken as a starting point to rethink the concept of architectural project and the traditional processes that it implies; proposing new resources, processes, and tools that complement it.

Image analysis techniques can be used to detect and interpret the degradation processes that a material undergoes and to help identify the causes and mechanisms of degradation. Structures and morphological changes are also analysed to establish hypotheses about physical changes. Together with complementary analytical techniques, chemical and mineralogical changes can be evaluated. The methodological process consists of a sequential simplification of the initial micrograph: segmentation of the image, cleaning and isolation of the crack from associated elements, and crack skeletonisation. This method allows the previous image to be processed, thus successfully isolating the microcracks. It is also valid for their quantification.