Smartphones on the air track. Examples and difficulties

In this paper we describe a classical experiment with an air track in which smartphones are used as experimental devices to obtain physical data. The proposed experiment allows users to easily observe and measure relationships between physical magnitudes, conservation of momentum in collisions and friction effects on movement by utilizing the users’ own mobile devices

Caracterización del sistema de excitación de una máquina síncrona

El control de la tensión de una máquina sincrónica se realiza modificando la corriente de su devanado de campo. Para tal fin se requiere de una excitatriz la cual en este trabajo está conformada por un circuito rectificador monofásico basado en tiristores. Para conseguir un buen diseño desde el punto de vista del control, se requiere de su caracterización, la cual es obtenida usando una función trigonométrica inversa, que es la usada en este trabajo.Voltage control in a synchronous machine is made modifying the current of the field winding. One exciter circuit based in thyristor circuit rectifier is required to control the field current. To get a good design since the control viewpoint, is necessary a characterization with an inverse trigonometric function, as used in this paper

Estabilidad de sistemas difusos con lmis

Se presenta un método para aproximar el modelo de una planta no lineal mediante reglas difusas del tipo Takagi – Sugeno y se aplica una metodología para el diseño de un compensador y un observador difusos empleando desigualdades lineales matriciales (LMI’s). Estos métodos son aplicados mediante simulación en un péndulo invertido para modelado difuso Takagi – Sugeno con dos, cuatro y seis reglas. Los resultados encontrados son comparados con los que se obtienen al reubicar los polos del compensador y el observador difusos

El proceso constructivo de los teatros del canal del arquitecto Juán Navarro Baldeweg

El artículo que se presenta estudia y valora el sistema constructivo, y su desarrollo, de las obras de los Teatros del Canal, obra del Catedrático de Proyectos de la Escuela de Arquitectura de Madrid, Prof. Navarro Baldeweg, que se están llevando a cabo en Madrid, siendo la Promotora y Propietaria el Canal de Isabel II de la Comunidad Autónoma de Madrid. Se trata de un conjunto de tres edifi cios, dos teatros y un centro coreográfi co, cada uno con soluciones constructivas diferenciadas. Este artículo es el resultado del trabajo llevado a cabo durante el Curso 2006- 07 en el Seminario de “Industrialización de la Construcción”, que bajo la dirección del Catedrático Prof. del Águila se desarrolla dentro del Programa de Doctorado del Departamento de “Construcción y Tecnología Arquitectónicas” de la Universidad Politécnica de Madrid. El trabajo comprende dos partes bien diferenciadas: La primera de introducción, prólogo (redactado por el Prof. Navarro) y una descripción general de los edifi cios; la segunda, desarrollando las diferentes partes constructivas del mismo, desde los distintos tipos de estructuras utilizados, pasando por las fachadas “colgadas” a modo de telones, a los aspectos múltiples de interior, desde la acústica, al mobiliario especial y a los acabados y todo ello no puramente descriptivo, sino también de una manera crítica para que sirva como una consecuencia con valor didáctica para los alumnos-autores. - This present article studies and chriticizes the building system and the developement of the theater and dance complex of Canal (Teatros del Canal, Madrid), designed by Juan Navarro Baldeweg, Principal Professor of Architectural Design at Madrid School of Architecture Polytechnic University. These theaters are being built in the center of Madrid city. The owner and developer of this complex is Canal de Isabel II (the water supply company of Madrid regional Government). The project consist in a three building complex, two theatres and a choreographic centre, put together by a back service block, each of them with it’s own different building solutions. This article is the result of the work done during the term 2006-07 of the Seminar of “Industrialization of Building Process” that, under the direction of the Principal Professor Alfonso del Águila, takes place within the Ph. D. Program of the Department of Construction and Architectural Technology set in Madrid School of Architecture Polytechnic University. The work includes two different parts: the fi rst one, which introduces is a prologue written by Prof. Navarro and a general description of the building. The second part describes its different construction areas, ranging from the different structural solutions, the hung façades pretending to be theatre curtains, some aspects of the interior design, as acoustics, special furniture and fi nishes, not in a mere descriptive way, but also from a critical manner with the intention to be a consequence with didactical value for the students/ authors

Caracterización del sistema de excitación de una máquina síncrona

El control de la tensión de una máquina sincrónica se realiza modificando la corriente de su devanado de campo. Para tal fin se requiere de una excitatriz la cual en este trabajo está conformada por un circuito rectificador monofásico basado en tiristores. Para conseguir un buen diseño desde el punto de vista del control, se requiere de su caracterización, la cual es obtenida usando una función trigonométrica inversa, que es la usada en este trabajo

Comparative Extraction of Phenolic Compounds from Olive Leaves Using a Sonotrode and an Ultrasonic Bath and the Evaluation of Both Antioxidant and Antimicrobial Activity

This study is part of the project SHEALTHY that has received funding from European Union's Horizon 2020 Research and Innovation Programme under grant agreement No 817936. This study was also supported by project RTI2018-099835-A-I00 financed by MCIN/AEI/10.13039/5011000 11033/FEDER "Una manera de hacer Europa".A sonotrode ultrasound-assisted extraction of phenolic compounds from olive leaves has been developed using a Box-Behnken design to optimize the effects of solvent composition and ultrasound parameters. The determination of single phenolic compounds was performed by HPLC-MS and the highest recovery in total compounds, oleuropein and hydroxytyrosol was achieved using EtOH/H2O (55:45, v/v), 8 min and 100% of amplitude. The optimal conditions were applied on leaves from seven olive cultivars grown under the same conditions and the results were compared with those found by using a conventional ultrasonic bath, obtaining no statistical differences. Moreover, antioxidant activity by FRAP, DPPH and ABTS in these olive leaf extracts was evaluated and they exhibited a significant correlation with oleuropein and total phenolic content. All cultivars of olive leaf extracts were found to be active against S. aureus and methicillin-resistant S. aureus with minimum bactericidal concentration (MBC) values) that ranged from 5.5 to 22.5 mg mL(-1). No extracts showed antimicrobial activity against C. albicans. The percentages of mycelium reduction in B. cinerea ranged from 2.2 and 18.1%. Therefore, sonotrode could be considered as an efficient and fast extraction technique that could be easily scaled-up at industrial level, thus allowing for olive leaves to be revalorized.European Union's Horizon 2020 Research and Innovation Programme 817936MCIN/AEI/FEDER "Una manera de hacer Europa" RTI2018-099835-A-I0

AGENCIA DE AUTOCUIDADO Y APRENDIZAJE A TRAVÉS DE PROBLEMAS EN ESTUDIANTES DE ENFERMERÍA

La agencia de autocuidado es fundamental en la ciencia de enfermería. Asimismo, el aprendizaje a través de problemas ha sido utilizado por los maestros de la profesión como estrategia didáctica que permite el desarrollo de algunas competencias de los futuros enfermeros. Objetivo: determinar la relación entre la agencia de autocuidado y el aprendizaje a través de problemas de los estudiantes de enfermería de una universidad de Bucaramanga - Colombia. Métodología: La investigación es de tipo analítico de corte transversal. La muestra fue de 127 estudiantes de enfermería en pregrado. Se realizó la recolección de datos a través de la escala de valoración de agencia de autocuidado derivada de la teoría de Dorothea Orem. Resultados: existe relación estadísticamente significativa entre la agencia de autocuidado y las fases de resolución de problemas. Conclusiones: los estudiantes distinguieron características que se deben tener en cuenta al establecer la estrategia del aprendizaje basado en problemas como son: la motivación, el manejo del tiempo y la certeza que todos los estudiantes entiendan el problema

Effect of Lactic Acid Bacteria Fermentation on the Polar Compounds Content with Antioxidant and Antidiabetic Activity of Avocado Seed Extracts

Avocado seeds, a common waste in the avocado processing industry, have been found to have several bioactivities, such as anticancer, antimicrobial, hypocholesterolemic, antioxidant, and antidiabetic activities, among others. Nowadays, this wastage is causing an environmental problem, so the use of new technologies to take advantage of it is a novel field of research. In this study, the submerged fermentation by lactic acid bacteria was used as a novel tool for improving the bioactive compound extraction from avocado seeds. Avocado seeds were fermented by different strains, their polar compounds were identified and quantified by HPLC-ESI-TOF-MS, the antioxidant activity was measured by DPPH and FRAP assays, and the antidiabetic activity was analyzed by the alpha-amylase assay. A total of 32 polar compounds were identified, with 13 of them being described in avocado seeds for the first time. Avocado seeds fermented by Pentosaceus acidilactici showed the highest sum of polar compounds (6279.63 67.74 g/g d.w.), and by extension, of hydroxytyrosol glucoside (2989.76 3.64 g/g d.w.). Lactiplantibacillus plantarum CECT 9567 showed the highest antioxidant activity measured by both DPPH and FRAP assays (6294.67 19.44 and 6846.91 2.13 g TE/g d.w., respectively). Furthermore, Lactiplantibacillus plantarum CECT 748T had the highest antidiabetic activity (52.15% 0.67% inhibition of alpha-amylase activity), attributable to the polyphenols. According to the results, submerged fermentation by lactic acid bacteria led to an interesting increase of the polar compounds’ extractability of avocado seeds, consequently improving the bioactivities of the extracts, which could then be used for food nutraceutical or cosmetic purposes.Project RTI2018-099835-A-I00MCIN/AEI/ 10.13039/501100011033/FEDER, “Una manera de hacer Europ

Deep Sequencing of the Mexican Avocado Transcriptome, an Ancient Angiosperm with a High Content of Fatty Acids

Background: Avocado (Persea americana) is an economically important tropical fruit considered to be a good source of fatty acids. Despite its importance, the molecular and cellular characterization of biochemical and developmental processes in avocado is limited due to the lack of transcriptome and genomic information. Results: The transcriptomes of seeds, roots, stems, leaves, aerial buds and flowers were determined using different sequencing platforms. Additionally, the transcriptomes of three different stages of fruit ripening (pre-climacteric, climacteric and post-climacteric) were also analyzed. The analysis of the RNAseqatlas presented here reveals strong differences in gene expression patterns between different organs, especially between root and flower, but also reveals similarities among the gene expression patterns in other organs, such as stem, leaves and aerial buds (vegetative organs) or seed and fruit (storage organs). Important regulators, functional categories, and differentially expressed genes involved in avocado fruit ripening were identified. Additionally, to demonstrate the utility of the avocado gene expression atlas, we investigated the expression patterns of genes implicated in fatty acid metabolism and fruit ripening. Conclusions: A description of transcriptomic changes occurring during fruit ripening was obtained in Mexican avocado, contributing to a dynamic view of the expression patterns of genes involved in fatty acid biosynthesis and the fruit ripening process