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Actualmente la inversión en energías de renovables como la eólica, geotérmica o la solar fotovoltaica se presenta como el camino más confiable para la transición energética a fuentes energéticas de bajo impacto ambiental. Si bien los grandes parques eólicos y solares de generación han dado resultados favorables existen aún muchas áreas de oportunidad para mejorar el rendimiento de generación y minimizar aún más el impacto medioambiental, como es el caso de los sistemas híbridos de generación de energía. El objetivo de este trabajo fue elaborar el prototipo de un sistema híbrido de energía, eólica y fotovoltaica; que nos permita generar energía eléctrica mediante la utilización de energía fuentes renovables como materia prima y de manera más sustentable al reducir emisiones comparada con fuentes de generación tradicionales. Partiendo desde un dimensionamiento previo de las variables climáticas, el diseño del sistema, el armado y las pruebas de funcionamiento de un prototipo que en una misma estructura, contiene un módulo fotovoltaico, un rotor eólico tipo Savonius, un panel de control y sus respectivas unidades de almacenamiento (para este caso de generación fuera de la red local), en donde podemos esperar un menor desgaste en la saturación de la red eléctrica debido a que, al ser sistema híbrido, se utilizan múltiples fuentes, por lo que, si se llega a presentar intermitencia, no se pierde por completo la generación de energía.

En la actualidad existe una problemática relacionada con la falta de modelos de innovación enfocado a las energías renovables, que permitan generar nueva tecnología, lo cual es una solución a la demanda de energía creciente en las últimas décadas. Este articulo presenta el desarrollo de un modelo de innovación enfocado en la generación de tecnologías para la producción de energías renovables. Para ello se analizó el estado del arte de los modelos existentes, lo que permitió observar que no existían modelos aplicables a pequeñas empresas enfocados en este tipo de energías. Se creó un modelo de innovación flexible y de fácil aplicación, el cual integra características de los modelos de red e integrados de cuarta y quinta generación, el cual ya fue puesto a prueba. A diferencia de otros modelos diseñados para empresas de gran tamaño, el modelo propuesto es fácilmente entendible, pudiéndose desarrollar paso a paso, para una aplicación exitosa, y evitando sesgos, presentando una ventaja frente a otros modelos. Este modelo de innovación puede servir de guía para la implementación, creación y mejora de tecnologías para sistemas de generación de energía renovable, y abarca los campos necesarios para tener una gestión de la innovación exitosa.

The chemical composition of COVID test swabs has not been examined beyond the manufacturers’ datasheets. Given the unprecedented demand for swabs to conduct rapid lateral flow tests and nucleic acid amplification tests, which led to mass production, including 3-D printing platforms, it is plausible that manufacturing impurities could be present in the swabs and, if so, could pose a risk for human health. We used scanning electron microscopy and energy dispersive X-ray (EDX) spectroscopy to examine the ultrastructure of five assorted brands of COVID test swabs, and to identify and quantify their chemical elements. We detected unexpected elements, including transition metals, such as titanium and zirconium, as well as aluminium, silicon, and fluorine. The amount of some of the detected elements is close to reported toxicological thresholds for inhalation routes. Experimental studies have shown that detrimental effects of the unexpected chemical elements include moderate to severe inflammatory states in the exposed epithelium as well as proliferative changes. Given the massive testing still being used in the context of the COVID pandemic, often as requisites for travelling, attending universities, or as mandatory work policies, we urge caution in continuing to recommend repeated and frequent testing, particularly of healthy, non-symptomatic, individuals.

Genomics has set the basis for a variety of methodologies that produce high-throughput datasets identifying the different players that define gene regulation, particularly regulation of transcription initiation and operon organization. These datasets are available in public repositories, such as the Gene Expression Omnibus, or ArrayExpress. However, accessing and navigating such a wealth of data is not straightforward. No resource currently exists that offers all available high and low-throughput data on transcriptional regulation in

Three Cu(II) coordination compounds with 4-methyl imidazole were obtained, such as [Cu(C4H6N2)4(NO3)2], [Cu(C4H6N2)4Br2], and [Cu(C4H6N2)4Cl2]. Crystallographic studies confirmed their structural similarity with Cu(II) in the active site of endogenous copper-zinc superoxide dismutase (CuZn-SOD). The superoxide anion radical (O2•-) scavenging activity was evaluated by the non-enzymatic experimental assay and followed the trend [Cu(C4H6N2)4(NO3)2] > [Cu(C4H6N2)4Br2] > [Cu(C4H6N2)4Cl2]. The density functional theory and the hard and soft acids and bases principle showed the importance of the electron-deficient character of Cu(II) in the chemical reactivity of the coordination compounds; Cu(II) is the softest site in the molecule and it is preferred for the nucleophilic and radical attacks of the soft O2•-. A simple rule was obtained: "the electron-deficient character of Cu(II) is the key index for the O2•- scavenging activity and is modulated by the electron-releasing counteranion effect on the coordination compound".

Deep eutectic solvents (DESs) have been considered "the organic reaction medium of the century" because they can be used as solvents and active catalysts in chemical reactions. However, experimental and theoretical studies are still needed to provide information on the structures of DESs, the kinetics and thermodynamics properties, the interactions between the DESs and the substrates, the effect of water on the DES supramolecular network and its physicochemical properties, and so forth. This information is very useful to understand the essence of the processes that take place in the catalysis of chemical reactions and, therefore, to help in the design of a DES for a specific reaction and sample. This article shows a systematic study of the impact of DES choline chloride/p-toluenesulfonic acid and DES choline chloride/p-toluenesulfonic acid-water in the aza-Michael addition of arylamines to maleimide to obtain aminopyrrolidine-2,5-dione derivatives. The derivatives are obtained under very mild reaction conditions with good yield. The global reaction is exothermic, spontaneous, permitted by enthalpy, and prohibited for entropy. The calculated potential energy surface shows a reaction mechanism of six steps controlled by enthalpy (except the last step that is controlled by entropy). The water incorporated in the supramolecular DES complex stabilizes the transition states and favors the enthalpy-driven binding. A set of H/D exchange NMR experiments validates the transition state existing in the fourth stage of the mechanism.

Objectives The aim of this study was to describe a mapping approach for ablation of complex atrial re-entrant tachycardias (ARTs) in which high-density activation maps are transformed into low-density activation maps displaying only the active part of the tachycardia circuit. Background High-density activation maps during complex ARTs are challenging to interpret because they include the activation patterns of active and passive circuits. Entrainment mapping provides the identification of the active tachycardia circuit. However, current electroanatomic mapping systems are not capable of color-coding the information obtained from entrainment maneuvers. Methods Seventeen consecutive patients with atypical atrial flutter were included. A high-density activation map was acquired during index tachycardia. Subsequently, entrainment maneuvers were performed to generate a low-density activation map in which only the activation of the atria directly involved in the flutter circuit was displayed. Results Of all patients included, 82% were men, and their mean age was 62 ± 7 years. Structural heart disease was present in 59%, and 53% had undergone prior left atrial ablation procedures. Low-density activation maps were successfully generated from an average of 14 ± 3 entrainment points. Twenty circuits (95%) were identified in the left atrium and 1 (5%) in the right atrium. Ablation guided by low-density mapping successfully terminated all ARTs in 267 ± 353 s of radiofrequency application. Conclusions Low-density mapping based on entrainment maneuvers provides a precise delineation of the active circuit during complex ARTs and resulted in successful arrhythmia termination. This approach can be easily incorporated into clinical practice.

The nanostructure materials are a prefer option to the high-growth technological changes. The remarkable nanotubes and other carbon nanostructure properties have been theoretically and experimentally tested. These nanostructures can be used as reinforcement materials in composites; the research main challenge is the dispersion of these carbon materials in different matrices caused by cluster formations produced by the intermolecular forces. The aim of this research was the synthesis and characterization of a composite material from carbon nanotubes and styrene oligomers with hydroxyl end groups; and the analysis of their dispersion and mechanical and electrical properties. Pristine and functionalized carbon nanotubes and polystyrene with hydroxyl end groups were synthesized; furthermore, magnetic field was applied to the composites to promote dispersion of carbon nanotubes. The materials were characterized by scanning electron microscopy, FTIR and Raman spectroscopy. The Raman spectroscopy has demonstrated interaction between carbon nanostructures and polymers; this changes their mechanical and electrical properties. The composites formed with functionalized carbon nanotubes (1.6 wt%) have the highest hardness value (91.16 HV), five times over the pristine polymer. As carbon nanostructure concentration increases, the composite acquires conductivity and the electron transport is promoted. The values obtained in the composites qualify them as electromagnetic interference shields, those demand materials with higher electrical conductivity than conventional polystyrene.

Since the discovery of carbon nanotubes, they have been intensely studied as filler materials into different matrices, including polymers to obtaining composites with enhancing properties. Carbon spheres are other type of nanostructures that have not been enough studied as reinforcement material. Polymeric composites with enhanced properties have gradually replaced many of the conventional materials in several areas. In this research, a comparative study of composites based in MWCNTs and CSs incorporated in poly(methyl methacrylate) matrices by mixing solution method was carried out. Composites with 2 wt%, 3 wt%, and 4 wt% of MWCNTs and CSs were obtained through solution mixing and were characterized by scanning electron microscopy (SEM), Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). Carbon sphere composites were observed with better dispersion than carbon nanotube composites through SEM. D, G, and G’ characteristic bands of carbon nanostructures and typical bands of PMMA were observed by Raman spectroscopy in all composites. C–H, C=O, and CH2 vibrations were depicted in composites spectra by FTIR. Vickers microhardness and electrical conductivity of composites were measured. A significant increasing in electrical conductivity was obtained in MWCNTs/PMMA composites, reaching values up to 8.45 × 10–5 S/cm. Nevertheless, the highest electrical conductivity values were observed in CSs composites (7.98 × 10–4 S/cm). Vickers microhardness also was enhanced in all composites; however, CSs/PMMA composites showed the highest values in contrast with MWCNTs/PMMA composites. The major Vickers and electrical conductivity properties of CSs/PMMA composites are attributed to better carbon spheres dispersion into polymer matrix.

El suicidio se ha vuelto una problemática social a nivel mundial al convertirse en la segunda causa de muerte entre la población de entre 15 a 29 años según datos de la OMS. Por lo cual es necesario un instrumento que permite su detección oportuna, se utiliza la prueba de Psicgarcía (2013) la cual se aplica la misma a una población total de 20 personas y posteriormente se modifica para ser estandarizada, dando como resultado una prueba confiable de 51 reactivos.

Genomics has set the basis for a variety of methodologies that produce high-throughput datasets identifying the different players that define gene regulation, particularly regulation of transcription initiation and operon organization. These datasets are available in public repositories, such as the Gene Expression Omnibus, or ArrayExpress. However, accessing and navigating such a wealth of data is not straightforward. No resource currently exists that offers all available high and low-throughput data on transcriptional regulation in Escherichia coli K-12 to easily use both as whole datasets, or as individual interactions and regulatory elements. RegulonDB (https://regulondb.ccg.unam.mx) began gathering high-throughput dataset collections in 2009, starting with transcription start sites, then adding ChIP-seq and gSELEX in 2012, with up to 99 different experimental high-throughput datasets available in 2019. In this paper we present a radical upgrade to more than 2000 high-throughput datasets, processed to facilitate their comparison, introducing up-to-date collections of transcription termination sites, transcription units, as well as transcription factor binding interactions derived from ChIP-seq, ChIP-exo, gSELEX and DAP-seq experiments, besides expression profiles derived from RNA-seq experiments. For ChIP-seq experiments we offer both the data as presented by the authors, as well as data uniformly processed in-house, enhancing their comparability, as well as the traceability of the methods and reproducibility of the results. Furthermore, we have expanded the tools available for browsing and visualization across and within datasets. We include comparisons against previously existing knowledge in RegulonDB from classic experiments, a nucleotide-resolution genome viewer, and an interface that enables users to browse datasets by querying their metadata. A particular effort was made to automatically extract detailed experimental growth conditions by implementing an assisted curation strategy applying Natural language processing and machine learning. We provide summaries with the total number of interactions found in each experiment, as well as tools to identify common results among different experiments. This is a long-awaited resource to make use of such wealth of knowledge and advance our understanding of the biology of the model bacterium E. coli K-12.

In this work, the use of an objective method, the formulation of the Rasch measurement model, which synthesizes data from different susceptible elements for maintenance (SEM) and healthcare units (HU) into a uniform analytical framework, is considered to get representative measures of corrective maintenance demand in an hospital. Thus, information about 10 SEM and 33 HU were obtained from two hospital located in Badajoz (Spain) to be treated. A latent variable, denominated corrective maintenance demand, was defined. It is supposed, and later it is verified, that all SEM previously indicated have a marked influence on the latent variable. The adequate assignment of categorical values across SEM measures and the good fit of the data are checked as a previous phase to properly compute the Rasch measures. After applying the Rasch methodology, it was obtained that the mean corrective maintenance demand of HU is lower than expected, but significative differences between units are apparent. Those which care for high risk patients, as liver transplant, intensive care, and internal medicine, are the most influential units on corrective maintenance demand, getting moreover a ranking of all HU according to their corrective maintenance demand. Similarly, another ranking of all SEM is provided, being hospital furniture the item that exerts the highest influence on corrective maintenance demand. Moreover, the unexpected behaviors, called misfits, of some HU and SEM constitute a very useful information to better know the hospital requirements and correctly allocate the work hours in the maintenance management program. Consequently, the Rasch measurement model is a very useful tool for decision making related to corrective maintenance cost management and their correct attribution to each healthcare unit.