Viewpoint: How the Graphene Could Help to Decrease SARS-CoV-2 Spread?

The COVID-19 (Coronavirus Disease 2019), caused by the SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) began in December 2019 in Wuhan, China. Until February 2021, there are 110 million of infected people, 60 million have recovered and approximately 2.5 million have passed away worldwide according to WHO. The coronavirus pandemic is evolving very rapidly and represents a risk for health care workers and society in general. Moreover, pandemic has tested the limits of health systems by raising questions about forms of prevention, management of infections with conventional therapies and the use of diagnostic tools. In this article we discussed the possible role of the nanostructured-graphene based materials as aid tools for preventing the spread and infection of SARS-CoV-2. In this regard, nanotechnology could take part in the fight against the spread of future diseases caused by deadly viruses. However, its use should be well founded in terms of biocompatibility. Therefore, we have proposed an approach based on graphene nanomaterials as possible allies for the fight against the COVID-19 spread based on the physicochemical features that present these novel nanomaterials

Use of Nanostructured Photocatalysts for Dye Degradation: A Review

Among the technologies proposed for wastewater treatment, the Advanced Oxidation Processes are viable and technological strategies for dyes degradation. Different photocatalytic systems classified in metal oxides alone or combined through hybrid composites or immobilized onto supports have been designed in various nanostructured shapes for their application in the photodegradation of polluting dyes. This review aims to describe the dyes as an environmental threat, photocatalysis as an effective process to remove dyes from water and provide an overview of the recent studies using photocatalytic systems grouped according to their development. Furthermore, this review describes the main parameters of a photocatalytic system with an important role in dye photodegradation. Finally, we discuss the limitations of photocatalysis for real industrial applications and the challenges for this environmental nanotechnology

Autoevaluación y evaluación entre iguales en una asignatura de redes de ordenadores

Con la llegada del EEES se ha fomentado el uso de la evaluación continuada como un ingrediente de la docencia de calidad que permite al alumno mantenerse puntualmente informado de su progreso en el proceso de aprendizaje. Este trabajo se centra en el uso de la autoevaluación y la evaluación entre iguales como base para conseguir esta evaluación continuada. En él detallamos la experiencia, durante los cursos 2008/09 y 2009/10, del uso de estas dos herramientas de aprendizaje en el contexto de una asignatura de redes de ordenadores de tercer curso de Ingeniería Técnica en Informática de Gestión

The First Post-Kepler Brightness Dips of KIC 8462852

We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <<1um, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process

4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil. El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país. La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica. Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas

Translational neuroimaging: brain reorganisation in healthy individuals and patients with psychiatric and neurological conditions

Trabajo presentado en el Seminario Programa de Neurociencias, celebrado onlne el 27 de octubre de 2020

Concepciones acerca de la creatividad desde la formación inicial docente

Creativity plays a fundamental role in education. All over the world, educational institutes are asking teachers to implement a change from traditional pedagogy to be more creative and apply creativity in their teaching activities. However, teachers are often thought to lack the necessary knowledge and skills, to be resistant and slow to change. This study explore the conception of creativity, the experience, reflection and impact in their practice of 54 teachers in training of the Bachelor’s Degree in Teaching and Learning of Biology in Secondary Education of the Official Higher Normal School of Guanajuato, Mexico. The work is located within the paradigm of qualitative research and has a descriptive explanatory design. The results offer the bases to build, in a subsequent study, teaching actions and strategies that develop and enhance the creativity of students in training and, as a consequence, innovation and transformation of teaching practice in teaching and learning of sciences in basic education.La creatividad juega un papel fundamental en la educación. En todo el mundo, los institutos educativos están pidiendo a los docentes que implementen un cambio de la pedagogía tradicional para ser más creativos y aplicar la creatividad en sus actividades de enseñanza. Sin embargo, a menudo se piensa que los maestros no cuentan con los conocimientos y las capacidades necesarios, que son resistentes y lentos para cambiar. En este estudio se exploró la concepción de creatividad, la experiencia, reflexión e impacto en su práctica de 54 docentes en formación de la Licenciatura en Enseñanza y Aprendizaje de la Biología en la Educación Secundaria de la Escuela Normal Superior Oficial de Guanajuato, México. El trabajo se ubica dentro del paradigma de la investigación cualitativa y tiene diseño descriptivo explicativo. Los resultados ofrecen las bases para construir, en un estudio posterior, acciones y estrategias docentes que desarrollen y potencien la creatividad de los estudiantes en formación y, como consecuencia, la innovación y transformación de la práctica docente en la enseñanza y aprendizaje de las ciencias en la educación básica

Effect of aluminum precursor on physicochemical properties of Al2O3 by hydrolysis/precipitation method

Abstract This study reports the synthesis of mesoporous nano-fibrillar alumina prepared by hydrolysis-precipitation route. It was done from aqueous solution of aluminum sulfate analytical reagent (AR) and compared to aluminum sulfate technical grade (TG) of low purity under similar conditions using ammonia as the precipitating agent. The phisicochemical properties of these samples were studied with the assistance of characterization techniques such as Thermogravimetric and differential thermal analysis (TG/DTGA-DTA), X-ray diffraction (XRD), N2 adsorption-desorption isotherms, Fourier transform infrared (FTIR) spectroscopy, particles size and Transmission electron microscopy with energy-dispersive X-ray analysis (TEM/EDAX). The TG-DTA and XRD results show greater stability and a slightly greater crystallinity in Al2O3-TG sample than Al2O3-AR. N2 adsorption-desorption results show for both materials greatly surface area of 311 m2/g for Al2O3-TG and 272 m2/g for Al2O3-AR exhibiting characteristics of mesoporous materials. The FTIR results show a low percentage of surface OH groups for Al2O3-TG showing a lower acidity due to the low concentration of Al-OH species (AlIV). TEM measurements confirmed that fibers size ranged from 20 to 100 nm, for Al2O3-TG and 20-80 nm, and for Al2O3-AR. EDAX shows the presence of 0.33 % wt. of Mg as an impurity in Al2O3-TG. It is attributed that this amount is sufficient to generate structural defects and decrease acidity slightly. Likewise, it extended the fibrillar chain of the alumina.Resumen Este estudio reporta la síntesis de alúmina nano-fibrilar mesoporosa preparada por vía de hidrólisis-precipitación. Se realizó a partir de una solución acuosa de reactivo analítico (AR) de sulfato de aluminio y se comparó con un sulfato de aluminio grado técnico (TG) de baja pureza bajo condiciones similares usando amoníaco como agente precipitante. Las propiedades fisicoquímicas de estas muestras se estudiaron mediante diversas técnicas de caracterización, como el análisis térmico termogravimétrico y diferencial (TG/DTGA-DTA), difracción de rayos-X (DRX), Isotermas de adsorción-desorción N2, Espectroscopía infrarroja (FTIR), tamaño de partícula y Microscopia Electrónica de Transmisión con análisis de Energía Dispersiva de rayos-X (TEM/EDAX). Los resultados de TG-DTA y XRD muestran una mayor estabilidad y una cristalinidad ligeramente mayor en la muestra de Al2O3-TG que Al2O3-AR. Los resultados de adsorción-desorción de N2 muestran que ambos materiales tienen una alta área superficial de 311 m2/g para Al2O3-TG y 272 m2/g para Al2O3-AR exhibiendo características de materiales mesoporosos. Los resultados FTIR muestran un bajo porcentaje de grupos OH superficiales para Al2O3-TG, mostrando una acidez menor debido a la baja concentración de especies Al-OH (AlIV). Las mediciones de TEM confirmaron que el tamaño de las fibras varió de 20 a 100 nm para Al2O3-TG y 20-80 nm para Al2O3-AR. El análisis EDAX muestra la presencia de 0.33% peso de Mg como impureza en Al2O3-TG. Se atribuye que esta cantidad es suficiente para generar defectos estructurales y disminuir ligeramente la acidez. Además, extendió la cadena fibrilar de la alúmina de Al2O3-TG

Adsorption of Aqueous As (III) in Presence of Coexisting Ions by a Green Fe-Modified W Zeolite

The high toxicity of arsenite and the difficulty to remove it is one of the main challenges for water treatment. In the present work the surface of a low cost zeolite was modified by chemical treatment with a ferrous chloride to enhance its arsenite adsorption capacity. The effect of pH, ions coexistence, concentration, temperature and dosage was studied on the adsorption process. Additionally, the Fe-modified W zeolite was aged by an accelerated procedure and the regeneration of the exhausted zeolite was demonstrated. The Fe-modified W zeolite was stable in the pH range of 3 to 8 and no detriment to its arsenite removal capacity was observed in the presence of coexisting ions commonly found in underground water. The studies showed that the adsorption of As (III) on Fe-modified W zeolite is a feasible, spontaneous and endothermic process and it takes place by chemical bonding. The exhausting process proved the adsorption of 0.20 mg g&#8722;1 of As (III) by the Fe-modified W zeolite and this withstand at least five aging cycles without significant changes of its arsenite adsorption capacity. Fe-modified W zeolite prepared from fly ash might be a green and low-cost alternative for removal of As (III) from groundwater