Morfología, tamaño y distribución de partículas en semillas de cinco especies del género Opuntia

Las semillas del género Opuntia constituyen actualmente un desperdicio. Encontrar algún componente básico que permita su uso como complemento nutritivo en la elaboración de otro producto resultaría de interés socioeconómico. El objetivo fue evaluar la morfología y determinar el tamaño y la distribución de partículas que conforman las semillas de las siguientes especies: Opuntia heliabravoana Scheinvar, O. imbricata Haw, O. matudae Scheinvar, O. joconostle Haage y O. ficus indica Miller. Las semillas fueron molidas y la extracción de las partículas se realizó en suspensión con agua fría. Para valorar su morfología se realizaron observaciones al microscopio electrónico (MEB). El tamaño y distribución fueron medidos en un analizador de tamaño de partículas por difracción de rayos láser. Los tamaños de partículas variaron entre 23.81 y 55.13 µm. La variación y distribución de tamaños osciló desde 0.044 hasta 1 143 µm. El tamaño promedio de partículas de las cinco especies fue de 37.97 µm y por sus dimensiones se asemejan y aproximan a los tamaños promedios medidos en MEB. Los gránulos predominantes fueron de forma semiesférica y correspondieron a gránulos de almidones. La estimación de los tamaños promedios de partículas y morfologías resulta importante para asociar resultados obtenidos en evaluaciones histoquímicas previas, con los almidones contenidos en ellas

Low-Cost Energy-Autonomous Sensor Nodes Through RF Energy Harvesting and Printed Technology

The irruption of Internet of Things and 5G in our society comes along with several technological challenges to overcome. From an overall perspective, the low-cost and environmental friendliness of these technologies need to be ensured for their universal deployment in different areas, starting with the sensors and finishing with the power sources. To address these challenges, the production and maintenance of a great number of sensor nodes incur costs, which include manufacturing and integration in mass of elements and sub-blocks, changing or recharging of batteries, as well as management of natural resources and waste. In this article, we demonstrate how Radio Frequency Energy Harvesting (RFEH) and printed flexible technology (a growing technology for sensors) can solve these concerns through costeffective mass-production and utilization of energy harvesting for the development of energy-autonomous nodes, as part of a wireless sensor network. We present as illustration a sprayed flexible relative humidity sensor powered with RFEH under the store-and-use principle.This work was partially supported by the ECSEL Joint Undertaking through the Electronic Component Systems for European Leadership Joint Undertaking under grant agreement No 737434. This Joint Undertaking receives support from the German Federal Ministry of Education and Research and the European Union’s Horizon 2020 research and innovation program and Slovakia, Netherlands, Spain, Italy. In addition, the Spanish Ministry of Education, Culture and Sport (MECD) and the European Union supported it through the pre-doctoral grant FPU16/01451 and the fellowship H2020-MSCA-IF-2017794885-SELFSENS

Competence-based profile of undergraduate students in Madrid’s universities: Differences in terms of the gender and age

The aim of this study is to corroborate whether the development of academic excellence is affected by the gender and age of students. A sample of 364 students from different universities in the Community of Madrid were administered COMPEUEM, a test that assesses the extent to which students possess eight academic competencies: communication, leadership, team work, adaptation to the changes, initiative, problem solving, decision making, organization, and planning. All students took the test on site, in the classrooms of the participating universities. The results show that older subjects score higher in the acquisition of skills than younger ones. On the other hand, significant differences were found in function of the gender of the students. The authors conclude that having reliable tools to assess academic competencies may help design new teaching methodologies that better adapt to the students’ individual differences and the needs they will face when entering the labor market.-------Perfil competencial de los estudiantes de últimos cursos de grado en las universidades de la Comunidad de Madrid: Diferencias en función del género y la edadResumenEl objetivo de este estudio es comprobar si el desarrollo de las competencias académicas se ve afectado por el género y la edad de los estudiantes. Para alcanzar este objetivo, a una muestra de 364 estudiantes de diferentes Universidades de la Comunidad de Madrid se les aplicó COMPEUEM, un test que evalúa en qué medida los estudiantes poseen 8 competencias académicas: comunicación, liderazgo, trabajo en equipo, adaptación a los cambios, iniciativa, solución de problemas, toma de decisiones, organización y planificación. Todos los estudiantes realizaron la prueba de autoinforme de forma presencial, en las aulas de los distintos centros universitarios que participaron en el estudio. Los resultados encontrados ponen de manifiesto que los sujetos de más edad presentan mayores niveles en la adquisición de competencias que los de menor edad. Por otro lado, se encontraron diferencias significativas en función del género de los estudiantes. Los autores concluyen que este tipo de resultados permite plantear que establecer herramientas fiables de evaluación en competencias académicas ayudará a diseñar nuevas metodologías de enseñanza más adaptadas a las diferencias individuales de los estudiantes y a las necesidades que se encontraran cuando se incorporen al mercado laboral.DOI: 10.18870/hlrc.v5i2.225 PDF document contains both the original in Spanish and an English translation

ZnMn2O4 as a material for supercapacitors and its stability against the electrolyte

The electrolyte is an essential part of a supercapacitor, conditioning its performance. Thus, the specific capacitance measured for the supercapacitor electrode in the typical three-electrode arrangement of an electrochemical cell is sometimes not reflected in the supercapacitor. For this reason, ZnMn2O4 electrodes have been manufactured by spray pyrolysis on ITO/glass. The electrodes have been characterized electrochemically, and in symmetrical supercapacitors in which three types of electrolyte have been used, studying the effect of the electrolyte on the stability of the electrode and the capacity of the supercapacitorUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Modelo de conciencia para la sustentabilidad

Roughly, the conscience for sustainability unveils a process of civil self-management in the face of the absence or inefficiency of state management in terms of resource supply and quality of public services. In this sense, the present work set out to establish a model for the study of the phenomenon. Documentary work was done with a sample selection of sources indexed to national repositories, considering the year of publication and the keywords. Lines related to the extension of the model, as well as to the comparison between regions are confirmed to corroborate the findings reported in the literature.Grosso modo, la conciencia para la sustentabilidad devela un proceso de autogestión civil frente a la ausencia o ineficiencia de la gestión estatal en materia de abastecimiento de recursos y calidad de los servicios públicos. En ese tenor, el presente trabajo se propuso establecer un modelo para el estudio del fenómeno. Se realizó un trabajo documental con una selección muestral de fuentes indexadas a repositorios nacionales, considerando el año de publicación y las palabras claves. Se advierten líneas concernientes a la extensión del modelo, así como a la comparación entre regiones para corroborar los hallazgos reportados en la literatura

Analysis of the development of the forgetfulness curve within a program of training in Basic Life Support for students of the Degree of Medicine from de University of granada. Pilot study.

Objetivo: El objetivo del estudio es analizar la curva del olvido en el aprendizaje del Soporte Vital Básico en estudiantes de medicina de la Universidad de Granada. Material y métodos: Se trata de un estudio observacional, descriptivo transversal, que establece como población diana a los estudiantes de Grado de Medicina de la Universidad de Granada que cursan cuarto y quinto curso. Periodo de estudio comprendido entre octubre de 2015 y enero de 2017.Se emplearon los datos obtenidos en una evaluación inicial que se realizó en la Facultad de Medicina, y los de una reevaluación que se les realizó a una muestra de cada uno de los cursos. Se incluyeron en el estudio de forma voluntaria todos los alumnos matriculados en la asignatura bases de la medicina interna II para cada uno de los cursos académicos. El análisis se realizó utilizando medidas de tendencia central, tablas de frecuencias y posteriormente se realizó un análisis estadístico mediante la Prueba T de Student. Resultados: Los alumnos de cuarto consiguieron una media en la primera evaluación de 13,91 sobre 15 puntos, mientras que en la segunda la media fue de 13,81. Por otro lado, los alumnos de quinto consiguieron una media de 13,80 en la primera evaluación y una de 13,18 en la reevaluación. Estos datos nos hablan de que, a pesar de que los cursos resultaron muy satisfactorios en ambos cursos, encontramos un mayor impacto de la curva del olvido en alumnos que llevan más tiempo sin realizar un reciclaje en Soporte Vital Básico. Conclusiones: A pesar de existir una disminución de los conocimientos y habilidades relacionados con la práctica del soporte vital al año de recibir la formación específica en ambos grupos, no existen diferencias estadísticamente significativas para los sujetos de nuestro grupo que obliguen a establecer programas de reciclaje entre seis y nueve meses como establecen las recomendaciones actuales. A la luz de nuestro estudio, recomendamos el desarrollo de programas específicos de reciclaje en períodos de tiempo superiores a los doce meses después de recibir la formación inicial.Aim: The aim of this study was to analyze the oblivion curve after the learning of Basic Life Support (BLS) in medicine students from the University of Granada. Method: This was an observational, transversal descriptive study, which established as target population students from the Faculty of Medicine (University of Granada) who attended fourth and fifth year. The Study period comprised between October 2015 and January 2017. The data which was used was obtained in an initial evaluation that was done at the Faculty of Medicine and in a re-evaluation which was applied to a selected sample of students from each year. All the students included voluntarily in the study were enrolled in the subject Internal Medicine II. The analysis was carried out using measures of central tendency, frequency tables and after that, a statistical analysis using the Student´s T-test. Results: Fourth year students obtained an average in the first evaluation of 13,91 over 15 points, while in the second evaluation it was 13,81. Meanwhile, fifth year students achieved an average of 13,80 in the first evaluation and of 13,18 in the re-evaluation. This data speak of very satisfactory results for students in both years, although the impact of the oblivion curve is higher in students who have spent more time without taking a recycling course of BLS. Conclusions:.Even though there is a decrease of knowledge and abilities related to the practice of basic life support a year after receiving the specific training in both groups, there are not differences statistically significant for the subjects of our group that would make us establish recycling programs after six or nine months, as advice the actual recommendations. 2.Based on the results we obtained, we would recommend the development of specific recycling programs in periods of time bigger than twelve months after receiving the initial training

Prevalence of Metabolic Syndrome Components in an Urban Mexican Sample: Comparison between Two Classifications

Background. The aim of this study was to examine the prevalence of metabolic syndrome (MS) components in an urban Mexican sample. Methods. A total of 854 subjects were included. Anthropometric, blood pressure measurements, clinical data, and overnight fasting blood samples were obtained from all subjects. Results. In accordance with definitions by the American Heart Association/ National Heart, Lung, and Blood Institute (AHA/NHLBI) and the International Diabetes Federation (IDF), the prevalence of MS among participants was 59.7 and 68.7%, respectively. The prevalence of MS was higher in women and in individuals older than 45 years of age. More than 40% of the subjects fulfilled four criterions of MS according to both definitions. Conclusions. There was a high prevalence of MS components in an urban Mexican sample. Therefore, strong strategies had to be developed for early detection of MS and its components to prevent DMT2 and atherothrombotic complications in these patients

Towards airborne laser-induced breakdown spectroscopy: A signal recovery method for LIBS instruments subjected to vibrations

Sample or instrument vibrations can scatter laser impacts across the sample surface, which increases the uncertainty of laser-induced breakdown spectroscopy (LIBS) measurements. The common sources of noise associated to mechanical vibration are described and a method for isolating LIBS measurements from artifacts introduced by such fluctuations is presented. The approach circumvents the use of mechanical stabilizers by leveraging simple components common in LIBS systems. A camera was used to capture close-up images of the sample for each laser shot and the laser spot position in the sample surface was measured using common image processing techniques. By associating spectra with spatial coordinates in the sample surface, it was possible to reduce the relative standard deviation of the Cu(I) 427.51 nm signal in a patterned Cu/Al sample from 122.0% to 53.31%, similar to that measured for a pure Cu sample in the same vibration conditions. The spatial resolution of the method was found to depend on the laser spot diameter, the illuminance at the sample, the camera sensitivity and trigger insertion delay, and the speed of the laser beam sweeping the sample surface. The spatial resolution obtained with the setup used was ±0.6 mm at 15 m, i.e., 40 μm per meter of separation between the instrument and the sample with a vibration speed limit of 12 cm·s−1.The authors would like to express their gratitude to Carlos Malagon ´of Astroshop (Málaga, Spain) for donating the telescope used in the stand-off LIBS instrument. This work has been partially supported by the Programa Estatal para la Incorporacion ´ Estable de Doctores (IEDI-2017-00828) and by the I Plan Propio de Investigacion ´ de la Universidad de Malaga ´ (Spain). Funding for open access charge: Universidad de Malaga/CBUA