4,008 research outputs found
On the Entropy of Oscillator-Based True Random Number Generators under Ionizing Radiation
The effects of ionizing radiation on field-programmable gate arrays (FPGAs) have been
investigated in depth during the last decades. The impact of these effects is typically evaluated on
implementations which have a deterministic behavior. In this article, two well-known true-random
number generators (TRNGs) based on sampling jittery signals have been exposed to a Co-60 radiation
source as in the standard tests for space conditions. The effects of the accumulated dose on these
TRNGs, an in particular, its repercussion over their randomness quality (e.g., entropy or linear
complexity), have been evaluated by using two National Institute of Standards and Technology
(NIST) statistical test suites. The obtained results clearly show how the degradation of the statistical
properties of these TRNGs increases with the accumulated dose. It is also notable that the deterioration
of the TRNG (non-deterministic component) appears before that the degradation of the deterministic
elements in the FPGA, which compromises the integrated circuit lifetime.Ministerio de Economía y Competitividad (ESP-2015-68245-C4-1-P)Ministerio de Economía y Competitividad (ESP-2015-68245-C4-4-P)Ministerio de Economía y Empresa (TIN2016-79095-C2-2-R)CAM (S2013/ICE-3095
Compounding process optimization for recycled materials using machine learning algorithms
The sustainable manufacturing of goods is one of the factors to minimize natural resource depletion and CO2 emissions. In the last decade a big effort has been done to transition from linear economy to circular economy. This transition requires to implement re-manufacturing processes into the current industrial manufacturing framework, replacing the sourcing of raw materials by re-manufacturing technologies. However, this transition is very challenging since it requires the transformation of the companies and more specially their processes, from traditional to circular. To speed up this transformation, the use of tools provided by the 4th industrial revolution are crucial. In particular, the use of artificial intelligence techniques enables the optimization of the re-manufacturing processes and make those optimizations available to all the stakeholders. This paper presents an optimization system for re-manufacturing of recycled fiber through compounding processes with materials that come from composite waste or end of life of products. The proposed approach has been trained with the data collected from several experiments carried out with a compounding machine under different specifications, fiber reinforcement grades, and output material properties. The system will allow to set up a compounding machine for different types of reinforced plastics needless of setting point experiments. The algorithms have been tested with previously unseen scenarios and they have proved to be efficient for giving the optimal material characteristics.This work has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 873111 (DIGIPRIME)
Incidence and prevalence of multiple sclerosis in Spain: a systematic review
[EN] Introduction: Greater understanding of the prevalence and incidence of multiple sclerosis in Spain and their temporal trends is necessary to improve the allocation of healthcare resources and to study aetiological factors. Methods: We performed a systematic search of the MedLine database and reviewed the reference lists of the articles gathered. We collected studies reporting prevalence or incidence rates of multiple sclerosis in any geographical location in Spain, with no time limits. In 70% of cases, data were extracted by 2 researchers (FGL and EAC); any discrepancies were resolved by consensus. Results: We identified 51 prevalence and 33 incidence studies published between 1968 and 2018. In the adjusted analysis, the number of prevalent cases per 100 000 population increased by 26.6 (95% confidence interval [CI], 21.5-31.8) every 10 years. After adjusting for year and latitude, the number of incident cases per 100 000 population increased by 1.34 (95% CI, 0.98-1.69) every 10 years. We observed a trend toward higher prevalence and incidence rates at higher latitudes. Conclusions: The prevalence of multiple sclerosis in Spain has increased in recent decades, although case ascertainment appears to be incomplete in many studies. Incidence rates have also increased, but this may be due to recent improvements in the detection of new cases. [ES] Introducción: El conocimiento de la prevalencia y de la incidencia de la esclerosis múltiple en España y de sus tendencias temporales es necesario para planificar mejor los servicios clínicos y estudiar factores etiológicos. Método: Se efectuó una revisión sistemática, mediante una búsqueda en Medline y en las referencias de cada artículo, de todos los estudios que describieran cifras de prevalencia o de incidencia de la esclerosis múltiple en algún lugar geográfico de España, sin límites temporales. En el 70% de los casos la extracción de datos la hicieron dos observadores (FGL y EAC), que resolvieron las discrepancias por consenso. Resultados: Se identificaron 51 estudios de prevalencia y 33 de incidencia entre 1968 y 2018. En el análisis ajustado, por cada 10 años la prevalencia por 100 000 habitantes aumentó en 26,6 (intervalo de confianza -IC- del 95%, 21,5 a 31,8). Según los datos del análisis ajustado por el año y la latitud, por cada 10 años la incidencia por 100 000 habitantes aumentó en 1,34 (IC 95%, 0,98 a 1,69). Se observó una tendencia de mayores prevalencias e incidencias en latitudes más altas. Conclusiones: La prevalencia de la esclerosis múltiple aumentó en las últimas décadas en España, aunque en muchos estudios la verificación de casos parece haber sido incompleta. La incidencia también aumentó, pero eso puede deberse a una detección de casos nuevos más exhaustiva en los últimos años.This study has received funding from Biogen Idec, S. L.S
Ultrasonic radiation influence on the bioadsorbent characteristics of citrus (citrus x lemon) & (citrus x sinensis)
Of all the materials used as adsorbents, activated charcoal is the most popular as it is excellent for reducing/eliminating a wide variety of contaminants. This capacity is mainly due to its structural characteristics that give it a large surface area. However, it has several disadvantages. The most important are that the adsorbent material is quite expensive as is its regeneration. For this reason, more economical absorbents have been sought, highlighting the study of adsorption phenomena in some types of biomass as adsorbents. Bioadsorption is considered a viable alternative to the physical-chemical methods currently used for the recovery or removal of heavy metals dissolved in liquid effluents. Its main attraction, from an industrial point of view, is its low cost due to the great abundance, easy to obtain and low price of the bioadsorbent material. Bioadsorption is very effective in treating metal concentrations below 100 mg/L, where the application of physical-chemical methods is neither technically nor economically feasible. One of these materials of interest is citrus peels, because, due to their abundance as a waste product of the food industries, they are hardly reused and currently have little economic value. However, these residues have a low adsorption capacity, so both physical and chemical modifications are required to increase their adsorption properties. This study compares the characteristics of orange and lemon peels undergoing a physical-chemical treatment with ultrasonic radiation assistance and the optimization of experimental conditions to obtain useful bioadsorbents in discontinuous processes (batch)Postprint (published version
Medición de los niveles de actividad física en personas con discapacidad física mediante acelerometría y cuestionario
Objetivo:
Analizar la relación entre el nivel de actividad física registrada y el percibido en población con discapacidad física mediante acelerometría y cuestionario, así como estudiar las diferencias evaluadas con ambos instrumentos según nivel de actividad física personal y otras variables como el género o uso de la silla de ruedas.
Metodología:
La muestra la componen 37 sujetos con discapacidad física (28 hombres y 9 mujeres), con una edad media de 38 ±10,9 años. Se dividió a la muestra en tres grupos en función del número de horas de actividad física semanal: sedentarios (S, n = 8), practicantes habituales (PH, n = 13) y practicantes de alto rendimiento (AR, n = 16). Los sujetos llevaron un monitor metabólico de actividad física SenseWear Pro Armband (SWA) durante siete días, las 24 horas. Una vez retirado, se administró el cuestionario Physical Activity Scale for Individuals with Physical Disabilities (Escala de Actividad Física para Personas con Discapacidades Físicas) para medir la actividad física percibida, recogiéndose también datos antropo-métricos y personales.
Resultados:
La correlación de Pearson (n = 37) mostró relación entre el PASIPD y las variables METS promedio (r=0,52; p<0,01), gasto energético en activo (r=0,35; p<0,05) y duración de la actividad física (r=0,53; p<0,01). El PASIPD (en MET hr/día) arrojó los siguientes valores según grupo: S 8,55 ±4,35; PH 12,99 ±5,88; AR 27,41 ±19,66. Según grupos, el SWA registró, entre otras variables, los METs promedio (S 1,35 ±0,26; PH 1,46 ±0,19; AR 1,70 ±0,18) y la duración de la actividad física (S 10:33:07 ±07:47:42; PH 12:59:32 ±07:21:38; AR 22:22:26 ±07:58:58). El ANOVA mostró diferencias (p<0,05) entre grupos para el PASIPD y las citadas variables del SWA.
Conclusiones:
Este estudio confirma la idoneidad de utilizar de forma combinada un cuestionario y un monitor metabólico
de actividad física en población con discapacidad física para la evaluación del nivel de actividad física en esta població
Patrimonio natural y cultural de Tepotzotlán
324 páginas. Especialización en Diseño, Planificación y Conservación de Paisajes y Jardines.El presente documento muestra el trabajo realizado para la intervención paisajística en pueblo de Tepotzotlán. Al ser catalogado en el programa de pueblos mágicos dada su riqueza tangible e intangible; resulta relevante su estudio a fin de rescatar y/o enaltecer algunas de las virtudes que lo resguardan. La zona de intervención se enfocó esencialmente en el polígono patrimonial del centro histórico, los caminos constituidos a lo largo de Rio Chiquito y calles aledañas que conectan los tesoros patrimoniales de la zona. Dicho estudio fue abordado principalmente por grupos de trabajo interdisciplinario, conformados por alumnos de la especialidad en Paisajes y Jardines Históricos de la UAM Azcapotzalco. Se cotejaron 5 proyectos detonadores: Centro Histórico/Atrio de los Olivos, Par vial, Rio Chiquito, Camino Real de Lluvias y Acequia Real. Durante la primera etapa, se establecieron las limitaciones y potencialidades del sitio. Se recopiló información cualitativa y cuantitativa para la formulación y ejecución de un plan maestro que regirían los parámetros y objetivos en cada proyecto. El desarrollo conceptual y anteproyecto para cada zona de intervención, se reflejó en la segunda etapa de este proceso. Paralelamente, la elaboración de la propuesta de vegetación, las fichas de cada especie vegetal y la preparación de catálogos de paisaje, complementan el carácter de este trabajo. El proyecto realizado en Tepotzotlán: “Patrimonio Natural y Cultural De Tepotzotlán”, emerge, como el título del trabajo indica: desde la visión del rescate patrimonial, constituido por elementos materiales y naturales relevantes para la población local y todos sus visitantes. La última etapa comprende la puesta en marcha del proyecto ejecutivo, donde se plasmaron los detalles que dan cuerpo a cada elemento de las propuestas de diseño, la información necesaria para su construcción y la síntesis de toda la documentación consultada y elaborada, como sostén de diseño. En las siguientes páginas y capítulos, se explicará de manera extensa y particular: la metodología planteada y utilizada en el abordaje de cada proyecto. En general, se podrá observar la construcción de un trabajo paisajístico integral, llevado a cabo a lo largo de un año de esfuerzo y dedicación, vertidos en la presente tesis.Consejo Nacional de Ciencia y Tecnología (México)
Effective degradation of cyclohexanecarboxylic acid by visible LED driven photo-Fenton
This work explores the feasibility of visible LEDs (λ: 400–800 nm) used in photo-Fenton for the degradation of a 50 mg/L cyclohexanecarboxylic acid (CHA) as model naphthenic acid present in process wastewater from the oil sands industry. The influence of initial pH, catalyst concentration and iron oxidation state, H2O2 dose and radiant flux were studied. In all trials, an initial lag phase in both the H2O2 decomposition and TOC evolution was observed. This seems to be related to the generation of a complex between CHA, hydrogen peroxide and iron (CHA-H2O2-Fe). This iron scavenging decreases the H2O2 decomposition rate, leading to a lagged mineralization kinetics. Nonetheless, process intensification using visible radiation (λmax: 460 nm) favors the CHA-H2O2-Fe photoactivation and breakdown when using an H2O2 concentration higher than 33% of the stoichiometric dose for complete CHA mineralization. Under the optimum conditions pH0 3, Φ: 280 W/m2, Fe2+:20 mg/L and H2O2: 144 mg/L, which corresponds to 60% of the stoichiometric amount, 75% of TOC removal was achieve
Conocimiento del personal de enfermería sobre la técnica de aspiración de secreciones por tubo endotraqueal en unidades hospitalaria
The objective of this work was to conduct a systematic review on the knowledge and practice of endotracheal suctioning technique among nursing staff in hospital units. 10 review articles and 8 original articles from different databases such as Scopus, Scielo, and Latindex were selected. It was found that knowledge and practice of suctioning technique varied significantly among nursing staff in different hospital units and countries. Studies identified a lack of proper knowledge and skills in the suctioning technique, as well as the need for training and continuous education. Practical implications include the importance of improving nursing staff's training and education to enhance patient care and safety. Future challenges include the need for standardization and continuous updating of suctioning protocols and the need for further research to evaluate the effects of suctioning technique on critically ill patients. Possible limitations of this study include limited database selection and lack of access to all relevant articles. In conclusion, this work highlights the need to improve nursing staff's education and continuous training in the suctioning technique to ensure quality and safe patient care.El objetivo de este trabajo fue realizar una revisión sistemática sobre el conocimiento y la práctica de la técnica de aspiración de secreciones por tubo endotraqueal en personal de enfermería en unidades hospitalarias. Se seleccionaron 10 artículos de revisión y 8 artículos originales de diferentes bases de datos como Scopus, Scielo y Latindex. Se encontró que el conocimiento y la práctica de la técnica de aspiración de secreciones varían significativamente entre el personal de enfermería en diferentes unidades hospitalarias y países. Los estudios identificaron una falta de conocimiento y habilidades adecuadas en la técnica de aspiración, así como la necesidad de capacitación y educación continua. Las implicancias prácticas incluyen la importancia de mejorar la capacitación y la formación del personal de enfermería para mejorar la atención y seguridad del paciente. Los desafíos futuros incluyen la necesidad de una estandarización y actualización continua de los protocolos de aspiración y la necesidad de investigaciones adicionales para evaluar los efectos de la técnica de aspiración en pacientes críticos. Las posibles limitaciones de este estudio incluyen la selección limitada de bases de datos y la falta de acceso a todos los artículos relevantes. En conclusión, este trabajo destaca la necesidad de mejorar la educación y la formación continua del personal de enfermería en la técnica de aspiración de secreciones para garantizar una atención de calidad y segura para los pacientes
Increasing efficiency and reducing bias in the sampling of seed-dispersal interactions based on mist-netted birds
Efficient and unbiased sampling of ecological interactions is essential to our understanding of the functions they mediate. Seed dispersal by frugivorous birds is a key mutualism for plant regeneration and community dynamics. Mist-netting is one of the most widely used methods to sample avian seed dispersal through the identification of seeds in droppings of captured birds kept inside cloth bags. However, birds may drop seeds on the ground before being extracted from the net, leading to a fraction of missing information due to ineffective sampling. Worryingly, this fraction could be unevenly distributed across bird and plant species, leading to sampling biases. Here, we assess the effectiveness of using a 1-m wide mesh below mist nets to sample seeds dropped by entangled birds. We used data from birds mist-netted during one-year-round. We sampled nearly 50% of interaction events and 75% of dispersed seeds on the mesh band below the mist nets (i.e. lost information without this optimization). The proportion of seeds sampled on the mesh bands was not evenly distributed among bird species but strongly related to bird size, ranging from 57–63% in warblers to 84–94% in thrushes. Moreover, the proportion of seeds sampled on the mesh was negatively related to seed size, although this relationship was weaker. We also evaluated accumulation curves of species and pairwise interactions with increasing sampling effort, both with and without using the mesh bands. The number of seed species sampled increased by 21% when using the mesh bands and the number of pairwise interactions by 36%. Our findings provide strong evidence on how inefficient and biased traditional mist-netting can be for sampling community-wide seed–dispersal interactions. We thus urge the use of mesh bands in future studies to increase sampling effectiveness and avoid biases, which will ultimately improve our understanding of the seed dispersal function
Photocatalytic activation of peroxymonosulfate using ilmenite (FeTiO3) for Enterococcus faecalis inactivation
In this work, a raw and low cost mineral, ilmenite (FeTiO3), has been tested for the first time as a photocatalyst paired with peroxymonosulfate (HSO5-; PMS) for the inactivation of Enterococcus faecalis as an alternative to conventional treatments to disinfect wastewater for reuse. The influence of some operational parameters such as reagent dosage, catalyst concentration, initial pH, or flow rate was also studied and optimized. After several tests, the scarce pure photoactivity under UV-A was remarked by ilmenite because of its high iron content, which favors photogenerated charge recombination. However, ilmenite activity was highly promoted when combined with low concentrations of PMS and UV-A light, reaching total inactivation of Enterococcus faecalis in 120 min. Quenching tests were performed using methanol, tert-butyl alcohol, furfuryl alcohol, and Cu(II) to assess the main reactive species involved in the disinfection process determining the critical role of both HO·and SO4·- radicals in the process. Finally, the influence of the water matrix was also evaluated by studying the effect of water hardness and the presence of nutrients on the system. Overall, the PMS/Ilmenite/UV-A system yielded promising results with a total removal of Enterococcus faecalis in 120 min. However, it also showed the need for further study and understanding of the disinfection mechanism to achieve the same level of performance in real wastewaterPGM acknowledges Escuela Técnica Superior de Ingenieros Industriales (UPM) for the project ETSII-UPM20–03. SGR acknowledges UPM for the predoctoral contract granted within the ’Programa Propio’. JRC acknowledges Comunidad de Madrid for funding the research project IN_REUSE (APOYO-JOVENES-X5PKL6–88-KZ46KU), and also by the pluriannual agreement with the Polytechnic University of Madrid in the line of action Programme of Excellence for University Teaching Staf
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