85 research outputs found

    Procesadores de bajo coste y su aplicación en la docencia de Ingeniería de Computadores

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    La Informática evoluciona a gran velocidad y es necesario actualizar con frecuencia los recursos de aprendizaje para mantener el interés de los estudiantes. En la actualidad, hay una gran diversidad de plataformas de cómputo de bajo coste que son utilizadas como recursos en los estudios de Informática. Raspberry Pi y algunos modelos de Arduino (como Arduino Due), ambas basadas en procesadores ARM, son ejemplos representativos de este tipo de plataformas. Las arquitecturas ARM son ejemplos de procesadores RISC que actualmente gozan de gran popularidad por su buena relación entre potencia computacional, consumo y coste. De hecho, constituyen el núcleo de muchos de los teléfonos móviles y sistemas empotrados actuales. Al estar tan cerca de los estudiantes, el uso de este tipo de recursos en el aula representa una oportunidad para: (1) motivar a los alumnos de Bachillerato y Educación Secundaria para estudiar el Grado de Informática y (2) potenciar el interés de los alumnos de Grado de Informática por la Ingeniería de Computadores. Existe una serie de eventos consolidados que tienen una gran difusión social. En ellos, se muestran vistosos ejemplos de aplicación y funcionamiento de este tipo de plataformas. En este trabajo se describen el conjunto de sistemas interactivos y basados en plataformas computacionales de bajo coste que se han desarrollado para ser utilizadas en este tipo de eventos. De acuerdo con nuestra experiencia de participación, creemos que están sirviendo para despertar el interés del alumno de secundaria por la Informática en general, y más específicamente por la Ingeniería de Computadores. Por otra parte, un porcentaje de los alumnos que cursan el Grado de Ingeniería Informática no está interesado en el análisis de los componentes hardware y de su organización para construir un computador moderno. Piensan que la asignatura de Arquitectura de Computadores del Grado en Ingeniería Informática está lejos de su futura actividad profesional. En este contexto, nos planteamos seleccionar ARM como arquitectura de referencia para desarrollar los contenidos de la asignatura de Arquitectura de Computadores. Creemos que esta decisión mejora el interés del alumno por dos motivos: (1) el objeto de estudio se usa en multitud de plataformas muy cotidianas para el alumno y (2) es posible diseñar las actividades prácticas de las asignaturas basadas en elementos reales y no únicamente virtuales. Este trabajo muestra las distintas actividades tanto a nivel teórico como práctico que se plantean al alumno en el marco de la asignatura Arquitectura de Computadores.Computer Science is advancing rapidly and it is necessary to keep the educational resources up to date in order to keep the interest of students. Nowadays, there is a wide variety of low-cost computing platforms that are used as educational resources in the Computer Science degree. Raspberry Pi and some models of Arduino (such as Arduino Due), which are both based on ARM processors, are representative examples of this kind of platforms. ARM architectures are instances of RISC processors which nowadays have reached an important popularity due to their good relation between performance, consumption and cost. In fact, they constitute the core of numerous current mobile phones and embedded systems. Considering their proximity to the students, the use of this kind of resources in the classroom is an opportunity to: (1) encourage the high schools pupils to study the Computer Science degree and (2) to increase the interest of the students for the Computer Engineering. There are several consolidated informational events of great social outreach in which different examples of application of this kind of platforms are shown. In this work, the set of interactive systems designed to be used in this kind of events is described. According to our experience, we think that they arouse the interest of high schools pupils for the Computer Science in general, and, more specifically, for the Computer Engineering. Furthermore, a percentage of the students of the Computer Science degree is not interested in the analysis of hardware components and the architecture of modern computers. They think that the subject of Computer Architecture of the Computer Science Degree is far from his/her future career. In this context, we will select ARM as a reference architecture where the contents of the subject Computer Architecture will be developed on. We think this might improve the motivation of the students mainly for two reasons: (1) the object of study is being used in a lot of modern platforms; and (2) it is possible to design the practical activities of the subjects using real platforms and not only virtual ones. This work shows the activities proposed to the students in the context of the subject Computer Architecture, considering both practical and theoretical approaches

    Comparative Genome Analysis of Bifidobacterium longum subsp. infantis Strains Reveals Variation in Human Milk Oligosaccharide Utilization Genes among Commercial Probiotics

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    Dysbiosis is associated with acute and long-term consequences for neonates. Probiotics can be effective in limiting the growth of bacteria associated with dysbiosis and promoting the healthy development of the infant microbiome. Given its adaptation to the infant gut, and promising data from animal and in vitro models, Bifidobacterium longum subsp. infantis is an attractive candidate for use in infant probiotics. However, strain-level differences in the ability of commercialized strains to utilize human milk oligosaccharides (HMOs) may have implications in the performance of strains in the infant gut. In this study, we characterized twelve B. infantis probiotic strains and identified two main variants in one of the HMO utilization gene clusters. Some strains possessed the full repertoire of HMO utilization genes (H5-positive strains), while H5-negative strains lack an ABC-type transporter known to bind core HMO structures. H5-positive strains achieved significantly superior growth on lacto-N-tetraose and lacto-N-neotetraose. In vitro, H5-positive strains had a significant fitness advantage over H5-negative strains, which was also observed in vivo in breastfed infants. This work provides evidence of the functional implications of genetic dierences among B. infantis strains and highlights that genotype and HMO utilization phenotype should be considered when selecting a strain for probiotic use in infants

    Reduction of the Three Dimensional Schrodinger Equation for Multilayered Films

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    In this paper, we present a method for reducing the three dimensional Schrodinger equation to study confined metallic states, such as quantum well states, in a multilayer film geometry. While discussing some approximations that are employed when dealing with the three dimensionality of the problem, we derive a one dimensional equation suitable for studying such states using an envelope function approach. Some applications to the Cu/Co multilayer system with regard to spin tunneling/rotations and angle resolved photoemission are discussed.Comment: 14 pages, 1 figur

    The Atapuerca sites and the Ibeas hominids

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    The Atapuerca railway Trench and Ibeas sites near Burgos, Spain, are cave fillings that include a series of deposits ranging from below the Matuyama/Bruhnes reversal up to the end of Middle Pleistocene. The lowest fossil-bearing bed in the Trench contains an assemblage of large and small Mammals including Mimomys savini, Pitymys gregaloides, Pliomys episcopalis, Crocuta crocuta, Dama sp. and Megacerini; the uppermost assemblage includes Canis lupus, Lynx spelaea, Panthera (Leo) fossilis, Felis sylvestris, Equus caballus steinheimensis, E.c. germanicus, Pitymys subtenaneus, Microtus arvalis agrestis, Pliomys lenki, and also Panthera toscana, Dicerorhinus bemitoechus, Bison schoetensacki, which are equally present in the lowest level. The biostratigraphic correlation and dates of the sites are briefly discussed, as are the paleoclimatic interpretation of the Trench sequences. Stone artifacts are found in several layers; the earliest occurrences correspond to the upper beds containing Mimomys savini. A set of preserved human occupation floors has been excavated in the top fossil-bearing beds. The stone-tool assemblages of the upper levels are of upper-medial Acheulean to Charentian tradition. The rich bone breccia SH, in the Cueva Mayor-Cueva del Silo, Ibeas de Juarros, is a derived deposit, due to a mud flow that dispersed and carried the skeletons of many carnivores and humans. The taxa represented are: Vrsus deningeri (largely dominant), Panthera (Leo) fossilis, Vulpes vulpes, Homo sapiens var. Several traits of both mandibular and cranial remains are summarized. Preliminary attempts at dating suggest that the Ibeas fossil man is older than the Last Interglacial, or oxygen-isotope stage 5

    RICORS2040 : The need for collaborative research in chronic kidney disease

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    Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true

    Evolution of the use of corticosteroids for the treatment of hospitalised COVID-19 patients in Spain between March and November 2020: SEMI-COVID national registry

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    Objectives: Since the results of the RECOVERY trial, WHO recommendations about the use of corticosteroids (CTs) in COVID-19 have changed. The aim of the study is to analyse the evolutive use of CTs in Spain during the pandemic to assess the potential influence of new recommendations. Material and methods: A retrospective, descriptive, and observational study was conducted on adults hospitalised due to COVID-19 in Spain who were included in the SEMI-COVID- 19 Registry from March to November 2020. Results: CTs were used in 6053 (36.21%) of the included patients. The patients were older (mean (SD)) (69.6 (14.6) vs. 66.0 (16.8) years; p < 0.001), with hypertension (57.0% vs. 47.7%; p < 0.001), obesity (26.4% vs. 19.3%; p < 0.0001), and multimorbidity prevalence (20.6% vs. 16.1%; p < 0.001). These patients had higher values (mean (95% CI)) of C-reactive protein (CRP) (86 (32.7-160) vs. 49.3 (16-109) mg/dL; p < 0.001), ferritin (791 (393-1534) vs. 470 (236- 996) µg/dL; p < 0.001), D dimer (750 (430-1400) vs. 617 (345-1180) µg/dL; p < 0.001), and lower Sp02/Fi02 (266 (91.1) vs. 301 (101); p < 0.001). Since June 2020, there was an increment in the use of CTs (March vs. September; p < 0.001). Overall, 20% did not receive steroids, and 40% received less than 200 mg accumulated prednisone equivalent dose (APED). Severe patients are treated with higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%. Conclusions: Patients with greater comorbidity, severity, and inflammatory markers were those treated with CTs. In severe patients, there is a trend towards the use of higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%

    New insights into the genetic etiology of Alzheimer's disease and related dementias.

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    Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele
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