84 research outputs found
El salario mínimo en Colombia 2001-2006: efectos sobre la distribución de salarios por género
Este trabajo estima los efectos de incrementos del salario mínimo sobre hombres y mujeres para diferentes percentiles de la distribución en Colombia -- El análisis se realiza empleando el método de regresión RIF y la descomposición de Oaxaca-Blinder para el periodo 2001-2006 -- Se encontró que en mercados con una mayor incidencia del salario mínimo (SM)-medido por el número de trabajadores que son afectados en el margen por un incremento del SM-, el incremento en los salarios es mayor para hombres que para mujeres, especialmente en percentiles bajos, contribuyendo de forma significativa a la brecha salarial por géner
Phosphorus-Functionalized Graphene for Lithium-Ion Capacitors with Improved Power and Cyclability
Herein, we report an easy approach for the preparation of graphene-based materials suitable as electrodes for lithium-ion capacitors (LICs). To the best of our knowledge, this is the first time that phosphorus-functionalized graphene oxide (rGO800-P) is used as negative (battery-type) electrode in LICs technology. An activated carbon derived from the pyrolysis of graphene-carbon composite served as positive (capacitor-type) electrode. While phosphorus functionalization on the negative electrode enables fast Li+ kinetics during insertion/extraction processes, the flat-shaped morphology, large surface area and proper pore size distribution of the positive electrode enhance the double-layer formation. Full LICs optimization, oversizing the negative electrode allows operating in the extended voltage window of 1.5-4.5 V delivering high energy and power values (91 Wh kg(AM)(-1) at 145 W kg(AM)(-1) and 33 Wh kg(AM)(-1) at 26,000 W kg(AM)(-1)) without compromising the cycling performance (76 % capacitance retention after 10,000 cycles)The authors thank the European Union (Graphene Flagship, Core 3, Grant number 881603) and the Spanish Ministry of Science and Innovation (MICINN/FEDER) (RTI2018-096199-B-I00) for the financial support of this work. J.L.G.U. is very thankful to the Spanish Ministry of Education, Science and Universities (MICINN) for the FPU grant (16/03498). We also want to acknowledge the company GRAPHENEA for supplying the graphene oxide used in this wor
Procesos no lineales en la ciencia y la sociedad
La existencia de ondas ocurre como una de las formas de manifiestación del movimiento más común en el mundo que nos rodea. Aunque las ondas lineales juegan un papel crucial en el desarrollo de la ciencia en primera aproximación, las ondas de índole no lineal se consideran como las más “realistas” para describir procesos complejos. Una gran posibilidad para el desarrollo de teoría de ondas no lineales se abrió debido a la investigación de solitones, ondas que no cambian de forma y de energía a lo largo de su desplazamiento. En este contexto, en el capítulo de Tatyana Belyaeva y Vladimir Serkin se estudia el efecto túnel cuántico usando ondas no lineales solitónicas de óptica y ondas de materia. Como es conocido, la ecuación diferencial que gobierna estos pulsos ópticos es de la familia de ecuaciones no lineales de Schrödinger, por su analogía con la famosa ecuación de la mecánica cuántica.La evolución de la sociedad en gran medida está soportada por el avance del desarrollo científico. Por ende, la aplicación de conocimientos obtenidos en esfuerzos indagatorios sobre fenómenos que ocurren en el universo es una de las premisas sobre la cual se basa todo desarrollo tecnológico y científico de la humanidad. La investigación en torno a las diferentes manifestaciones de la naturaleza conduce al análisis de entidades interactuantes que condicionan el comportamiento a posteriori de los elementos que la conforman. Es así que el estudio de sistemas interactuantes constituye un tema central en cualquier disciplina científica. Sin embargo, el análisis matemático de estos sistemas no es un problema fácil, de hecho, el estado actual del conocimiento científico y matemático dista aún mucho de comprender a detalle todos los posibles comportamientos de los sistemas complejos. El problema radica principalmente en dos factores: el primero se refiere a la gran cantidad de componentes, variables y parámetros que pueden estar interactuando, lo que obliga a analizar simplificaciones del problema; y el segundo concierne a que las interacciones generalmente no son lineales. Una de las diferencias fundamentales entre procesos lineales y no lineales es que en estos últimos no se cumple el principio de superposición. Cuando el vasto número de procesos naturales no lineales se estudia, comúnmente se modela mediante sistemas de ecuaciones no lineales. Suele ocurrir frecuentemente que la complejidad de fenómenos que ocurren en la naturaleza y sociedad en muchos aspectos es descrita y analizada incluso bajo una misma ecuación diferencial no lineal, incluyendo también en muchos casos la influencia aleatoria de otros agentes externos, por lo que la estocasticidad estará presente de una u otra manera. Esto crea un cuadro relativamente exitoso en vista de que las investigaciones de procesos que ocurren se pueden llevar a cabo en forma aislada, analizarlas abstractamente en el mundo de las matemáticas, para luego volcar todo el arsenal de conocimientos en las respectivas áreas de interés que se realizan
Characterization of Tajogaite volcanic plumes detected over the Iberian Peninsula from a set of satellite and ground-based remote sensing instrumentation
Three volcanic plumes were detected during the Tajogaite volcano eruptive activity (Canary Islands, Spain,
September–December 2021) over the Iberian Peninsula. The spatiotemporal evolution of these events is characterised by combining passive satellite remote sensing and ground-based lidar and sun-photometer systems. The
inversion algorithm GRASP is used with a suite of ground-based remote sensing instruments such as lidar/
ceilometer and sun-photometer from eight sites at different locations throughout the Iberian Peninsula. Satellite
observations showed that the volcanic ash plumes remained nearby the Canary Islands covering a mean area of
120 ± 202 km2 during the whole period of eruptive activity and that sulphur dioxide plumes reached the Iberian
Peninsula
Diet quality index as a predictor of treatment efficacy in overweight and obese adolescents: The EVASYON study
Background & aim: A diet quality index (DQI) is a tool that provides an overall score of an individual''s dietary intake when assessing compliance with food-based dietary guidelines. A number of DQIs have emerged, albeit their associations with health-related outcomes are debated. The aim of the present study was to assess whether adherence to dietary intervention, and the overall quality of the diet, can predict body composition changes. Methods: To this purpose, overweight/obese adolescents (n = 117, aged: 13–16 years; 51 males, 66 females) were recruited into a multi-component (diet, physical activity and psychological support) family-based group treatment programme. We measured the adolescents’ compliance and body composition at baseline and after 2 months (intensive phase) and 13 months (extensive phase) of follow-up. Also, at baseline, after 6 months, and at the end of follow-up we calculated the DQI. Results: Global compliance with the dietary intervention was 37.4% during the intensive phase, and 14.3% during the extensive phase. Physical activity compliance was 94.1% at 2-months and 34.7% at 13months and psychological support compliance were growing over the intervention period (10.3% intensive phase and 45.3% during extensive phase). Adolescents complying with the meal frequency criteria at the end of the extensive phase had greater reductions in FMI z-scores than those did not complying (Cohen''s d = 0.53). A statistically significant association was observed with the diet quality index. DQI-A variation explained 98.1% of BMI z-score changes and 95.1% of FMI changes. Conclusions: We conclude that assessment of changes in diet quality could be a useful tool in predicting body composition changes in obese adolescents involved in a diet and physical activity intervention programme backed-up by psychological and family support
Investigación en color y calidad de alimentos
En esta ponencia se pretende presentar a los alumnos de la Escuela Politécnica Superior, las líneas de investigación del grupo Color y Calidad de Alimentos de la Universidad de Sevilla (AGR225, PAIDI) y las posibilidades de realizar Trabajos postdoctorales o continuar las salidas profesionales en el campo de industrias alimentarias.This paper tries to introduce to the student of Polytechnic School, the research lines of Color and Food Quality Group of the University of Seville (AGR225, PAIDI), and the possibilities of carrying out postdoctoral works or continuing the career in the field of food industries
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative
Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research
Use of anticoagulants and antiplatelet agents in stable outpatients with coronary artery disease and atrial fibrillation. International CLARIFY registry
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