186 research outputs found
Predicting Academic Performance based on Students’ Mathematics Motivation
As national development progressively depends on rapid advances in science and technology which in turn require advanced mathematical skills among the country’s populace, enhancing students’ motivation to learn mathematics skilfully gets more importance than ever before. In this context, a descriptive-regression study was conducted to ascertain the predictive ability of the mathematics motivations of fifty-seven students on their academic performance. Results of the study revealed agreement of students manifesting motivational orientations in learning mathematics in terms of intrinsic & extrinsic goal orientation, task value, and control of learning beliefs. However, they manifest less of self-efficacy in learning mathematics and show a slight of anxiety when they were taking tests. Conducted multiple linear regression analysis showed that intrinsic and extrinsic goal orientations, task value, control of learning beliefs, self-efficacy for learning and performance, and test anxiety, taken in combination, were significant predictors of students’ academic performance. Control of learning beliefs and test anxiety, taken singly, could significantly predict academic performance
Physics of interdependent dynamical processes.
La emergencia de fenómenos colectivos a escalas macroscópicas no observados en escalas microscópicas cuestiona la validez de las teorÃas reduccionistas. Para explicar estos fenómenos se necesitan enfoques sistémicos que den cuenta de los patrones de interacción no triviales existentes entre los constituyentes de los sistemas sociales, biológicos o económicos, lo que ha dado lugar al nacimiento de la disciplina conocida como ciencia de los sistemas complejos. Una vÃa habitual para caracterizar los sistemas complejos ha sido la búsqueda de la conexión entre la estructura de interacciones y el comportamiento colectivo observado en sistemas reales mediante el estudio individual de dinámicas aisladas. No obstante, los sistemas complejos no son inmutables y se encuentran constantemente intercambiando información mediante estÃmulos internos y externos. Esta tesis se centra en la adaptación de modelos sobre diferentes dinámicas en el campo de los sistemas complejos para caracterizar el impacto de este flujo de información, ya sea entre escalas microscópicas y macroscópicas de un mismo sistema o mediante la existencia de interdependencias entre procesos dinámicos que se propagan de forma simultánea.La primera parte de la tesis aborda el estudio dinámicas acopladas en redes de contacto estáticas. Adaptando los modelos compartimentales introducidos en el siglo XX a la naturaleza de cada dinámica, caracterizamos cuatro problemas diferentes: la propagación de patógenos que interactúan, cuya coexistencia puede ser beneficiosa o perjudicial para su evolución, el control de brotes epidémicos con el uso del rastreo de contactos digital, la aparición de movimientos sociales desencadenados por pequeñas minorÃas sociales bien coordinadas y la competencia entre honestidad y la corrupción en las sociedades modernas. En todas estas dinámicas, encontramos que el flujo de información cambia las propiedades crÃticas del sistema asà como algunas de las conclusiones extraÃdas sobre el papel de la estructura de contactos al estudiar cada dinámica de forma individual.La segunda parte de la tesis se centra en el impacto de la movilidad recurrente en la propagación de epidemias en entornos urbanos. Derivamos un modelo sencillo que permite incorporar fácilmente la distribución de la población en las ciudades reales y sus patrones habituales de desplazamiento sin ninguna pérdida de información. Demostramos que los efectos de las polÃticas de contención basadas en la reducción de la movilidad no son universales y dependen en gran medida de las caracterÃsticas estructurales de las ciudades y los parámetros epidemiológicos del virus circulante en la población. En particular, descubrimos y caracterizamos un nuevo fenómeno, el detrimento epidémico, que refleja el efecto beneficioso de la movilidad en algunos escenarios para contener un brote epidémico. Por último, exploramos tres casos de estudio reales, mostrando que nuestro modelo permite capturar algunos de los mecanismos que han convertido a los núcleos urbanos en importantes focos de contagio en recientes epidemias y que el modelo desarrollado puede servir como base para desarrollar marcos teóricos más realistas que reproducen la evolución de distintas enfermedades como la COVID-19 o el dengue.<br /
La gestión educativa del curriculum en la formación del pedagogo universitario
Educational management is an act that has multiple implications in different ways, in this paper it is analyzed how it is interpreted and consecrated in the degree of pedagogy of the Universidad Veracruzana in relation to its model and educational plan, considering different implications methodologies such as documentary research, until reaching the process of understanding the new implications in the training of educators.La gestión educativa es un acto que tienen múltiples implicaciones en diferentes formas, en el presente escrito se analiza como esta se ve interpretada y consagrada en la licenciatura de pedagogÃa de la Universidad Veracruzana en relación con su modelo y plan educativo, considerando diferentes implicaciones metodologÃas como la investigación documental, hasta llegar al proceso de entender las nuevas implicaciones en la formación de los educadores
A school-based intervention incorporating smartphone technology to improve health-related fitness among adolescents: Rationale and study protocol for the NEAT and ATLAS 2.0 cluster randomised controlled trial and dissemination study
Introduction Physical inactivity has been described as a global pandemic. Interventions aimed at developing skills in lifelong physical activities may provide the foundation for an active lifestyle into adulthood. In general, school-based physical activity interventions targeting adolescents have produced modest results and few have been designed to be \u27scaled-up\u27 and disseminated. This study aims to: (1) assess the effectiveness of two physical activity promotion programmes (ie, NEAT and ATLAS) that have been modified for scalability; and (2) evaluate the dissemination of these programmes throughout government funded secondary schools. Methods and analysis The study will be conducted in two phases. In the first phase (cluster randomised controlled trial), 16 schools will be randomly allocated to the intervention or a usual care control condition. In the second phase, the Reach, Effectiveness, Adoption, Implementation and Maintenance (Re-AIM) framework will be used to guide the design and evaluation of programme dissemination throughout New South Wales (NSW), Australia. In both phases, teachers will be trained to deliver the NEAT and ATLAS programmes, which will include: (1) interactive student seminars; (2) structured physical activity programmes; (3) lunch-time fitness sessions; and (4) web-based smartphone apps. In the cluster RCT, study outcomes will be assessed at baseline, 6 months (primary end point) and 12-months. Muscular fitness will be the primary outcome and secondary outcomes will include: objectively measured body composition, cardiorespiratory fitness, flexibility, resistance training skill competency, physical activity, self-reported recreational screen-time, sleep, sugar-sweetened beverage and junk food snack consumption, self-esteem and well-being
MetodologÃa DMAIC de Lean Seis Sigma: Una revisión en el contexto del ruido industrial - sector metalmecánico
The most common dangers in the industrial field are physical, noise being the most abundant, work and development force us to live in an environment in which the world of sounds becomes aggressive for man, so that noise can be considered as a significant pollutant today. The main objective was to qualitatively analyze the scientific literature available in the official databases and websites of Scielo, Redalyc and Google Scholar, using as search words: industrial noise, metalworking industry, Lean Six Sigma, DMAIC. Relevant information related to the proposed objective was obtained, which is presented in three sections: Lean Six Sigma, DMAIC, industrial noise in metalworking. The Lean Six Sigma methodology with the DMAIC stages can be used to reduce operational variability and reduce noise as an industrial pollutant, measure the sound pressure level for each machine and operator after implementing control measures in the individual, medium and source, indicate that sound pressure levels decrease significantly.Los peligros en el ámbito industrial más comunes son los fÃsicos, siendo el ruido el de mayor abundancia, el trabajo y el desarrollo nos obligan a vivir en un entorno en el cual el mundo de los sonidos se vuelve agresivo para el hombre, de manera que se puede considerar al ruido como un significativo contaminante en la actualidad. El objetivo principal fue analizar cualitativamente la literatura cientÃfica disponible en las bases de datos y páginas web oficiales de Scielo, Redalyc y Google Académico, utilizando como palabras de búsqueda: ruido industrial, industria metalmecánica, Lean Seis Sigma, DMAIC. Se obtuvo información relevante relacionada con el objetivo propuesto, que se presenta en tres apartados: Lean Seis Sigma, DMAIC, ruido industrial en la metalmecánica. La metodologÃa Lean Seis Sigma con las etapas DMAIC puede ser utilizada para reducir la variabilidad operacional y reducir el ruido como contaminante industrial, medir el nivel de presión sonora por cada máquina y operador después de implementar medidas de control en el individuo, medio y fuente, indican que los niveles de presión sonora disminuyen significativamente
Physics of Neutron Star Crusts
The physics of neutron star crusts is vast, involving many different research
fields, from nuclear and condensed matter physics to general relativity. This
review summarizes the progress, which has been achieved over the last few
years, in modeling neutron star crusts, both at the microscopic and macroscopic
levels. The confrontation of these theoretical models with observations is also
briefly discussed.Comment: 182 pages, published version available at
<http://www.livingreviews.org/lrr-2008-10
Terahertz metamaterials on flexible polypropylene substrate
The final publication is available at Springer via http://dx.doi.org/10.1007/s11468-014-9724-1In this work, we present a metamaterial working at terahertz frequencies made over a flexible polypropylene sub-strate. The experimental measurements, in accordance with the numerical calculations, show the metamaterial reliance on the impinging electric field polarization. The structure s symmetry yields purely electrical resonant responses eliminating bianisotropy effects. The widely used bendable polypropylene polymer may promote the insertion of metamaterial-based structures with special electromagnetic response in a number of objects of our daily lives such as textiles, automotive components, and sensingThis work was supported by the Spanish MICINN under contracts CONSOLIDER EMET CSD2008-00066 and TEC2011-28664-C02-02 and by the Universitat Politecnica de Valencia under the program INNOVA 2011.Ortuño Molinero, R.; GarcÃa Meca, C.; MartÃnez Abietar, AJ. (2014). 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Genetic Ancestry, Social Classification, and Racial Inequalities in Blood Pressure in Southeastern Puerto Rico
The role of race in human genetics and biomedical research is among the most contested issues in science. Much debate centers on the relative importance of genetic versus sociocultural factors in explaining racial inequalities in health. However, few studies integrate genetic and sociocultural data to test competing explanations directly.We draw on ethnographic, epidemiologic, and genetic data collected in Southeastern Puerto Rico to isolate two distinct variables for which race is often used as a proxy: genetic ancestry versus social classification. We show that color, an aspect of social classification based on the culturally defined meaning of race in Puerto Rico, better predicts blood pressure than does a genetic-based estimate of continental ancestry. We also find that incorporating sociocultural variables reveals a new and significant association between a candidate gene polymorphism for hypertension (alpha(2C) adrenergic receptor deletion) and blood pressure.This study addresses the recognized need to measure both genetic and sociocultural factors in research on racial inequalities in health. Our preliminary results provide the most direct evidence to date that previously reported associations between genetic ancestry and health may be attributable to sociocultural factors related to race and racism, rather than to functional genetic differences between racially defined groups. Our results also imply that including sociocultural variables in future research may improve our ability to detect significant allele-phenotype associations. Thus, measuring sociocultural factors related to race may both empower future genetic association studies and help to clarify the biological consequences of social inequalities
High-flux isobutanol production using engineered Escherichia coli: a bioreactor study with in situ product removal
Promising approaches to produce higher alcohols, e.g., isobutanol, using Escherichia coli have been developed with successful results. Here, we translated the isobutanol process from shake flasks to a 1-L bioreactor in order to characterize three E. coli strains. With in situ isobutanol removal from the bioreactor using gas stripping, the engineered E. coli strain (JCL260) produced more than 50Â g/L in 72Â h. In addition, the isobutanol production by the parental strain (JCL16) and the high isobutanol-tolerant mutant (SA481) were compared with JCL260. Interestingly, we found that the isobutanol-tolerant strain in fact produced worse than either JCL16 or JCL260. This result suggests that in situ product removal can properly overcome isobutanol toxicity in E. coli cultures. The isobutanol productivity was approximately twofold and the titer was 9% higher than n-butanol produced by Clostridium in a similar integrated system
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