Analysis of the use of Facebook in higher education from the perspective of computer-supported collaborative learning

El objetivo del presente trabajo es analizar, desde la perspectiva del Aprendizaje colaborativo a través de la computadora, el uso de Facebook en un taller de lectoescritura de de la Universidad Nacional de General Sarmiento (Buenos Aires, Argentina). Esto nos ha permitido extraer algunas observaciones y sugerencias respecto del uso de las redes sociales en la educación universitaria.The aim of this study is to analyze the use of Facebook in a reading and writing Workshop at University of General Sarmiento (Buenos Aires, Argentina) from the perspective of Computer-supported collaborative learning. Regarding this, some remarks and suggestions are pointed in relation to the use of social networks in higher education.Fil: Alvarez, Guadalupe. Universidad Nacional de General Sarmiento. Instituto del Desarrollo Humano; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: López, Marta. Universidad de Barcelona; Españ

Data Fusion based on Game Theory for Speaker Diarization

A novel algorithm based on bimatrix game theory has been developed to improve the accuracy and reliability of a speaker diarization system. This algorithm fuses the output data of two open-source speaker diarization programs, LIUM and SHoUT, taking advantage of the best properties of each one. The performance of this new system has been tested by means of audio streams from several movies. From preliminary results on fragments of five movies, improvements of 63% in false alarms and missed speech mistakes have been achieved with respect to LIUM and SHoUT systems working alone. Moreover, we also improve in a 20% the number of recognized speakers, getting close to the real number of speakers in the audio strea

A Robust Bayesian Dynamic Linear Model for Latin-American Economic Time Series: "The Mexico and Puerto Rico Cases"

The traditional time series methodology requires at least a preliminary transformation of the data to get stationarity. On the other hand, Robust Bayesian Dynamic Models (RBDMs) do not assume a regular pattern or stability of the underlying system but can include points of statement breaks. In this paper we use RBDMs in order to account possible outliers and structural breaks in Latin-American economic time series. We work with important economic time series from Puerto Rico and Mexico. We show by using a random walk model how RBDMs can be applied for detecting historic changes in the economic inflation of Mexico. Also, we model the Consumer Price Index (CPI), the Economic Activity Index (EAI) and the total number of employments (TNE) economic time series in Puerto Rico using local linear trend and seasonal RBDMs with observational and states variances. The results illustrate how the model accounts the structural breaks for the historic recession periods in Puerto Rico

What if it never happened? Subjective treatment effects of a negative shock on youth labour market outcomes in developing countries

This paper examines the subjective treatment effects of a negative shock created by the COVID-19 pandemic on the labour market outcomes of young adults in India, Peru, and Vietnam. We leverage subjective counterfactual outcomes at the individual-level that were purposely collected from over 7,000 individuals to this aim. Our findings suggest that the shock denied employment opportunities and reduced earnings. On average, the pandemic reduced monthly earnings by 19.4% and employment levels by 17.5% in our three-country-sample. Country-specific magnitudes are lowest for India and highest for Vietnam. However, these average effects belie that a substantial proportion of individuals, particularly those from disadvantaged backgrounds, are pushed into employment by the pandemic. This frequently comes at the expense of their education, hinting at youth labour acting as a buffer against transitory shocks. According to our findings, the perceived effects of the pandemic on labour market outcomes carry important implications for young people's well-being and behaviour. Individuals who are denied employment display significantly higher rates of anxiety, lower rates of COVID-19 vaccination, and lower desired fertility

Synthesis of fatty acid methyl esters from pomace oil catalyzed by zinc stearate: A kinetic study of the transesterification and esterification reactions

In this work, the simultaneous transesterification and esterification reactions of olive pomace oil with methanol catalyzed by zinc stearate were studied. This catalyst is a crystalline solid at room temperature, but it is soluble in the reaction medium at reaction temperature. Zinc stearate has surfactant properties that cause the formation of an emulsion in the reaction system. The stability of the emulsion formed in the oil-methanol-catalyst system was compared to that in the FAME (fatty acid methyl esters)-methanol-catalyst system. It was observed that the emulsion formed in the presence of high amounts of FAME is much more unstable, which makes the catalyst easy to separate from the reaction products. The kinetics of esterification and transesterification were also studied. All the kinetic and equilibrium constants were determined with a complete model, considering the three stepwise reactions corresponding to the transesterification of triglycerides and the esterification of free fatty acids. The parameters obtained were used to model the operating conditions that would allow obtaining biodiesel that meets the quality standards.Fil: Alvarez Serafini, Mariana Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Tonetto, Gabriela Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentin

Psychometric properties of the healthy lifestyle questionnaire for ecuadorian university students (EVS-EUE)

University students are considered a key population in promoting and establishing healthy lifestyles that will ensure a full life for the next generations. The purpose of this study was to do a cultural and linguistic adaptation of the healthy lifestyle questionnaire for Ecuadorian university students (EVS-EUE). Two thousand, one hundred and eight (2108) students from 17 to 19 years old (27%), 20 to 24 years old (57%), and over 24 years old (16%) participated (M = 21.81 years; SD = 3.04). A confirmatory factor analysis, internal consistency analysis, and concurrent validity were conducted. The results of the EVS-EUE Questionnaire presented adequate values (x2/d.f = 9.02, Comparative Fit Index (CFI) = 0.96, Incremental Fit Index (IFI) = 0.96, McDonald Fit Index (MFI) = 0.91, Adjusted Goodness of Fit Index (AGFI) = 0.94, Root Mean Square Error of Approximation (RMSEA) = 0.06, Standardized Root Mean Square Residual (SRMR) = 0.03). The internal consistency showed values above 0.70, and analyzed its concurrent validity, reaching adequate values. This study has provided a valid and reliable questionnaire to evaluate healthy lifestyles in the Ecuadorian population.This study was carried out thanks to the contribution of the Ministry of Economy and Infrastructure of the Council of Extremadura, through the European Regional Development Fund—A way to make Europe. (GR18129)

Picado de metales puros

La corrosión de los metales suele presentarse bajo diferentes formas, siendo una de las más frecuentes la corrosión por picado. El objeto de este trabajo fué estudiar el picadode una serie de metales puros en diferentes electrolitos para así alcanzar un mejor conocimiento de los fenómenos que conducen a la aparición de esta forma de ataque localizado, pues se piensa que sólo a través del mismo se podrá tener un criterio adecuado para el desarrollo de métodos de control y de materiales resistentes, que es el fin último de todo estudio de un proceso de corrosión. En particular, en este trabajo se buscó indagaren la naturaleza del potencial crítico de picado, el cual ha sido objeto de numerosas discusiones e interpretaciones sin que haya sido posible, hasta el presente, encontrar una explicación totalmente satisfactoria para el mismo. Para ello se eligió estudiar el picado en sistemas tales como cinc, cadmio, hierro y níquel en diferentes medios corrosivos y el trabajo se orientó a comparar el comportamiento de estos metales en soluciones neutras o alcalinas con el comportamiento del mismo metal en soluciones ácidas semejantes a las existentes en el interior de una picadura. Además, se buscó conocer el efecto de distintas variables, tales como pH,ión agresivo, concentración de ión agresivo y presencia de aniones de ácido débil sobre el potencial de picado de los mismos. El efecto del agregado de pequeñas cantidades de aleantes fué determinado para el caso particular del picado del Cinc en soluciones de cloruro de sodio. Los resultados obtenidos indican que en los sistemas estudiados la aparición de picado está asociada a la existencia de una acidificacíón localizada en la interfase metal-solucióny que el potencial de picado es el minimo valor de potencial al cual dicha acidificación puede subsistir en contacto con el metal. El trabajo fué desarrollado en tres capitulos. En el Capitulo 1 se hace una reseña bibliográfica en la que se detallan los principales modelos propuestos para explicar el fenómeno de picado asi como las distintas variables que influyen sobre el mismo. En el Capítulo 2 se describen los métodos experimentales utilizados en este trabajo y los resultados obtenidos. En el Capítulo 3 se analizan los mencionados resultados y se indican las conclusiones a que se llegó. Finalmente se incluyen dos Apéndices, el primero dedicado al cálculo de los diagramas de equilibrio electroquimico potencial-pH de los sistemas Cd-I(-)-H20 y Cd-Cl(-)-H20 y el segundo a la descripción del tratamiento matemático utilizado para calcular los perfiles de concentraciones iónicas en el interior de una picadura unidireccional.Fil: Alvarez, Marta Graciela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Internações de idosos por condições sensíveis à atenção primária no Estado de Santa Catarina

The aim was to analyze the behavior of causes and length of stay of hospitalizations of elderly people due to conditions sensitive to primary care in the State of Santa Catarina in the period between 2008 and 2015. Authorizations for hospital admissions AIH/SUS filtered by the cause and length of stay of the patients were used hospitalizations of elderly people due to conditions sensitive to primary care, from 2008 to 2015, in Santa Catarina. Standardized data by age using the direct method and statistical analysis using Joinpoint Regression® software. In asthma, chronic obstructive pulmonary disease and heart failure, a decrease in variation was observed during the study period. Ear, nose and throat infections, bacterial pneumonia and angina increase. The variation of hospital stays of up to seven days decreased and a significant increase, between 15 and 30 days. Cerebrovascular diseases were the main responsible for hospitalizations with length of stay over 15 days. The increase in the length of hospital stay has a negative impact on the life of the elderly, their family and the health system. Health professionals and authorities should be attentive to the expansion of care actions at the level of primary care for the elderly.Objetivou-se analisar o comportamento das causas e tempo de permanência das internações de idosos por condições sensíveis à atenção primária no Estado de Santa Catarina no período entre 2008 e 2015. Utilizou-se as autorizações de internações hospitalares AIH/SUS filtrados pela causa e tempo de permanência das internações de idosos por condições sensíveis à atenção primária, no período de 2008 a 2015, em Santa Catarina. Realizou a padronização dos dados por idade através do método direto e a análise estatística por meio  de Software Joinpoint Regression®. Na asma, doença pulmonar obstrutiva crônica e insuficiência cardíaca, observou-se queda de variação no período do estudo. Já as infecções de ouvido nariz e garganta, pneumonias bacterianas e angina, aumento. Diminuiu a variação de permanência hospitalar de até sete dias e aumento significativo, entre 15 e 30 dias.  As doenças cerebrovasculares foram as principais responsáveis pelas internações com tempo de permanência acima de 15 dias. O aumento do tempo de permanência hospitalar impacta negativamente a vida do idoso, sua família e para o sistema de saúde. Profissionais e autoridades de saúde devem estar atentos a ampliação de ações de cuidado à nível de atenção primária às pessoas idosas