Adolescents from low-income sectors: the challenge of studying in a time of digital environments

This paper is about practices and perceptions regarding the study of adolescents from low-income sectors in the City of Buenos Aires. The methodology consisted of 26 in-depth interviews with low-income adolescents and participant observations in twenty cybercafés of the South Area of the City of Buenos Aires. Among the findings, these students highlight that ICTs allow them to handle information in a more agile and entertaining way, more consistent with their daily uses. However, doing research on school content is what students do the least, since adolescents use technology mainly for communicative, social and recreational ends. These adolescents recognise some disadvantages in using ICTs to study: the unreliable information, the difficulty to distinguish which topics related to school content are more appropriate and the disruptive and continuous use of social networks. In this sense, these adolescents tend to have more problems in benefitting from ICTs for academic purposes than other adolescents. While communication and recreational skills tend to be similar, the evaluation of different sources of information and the skill to make complex searches online are usually more strongly developed in adolescents of middle and high-income households. In conclusion, we think it is necessary to take these problems into consideration in the social sciences research of the area and besides when implementing digital literacy programs.Fil: Linne, Joaquín Walter. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigaciones ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Carbon monoxide and oxygen combustion experiments: A demonstration of Mars in situ propellants

The feasibility of using carbon monoxide and oxygen as rocket propellants was examined both experimentally and theoretically. The steady-state combustion of carbon monoxide and oxygen was demonstrated for the first time in a subscale rocket engine. Measurements of experimental characteristic velocity, vacuum specific impulse, and thrust coefficient efficiency were obtained over a mixture ratio range of 0.30 to 2.0 and a chamber pressures of 1070 and 530 kPa. The theoretical performance of the propellant combination was studied parametrically over the same mixture ratio range. In addition to one dimensional ideal performance predictions, various performance reduction mechanisms were also modeled, including finite-rate kinetic reactions, two-dimensional divergence effects and viscous boundary layer effects

Performance and heat transfer characteristics of a carbon monoxide/oxygen rocket engine

The combustion and heat transfer characteristics of a carbon monoxide and oxygen rocket engine were evaluated. The test hardware consisted of a calorimeter combustion chamber with a heat sink nozzle and an eighteen element concentric tube injector. Experimental results are given at chamber pressures of 1070 and 3070 kPa, and over a mixture ratio range of 0.3 to 1.0. Experimental C efficiency was between 95 and 96.5 percent. Heat transfer results are discussed both as a function of mixture ratio and axial distance in the chamber. They are also compared to a Nusselt number correlation for fully developed turbulent flow

Are the Central and Eastern European transition countries still vulnerable to a financial crisis? Results from the signals approach

The aim of paper is to analyse the vulnerability of the Central and Eastern European accession countries to the EU as well as that of Turkey and Russia to a financial crisis. Our methodology is an extension of the signals approach. We develop a composite indicator to measure the evolutin of of the risk potential in each country. Our findings show that crises in Central and Eastern Europe are caused by much the usual suspects s in others emerging markets. In particular an overvalued exchange rate. Weak exports and dwindling currency reserves have good precictive power for assessing crisis vulnerabilities.financial crises; vulnerability indicator; Central and Eastern Europe

Technical prospects for utilizing extraterrestrial propellants for space exploration

NASA's LeRC has supported several efforts to understand how lunar and Martian produced propellants can be used to their best advantage for space exploration propulsion. A discussion of these efforts and their results is presented. A Manned Mars Mission Analysis Study identified that a more thorough technology base for propellant production is required before the the net economic benefits of in situ propellants can be determined. Evaluation of the materials available on the moon indicated metal/oxygen combinations are the most promising lunar propellants. A hazard analysis determined that several lunar metal/LOX monopropellants could be safely worked with in small quantities, and a characterization study was initiated to determine the physical and chemical properties of potential lunar monopropellant formulations. A bipropellant metal/oxygen subscale test engine which utilizes pneumatic injection of powdered metal is being pursued as an alternative to the monopropellant systems. The technology for utilizing carbon monoxide/oxygen, a potential Martian propellant, was studied in subscale ignition and rocket performance experiments

“Now I Do Academic Fast Food”: Grad Students in the ICT’s Era

Together with the widespread use of Information and communication Technologies (ICTs), global changes have taken place in most social environments. This article stands at the intersection of communication and education studies, by investigating the introduction and use of ICTs in students’ learning and everyday life. The aim of our research, indeed, is to explore the transformations in learning and academic information processing habits among students part of the School of Philosophy and Literature and that of Social Sciences at Buenos Aires University. Methodologically, we gathered targeted interviews with students and professors from said faculties (n: 140). Moreover, we undertook on-site observations at university libraries and virtual observations on social network sites and university websites. From the findings a paradox concerning the intensive use of ICTs emerges: greater accessibility, availability and information exchange lead to degrees of ‘distraction’, ‘superficiality’ and ‘speed’ in the fruition and circulation of content. Based on a native category, we have come to call this tendency “academic fast food”

Teen of popular sectors: The challenge of the study in digital environments times

Este artículo tiene como objetivo indagar en las prácticas y percepciones de las TIC en adolescentes de sectores populares de la Ciudad de Buenos Aires. A nivel metodológico, realizamos veinticinco entrevistas en profundidad, una encuesta (n: 450) y observaciones tanto copresenciales como virtuales. Hemos encontrado evidencia empírica que da cuenta de que los adolescentes de sectores medios y populares suelen utilizar las mismas plataformas de comunicación y entretenimiento, además de estar interesados en una mayor utilización de las TIC en la escuela. Si bien la entrega de netbooks estatales en escuelas públicas colabora en la disminución de la brecha digital, se observa que las condiciones de desigualdad socio-económicas y los distintos capitales cognitivos impactan en el uso educativo de las TIC, lo que en ciertos casos tiende a aumentar las diferencias en cuanto a la performance escolar.Este artigo tem como objetivo investigar as práticas e percepções das TICs em adolescentes nos setores populares da cidade de Buenos Aires. No plano metodológico, realizou-se vinte e cinco entrevistas, uma pesquisa (n = 450) e observações tanto co-presenciais como virtuais. Encontrou-se evidências empíricas para perceber que os adolescentes e os meios populares costumam usar as mesmas plataformas de comunicação e entretenimento, além de haver interesse no aumento da utilização das TICs nas escolas. Ao entregar netbooks em escolas públicas estaduais contribui para a redução do não acesso aos meios digitais, nota-se que as condições de desigualdade sócio-econômicas dos diferentes impactos do capital cognitivo da utilização educativa das TIC, que em alguns casos, tende a aumentar as diferenças de desempenho escolar.This article aims to investigate the practices and perceptions of ICT in adolescents popular sectors of the City of Buenos Aires. At the methodological level, we conducted twenty interviews, a survey (n = 450) and both copresenciales as virtual observations. We found empirical evidence to realize that teenagers and grassroots media often use the same communication and entertainment platforms, in addition to being interested in the increased use of ICT in schools. While delivering netbooks in state public schools contributes to the reduction of the digital divide, it is noted that conditions of social and economic inequality and the different cognitive capital impact the educational use of ICT, which in some cases tends to increase the differences in school performance.Fil: Linne, Joaquín Walter. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin