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Buenos Aires, Argentina

The National University of General Sarmiento is a national university in Argentina, founded in 1993. It is located in the Malvinas Argentinas partido, in the Gran Buenos Aires urban area. Wikipedia.

Mietta J.L.,University of Buenos Aires | Jorge G.,National University of General Sarmiento | Martin Negri R.,University of Buenos Aires
Smart Materials and Structures

A flexible, anisotropic and portable stress sensor (logarithmic reversible response between 40-350 kPa) was fabricated, in which i) the sensing material, ii) the electrical contacts and iii) the encapsulating material, were based on polydimethylsiloxane (PDMS) composites. The sensing material is a slide of an anisotropic magnetorheological elastomer (MRE), formed by dispersing silver-covered magnetite particles (Fe3O4@Ag) in PDMS and by curing in the presence of a uniform magnetic field. Thus, the MRE is a structure of electrically conducting pseudo-chains (needles) aligned in a specific direction, in which electrical conductivity increases when stress is exclusively applied in the direction of the needles. Electrical conductivity appears only between contact points that face each other at both sides of the MRE slide. An array of electrical contacts was implemented based on PDMS-silver paint metallic composites. The array was encapsulated with PDMS. Using Fe 3O4 superparamagnetic nanoparticles also opens up possibilities for a magnetic field sensor, due to the magnetoresistance effects. © 2014 IOP Publishing Ltd. Source

Guala S.D.,National University of General Sarmiento | Vega F.A.,University of Vigo | Covelo E.F.,University of Vigo
Environmental Pollution

A mathematical interaction model, validated by experimental results, was developed to modeling the metal uptake by plants and induced growth decrease, by knowing metal in soils. The model relates the dynamics of the uptake of metals from soil to plants. Also, two types of relationships are tested: total and available metal content. The model successfully fitted the experimental data and made it possible to predict the threshold values of total mortality with a satisfactory approach. Data are taken from soils treated with Cd and Ni for ryegrass (Lolium perenne, L.) and oats (Avena sativa L.), respectively. Concentrations are measured in the aboveground biomass of plants. In the latter case, the concentration of metals in different parts of the plants (tillering, shooting and earing) is also modeled. At low concentrations, the effects of metals are moderate, and the dynamics appear to be linear. However, increasing concentrations show nonlinear behaviors. © 2010 Elsevier Ltd. All rights reserved. Source

Arrossi S.,CONICET | Maceira V.,National University of General Sarmiento | Paolino M.,CONICET | Sankaranarayanan R.,International Agency for Research on Cancer IARC

In Argentina, human papillomavirus (HPV) vaccination was approved in 2006, but not included in the National Immunization Program. In 2008 a mass media campaign was carried out by a cancer Non-Governmental Organization (NGO), but it was stopped due to criticisms about the publicity. In October 2011 the Ministry of Health (MoH) has introduced HPV vaccination in the National Immunization Program. In this context, to assure high HPV vaccine coverage, evidence is needed on factors both associated to vaccine acceptability and uptake. In 2009-2010 we carried out a population-based survey among a representative sample of 1200 women aged 18-49 years from the Metropolitan Area of Buenos Aires. The objective was twofold: first to analyze socio-demographic determinants of women's knowledge on HPV vaccine and secondly, determinants of actual HPV vaccine uptake and acceptability in Argentina after the above-mentioned vaccine advertising shown in mass media in the year 2008.We analyzed vaccine uptake/acceptability separately for women and for their daughters aged 9-15, and willingness to vaccinate one's daughter younger than 9 to receive future HPV vaccination. Results of the 1200 women interviewed, 438 women (36.5%) knew the HPV vaccine and 303 (25%) remembered the mass media advertisement about HPV vaccination. When asked whether she would get vaccinated after having seen/heard the advertisement, around 75% (n= 226) of women answered surely/probably yes. No significant differences in socio-demographic characteristics were found among women who would or not get vaccinated. When surveyed, 6 women had been vaccinated. Main reasons for non-vaccination were: "Doctor did not mention/recommend it" (34.1%) and "Vaccine is too expensive" (15.7%). No woman had had their 9-15 year-old daughter vaccinated. Among women who only had at least one daughter under 9 (n= 278), 74% answered that they would get their daughter vaccinated if they were pre-adolescents. The conclusion is that, in Argentina, the potential acceptability of the vaccine is high, given that there is acceptance among the professional community, physicians recommend it, and vaccine is affordable. © 2012 Elsevier Ltd. Source

Saravia L.A.,National University of General Sarmiento

Multifractals have been applied to characterize complex communities in a spatial context. They were developedfor nonlinear systems and are particularly suited to capture multiplicative processes observed in ecologicalsystems. Multifractals characterize variability in a scale-independent way within an experimental range. Ihave developed an open-source software package to estimate multifractals using a box-counting algorithm(available from https://github.com/lsaravia/mfsba and permanently available at doi: 10.5281/zenodo.8481).The software is specially designed for two dimensional (2D) images such as the ones obtained from remotesensing, but other 2D data types can also be analyzed. Additionally I developed a new metric to analyze multispecies spatial patterns with multifractals: spatial rank surface, which is included in the software. © 2014 Saravia LA. Source

Suarez D.,University of Aalborg | Suarez D.,National University of General Sarmiento
Research Policy

The concept of persistence is generally used to define the positive relationship between past and present innovations, which is explained by feedback and accumulation processes triggered by the firm's past results. This paper states that changes in the economic or institutional conditions of the environment impact on the type of profitable innovations, and past innovations might not be suitable for the new environment. As a result, firm's innovative behavior might change, which means that the firm's set of decisions about engaging in the seek for innovations or not and, if so, the set of investments and capabilities it allocates to innovate could be modified. Empirical evidence is provided to reject the persistence hypothesis and to show that past innovations do not necessarily impact present ones. This paper examines the relationship between past and present innovations for a group of Argentinean firms during 1998-2006, which coincides with a period of macroeconomic instability. Results suggest that persistence has to be analyzed in terms of a dynamic firm's innovative behavior - regardless of its results - and how it allows the firm to accumulate competences and resources, which increases the odds of successfully responding to changes in the environment and continuing to innovate. © 2013 Elsevier B.V. Source

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