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Nuestra Señora del Rosario de Caa Catí, Argentina

Meijide F.J.,University of Buenos Aires | Meijide F.J.,CONICET | Rey Vazquez G.,University of Buenos Aires | Rey Vazquez G.,CONICET | And 5 more authors.
Ecotoxicology and Environmental Safety | Year: 2016

Estrogenic chemicals are often detected in the aquatic environment and can negatively affect animal development and reproduction. In teleost fishes, the hormonal regulation during a critical period of larval development has a strong influence on gonadal sex differentiation; thus this process may be affected by the exposure to environmental estrogens. In this study, we first assessed the lethal acute toxicity of the natural estrogen 17β-estradiol (E2) and the weaker estrogen mimics 4-tert-octylphenol (OP) and 4-nonylphenol (NP) on larval stages of the South American cichlid fish Cichlasoma dimerus. In a further experiment, we analyzed the effects of chronic waterborne exposure to E2 and OP on gonad development and sex differentiation. Exposure to high concentrations of E2 had a pronounced feminizing effect directing sex differentiation towards ovarian development, while testis development was inhibited at a lower, environmentally relevant concentration. Among OP-exposed fish, 15-38.5% of the males exhibited testicular oocytes (TOs), a commonly reported biomarker of estrogenic exposure. However, since TOs were also recorded in control males and the proportion of males with TOs was not significantly higher in OP treatments, their occurrence could not be attributed to OP exposure. In addition, TOs did not seem to impair male gonad development and functionality since normal spermatogenesis was observed in testes of OP-treated fish. These results indicate that E2 occurring in the South American aquatic environment may affect male reproductive development and pose a risk for wild C. dimerus, especially under prolonged exposure, while the effects of weaker xenoestrogens such as OP would be negligible for gonad development in this species. As illustrated by this study, the natural occurrence of TOs indicates that conclusions concerning the causes of this phenomenon must be drawn with care. © 2015 Elsevier Inc.

Quinteros C.,GIA | Zazpe R.,CIC Nanogune | Marlasca F.G.,GIA | Golmar F.,INTI | And 6 more authors.
Journal of Applied Physics | Year: 2014

We report on the fabrication and characterization of metal/insulator/metal capacitor like devices, with both rectifying and hysteretic features. Devices are formed by two junctions, Ti/HfO2 and Co/HfO2. Each junction exhibits highly repetitive hysteretic I-V curves with a sharp transition from a high to a low resistance state (3-4 orders of magnitude jump). The opposite transition (from low to high) is induced by polarity reversal. The rectifying non-crossing characteristics of the I-V branches denote their potential use as a multifunctional device, acting as a built-in rectifier and memory cell in a single device. Based on the phenomenological model description by Zazpe [Appl. Phys. Lett. 103, 073114 (2013)], we propose a circuital equivalent representation supported on switchable rectifying junctions. By exploring different electrode connections, we disentangle the role of the bulk transport in HfO2 devices. © 2014 AIP Publishing LLC.

Savarin A.,INTI
20th IMEKO World Congress 2012 | Year: 2012

This paper presents the INTI's new uncertainties levels in force measurements and a brief introduction to the developments that are taking place.

Monsalve L.N.,CONICET | Medrano A.V.,INTI | Golmar F.,CONICET | Trupp L.,FCEN UBA | And 2 more authors.
Smart Systems Integration 2016 - International Conference and Exhibition on Integration Issues of Miniaturized Systems, SSI 2016 | Year: 2016

A bis(triarylamine) compound was used as channel for a field effect transistor. The compound was drop-casted onto surface modified gold source and drain electrodes. Low voltage operation and extreme stability was found for these devices, retaining modulation properties for more than 6 months in air without encapsulation.

Perez M.,CNEA | Haro M.S.,CONICET | Sidelnik I.,CONICET | Tozzi L.,INTI | And 5 more authors.
Proceedings of the 2015 Argentine School of Micro-Nanoelectronics, Technology and Applications, EAMTA 2015 | Year: 2015

We present the response of a Commercial-Off-The-Shelf (COTS) CMOS image sensor to different ionizing particles, with the aim of developing a low cost radiation detector. We first analyze the images obtained by exposing the imagers to X-rays from 55Fe, gamma and beta particles from 137Cs. Then the detector is successfully used to monitor different gamma fluxes produced by the RA6 nuclear research reactor, Argentina, during a startup procedure. © 2015 IEEE.

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