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Zika virus became an epidemic in Brazil from early 2015, with the first cases of suspected microcephaly caused by Zika virus confirmed in the states of Rio Grande do Norte and Pernambuco. Since then, research has highlighted the need for further investigations to better understand the physiology, symptoms and prognoses in order to better follow up children with congenital Zika virus syndrome. The impact of Zika virus on the development of children with microcephaly is still unknown. Congenital Zika virus infection syndrome has its worst expression when infection occurs in the first trimester of pregnancy. It is also known that the pattern of neurological disorder varies depending on the age at which the mother was infected. However, changes in central functions are expected in most patients with microcephaly and significantly impar neuropsychomotor development, vision and hearing. So far, studies show controversial results. This investigation was an opportunity to learn about the influence of this neurological condition on the electrophysiological parameters and also made possible to compare the findings of the Early Language Milestone Scale with the results of the electrophysiological exams. This is a descriptive cross-sectional study developed in the Audiology Sector of the two brazilians Universities. The study included 20 children of both genders, composed by the research group, with microcephaly due to congenital Zika virus syndrome and by the control group, comparison group. In this research cortical auditory evoked potential exams were performed and the language development scale, aiming to apply electrophysiological and behavioral measures to assess hearing and language. Longer values were observed in the latency of the N1-P2 components and greater amplitude of the N1 component of the auditory cortical potential in the research group. The scale also showed significant impairment in the linguistic development of the children in the research group. The Smart tools EP software used for neural response analysis showed abnormalities in neurotransmission of frequency spectral characteristics in the auditory pathway in children with Zika microcephaly in frequency domain analysis. The software calculations showed much higher slope and total area values in this population, also suggesting failure in the automated perception control of acoustic changes related to the activity of the N1 component. Electrophysiological and behavioral measurements showed a pattern of atypical development of the auditory and linguistic system in children with suspected microcephaly by Zika virus. [ABSTRACT FROM AUTHOR]

Some precipitation reactions of superduplex stainless steels (SDSS) can improve hardness, yield, and ultimate strength, but with substantial decrease of corrosion resistance. One of these reactions is the spinodal decomposition of ferrite into Cr-rich fine precipitates (α′) and Cr-depleted matrix during low temperature aging. In this work, the effect of the α′ precipitation on the pitting corrosion resistance was investigated. The results showed that short duration heat treatments at 475 °C do not decrease the pitting corrosion resistance, but increase the hardness of UNS S32750 and S32760 SDSS. The limits of heat treatment duration for both steels were determined. [ABSTRACT FROM AUTHOR]

The paper presents a methodology that provides a solution for the one-day-ahead predispatch problem considering the evaluation and improvement of the voltage stability margin by optimising reactive-power injections by generators and synchronous condensers. Modal participation factors are used to define penalty indices for all generators, which are then added to the optimal power flow objective function. This identifies the most adequate reactive-power injection for each generator or synchronous condenser, to maximise voltage stability margins. The results obtained for the New England test system and a version of the Southwest Brazilian system show that the proposed methodology leads to significant improvement in voltage stability margin for all the critical time intervals of the day. The occurrence of contingencies in the system is also considered. One clear advantage of the proposed methodology is that the optimal (economical) solution for active power injection of generators is maintained unchanged, which means that there will be no impact on the energy targets of the hydroelectric plants, nor on total generation costs. Hence, the voltage stability margin is improved by simply managing reactive-power dispatch. [ABSTRACT FROM AUTHOR]

The quality of a SrTiO3 tunnel barrier deposited by pulsed laser deposition on SrTiO3 (001)∥Sr2FeMoO6 is investigated. Epitaxy and two-dimensional growth are obtained and the root-mean-square roughness is 0.3 nm. The distribution of the local current measured by conductive atomic force microscopy indicates that hot spots are almost absent. The standard deviation of the barrier thickness distribution is lower than 0.05 nm. Current-voltage characteristics of patterned magnetic tunnel junctions provide evidence of the high quality of the barrier. The electrical properties of the SrTiO3 barrier are at least as good as the ones obtained by sputtering or e-beam evaporation. [ABSTRACT FROM AUTHOR]