1,643 research outputs found

    People are the message? Social mobilization and social media in Brazil

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    In June 2013, protesters took to the streets of hundreds of Brazilian cities. The mobilizing factor was the rising fares of public transportation, which precipitated a wave of discontentment characterized by a mix of demands for better public services and changes in the discredited democratic institutions. This article discusses the role of social media in the protests and how such use configures a paradigmatic example of how communication occurs in network societies. To frame the discussion, we examine social media appropriation for the purposes of political participation through a survey applied online in 17 countries and an in-depth analysis of protests in Brazil. Looking at the Brazilian protests, the ways in which the appropriation of social media occurred and institutional responses to demonstrations developed, we argue that in the network society, the people, and no longer the media, are the message.info:eu-repo/semantics/publishedVersio

    UNR facilitates the interaction of MLE with the lncRNA roX2 during Drosophila dosage compensation

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    Dosage compensation is a regulatory process that balances the expression of X-chromosomal genes between males (XY) and females (XX). In Drosophila, this requires non-coding RNAs and RNA-binding proteins (RBPs) whose specific functions remain elusive. Here we show that the Drosophila RBP UNR promotes the targeting of the activating male-specific-lethal complex to the X-chromosome by facilitating the interaction of two crucial subunits: the RNA helicase MLE and the long non-coding RNA roX2

    Structural characterization of lead metaniobate thin films deposited by pulsed laser ablation

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    The ferroelectric polymorph of lead metaniobate (PbNb2O6) presents an orthorhombic structure that is metastable at room temperature. This phase is obtained by quenching from high temperature. The fabrication of lead niobate thin films with this orthorhombic form has been reported to be difficult due to the presence of phases with the rhombohedric form or other non-stoichimetric phases. In this work, lead niobate thin films have been prepared by laser ablation, at different oxygen pressures and with different substrate temperatures. Their structure was studied by X-ray diffraction and their surface was examined by scanning electron microscopy (SEM). The results show that for low deposition temperatures the films presented a rhombohedric-PbNb2O6 structural phase. As Tdep increases the films started to develop an orthorhombic- PbNb2O6 structure that appeared at 400ºC and remains up to 600ºC. For lower oxygen pressure during deposition, a mixture of this phase and other orthorhombic lead deficient phases are present in the films. On the other hand, by increasing the oxygen pressure the lead deficient phases are strongly reduced and the films present only the orthorhombic- PbNb2O6 structure.(undefined

    Stabilized leachates: Ozone-activated carbon treatment and kinetics

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    Ozone has been used as a pre-oxidation step for the treatment of stabilized leachates. Given the refractory nature of this type of effluents, the conversion of some wastewater quality parameters has been moderate after 1 h of ozonation (i.e. 30% chemical oxygen demand (COD) depletion). Ozone uptake was calculated in the interval 1.3–1:5 g of ozone per gram of COD degraded. An optimum dose of ozone has been experienced in terms of biodegradability of the processed effluent (60 min of treatment, 1 103 mol L1 ozone inlet feeding concentration and 50 L h1 gas flowrate). pH and other typical hydroxyl radical generator systems exerted no influence on the efficiency of the process, suggesting the negligible role played by the indirect route of oxidation (generation of hydroxyl radicals). The ozonated effluent was thereafter treated in a second adsorption stage by using a commercial activated carbon. Removal levels up to 90% of COD in approximately 120 h were experienced for adsorbent dosages of 30 g L1 : Both steps, the single ozonation and the adsorption stage have been modelled by using different pseudoempirical models. r 2003 Elsevier Ltd. All rights reserved

    Restricción de crecimiento intrauterino

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    ResumenLa restricción del crecimiento intrauterino es una importante causa de morbilidad y mortalidad perinatal, con consecuencias que pueden tener implicancias hasta en la vida adulta. No existen estrategias terapéuticas a la fecha por lo que, su manejo consiste principalmente en su diagnóstico y seguimiento para definir el momento de finalizar el embarazo, equilibrando los riesgos de prematurez con la morbimortalidad esperada para cada condición fetal. En el presente artículo se describen las claves del diagnóstico, clasificación y seguimiento de acuerdo a estándares actuales que permitan el adecuado manejo clínico.SummaryIntrauterine growth restriction is a major cause of perinatal morbidity and mortality with consequences that may have implications even in adulthood. No treatment have currently available, so, management is mainly based in diagnosis and monitoring in order to choose the right time to delivery, balancing the risks of prematurity with the expected morbidity and mortality. A precise diagnosis, classification and fetal surveillance according to current standards is discussed

    Nanostructured micelle nanotubes self-assembled from dinucleobase monomers in water

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    Despite the central importance of aqueous amphiphile assemblies in science and industry, the size and shape of these nano-objects is often difficult to control with accuracy owing to the non-directional nature of the hydrophobic interactions that sustain them. Here, using a bioinspired strategy that consists of programming an amphiphile with shielded directional Watson–Crick hydrogen-bonding functions, its self-assembly in water was guided toward a novel family of chiral micelle nanotubes with partially filled lipophilic pores of about 2 nm in diameter. Moreover, these tailored nanotubes are successfully demonstrated to extract and host molecules that are complementary in size and chemical affinityFunding from the European Research Council (ERC-Starting Grant 279548 PROGRAM-NANO) and MINECO (CTQ2014-57729-P and CTQ2017-84727-P) is gratefully acknowledged

    Diagnosis of Tuberculosis among Children and Adolescents

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    The authors discuss the challenging aspects of the diagnosis of tuberculosis in children and adolescents, since there is no gold standard for its diagnosis. The different clinical and radiological presentations and the low bacteriological positivity of tuberculosis in childhood are grounds for confrontation to the present. Immunological tests called interferon gamma release assays (IGRAs) failed to overcome the tuberculin skin test in practice. Advances with nucleic acid amplification tests, on the other hand, have contributed to the diagnosis of tuberculosis among adolescents. Standardized systems for diagnosis can be useful as tools for screening or for decision‐making in childhood tuberculosis
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