A comunicação pública a favor da democratização da universidade pública: o caso UFABC nas escolas

The communication in public institutions has mediating character to strengthen the commitment to the citizens and creating channels aimed at high-quality information and transparency. This article deals with public communication, marked by public relations actions in the context of the federal public university through the project called “UFABC in Schools”, Federal University of ABC . The project objectives are to promote the policy of quotas established by the Federal Government and strengthen the relationship with high school students from public schools located in the ABC Paulista region.

A CONSTRUÇÃO DISCURSIVA DA IMAGEM DA ORGANIZAÇÃO PÚBLICA EM UM CONTEXTO REGIONAL POLÍTICO: O caso da UFABC

Esta pesquisa aborda como se constrói a imagem de uma instituição por meio dos discursos elaborados pela organização e pela imprensa nacional e regional. Estuda também os elementos macros que podem influenciar esta construção, em especial quando a organização está instalada em um contexto regional com forte apelo político. Além disso, reflete sobre a responsabilidade social da imprensa na construção da imagem organizacional. Para isso, foi realizada uma discussão procurando alinhar a prática à teoria, perpassando por temas como comunicação pública, o discurso das organizações e a imprensa na construção da imagem, e também a análise de case específico, o da Universidade Federal do ABC. Realizou-se também uma Observação Participante, visto que a pesquisadora está inserida no objeto pesquisado. Esta pesquisa propõe uma contribuição, em especial, aos profissionais e pesquisadores da comunicação pública, ao avaliar em que grau pode ser percebida uma influência política na construção da imagem organizacional das instituições públicas. Foi realizada uma análise com o objetivo de observar como a Universidade, que em 2013 completou sete anos de atividades, está sendo percebida e trabalhada pela imprensa e como se deu a influência do contexto político nos discursos midiáticos. Esse levantamento foi elaborado por meio da análise de conteúdo do clipping impresso e online da instituição, para identificar tendências gerais de interesse da mídia por segmentos e temas. Nesta análise, foi possível verificar uma clara relação entre o número de matérias consideradas negativas e o número de matérias com citações políticas, com referência ao ex-presidente Lula ou ao PT. Os períodos em que a universidade foi abordada pela imprensa por questões como alto índice de evasão e atraso das obras, foram também os períodos em que houve um aumento significativo nas citações político-partidárias. Por fim, foi realizada a análise de discurso em reportagens e artigos selecionados, que confrontaram a imagem trabalhada institucionalmente com a repercutida nos meios de comunicação. Este trabalho possibilitou verificar que nos anos analisados, em especial no ano de 2010, o discurso da organização foi construído mais com o objetivo de reverter a imagem negativa da imprensa do que construir a sua própria imagem.

Chemical modification of a nanocrystalline TiO(2) film for efficient electric connection of glucose oxidase

A novel biosensor for glucose was prepared by adsorption of 1,1`-bis(4-carboxybenzyl)-4,4`-bipyridinium di-bromide compound (H(2)BpybcBr(2)) onto the surface of a nanocrystalline TiO(2) film deposited onto FTO glasses, which was used as a platform to assemble the enzyme glucose oxidase to the electrode surface. The H(2)BpybcBr(2)/TiO(2)/FTO modified electrode was characterized by scanning electron microscopy, X-ray fluorescence image, cyclic voltammograms and spectroelectrochemical measurements. The immobilization of GOD on functionalized TiO(2) film led to stable amperometric biosensing for glucose with a linear range from 153 mu mol L(-1) to 1.30 mmol L(-1) and a detection limit of 51 mu mol L(-1). The apparent Michaelis-Menten constant (K(m)) was estimated to be 3.76 mmol L(-1), which suggested a high enzyme-substrate affinity. The maximum electrode sensitivity was 1.25 mu A mmol L(-1). The study proved that the combination of viologen mediators with TiO(2) film retains the electrocatalytic activity of the enzyme, and also enhances the electron transfer process, and hence regenerating the enzyme in the reaction with glucose. (C) 2010 Elsevier Inc. All rights reserved.

Peat as a natural solid-phase for copper preconcentration and determination in a multicommuted flow system coupled to flame atomic absorption spectrometry

The physical and chemical characteristics of peat were assessed through measurement of pH, percentage of organic matter, cationic exchange capacity (CEC), elemental analysis, infrared spectroscopy and quantitative analysis of metals by ICP OES. Despite the material showed to be very acid in view of the percentage of organic matter, its CEC was significant, showing potential for retention of metal ions. This characteristic was exploited by coupling a peat mini-column to a flow system based on the multicommutation approach for the in-line copper concentration prior to flame atomic absorption spectrometric determination. Cu(II) ions were adsorbed at pH 4.5 and eluted with 0.50 mol L(-1) HNO(3). The influence of chemical and hydrodynamic parameters, such as sample pH, buffer concentration, eluent type and concentration, sample flow-rate and preconcentration time were investigated. Under the optimized conditions, a linear response was observed between 16 and 100 mu g L(-1), with a detection limit estimated as 3 mu g L(-1) at the 99.7% confidence level and an enrichment factor of 16. The relative standard deviation was estimated as 3.3% (n = 20). The mini-column was used for at least 100 sampling cycles without significant variation in the analytical response. Recoveries from copper spiked to lake water or groundwater as well as concentrates used in hemodialysis were in the 97.3-111 % range. The results obtained for copper determination in these samples agreed with those achieved by graphite furnace atomic absorption spectrometry (GFAAS) at the 95% confidence level. (C) 2009 Elsevier B.V. All rights reserved.

PtSnCe/C electrocatalysts for ethanol oxidation: DEFC and FTIR ""in-situ"" studies

The ethanol oxidation reaction (EOR) was investigated using PtSnCe/C electrocatalysts in different mass ratios (72:23:5, 68:22:10 and 64:21:15) that were prepared by the polymeric precursor method. Transmission electron microscopy (TEM) showed that the particles ranged in size from approximately 2 to 5 nm. Changes in the net parameters observed for Pt suggest the incorporation of Sn and Ce into the Pt crystalline network with the formation of an alloy between Pt, Sn and/or Ce. Among the PtSnCe catalysts investigated, the 68:22:10 composition showed the highest activity toward ethanol oxidation, and the current time curves obtained in the presence of ethanol in acidic media showed a current density 50% higher than that observed for commercial PtSn/C (E-Tek). During the experiments performed on single direct ethanol fuel cells, the power density for the PtSnCe/C 68:22:10 anode was nearly 40% higher than the one obtained using the commercial catalyst. Data from Fourier transform infrared (FTIR) spectroscopy showed that the observed behavior for ethanol oxidation may be explained in terms of a double mechanism. The presence of Sn and Ce seems to favor CO oxidation, since they produce an oxygen-containing species to oxidize acetaldehyde to acetic acid. Copyright (C) 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Ethanol oxidation reactions using SnO(2)@Pt/C as an electrocatalyst

This paper presents a study on the ethanol oxidation reaction using SnO(2)@Pt/C core-shell structures as electrocatalysts. All the materials used, including Pt/C and PtSn/C E-tek, were 20% (w/w) metal on carbon. The formation of core-shell nanoparticles (SnO(2)@Pt/C) was measured by UV-vis spectrophotometry. X-ray diffraction measurements showed Pt (shell) diffraction patterns without influence from the SnO(2) core and without any shift in 2 theta values for Pt. The diameters of the core-shell particle structures, measured using high-resolution transmission electron microscopy images, were in the range of 3-16 nm. The electrochemical profile for SnO(2)@Pt/C in an acidic medium (H(2)SO(4) at a concentration of 0.5 mol L(-1)) was almost the same as the typical electrochemical behavior for Pt in an acidic medium. Furthermore, the onset potential for the ethanol oxidation reaction using SnO(2)@Pt/C was almost the same as that for PtSn/C E-tek (0.23 V versus the reversible hydrogen electrode). However, the mass current peak densities for ethanol oxidation were 50% higher on SnO(2)@Pt/C than on PtSn/C E-tek. In the polarization curve, the mass current density for ethanol oxidation was higher at all potentials for SnO(2)@Pt/C when compared to Pt/C and PtSn/C E-tek. At 0.5 V, the current mass density for ethanol oxidation on SnO(2)@Pt was 2.3 times of that for the same process on the commercial material. The electrocatalytic activity of SnO(2)@Pt/C for ethanol oxidation was associated with an increase in the electrochemically active surface area. However, an electronic effect should also be considered because the Pt shell changes its electronic structure in the presence of the foreign core. (C) 2010 Elsevier B.V. All rights reserved.

Study of ethanol electro-oxidation in acid environment on Pt(3)Sn/C anode catalysts prepared by a modified polymeric precursor method under controlled synthesis conditions

A carbon-supported binary Pt(3)Sn catalyst has been prepared using a modified polymeric precursor method under controlled synthesis conditions This material was characterized using X-ray diffraction (XRD). and the results indicate that 23% (of a possible 25%) of Sn is alloyed with Pt, forming a dominant Pt(3)Sn phase. Transmission election microscopy (TEM) shows good dispersion of the electrocatalyst and small particle sizes (3 6 nm +/- 1 nm) The polarization curves for a direct ethanol fuel cell using Pt(3)Sn/C as the anode demonstrated Improved performance compared to that of a PtSn/C E-TEK. especially in the intrinsic resistance-controlled and mass transfer regions. This behavior is probably associated with the Pt(3)Sn phase. The maximum power density for the Pt(3)Sn/C electrocatalyst (58 mW cm(-2)) is nearly twice that of a PtSn/C E-TEK electrocatalyst (33 mW cm(-2)) This behavior is attributed to the presence of a mixed Pt(9)Sn and Pt(3)Sn alloy phase in the commercial catalysts (C) 2009 Elsevier B V All rights reserved

Ethanol oxidation reaction on PtCeO(2)/C electrocatalysts prepared by the polymeric precursor method

This paper presents a study of the electrocatalysis of ethanol oxidation reactions in an acidic medium on Pt-CeO(2)/C (20 wt.% of Pt-CeO(2) on carbon XC-72R), prepared in different mass ratios by the polymeric precursor method. The mass ratios between Pt and CeO(2) (3:1, 2:1, 1:1, 1:2, 1:3) were confirmed by Energy Dispersive X-ray Analysis (EDAX). X-ray diffraction (XRD) structural characterization data shows that the Pt-CeO(2)/C catalysts are composed of nanosized polycrystalline non-alloyed deposits, from which reflections corresponding to the fcc (Pt) and fluorite (CeO(2)) structures were clearly observed. The mean crystallite sizes calculated from XRD data revealed that, independent of the mass ratio, a value close to 3 nm was obtained for the CeO(2) particles. For Pt, the mean crystallite sizes were dependent on the ratio of this metal in the catalysts. Low platinum ratios resulted in small crystallites. and high Pt proportions resulted in larger crystallites. The size distributions of the catalysts particles, determined by XRD, were confirmed by Transmission Electron Microscope (TEM) imaging. Cyclic voltammetry and chronoamperometic experiments were used to evaluate the electrocatalytic performance of the different materials. In all cases, except Pt-CeO(2)/C 1:1, the Pt-Ceo(2)/C catalysts exhibited improved performance when compared with Pt/C. The best result was obtained for the Pt-CeO(2)/C 1:3 catalyst, which gave better results than the Pt-Ru/C (Etek) catalyst. (C) 2009 Elsevier B.V. All rights reserved.

A comparative study of the electrogeneration of hydrogen peroxide using Vulcan and Printex carbon supports

A comparative study of two different conductive carbon-black pigments, Vulcan XC-72 R and Printex L6, for the electrogeneration of hydrogen peroxide (H(2)O(2)) by reducing dissolved oxygen in an alkaline solution was performed. The materials were physically characterized by X-ray diffraction (XRD), Fourier transform infrared attenuated total reflection (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). XRD shows the presence of SO(2) and ATR-FTIR technique indicates a difference in NO and SO(2) functional groups between the two carbon pigments. XPS indicated presence of SO and NO and more oxygenated acid species on Printex L6. A rotating ring-disk electrode was used for electrochemical analysis of the oxygen reduction reaction (ORR). The results showed that the Printex L6 was better than Vulcan XC-72 R for H(2)O(2) production. Results also indicate that the number of electrons transferred in the ORR for Printex L6 and Vulcan XC-72 R were 2.2 and 2.9, respectively, while the percentages of H(2)O(2) formed were 88% and 51%. Scanning electrochemistry microscopy images confirmed the higher amount of H(2)O(2) formed in the Printex L6 pigment. Printex L6 was shown to be a more promising for H(2)O(2) production than Vulcan XC-72 R, while the latter was shown to have more potential for fuel cells. (C) 2011 Elsevier Ltd. All rights reserved.

On the quantumness of correlations in nuclear magnetic resonance

Nuclear magnetic resonance (NMR) was successfully employed to test several protocols and ideas in quantum information science. In most of these implementations, the existence of entanglement was ruled out. This fact introduced concerns and questions about the quantum nature of such bench tests. In this paper, we address some issues related to the non-classical aspects of NMR systems. We discuss some experiments where the quantum aspects of this system are supported by quantum correlations of separable states. Such quantumness, beyond the entanglement-separability paradigm, is revealed via a departure between the quantum and the classical versions of information theory. In this scenario, the concept of quantum discord seems to play an important role. We also present an experimental implementation of an analogue of the single-photon Mach-Zehnder interferometer employing two nuclear spins to encode the interferometric paths. This experiment illustrates how non-classical correlations of separable states may be used to simulate quantum dynamics. The results obtained are completely equivalent to the optical scenario, where entanglement (between two field modes) may be present.

Blocking of Connexin-Mediated Communication Promotes Neuroprotection during Acute Degeneration Induced by Mechanical Trauma

Accruing evidence indicates that connexin (Cx) channels in the gap junctions (GJ) are involved in neurodegeneration after injury. However, studies using KO animal models endowed apparently contradictory results in relation to the role of coupling in neuroprotection. We analyzed the role of Cx-mediated communication in a focal lesion induced by mechanical trauma of the retina, a model that allows spatial and temporal definition of the lesion with high reproducibility, permitting visualization of the focus, penumbra and adjacent areas. Cx36 and Cx43 exhibited distinct gene expression and protein levels throughout the neurodegeneration progress. Cx36 was observed close to TUNEL-positive nuclei, revealing the presence of this protein surrounding apoptotic cells. The functional role of cell coupling was assessed employing GJ blockers and openers combined with lactate dehydrogenase (LDH) assay, a direct method for evaluating cell death/viability. Carbenoxolone (CBX), a broad-spectrum GJ blocker, reduced LDH release after 4 hours, whereas quinine, a Cx36-channel specific blocker, decreased LDH release as early as 1 hour after lesion. Furthermore, analysis of dying cell distribution confirmed that the use of GJ blockers reduced apoptosis spread. Accordingly, blockade of GJ communication during neurodegeneration with quinine, but not CBX, caused downregulation of initial and effector caspases. To summarize, we observed specific changes in Cx gene expression and protein distribution during the progress of retinal degeneration, indicating the participation of these elements in acute neurodegeneration processes. More importantly, our results revealed that direct control of GJ channels permeability may take part in reliable neuroprotection strategies aimed to rapid, fast treatment of mechanical trauma in the retina.

Low-energy electron collisions with glycine

We report cross sections for elastic electron scattering by gas phase glycine (neutral form), obtained with the Schwinger multichannel method. The present results are the first obtained with a new implementation that combines parallelization with OpenMP directives and pseudopotentials. The position of the well known pi* shape resonance ranged from 2.3 eV to 2.8 eV depending on the polarization model and conformer. For the most stable isomer, the present result (2.4 eV) is in fair agreement with electron transmission spectroscopy assignments (1.93 +/- 0.05 eV) and available calculations. Our results also point out a shape resonance around 9.5 eV in the A' symmetry that would be weakly coupled to vibrations of the hydroxyl group. Since electron attachment to a broad and lower lying sigma* orbital located on the OH bond has been suggested the underlying mechanism leading to dissociative electron attachment at low energies, we sought for a shape resonance around similar to 4 eV. Though we obtained cross sections with the target molecule at the equilibrium geometry and with stretched OH bond lengths, least-squares fits to the calculated eigenphase sums did not point out signatures of this anion state (though, in principle, it could be hidden in the large background). The low energy (similar to 1 eV) integral cross section strongly scales as the bond length is stretched, and this could indicate a virtual state pole, since dipole supported bound states are not expected at the geometries addressed here. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3687345]

Effects of catalyst load in Pt and Pb-based catalysts using formic acid oxidation as a model

In this paper, we discuss the effects of catalyst load with respect to carbon powder for several Pt and Pb-based catalysts, using formic acid as a model molecule. The discussion is based on electrochemical tests, a complete morphological investigation and theoretical calculations. We show that the Pt and Pb-based catalysts presented activity in formic acid oxidation at very low catalyst loads (e.g., 0.5% in respect to the carbon content). Physical characterisations demonstrate that the electrodes are composed of separated phases of Pt and lead distributed in Pt nanometric-sized islands that are heterogeneously dispersed on the carbon support and Pb ultra-small particles homogeneously distributed throughout the entire carbon surface, as demonstrated by the microscopy studies. At high catalyst loads, very large clusters of Pb(x)O(y) could be observed. Electrochemical tests indicated an increase in the apparent resistance of the system (by a factor of 19.7 Omega) when the catalyst load was increased. The effect of lead in the materials was also studied by theoretical calculations (OFT). The main conclusion is that the presence of Pb atoms in the catalyst can improve the adsorption of formic acid in the catalytic system compared with a pure Pt-based catalyst. (C) 2011 Elsevier B.V. All rights reserved.

Flow injection analysis of free glycerol in biodiesel using a copper electrode as an amperometric detector

The main goal of this work was to develop a simple analytical method for quantification of glycerol based on the electrocatalytic oxidation of glycerol on the copper surface adapted in a flow injection system. Under optimal experimental conditions, the peak current response increases linearly with glycerol concentration over the range 60-3200 mg kg(-1) (equivalent to 3-160 mg L(-1) in solution). The repeatability of the electrode response in the flow injection analysis (FIA) configuration was evaluated as 5% (n = 10), and the detection limit of the method was estimated to be 5 mg kg(-1) in biodiesel (equivalent to 250 mu g L(-1) in solution) (S/N = 3). The sample throughput under optimised conditions was estimated to be 90 h(-1). Different types of biodiesel samples (B100), as in the types of vegetable oils or animal fats used to produce the fuels, were analysed (seven samples). The only sample pre-treatment used was an extraction of glycerol from the biodiesel sample containing a ratio of 5 mL of water to 250 mg of biodiesel. The proposed method improves the analytical parameters obtained by other electroanalytical methods for quantification of glycerol in biodiesel samples, and its accuracy was evaluated using a spike-and-recovery assay, where all the biodiesel samples used obtained admissible values according to the Association of Official Analytical Chemists. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.

Natural rubber latex LbL films: Characterization and growth of fibroblasts

The recent biomedical applications of natural rubber (NR) latex, mostly in dry membranes, have motivated research into novel, more noble uses of this low-cost biomaterial. In this article, we provide the first report on the fabrication of layer-by-layer (LbL) films of NR alternated with the polyelectrolytes polyethylenimine (PEI) and polyallylamine hydrochloride (PAH). Stable (PAH/NR)n and (PEI/NR)n LbL films displayed similar physicochemical properties, but differed in terms of film morphology according to atomic force microscopy (AFM) and scanning electron microscopy (SEM) data. Most significantly, (PEI/NR)5 LbL films were made of smaller and flattened particles, which were not efficient for the growth and proliferation of normal human fibroblasts (NHF). In contrast, efficient NHF proliferation could be obtained with (PAH/NR)n LbL films, with the fibroblasts exhibiting the expected elongated morphology. Furthermore, cell growth did not occur for cast films of NR, thus demonstrating the suitability of the LbL method for this biologically related application. The differences between the two polyelectrolytes illustrate the importance of the film architecture and morphology, which open the way for exploiting the molecular control inherent in the LbL technique for further applications of NR-containing films. (c) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012