Natal, Brazil

The Federal University of Rio Grande do Norte is a public Brazilian university funded by the Brazilian federal government, located in the city of Natal, Rio Grande do Norte, Brazil.Formally established on December 18, 1960, it includes 60 departments providing over 70 different undergraduate courses, as well as a number of graduate programs.UFRN is the top ranked university in the state of Rio Grande do Norte, and one of the best among universities from all over the country according to 2012 league tables. Wikipedia.

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Martinez-Huitle C.A.,Federal University of Rio Grande do Norte | Rodrigo M.A.,University of Castilla - La Mancha | Sires I.,University of Barcelona | Scialdone O.,University of Palermo
Chemical Reviews | Year: 2015

Traditional physicochemical and biological techniques, as well as advanced oxidation processes (AOPs), are often inadequate, ineffective, or expensive for industrial water reclamation. Within this context, the electrochemical technologies have found a niche where they can become dominant in the near future, especially for the abatement of biorefractory substances. In this critical review, some of the most promising electrochemical tools for the treatment of wastewater contaminated by organic pollutants are discussed in detail with the following goals: (1) to present the fundamental aspects of the selected processes; (2) to discuss the effect of both the main operating parameters and the reactor design on their performance; (3) to critically evaluate their advantages and disadvantages; and (4) to forecast the prospect of their utilization on an applicable scale by identifying the key points to be further investigated. The review is focused on the direct electrochemical oxidation, the indirect electrochemical oxidation mediated by electrogenerated active chlorine, and the coupling between anodic and cathodic processes. The last part of the review is devoted to the critical assessment of the reactors that can be used to put these technologies into practice. © 2015 American Chemical Society.

Brillas E.,University of Barcelona | Martinez-Huitle C.A.,Federal University of Rio Grande do Norte
Applied Catalysis B: Environmental | Year: 2015

As the environment preservation gradually becomes a matter of major social concern and more strict legislation is being imposed on effluent discharge, more effective processes are required to deal with non-readily biodegradable and toxic pollutants. Synthetic organic dyes in industrial effluents cannot be destroyed in conventional wastewater treatment and consequently, an urgent challenge is the development of new environmentally benign technologies able to mineralize completely these non-biodegradable compounds. This review aims to increase the knowledge on the electrochemical methods used at lab and pilot plant scale to decontaminate synthetic and real effluents containing dyes, considering the period from 2009 to 2013, as an update of our previous review up to 2008. Fundamentals and main applications of electrochemical advanced oxidation processes and the other electrochemical approaches are described. Typical methods such as electrocoagulation, electrochemical reduction, electrochemical oxidation and indirect electro-oxidation with active chlorine species are discussed. Recent advances on electrocatalysis related to the nature of anode material to generate strong heterogeneous OH as mediated oxidant of dyes in electrochemical oxidation are extensively examined. The fast destruction of dyestuffs mediated with electrogenerated active chlorine is analyzed. Electro-Fenton and photo-assisted electrochemical methods like photoelectrocatalysis and photoelectro-Fenton, which destroy dyes by heterogeneous OH and/or homogeneous OH produced in the solution bulk, are described. Current advantages of the exposition of effluents to sunlight in the emerging photo-assisted procedures of solar photoelectrocatalysis and solar photoelectro-Fenton are detailed. The characteristics of novel combined methods involving photocatalysis, adsorption, nanofiltration, microwaves and ultrasounds among others and the use of microbial fuel cells are finally discussed. © 2014 Elsevier B.V.

Gavioli E.C.,Federal University of Rio Grande do Norte | Calo' G.,University of Ferrara
Pharmacology and Therapeutics | Year: 2013

Nociceptin/orphanin FQ (N/OFQ) and its receptor (NOP) were identified in the mid 90s as a novel peptidergic system structurally related to opioids. A growing body of preclinical evidence suggests that blockade of NOP receptors evokes antidepressant-like actions. These have been explored using a range of compounds (peptide and non peptide antagonists), across different species (rat and mouse) and assays (behavioral despair and chronic mild stress) suggesting a robust and consistent antidepressant-like effect. Moreover, rats and mice knockout for the NOP receptor gene display an antidepressant-like phenotype in behavioral despair assays. Electrophysiological, immunohistochemical and neurochemical studies point to an important role played by monoaminergic systems, particularly 5-HTergic, in mediating the antidepressant-like properties of NOP antagonists. However other putative mechanisms of action, including modulation of the CRF system, circadian rhythm and a possible neuroendocrine-immune control might be involved. A close relationship between the N/OFQ-NOP receptor system and stress responses is well described in the literature. Stressful situations also alter endocrine, behavioral and neurochemical parameters in rats and chronic administration of a NOP antagonist restored these alterations. Interestingly, clinical findings showed that plasma N/OFQ levels were significantly altered in major and post-partum depression, and bipolar disease patients. Collectively, data in the literature support the notion that blockade of NOP receptor signaling could be a novel and interesting strategy for the development of innovative antidepressants. © 2013 Elsevier Inc.

Fichet S.,Federal University of Rio Grande do Norte
Nuclear Physics B | Year: 2014

We present a technique to determine the scale of New Physics (NP) compatible with any set of data, relying on well-defined credibility intervals. Our approach relies on the statistical view of the effective field theory capturing New Physics at low energy. We introduce formally the notion of testable NP and show that it ensures integrability of the posterior distribution. We apply our method to the Standard Model Higgs sector in light of recent LHC data, considering two generic scenarios. In the scenario of democratic higher-dimensional operators generated at one-loop, we find the testable NP scale to lie within [10, 260] TeV at 95% Bayesian credibility level. In the scenario of loop-suppressed field strength-Higgs operators, the testable NP scale is within [28, 1200] TeV at 95% Bayesian credibility level. More specific UV models are necessary to allow lower values of the NP scale. © 2014 The Author.

Freitas D.A.,Federal University of Rio Grande do Norte
The Cochrane database of systematic reviews | Year: 2013

Breathing exercises have been widely used worldwide as a complementary therapy to the pharmacological treatment of people with asthma. To evaluate the evidence for the efficacy of breathing exercises in the management of patients with asthma. The search for trials led review authors to review the literature available in The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL and AMED and to perform handsearching of respiratory journals and meeting abstracts. Trial registers and reference lists of included articles were also consulted.The literature search has been updated to January 2013. We included randomised controlled trials of breathing exercises in adults with asthma compared with a control group receiving asthma education or, alternatively, with no active control group. Two review authors independently assessed trial quality and extracted data. RevMan software was used for data analysis based on the fixed-effect model. Continuous outcomes were expressed as mean differences (MDs) with confidence intervals (CIs) of 95%. Heterogeneity was assessed by inspecting the forest plots. The Chi(2) test was applied, with a P value of 0.10 indicating statistical significance. The I(2) statistic was implemented, with a value greater than 50% representing a substantial level of heterogeneity. A total of 13 studies involving 906 participants are included in the review. The trials were different from one another in terms of type of breathing exercise performed, number of participants enrolled, number and duration of sessions completed, outcomes reported and statistical presentation of data. Asthma severity in participants from the included studies ranged from mild to moderate, and the samples consisted solely of outpatients. The following outcomes were measured: quality of life, asthma symptoms, number of acute exacerbations and lung function. Eleven studies compared breathing exercise with inactive control, and two with asthma education control groups. All eight studies that assessed quality of life reported an improvement in this outcome. An improvement in the number of acute exacerbations was observed by the only study that assessed this outcome. Six of seven included studies showed significant differences favouring breathing exercises for asthma symptoms. Effects on lung function were more variable, with no difference reported in five of the eleven studies that assessed this outcome, while the other six showed a significant difference for this outcome, which favoured breathing exercises. As a result of substantial heterogeneity among the studies, meta-analysis was possible only for asthma symptoms and changes in the Asthma Quality of Life Questionnaire (AQLQ). Each meta-analysis included only two studies and showed a significant difference favouring breathing exercises (MD -3.22, 95% CI -6.31 to -0.13 for asthma symptoms; MD 0.79, 95% CI 0.50 to 1.08 for change in AQLQ). Assessment of risk of bias was impaired by incomplete reporting of methodological aspects of most of the included trials. Even though individual trials reported positive effects of breathing exercises, no reliable conclusions could be drawn concerning the use of breathing exercises for asthma in clinical practice. This was a result of methodological differences among the included studies and poor reporting of methodological aspects in most of the included studies. However, trends for improvement are encouraging, and further studies including full descriptions of treatment methods and outcome measurements are required.

de Lima K.M.G.,Federal University of Rio Grande do Norte
Microchemical Journal | Year: 2012

The present work describes a portable photometer based on light-emitting-diodes (LED) for the determination of total aromatic hydrocarbons in water contaminated with gasoline. Two LED were employed as the light source with maximum emission at 1300nm and 1689nm. The radiation of each LED was collected with bundles of 24 silica optical fibers, which were assembled in a single bundle pointed toward the detection cell. An InGaAs photodiode was directly connected to the measuring cell. Software was written in VisualBasic.NET to control the photometer through a USB interface and for data acquisition. The determination of total aromatic hydrocarbons was performed using a silicone-sensing phase (length of 5mm and diameter of 3.2mm), which was employed to extract these compounds from the contaminated water. The extraction (60min under constant stirring) was performed in a 100-mL flask filled with the water sample diluted in 2.0molL -1 NaCl. A repeatability of 1.8% and 1.3% (expressed as the relative standard deviation of 10 measurements) was obtained at 1300nm and 1689nm, respectively. Absorbance values were calculated considering the signal at 1300nm as reference because hydrocarbons do not absorb at this wavelength. Analytical curves up to 200mgL -1 and 400mgL -1 were constructed for benzene and toluene, providing limits of detection of 1.2mgL -1 and 1.7mgL -1, respectively. The sensitivity was similar to those obtained with a FT-NIR Bomem MB 160 spectrophotometer at the same wavelength. The photometer was applied to the determination of total hydrocarbons in water contaminated by gasoline. An analytical curve (50-300mgL -1) was constructed from reference solutions containing benzene and toluene in the ratio of 3:7, which is a ratio commonly found in Brazilian gasoline. The results provided by the photometer were compared with those obtained with the commercial spectrophotometer and did not show significant differences at a confidence level of 95%. © 2011 Elsevier B.V..

Lehum A.C.,Federal University of Rio Grande do Norte
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

Using the superfield formalism and implementing the canonical noncommutativity, the Kählerian effective superpotential is evaluated in the three-dimensional noncommutative supersymmetric Chern-Simons-matter model at the two-loop order. The computation of the Kählerian effective superpotential is enough to determine whether the model can exhibit spontaneous (super)symmetry breaking. It is shown that the model possesses a spontaneous gauge symmetry broken phase, generating masses for the scalar and gauge superfields at the two-loop order. Just as for the commutative version, in the noncommutative case, the supersymmetry cannot be broken by radiative corrections via the Coleman-Weinberg mechanism. © 2012 American Physical Society.

Ribeiro S.,Federal University of Rio Grande do Norte
Pflugers Archiv European Journal of Physiology | Year: 2012

While there is ample agreement that the cognitive role of sleep is explained by sleep-dependent synaptic changes, consensus is yet to be established as to the nature of these changes. Some researchers believe that sleep promotes global synaptic downscaling, leading to a non-Hebbian reset of synaptic weights that is putatively necessary for the acquisition of new memories during ensuing waking. Other investigators propose that sleep also triggers experience-dependent, Hebbian synaptic upscaling able to consolidate recently acquired memories. Here, I review the molecular and physiological evidence supporting these views, with an emphasis on the calcium signaling pathway. I argue that the available data are consistent with sleep promoting experience-dependent synaptic embossing, understood as the simultaneous non-Hebbian downscaling and Hebbian upscaling of separate but complementary sets of synapses, heterogeneously activated at the time of memory encoding and therefore differentially affected by sleep. © 2011 The Author(s).

Bedregal B.C.,Federal University of Rio Grande do Norte
Fuzzy Sets and Systems | Year: 2010

There exist infinitely many ways to extend the classical propositional connectives to the set [0,1], preserving their behaviors in the extremes 0 and 1 exactly as in the classical logic. However, it is a consensus that this issue is not sufficient, and, therefore, these extensions must also preserve some minimal logical properties of the classical connectives. The notions of t-norms, t-conorms, fuzzy negations and fuzzy implications taking these considerations into account. In previous works, the author, joint with other colleagues, generalizes these notions to the set U={[a,b]0≤a≤b≤1, providing canonical constructions to obtain, for example, interval t-norms that are the best interval representations of t-norms. In this paper, we consider the notion of interval fuzzy negation and generalize, in a natural way, several notions related with fuzzy negations, such as the ones of equilibrium point and negation-preserving automorphism. We show that the main properties of these notions are preserved in those generalizations. © 2010 Elsevier B.V. All rights reserved.

Batista R.C.,Federal University of Rio Grande do Norte
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

We show that in clustering dark energy models the growth index of linear matter perturbations, γ, can be much lower than in ΛCDM or smooth quintessence models and presents a strong variation with redshift. We find that the impact of dark energy perturbations on γ is enhanced if the dark energy equation of state has a large and rapid decay at low redshift. We study four different models with these features and show that we may have 0.33<γ(z)<0.48 at 0

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