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Porto Alegre, Brazil

The Federal University of Rio Grande do Sul is one of the largest federal universities in Brazil. It is almost completely located in Porto Alegre, with four campuses , some isolated buildings and some isolated units in other cities. UFRGS is among the best Brazilian universities, and has one of the greatest numbers of scientific publications. UFRGS has over 27,000 undergraduate students and over 9,300 graduate students. The university has more than 2,500 professors. As a public federal institution, the students do not have to pay tuition fees to enroll in the courses offered by the university. To be admitted to one of the courses offered by UFRGS, a candidate must be approved in a yearly competitive exam, called the vestibular.The institute also has a profound political history. Between 1964 and 1969, during the worst years of the military dictatorship, 33 professors were eliminated, as well as a good number of students. The experience echoes a tradition of social commitment and combativeness.The institute has since been active not only in forming new generations of students, but also in the production of knowledge through high-quality research and consultancies. Today, many of the high-ranking officials in government as well as the majority of the history, philosophy and social science teachers in smaller universities throughout the state were educated in the institution.The climate of intellectual debate and analysis of public issues has also been important in training students to work for non-governmental and governmental organisations which contribute to the critical reflection and planning of development programs. Among the graduates of UFRGS, there are three Brazilian presidents: Getúlio Vargas, João Goulart, and Dilma Rousseff. Wikipedia.

Padilha D.L.,Federal University of Goais | Loregian A.C.,Federal University of Rio Grande do Sul | Budke J.C.,URI Integrated Regional University Brazil
Biodiversity and Conservation | Year: 2015

Testing whether biological invasions can be facilitated by habitat fragmentation can provide important insights for the study of invasion ecology. Hovenia dulcis is considered an aggressive non-native species in subtropical Atlantic forest ecosystems and following the assumptions of invasion ecology we hypothesized it would occur mainly in smaller forest remnants, which are more susceptible to edge effects compared to larger ones. In this study, we verified the relationships between H. dulcis invasion on forest remnants and the current habitat fragmentation and tested whether both occurrence and abundance of this species are driven by landscape and habitat variables. We selected 30 forest fragments in initial, middle or late successional stages and verified the occurrence and abundance of trees and saplings of H. dulcis. We evaluated spatial autocorrelation and the influence of landscape and habitat metrics on occurrence and abundance of such species and the influence of fruiting trees (adults) on the abundance of non-adult individuals. We found that H. dulcis distribution was not related to geographic distance among remnants. The occurrence of adult H. dulcis was directly associated to closed-canopy areas and remnant shape and, contrary our initial hypothesis, not related to remnant size. The occurrence of adult trees increased H. dulcis regeneration leading to higher sapling abundance. High abundance of H. dulcis saplings close to adult trees pointed out the successful colonization of recently invaded Atlantic forest remnants. We showed that this invasive tree species successfully invades closed-canopy forest fragments, which highlight undisturbed subtropical Atlantic forest habitats are as susceptible to biological invasions as disturbed ones. © 2015, Springer Science+Business Media Dordrecht.

Muniz A.R.,Federal University of Rio Grande do Sul | Fonseca A.F.,University of Campinas
Journal of Physical Chemistry C | Year: 2015

Low or zero thermal expansion (ZTE) materials are suitable for applications requiring low dimensional changes under large temperature variations. Using density functional theory calculations and classical molecular dynamics simulations, we demonstrate that tailoring the density of covalent carbon-carbon interlayer bonds in bilayer graphene tunes its thermal expansion coefficient from negative to positive values at room temperature and, most exciting, causes it to exhibit ZTE behavior in a wide range of temperatures. © 2015 American Chemical Society.

de Slavutzky S.M.B.,Federal University of Rio Grande do Sul
Journal fur Verbraucherschutz und Lebensmittelsicherheit | Year: 2010

An in vivo study was done by measuring the accumulation of dental plaque after rinsing with a solution of 10% sucrose four times daily during 5 days and comparing it with a rinsing of 10% solution of Stevia rebaudiana Bertoni four times a day, during 5 days a week. The accumulation of dental plaque after rinsing with Stevia was 57, 82% less than under rinsing with sucrose as measured by the Silness-Löe index and 10, 40% less plaque when measured by O'Leary index of plaque. © Birkhäuser Verlag, Basel/Switzerland 2010.

Rizzotto G.J.,Geological Survey of Brazil CPRM | Hartmann L.A.,Federal University of Rio Grande do Sul
Lithos | Year: 2012

We document the first-known Mesoproterozoic ophiolite from the southwestern part of the Amazon craton, corresponding to the Trincheira Complex of Calymmian age, and propose a tectonic model that explains many previously enigmatic features of the Precambrian history of this key craton, and discuss its role in the reconstruction of the Columbia supercontinent. The complex comprises extrusive rocks (fine-grained amphibolites derived from massive and pillowed basalts), mafic-ultramafic intrusive rocks, chert, banded iron formation (BIFs), pelites, psammitic and a smaller proportion of calc-silicate rocks. This sequence was deformed, metasomatized and metamorphosed during the development of the Alto Guaporé Belt, a Mesoproterozoic accretionary orogen. The rocks were deformed by a single tectonic event, which included isoclinal folding and metamorphism of the granulite-amphibolite facies. Layered magmatic structures were preserved in areas of low strain, including amygdaloidal and cumulate structures. Metamorphism was pervasive and reached temperatures of 780-853 °C in mafic granulites and 680-720 °C in amphibolites under an overall pressure of 6.8. kbar. The geochemical composition of the extrusive and intrusive rocks indicates that all noncumulus mafic-ultramafic rocks are tholeiitic basalts. The mafic-ultramafic rocks display moderate to strong fractionation of light rare earth elements (LREE), near-flat heavy rare earth element (HREE) patterns and moderate to strong negative high field strength element (HFSE) anomalies (especially Nb), a geochemical signature typical of subduction zones. The lowest units of mafic granulites and porphyroblastic amphibolites in the Trincheira ophiolite are similar to the modern mid-ocean ridge basalt (MORB), although they locally display small Ta, Ti and Nb negative anomalies, indicating a small subduction influence. This behavior changes to an island arc tholeiite (IAT) signature in the upper units of fine-grained amphibolites and amphibole rich-amphibolites, characterized by progressive depletion in the incompatible elements and more pronounced negative Ta and Nb anomalies, as well as common Ti and Zr negative anomalies. Tectono-magmatic variation diagrams and chondrite-normalized REE and primitive mantle normalized patterns suggest a back-arc to intra-oceanic island arc tectonic regime for the eruption of these rocks. Therefore, the Trincheira ophiolite appears to have originated in an intraoceanic supra-subduction setting composed of an arc-back-arc system. Accordingly, the Trincheira Complex is a record of oceanic crust relics obducted during the collision of the Amazon craton and the Paraguá block during the Middle Mesoproterozoic. Thus, the recognition of the Trincheira ophiolite and suture significantly changes views on the evolution of the southern margin of the Amazon craton, and how it can influence the global tectonics and the reconstruction of the continents. © 2012 Elsevier B.V.

Pinto V.M.,Federal University of Roraima | Hartmann L.A.,Federal University of Rio Grande do Sul | Santos J.O.S.,University of Western Australia | McNaughton N.J.,Curtin University Australia | Wildner W.,Companhia de Pesquisa de Recursos Minerais
Chemical Geology | Year: 2011

Ion microprobe U-Pb isotopic data on zircons from the Paraná magmatic province are presented from one tholeiitic (high-Ti Pitanga type) and three felsic volcanic rocks from the low-Ti Palmas and high-Ti Chapecó types. Igneous zircons from the four volcanic rocks yield volcanism ages within error: i.e. 134.4 ± 1.1. Ma (basalt), 134.6 ± 1.4. Ma (rhyodacite), 134.8 ± 1.4 (quartz latite) and 135.6 ± 1.8. Ma (quartz latite). The age of Paraná magmatism based on previous Ar-Ar geochronology has two divergent ranges: 1) 1 to 2. million years with magmatic peak at 131-133. Ma, and 2) over ~. 10. m.y. between 137 and 127. Ma. Our results show that the bimodal volcanics of the province, at least to the south of the Piquiri lineament, have very high effusion rates over a brief period with a main pulse at ~. 135. Ma, about 2% older than proposal 1, more akin to a short period of magmatism. These results are most significant for the understanding of time relations in this large intraplate magmatic province. © 2010 Elsevier B.V.

Levin Y.,Federal University of Rio Grande do Sul | Dos Santos A.P.,Federal University of Santa Catarina
Journal of Physics Condensed Matter | Year: 2014

We review the present understanding of the behavior of ions at the air-water and oil-water interfaces. We argue that while the alkali metal cations remain strongly hydrated and are repelled from the hydrophobic surfaces, the anions must be classified into kosmotropes and chaotropes. The kosmotropes remain strongly hydrated in the vicinity of a hydrophobic surface, while the chaotropes lose their hydration shell and can become adsorbed to the interface. The mechanism of adsorption is still a subject of debate. Here, we argue that there are two driving forces for anionic adsorption: the hydrophobic cavitational energy and the interfacial electrostatic surface potential of water. While the cavitational contribution to ionic adsorption is now well accepted, the role of the electrostatic surface potential is much less clear. The difficulty is that even the sign of this potential is a subject of debate, with the ab initio and the classical force field simulations predicting electrostatic surface potentials of opposite sign. In this paper, we will argue that the strong anionic adsorption found in the polarizable force field simulations is the result of the artificial electrostatic surface potential present in the classical water models. We will show that if the adsorption of anions were as large as predicted by the polarizable force field simulations, the excess surface tension of the NaI solution would be strongly negative, contrary to the experimental measurements. While the large polarizability of heavy halides is a fundamental property and must be included in realistic modeling of the electrolyte solutions, we argue that the point charge water models, studied so far, are incompatible with the polarizable ionic force fields when the translational symmetry is broken. The goal for the future should be the development of water models with very low electrostatic surface potential. We believe that such water models will be compatible with the polarizable force fields, which can then be used to study the interaction of ions with hydrophobic surfaces and proteins. © 2014 IOP Publishing Ltd.

Objective: The aim of this study was to confirm, in a sample of young adults from the general population, recent findings regarding the pathophysiology of bipolar disorder. The focus of this investigation was finding group differences in one neurotrophin, two markers of oxidative damage, two proinflammatory cytokines and one anti-inflammatory cytokine in participants with bipolar disorder, major depression and people without any mood episodes. Markers assessed here were brain-derived neurotrophic factor (BDNF), thiobarbituric acid reactive substances (TBARS), protein carbonyl content (PCC), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-10 (IL-10). Method: Individuals from the general population, previously included in a cross-sectional study (n=1560), with a positive screen for bipolar disorder were recruited, as well as two groups of controls. One had only depressive episodes and the other had no history of mood episodes. This yielded a sample of 231 participants that further underwent diagnostic confirmation with the Structured Clinical Interview for DSM-IV (SCID). All analyses included a check for bivariate associations, as well as an a priori multivariate model with sex, social class, current mood state, use of substances and SCID diagnoses as predictors. Results: The final sample included 55 participants with bipolar disorder, 82 with major depression and 94 healthy controls. Only a minority was using any psychiatric medications (9.6%). Bipolar disorder was associated with higher PCC and TNF-α levels when compared to the control group. Major depression was also associated with higher PCC levels when compared to the control condition. Use of psychiatric medication was associated with lower TNF-α levels. Correlations between the same markers were not as strong as in clinical samples. Conclusions: Two broad conclusions are called for from these results. The first is that early-stage bipolar disorder is already associated with a pro-oxidant, proinflammatory state. The second is that these changes appear more subtle than those observed in typical late-stage, chronic patients, supporting the notion that a form of illness progression takes place. The main caveat is that these data are cross-sectional, not longitudinal, which precludes causal inferences as factors other than the bipolar illness can conceivably induce systemic toxicity.

Reiss M.L.L.,Federal University of Rio Grande do Sul | Tommaselli .A.M.G.,Paulista University
Photogrammetric Record | Year: 2011

The purpose of this work is to present the main features of a structured light system and some experimental results. The system, named SingleShot3DSL, is based on a single off-the-shelf digital camera and a pattern projector. The mathematical model for 3D reconstruction is based on the collinearity equations. A pattern codification strategy was developed to allow fully automatic pattern recognition. A calibration methodology enables the determination of the direction vector of each pattern and the coordinates of the perspective centre of the pattern projector. The calibration processes are carried out with the acquisition of several images of a plane taken from different distances and orientations. Several processes were combined to provide a reliable solution for pattern location. In order to assess the accuracy and potential of the methodology a prototype was built, integrating a pattern projector and a digital camera in a single mount. Experiments using reconstructed surfaces with real data indicated that a relative accuracy of 0·2mm in depth could be achieved. © 2011 The Authors. The Photogrammetric Record © 2011 The Remote Sensing and Photogrammetry Society and Blackwell Publishing Ltd.

Scott J.,Northumbria University | Scott J.,University Paris Est Creteil | Leboyer M.,University Paris Est Creteil | Hickie I.,University of Sydney | And 5 more authors.
British Journal of Psychiatry | Year: 2013

Staging models are used routinely in general medicine for potentially serious or chronic physical disorders such as diabetes, arthritis and cancers, describing the links between biomarkers, clinical phenotypes and disease extension, and promoting a personalised or stratified medicine approach to treatment planning. Clinical staging involves a detailed description of where an individual exists on a continuum of disorder progression from stage 0 (an at-risk or latency stage) through to stage IV (late or end-stage disease). The approach is popular owing to its clinical utility and is increasingly being applied in psychiatry. The concept offers an informed approach to research and the active promotion of indicated prevention and early intervention strategies. We suggest that for young persons with emerging bipolar disorder, such transdiagnostic staging models could provide a framework that better reflects the developmental psychopathology and matches the complex longitudinal interrelationships between subsyndromal and syndromal mood, psychotic and other disorders.

Gazolla M.,Federal University of Santa Maria | Schneider S.,Federal University of Rio Grande do Sul
Revista de Economia e Sociologia Rural | Year: 2013

This article aims to study the National Programme for Strengthening Family Agriculture (Pronaf) in their credit lines for costing and investment, in order to investigate their relationships and interfaces with the family farm, using it for a study in Rio Grande do Sul (Middle High Uruguay microregion). The question to be answered is: what kind of building that is generating Pronaf with family farmers? To do this, it was used a methodology based on qualitative, using semi-structured interviews and underpinned by arguments with secondary data from various sources and research. It is concluded that the program has a dual logic. On the one hand, it is financing production activities usual for farmers, such as grain and agricultural commodities. On the other hand, there is a process of economic diversification of productive activities, small livestock, crops and basic food for household consumption.

Umpierre A.P.,University of Brasilia | deJesus E.,University of Alcala | Dupont J.,Federal University of Rio Grande do Sul
ChemCatChem | Year: 2011

The catalytic activity expressed by turnover number (TON) and turnover frequency (TOF) in different fields of catalysis (enzymatic, homogeneous (single-site), heterogeneous (multi-site), and nanocatalysis (oligo-site)) are usually estimated in slightly different ways and with slightly different, yet important meanings. For soluble metal nanoparticles, the ideal is to determine the TON by using the titrated number of active catalytic sites before the catalyst is inactivated. However, in the absence of reliable titration methods it is suggested that TON figures should always be reported as the number of moles of reactants consumed per mol of soluble metal catalyst, and that they should also be corrected by the number of exposed surface atoms by using the metal atom's magic number approach. Moreover, it is strongly recommended that the TOF should be determined from the slope of plots of turnover numbers versus time, because in various cases the size and shape of the soluble nanoparticles might change dramatically during the reaction. As in organometallic catalysis, in the absence of TON vs. time data, the TOF should be estimated for low substrate conversions. Defects beat faces: It is proposed that, for soluble metal nanoparticles, ideally the turnover number (TON) is determined by using the titrated number of active catalytic sites. However, in the absence of reliable titration methods, the TON figures should be reported as the number of moles of reactants consumed per mol of soluble metal nanoparticle and the figures should also be corrected by the number of exposed surface atoms by using the metal atom's magic number approach. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

When 'fingerprinting' is used to identify what proportions Ps (s=1,..., g) of suspended sediment come from g different source areas, measures of the uncertainties in estimates of the Ps are also required. These uncertainties are influenced by two kinds of correlation whose effects are rarely recognized in the literature. These are (i) correlation between the estimated Ps because they must add to 1 and (ii) correlation between the geochemical tracers measured in sediment samples. This paper uses bootstrap procedures to identify joint confidence regions for the estimated proportions [responding to correlation of type (i)] and to explore alternatives to the 'standard' least-squares criterion used to estimate the proportions when tracer measurements are correlated [correlation of type (ii)]. Using a limited dataset with three sediment source areas for illustration (g=3), results were obtained from 5000 bootstrap samples, using two criteria (standard and generalized least squares, GLS) with two inequality constraints: (a) 0≤Ps≤1, where Ps is the fraction of suspended sediment contributed by the s-th source area (s=1, 2, 3) and (b) 0s<1, which, the paper argues, better represents reality. Approximate 95% confidence regions for the Ps, given by the two criteria and two inequality constraints, were compared. Using inequality constraint (a), the confidence region given by the GLS criterion was slightly smaller than that given by the standard; using constraint (b), the two confidence regions' boundaries were almost identical, suggesting that the effects of correlations between tracers were not large for the dataset used. For both criteria, the scatter amongst estimated proportions Ps obtained by bootstrapping was large, raising issues concerning the efficiency of sampling and the allocation of sampling effort, both in source areas and in transported suspended sediment. The results suggest that apparently small differences in the constraints applied to the proportions Ps can give quite different numerical results. © 2014 John Wiley & Sons, Ltd.

Schneck F.,Federal University of Rio Grande do Sul | Melo A.S.,Federal University of Goais
Freshwater Biology | Year: 2012

Habitat heterogeneity in lotic systems is usually associated with the availability of refuges. Heterogeneous habitats (here, rough substrata) should mediate the effect of high-flow disturbances by protecting benthic algae, thus increasing the resistance and resilience of the system. Additionally, the ability of algae to resist a disturbance and recover after it should be dependent on biological traits that confer resistance and resilience. We designed a field experiment, simulating a high-flow event with bed movement, to test the effect of substratum roughness on the resistance (assessed as the similarity between samples collected before and immediately after disturbance) and resilience (the similarity between samples collected before and 7 and 15days after disturbance) of five algal life forms. We evaluated whether algal resistance and resilience were higher on rough than on smooth substrata, and whether the life forms differed in their ability to resist and recover from a disturbance. Rough substrata had higher species richness than smooth substrata at all sampling periods, even immediately after the disturbance. There was no significant effect of substratum roughness on algal resistance and resilience, for both species richness and density of the total assemblage. Neither did roughness affect the resistance and resilience of the total algal assemblage or of the algal life forms separately, when evaluated using multivariate data sets (presence-absence and quantitative). Algal life forms differed in resistance and resilience; adnate/prostrate and erect/stalked species were more resistant and resilient than the other life forms (filamentous, motile and metaphytic). Additionally, motile species resisted and recovered better than did species that are only loosely associated with the substratum (metaphytic species). Substratum roughness had no pronounced effect on benthic algal resistance and resilience. The results of this and some other studies suggest that the intensity of disturbance determines the importance of habitat heterogeneity and flow refuges for benthic algae in streams. © 2012 Blackwell Publishing Ltd.

Giehl E.L.H.,Federal University of Sao Carlos | Jarenkow J.A.,Federal University of Rio Grande do Sul
Ecography | Year: 2012

Although detected long ago, latitudinal disparity in species richness lacks a consensus regarding its underlying mechanisms. We evaluated whether the main predictions derived from the tropical niche conservatism hypothesis help to explain differences regarding species richness and turnover of species and lineages between forests located in tropical and subtropical climates. If tropical niches are retained, we predict that only a subset of tropical lineages disperses and establishes outside the tropics; tip-level phylogenetic clustering increases outside the tropics; and the climatic variation drives species richness indirectly via constraints to the distribution of lineages. We compiled 58 checklists along tropical and subtropical sites of riparian forests in southeastern South America. We tested the frequency of niches shifts for species and lineages and the abundance of taxa in each climate. Next, we checked the likelihood of pathways linking climatic and spatial predictors directly with species richness and via phylogenetic clustering estimates. Several lineages only occurred in the tropics, and the number of species and lineages that occurred in both climates was lower than expected by chance. Conversely, few lineages were exclusively subtropical and diversified in the subtropics. Phylogenetic clustering increased in subtropical sites and was correlated with decreasing species richness. An interaction between mean temperature of coldest quarter and precipitation seasonality explained most variation in species richness via increases in phylogenetic clustering. These results support an important contribution of climatic niche conservatism to explain richness disparities between tropics and subtropics, mainly because of the inability of most lineages to colonize the subtropics, which is very likely related to cold intolerance. Since niche conservatism likely drives most of the variation in tree species richness in the region, it provides a mechanistic interpretation of the observed patterns, thus fostering the understanding of richness disparities between these tropical and subtropical tree communities. © 2012 The Authors.

Sellitto M.,United World College in Mostar | De Martino D.,International School for Advanced Studies | Caccioli F.,International School for Advanced Studies | Arenzon J.J.,Federal University of Rio Grande do Sul
Physical Review Letters | Year: 2010

We show that facilitated spin mixtures with a tunable facilitation reproduce, on a Bethe lattice, the simplest higher-order singularity scenario predicted by the mode-coupling theory (MCT) of liquid-glass transition. Depending on the facilitation strength, they yield either a discontinuous glass transition or a continuous one, with no underlying thermodynamic singularity. Similar results are obtained for facilitated spin models on a diluted Bethe lattice. The mechanism of dynamical arrest in these systems can be interpreted in terms of bootstrap and standard percolation and corresponds to a crossover from a compact to a fractal structure of the incipient spanning cluster of frozen spins. Theoretical and numerical simulation results are fully consistent with MCT predictions. © 2010 The American Physical Society.

Goncalves Ferrari G.,Leiden University | Goncalves Ferrari G.,Federal University of Rio Grande do Sul | Boekholt T.,Leiden University | Portegies Zwart S.F.,Leiden University
Monthly Notices of the Royal Astronomical Society | Year: 2014

We developed a Keplerian-based Hamiltonian splitting for solving the gravitational N-body problem. This splitting allows us to approximate the solution of a general N-body problem by a composition of multiple, independently evolved two-body problems. While the Hamiltonian splitting is exact, we show that the composition of independent two-body problems results in a non-symplectic non-time-symmetric first-order map. A time-symmetric second-order map is then constructed by composing this basic first-order map with its self-adjoint. The resulting method is precise for each individual two-body solution and produces quick and accurate results for near-Keplerian N-body systems, like planetary systems or a cluster of stars that orbit a supermassive black hole. The method is also suitable for integration of N-body systems with intrinsic hierarchies, like a star cluster with primordial binaries. The superposition of Kepler solutions for each pair of particles makes the method excellently suited for parallel computing; we achieve ≥64 per cent efficiency for only eight particles per core, but close to perfect scaling for 16 384 particles on a 128 core distributed-memory computer. We present several implementations in SAKURA, one of which is publicly available via the AMUSE framework. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Saada Z.,National Engineering School of Tunis | Maghous S.,Federal University of Rio Grande do Sul | Garnier D.,Laboratoire des Materiaux et Structures du Genie Civil
International Journal for Numerical and Analytical Methods in Geomechanics | Year: 2011

The seismic bearing capacity of shallow foundations resting on a modified Hoek-Brown rock mass is investigated within the framework of the kinematic approach of limit analysis theory. The analysis focuses on evaluating the reduction in bearing capacity induced by seismic loading and by the proximity of a rock slope. A pseudo-static approach is adopted to account for the earthquake effects for the seismic bearing capacity evaluations. At the rock material level, the closed-form expressions previously obtained for the support functions of the rock failure criterion allow the implementation of different failure mechanisms families, and thus to derive rigorous upper bounds estimates of the load-bearing capacity in both static and seismic conditions. The effects of geometrical, strength and loading parameters are assessed through a large number of parametric computations. Finally, design tables are presented for practical use in rock engineering. © 2010 John Wiley & Sons, Ltd.

Ritter A.C.,University of Bologna | Tondo E.C.,Federal University of Rio Grande do Sul
Journal of Infection in Developing Countries | Year: 2014

Foodborne diseases are typically caused by the ingestion of food contaminated with micro-organisms or their toxins, resulting in gastrointestinal disorders and in some severe cases hospitalization and death. In Brazil, foodborne illnesses are caused mainly by Salmonella, Staphylococcus aureus and Escherichia coli. The most important contributing factors for outbreaks are exposure of foods to unsuitable temperatures, inadequate food preparation and contamination of raw material or water used to prepare food. Recently, aiming to prevent foodborne illnesses during the 2014 FIFA World Cup, Brazil has developed a risk-based evaluation tool able to assess and grade Brazilian food services in cities that will host football matches. This tool has been used by the Brazilian sanitary surveillance officers during the inspection of facilities where food services. This is considered an innovative preventative sanitary action because it was created based on scientific information, statistical calculation and on risks of foodborne diseases occurrence. In this mini-review we summarize general data, control measures and how travellers can prevent foodborne illness in Brazil during the 2014 FIFA World Cup. © 2014 Ritter et al.

Senaha M.L.H.,University of Montesquieu | De Mattos Pimenta Parente M.A.,Federal University of Rio Grande do Sul
Behavioural Neurology | Year: 2012

The Japanese language is represented by two different codes: syllabic and logographic while Portuguese employs an alphabetic writing system. Studies on bilingual Portuguese-Japanese individuals with acquired dyslexia therefore allow an investigation of the interaction between reading strategies and characteristics of three different writing codes. The aim of this study was to examine the differential impact of an acquired brain lesion on the reading of the logographic, syllabic and alphabetic writing systems of a bilingual Portuguese-Japanese aphasic patient (PF). Results showed impaired reading in the logographic system and when reading irregularly spelled Portuguese words but no effects on reading regular words and nonwords in syllabic and alphabetic writing systems. These dissociations are interpreted according to a multi-route cognitive model of reading assuming selective damage in the lexical route can result in acquired dyslexia across at least three different writing codes. © 2012 - IOS Press and the authors. All rights reserved.

Erthal F.,Federal University of Rio Grande do Sul | Kotzian C.B.,Federal University of Santa Maria | Simoes M.G.,Sao Paulo State University
Palaios | Year: 2011

This study is the first assessment of mollusk fossil assemblages relative to the compositional fidelity of modern mollusk living and death assemblages. It also shows that the sedimentary record can provide information on the original, non-human-impacted, freshwater malacofauna biodiversity, based on Late Pleistocene shells. The fossil mollusk assemblage from the Touro Passo Formation (Pleistocene-Holocene) was compared to living and death assemblages of the Touro Passo River, southern Brazil, revealing little resemblance between fossil and live-dead species composition. Although the living and death assemblages agree closely in richness, species composition, and species relative abundances (both proportional and rank), the fossil assemblage differs significantly from both modern assemblages in most of these measures. The fossil assemblage is dominated by the native endemic corbiculid bivalve Cyanocyclas limosa and the gastropod Heleobia aff. bertoniana. These are absent in the living assemblages, and both living and death assemblages are dominated by the alien Asiatic corbiculid C. fluminea, which is absent in the fossil assemblage. The fossil assemblage also contains, overall, a higher proportional abundance of relatively thick-shelled species, suggesting a genuine bias against the thinner-and smaller-shelled species. Our results suggest that contemporary environmental changes, such as the introduction of some alien freshwater mollusk species, together with post-burial taphonomic processes, are the main factors leading to the poor fidelity of the fossil assemblage studied. Hence, the taxonomic composition of the Late Pleistocene mollusks from the Touro Passo Formation probably would show greater similarity to present-day assemblages wherever the mollusk biodiversity is not disturbed by human activities. © 2011 SEPM (Society for Sedimentary Geology).

Garcia-Galan C.,Institute Catalisis CSIC | Berenguer-Murcia A.,University of Alicante | Fernandez-Lafuente R.,Institute Catalisis CSIC | Rodrigues R.C.,Federal University of Rio Grande do Sul
Advanced Synthesis and Catalysis | Year: 2011

Enzyme biocatalysis plays a very relevant role in the development of many chemical industries, e.g., energy, food or fine chemistry. To achieve this goal, enzyme immobilization is a usual pre-requisite as a solution to get reusable biocatalysts and thus decrease the price of this relatively expensive compound. However, a proper immobilization technique may permit far more than to get a reusable enzyme; it may be used to improve enzyme performance by improving some enzyme limitations: enzyme purity, stability (including the possibility of enzyme reactivation), activity, specificity, selectivity, or inhibitions. Among the diverse immobilization techniques, the use of pre-existing supports to immobilize enzymes (via covalent or physical coupling) and the immobilization without supports [enzyme crosslinked aggregates (CLEAs) or crystals (CLECs)] are the most used or promising ones. This paper intends to give the advantages and disadvantages of the different existing immobilization strategies to solve the different aforementioned enzyme limitations. Moreover, the use of nanoparticles as immobilization supports is achieving an increasing importance, as the nanoparticles versatility increases and becomes more accessible to the researchers. We will also discuss here some of the advantages and drawbacks of these non porous supports compared to conventional porous supports. Although there are no universal optimal solutions for all cases, we will try to give some advice to select the optimal strategy for each particular enzyme and process, considering the enzyme properties, nature of the process and of the substrate. In some occasions the selection will be compulsory, for example due to the nature of the substrate. In other cases the optimal biocatalyst may depend on the company requirements (e.g., volumetric activity, enzyme stability, etc). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wong A.,University of Waterloo | Scharcanski J.,Federal University of Rio Grande do Sul
Digital Signal Processing: A Review Journal | Year: 2012

In this paper, a novel stochastic method is developed for despeckling transrectal ultrasound (TRUS) images of the prostate. By incorporating the circular probe acquisition particularities and speckle noise statistics of TRUS images of the prostate into a likelihood-weighted Monte Carlo estimation scheme, the proposed method can better remove speckle noise while preserving image structures and details that are relevant for image screening, allowing for a better delineation of the lesion contour. Our in silico and in vivo experimental results are promising, which was confirmed by a clinical evaluation of the in vivo test cases by experienced clinicians, and indicate that our method potentially can perform better than other previously proposed methods. © 2012 Elsevier Inc. All rights reserved.

Grings M.,Federal University of Rio Grande do Sul | Ribas O.S.,Museu Botanico Municipal de Curitiba Herbario MBM
Phytotaxa | Year: 2013

Mimosa sobralii (Fabaceae), a new species of tree endemic to the northern highland slopes of the Brazilian state of Rio Grande do Sul, is described and illustrated. The new species is close to M. bifurca, from which it is set apart by the arborescent habit, yellow flowers and differences in leaflet morphology. © 2013 Magnolia Press.

Rodrigues R.C.,Federal University of Rio Grande do Sul | Fernandez-Lafuente R.,Institute Catalisis CSIC
Journal of Molecular Catalysis B: Enzymatic | Year: 2010

The lipase from Rhizomucor miehei (formerly Mucor miehei) (RML) is a commercially available enzyme in both soluble and immobilized form with very high activity and good stability under diverse conditions (anhydrous organic solvents, supercritical fluids, etc.). Although this lipase was initially produced to be used in food industry, in this review we will focus our attention on the application of this enzyme in organic chemistry, from biodiesel production to fine chemicals (mainly in enantio or regioselective or specific processes). After showing the enzyme features, some of the most efficient methods of RML immobilization will be commented (entrapping on reverse micelles, preparation of cross-linked RML aggregates or immobilization on pre-existing solids). Finally, the main uses of the enzyme in organic chemistry will be revised. The use of RML in the production of biodiesel will be analyzed, and compared to the performance of other lipases. The synthesis of esters of carboxylic acids as flavors is other example where RML has been successfully employed. Taking advantage of the wide specificity of the enzyme, mainly a high enantiospecificity, many examples of the use of RML in the resolution of racemic mixtures of chiral carboxylic acids, alcohols or esters will be presented. Special mention requires the use of the regioselectivity of RML, mainly the chemistry of sugars. Finally, more unusual uses of RML will be presented (anomalous substrates, novel uses, etc.). In general, this enzyme seems very adequate for esterification reactions due to its high stability in anhydrous media and good esterification activity. © 2010 Elsevier B.V.

Rodrigues R.C.,Federal University of Rio Grande do Sul | Berenguer-Murcia A.,University of Alicante | Fernandez-Lafuente R.,Institute Catalisis CSIC
Advanced Synthesis and Catalysis | Year: 2011

Chemical modification and immobilization of enzymes have been usually considered unrelated tools to improve biocatalyst features. However, there are many examples where a chemically modified enzyme is finally used in an immobilized form, and that exemplifies how both tools may be complementary resulting in a synergism in the final results. In this review we present some of the strategies that may give that result. For example, the chemical modification of soluble enzymes may be used to improve their immobilization (reinforcing adsorption or improving multipoint covalent attachment), or just to improve enzyme stability and facilitate the selection of the immobilization conditions. Chemical modification of previously immobilized enzymes benefits from solid-phase chemistry due to the nature of enzymes (e.g., prevention of inactivation, aggregation, etc.). The use of different targets for chemical modifications with small molecules or multifunctional polymers are also discussed: intramolecular or intersubunit cross-linking, one-point modification, generation of artificial microenvironments, etc. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Iturrioz I.,Federal University of Rio Grande do Sul | Lacidogna G.,Polytechnic University of Turin | Carpinteri A.,Polytechnic University of Turin
Engineering Fracture Mechanics | Year: 2013

In this work, the Acoustic Emission signals were captured by sensors applied to the external surfaces of a prismatic concrete specimen subjected to compression loads. In this context, the experimental results are presented in terms of stress-time diagram and also, the variation in the Gutenberg-Richter law, that is, the relation proposed between the Acoustic Emission cumulative counts and its magnitude. This law is obtained during each phase of the test and in the final stage.A three-dimensional lattice model, known as truss-like Discrete Element Method, also modeled the same specimen. The numerical results present a good correlation with those obtained from the experimental test also in terms of typical Acoustic Emission parameters, such as count rate, cumulative counts, and the variation in the Gutenberg-Richter law.Using the truss-like discrete element model, the relationship between the Acoustic Emission signal magnitude and the energy released from each localized rupture has also been analyzed. The obtained results are compatible with the Gutenberg-Richter energy-magnitude relation. Finally, the numerical results have been analyzed in terms of Acoustic Emission signal frequency. The simulation presents the same pattern with the experimental results: a shift towards lower Acoustic Emission signal frequencies during the evolution of the damage process. © 2013 Elsevier Ltd.

Pillar V.D.,Federal University of Rio Grande do Sul
Community Ecology | Year: 2013

Multivariate analysis of variance, based on randomization (permutation) test, has become an important tool for ecological data analyses. However, a comprehensive evaluation of the accuracy and power of available methods is still lacking. This is a thorough examination of randomization tests for multivariate group mean differences. With simulated data, the accuracy and power of randomization tests were evaluated using different test statistics in one-factor multivariate analysis of variance (MANOVA). The evaluations span a wide spectrum of data types, including specified and unspecified (field data) distributional properties, correlation structures, homogeneous to very heterogeneous variances, and balanced an unbalanced group sizes. The choice of test statistic strongly affected the results. Sums of squares between groups (Qb) computed on Euclidean distances (Qb-EUD) gave better accuracy. Qb on Bray-Curtis, Manhattan or Chord distances, the multiresponse permutation procedure (MRPP) and the sum of univariate ANOVA F produced severely inflated type I errors under increasing variance heterogeneity among groups, a common scenario in ecological data. Despite pervasive claims in the ecological literature, the evidence thus suggests caution when using test statistics other than Qb-EUD.

Oliveira C.P.M.S.D.,University of Sao Paulo | Stefano J.T.,University of Sao Paulo | Alvares-Da-Silva M.R.,Federal University of Rio Grande do Sul
Expert Review of Gastroenterology and Hepatology | Year: 2013

Liver transplantation is the standard of care for acute and chronic end-stage liver disease. Advances in medical therapy and surgical techniques have transformed the long-term survival of liver-transplant (LT) recipients. The prevalence of post-transplant cardiovascular complications has been rising with increased life expectancy after liver transplantation. Currently, deaths related to cardiovascular complications are one of the main causes of long-term mortality in LT recipients, as cardiovascular disease is the reason of 19-42% of non-liver-related mortality after transplant. On the other hand, metabolic syndrome is common among LT recipients before and after transplantation. In fact, their components (abdominal obesity, diabetes mellitus, hypertension and dyslipidemia) are often exacerbated by transplant-specific factors, such as immunosuppression, inappropriate diet, smoking and a sedentary lifestyle, and add a significant risk of developing atherosclerosis. These aspects are discussed in this article. © 2013 Expert Reviews Ltd.

Adams B.D.,University of Waterloo | Radtke C.,University of Waterloo | Radtke C.,Federal University of Rio Grande do Sul | Black R.,University of Waterloo | And 3 more authors.
Energy and Environmental Science | Year: 2013

We report a significant difference in the growth mechanism of Li 2O2 in Li-O2 batteries for toroidal and thin-film morphologies which is dependent on the current rate that governs the electrochemical pathway. Evidence from diffraction, electrochemical, FESEM and STEM measurements shows that slower current densities favor aggregation of lithium peroxide nanocrystallites nucleated via solution dismutase on the surface of the electrode; whereas fast rates deposit quasi-amorphous thin films. The latter provide a lower overpotential on charge due to their nature and close contact with the conductive electrode surface, albeit at the expense of lower discharge capacity. © 2013 The Royal Society of Chemistry.

Vignolo L.D.,CONICET | Milone D.H.,CONICET | Scharcanski J.,Federal University of Rio Grande do Sul
Expert Systems with Applications | Year: 2013

Feature selection is a key issue in pattern recognition, specially when prior knowledge of the most discriminant features is not available. Moreover, in order to perform the classification task with reduced complexity and acceptable performance, usually features that are irrelevant, redundant, or noisy are excluded from the problem representation. This work presents a multi-objective wrapper, based on genetic algorithms, to select the most relevant set of features for face recognition tasks. The proposed strategy explores the space of multiple feasible selections in order to minimize the cardinality of the feature subset, and at the same time to maximize its discriminative capacity. Experimental results show that, in comparison with other state-of-the-art approaches, the proposed approach allows to improve the classification performance, while reducing the representation dimensionality. © 2013 Elsevier Ltd. All rights reserved.

Nemmen R.S.,Federal University of Rio Grande do Sul | Brotherton M.S.,University of Wyoming
Monthly Notices of the Royal Astronomical Society | Year: 2010

Bolometric corrections based on the optical-to-ultraviolet continuum spectrum of quasars are widely used to quantify their radiative output, although such estimates are affected by a myriad of uncertainties, such as the generally unknown line-of-sight angle to the central engine. In order to shed light on these issues, we investigate the state-of-the-art models of Hubeny et al. that describe the continuum spectrum of thin accretion discs and include relativistic effects. We explore the bolometric corrections as a function of mass accretion rates, black hole masses and viewing angles, restricted to the parameter space expected for type 1 quasars. We find that a non-linear relationship log Lbol=A+B log(λLλ) with B≤ 0.9 is favoured by the models and becomes tighter as the wavelength decreases. We calculate from the model the bolometric corrections corresponding to the wavelengths λ= 1450, 3000 and 5100 Å. In particular, for λ= 3000 Å we find A= 9.24 ± 0.77 and B= 0.81 ± 0.02. We demonstrate that the often made assumption that quasars emit isotropically may lead to severe systematic errors in the determination of Lbol, when using the method of integrating the 'big blue bump' spectrum. For a typical viewing angle of ≈30° to the quasar central engine, we obtain that the value of Lbol resulting from the isotropy assumption has a systematic error of ≈30 per cent high compared to the value of Lbol which incorporates the anisotropic emission of the accretion disc. These results are of direct relevance to observational determinations of the bolometric luminosities of quasars, and may be used to improve such estimates. © 2010 The Authors. Journal compilation © 2010 RAS.

Lorenzini G.,University of Parma | Biserni C.,University of Bologna | Rocha L.A.O.,Federal University of Rio Grande do Sul
International Journal of Heat and Mass Transfer | Year: 2011

In this paper we consider the optimization of shape of an isothermal cavity that intrudes into a solid conducting wall. The main objective is the minimization of the global thermal resistance between the solid wall and the cavity, which removes heat from the wall. Two sets of geometries have been considered: T and Y-shaped cavities. The double optimization with reference to the two degrees of freedom D0/D1 and L0/L 1 has demonstrated that the global thermal resistance decreases as the volume fraction occupied by the rectangle defined by the 'stem' intrusion increases. The geometrical optimization of Y-shaped cavity has been performed by varying the angle between the tributary branch and the horizontal axis, as well as, by varying the ratio between the volume of the fin and the rectangular volume that circumscribes it (ψ), while the other geometric parameters are maintained fixed. For the same values of ψ, it was observed that there was one specific angle α that optimized the heat removal from the conducting solid wall to the cavity. It was also highlighted that the optimal angle is the one that distributes more uniformly the hot spots along the conducting solid wall, in accordance to the Constructal principle of "optimal distribution of imperfections". Finally, the performance of the Y-shaped cavity proved to be approximately 35% superior to that of the C-shaped cavity under the same geometric and thermal conditions. © 2011 Elsevier Ltd. All rights reserved.

Bailey C.J.,Aston University | Gross J.L.,Federal University of Rio Grande do Sul | Hennicken D.,Bristol Myers Squibb | Iqbal N.,Bristol Myers Squibb | And 2 more authors.
BMC Medicine | Year: 2013

Background: Management of type 2 diabetes with metformin often does not provide adequate glycemic control, thereby necessitating add-on treatment. In a 24-week clinical trial, dapagliflozin, an investigational sodium glucose cotransporter 2 inhibitor, improved glycemic control in patients inadequately controlled with metformin. The present study is an extension that was undertaken to evaluate dapagliflozin as long-term therapy in this population.Methods: This was a long-term extension (total 102 weeks) of a 24-week phase 3, multicenter, randomized, placebo-controlled, double-blind, parallel-group trial. Patients were randomly assigned (1:1:1:1) to blinded daily treatment (placebo, or dapagliflozin 2.5 to 5, or 10 mg) plus open-label metformin (≥1,500 mg). The previously published primary endpoint was change from baseline in glycated hemoglobin (HbA1c) at 24 weeks. This paper reports the follow-up to week 102, with analysis of covariance model performed at 24 weeks with last observation carried forward; a repeated measures analysis was utilized to evaluate changes from baseline in HbA1c, fasting plasma glucose (FPG), and weight.Results: A total of 546 patients were randomized to 1 of the 4 treatments. The completion rate for the 78-week double-blind extension period was lower for the placebo group (63.5%) than for the dapagliflozin groups (68.3% to 79.8%). At week 102, mean changes from baseline HbA1c (8.06%) were +0.02% for placebo compared with -0.48% (P = 0.0008), -0.58% (P <0.0001), and -0.78% (P <0.0001) for dapagliflozin 2.5 to 5, and 10 mg, respectively. In addition, all dapagliflozin groups had sustained reductions from baseline in FPG (-1.07 to -1.47 mmol/l) and body weight (-1.10 to -1.74 kg) at 102 weeks, whereas increases were noted in placebo-treated patients for both of these outcomes. Events of hypoglycemia were rare and were not severe. Evidence suggestive of genital infection was reported in 11.7% to 14.6% of dapagliflozin patients and 5.1% of placebo patients, with one related discontinuation (dapagliflozin 5 mg). Evidence suggestive of urinary tract infection was reported in 8.0% to 13.3% of dapagliflozin patients and 8.0% of placebo patients, with one related discontinuation (dapagliflozin 2.5 mg).Conclusions: Dapagliflozin added to metformin for 102 weeks enabled sustained reductions in HbA1c, FPG, and weight without increased risk of hypoglycemia in patients with type 2 diabetes who were inadequately controlled on metformin alone.Trial registration: ClinicalTrials.gov: NCT00528879. © 2013 Bailey et al; licensee BioMed Central Ltd.

Patel V.,London School of Hygiene and Tropical Medicine | Kieling C.,Federal University of Rio Grande do Sul | Maulik P.K.,George Institute for Global Health | Maulik P.K.,University of Oxford | Divan G.,Sangath
Archives of Disease in Childhood | Year: 2013

Developmental disabilities, emotional disorders and disruptive behaviour disorders are the leading mental health-related causes of the global burden of disease in children aged below 10 years. This article aims to address the treatment gap for child mental disorders through synthesising three bodies of evidence: the global evidence base on the treatment of these priority disorders; the barriers to implementation of this knowledge; and the innovative approaches taken to address these barriers and improve access to care. Our focus is on low-resource settings, which are mostly found in low- and middle-income countries (LMIC). Despite the evidence base on the burden of child mental disorders and their long-term consequences, and the recent mental health Gap Action Programme guidelines which testify to the effectiveness of a range of pharmacological and psychosocial interventions for these disorders, the vast majority of children in LMIC do not have access to these interventions. We identify three major barriers for the implementation of efficacious treatments: the lack of evidence on delivery of the treatments, the low levels of detection of child mental disorders and the shortage of skilled child mental health professionals. The evidence based on implementation, although weak, supports the use of screening measures for detection of probable disorders, coupled with a second-stage diagnostic assessment and the use of nonspecialist workers in community and school settings for the delivery of psychosocial interventions. The most viable strategy to address the treatment gap is through the empowerment of existing human resources who are most intimately concerned with child care, including parents, through innovative technologies, such as mobile health, with the necessary skills for the detection and treatment of child mental disorders.

Schernthaner G.,Rudolfstiftung Hospital Vienna | Gross J.L.,Federal University of Rio Grande do Sul | Rosenstock J.,Dallas Diabetes and Endocrine Center at Medical City | Guarisco M.,Stanocola Medical Clinic | And 5 more authors.
Diabetes Care | Year: 2013

OBJECTIVE-To evaluate the efficacy and safety of canagliflozin, a sodium glucose cotransporter 2 inhibitor, compared with sitagliptin in subjects with type 2 diabetes inadequately controlled with metformin plus sulfonylurea. RESEARCH DESIGN AND METHODS-In this 52-week, randomized, double-blind, active-controlled, phase 3 study, subjects using stable metformin plus sulfonylurea (N = 755) received canagliflozin 300 mg or sitagliptin 100 mg daily. Primary end point was change from baseline in A1C at 52 weeks. Secondary end points included change in fasting plasma glucose (FPG) and systolic blood pressure (BP), and percent change in body weight, triglycerides, and HDL cholesterol. Safety was assessed based on adverse event (AE) reports. RESULTS-At 52 weeks, canagliflozin 300mg demonstrated noninferiority and, in a subsequent assessment, showed superiority to sitagliptin 100 mgin reducing A1C(-1.03%[-11.3mmol/mol] and -0.66% [-7.2 mmol/mol], respectively; least squares mean difference between groups, -0.37% [95% CI, -0.50 to -0.25] or -4.0 mmol/mol [-5.5 to -2.7]). Greater reductions in FPG, body weight, and systolic BP were observed with canagliflozin versus sitagliptin (P < 0.001). Overall AE rates were similar with canagliflozin (76.7%) and sitagliptin (77.5%); incidence of serious AEs and AE-related discontinuations was low for both groups. Higher incidences of genital mycotic infections and osmotic diuresis-related AEs were observed with canagliflozin, which led to one discontinuation. Hypoglycemia rates were similar in both groups. CONCLUSIONS-Findings suggest that canagliflozinmay be a new therapeutic tool providing better improvement in glycemic control and body weight reduction than sitagliptin, but with increased genital infections in subjects with type 2 diabetes using metformin plus sulfonylurea. © 2013 by the American Diabetes Association.

Dupont J.,Federal University of Rio Grande do Sul
Accounts of Chemical Research | Year: 2011

Ionic liquids (ILs), a special group of classical molten salts, are widely used in various fields of science. Historically, researchers have tested ILs out of curiosity or to improve a specific property in a particular system in many areas of chemistry or materials science. However, today, ILs are far from being simple chemical curiosities and sit at the center of various green industrial innovation processes, where they play important roles in materials extraction, reactive catalytic supports, spatial devices, and biotransformations.In this Account, we describe a journey into a nanostructured universe to better understand the unique properties of ionic liquids and their modern applications. Because molten salts have been known for centuries and have found limited uses, we try to explain why modern nonaqueous ILs deserve increased interest and curiosity. We discuss the characteristics that distinguish modern nonaqueous ILs and compare them with classical molten salts.One of the main differences between room temperature ILs, especially those based on imidazolium cations, and simple molten salts, is the molecular asymmetry built into at least one of the ions. This asymmetry in modern, nonaqueous ILs opposes the strong charge ordering due to ionic interactions that normally would cause the system to crystallize. In addition, the presence of a cooperative network of hydrogen bonds between the cations and anions induces structural directionality (the entropic effect). Therefore, modern ILs form preorganized structures, mainly through hydrogen bonding, that induce structural directionality. In contrast, classical salts form aggregates only through ionic bonds. In other words, weak interactions order the structures in modern ILs while charges order the structure within classical salts.ILs cannot be regarded as merely homogeneous solvents. In fact, ILs form extended hydrogen-bond networks with polar and nonpolar nano domains and therefore are by definition "supramolecular" fluids. Thus, ILs are better described as hydrogen-bonded polymeric supramolecules of the type [(DAI)m(X)m-n)] n+[(DAI)m-n(X)x)]n-. This structural pattern is a general trend for both the solid and the liquid phase and is apparently maintained to a large extent even in the gas phase. This structural organization of ILs can be used as entropic drivers (the "IL effect") for the preparation of well-defined nanoscale structures with extended order, either in the bulk phase or at the gas/vacuum interface. © 2011 American Chemical Society.

Lewis K.T.,Dickinson College | Eracleous M.,Pennsylvania State University | Storchi-Bergmann T.,Federal University of Rio Grande do Sul
Astrophysical Journal, Supplement Series | Year: 2010

An increasing number of active galactic nuclei (AGNs) exhibit broad, double-peaked Balmer emission lines, which represent some of the best evidence for the existence of relatively large-scale accretion disks in AGNs. A set of 20 double-peaked emitters have been monitored for nearly a decade in order to observe long-term variations in the profiles of the double-peaked Balmer lines. Variations generally occur on timescales of years, and are attributed to physical changes in the accretion disk. Here we characterize the variability of a subset of seven double-peaked emitters in a model independent way. We find that variability is caused primarily by the presence of one or more discrete "lumps" of excess emission; over a timescale of a year (and sometimes less) these lumps change in amplitude and shape, but the projected velocity of these lumps changes over much longer timescales (several years). We also find that all of the objects exhibit red peaks that are stronger than the blue peak at some epochs and/or blueshifts in the overall profile, contrary to the expectations for a simple, circular accretion disk model, thus emphasizing the need for asymmetries in the accretion disk. Comparisons with two simple models, an elliptical accretion disk and a circular disk with a spiral arm, are unable to reproduce all aspects of the observed variability, although both account for some of the observed behaviors. Three of the seven objects have robust estimates of the black hole masses. For these objects the observed variability timescale is consistent with the expected precession timescale for a spiral arm, but incompatible with that of an elliptical accretion disk. We suggest that with the simple modification of allowing the spiral arm to be fragmented, many of the observed variability patterns could be reproduced. © 2010. The American Astronomical Society. All rights reserved.

Milesi S.V.,Federal University of Rio Grande do Sul | Melo A.S.,Federal University of Goais
Canadian Journal of Fisheries and Aquatic Sciences | Year: 2014

Tributaries may affect fauna in a mainstream by changing bottom substrate and increasing spatial heterogeneity. Additionally, we hypothesized that fauna in the mainstream may be affected by drifting migrants from tributaries. In nine stream networks, we sampled a similar microhabitat immediately upstream and downstream of two confluences. In each network, one confluence was located in the network centre and one in the periphery, and they were distinguished by low and high ratios of tributary size, respectively.Weassessed whether the aquatic fauna at sites downstream from confluences was species-richer, distinct in composition and structure, and whether it included the fauna of upstream sites. We found that richness, rarefied richness, and abundance at downstream sites were not higher than at their upstream counterparts. Faunas at downstream sites were not nested subsets of those at upstream sites. Macroinvertebrate assemblage composition and structure differed between downstream and upstream sites in the peripheral confluences (high tributary to mainstream (T:M) ratios), but not in central confluences (low T:M ratios). Thus, effects of small tributaries on receiving mainstreams are dependent on the T:M ratio.

Dahmen S.R.,Federal University of Rio Grande do Sul
European Physical Journal H | Year: 2015

In this article Denis Diderot’s Fifth Memoir of 1748 on the problem of a pendulum damped by air resistance is discussed in its historical as well as mathematical aspects. Diderot wrote the Memoir in order to clarify an assumption Newton made without further justification in the first pages of the Principia in connection with an experiment to verify the Third Law of Motion using colliding pendulums. To explain the differences between experimental and theoretical values, Newton assumed the bob was traversed. By giving Newton’s arguments a mathematical scaffolding and recasting his geometrical reasoning in the language of differential calculus, Diderot provided a step-by-step solution guide to the problem. He also showed that Newton’s assumption was equivalent to having assumed FR proportional the bob’s velocity v, when in fact he believed it should be replaced by FR ∼ v2. His solution is presented in full detail and his results are compared to those obtained from a Lindstedt-Poincaré approximation for an oscillator with quadratic damping. It is shown that, up to a prefactor, both results coincide. Some results that follow from his approach are presented and discussed for the first time. Experimental evidence to support Diderot’s or Newton’s claims is discussed together with the limitations of their solutions. Some misprints in the original memoir are pointed out. © 2015, EDP Sciences and Springer-Verlag Berlin Heidelberg.

Vos M.,Australian National University | Grande P.L.,Federal University of Rio Grande do Sul
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2015

Electron scattering experiments at keV energies from a TiO2 surface are presented. The paper aims to give an overview of the wide variety of information that can be extracted from such experiments. If the elastic scattering cross sections are known these experiments give the sample composition, if the composition is known one can extract the ratio of the elastic cross sections. In the experiments described here the ratio of the Ti and O cross sections deviates noticeably from the one calculated from the Rutherford formula. The peak widths give access to the mean kinetic energies of the atoms present. We show that the mean kinetic energy of Ti atoms is less than that of O atoms, but both kinetic energies are still affected by quantum effects, i.e. are larger than 3/2kT. We extract an estimate of the dielectric function of TiO2 by extending the measurement up to 100 eV energy loss. At these high energies the determination of the dielectric function from the measured energy loss spectrum is relatively simple, as the contribution of surface excitations is small and the obtained loss function is closely related to the dielectric function in the optical limit. Finally, we use the technique to monitor the surface after sputtering with Ar+ ions, and observe both differences in composition and electronic structure induced by sputtering that disappear again after annealing. © 2014 Elsevier B.V.

Fragoso S.,Federal University of Rio Grande do Sul
New Review of Hypermedia and Multimedia | Year: 2011

Web Science has favoured macroscopic approaches which have revealed much about the Web's structural patterns. We argue that contextualised knowledge about hyperlinks on the Web has not advanced at the same rate and that complementary intermediate and micro-scale investigations are essential for a better understanding of the motivations, functions and meanings of these links. We present an investigation that attempted to overcome the shortcomings of current theoretical frameworks and methodological techniques. The focus of this article lies in the demonstration of the viability of studying the web at different scales of analysis without loss of coherence guided by the assumption of the Web as media. Results of our quali-quantitative, multi-scale and study of the international connectivity of websites registered in Brazil are presented. At the macro-scale, previous indications of high international connectivity are confirmed. Intermediate (meso) and micro-scale analyses focused on the connectivity between Brazilian and German websites and contradicted the conclusions about the meanings and functions of hyperlinks commonly associated with structural analysis. Links between Brazilian and German websites were shown to derive from a large number of formal and generic links, challenging the prevalent association that large quantities of incoming links are an indication of high relevance. © 2011 Taylor & Francis.

Gomes H.M.,Federal University of Rio Grande do Sul
Expert Systems with Applications | Year: 2011

In this paper, a structural truss mass optimization on size and shape is performed taking into account frequency constraints. It is well-known that structural optimizations on shape and size are highly non-linear dynamic optimization problems since this mass reduction conflicts with the frequency constraints especially when they are lower bounded. Besides, vibration modes may switch easily due to shape modifications. This paper intends to investigate the use of a particle swarm optimization (PSO) algorithm as an optimization engine in this type of problem. This choice is based on reported well-behavior of such algorithm as global optimizer in other areas of knowledge. Another feature of the algorithm is taken into account for this choice, like the fact that it is not gradient based, but just based on simple objective function evaluation. The algorithm is briefly revised highlighting its most important features. It is presented four examples regarding the optimization of trusses on shape and size with frequency constraints. The examples are widely reported and used in the related literature as benchmarks. The results show that the algorithm performed similar to other methods and even better in some cases. © 2010 Elsevier Ltd. All rights reserved.

Meneghel S.N.,Federal University of Rio Grande do Sul | Hirakata V.N.,Grupo de Pesquisa e Pos Graduacao
Revista de Saude Publica | Year: 2011

Objective: To assess female homicide rates due to aggression according to sociodemographic and health indicators. Methods: Ecological study on female homicides due to aggression in Brazil between 2003 and 2007. Information on 19,459 deaths were obtained form the Brazilian Mortality Database. Standardized female homicide rates due to aggression were correlated with 28 socioeconomic, demographic and health indicators, using Pearson's correlation test. Multiple linear regression was performed including variables with p < 0.20 and excluding those with multicollinearity. Results: The standardized female homicide rate due to aggression was 4.1/100,000 during the study period. After adjustment, three variables remained significantly associated with female homicides: birth rate (p = 0.072), percentage of Evangelicals (p = 0.019) and male homicides due to aggression (p < 0.001). The model had a predictive power of 69% (r2 = 0.699). The Brazilian states of Espírito Santo, Pernambuco, Mato Grosso, Rio de Janeiro, Rondônia, Alagoas, Mato Grosso do Sul, Roraima e Amapá showed the highest rates during the study period. Conclusions: The female homicide rates due to aggression were high in Brazil and varied by region. The association with male homicides due to aggression stresses the importance of reducing structural violence to protect women against violence.

Goldani L.Z.,Federal University of Rio Grande do Sul
Journal of Clinical Gastroenterology | Year: 2011

Paracoccidioidomycosis is the most prevalent mycosis in Latin America. Although the lungs are the primary site of infection, physicians often see patients because of disseminated disease. Imported paracoccidioidomycosis has been described in different regions of the world in patients who lived in endemic areas. Gastrointestinal disease owing to P. brasiliensis is rarely recognized in life because of nonspecific clinical manifestations. Gastrointestinal disease can present as part of progressive dissemination of infection or as a result of local complications from a silent healing process. This review will summarize the salient features of gastrointestinal paracoccidioidomycosis. Copyright © 2011 by Lippincott Williams & Wilkins.

Yarmolinsky J.,London School of Hygiene and Tropical Medicine | Yarmolinsky J.,Federal University of Rio Grande do Sul | Gon G.,London School of Hygiene and Tropical Medicine | Edwards P.,London School of Hygiene and Tropical Medicine
Nutrition Reviews | Year: 2015

Context: Tea has been proposed as an antihypertensive agent for individuals with elevated blood pressure, yet the evidence for this has not been systematically reviewed to date. Objective: The aim of this review was to evaluate the effects of tea on blood pressure in individuals within the prehypertensive and hypertensive blood pressure ranges. Data Sources: The CENTRAL, PubMed, Embase, and Web of Science databases were searched for all relevant studies published from 1946 to September 27, 2013. Study Selection: The selection criteria included randomized controlled trials of adults whose blood pressure was within hypertensive or prehypertensive ranges and in which the applied intervention was green or black tea; controls consisting of placebo, minimal tea intervention, or no intervention; and a follow-up period of at least 2 months. Data Extraction: Two reviewers independently extracted data on participants, interventions, comparators, outcomes, and study design. Mean differences (MDs) and 95% confidence intervals (95%CIs) were pooled to generate summary effect estimates. Results: Meta-analyses of 10 trials (834 participants) showed statistically significant reductions in systolic blood pressure (MD -2.36mmHg, 95%CI -4.20 to -0.52) and diastolic blood pressure (MD -1.77mmHg, 95%CI -3.03 to -0.52) with tea consumption. Conclusions: Consumption of green or black tea can reduce blood pressure in individuals within prehypertensive and hypertensive ranges, although further investigation with studies of longer duration and stronger methodological quality is warranted to confirm these findings. © The Author(s) 2015.

Lenz G.,Federal University of Rio Grande do Sul
Frontiers in Bioscience - Scholar | Year: 2012

Cells capable of starting the track towards cancer are probably abundant in an organism, but the likelihood of any of these cells to evolve to a deadly disease is very low. This occurs in part due to several safekeeping mechanisms shaped by evolution to detect and eliminate potential cancer-forming cells, which will be defined here as endogenous anticancer mechanisms (EACMs). Virtually any cellular process has safekeeping mechanisms that detect and correct mishaps that could evolve into potentially harmful cellular behavior, but some aspects of these mechanisms seem to have been selected by evolution to protect organisms against cancer. The mechanisms that will be discussed here and in the reviews of this series are: cell senescence, DNA repair, cell cycle control, apoptosis, autophagy, block of the invasion and metastasis cascade, block of cell reprogramming and immune surveillance. Here I will present the basic features and the importance of each EACM and review the involvement of these processes in preventing cancer growth together with their importance in cancer prevention and therapeutics.

Lages W.F.,Federal University of Rio Grande do Sul
Studies in Computational Intelligence | Year: 2016

This tutorial chapter explains the implementation of controllers in the Robot Operating System. The inner working of the ROS real-time loop is explained with discussion of the classes used to implement it. Contrariwise to most available examples of implementation of controllers in ROS, which show the use of single input, single output controllers using the proportional-integral-derivative control law, here controllers are approached in a more general sense, so that any control law can be used. A complete example of implementation of a MIMO nonlinear controller is presented using the computed torque control law. The real-time aspects of the problem are also considered and the controller is ready for running in hard-real-time with the PREEMPT_RT kernel patch. The source code of examples are available at public repositories to enable readers to experiment with the examples and adapt them to their robots. © Springer International Publishing Switzerland 2016.

Martinez D.,Federal University of Rio Grande do Sul | Lenz M.C.S.,CEP and Sleep Clinic
Indian Journal of Medical Research | Year: 2010

Circadian rhythm sleep disorders are common conditions manifested as misalignment between the sleep period and the physical/social 24-h environmental cycle. Delayed sleep phase (typical in adolescents) and advanced sleep phase (frequent in the elderly), situations in which the sleep period is displaced to a later or earlier time, respectively, are the two most prevalent circadian rhythm sleep disorders. There are, however, nine possible diagnoses of clinical interest. Since light is the main cue used in synchronizing the biological clock, blind individuals and night-shift/rotating-shift workers are more prone to develop circadian rhythm sleep disorders. In this article, the circadian rhythm syndromes included in the new International Classification of Sleep Disorders are reviewed as well as the most recent guidelines for diagnosis and treatment.

Raineki C.,University of British Columbia | Lucion A.B.,Federal University of Rio Grande do Sul | Weinberg J.,University of British Columbia
Developmental Psychobiology | Year: 2014

As one of the first rodent models designed to investigate the effects of early-life experiences, the neonatal handling paradigm has helped us better understand how subtle changes in the infant environment can powerfully drive neurodevelopment of the immature brain in typical or atypical trajectories. Here, we review data from more than 50 years demonstrating the compelling effects of neonatal handling on behavior, physiology, and neural function across the lifespan. Moreover, we present data that challenge the classical view of neonatal handling as an animal model that results only in positive/beneficial outcomes. Indeed, the overall goal of this review is to offer the suggestion that the effects of early-life experiences-including neonatal handling-are nuanced rather than unidirectional. Both beneficial and negative outcomes may occur, depending on the parameters of testing, sex of the subject, and neurobehavioral system analyzed. © 2014 Wiley Periodicals, Inc.

Reboh S.,CNRS Toulouse Center for Materials Elaboration and Structural Studies | Barbot J.F.,University of Poitiers | Beaufort M.F.,University of Poitiers | Fichtner P.F.P.,Federal University of Rio Grande do Sul
Applied Physics Letters | Year: 2010

H and He ion implantations allow the formation of nanocracks within controlled subsurface depths in semiconducting materials. Upon annealing, crack propagation and coalescence provides a way of cutting monocrystalline thin films. Here, the mechanisms of coalescence by crack-tip interactions are depicted in (001) Si wafers. Starting from overpressurized He-cracks, subcritical propagation was activated by diffusional H. Nanocrack interaction can occur by elastic forces, causing tip folding, or by plastic deformation forming extended defects. These observations are discussed and modeled using elasticity and fracture mechanics. The model suggests that kinetic effects in the cutting process depend on the crack interplanar separations. © 2010 American Institute of Physics.

Frizzo M.E.,Federal University of Rio Grande do Sul
Medical Hypotheses | Year: 2013

Glycogen synthase kinase 3-β (GSK3β) has a pivotal role in several intracellular signaling cascades that are involved in gene transcription, cytoskeletal reorganization, energy metabolism, cell cycle regulation, and apoptosis. This kinase has pleiotropic functions, and the importance of its activity has recently been shown in neurons and platelets. In addition to its regulatory function in several physiological events, changes in GSK3β activity have been associated with many psychiatric and neurodegenerative illnesses, such as Alzheimer's disease, schizophrenia and autism-spectrum disorders. Beside the reports of its involvement in several pathologies, it has become increasingly apparent that GSK3β might be a common therapeutic target for different classes of psychiatric drugs, and also that the GSK3β ratio may be a useful parameter to determine the biochemical changes that might occur during antidepressant treatment. Although GSK3β is commonly described as a key enzyme in a plethora of signaling cascades, originally it was identified as playing an important role in the regulation of glycogen synthesis, given its ability to inactivate glycogen synthase (GS) by phosphorylation. Acting as a constitutively active kinase, GSK3β phosphorylates GS, which results in a decrease of glycogen production. GSK3β phosphorylation increases glycogen synthesis and storage, while its dephosphorylation decreases glycogen synthesis. Inactivation of GSK3β leads to dephosphorylation of GS and increase in glycogen synthesis in the adipose tissue, muscle and liver. Glycogen levels are reduced by antidepressant treatment, and this effect seems to be related to an effect of drugs on GSK3β activity. Peripherally, glycogen is also abundantly found in platelets, where it is considered a major energy source, required for a variety of its functions, including the release reaction. Recently, analysis of platelets from patients with late-life major depression showed that active forms of GSK3β expression were upregulated by continuous treatment with sertraline. Here, we hypothesized that the quantification of glycogen in platelets might be used as a peripheral biomarker of GSK3β activity. Since it has been recently demonstrated that the modulation of GSK3β activity causes changes in glycogen stores, the glycogen levels in platelets could be used to assay the effects of drugs that have this kinase as a target, or diseases where its activity is affected. In conclusion, we hypothesized that the determination of glycogen peripherally may be useful to indicate a change in the activity of this enzyme, providing a faster and non-invasive approach to guide the therapeutic procedures for the patient. © 2013 Elsevier Ltd.

Kment P.,National Museum | Garbelotto T.D.A.,Federal University of Rio Grande do Sul
Entomologica Americana | Year: 2016

Discimita linnavuorii, new genus and species (Hemiptera: Heteroptera: Pentatomidae: Pentatominae), is described from the Central African Republic. The genus is superficially similar to representatives of the Neotropical subfamily Discocephalinae, but the labium, which arises anteriad of the imaginary line traversing head at anterior limit of the eyes, exludes such a possibility. The new genus exhibits an unusual mixture of morphological characters that are present in Sciocorini, Triplatygini and Myrocheini, and it is tentatively placed in the tribe Myrocheini. © New York Entomological Society.

Weibel D.E.,Federal University of Rio Grande do Sul
Composite Interfaces | Year: 2010

Polyurethane (PU) and polystyrene (PS) films were functionalized by ultraviolet (UV) or selective synchrotron radiations (SR) in the presence of reactive gases. The UV-PU results were compared with lowpressure plasma treatments of the same films. Oxygen or acrylic acid vapours (AA) were used as reactive gases. X-ray photoelectron spectroscopy measurements of UV modified films in the presence of oxygen or AA matched the RF-plasma treatments results. It is shown that COO and C=O functional groups were incorporated at the polymer surface efficiently with both methodologies. In addition, near-edge X-ray absorption fine structure showed that a thin film of poly(acrylic acid) is formed over the PU and PS films during the UV irradiation in the presence of AA vapours. These results resemble previous AA low-power plasma treatments. PU and PS films were also selectively functionalized by SR using oxygen as reactive gas. Surface concentrations of COO and C=O functional groups were enhanced by C1s → σ*C-C excitation after irradiation and oxygen introduction. This efficient surface functionalization was clearly observed in PS films which do not have CO and COO groups in their molecular structure. Excitations involving transitions to π* orbital (π*C=C, π*C=O) led to much lower functionalization efficiency. The SR results can be explained by taking into account previous photon stimulated ion desorption studies of polymers. SR results may open new ways to functionalize polymer surfaces selectively and efficiently. © 2010 Koninklijke Brill NV, Leiden.

Rosa D.S.,Federal University of Rio Grande do Sul
RSC Advances | Year: 2012

NCP pincer palladacycle 1 has been reported as an excellent catalyst precursor for the Suzuki-Miyaura reaction. Now, it's properties have been evaluated in the Heck reaction. 1 is highly active for the coupling of ArI, ArBr and electron-poor ArCl with n-butyl acrylate showing limitations in the reaction of deactivated ArCl and sterically hindered olefins. © 2012 The Royal Society of Chemistry.

Babujian H.M.,Yerevan Physics Institute | Foerster A.,Federal University of Rio Grande do Sul | Karowski M.,Institute For Theoretische Physik
Journal of High Energy Physics | Year: 2013

A general form factor formula for the O(N) σ-model is constructed and applied to several operators. The large N limits of these form factors are computed and compared with the 1/N expansion of the O(N) σ-model in terms of Feynman graphs and full agreement is found. In particular, O(3) and O(4) form factors are discussed. For the O(3) σ-model several low particle form factors are calculated explicitly. © SISSA 2013.

Stanculescu I.,Nova Southeastern University | Manica C.C.,Federal University of Rio Grande do Sul
Computers and Mathematics with Applications | Year: 2010

This report develops and studies a new family of Navier-Stokes equation regularizations: Leray-Tikhonov regularizations with time relaxation models. This new family of turbulence models is based on a modification (consistent with the large scales) of Tikhonov-Lavrentiev regularization. With this approach, we obtain an approximation of the unfiltered solution by one filtering step. We introduce the modified Tikhonov deconvolution operator and study its mathematical properties. We also perform rigorous numerical analysis of a computationally attractive algorithm for this family of models and present numerical experiments using it. © 2010 Elsevier Ltd. All rights reserved.

Sonuga-Barke, Cortese, Fairchild, and Stringaris offer us new insights not only on the neuropsychological processes and neurobiological mechanisms involved in the decision-making process but also how some of the most relevant child mental disorders might impact this process through a very comprehensive review of the pertinent literature. Although it is difficult to select specific points for discussing in a so dense review, I would like to highlight some aspects for 'whetting readers appetite' and seduce them to be in contact with the fascinating neurobiology behind an essential aspect of our lives. Read the full article at doi: 10.1111/jcpp.12496 © 2016 Association for Child and Adolescent Mental Health.

Ottoni G.L.,Federal University of Health Sciences, Porto Alegre | Antoniolli E.,Federal University of Rio Grande do Sul | Lara D.R.,Grande Rio University
Chronobiology International | Year: 2012

Chronotype has long been associated with mental disorders and temperamental features. This study aims to investigate the association of circadian preference with a new model for emotional and affective temperament. In this Web survey, 6436 subjects (27.2 males) answered the Affective and Emotional Composite Temperament Scale (AFECTS), the Circadian Energy Scale (CIRENS), and questions on subjective sleep parameters for a sleep-based chronotype measure. Temperament was more strongly correlated with daily energy score than with chronotype. For emotional dimensions, Volition, Coping, and Control positively correlated with high and stable daily energy, contrary to Sensitivity. Evening types showed a less adaptive emotional profile than morning and intermediate types, who showed a relatively similar emotional pattern. Focus and order (facets of Control), energy (facet of Volition), caution (facet of Inhibition), and problem facing (facet of Coping) were distinctive for the three circadian types, being particularly low in evening types and high in morning types. Differences between affective temperaments were more pronounced for morning and afternoon than for evening scores. Cyclothymic and euphoric temperaments, which relate to bipolar disorders, and apathetic, volatile, and disinhibited temperaments, which relate to attention-deficithyperactivity disorder (ADHD), showed the latest chronotype (i.e., evening preference). In conclusion, temperament was more associated with absolute energy levels than with chronotype. Evening types had less emotional control, coping, volition, and caution, and more affective instability and externalization. The circadian daily energy profile can be very informative about human temperament and vice versa, and their combined assessment may be useful in the evaluation of psychiatric patients. © 2012 Informa Healthcare USA, Inc.

Guimaraes L.B.D.M.,Federal University of Rio Grande do Sul
Work | Year: 2012

This article presents a literature review on the concept of sustainability applied to cities and a proposal for transforming a town in the south of Brazil into a sustainable town. Improvements in energy, sanitation, waste and water conditions, as well as food, clothing, education and jobs generation were considered to enhance the citizen's quality of life and environmental protection. © 2012 - IOS Press and the authors. All rights reserved.

Pfefferkorn H.W.,University of Pennsylvania | Alleman V.,Ricardo Palma University | Iannuzzi R.,Federal University of Rio Grande do Sul
Gondwana Research | Year: 2014

The late Paleozoic ice age (LPIA) is the closest example that can be compared with current climate conditions. Near the beginning of the LPIA fossil plants of Mississippian (late Visean to earliest Serpukhovian) age indicate a widespread frost-free climate in a wide belt on Gondwana indicating an interval of greenhouse conditions between the earlier Visean and later Serpukhovian icehouse times. This warm-temperate floral belt has been named the Paraca floral belt after the locality on the Peruvian coast where it was first recognized. The origin of this particular zono-biome was due to the interplay of (1) climate oscillations, (2) several kinds of long-distance plant dispersal within, between or through zono-biomes, and (3) plate motion. The Carboniferous age strata on the Paracas Peninsula in Peru serve as an example for an analysis of these large scale patterns through the analysis of local geology, paleobotany, and paleoecology. The processes observed during this time interval can serve as a model for long-distance plant dispersal at other times. © 2013 International Association for Gondwana Research.

The literature and experience of working in primary health care allowed the author to reflect on the main features of the matricial practices of health care networks in the context of the SUS over the years. Matricial practice current notion seems to put forward consulting practices and supervision by teams or professionals to whom the quality of experts is assigned. The effects of this relationship between teams and services are discussed and the benefits in the context of management and health care are analyzed. Sustained in the original proposal of matricial practice, the article establishes a problematization that derives logical consequences to build a notion that is different from that sustained the barren relationship between specialists and generalists. With the support of the mathematical theory of matrix calculus, it builds the concept of matricial practice that could contribute to implement collaborative relationships between teams and services with important and resolving effects in the field of care and management of comprehensive health care. © 2015, Institute de Medicina Social da UERJ. All rights reserved.

The multi-professional residence at the primary health care is part of a network of training in education and health in Brazil that has been expanded in the last decade. Training within health services aims to prepare professionals to work in the Health National System. This article examines how workers and residents experience educational processes in the Program of Integrated Health Residency: Primary Care in Public Health, developed in basic health units belonging, up to 2009, to the Murialdo Health School-Center, and linked to Rio Grande do Sul School of Public Health. This is a qualitative research whose methodological course has input into cultural studies in approach to post-modern ethnography. The fieldwork was conducted from March 2007 to April 2008 and empirical data included educational and administrative documents institutions, relevant legislation to the regulation of residency programs, reports of residents, direct observation of teams and interviews with health workers. To reflect on the limitations and possibilities of this training, the writings of Bauman about the cultural characteristics of "liquid modernity" were used, because the context was marked by tentativeness and uncertainty, which produce potentialities and vulnerabilities in the residency program. © 2015, Institute de Medicina Social da UERJ. All Rights Reserved.

Rodnight R.B.,Hunter Medical Research Institute | Gottfried C.,Federal University of Rio Grande do Sul
Journal of Neurochemistry | Year: 2013

In the past two decades, there has been an explosion of research on the role of neuroglial interactions in the control of brain homeostasis in both physiological and pathological conditions. Astrocytes, a subtype of glia in the central nervous system, are dynamic signaling elements that regulate neurogenesis and development of brain circuits, displaying intimate dynamic relationships with neurons, especially at synaptic sites where they functionally integrate the tripartite synapse. When astrocytes are isolated from the brain and maintained in culture, they exhibit a polygonal shape unlike their precursors in vivo. However, cultured astrocytes can be induced to undergo morphological plasticity leading to process formation, either by interaction with neurons or by the influence of pharmacological agents. This review highlights studies on the molecular mechanisms underlying morphological plasticity in astrocyte cultures and intact brain tissue, both in situ and in vivo. © 2012 International Society for Neurochemistry.

MacHado M.V.T.,Federal University of Rio Grande do Sul | Da Silva M.L.L.,Federal University of Santa Catarina
Physical Review C - Nuclear Physics | Year: 2011

The cross sections for the glueball candidates in quasireal photon-photon collisions and on central diffraction processes (i.e., double Pomeron exchange) in heavy-ion interactions at the Relativistic Heavy-Ion Collider (RHIC) and the Large Hadron Collider (LHC) are computed. The rates for these distinct production channels are compared, and they may be a fruitful approach to the investigation of glueballs. © 2011 The American Physical Society.

Guidoti M.,Federal University of Rio Grande do Sul | Barcellos A.,Museu de Ciencias Naturais
Zootaxa | Year: 2013

The five instars of Teleonemia scrupulosa Stal are described. The postembryonic ontogenetic development of integumentary structures is emphasized, with a discussion on its potential use in cladistic studies within Tingidae. © 2013 Magnolia Press.

Dietrich M.O.,Yale University | Dietrich M.O.,Federal University of Rio Grande do Sul | Horvath T.L.,Yale University
Pflugers Archiv European Journal of Physiology | Year: 2010

The increased longevity in modern societies raised the attention to biological interventions that could promote a healthy aging. Mitochondria are main organelles involved in the production of adenosine triphosphate (ATP), the energetic substrate for cellular biochemical reactions. The production of ATP occurs through the oxidative phosphorylation of intermediate substrates derived from the breakdown of lipids, sugars, and proteins. This process is coupled to production of oxygen reactive species (ROS) that in excess will have a deleterious role in cellular function. The damage promoted by ROS has been emphasized as one of the main processes involved in senescence. In the last decades, the discovery of specialized proteins in the mitochondrial inner membrane that promote the uncoupling of proton flux (named uncoupling proteins-UCPs) from the ATP synthase shed light on possible mechanisms implicated in the buffering of ROS and consequently in the process of aging. UCPs are responsible for a physiological uncoupling that leads to decrease in ROS production inside the mitochondria. Thus, induction of uncoupling through UCPs could decrease the cellular damage that occurs during aging due to excess of ROS. This review will focus on the evidence supporting these mechanisms. © 2009 Springer-Verlag.

Goncalves V.P.,Federal University of Pelotas | MacHado M.V.T.,Federal University of Rio Grande do Sul
Physical Review C - Nuclear Physics | Year: 2011

In this Rapid Communication we update our predictions for the photoproduction of vector mesons in coherent pp and AA collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies using the color dipole approach and the Color Glass Condensate formalism. In particular, we present our predictions for the first run of the LHC at half energy and for the rapidity dependence of the ratio between the J/Ψ and ρ cross sections at RHIC energies. © 2011 American Physical Society.

Nascimento M.A.,University of Sao Paulo | Gallas J.A.C.,Federal University of Paraiba | Gallas J.A.C.,Federal University of Rio Grande do Sul | Varela H.,University of Sao Paulo
Physical Chemistry Chemical Physics | Year: 2011

We report a detailed numerical investigation of a prototype electrochemical oscillator, in terms of high-resolution phase diagrams for an experimentally relevant section of the control (parameter) space. The prototype model consists of a set of three autonomous ordinary differential equations which captures the general features of electrochemical oscillators characterized by a partially hidden negative differential resistance in an N-shaped current-voltage stationary curve. By computing Lyapunov exponents, we provide a detailed discrimination between chaotic and periodic phases of the electrochemical oscillator. Such phases reveal the existence of an intricate structure of domains of periodicity self-organized into a chaotic background. Shrimp-like periodic regions previously observed in other discrete and continuous systems were also observed here, which corroborate the universal nature of the occurrence of such structures. In addition, we have also found a structured period distribution within the order region. Finally we discuss the possible experimental realization of comparable phase diagrams.

Azoulay J.D.,University of California at Santa Barbara | Bazan G.C.,University of California at Santa Barbara | Galland G.B.,Federal University of Rio Grande do Sul
Macromolecules | Year: 2010

A nickel α-keto-β-diimine initiator (1), when activated with methylaluminoxane (MAO) generates active sites capable of polymerizing a-olefins to high molecular weight products. Herein, we report on the full characterization and detailed microstructural analysis of poly(1-hexene) (PH) homopolymers obtained by using the 1/MAO combination. 13C NMR spectroscopy was used to provide the first qualitative and quantitative determinations of all the sequences in the poly(1-hexene). Such information yields insight into the reactivity of this novel catalytic system. © 2010 American Chemical Society.

Spritzer P.M.,Gynecologic Endocrinology Unit | Spritzer P.M.,Federal University of Rio Grande do Sul
Arquivos Brasileiros de Endocrinologia e Metabologia | Year: 2014

Polycystic ovary syndrome (PCOS) is a common condition in women at reproductive age associated with reproductive and metabolic dysfunction. Proposed diagnosed criteria for PCOS include two out of three features: androgen excess, menstrual irregularity, and polycystic ovary appearance on ultrasound (PCO), after other causes of hyperandrogenism and dysovulation are excluded. Based on these diagnostic criteria, the most common phenotypes are the "classic PCOS" - hyperandrogenism and oligomenorrhea, with or without PCO; the "ovulatory phenotype" - hyperandrogenism and PCO in ovulatory women; and the "non-hyperandrogenic phenotype", in which there is oligomenorrhea and PCO, without overt hyperandrogenism. The presence of obesity may exacerbate the metabolic and reproductive disorders associated with the syndrome. In addition, PCOS women present higher risk for type 2 diabetes and higher prevalence of cardiovascular risk factors that seems to be associated with the classic phenotype. The main interventions to minimize cardiovascular and metabolic risks in PCOS are lifestyle changes, pharmacological therapy, and bariatric surgery. Treatment with metformin has been shown to improve insulin sensitivity, lowering blood glucose and androgen levels. These effects are more potent when combined with lifestyle interventions. In conclusion, besides reproductive abnormalities, PCOS has been associated to metabolic comorbidities, most of them linked to obesity. Confounders, such as the lack of standard diagnostic criteria, heterogeneity of the clinical presentation, and presence of obesity, make management of PCOS difficult. Therefore, the approach to metabolic abnormalities should be tailored to the risks and treatment goals of each individual woman. © ABE&M todos os direitos reservados.

Marchant C.,University of Valparaiso | Bertin K.,University of Valparaiso | Leiva V.,University of Valparaiso | Saulo H.,Federal University of Rio Grande do Sul
Computational Statistics and Data Analysis | Year: 2013

The kernel method is a nonparametric procedure used to estimate densities with support in R. When nonnegative data are modeled, the classical kernel density estimator presents a bias problem in the neighborhood of zero. Several methods have been developed to reduce this bias, which include the boundary kernel, data transformation and reflection methods. An alternative proposal is to use kernel estimators based on distributions with nonnegative support, as is the case of the Birnbaum-Saunders (BS), gamma, inverse Gaussian and lognormal models. Generalized BS (GBS) distributions have received considerable attention, due to their properties and their flexibility in modeling different types of data. In this paper, we propose, characterize and implement the kernel method based on GBS distributions to estimate densities with nonnegative support. In addition, we provide a simple method to choose the corresponding bandwidth. In order to evaluate the performance of these new estimators, we conduct a Monte Carlo simulation study. The obtained results are illustrated by analyzing financial real data. © 2013 Elsevier B.V. All rights reserved.

Vos M.,Australian National University | Grande P.L.,Australian National University | Grande P.L.,Federal University of Rio Grande do Sul | Venkatachalam D.K.,Australian National University | And 3 more authors.
Physical Review Letters | Year: 2014

High-resolution measurement of the energy of electrons backscattered from oxygen atoms makes it possible to distinguish between O18 and O16 isotopes as the energy of elastically scattered electrons depends on the mass of the scattering atom. Here we show that this approach is suitable for measuring oxygen self-diffusion in HfO2 using a HfO162(20nm)/HfO182 bilayers (60 nm). The mean depth probed (for which the total path length equals the inelastic mean free path) is either 5 or 15 nm in our experiment, depending on the geometry used. Before annealing, the elastic peak from O is thus mainly due to electrons scattered from O16 in the outer layer, while after annealing the signal from O18 increases due to diffusion from the underlying HfO182 layer. For high annealing temperatures the observed interdiffusion is consistent with an activation energy of 1 eV, but at lower temperatures interdiffusion decreases with increasing annealing time. We interpret this to be a consequence of defects, present in the layers early on and enhancing the oxygen diffusivity, disappearing during the annealing process. © 2014 American Physical Society.

Jerep F.C.,Grande Rio University | Malabarba L.R.,Federal University of Rio Grande do Sul
Neotropical Ichthyology | Year: 2011

The cheirodontine genus Macropsobrycon is redefined and considered monotypic. The type species, M. uruguayanae, is redescribed based on samples from the entire known geographical distribution of the species. Sexually dimorphic characters of M. uruguayanae are further described and the relationships of the species with the remaining Compsurini are discussed. © 2011 Sociedade Brasileira de Ictiologia.

Bisol L.W.,Federal University of Rio Grande do Sul | Lara D.R.,Pontifical Catholic University of Rio Grande do Sul
Journal of Psychopharmacology | Year: 2010

Patients with hyperthymic and cyclothymic temperaments often develop symptoms that fail to meet diagnostic criteria for bipolar disorders. These patients can be conceived as having bipolar disorder NOS (not otherwise specified), a bipolar spectrum disorder, cyclothymic disorder or cluster B personality traits. Here, we describe four of these patients with mild to moderate symptoms affecting mood, behaviour, emotional reactivity and sleep. Treatment with low-dose quetiapine (25-75 mg/day at night) lead to sustained symptom remission. Two of them were on quetiapine monotherapy. Such low doses occupy a minority of D2 and 5-HT2 receptors, which may nevertheless be of therapeutic value in mild cases. Alternatively, other mechanisms more likely to occur at low doses, such as antagonism of H1, α(1B)-adrenergic and other serotonin receptors, as well as reduction Cortisol secretion, may be involved in the therapeutic efficacy of quetiapine. © 2010 British Association for Psychopharmacology.

Higgins M.J.,Harvard University | Liedke P.E.R.,Harvard University | Liedke P.E.R.,Federal University of Rio Grande do Sul | Goss P.E.,Harvard University
Critical Reviews in Oncology/Hematology | Year: 2013

Early hormone-receptor-positive breast cancer is a chronic relapsing disease that can remain clinically silent for many years. The NCIC-CTG MA.17/BIG 1-97 trial randomized disease-free early breast cancer patients who had received five years of adjuvant tamoxifen to either letrozole or placebo and was the first to demonstrate a benefit with extended endocrine therapy. MA.17/BIG 1-97 was stopped at the first interim analysis because disease free survival was strongly prolonged in the letrozole arm. Subsequent subset analyses and longer follow up have shown that this therapy improved survival across all groups, particularly among women with node-positive disease and those that were pre-menopausal at time of study enrolment. The MA.17/BIG 1-97 study should be considered a paradigm for extended adjuvant endocrine therapy in hormone-receptor-positive early breast cancer. © 2012 Elsevier Ireland Ltd.

Ferreira L.,Federal University of Rio Grande do Norte | Borenstein D.,Federal University of Rio Grande do Sul
Journal of the Operational Research Society | Year: 2011

This paper presents an agent-based simulation framework for supply chain (SC) planning, introducing the notion of normative agent. The analysis of the relevant literature shows that most research works carried out in this area aim to handle specific problems and contexts. Although some methodologies and more generic solutions have been proposed, they are not able to cope with SCs in which regulation plays an important role, whether issued by a government agent or by an international institution. Several SCs, such as in the energy, food, chemical, and forestry areas, are highly regulated. Explicitly modelling the actors involved in the regulation of SCs using normative agents allowed us to evaluate the potential benefits of alternative strategies for planning of regulated SCs. The modelling of a biodiesel SC is presented as a case study. © 2011 Operational Research Society Ltd. All rights reserved.

The use of psychotropic drugs is on the increase, and there are few studies in Brazil investigating their use in the population and in Primary Health Care (PHC). This study aimed to determine the prevalence and patterns of psychotropic drug use by patients of a Family Health Unit in Porto Alegre, through an observational, descriptive, retrospective and cross-sectional study. The sample consisted of patients who received prescriptions for controlled psychotropic drugs and the data collected from medical records. The study included 329 patients, with prevalence of the use of psychotropic drugs of 7.30%, mean age of 53.14 (SD = 18.58) years and 72% female. The average number of prescribed drugs and psychotropic drugs per user was 3.56 (SD = 2.36) and 1.66 (SD = 0.90), respectively. The most widely used class was antidepressants, followed by antiepileptics, anxiolytics and antipsychotics. It is necessary to develop strategies to improve access, treatment of patients and rational use of psychotropic drugs, including the revision of lists of essential drugs and training of professionals in PHC.

Frydel D.,Federal University of Rio Grande do Sul
Journal of Chemical Physics | Year: 2011

We incorporate ion polarizabilities into the Poisson-Boltzmann equation by modifying the effective dielectric constant and the Boltzmann distribution of ions. The extent of the polarizability effects is controlled by two parameters, 1 and 2; 1 determines the polarization effects in a dilute system and 2 regulates the dependence of the polarizability effects on the concentration of ions. For a polarizable ion in an aqueous solution 1 ≈ 0.01 and the polarizability effects are negligible. The conditions where 1 and/or 2 are large and the polarizability is relevant involve the low dielectric constant media, high surface charge, and/or large ionic concentrations. © 2011 American Institute of Physics.

Marczak R.J.,Federal University of Rio Grande do Sul
Latin American Journal of Solids and Structures | Year: 2015

This work reviews the developments of Boundary Element Method formulations to solve several types of plate bending problems, including non-linear bending. The formulation is developed and solved using the standard BEM procedure, and different integration approaches were discussed and tested. Object oriented implementation issues are commented. Results were obtained for linear and non-linear elastic bending as well as buckling of selected cases of thick plates, including cases of step variation in thickness under large displacements regime. © 2015, Brazilian Association of Computational Mechanics.All right reserved.

Lorenzini G.,University of Parma | Biserni C.,University of Bologna | Rocha L.A.O.,Federal University of Rio Grande do Sul
International Journal of Thermal Sciences | Year: 2013

This paper applies constructal design to discover the configuration that facilitates the access of the heat that flows through non-uniform X-shaped pathways of high-conductivity material embedded within a square-shaped heat-generating medium of low-conductivity to cooling this finite-size volume. The objective is to minimize the maximal excess of temperature of the whole system, i.e. the hot spots, independent of where they are located. The total volume and the volume of the material of high thermal conductivity are fixed, but the lengths of the pathways and the angles between the pathways can vary. The configuration was optimized for four degrees of freedom: the two angles between the pathways, and the two ratios between the lengths. It was found numerically that the performance of the non-uniform X-shaped pathways is approximately 10% better than the performance of the uniform X-shaped pathways, i.e. X-shaped with equal lengths and thicknesses. When compared to the configuration calculated for a simpler I-shaped blade (i.e. a single pathway of high thermal conductivity material beginning in the isothermal wall and ending of such a way that there is spacing between the tip of the pathway and the insulated wall) the non-uniform X-shaped pathways configuration performs 56% better. © 2013 Elsevier Masson SAS. All rights reserved.

Wouters A.D.,University of Sao Paulo | Ludtke D.S.,University of Sao Paulo | Ludtke D.S.,Federal University of Rio Grande do Sul
Organic Letters | Year: 2012

The diastereoselective arylation of sugar-derived aldehydes is described. The arylating reagents are generated in situ by a boron-to-zinc exchange reaction of arylboronic acids with Et2Zn to generate arylethylzinc reagents. The exquisite reactivity of the arylzinc reagents allowed for an efficient and mild arylation, delivering the corresponding products in diastereoisomeric ratios of up to >20:1. The utility of the methodology is highlighted with an efficient formal synthesis of (+)-7-epi-goniofufurone, a member of the styryllactone family of natural products. © 2012 American Chemical Society.

Xavier R.,Federal University of Rio Grande do Sul
Revista em Agronegocio e Meio Ambiente | Year: 2016

The rice sector in Brazil and Uruguay is compared. Uruguay has excellent results in rice cultivation and may be an example for Brazil. In fact, Brazil must invest better to improve rice production. Current study analyzes the relationship between the production factors in rice productivity in Brazil and Uruguay. Further, it also investigates guidelines and institutional incentives that enhance productivity in the rice sector in both countries by comparing them. Current descriptive study investigates two cross country comparative cases. Quality and quantity data were employed by simple linear regression. Results suggest that integrated policies in Uruguay and the use of technology are important factors for competitiveness. Money lent is not sufficient to improve yield in Brazil. The study shows several important weaknesses. Evidence sources are limited; data for one year were consulted; such factors as climate and water resources which highly effect rice cultivation have not been taken into account.

Doff A.,Federal Technological University of Parana | Luna E.G.S.,Federal University of Rio Grande do Sul | Natale A.A.,Federal University of ABC | Natale A.A.,Sao Paulo State University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

Assuming that the 125 GeV particle observed at the LHC is a composite scalar and responsible for the electroweak gauge symmetry breaking, we consider the possibility that the bound state is generated by a non-Abelian gauge theory with dynamically generated gauge boson masses and a specific chiral symmetry breaking dynamics motivated by confinement. The scalar mass is computed with the use of the Bethe-Salpeter equation and its normalization condition as a function of the SU(N) group and the respective fermionic representation. If the fermions that form the composite state are in the fundamental representation of the SU(N) group, we can generate such a light boson only for one specific number of fermions for each group. We address the uncertainties underlying this result, when considering the strong dynamics in isolation. © 2013 American Physical Society.

Haag K.L.,University of Basel | Haag K.L.,Federal University of Rio Grande do Sul | James T.Y.,University of Michigan | Pombert J.-F.,Illinois Institute of Technology | And 5 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Intracellular parasitism results in extreme adaptations, whose evolutionary history is difficult to understand, because the parasites and their known free-living relatives are so divergent from one another. Microsporidia are intracellular parasites of humans and other animals, which evolved highly specialized morphological structures, but also extreme physiologic and genomic simplification. They are suggested to be an early-diverging branch on the fungal tree, but comparisons to other species are difficult because their rates of molecular evolution are exceptionally high. Mitochondria in microsporidia have degenerated into organelles called mitosomes, which have lost a genome and the ability to produce ATP. Here we describe a gut parasite of the crustacean Daphnia that despite having remarkable morphological similarity to the microsporidia, has retained genomic features of its fungal ancestors. This parasite, which we name Mitosporidium daphniae gen. et sp. nov., possesses a mitochondrial genome including genes for oxidative phosphorylation, yet a spore stage with a highly specialized infection apparatus - the polar tube - uniquely known only from microsporidia. Phylogenomics places M. daphniae at the root of the microsporidia. A comparative genomic analysis suggests that the reduction in energy metabolism, a prominent feature of microsporidian evolution, was preceded by a reduction in the machinery controlling cell cycle, DNA recombination, repair, and gene expression. These data show that the morphological features unique to M. daphniae and other microsporidia were already present before the lineage evolved the extreme host metabolic dependence and loss of mitochondrial respiration for which microsporidia are well known. © 2014, National Academy of Sciences. All rights reserved.

Based on recently published research findings on abortion rates, this paper re-examines original ethnographic data on abortion in order to open a discussion on the dissemination of abortion, its possible cultural configurations and its social legitimacy among low-income populations in Brazil. It refers retrospectively to two works of empirical research studies and presents an estimate of the prevalence of abortion of around of 34%; it describes abortion practices and the social representation of what abortion means in a given context. The studies presented here seek to contribute to the understanding of women's decision-making regarding this reproductive choice in a context where abortion is illegal. The data allow us to construct an abortion typology, classifying it as tolerated, unacceptable and recommended and point to a fluidity of meanings regarding pregnancy interruption practices. It is possible to infer that the magnitude of the problem of abortion, both with regard to number of cases and the existing diversity of abortion practices and methods, has not changed over a period of 20 years in Brazil.

Rupture of vasa varorum has been recognized as one cause of intramural hematoma of the aorta for 90 years. This brief revision presents systematically, the physiology of these vessels and its role in the physiopathology of the alterations in the aortic wall secondary to hypertension, arteriosclerosis and in Acute Aortic Syndrome. The hypothesis is that rupture of vasa vasorum is a secondary phenomenon and not one causal factor in the physiopathology of intramural hematoma.

Suarez-Kurtz G.,Instituto Nacional do Cancer | Pena S.D.,Federal University of Minas Gerais | Hutz M.H.,Federal University of Rio Grande do Sul
Pharmacogenomics | Year: 2012

Background: New drug applications submitted to regulatory agencies in developing countries rarely include data from local clinical trials. We used the FST statistics to explore the pharmacogenomic diversity of the Brazilian population and its potential implications in drug regulatory assessment and decisions. Methods: The FST analyses were based on data for 44 polymorphisms in 12 pharmacogenes among 1034 healthy Brazilians, recruited in four different geographical regions and self-identified as branco (white) pardo (brown) or preto (black). Each region/color group comprised 83-89 individuals. The Utah residents of northern and western European ancestry and Yoruba people from Nigeria, Africa, cohorts of the HapMap project were used as proxies of the European and sub-Saharan African ancestral roots of Brazilians, respectively. Results: Allele-specific FST values for the overall Brazilian cohort revealed low genetic divergence between white and brown (F ST = 0.005 ± 0.006, mean ± standard deviation), white and black (0.013 ± 0.017) and brown and black (0.004 ± 0.005) individuals. However, the distribution of FST values for white vs brown (p < 0.0001, analysis of variance) and white vs black (p < 0.0001) differed significantly across the geographical regions. Considerably larger pharmacogenomic divergence was observed between black Brazilians and Yoruba people from Nigeria, Africa (FST = 0.028 ± 0.035) compared to white Brazilians vs Utah residents of northern and western European ancestry (0.007 ± 0.010). Conclusion: The present FST analyses highlight the challenge faced by Brazilian regulatory agencies when assessing the relevance to Brazilians of pharmacogenomic data derived from foreign populations, with distinct biogeographical ancestries. This challenge is compounded by the heterogeneity of the Brazilian population with respect to the frequency distribution of pharmacogenomic polymorphisms across color categories and geographical regions. © 2012 Future Medicine Ltd.

Podgaiski L.R.,Federal University of Rio Grande do Sul | Rodrigues G.G.,Federal University of Pernambuco
European Journal of Soil Biology | Year: 2010

We studied the leaf-litter decomposition of three pioneer plants (Cynodon dactylon - grass; Ricinus communis - shrub and Schinus terebinthifolius - tree), and the diversity of the associated detritivore macrofaunal assemblages in a system affected by two coal ash disposals (fly ash and boiler slag) in southern Brazil. We conducted a litter bag experiment in the area during a period of 140 days. We found that the decomposition rate of R. communis was more than 80% faster (k-value 20.7) than the other species. This result agrees with its low C:N ratio, high N (%), and increased abundance of detritivores in the first days of its decomposition. On the other hand, this leaf-litter supported the lowest invertebrate species richness. C. dactylon and S. terebinthifolius leaf-litters were similar in decomposition rates and macrofauna diversity. The type of ash disposal system did not affect leaf-litter decomposition and detritivore densities; on the other hand, the morphospecies composition was distinct in the different sites. © 2010 Elsevier Masson SAS.

Bogusz S.,University of Campinas | de Marchi Tavares de Melo A.,Campinas Agronomic institute IAC | Zini C.A.,Federal University of Rio Grande do Sul | Godoy H.T.,University of Campinas
Journal of Chromatography A | Year: 2011

A method involving headspace-solid phase micro-extraction (HS-SPME), gas chromatography with flame ionization detection (GC-FID) and gas chromatography with mass spectrometry (GC-MS) was developed and optimized to investigate the volatile composition of Capsicum chili peppers. Five SPME fibers were tested for extraction: carboxen/polydimethylsiloxane (CAR/PDMS-75. μm), polydimethylsiloxane (PDMS-100. μm), divinylbenzene/polydimethylsiloxane (DVB/PDMS-65. μm), carbowax/divinylbenzene (CW/DVB-70. μm), and divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS-50/30. μm), the last of which was shown to be the most efficient fiber to trap the volatile compounds. Optimization of the extraction conditions was carried out using multivariate strategies such as factorial design and response surface methodology. Eighty three compounds were identified by GC-MS when using the optimized extraction conditions, the majority of which were esters. © 2011 Elsevier B.V.

Ganganagappa N.,Federal University of Rio Grande do Sul | Siddaramanna A.,Indian Institute of Science
Materials Characterization | Year: 2012

One of the metastable phases of vanadium dioxide, VO 2(B) bundles of nanorods and microspheres have been synthesized through a simple hydrothermal method by dispersing V 2O 5 in aqueous quinol. The obtained products were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and electrochemical discharge-charge test for lithium battery. It was found that the morphologies of the obtained VO 2(B) can be tuned by manipulating the relative amount of quinol. The electrochemical test found that the bundles of nanorods exhibit an initial discharge capacity of 171 mAh g - 1 and its almost stabilized capacity was reached to 108 mAh g - 1 after 47 cycles at a current density of 0.1 mA g - 1. The formation mechanism of the VO 2(B) bundles of nanorods and microspheres was also discussed. © 2012 Elsevier Inc. All rights reserved.

Ligeiro R.,Federal University of Minas Gerais | Melo A.S.,Federal University of Rio Grande do Sul | Melo A.S.,Federal University of Goais | Callisto M.,Federal University of Minas Gerais
Freshwater Biology | Year: 2010

Lotic ecosystems can be studied on several spatial scales, and usually show high heterogeneity at all of them in terms of biological and environmental characteristics. Understanding and predicting the taxonomic composition of biological communities is challenging and compounded by the problem of scale. Additive diversity partitioning is a tool that can show the diversity that occurs at different scales. We evaluated the spatial distribution of benthic macroinvertebrates in a tropical headwater catchment (S.E. Brazil) during the dry season and compared alpha and beta diversities at the scales of stream segments, reaches, riffles and microhabitats (substratum types: gravels, stones and leaf litter). We used family richness as our estimate of diversity. Sampling was hierarchical, and included three stream segments, two stream reaches per segment, three riffles per reach, three microhabitats per riffle and three Surber sample units per microhabitat. Classification analysis of the 53 families found revealed groups formed in terms of stream segment and microhabitat, but not in terms of stream reaches and riffles. Separate partition analyses for each microhabitat showed that litter supported lower alpha diversity (28%) than did stones (36%) or gravel (42%). In all cases, alpha diversity at the microhabitat scale was lower than expected under a null model that assumed no aggregation of the fauna. Beta diversity among patches of the microhabitats in riffles depended on substratum type. It was lower than expected in litter, similar in stone and higher in gravel. Beta diversities among riffles and among reaches were as expected under the null model. On the other hand, beta diversity observed was higher than expected at the scale of stream segments for all microhabitat types. We conclude that efficient diversity inventories should concentrate sampling in different microhabitats and stream sites. In the present study, sampling restricted to stream segments and substratum types (i.e. excluding riffles and stream reaches) would produce around 75% of all observed families using 17% of the sampling effort employed. This finding indicates that intensive sampling (many riffles and reaches) in few stream segments does not result in efficient assessment of diversity in a region. © 2009 Blackwell Publishing Ltd.

Scholten J.D.,Federal University of Rio Grande do Sul
Current Organic Chemistry | Year: 2013

This review will intend to cover the main examples on the use of soluble and supported iridium metal nanoparticles as effective catalysts for hydrogenation of different substrates in conventional reaction medium, such as water, organic solvents, and ionic liquids. Some aspects involving the synthesis of these nanocatalysts will be also discussed in details. © 2013 Bentham Science Publishers.

Kvitko C.H.,Federal University of Rio Grande do Sul | Rigatto M.H.,Grande Rio University | Moro A.L.,Grande Rio University | Zavascki A.P.,Grande Rio University
Journal of Antimicrobial Chemotherapy | Year: 2011

Objectives: To compare the efficacy of intravenous polymyxin B with other antimicrobials in the treatment of nosocomial Pseudomonas aeruginosa bacteraemia, assessing many potential confounding factors, including optimal dosage regimens of drugs. Methods: A retrospective cohort study was performed. Patients ≥18 years of age and who received appropriate therapy for ≥48 h for P. aeruginosa bacteraemia were analysed. Clinical covariates were assessed and compared between patients treated with polymyxin B and other drugs (comparators). Data were retrieved from medical records. Renal toxicity was also assessed. A Cox regression model was performed including variables with a P≤0.20 in the comparison between both groups. Results: A total of 133 patients were included: 45 (33.8%) treated with polymyxin B and 88 (66.2%) with comparators. Most comparators (83.0%) were β-lactams. The overall in-hospital mortality was 41.4% (55/133): 66.7% (30/45) and 28.4% (25/88) in polymyxin B and comparator groups, respectively (P≤0.001). The final multivariate model showed that treatment with polymyxin B was independently associated with in-hospital mortality (adjusted hazard ratio 1.91, 95% confidence interval 1.05-3.45), after adjustment for Pitt bacteraemia score, and the presence of mechanical ventilation and primary bloodstream infection. Patients treated with polymyxin B presented a higher rate of ≥100% increase in creatinine level from baseline than comparators [11/45 (24.4%) versus 4/88 (4.5%); P=0.002], although this was not subjected to multivariate analysis. Conclusions: Intravenous polymyxin B therapy was inferior to other drugs in the treatment of P. aeruginosa bacteraemia, as indicated by the higher rate of in-hospital mortality. © The Author 2010. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.

Barbosa O.,Industrial University of Santander | Ortiz C.,Industrial University of Santander | Berenguer-Murcia A.,University of Alicante | Torres R.,Industrial University of Santander | And 2 more authors.
RSC Advances | Year: 2014

Glutaraldehyde is one of the most widely used reagents in the design of biocatalysts. It is a powerful crosslinker, able to react with itself, with the advantages that this may bring forth. In this review, we intend to give a general vision of its potential and the precautions that must be taken when using this effective reagent. First, the chemistry of the glutaraldehyde/amino reaction will be commented upon. This reaction is still not fully clarified, but it seems to be based on the formation of 6-membered heterocycles formed by 5 C and one O. Then, we will discuss the production of intra- and inter-molecular enzyme crosslinks (increasing enzyme rigidity or preventing subunit dissociation in multimeric enzymes). Special emphasis will be placed on the preparation of cross-linked enzyme aggregates (CLEAs), mainly in enzymes that have low density of surface reactive groups and, therefore, may be problematic to obtain a final solid catalyst. Next, we will comment on the uses of glutaraldehyde in enzymes previously immobilized on supports. First, the treatment of enzymes immobilized on supports that cannot react with glutaraldehyde (only inter and intramolecular cross-linkings will be possible) to prevent enzyme leakage and obtain some enzyme stabilization via cross-linking. Second, the cross-linking of enzymes adsorbed on aminated supports, where together with other reactions enzyme/support crosslinking is also possible; the enzyme is incorporated into the support. Finally, we will present the use of aminated supports preactivated with glutaraldehyde. Optimal glutaraldehyde modifications will be discussed in each specific case (one or two glutaraldehyde molecules for amino group in the support and/or the protein). Using preactivated supports, the heterofunctional nature of the supports will be highlighted, with the drawbacks and advantages that the heterofunctionality may have. Particular attention will be paid to the control of the first event that causes the immobilization depending on the experimental conditions to alter the enzyme orientation regarding the support surface. Thus, glutaraldehyde, an apparently old fashioned reactive, remains the most widely used and with broadest application possibilities among the compounds used for the design of biocatalyst. © 2014 The Royal Society of Chemistry.

Grande P.L.,Australian National University | Grande P.L.,Federal University of Rio Grande do Sul | Vos M.,Australian National University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

The energy loss of fast ions at close collision is mainly due to electron-ion collisions. The electrons are approximately stationary and they collide with a fast-moving ion. Here we study the same collision experimentally, in a reference system where the ions (or atoms) are stationary and interacting with keV electrons. Scattering cross sections under these conditions deviate from Rutherford, and we link these deviations, at higher energies, to the Z3 contributions to the electronic stopping and the related Barkas effect and, at lower energies, also to quantum interference. The present measurements are well described by partial-wave calculations of the elastic cross section of electrons scattering from atoms. Encouraged by this agreement we use these calculations to estimate the Barkas factor for all elements and many energies. A universal curve for the Barkas factor due to close collisions is obtained for neutral projectiles and similar curves with smaller magnitude are found for ions. © 2013 American Physical Society.

Da S. Rosa P.R.,Federal University of Mato Grosso | Ziebell L.F.,Federal University of Rio Grande do Sul
Nuclear Fusion | Year: 2010

In this paper we discuss the role played by a radiofrequency induced electric field on the current drive efficiency of electron cyclotron (EC) waves when there are locked or rotating magnetic islands in the plasma. The problem is addressed by numerical solution of the Fokker-Planck equation within the framework of the quasilinear theory incorporating realistic features of the geometry of the magnetic islands. The modes 2/1 and 3/2 are analysed. Our main result is the reduction, although not the complete suppression, of the level of the current driven by the waves in the short time scale needed for the induced field to diffuse away from the islands region. Another finding is the suppression of quasilinear effects on the EC current drive efficiency in the case of locked islands for both 2/1 and 3/2 modes. © 2010 IOP Publishing Ltd.

Esteves R.P.,Federal University of Rio Grande do Sul | Granville L.Z.,University of Waterloo | Boutaba R.,University of Waterloo
IEEE Communications Magazine | Year: 2013

Network virtualization is a feasible solution to tackle so-called Internet ossification by enabling the deployment of novel network architectures in a flexible and controlled way. With network virtualization, it is possible to have multiple virtual networks running simultaneously on top of a shared physical infrastructure. Network management with virtualization support, however, poses challenges that need to be addressed in order to fully achieve an effective and reliable networking environment. These challenges have motivated the investigation of novel management solutions in recent years. This article surveys some of the prominent solutions for network virtualization management and identifies research opportunities in the area. © 1979-2012 IEEE.

Dupont J.,Federal University of Rio Grande do Sul | Eberlin M.N.,University of Campinas
Current Organic Chemistry | Year: 2013

This review provides an overview of the use of mass spectrometry (MS) and its various ionization techniques and an evaluation of their suitability to investigate structures and physico-chemical properties of ionic liquids (IL) and the types of information that can be obtained from such experiments. We will focus on most representative and comprehensive work, and on the work that we are been performing in an collaboration involving our laboratories, one devoted to the synthesis and uses of IL and to the other to the development of new MS techniques and their applications. © 2013 Bentham Science Publishers.

Blaser R.E.,University of San Diego | Rosemberg D.B.,Federal University of Rio Grande do Sul | Rosemberg D.B.,Instituto Nacional Of Ciencia E Tecnologia Em Excitotoxicidade E Neuroprotecao Inct En
PLoS ONE | Year: 2012

The effects of wall color stimuli on diving, and the effects of depth stimuli on scototaxis, were assessed in zebrafish. Three groups of fish were confined to a black, a white, or a transparent tank, and tested for depth preference. Two groups of fish were confined to a deep or a shallow tank, and tested for black-white preference. As predicted, fish preferred the deep half of a split-tank over the shallow half, and preferred the black half of a black/white tank over the white half. Results indicated that the tank wall color significantly affected depth preference, with the transparent tank producing the strongest depth preference and the black tank producing the weakest preference. Tank depth, however, did not significantly affect color preference. Additionally, wall color significantly affected shuttling and immobility, while depth significantly affected shuttling and thigmotaxis. These results are consistent with previous indications that the diving response and scototaxis may reflect dissociable mechanisms of behavior. We conclude that the two tests are complementary rather than interchangeable, and that further research on the motivational systems underlying behavior in each of the two tests is needed. © 2012 Blaser, Rosemberg.

Dietrich M.O.,Yale University | Dietrich M.O.,Federal University of Rio Grande do Sul | Horvath T.L.,Yale University
Cell | Year: 2011

The drive to eat is controlled by neuronal circuits in the hypothalamus that respond to hormones signaling hunger or satiety. In this issue of Cell, Yang et al. (2011) reveal an AMPK-dependent synaptic pathway that sustains excitatory stimulation of the NPY/AgRP neurons that promote feeding behavior until satiety signals kick in. © 2011 Elsevier Inc.

Garcia-Santos D.,McGill University | Schranzhofer M.,McGill University | Horvathova M.,Palacky University | Jaberi M.M.,McGill University | And 3 more authors.
Blood | Year: 2014

Heme is essential for the functionof all aerobic cells.However, it canbetoxicwhen it occurs in a non-protein-bound form; cells maintain a fine balance between heme synthesis and catabolism. The only physiological mechanism of heme degradation is by heme oxygenases (HOs). The heme-inducible isoform, HO-1, has been extensively studied in numerous nonerythroid cells, but virtually nothing is known about the expression and potential significance of HO-1 in developing red blood cells. We have demonstrated that HO-1 is present in erythroid cells and that its expression is upregulated during erythroid differentiation. Overexpression of HO-1 in erythroid cells impairs hemoglobin synthesis, whereas HO-1 absence enhances hemoglobinization in cultured erythroid cells. Based on these results, we conclude that HO-1 controls the regulatory heme pool at appropriate levels for any given stage of erythroid differentiation. In summary, our study brings to light the importance of HO-1 expression for erythroid development and expands our knowledge about the fine regulation of hemoglobin synthesis in erythroid cells.Our results indicate that HO-1 plays an important role as a coregulator of the erythroid differentiation process. Moreover, HO-1 expression must be tightly regulated during red blood cell development. © 2014 by The American Society of Hematology.

Figueiro P.S.,Federal University of Rio Grande do Sul | Raufflet E.,HEC Montreal
Journal of Cleaner Production | Year: 2015

Sustainability has received increasing attention in management education over the past ten years. This article reviews a decade's worth of research in a systematic analysis of 63 articles published in international higher education and management education journals between 2003 and 2013. The purpose of this article is to map and review the publications based on the analysis according to the following four categories: (1) Types of papers, (2) Challenges, (3) Teaching techniques, and (4) Curriculum orientation. The scientific value of this article focuses on three main contributions to management education. First, while most articles are descriptive, focusing on specific, unique experiences in a given institution or with a particular teaching method or tool, few situate themselves within the broader philosophy and design of management education. The second contribution is an evaluation of the status of sustainability in management education as a field of study. This systematic review highlights the lack of consistency in the concepts used: no stable categories emerge from these articles and very few studies integrate the three levels of educational philosophy - teaching, program design, and learning. Third, this review highlights future directions for sustainability in management education institution-wide. While all articles highlight the need for curriculum change, very few specify how this change could and would be achieved by course design or explicit educational paradigms. © 2014 Elsevier Ltd. All rights reserved.

Falcula hyalina Takano (1983: 24) is an epizoic diatom commonly associated with coastal copepods in many parts of the world (Takano 1983, Mahoney & Gibson 1983, Hiromi et al. 1985, Prasad et al. 1989, Souza-Mosimann et al. 1989, Fernandes & Calixto-Feres 2012, Li et al. 2014). The species was described and illustrated using the transmission electron microscope by Takano (1983) who differentiated it from other taxa of the genus—F. rogallii Voigt (1960: 86), F. media Voigt (1960: 87), F. semiundulata Voigt (1960: 87), F. paracelsiana Voigt (1961: 54) and F. media var. subsalina Proshkina-Lavrenko (1963: 36)—by the morphometric features of the valve (length, width, and stria and areolae density). Some years later, Prasad et al. (1989) improved the morphological features of F. hyalina using the scanning electron microscope and discussed the relation of the species with similar taxa. Round et al. (1990), in the diacritic description of the genus, raised the question that F. hyalina had some features that could not match with Falcula, such as the wider sternum and poroidal apical pore field (ocellulimbus), as opposed to a series of slits at the apices. Therefore, the taxonomic position of F. hyalina still remains uncertain. © 2016 Magnolia Press.

Lorenzini G.,University of Parma | Garcia F.L.,Grande Rio University | Dos Santos E.D.,Grande Rio University | Biserni C.,University of Bologna | Rocha L.A.O.,Federal University of Rio Grande do Sul
International Journal of Heat and Mass Transfer | Year: 2012

In this paper we consider the geometrical optimization of a complex cavity, namely a T-Y-shaped cavity with two additional lateral intrusions into a solid conducting wall. The assemblies of cavities were cooled by a steady convective stream while the solid generates heat uniformly and it is insulated on the external perimeter. Two sets of geometrical configurations, having different displacement of the lateral cavities, named "Design 1" and "Design 2", have been numerically investigated. The objective is to minimize the global thermal resistance between the solid and the complex assembly of cavities. The basic idea is to give the assembly more freedom to morph by increasing its degrees of freedom: it is expected, according to the constructal design, that an increase of the geometrical complexity will lead to an augmentation of the thermal performance. The analysis demonstrated that not all degrees of freedom play the same role in the performance of the complex cavity design: an improvement of approximately 45% has been observed after the optimization of the ratio H 3/L 3 while the optimization of the parameters H 1/L 1 and H 2/L 2 led to an additional gain of only 1%. Design 2's performance proofed to be superior to Design 1's performance, because its lateral cavities are able to penetrate more efficiently into the solid body. Furthermore, Design 2's maximal excess temperature is approximately half of the corresponding dimensionless maximal excess temperature of the basic T-Y assembly, i.e., a cavity shaped as T and Y without lateral intrusions. © 2011 Elsevier Ltd. All rights reserved.

Pampanelli A.B.,GKN Driveline Americas | Found P.,University of Cardiff | Bernardes A.M.,Federal University of Rio Grande do Sul
Journal of Cleaner Production | Year: 2014

The purpose of lean thinking is to promote continuous improvement culture within a business. Specifically, lean thinking describes a work philosophy already used by many manufacturers. Lean thinking considers the expenditure of resources, for any goal other than the creation of value for the end customer to be wasteful. There has been much anecdotal evidence suggesting that a lean approach can help make the case for environmental impact reduction to businesses. We present an integrated lean and green approach that results in (i) a reduction in production waste and (ii) a reduction in environmental impact. Evidence-based results are first reviewed here. We show that previous findings identify a specific level of lean and manufacturing stability as a prerequisite for integrating lean and green at the manufacturing cell level. The main objective of this paper is to propose a new model, which we call the Lean & Green Model. In this model, we integrate environmental sustainability into pure lean thinking. The model presented in this paper adopts a Kaizen approach to improve mass and energy flows in manufacturing environments that already possess the necessary deployment level to apply lean thinking. The model was designed for, and is limited to, the cell level, which is the first stream level of a manufacturing business that supports the principles of lean thinking. The paper then presents findings from an application of the model in a major international engineering corporation, including the results of model deployment at the cell level. Such findings confirm that the Lean & Green Model can reduce resource use from 30 to 50% on average and has the potential to reduce the total cost of mass and energy flows in a cell by 5-10%. © 2013 Elsevier Ltd. All rights reserved.

Farina L.,Federal University of Rio Grande do Sul
Physics of Fluids | Year: 2010

The radiation of water waves by heaving horizontal disk at a shallow submergence depth is considered. The problem is formulated as a Fredholm integral equation. The resonant frequencies originating from the shallow submergence are examined and their locations are computed by a modified Newton's method. The hydrodynamic coefficients in a neighborhood of a resonance pole are found to be represented by circles in the complex plane. An asymptotic approximation is obtained for small values of the submergence depth. The relationship between the small-submergence first order problem and the dock problem is explored and found to be clearly represented by the added mass and damping coefficients. © 2010 American Institute of Physics.

Ferreira L.,Federal University of Rio Grande do Norte | Borenstein D.,Federal University of Rio Grande do Sul
Expert Systems with Applications | Year: 2012

The selection supplier problem has received a lot of attention from academics in recent years. Several models were developed in the literature, combining consolidated operations research and artificial intelligence methods and techniques. However, the tools presented in the literature neglected learning and adaptation, since this decision making process is approached as a static one rather than a highly dynamic process. Delays, lack of capacity, quality related issues are common examples of dynamic aspects that have a direct impact on long-term relationships with suppliers. This paper presents a novel method based on the integration of influence diagram and fuzzy logic to rank and evaluate suppliers. The model was developed to support managers in exploring the strengths and weaknesses of each alternative, to assist the setting of priorities between conflicting criteria, to study the sensitivity of the behavior of alternatives to changes in underlying decision situations, and finally to identify a preferred course of action. To be effective, the computational implementation of the method was embedded into an information system that includes several functionalities such as supply chain simulation and supplier's databases. A case study in the biodiesel supply chain illustrates the effectiveness of the developed method. © 2012 Elsevier Ltd. All rights reserved.

Streit R.E.,Catholic University of Brasilia | Borenstein D.,Federal University of Rio Grande do Sul
Expert Systems with Applications | Year: 2012

The financial system, which has been investigated by various researchers, is a rather complicated environment. Most research has only been concerned with quantitative factors (technical indexes), though qualitative factors (e.g.; political situation, social conditions, international events, government policies, among others) play a critical role in the financial system environment, determining the regulatory policies within an economy. This paper presents a fuzzy knowledge-based model to measure the qualitative aspects related to one of the most important financial instruments used to regulate an economy, the base interest rate. The development and assessment of the proposed model was based on the Brazilian economy. Evaluation of the results obtained indicates that our approach gives good results when compared with real data and statistical-based forecasting tools. The main advantage of our approach is its capability to forecast long term interest rate expectations when combined with a powerful econometric model. © 2011 Elsevier Ltd. All rights reserved.

Miguel L.F.F.,Federal University of Rio Grande do Sul | Fadel Miguel L.F.,Federal University of Santa Catarina
Expert Systems with Applications | Year: 2012

Mass optimization on shape and sizing with multiple natural frequency constraints are highly nonlinear dynamic optimization problems. Multiple natural frequency constraints normally cause difficult dynamic sensitivity analysis and, in addition, two different types of design variables, nodal coordinates and cross-sectional areas, often lead to divergence. Thus, the choice of the appropriated method to solve this kind of problem is of paramount importance. Within this context, in this paper two of the most recent metaheuristic algorithms developed in the last decade, Harmony Search (HS) and Firefly Algorithm (FA), are used, for the first time here, to solve truss shape and sizing optimization with multiple natural frequency constraints. Since these metaheuristic algorithms are not a gradient-based search, they avoid most of the pitfalls of any gradient-based search algorithms. The effectiveness of Harmony Search and Firefly Algorithm is demonstrated through four benchmark structural optimization problems for solving shape and sizing optimization of trusses with multiple frequency constraints. The results showed that both metaheuristic algorithms reached, in a relatively low computational time, better results than the literature in three of the four examples considered, and in the other example the structure is approximately equal to the best one found, emphasizing the excellent capacity of both methods. © 2012 Elsevier Ltd. All rights reserved.

Simeoni Jr. W.,Federal University of Rio Grande do Sul
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2010

The purpose of this Letter is to conjecture a characterization of the anisotropic equipartition state. The anisotropic equipartition state is defined through a phase space density which is uniform on the invariant surface of ξ, where ξ is the ratio between the oscillation energies in the x- and y-directions. It is a version of the ergodic hypothesis where the invariant surface of ξ plays the role of the conserved energy. We show that the anisotropic equipartition state is characterized by the following properties: the development of an elliptical shape with increasing size along the x-direction, the presence of a coupling between transversal emittances, halo formation along a preferential direction, stationarity of the temperature and a growth of the entropy in the cascade form. © 2010 Elsevier B.V. All rights reserved.

Weniger P.,RWTH Aachen | Kalkreuth W.,Federal University of Rio Grande do Sul | Busch A.,Royal Dutch Shell | Krooss B.M.,RWTH Aachen
International Journal of Coal Geology | Year: 2010

An experimental study has been conducted to assess the potential for coalbed methane production and carbon dioxide storage in coals, carbonaceous shales and source rocks in the Paraná Basin in Brazil. High-pressure sorption tests with methane and carbon dioxide were performed on coal and carbonaceous shales from the Santa Terezinha Coalfield and samples from two principal petroleum source rocks. Measured excess sorption capacities ranged from 0.03 to 0.47mmol/g for methane and 0.14 to 0.81mmol/g for carbon dioxide, showing a decrease with decreasing organic matter content. Linear regression lines for methane sorption capacity vs. TOC extrapolated to approximately zero, whereas for carbon dioxide the intercept of the regression line indicated a residual sorption capacity of ~0.2mmol/g on the mineral matter. Present-day gas contents of coals collected from the first CBM well in the Santa Terezinha Coalfield correspond to 13-38% of the measured maximum sorption capacities. Carbon dioxide sorption capacities exceed methane sorption capacities by a factor of 1.9 to 6.9 for these coals. Free sorption capacities of the under-saturated coals in combination with preferential sorption of carbon dioxide could favour CO2-enhanced methane recovery and CO2 storage in coals and shales of the study area. Based upon the calculated coal reserves, gas contents and measured sorption capacities, a total storage potential of 15.4Gt CO2 was estimated for an area of 20×40km2 in the Santa Terezinha coal field, assuming a combined CO2 enhanced coalbed methane (ECBM) production and CO2 storage operation. To fully evaluate the potential for carbon dioxide storage and coalbed methane production, further studies are required to assess producibility of methane and efficiency of long-term CO2 storage in the study area. © 2010 Elsevier B.V.

Dennis L.A.,University of Liverpool | Fisher M.,University of Liverpool | Webster M.P.,Daresbury Laboratory | Bordini R.H.,Federal University of Rio Grande do Sul
Automated Software Engineering | Year: 2012

In this paper we describe a verification system for multi-agent programs. This is the first comprehensive approach to the verification of programs developed using programming languages based on the BDI (belief-desire-intention) model of agency. In particular, we have developed a specific layer of abstraction, sitting between the underlying verification system and the agent programming language, that maps the semantics of agent programs into the relevant model-checking framework. Crucially, this abstraction layer is both flexible and extensible; not only can a variety of different agent programming languages be implemented and verified, but even heterogeneous multi-agent programs can be captured semantically. In addition to describing this layer, and the semantic mapping inherent within it, we describe how the underlying model-checker is driven and how agent properties are checked. We also present several examples showing how the system can be used. As this is the first system of its kind, it is relatively slow, so we also indicate further work that needs to be tackled to improve performance. © 2011 Springer Science+Business Media, LLC.

Conceicao P.C.,Federal Technological University of Parana | Dieckow J.,Federal University of Parana | Bayer C.,Federal University of Rio Grande do Sul
Soil and Tillage Research | Year: 2013

Increases in carbon (C) input and stabilization are key processes to turn soils into sinks of atmospheric CO2-C and help mitigating global warming. We hypothesized (i) that C sequestration in no-tillage soil is further enhanced by high input cropping systems and (ii) that the sequestered C is stored mainly in the mineral associated fraction. The objective of this study was to assess, in 2003, the C sequestration and stabilization in a subtropical Acrisol (Eldorado do Sul, Brazil) subjected to 18-year conventional tillage [CT] and no-tillage [NT] combined with two cropping systems: black oat (Avena strigosa Schreb) as winter cover crop - maize (Zea mays L.) as summer grain crop [Ot/M]; and black oat plus vetch (Vicia villosa Roth) as winter cover crops - maize in summer intercropped with cowpea (Vigna unguiculata (L.) Walp) cover crop [Ot+V/M+C]. Soil C stock in the 0-20cm layer was higher in NT than in CT, either in Ot/M (31.1 vs. 27.8Mgha-1, P<0.05) or Ot+V/M+C (37.3 vs. 32.8Mgha-1, P<0.05). Annual C sequestration rate in NT relative to CT was 0.25Mgha-1 in Ot+V/M+C and 0.18Mgha-1 in Ot/M, in agreement to the higher biomass-C addition and legume cover crops inclusion in Ot+V/M+C (7.6 vs 4.0Mgha-1 year-1) and to our first hypothesis. Increase in the proportion of large macroaggregates (9.51-4.76mm) and of mean weight diameter occurred in NT soil up to 10cm depth, both in Ot/M and Ot+V/M+C. In NT, most of the C accumulation relative to CT occurred in the mineral-associated fraction, showing the importance of organo-mineral interaction in C stabilization and supporting our second hypothesis. However, the physical protection by aggregates played equally important role by stabilizing the occluded particulate organic matter (occluded-POM) before it was further stabilized by organo-mineral interaction. No-tillage is recommended as a sustainable soil management, but to increase soil C accumulation, the potential of cropping systems such those based on legume cover crops must be concurrently explored. © 2013 Elsevier B.V.

Clarke R.T.,Federal University of Rio Grande do Sul
Water Resources Research | Year: 2013

A comparison of six procedures for estimating the linear trend parameter β in annual maximum 1 day river flows at five sites in southern Brazil showed marked differences between, on the one hand, estimates obtained by incorporating trend into the generalized extreme value (GEV) location parameter with all parameters estimated by maximum likelihood (ML) and on the other hand, estimates found by least squares, trend removal prior to fitting the GEV by ML, boot-strap sampling, and Theil-Sen estimation. ML estimates of trend were considerably smaller than those given by all other procedures. The same was true where trend had been incorporated into the Gumbel location parameter. Where 95% confidence intervals were calculated for the "true" trend β by different procedures, some confidence intervals bracketed zero (indicating that the trend was not "significant" at the 5% level), but there was no consistency between results from different procedures; Theil-Sen confidence intervals always bracketed zero, confidence intervals given by detrending never did. It is concluded that not only do different estimation procedures give different measures of trend uncertainty, as reported elsewhere, but the estimated trends themselves may differ, and the paper suggests an explanation why this may occur. Some philosophical issues relating to estimation of trend in climatological and hydrological extremes are discussed, and it is concluded that selection of a method to estimate trend must depend on context. Key Points Trends in extremes differ according to how you calculate them. The uncertainties in estimated trends also differ. Hence there is uncertainty in trend magnitude. ©2013. American Geophysical Union. All Rights Reserved.

Brandelli A.,Federal University of Rio Grande do Sul
Mini-Reviews in Medicinal Chemistry | Year: 2012

Antimicrobial peptides have been extensively investigated for their potential applications as therapeutics and food biopreservatives. The antimicrobial activity may be impaired by the susceptibility for proteolytic degradation and undesirable interactions of the antimicrobial peptide in the biological environment. Development of nanostructures for entrapment and delivery of antimicrobial peptides may represent an alternative to the direct application of these substances. Lipid nanovesicles have been developed for encapsulation of antimicrobial peptides. Phosphatidylcholine is often employed in liposome manufacture, which is mostly achieved by the thin-film hydration method. Nanofibers may allow different physical modes of drug loading, including direct adsorption on the nanofiber surface or the assembly of drug-loaded nanoparticles. Self-assembled peptides reveal attractive features as nanostructures for applications in drug delivery and promising as antimicrobial agent for treatment of brain infections. Magnetic nanoparticles and nanotubules are also potential structures for entrapment of antimicrobial peptides. Nanoparticles can be also chemically modified with specific cell surface ligands to enhance cell adhesion and site specific delivery. This article reviews the most important nanostructures as promising tools for peptide delivery systems. © 2012 Bentham Science Publishers.

Dietrich M.O.,Yale University | Dietrich M.O.,Federal University of Rio Grande do Sul | Liu Z.-W.,Yale University | Horvath T.L.,Yale University
Cell | Year: 2013

Summary Mitochondria are key organelles in the maintenance of cellular energy metabolism and integrity. Here, we show that mitochondria number decrease but their size increase in orexigenic agouti-related protein (Agrp) neurons during the transition from fasted to fed to overfed state. These fusion-like dynamic changes were cell-type specific, as they occurred in the opposite direction in anorexigenic pro-opiomelanocortin (POMC) neurons. Interfering with mitochondrial fusion mechanisms in Agrp neurons by cell-selectively knocking down mitofusin 1 (Mfn1) or mitofusin 2 (Mfn2) resulted in altered mitochondria size and density in these cells. Deficiency in mitofusins impaired the electric activity of Agrp neurons during high-fat diet (HFD), an event reversed by cell-selective administration of ATP. Agrp-specific Mfn1 or Mfn2 knockout mice gained less weight when fed a HFD due to decreased fat mass. Overall, our data unmask an important role for mitochondrial dynamics governed by Mfn1 and Mfn2 in Agrp neurons in central regulation of whole-body energy metabolism. © 2013 Elsevier Inc.

de Almeida L.,Cornell University | Idiart M.,Federal University of Rio Grande do Sul | Linster C.,Cornell University
Journal of Neurophysiology | Year: 2013

In this work we investigate in a computational model how cholinergic inputs to the olfactory bulb (OB) and piriform cortex (PC) modulate odor representations. We use experimental data derived from different physiological studies of ACh modulation of the bulbar and cortical circuitry and the interaction between these two areas. The results presented here indicate that cholinergic modulation in the OB significantly increases contrast and synchronization in mitral cell output. Each of these effects is derived from distinct neuronal interactions, with different groups of interneurons playing different roles. Both bulbar modulation effects contribute to more stable learned representations in PC, with pyramidal networks trained with cholinergicmodulated inputs from the bulb exhibiting more robust learning than those trained with unmodulated bulbar inputs. This increased robustness is evidenced as better recovery of memories from corrupted patterns and lower-concentration inputs as well as increased memory capacity. © 2013 the American Physiological Society.

Caetano N.R.,Federal University of Rio Grande do Sul | Figueira da Silva L.F.,Pontifical Catholic University of Rio de Janeiro
Experimental Thermal and Fluid Science | Year: 2015

Turbulent non-premixed flames of natural gas and air stabilized in a semi-infinite bluff-body burner are assessed in this work. Different situations are investigated corresponding either to jet or to wake-dominated flow fields. Measurements of the OH radical fluorescence and of the velocity field are obtained by joint Planar Laser Induced Fluorescence (PLIF) and Particle Image Velocimetry (PIV) techniques. First, a study of two chemically inert cases is presented to base the flow field structure. Then, the instantaneous OH fluorescence and velocity fields analysis underscore the local extinctions and the interactions between combustion and turbulence. A comparison between the Reynolds stresses distribution reveals that the flame presence generates turbulence in intermittently lifted situations and suppresses part of the Reynolds stresses when fully lifted. © 2015.

Doering D.,Federal University of Rio Grande do Sul
Proceedings - 2014 12th IEEE International Conference on Industrial Informatics, INDIN 2014 | Year: 2014

The evolution of recent embedded systems has made their design very complex since the number of functionalities implemented in them is large and the platforms that are used to run these applications may include several heterogeneous and high-performance processing units. Model Driven Engineering has been advocated as a possible solution to help the system designers to deal with these highly complex systems developments. This paper presents the HIPAO2 methodology. The proposed methodology uses the Model Driven Engineering concepts to go from requirement to Platform Independent Model and Platform Models using object and aspect oriented modeling. It also includes a Model-Driven Design Space exploration framework to perform hardware/software partitioning and generate Platform Specific Models. Code is generated using model-to-text transformations. HIPAO2 focuses on the development of systems of system and provides mechanisms for reuse of previously developed subsys-tems. The methodology is applied to the development of an image processing system deployed in an Unmanned Autonomous Vehicle. © 2014 IEEE.

Schiwietz G.,Helmholtz Center Berlin | Grande P.L.,Federal University of Rio Grande do Sul
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2012

Recent theoretical developments in the unitary convolution approximation (UCA) for electronic energy losses of bare and screened ions are presented. Examples are given for proton beams and rare-gas targets. For gas targets there exists a sufficient amount of experimental data on charge exchange, for pinpointing the largely unknown stopping-power contribution of electron-capture processes at low and intermediate energies. © 2011 Elsevier B.V. All rights reserved.

Zhang Z.,University of Michigan | Filho M.S.,Federal University of Rio Grande do Sul | Nor J.E.,University of Michigan
Oral Oncology | Year: 2012

Emerging evidence indicates that a small population of cancer cells is highly tumorigenic, endowed with self-renewal, and has the ability to differentiate into cells that constitute the bulk of tumors. These cells are considered the "drivers" of the tumorigenic process in some tumor types, and have been named cancer stem cells. Epithelial-mesenchymal transition (EMT) appears to be involved in the process leading to the acquisition of stemness by epithelial tumor cells. Through this process, cells acquire an invasive phenotype that may contribute to tumor recurrence and metastasis. Cancer stem cells have been identified in human head and neck squamous cell carcinomas (HNSCC) using markers such as CD133 and CD44 expression, and aldehyde dehydrogenase (ALDH) activity. The head and neck cancer stem cells reside primarily in perivascular niches in the invasive front where endothelial-cell initiated events contribute to their survival and function. In this review, we discuss the state-of-the-knowledge on the pathobiology of cancer stem cells, with a focus on the impact of these cells to head and neck tumor progression. © 2011 Elsevier Ltd. All rights reserved.

Hoss M.,Federal University of Santa Maria | Ten Caten C.S.,Federal University of Rio Grande do Sul
International Journal of Production Research | Year: 2013

Academia has produced theoretical and practical knowledge about lean for over 30 years, and for that reason, research is in a mature phase. To organise this knowledge, we propose a typology of lean schools of thought. Schools were categorised into two paradigms of organisational analysis - interpretivist and functionalist - to clarify theoretical assumptions about how each conducts scientific investigations and what contributions they generate. Seven schools were identified: systems engineering, systems architecture, operations research, organisational development, contingency systems, socio-technical systems and evolutionary. Persistent practical problems should guide production and operations management research such as the difficulties companies face with adoption and sustainability of lean practices. The typology proposed in this study provides a theoretical framework and a respective school for these problematical situations. The evolutionary school in the interpretivist paradigm seems to be more appropriate; action research as a methodology should be used since it is consistent with interpretivism assumptions. The originality of this paper lies within a proposal of lean schools of thought not found in the literature. Directions for research that have more meaning for companies seeking lean transformation are proposed. © 2013 Copyright Taylor and Francis Group, LLC.

Ribeiro B.M.G.,Federal University of Rio Grande do Sul
2015 Joint Urban Remote Sensing Event, JURSE 2015 | Year: 2015

Recent developments in geotechnologies provide resources to propose innovative strategies for urban and environmental management, including remote sensing data and computational resources for processing them. With the main objective of identifying urban areas of illegal occupation, this work uses WorldView-2-sensor images and the InterIMAGE, an image interpretation software, based on knowledge, under development by PUC-RJ in cooperation with INPE. Confirmed the potential of Geographic Object-Based Image Analysis (GEOBIA) and, on the other hand, the complexity on building the classification models, this work performs and evaluates land cover classification using C4.5 decision tree algorithm, which enables to quickly select the most representative attributes for each class and generate simple classification rules. The results show that data mining technique presented high classification performance. Using the land cover classes, we proceeded with the land use classification to identify areas of irregular occupation. The thematic maps achieved high values of overall accuracy and Kappa index. Typical classifications have been resolved by discriminating nine land cover classes. © 2015 IEEE.

Brizola E.,Federal University of Rio Grande do Sul | Staub A.L.P.,Physiatry and Rehabilitation Service | Felix T.M.,Medical Genetics Service
Pediatric Physical Therapy | Year: 2014

PURPOSE: To analyze clinical and functional features of children and adolescents with osteogenesis imperfecta (OI). METHODS: A cross-sectional study of 62 participants examined clinical, body structure and function and activity features. RESULTS: A total of 31 participants had OI type I, 9 had type III, and 22 had type IV. Mild (type I) and moderate/severe (types III and IV) OI differed significantly in occurrence of fractures, presence of bone deformities, the use of intramedullary rods, bone mineral density, and bisphosphonate therapy. Age of gait acquisition showed an association with overall joint range of motion and an inverse relationship with overall muscle strength. Level of ambulation was associated with overall muscle strength and inversely associated with overall joint range of motion. CONCLUSIONS: Features vary according to OI type. Moderate and severe forms of OI are associated with greater functional limitation, influenced by fracture history, which negatively affects the acquisition and level of ambulation. Copyright © 2014 Wolters Kluwer Health /Lippincott Williams & Wilkins and Section on Pediatrics of the American Physical Therapy.

Baer M.D.,Pacific Northwest National Laboratory | Stern A.C.,University of California at Irvine | Levin Y.,Federal University of Rio Grande do Sul | Tobias D.J.,University of California at Irvine | Mundy C.J.,Pacific Northwest National Laboratory
Journal of Physical Chemistry Letters | Year: 2012

We demonstrate that the driving forces for ion adsorption to the air-water interface for point charge models result from both cavitation and a term that is of the form of a negative electrochemical surface potential. We carefully characterize the role of the free energy due to the electrochemical surface potential computed from simple empirical models and its role in ionic adsorption within the context of dielectric continuum theory. Our research suggests that the electrochemical surface potential due to point charge models provides anions with a significant driving force for adsoprtion to the air-water interface. This is contrary to the results of ab initio simulations that indicate that the average electrostatic surface potential should favor the desorption of anions at the air-water interface. The results have profound implications for the studies of ionic distributions in the vicinity of hydrophobic surfaces and proteins. © 2012 American Chemical Society.

Marin S.M.,Santa Catarina State University | Witt R.R.,Federal University of Rio Grande do Sul
Prehospital and Disaster Medicine | Year: 2015

Introduction Hospital nurses play a key role in the aftermath of the occurrence of disasters and need specific competencies to work in these situations. From a global perspective, few models exist that focus on disaster nursing. Problem This study aimed to identify hospital nurses' competencies in disaster situations. Method A qualitative, descriptive, exploratory study was developed using focus groups as a method of data collection. Three meetings were held from June through September 2012 with nurses who worked at a hospital used as reference for disaster situations in the South of Brazil. Thematic analysis of collected data generated the competencies. For statement standardization, a format consistent with a verb, a noun, and a complement was adopted. Results The group validated 17 competencies, which were organized according to the phases of emergency management described by the World Health Organization (WHO) and classified in domain areas of management, health care, communication, and education. Conclusions The competencies identified in this study can contribute to the education and practice of nurses in the hospital ambience, strengthening its capacity to face disaster situations. Marin SM, Witt RR. © World Association for Disaster and Emergency Medicine 2015.

Dotto G.L.,Grande Rio University | Lima E.C.,Federal University of Rio Grande do Sul | Pinto L.A.A.,Grande Rio University
Bioresource Technology | Year: 2012

The biosorption of food dyes FD&C red no. 40 and acid blue 9 onto Spirulina platensis nanoparticles was studied at different conditions of pH and temperature. Four isotherm models were used to evaluate the biosorption equilibrium and the thermodynamic parameters were estimated. Infra red analysis (FT-IR) and energy dispersive X-ray spectroscopy (EDS) were used to verify the biosorption behavior. The maximum biosorption capacities of FD&C red no. 40 and acid blue 9 were found at pH4 and 298K, and the values were 468.7mgg -1 and 1619.4mgg -1, respectively. The Sips model was more adequate to fit the equilibrium experimental data (R 2>0.99 and ARE<5%). Thermodynamic study showed that the biosorption was exothermic, spontaneous and favorable. FT-IR and EDS analysis suggested that at pH4 and 298K, the biosorption of both dyes onto nanoparticles occurred by chemisorption. © 2011 Elsevier Ltd.

Santos J.L.,Federal University of Rio Grande do Sul | Choquette M.,Cincinnati Childrens Hospital Medical Center | Bezerra J.A.,Cincinnati Childrens Hospital Medical Center
Current Gastroenterology Reports | Year: 2010

Inherited syndromes of intrahepatic cholestasis and biliary atresia are the most common causes of chronic liver disease and the prime indication for liver transplantation in children. Our understanding of the pathogenesis of these diseases has increased substantially by the discovery of genetic mutations in children with intrahepatic cholestasis and the findings that inflammatory circuits are operative at the time of diagnosis of biliary atresia. Building on this solid foundation, recent studies provide new insight into genotype-phenotype relationships and how mutations produce altered bile composition and cholestasis. New evidence exists that although liver transplantation is curative for patients with end-stage liver disease owing to cholestasis, some patients may develop recurrence of cholestasis because of the emergence of autoantibodies that disrupt canalicular function in the new graft. Progress is also evident in biliary atresia, with recent studies identifying candidate modifier genes and directly implicating lymphocytes and inflammatory signals in the pathogenesis of bile duct injury and obstruction. © 2010 Springer Science+Business Media, LLC.

Henkes S.,Syracuse University | Brito C.,Federal University of Rio Grande do Sul | Dauchot O.,CNRS Gulliver Laboratory
Soft Matter | Year: 2012

The study of the jamming transition of granular and colloidal systems, has lead to a proliferation of theoretical and numerical results formulated in the language of the eigenspectrum of the dynamical matrix for these disordered systems. Only recently however, have these modes been accessed experimentally in colloidal and granular media, by computing the eigenmodes of the covariance matrix of the particle positions. At the same time, new conceptual and methodological questions regarding the interpretation of these results have appeared. In the present paper, we first give an overview of the theoretical framework which is appropriate to interpret the eigenmodes and eigenvalues of the correlation matrix in terms of the vibrational properties of these systems. We then illustrate several aspects of the statistical and data analysis techniques necessary to extract reliable results from experimental data. Concentrating on the cases of hard sphere simulations, colloidal and granular experiments, we discuss how to test, in turn, for the existence of a metastable state and the statistical independence of the sampling, the effect of experimental resolution, and the harmonic hypothesis underlying the approach; highlighting both the promises and limitations of this approach. © 2012 The Royal Society of Chemistry.

Dietrich M.O.,Yale University | Dietrich M.O.,Federal University of Rio Grande do Sul | Horvath T.L.,Yale University
Trends in Neurosciences | Year: 2013

The past 20 years witnessed an enormous leap in understanding of the central regulation of whole-body energy metabolism. Genetic tools have enabled identification of the region-specific expression of peripheral metabolic hormone receptors and have identified neuronal circuits that mediate the action of these hormones on behavior and peripheral tissue functions. One of the surprising findings of recent years is the observation that brain circuits involved in metabolism regulation remain plastic through adulthood. In this review, we discuss these findings and focus on the role of neurons and glial cells in the dynamic process of plasticity, which is fundamental to the regulation of physiological and pathological metabolic events. © 2013 Elsevier Ltd.

Stein R.,Federal University of Rio Grande do Sul | Malhotra A.,St Georges, University of London
Journal of Electrocardiology | Year: 2015

Athletic intensive exercise is associated with repolarization changes affecting the ST-segment and T-wave morphology. The prevalence and distribution of these alterations are influenced by several demographic factors. One of the most challenging conundrums for both the cardiologist and the sports medicine physician is the correct interpretation of these repolarization changes to prevent an erroneous diagnosis with potentially serious consequences. A 12-lead electrocardiogram (ECG) demonstrating inverted T-waves may represent the first and only sign of such inherited heart muscle diseases, and may precede the detection of any structural changes in the heart, however, T-wave inversion in leads V1-V4 in black athletes may represent ethnic variation which is exaggerated by exercise. © 2015 Elsevier Inc. All rights reserved.

Bueno L.,Federal University of Santa Catarina | Dias A.S.,Federal University of Rio Grande do Sul | Steele J.,University College London
Quaternary International | Year: 2013

Between 13,000 and 8000 14C BP, eastern South America was settled by a stable and diversified population of hunter-gatherers. Archaeological excavation in the past twenty years has yielded increasingly consistent evidence of occupation in different regions of Brazil since the end of the Pleistocene, with dates at least contemporary to the Clovis Horizon in North America. This is addressed by documenting and analysing the quantity, quality and distribution of archaeological 14C dates from Brazil during this period. A total of 277 dates from 90 sites are tabulated, mapped, and included in the analysis. During the Late Pleistocene there was a pioneer phase of human colonization, with dispersal inland through the major river systems. Subsequently, the Early Holocene saw the first phase of established settlement of Brazil's interior. There seems to be an archaeological threshold reached at ca. 10,500 years 14C BP: numbers of sites increase, there is evidence of settlement of all major biomes, and there is clear evidence of inter-regional cultural diversity. © 2013 Elsevier Ltd and INQUA.

Goncalves M.S.,Federal University of Santa Maria | Silveira A.F.,Federal University of Santa Maria | Teixeira A.R.,Federal University of Rio Grande do Sul | Hyppolito M.A.,University of Sao Paulo
Journal of Laryngology and Otology | Year: 2013

Introduction: Cisplatin is an effective chemotherapeutic agent commonly used in the treatment of malignant tumours, but ototoxicity is a significant side effect. Objectives: To discuss the mechanisms of cisplatin ototoxicity and subsequent cell death, and to present the results of experimental studies. Material and methods: We conducted a systematic search for data published in national and international journals and books, using the Medline, SciELO, Bireme, LILACS and PubMed databases. Results: The nicotinamide adenine dinucleotide phosphate oxidase 3 isoform (also termed NOX3) seems to be the main source of reactive oxygen species in the cochlea. These reactive oxygen species react with other molecules and trigger processes such as lipid peroxidation of the plasma membrane and increases in expression of the transient vanilloid receptor potential 1 ion channel. Conclusion: Cisplatin ototoxicity proceeds via the formation of reactive oxygen species in cochlear tissue, with apoptotic cell death as a consequence. Copyright © JLO (1984) Limited 2013Â.

Bazzan A.L.C.,Federal University of Rio Grande do Sul | Klugl F.,Orebro University
Synthesis Lectures on Artificial Intelligence and Machine Learning | Year: 2013

Urban mobility is not only one of the pillars of modern economic systems, but also a key issue in the quest for equality of opportunity, once it can improve access to other services. Currently, however, there are a number of negative issues related to traffic, especially in mega-cities, such as economical issues (cost of opportunity caused by delays), environmental (externalities related to emissions of pollutants), and social (traffic accidents). Solutions to these issues are more and more closely tied to information and communication technology. Indeed, a search in the technical literature (using the keyword "urban traffic to filter out articles on data network traffic) retrieved the following number of articles (as of December 3, 2013): 9,443 (ACM Digital Library), 26,054 (Scopus), and 1,730,000 (Google Scholar). Moreover, articles listed in the ACM query relate to conferences as diverse as MobiCom, CHI, PADS, and AAMAS. This means that there is a big and diverse community of computer scientists and computer engineers who tackle research that is connected to the development of intelligent traffic and transportation systems. It is also possible to see that this community is growing, and that research projects are getting more and more interdisciplinary. To foster the cooperation among the involved communities, this book aims at giving a broad introduction into the basic but relevant concepts related to transportation systems, targeting researchers and practitioners from computer science and information technology. In addition, the second part of the book gives a panorama of some of the most exciting and newest technologies, originating in computer science and computer engineering, that are now being employed in projects related to car-to-car communication, interconnected vehicles, car navigation, platooning, crowd sensing and sensor networks, among others. This material will also be of interest to engineers and researchers from the traffic and transportation community. © 2013 by Morgan and Claypool.

Lorenzini G.,University of Parma | Biserni C.,University of Bologna | Rocha L.A.O.,Federal University of Rio Grande do Sul
International Journal of Heat and Mass Transfer | Year: 2014

This paper applies constructal design to study the geometry of a X-shaped isothermal cavity and a X-shaped high conductivity pathway that penetrate into a solid conducting wall. The objective is to minimize the maximal excess of temperature of the whole system, i.e. the hot spots, independent of where they are located. There is uniform heat generation on the solid body, which is insulated on the external perimeter. The total volume and the cavity volume, as well as the high conductivity material volume, are fixed, but the geometric lengths and thickness of both X-shaped configurations can vary. The emerged optimal configurations and performance are reported graphically and numerically. The results indicate that the increase of the complexity of the geometry can facilitate the access of heat currents and improve the thermal performance. The degree of freedom L1/L0 proved to be significant on the performance of the X-shaped isothermal cavity, e.g. the once optimized ratio (L1/L0)o increases approximately 10% as the area fraction increases from = 0.05 to 0.3. As for the X-shaped pathway case, it has been demonstrated that the dimensionless thermal conductivity of the path k̃p and the area fraction have a strong effect on the performance and configuration of the X-shaped blades: the twice minimized θmax,mm decreases approximately 70% as k̃p increases from 30 to 300 and it decreases approximately 84% as augments from 0.01 to 0.2. Furthermore, the X-shaped conductive pathways configuration increases its performance monotonically with the augmentation of the pathways thermal conductivity: in correspondence to the highest possible value of k̃p, the X-shaped conductive pathways present approximately the same heat removal capacity of the X-shaped cavities optimized in the first part of the paper. © 2014 Elsevier Ltd.

Goldani A.A.S.,Federal University of Rio Grande do Sul | Downs S.R.,University of California at San Francisco | Widjaja F.,University of California at San Francisco | Lawton B.,University of California at San Francisco | Hendren R.L.,University of California at San Francisco
Frontiers in Psychiatry | Year: 2014

Autism spectrum disorders (ASDs) are complex, heterogeneous disorders caused by an interaction between genetic vulnerability and environmental factors. In an effort to better target the underlying roots of ASD for diagnosis and treatment, efforts to identify reliable biomarkers in genetics, neuroimaging, gene expression, and measures of the body's metabolism are growing. For this article, we review the published studies of potential biomarkers in autism and conclude that while there is increasing promise of finding biomarkers that can help us target treatment, there are none with enough evidence to support routine clinical use unless medical illness is suspected. Promising biomarkers include those for mitochondrial function, oxidative stress, and immune function. Genetic clusters are also suggesting the potential for useful biomarkers. © 2014 Goldani, Downs, Widjaja, Lawton and Hendren.

Zimmer E.R.,University Institute of Mental Health | Zimmer E.R.,Federal University of Rio Grande do Sul | Leuzy A.,University Institute of Mental Health | Benedet A.L.,University Institute of Mental Health | And 3 more authors.
Journal of Neuroinflammation | Year: 2014

Alzheimer's disease (AD) has been reconceptualized as a dynamic pathophysiological process, where the accumulation of amyloid-beta (Aβ) is thought to trigger a cascade of neurodegenerative events resulting in cognitive impairment and, eventually, dementia. In addition to Aβ pathology, various lines of research have implicated neuroinflammation as an important participant in AD pathophysiology. Currently, neuroinflammation can be measured in vivo using positron emission tomography (PET) with ligands targeting diverse biological processes such as microglial activation, reactive astrocytes and phospholipase A2 activity. In terms of therapeutic strategies, despite a strong rationale and epidemiological studies suggesting that the use of non-steroidal anti-inflammatory drugs (NSAIDs) may reduce the prevalence of AD, clinical trials conducted to date have proven inconclusive. In this respect, it has been hypothesized that NSAIDs may only prove protective if administered early on in the disease course, prior to the accumulation of significant AD pathology. In order to test various hypotheses pertaining to the exact role of neuroinflammation in AD, studies in asymptomatic carriers of mutations deterministic for early-onset familial AD may prove of use. In this respect, PET ligands for neuroinflammation may act as surrogate markers of disease progression, allowing for the development of more integrative models of AD, as well as for the measuring of target engagement in the context of clinical trials using NSAIDs. In this review, we address the biological basis of neuroinflammatory changes in AD, underscore therapeutic strategies using anti-inflammatory compounds, and shed light on the possibility of tracking neuroinflammation in vivo using PET imaging ligands. © 2014 Zimmer et al.; licensee BioMed Central Ltd.

Coupe B.,Saban Research Institute | Ishii Y.,Saban Research Institute | Dietrich M.O.,Yale University | Dietrich M.O.,Federal University of Rio Grande do Sul | And 6 more authors.
Cell Metabolism | Year: 2012

The hypothalamic melanocortin system, which includes neurons that produce pro-opiomelanocortin (POMC)-derived peptides, is a major negative regulator of energy balance. POMC neurons begin to acquire their unique properties during neonatal life. The formation of functional neural systems requires massive cytoplasmic remodeling that may involve autophagy, an important intracellular mechanism for the degradation of damaged proteins and organelles. Here we investigated the functional and structural effects of the deletion of an essential autophagy gene, Atg7, in POMC neurons. Lack of Atg7 in POMC neurons caused higher postweaning body weight, increased adiposity, and glucose intolerance. These metabolic impairments were associated with an age-dependent accumulation of ubiquitin/p62-positive aggregates in the hypothalamus and a disruption in the maturation of POMC-containing axonal projections. Together, these data provide direct genetic evidence that Atg7 in POMC neurons is required for normal metabolic regulation and neural development, and they implicate hypothalamic autophagy deficiency in the pathogenesis of obesity. © 2012 Elsevier Inc.

Fernandes L.A.F.,Federal University of Fluminense | Oliveira M.M.,Federal University of Rio Grande do Sul
Pattern Recognition | Year: 2012

The analysis of large volumes of unordered multidimensional data is a problem confronted by scientists and data analysts every day. Often, it involves searching for data alignments that emerge as well-defined structures or geometric patterns in datasets. For example, straight lines, circles, and ellipses represent meaningful structures in data collected from electron backscatter diffraction, particle accelerators, and clonogenic assays. Also, customers with similar behavior describe linear correlations in e-commerce databases. We describe a general approach for detecting data alignments in large unordered noisy multidimensional datasets. In contrast to classical techniques such as the Hough transforms, which are designed for detecting a specific type of alignment on a given type of input, our approach is independent of the geometric properties of the alignments to be detected, as well as independent of the type of input data. Thus, it allows concurrent detection of multiple kinds of data alignments, in datasets containing multiple types of data. Given its general nature, optimizations developed for our technique immediately benefit all its applications, regardless the type of input data. © 2012 Elsevier Ltd. All rights reserved.

Koster A.,Federal University of Rio Grande do Sul
Argument and Computation | Year: 2014

This survey is the first to review the combination of computational trust and argumentation. The combination of the two approaches seems like a natural match, with the two areas tackling different aspects of reasoning in an uncertain, social environment. We discuss the different areas of research and describe the approaches taken so far, analysing both how they address the problems and the challenges that are unaddressed. © 2014 Taylor & Francis.

Oliveira M.M.,Federal University of Rio Grande do Sul
Computing in Science and Engineering | Year: 2013

Various techniques can be used to improve visualization experiences for individuals with color vision deficiency, including recoloring, pattern superposition, and the use of a color-perception simulation model for assisting visualization designers. © 1999-2011 IEEE.

Garcia T.,Ecole Normale Superieure de Paris | Garcia T.,University Pierre and Marie Curie | Brunnet L.G.,Federal University of Rio Grande do Sul | De Monte S.,French Institute of Health and Medical Research
PLoS Computational Biology | Year: 2014

The evolutionary stability of cooperative traits, that are beneficial to other individuals but costly to their carrier, is considered possible only through the establishment of a sufficient degree of assortment between cooperators. Chimeric microbial populations, characterized by simple interactions between unrelated individuals, restrain the applicability of standard mechanisms generating such assortment, in particular when cells disperse between successive reproductive events such as happens in Dicyostelids and Myxobacteria. In this paper, we address the evolutionary dynamics of a costly trait that enhances attachment to others as well as group cohesion. By modeling cells as self-propelled particles moving on a plane according to local interaction forces and undergoing cycles of aggregation, reproduction and dispersal, we show that blind differential adhesion provides a basis for assortment in the process of group formation. When reproductive performance depends on the social context of players, evolution by natural selection can lead to the success of the social trait, and to the concomitant emergence of sizeable groups. We point out the conditions on the microscopic properties of motion and interaction that make such evolutionary outcome possible, stressing that the advent of sociality by differential adhesion is restricted to specific ecological contexts. Moreover, we show that the aggregation process naturally implies the existence of non-aggregated particles, and highlight their crucial evolutionary role despite being largely neglected in theoretical models for the evolution of sociality. © 2014 Garcia et al.

Seuret A.,Roche Holding AG | Seuret A.,Toulouse 1 University Capitole | Seuret A.,CNRS GIPSA Laboratory | Gomes Da Silva Jr. J.M.,Federal University of Rio Grande do Sul
Systems and Control Letters | Year: 2012

This paper deals with the problem of stability and stabilization of sampled-data systems under asynchronous samplings and actuator saturation. The method is based, on the one hand, on the use of a novel class of Lyapunov functionals whose derivative is negative along the trajectories of the continuous-time model of the sampled data system. It is shown that this fact guarantees that a quadratic Lyapunov function is strictly decreasing for the discrete-time asynchronous system. On the other hand, the control saturation is taken into account from the use of a generalized sector condition. These ingredients lead to the formulation of improved LMI conditions that can be cast in optimization problems aiming at enlarging estimates of the region of attraction of the closed-loop system or maximizing the bounds on the sampling period jitter for which stability and stabilization are ensured. © 2012 Elsevier B.V. All rights reserved.

Schiwietz G.,Helmholtz Center Berlin | Grande P.L.,Federal University of Rio Grande do Sul
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

Recent developments in the theoretical treatment of electronic energy losses of bare and screened ions in gases are presented. Specifically, the unitary-convolution-approximation (UCA) stopping-power model has proven its strengths for the determination of nonequilibrium effects for light as well as heavy projectiles at intermediate to high projectile velocities. The focus of this contribution will be on the UCA and its extension to specific projectile energies far below 100 keV/u, by considering electron-capture contributions at charge-equilibrium conditions. © 2011 American Physical Society.

Cavalleri A.,Federal University of Rio Grande do Sul | Mound L.A.,CSIRO
Zootaxa | Year: 2012

This paper provides an illustrated key to about 40 species of Frankliniella recorded from Brazil, together with notes about each species. Two new synonyms are established: Frankliniella longispinosa Moulton is a synonym of Frankliniella varipes Moulton; Frankliniella rodeos Moulton is a synonym of Frankliniella gemina Bagnall, all described originally from South America. One new species is described, Frankliniella graminis sp.n. is recorded from Poaceae in central and southeastern Brazil. Four species are newly recorded from Brazil: Frankliniella frumenti Moulton, Frankliniella gossypiana (Hood), Frankliniella musaeperda Hood and Frankliniella platensis De Santis.Copyright © 2012 · Magnolia Press.

Bugs G.,Federal University of Rio Grande do Sul
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

The paper assesses newest study cases in PPGIS in order to contribute to tools development that would be able to establish more appropriate practices for public participation in urban planning. By adopting previously applied comparison methodology, it assesses the usability, interactivity and functionalities of four selected online PPGIS study cases. It concentrates on online PPGIS assuming that the combination of traditional participatory methods with GIS, ICT, and the interactivity of the Web nowadays, can be of great value to make the participatory debate more democratic and consistent and, eventually, improve the levels of public participation in urban planning, strengthening the role of citizens in decision making. However, the assessment shows that online PPGIS applications are, in some aspects, limited. It is still an open question how online PPGIS should be built to face the difficulties of traditional methods and provide the proposed benefits. © 2012 Springer-Verlag.

Bini R.R.,Federal University of Rio Grande do Sul | Hume P.A.,Auckland University of Technology
International Journal of Sports Physiology and Performance | Year: 2014

The accuracy of commercial instrumented crank systems for symmetry assessment in cycling has not been fully explored. Therefore, the authors' aims were to compare peak crank torque between a commercial instrumented crank system and instrumented pedals and to assess the effect of power output on bilateral asymmetries during cycling. Ten competitive cyclists performed an incremental cycling test to exhaustion. Forces and pedal angles were recorded using right and left instrumented pedals synchronized with crank-torque measurements using an instrumented crank system. Differences in right (dominant) and left (nondominant) peak torque and asymmetry index were assessed using effect sizes. In the 100- to 250-W power-output range, the instrumented pedal system recorded larger peak torque (dominant 55-122%, nondominant 23-99%) than the instrumented crank system. There was an increase in differences between dominant and nondominant crank torque as power output increased using the instrumented crank system (7% to 33%) and the instrumented pedals (9% to 66%). Lower-limb asymmetries in peak torque increased at higher power-output levels in favor of the dominant leg. Limitations in design of the instrumented crank system may preclude the use of this system to assess peak crank-torque symmetry. © 2014 Human Kinetics, Inc.

Abramson G.,Bariloche Atomic Center | Semeshenko V.,University of Buenos Aires | Iglesias J.R.,Federal University of Rio Grande do Sul
PLoS ONE | Year: 2013

We study a simple traffic model with a non-signalized road intersection. In this model the car arriving from the right has precedence. The vehicle dynamics far from the crossing are governed by the rules introduced by Nagel and Paczuski, which define how drivers behave when braking or accelerating. We measure the average velocity of the ensemble of cars and its flow as a function of the density of cars on the roadway. An additional set of rules is defined to describe the dynamics at the intersection assuming a fraction of drivers that do not obey the rule of precedence. This problem is treated within a game-theory framework, where the drivers that obey the rule are cooperators and those who ignore it are defectors. We study the consequences of these behaviors as a function of the fraction of cooperators and defectors. The results show that cooperation is the best strategy because it maximizes the flow of vehicles and minimizes the number of accidents. A rather paradoxical effect is observed: for any percentage of defectors the number of accidents is larger when the density of cars is low because of the higher average velocity. © 2013 Abramson et al.

Bazzan A.L.C.,Federal University of Rio Grande do Sul
Proceedings of the International Joint Conference on Neural Networks | Year: 2012

Learning in coordination games has been extensively studied in the game theory and multi-agent learning literature. Most of this work has considered a low number of agents and/or states (typically two agent, two action games). When the number of states and/or joint actions increases, standard approaches for multi-agent learning have difficulties coping with a high number of agents due to the combinatorial explosion in the number of joint actions and joint states. In real-world applications, this is a common setting though. This paper introduces a methodology for learning to coordinate in stochastic games with many agents. More specifically, we introduce a structure where some agents have knowledge about joint actions and how they have performed in the past. We empirically investigate this method for multi-agent learning in a typical stochastic game involving a high number of agents. Experimental results show that the additional information and structure is translated into earlier and higher levels of coordination and thus to higher payoffs. © 2012 IEEE.

Ames J.,Grande Rio University | Ames J.,Federal University of Rio de Janeiro | Souza D.Z.,Federal University of Rio Grande do Sul
Revista de Saude Publica | Year: 2012

Objective: To identify the main counterfeit drugs seized by the Brazilian Federal Police and the states where seizures have been made. Methods: A retrospective descriptive study on expert reports produced by criminal investigators of the Federal Police between January 2007 and September 2010, in relation to counterfeit drugs, was carried out. Results: The drugs with greatest numbers of seizures were selective phosphodiesterase-5 inhibitors that are used for treating male erectile dysfunction (Cialis® and Viagra®, mean = 66%), followed by anabolic steroids (Durateston® and Hemogenin®: 8.9% and 5.7%, respectively). The greatest proportions of the counterfeit drugs were seized in the states of Paraná, Santa Catarina (both Southeastern Brazil) and São Paulo (Southeastern), and the number of non-authentic drugs sent for investigation increased by more than 200% over the study period. There were increases in seizures of smuggled drugs found together with counterfeit drugs: 67% of the seizures included at least one smuggled drug. Conclusions: Counterfeiting of drugs is a severe public health problem. Identifi cation of the classes of counterfeit drugs present in Brazil and the main Brazilian states with this problem may facilitate future preventive and suppressive actions by the Brazilian bodies responsible for such actions.

Vedolin L.,Federal University of Rio Grande do Sul
Topics in Magnetic Resonance Imaging | Year: 2011

Inherited white matter disorders of childhood (WMDC) refer to a broad group of progressive inherited disorders that exclusively or predominantly affect myelin formation and/or maintenance. They are often in the form of neurological deficits, developmental delay, or frank encephalopathy and are difficult to diagnose clinically. The imaging diagnostic approach for the WMDC is difficult and demands knowledge of neuroimaging features, age of onset of the disease, genetic pattern, and recognition of the most important clinical findings. Unfortunately, the variability and evolving patterns of imaging findings, combined with the continual discovery of new metabolic diseases, make establishing a diagnosis difficult for radiologists who lack experience in the imaging of suspected metabolic diseases. The goal of this article was to present a structured neuroimaging approach to inheritedWMDC based on the most discriminating magnetic resonance imaging features as the starting point to create a list of the most probable diagnoses. © 2013 by Lippincott Williams & Wilkins.

Souza S.R.,Federal University of Rio de Janeiro | Souza S.R.,Federal University of Rio Grande do Sul | Tsang M.B.,Michigan State University
Physical Review C - Nuclear Physics | Year: 2012

The properties of isobaric ratios, between nuclei produced in the same reaction, are investigated using the canonical and grand-canonical statistical ensembles. Although the grand-canonical formulas furnish a means to correlate the ratios with the liquid drop parameters, finite size effects make it difficult to obtain their actual values from fitting nuclear collision data. © 2012 American Physical Society.

Brouzos I.,University of Ulm | Foerster A.,Federal University of Rio Grande do Sul
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2014

We show that the breaking of integrability in the fundamental one-dimensional model of bosons with contact interactions has consequences on the stationary correlation properties of the system. We calculate the energies and correlation functions of the integrable Lieb-Liniger case, comparing the exact Bethe-ansatz solution with a corresponding Jastrow ansatz. Then we examine the nonintegrable case of different interaction strengths between each pair of atoms by means of a variationally optimized Jastrow ansatz, proposed in analogy to the Laughlin ansatz. We show that properties of the integrable state are more stable close to the Tonks-Girardeau regime than for weak interactions. All energies and correlation functions are given in terms of explicit analytical expressions enabled by the Jastrow ansatz. We finally compare the correlations of the integrable and nonintegrable cases and show that apart from symmetry breaking the behavior changes dramatically, with additional and more pronounced maxima and minima interference peaks appearing. © 2014 American Physical Society.

Bica O.C.,Santa Cecilia University | Giugliani E.R.J.,Federal University of Rio Grande do Sul
Birth | Year: 2014

Background: Adolescent mothers living with their mothers may be at greater risk of early weaning. This study aims to assess the influence of a breastfeeding promotion strategy directed at adolescent mothers living with their mothers on the prevalence of breastfeeding in the first year of life. Method: A randomized clinical trial with 323 adolescent mothers. Participants were divided into two groups: those who lived with their mothers and those who did not. Participants were randomly assigned to control or intervention groups. Intervention consisted of breastfeeding counseling sessions held at the maternity ward and at home (at 7, 15, 30, 60, and 120 days postpartum). The intervention effect was assessed by comparing survival curves for breastfeeding in the first 12 months of life. Results: The risk of weaning before 12 months of age was significantly lower in the intervention group for adolescent mothers not living with their mothers; whereas the risk was not statistically different between intervention and control groups for those living with their mothers. Conclusions: The positive influence of systematic counseling sessions on the prevalence of breastfeeding in the first year of life was significant for adolescent mothers. Living with their mothers reduced such influence. © 2014, Wiley Periodicals, Inc.

Da Costa S.A.,Federal University of Pelotas | Ribeiro L.,Federal University of Rio Grande do Sul
Science of Computer Programming | Year: 2012

Graph grammars may be used as specification technique for different kinds of systems, specially in situations in which states are complex structures that can be adequately modeled as graphs (possibly with an attribute data part) and in which the behavior involves a large amount of parallelism and can be described as reactions to stimuli that can be observed in the state of the system. The verification of properties of such systems is a difficult task due to many aspects: the systems in many situations involve an infinite number of states; states themselves are complex and large; there are a number of different computation possibilities due to the fact that rule applications may occur in parallel. There are already some approaches to verification of graph grammars based on model checking, but in these cases only finite state systems can be analyzed. Other approaches propose over- and/or under-approximations of the state space, but in this case it is not possible to check arbitrary properties. This work proposes a relational and logical approach to graph grammars that allows formal verification of systems using mathematical induction. We use relational structures to define graph grammars and first-order logic to model graph transformations. This approach allows proving properties of systems with infinite state spaces. In this paper we first consider the case of simple (typed) graphs, and then we extend the approach to the non-trivial case of attributed graphs, that are graphs in which values are associated to vertices. Attributed graph grammars are very interesting from a practical point of view, since it is possible to use variables and terms when specifying the behavior expressed by rules. These values (or terms) come from algebras specified as abstract data types. The use of attributed graphs gives the specifier a language that is more suitable for specification, merging the advantages of the graphical representation with the standard representation of classical data types. We show that attributes can be smoothly integrated in our representation of graph grammars, giving rise to a framework to reason about attributed graph grammars. © 2010 Elsevier B.V. All rights reserved.

Newsholme P.,Curtin University Australia | De Bittencourt P.I.H.,Federal University of Rio Grande do Sul | De Bittencourt P.I.H.,National Institute of Hormones and Womens Health
Current Opinion in Clinical Nutrition and Metabolic Care | Year: 2014

Obesity is a chronic inflammatory disease in which the physiological resolution of inflammation is attenuated, leading to low-grade inflammation throughout the body. However, the heat shock response, which is a key component of the physiological response to resolve inflammation, is seriously hampered in adipose tissue and other metabolic organs (e.g. skeletal muscle, liver, pancreatic β-cells) in metabolic diseases. In this review, we hypothesize that adipocyte metabolic stress triggers the onset of fat cell senescence, and companion senescence-Associated secretory phenotype (SASP), and that such a scenario is responsible for attenuating the resolution of inflammation. RECENT FINDINGS: We shall discuss the role of the heat shock response in the context of the resolution of inflammation and the relevance of heat shock response blockade in chronic inflammatory diseases. Sirtuin-1 is responsible for the induction of heat shock transcription factor-1 mRNA expression and for the stabilization of heat shock transcription factor-1 in a high-profile activity state. However, adipose tissue-emanated SASP depress sirtuin-1 expression, leading adipocytes to a perpetual state of unresolved inflammation, due to a dampening of the heat shock response. SUMMARY: The advance of inflammasome-mediated SASP from adipose to other tissues promotes cellular senescence in many other cells of the organism, aggravating obesity-dependent chronic inflammation. Inducers of heat shock response (e.g. heat shock itself, physical exercise and calorie restriction) may efficiently interrupt this vicious cycle and are envisaged as the best and also the most economical treatment for obesity-related chronic diseases.Copyright © Lippincott Williams &Wilkins.

Netz P.A.,Federal University of Rio Grande do Sul
International Journal of Quantum Chemistry | Year: 2012

Some organic dyes, derivatives of the 4-(arylethynyl)-7-(4-methoxyphenyl)- 2,1,3-benzothiadiazoles (BTDs) bind strongly to double stranded DNA, exhibiting a strong increase in the fluorescence intensity. Due to this property, they were proposed as very sensitive probes for DNA detection and quantification. The details of the interaction mechanism, however, are unknown. In this work, we use docking and molecular dynamics simulations to study the interactions of these BTDs with DNA. We used a docking protocol where the receptor is a modified canonical oligonucleotide, with a gap, to sample intercalation and minor groove binding modes. Starting from several independent but energetically favorable docking poses, molecular dynamics simulations were carried out, investigating the ligand-DNA interactions and the time evolution of the DNA structure. We observed, in agreement with experimental results, that the presence of the ethynyl spacer in the ligand stabilizes the intercalation binding mode, yielding strong interactions with DNA and large residence times. © 2012 Wiley Periodicals, Inc.

Riera J.D.,Federal University of Rio Grande do Sul
Structural Safety | Year: 2010

The authors recently proposed a model of the 3-D wind field in a thunderstorm event, which is characterized by a set of parameters that are defined as random variables with physical significance in meteorology. On the basis of the information available to the authors, tentative statistical models for these variables are suggested and adopted in a simulation study to obtain peak annual velocities at the locations of two meteorological stations where observational data is available. Comparison of probability density functions of the maximum annual TS wind velocities fitted to the simulated and recorded data led to encouraging results, suggesting that the approach may have extensive applications in wind engineering and reliability assessments. © 2010 Elsevier Ltd.

Sanhudo J.A.V.,Mae de Deus Hospital | Ellera Gomes J.L.,Federal University of Rio Grande do Sul
Foot and Ankle Clinics | Year: 2012

Plantar plate rupture is a common cause of forefoot pain, multiplanar malalignment, subluxation, or dislocation of the metatarsophalangeal joint (MTPJ). The treatments that have been described for MTPJ instability of lesser toes include amputation, lengthening and/or tendon transfer, periarticular soft-tissue release (capsule, collateral ligaments, and plantar plate), colateral ligament reconstruction, metatarsal shortening osteotomy, and suture of plantar plate lesion. This article outlines the anatomy, pathogenesis, and diagnosis of plantar plate rupture, and describes a new technique that combines joint decompression by Weil osteotomy with a plantar plate repair using a pull-out technique. © 2012 Elsevier Inc.

Barbosa O.,Industrial University of Santander | Torres R.,Industrial University of Santander | Ortiz C.,Industrial University of Santander | Berenguer-Murcia A.,Instituto Universitario Of Materiales | And 2 more authors.
Biomacromolecules | Year: 2013

A heterofunctional support for enzyme immobilization may be defined as that which possesses several distinct functionalities on its surface able to interact with a protein. We will focus on those supports in which a final covalent attachment between the enzyme and the support is achieved. Heterofunctionality sometimes has been featured in very old immobilization techniques, even though in many instances it has been overlooked, giving rise to some misunderstandings. In this respect, glutaraldehyde-activated supports are the oldest multifunctional supports. Their matrix has primary amino groups, the hydrophobic glutaraldehyde chain, and can covalently react with the primary amino groups of the enzyme. Thus, immobilization may start (first event of the immobilization) via different causes and may involve different positions of the enzyme surface depending on the activation degree and immobilization conditions. Other "classical" heterofunctional supports are epoxy commercial supports consisting of reactive covalent epoxy groups on a hydrophobic matrix. Immobilization is performed at high ionic strength to permit protein adsorption, so that covalent attachment may take place at a later stage. Starting from these old immobilization techniques, tailor-made heterofunctional supports have been designed to permit a stricter control of the enzyme immobilization process. The requirement is to find conditions where the main covalent reactive moieties may have very low reactivity toward the enzyme. In this Review we will discuss the suitable properties of the groups able to give the covalent attachment (intending a multipoint covalent attachment), and the groups able to produce the first enzyme adsorption on the support. Prospects, limitations, and likely pathways for the evolution (e.g., coupling of site-directed mutagenesis and thiol heterofunctional supports of enzyme immobilization on heterofunctional supports) will be discussed in this Review. © 2013 American Chemical Society.

Moreno J.,National University of Colombia | Ovalle D.A.,National University of Colombia | Vicari R.M.,Federal University of Rio Grande do Sul
Computers and Education | Year: 2012

Considering that group formation is one of the key processes in collaborative learning, the aim of this paper is to propose a method based on a genetic algorithm approach for achieving inter-homogeneous and intra-heterogeneous groups. The main feature of such a method is that it allows for the consideration of as many student characteristics as may be desired, translating the grouping problem into one of multi-objective optimization. In order to validate our approach, an experiment was designed with 135 college freshmen considering three characteristics: an estimate of student knowledge levels, an estimate of student communicative skills, and an estimate of student leadership skills. Results of such an experiment allowed for the validation, not only from the computational point of view by measuring the algorithmic performance, but also from the pedagogical point of view by measuring student outcomes, and comparing them with two traditional group formation strategies: random and self-organized. © 2011 Elsevier Ltd. All rights reserved.

Schneck F.,Federal University of Rio Grande do Sul | Melo A.S.,Federal University of Goais
Freshwater Biology | Year: 2013

1.The persistence of biological assemblages is positively affected by spatial heterogeneity. This influence may be indirect, through increased species richness. Another possibility is the increased availability of refuges from disturbances, which would prevent local loss. 2.We conducted a field experiment to test the hypothesis that greater roughness (a form of spatial heterogeneity) on the surface of substrata allows higher persistence of assemblages of stream benthic algae and that this relationship does not depend on species richness. Samples were taken on six occasions from smooth and rough artificial substrata used for algal colonisation. We calculated the persistence of assemblages using two analytical approaches: the mean distance to group centroid and the sum of the Euclidean distances between consecutive sampling occasions, both in a multivariate space. We also subsampled the data to take into account differences in species richness between treatments and thus to evaluate the effect of species richness on persistence. 3.Assemblages on rough substrata were more persistent than assemblages on smooth substrata. The effects detected were not due to the greater species richness on rough substrata, since a higher persistence of the assemblages on rough substrata remained after the subsampling procedures. 4.Our results indicate a strong positive relationship between substratum roughness and the persistence of stream benthic algal assemblages. We suggest that this is due to the presence of physical refuges in heterogeneous habitats. © 2012 Blackwell Publishing Ltd.

Bazanella A.S.,Federal University of Rio Grande do Sul | Gevers M.,Catholic University of Louvain | Miskovic L.,Ecole Polytechnique Federale de Lausanne
European Journal of Control | Year: 2010

This paper addresses a question that has been posed to us: "Is it necessary to excite all reference signals for the identification of a multivariable system operating in closed loop with a linear time-invariant controller?" In this paper, we follow a careful re-examination of the otions of identifiability and informative experiments or multi-input multi-output (MIMO) closed-loop ystems, which provides a negative answer to this uestion. Our analysis also allows to establish conditions n the controller complexity that guarantee xistence of a unique global minimum of the identification riterion in the absence of external excitation; hese conditions extend to the MIMO case conditions hat were known for the SISO case. We illustrate our esults for 2-input 2-output systems by presenting arious possible experiment designs that produce a nique global minimum for the identification criterion. © 2010 EUCA.

De Faria Poloni J.,University of Caxias do Sul | Feltes B.C.,University of Caxias do Sul | Bonatto D.,Federal University of Rio Grande do Sul
Functional and Integrative Genomics | Year: 2011

Melatonin (MEL) is a neuroendocrine hormone secreted by the pineal gland in association with the suprachiasmatic nucleus and peripheral tissues. MEL has been observed to play a critical role in the reproductive process and in the fetomaternal interface. Extrapineal synthesis has been reported inmammalian models during pregnancy, especially by the placenta tissue. MEL can regulate intracellular processes (e.g., G-proteins) and the activity of second messengers (e.g., cAMP, IP 3, Ca 2+). During neurodevelopment, these activities regulated by melatonin have an important role as an intracellular signaling for gene expression regulation. To review the role of MEL in neurodevelopment, we built interactome networks of different proteins that act in these processes using systems biology tools. The analyses of interactome networks revealed that MEL could modulate neurodevelopment through the regulation of Ca 2+ intracellular levels and influencing BMP/SMAD signaling, thus affecting neural gene responses and neuronal differentiation. © Springer-Verlag 2011.

Soares R.D.P.,Federal University of Rio Grande do Sul
Computers and Chemical Engineering | Year: 2013

Chemical engineering is a rich area when comes to nonlinear systems of equations, possibly with multiple solutions, (unbounded) discontinuities, or functions which become undefined in terms of real values. In this work, a new approach is proposed for finding all real solutions of such systems within prescribed bounds. A modified affine arithmetic is used in an interval Newton method plus generalized bisection. A special constraint propagation is used to automatically remove regions where the functions are undefined for real numbers. Results for test problems have shown that the proposed implementation requires less computation effort than similar methods available in the literature for small continuous systems. Further, the method is able to find all real solutions of nonlinear systems of equations even when there are unbounded discontinuities or when functions become undefined within the given variable bounds. © 2012 Elsevier Ltd.

Storchi-Bergmann T.,Federal University of Rio Grande do Sul
Brazilian Journal of Physics | Year: 2013

A fundamental role is attributed to supermassive black holes (SMBH), and the feedback they generate, in the evolution of galaxies. But theoretical models trying to reproduce the MSMBH vs. sigma relation (between the SMBH mass and stellar velocity dispersion of the galaxy bulge) make broad assumptions about the physical processes involved. These assumptions are needed due to the scarcity of observational constraints on the relevant physical processes which occur when the SMBH is being fed via mass accretion in active galactic nuclei (AGN). In search for these constraints, our group-AGN integral field spectroscopy (AGNIFS)-has been mapping the gas kinematics as well as the stellar population properties of the inner few hundred parsecs of a sample of nearby AGN hosts. In this contribution, I report on results obtained so far which show gas inflows along nuclear spirals and compact disks in the inner tens to hundreds of pc in nearby AGN hosts which seem to be the sources of fuel to the AGN. As the inflow rates are much larger than the AGN accretion rate, the excess gas must be depleted via formation of new stars in the bulge. Indeed, in many cases, we find ∼100 pc circumnuclear rings of recent star formation (ages ∼10-500 Myr) that can be interpreted as a signature of coevolution of the host galaxy and its AGN. I also report on the mapping of outflows in ionized gas, which are ubiquitous in Seyfert galaxies, and discuss mass outflow rates and powers. © 2013 Sociedade Brasileira de Física.

Lopes R.P.,Federal University of Rio Grande do Sul
Journal of Mammalian Evolution | Year: 2013

Fossils of Pleistocene mammals have been discovered in the southern Brazilian coastal area since the late XIX century, in two main places: the continental shelf and the Chuí Creek. Although the taxonomic composition of fossil assemblages from these areas has been the focus of most studies during the late XX century, research concerning the ages, stratigraphic position, and biostratigraphy of such assemblages remains scarce. This is due to the lack of suitable materials for age determination and the reworked nature of the fossiliferous deposits in the continental shelf. Only in recent years have new data shed light on these subjects. Taxonomic revisions, ESR ages, and biostratigraphic correlations confirm a late Pleistocene age for the fossil assemblages, although those from the shelf represent a significant time averaging, while fossils from the Chuí Creek exhibit a narrower age range. The fossil mammals found in southern Brazil represent a mixture of Brazilian and Pampean taxa, including forms that disappeared much earlier from the Argentinean pampas. Gaining an understanding of the biostratigraphic context of such assemblages in comparison to similar assemblages from Argentina and Uruguay, in conjunction with stratigraphic, geomorphological, and paleoclimatic data should provide additional tools with which to reconstruct the environmental and climatic dynamics of this portion of South America during the late Pleistocene-early Holocene and its effects on the fauna, and possibly to help address the problem of the disappearance of megamammals in the area. © 2011 Springer Science+Business Media, LLC.

Gallon C.W.,University of Caxias do Sul | Wender M.C.O.,Federal University of Rio Grande do Sul
Revista Brasileira de Ginecologia e Obstetricia | Year: 2012

PURPOSE: To associate the quality of life with the nutritional status of climacteric women. METHODS: This was a cross sectional study on a sample of 200 climacteric women aged 40 to 65 years who responded to a 24-hour food recall and to questions about socioeconomic factors and current, previous and family medical history. Body mass index (BMI), waist circumference (WC) and waist-hip ratio were used for anthropometric evaluation. To assess the quality of life, we applied the MRS-menopause rating scale. RESULTS: The average BMI and waist circumference were 30.1 kg/m 2 (obesity grade 1) and 99 cm (very increased risk for cardiovascular disease), respectively. Increased protein consumption and decreased fiber, calcium and vitamin D intake were detected. The most prevalent disease was hypertension, 48.5% of the women studied were taking medication for cardiovascular disease and 23% were taking antidepressant medications. Regarding quality of life, significant results related to BMI as well as blood pressure were found. CONCLUSIONS: A nutritional intervention aiming to correct or improve food consumption and anthropometric profile may result in health benefits for climacteric women. The prevalence of obesity, associated with a poorer quality of life, morbidity and mortality underscores the need for a feeding re-education program during the climacteric.

Objective: Verify if there is a relationship between crack craving increase and tobacco craving increase in patients hospitalized for detoxification. Method: Quasi-experimental clinical trial using a quantitative analysis. Sample comprised 32 crack-cocaine and tobacco-dependent males, in 2 to 3 weeks of abstinence. A group intervention was conducted to which initially Cocaine Craving Questionnaire-Brief (CCQB), QSUB (Questionnaire of Smoking Urges-Brief) and BAI (Beck Anxiety Inventory) were applied. Next, crack related images were applied and CCQB, QSUB and BAI were re-applied. After that, an individual interview was conducted in which a form containing sociodemo-graphic information and data related to the pattern of consumption of psychoactive substances (FSD) and Fagerström Test for Nicotine Dependence (FTND) were applied. Results: Following the crack related images exposure, there was a significant increase of crack craving, tobacco craving and anxiety symptoms, being them positively correlated. Conclusion: Results show a significant association between crack craving and tobacco craving, suggesting that tobacco abstinence can help on effectiveness of cocaine dependence treatment.

Sanguinetti A.,University of Buenos Aires | Sanguinetti A.,CONICET | Singer R.B.,Federal University of Rio Grande do Sul
Biological Conservation | Year: 2014

Most non-autogamous orchids rely on either a single, or on a small number of pollinators to set fruit. The nectar-rewarding orchid Brachystele unilateralis and the nectarless and deceit-pollinated Chloraea virescens are restricted to the Southern Andes, where a single native and endemic bumblebee (Bombus dahlbomii) occured until the introduction of honeybees and highly invasive European bumblebees. Here, we describe the floral features, breeding system, pollinator activity and fruiting success of these orchid species. Both are self-compatible but pollinator-dependent, i.e., unable to set fruit and seed in the absence of pollinators. Field observations revealed that most of their current reproductive success is due to the introduced Bombus terrestris, Bombus ruderatus and Apis mellifera bees. The only native pollinator recorded was B. dahlbomii, but this bee was rarely observed due to its steady decline since the introduction of the alien Bombus species. The observed natural fruiting success per inflorescence in both studied species proved to be remarkably high by orchid standards: 83% and 66%, respectively. These results suggest that sexual reproduction in these orchids is not necessarily threatened by the decline of their native pollinator since pollination is successfully achieved by introduced bees. This provides a plausible better outlook for these and other regional, bumblebee-pollinated orchids and raises caution on eventual conservation policies involving the management of these introduced bee species. To our knowledge, this is the first report of native orchid pollinators being effectively replaced by invasive bumblebees and, furthermore, the first description of the pollination biology of a species of Brachystele. © 2014 Elsevier Ltd.

Wehrmeister M.A.,Santa Catarina State University | Pereira C.E.,Federal University of Rio Grande do Sul | Rammig F.J.,University of Paderborn
IEEE Transactions on Industrial Informatics | Year: 2013

Automation and control systems include many 'intelligent' automation devices, which are usually implemented as complex embedded systems. New methods and tools are demanded to cope with the increasing design complexity, while keeping the project on schedule. Proper handling of nonfunctional system requirements is a key factor during the design of industrial automation systems, since in some application domains they are as important as (sometimes, more important than) functional requirements. This paper presents a model-driven engineering approach, which combines Unified Modeling Language (UML) and aspect-oriented software development (AOSD) to design real-time and embedded automation systems. The proposed approach allows a smooth transition from the initial phases to implementation by using software tools, comprising the system specification and the automatic generation of source code. By combining UML with model-level aspects and a script-base code generation tool, it enables the use of AOSD during system design and implementation, even though the target platform does not natively support such concepts. Experimental results on using this approach to design real-world examples of automation systems are presented. The results indicate a positive impact on the design of automation systems. The encapsulation of nonfunctional requirements was improved, increasing the reuse of developed artifacts. Generated source code statistics indicate that the proposed approach can generated a fair amount of code per model element. © 2013 IEEE.

Lemaire G.,French National Institute for Agricultural Research | Franzluebbers A.,U.S. Department of Agriculture | Carvalho P.C.D.F.,Federal University of Rio Grande do Sul | Dedieu B.,French National Institute for Agricultural Research
Agriculture, Ecosystems and Environment | Year: 2014

A need to increase agricultural production across the world for food security appears to be at odds with the urgency to reduce agriculture's negative environmental impacts. We suggest that a cause of this dichotomy is loss of diversity within agricultural systems at field, farm and landscape scales. To increase diversity, local integration of cropping with livestock systems is suggested, which would allow (i) better regulation of biogeochemical cycles and decreased environmental fluxes to the atmosphere and hydrosphere through spatial and temporal interactions among different land-use systems; (ii) a more diversified and structured landscape mosaic that would favor diverse habitats and trophic networks; and (iii) greater flexibility of the whole system to cope with potential socio-economic and climate change induced hazards and crises. The fundamental role of grasslands on the reduction of environmental fluxes to the atmosphere and hydrosphere operates through the coupling of C and N cycles within vegetation, soil organic matter and soil microbial biomass. Therefore, close association of grassland systems with cropping systems should help mitigate negative environmental impacts resulting from intensification of cropping systems and improve the quality of grasslands through periodic renovations. However, much research is needed on designing appropriate spatial and temporal interactions between these systems using contemporary technologies to achieve the greatest benefits in different agro-ecological regions. We postulate that development of modern integrated crop-livestock systems to increase food production at farm and regional levels could be achieved, while improving many ecosystem services. Integrated crop-livestock systems, therefore, could be a key form of ecological intensification needed for achieving future food security and environmental sustainability. © 2013 Elsevier B.V.

Blonde L.,Ochsner Medical Center | Jendle J.,Orebro University | Gross J.,Federal University of Rio Grande do Sul | Woo V.,University of Manitoba | And 3 more authors.
The Lancet | Year: 2015

Background For patients with type 2 diabetes who do not achieve target glycaemic control with conventional insulin treatment, advancing to a basal-bolus insulin regimen is often recommended. We aimed to compare the efficacy and safety of long-acting glucagon-like peptide-1 receptor agonist dulaglutide with that of insulin glargine, both combined with prandial insulin lispro, in patients with type 2 diabetes. Methods We did this 52 week, randomised, open-label, phase 3, non-inferiority trial at 105 study sites in 15 countries. Patients (aged ≥18 years) with type 2 diabetes inadequately controlled with conventional insulin treatment were randomly assigned (1:1:1), via a computer-generated randomisation sequence with an interactive voice-response system, to receive once-weekly dulaglutide 1·5 mg, dulaglutide 0·75 mg, or daily bedtime glargine. Randomisation was stratified by country and metformin use. Participants and study investigators were not masked to treatment allocation, but were unaware of dulaglutide dose assignment. The primary outcome was a change in glycated haemoglobin A1c (HbA1c) from baseline to week 26, with a 0·4% non-inferiority margin. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01191268. Findings Between Dec 9, 2010, and Sept 21, 2012, we randomly assigned 884 patients to receive dulaglutide 1·5 mg (n=295), dulaglutide 0·75 mg (n=293), or glargine (n=296). At 26 weeks, the adjusted mean change in HbA1c was greater in patients receiving dulaglutide 1·5 mg (-1·64% [95% CI -1·78 to -1·50], -17·93 mmol/mol [-19·44 to -16·42]) and dulaglutide 0·75 mg (-1·59% [-1·73 to -1·45], -17·38 mmol/mol [-18·89 to -15·87]) than in those receiving glargine (-1·41% [-1·55 to -1·27], -15·41 mmol/mol [-16·92 to -13·90]). The adjusted mean difference versus glargine was -0·22% (95% CI -0·38 to -0·07, -2·40 mmol/mol [-4·15 to -0·77]; p=0·005) for dulaglutide 1·5 mg and -0·17% (-0·33 to -0·02, -1·86 mmol/mol [-3·61 to -0·22]; p=0·015) for dulaglutide 0·75 mg. Five (<1%) patients died after randomisation because of septicaemia (n=1 in the dulaglutide 1·5 mg group); pneumonia (n=1 in the dulaglutide 0·75 mg group); cardiogenic shock; ventricular fibrillation; and an unknown cause (n=3 in the glargine group). We recorded serious adverse events in 27 (9%) patients in the dulaglutide 1·5 mg group, 44 (15%) patients in the dulaglutide 0·75 mg group, and 54 (18%) patients in the glargine group. The most frequent adverse events, arising more often with dulaglutide than glargine, were nausea, diarrhoea, and vomiting. Interpretation Dulaglutide in combination with lispro resulted in a significantly greater improvement in glycaemic control than did glargine and represents a new treatment option for patients unable to achieve glycaemic targets with conventional insulin treatment. Funding Eli Lilly and Company. © 2015 Elsevier Ltd.

Volpato G.,Quatro G Pesquisa e Desenvolvimento Ltda. | Rodrigues R.C.,Federal University of Rio Grande do Sul | Fernandez-Lafuente R.,Institute Catalisis CSIC
Current Medicinal Chemistry | Year: 2010

Semi-synthetic β-lactamic antibiotics are the most used anti-bacteria agents, produced in hundreds tons/year scale. It may be assumed that this situation will even increase during the next years, with new β-lactamic antibiotics under development. They are usually produced by the hydrolysis of natural antibiotics (penicillin G or cephalosporin C) and the further amidation of natural or modified antibiotic nuclei with different carboxylic acyl donor chains. Due to the contaminant reagents used in conventional chemical route, as well as the high energetic consumption, biocatalytic approaches have been studied for both steps in the production of these very interesting medicaments during the last decades. Recent successes in some of these methodologies may produce some significant advances in the antibiotics industry. In fact, the hydrolysis of penicillin G to produce 6-APA catalyzed by penicillin G acylase is one of the most successful historical examples of the enzymatic biocatalysis, and much effort has been devoted to find enzymatic routes to hydrolyze cephalosporin C. Initially this could be accomplished in a quite complex system, using a two enzyme system (D-amino acid oxidase plus glutaryl acylase), but very recently an efficient cephalosporin acylase has been designed by genetic tools. Other strategies, including metabolic engineering to produce other antibiotic nuclei, have been also reported. Regarding the amidation step, much effort has been devoted to the improvement of penicillin acylases for these reactions since 1960. New reaction strategies, continuous product extraction or new penicillin acylases with better properties have proven to be the key to have competitive biocatalytic processes. In this review, a critical discussion of these very interesting advances in the application of enzymes for the industrial synthesis of semi-synthetic antibiotics will be presented. © 2010 Bentham Science Publishers Ltd.

Brunoni A.R.,University of Sao Paulo | Schestatsky P.,Federal University of Rio Grande do Sul | Schestatsky P.,EMG Unit | Lotufo P.A.,University of Sao Paulo | And 2 more authors.
Clinical Neurophysiology | Year: 2014

Objective: To compare blinding integrity and associated factors for transcranial direct current stimulation (tDCS) vs. placebo-pill, the gold standard blinding method. Methods: Parallel trial. Depressed participants were randomized to verum/placebo sertraline and active/sham tDCS (2. mA, 30-min 10-daily sessions and two additional, fortnight sessions) over 6. weeks. Blinding was assessed in completers (n=102) and in a random subgroup (n=35) of raters and participants, in which we also inquired to qualitatively describe their strongest guessing reason. Results: Participants and raters presented similar performance for predicting treatment assignment at endpoint, correctly guessing tDCS and sertraline beyond chance. Nevertheless, clinical response was associated with correct prediction and tDCS non-responders failed to predict the allocation group. For tDCS, ". trouble concentrating" was inversely associated with correct prediction. ". Skin redness" was more reported for active-tDCS, but did not predict the allocation group. The qualitative reasons for raters' guessing were not associated with correct prediction, whereas for participants clinical response and adverse effects were directly and inversely associated with correct prediction, respectively. Conclusion: Blinding integrity of tDCS and sertraline were comparable and mainly associated with efficacy rather than blinding failure. Significance: TDCS blinding can be improved by adopting parallel designs and avoiding subjects' awareness of skin redness. © 2013 International Federation of Clinical Neurophysiology.

Teixeira F.G.,Federal University of Rio Grande do Sul | Da Silva L.F.M.,University of Porto
Journal of Adhesion | Year: 2011

This paper analyses the influence of surface roughness on adhesive bond strength. Numerical simulations were performed to evaluate the influence of geometry on the performance of structural adhesive joints. The objective is to create a model to describe the behaviour of the interphase of adhesive joints according to its geometry. Two-dimensional simulations with theoretical geometries were performed considering parameters of roughness, stress distribution, and contact area to verify the qualitative influence of substrate topography on the adhesion of a joint. Numerical analyses were done to verify the effect of the interpenetration of materials on the mechanical properties of the interphase. Copyright © Taylor & Francis Group, LLC.

Rodrigues R.C.,Federal University of Rio Grande do Sul | Ortiz C.,Industrial University of Santander | Berenguer-Murcia A.,University of Alicante | Torres R.,Industrial University of Santander | Fernandez-Lafuente R.,Institute Catalisis CSIC
Chemical Society Reviews | Year: 2013

Immobilization of enzymes may produce alterations in their observed activity, specificity or selectivity. Although in many cases an impoverishment of the enzyme properties is observed upon immobilization (caused by the distortion of the enzyme due to the interaction with the support) in some instances such properties may be enhanced by this immobilization. These alterations in enzyme properties are sometimes associated with changes in the enzyme structure. Occasionally, these variations will be positive. For example, they may be related to the stabilization of a hyperactivated form of the enzyme, like in the case of lipases immobilized on hydrophobic supports via interfacial activation. In some other instances, these improvements will be just a consequence of random modifications in the enzyme properties that in some reactions will be positive while in others may be negative. For this reason, the preparation of a library of biocatalysts as broad as possible may be a key turning point to find an immobilized biocatalyst with improved properties when compared to the free enzyme. Immobilized enzymes will be dispersed on the support surface and aggregation will no longer be possible, while the free enzyme may suffer aggregation, which greatly decreases enzyme activity. Moreover, enzyme rigidification may lead to preservation of the enzyme properties under drastic conditions in which the enzyme tends to become distorted thus decreasing its activity. Furthermore, immobilization of enzymes on a support, mainly on a porous support, may in many cases also have a positive impact on the observed enzyme behavior, not really related to structural changes. For example, the promotion of diffusional problems (e.g., pH gradients, substrate or product gradients), partition (towards or away from the enzyme environment, for substrate or products), or the blocking of some areas (e.g., reducing inhibitions) may greatly improve enzyme performance. Thus, in this tutorial review, we will try to list and explain some of the main reasons that may produce an improvement in enzyme activity, specificity or selectivity, either real or apparent, due to immobilization. © 2013 The Royal Society of Chemistry.

Pistor V.,Federal University of Rio Grande do Sul | Zattera A.J.,University of Caxias do Sul
Journal of Elastomers and Plastics | Year: 2014

The reclaiming of elastomer residues is one of the main problems of recycling materials. In this work, the efficiency of devulcanization of recycled ethylene propylene diene terpolymer (EPDM) was determined by subjecting the elastomer samples to 2, 3 and 4 min of microwaves exposure. Scanning electron microscopy and thermogravimetric analysis using different heating rates to determine the kinetic degradation parameters according to the Flynn-Wall-Ozawa and Criado methods were studied. The results obtained showed that up to 4 min devulcanization exposure period, the degradation temperature of EPDM did not exceed. Microwaves exposure caused modifications in the morphology and reduction in activation energy values upon increased samples exposure period. Degradation mechanisms were altered, mainly for the 4-min exposure period, where the nucleation mechanism shifts to diffusion, suggesting that the microwave method was able to promote the breakage of the elastomeric three-dimensional network. © The Author(s) 2012.

Valentini N.C.,Federal University of Rio Grande do Sul
Journal of Motor Behavior | Year: 2012

The Test of Gross Motor Development (TGMD-2) is broadly used in research and clinical settings. The author aimed to translate and investigate the content, criteria, and construct validity and reliability of the TGMD-2 for Brazilian children. The study involved translators, experts, and 3,124 Brazilian children from several states of Brazil. Results confirmed language clarity and pertinence of the TGMD-2. Appropriate indices of the confirmatory factorial validity (root mean square error of approximation =.06; comparative fit index =.88; Tucker-Lewis index =.83; normed fit index =.09; goodness-of-fit index =.98; adjusted goodness-of-fit index =.95), test-retest (values from.83 to.91) and inter-and intrarater reliability were found. Concurrent validity between TGMD-2 and Movement Assessment Battery for Children was weak. The TGMD-2 is a validity and reliability instrument for Brazilian children. © 2012 Taylor and Francis Group, LLC.

Giugliani R.,Federal University of Rio Grande do Sul | Giugliani R.,Collaborating Center for the Development of Medical Genetic Services in Latin America | Giugliani R.,Instituto Nacional Of Genetica Medica Populacional Inagemp
Journal of Inherited Metabolic Disease | Year: 2012

The aim of newborn screening (NBS) programs is to detect a condition in a presymptomatic baby and provide management measures which could significantly improve the natural history of the disease. NBS programs for metabolic diseases were first introduced in North America and Europe and in the 1960s for phenylketonuria, expanded a few years later to include congenital hypothyroidism, and have been growing steadily in terms of number of conditions tested for and number of countries and births covered. Lysosomal storage diseases (LSDs) are a group of around 50 genetic conditions in which a defect in a lysosomal function occurs. LSDs are progressive conditions, being usually asymptomatic at birth, but with clinical features becoming apparent in childhood, with severe manifestations in most instances, high morbidity and shortened life span. Although individually rare, the prevalence of LSDs is significant when the group is considered as a whole (around 1:4,000-1:9,000 live births). Several management techniques, including bone marrow transplantation, enzyme replacement therapy, substrate inhibition therapy, pharmacological chaperones and many other approaches are transforming the LSDs into treatable conditions. However, lack of awareness and lack of access to tests cause a significant delay between onset of symptoms and diagnosis. Several lines of evidence showing that the earlier introduction of therapy may provide a better outcome, are bringing support to the idea of including LSDs in NBS programs. Due to advances in technology, high-throughput multiplex methods are now available for mass screening of several LSDs. Pilot projects were already developed in many countries for some LSDs, with interesting results. Although some NBS in Latin America has been carried out since the 1970s, it has so far been incorporated as a public health program in only a few countries in the region. It will probably take many years before NBS is implemented in most Latin American countries with a comprehensive coverage in terms of number of diseases and number of births. Population medical genetics is the area of medical genetics that aims at the study and medical care of the population, and not of the family, which is the case for clinical or medical genetics itself. It combines different aspects of genetics: clinical genetics; human population genetics, which investigates populations according to micro-evolutionary parameters; epidemiological genetics, traditionally involved in the study of common chronic diseases of polygenic etiology, except for Mendelian diseases; and sanitary or community genetics, which stands at the interface with public health, giving support to preventive health measures. Taking into account that several LSDs were identified in a higher frequency in selected areas and/or populations, the population medical genetics approach could help to introduce the NBS for LSDs in the region, with identification of areas with higher risk for selected diseases and design of customized screening program to address specific needs. As an example of the potential of this approach, a pilot program of NBS for MPS VI was implemented in a community from North East Brazil where 13 cases of MPS VI were identified in an area with 50,000 inhabitants. This program, which will enable not only identification and early treatment of affected newborns but also carrier detection, and which would allow genetic counseling for at-risk couples, could be an alternative model for a customized NBS of LSDs to be carried out in selected regions. © SSIEM and Springer 2011.

Zavascki A.P.,Federal University of Rio Grande do Sul
Expert Review of Anti-Infective Therapy | Year: 2014

The initial use of polymyxins, polymyxin B and colistin (administered as a pro-drug colistin methanesulfonate sodium [CMS]), mostly relied on old pharmacokinetic (PK) studies that lacked appropriate methodology. In recent years, many PK studies in both animals and humans have provided more consistent evidence supporting better use of these invaluable antibiotics. However, translating preclinical data to clinical practice is not always an easy task and some may experience difficulties on how recent knowledge on polymyxins can be applied into the patients' care. Although many questions are still unresolved, there are consistent data able to improve clinical practice when prescribing initial and maintenance doses of both polymyxin B and CMS. Considering the importance of optimal use of polymyxins, this editorial discusses recent PK findings and how to take advantage of them at the bedside to improve the treatment of patient with extensively-drug-resistant Gram-negative bacterial infections. © 2014 Informa UK, Ltd.

Hoppen C.,Federal University of Rio Grande do Sul | Kohayakawa Y.,University of Sao Paulo | Lefmann H.,TU Chemnitz
European Journal of Combinatorics | Year: 2012

For fixed positive integers r, k and ℓ with 1 ≤ ℓ < r and an r-uniform hypergraph H, let κ (H, k, ℓ) denote the number of k-colorings of the set of hyperedges of H for which any two hyperedges in the same color class intersect in at least ℓ elements. Consider the function KC(n,r,k,ℓ)=maxH∈Hnκ(H,k,ℓ), where the maximum runs over the family Hn of all r-uniform hypergraphs on n vertices. In this paper, we determine the asymptotic behavior of the function KC. (n, r, k, ℓ) for every fixed r, k and ℓ and describe the extremal hypergraphs. This variant of a problem of Erdo s and Rothschild, who considered edge colorings of graphs without a monochromatic triangle, is related to the Erdo s-Ko-Rado Theorem (Erdo s etal., 1961. [8]) on intersecting systems of sets. © 2011 Elsevier Ltd.

Vieira S.L.,Federal University of Rio Grande do Sul | Angel C.R.,University of Maryland University College
Journal of Applied Poultry Research | Year: 2012

Broiler responses of economic interest, such as BW gain, FCR, and breast meat yield (BMY), can be optimized by increasing amino acid (AA) concentrations, improving the AA balance, or both. The AA requirements to maximize a response are lowest for BW gain, increased for FCR, and highest for BMY. A maximum performance response is reached when the response plateaus, whereas an optimal response is the one providing the highest return per input. These are usually not the same. Strategies used in linear feed formulation differ in how dietary AA are included in the diet; therefore, understanding how these strategies affect broiler responses is necessary to compare ultimate potential benefits. Minimum CP restrictions are still used even when TSAA, Lys, and Thr restrictions are set simultaneously, and AA requirements are presently expressed as either total or digestible. The use of ratios of essential AA to Lys is more popular now that synthetic Thr has become commercially available, and it will likely have an increase in use when L-valine and L-isoleucine have competitive prices. The presentday high-yield broiler has an increased responsiveness to AA density, especially for Lys, which contrasts with published requirements still in use. Increasing Lys and other AA at the beginning of the bird's life has been shown to have some positive carryover effects on performance in later periods; however, increasing the Lys and essential AA in broiler diets in the last phases of production allows compensation for BMY because of the continuous high allometric growth rate of breast muscle. Gains in performance are expected to result from increases in dietary AA density; however, the decision regarding what AA density to use will depend on the cost of feed relative to the market price of meat. © 2012 Poultry Science Association, Inc.

Beggio P.C.,Federal University of Rio Grande do Sul | Beggio P.C.,State University of Norte Fluminense
Nuclear Physics A | Year: 2013

We study the factorial moments (Fq), the factorial cumulants (Kq) and the ratio of Kq to Fq (Hq = Kq/Fq) in pp/pp̄ collisions using an updated approach, in which the multiplicity distribution is related to the eikonal function. The QCD inspired eikonal model adopted contains contributions of quark-quark, quark-gluon and gluon-gluon interactions. Our work shows that the approach can reproduce the collision energy dependence of the Fq moments, correctly predicts that the first minimum of the Hq lies around q = 5 and qualitatively reproduces the oscillations of the Hq moments, as shown in the experimental data and predicted by QCD at preasymptotic energy. The result of this study seems to indicate that the Hq oscillations are manifestations of semihard component in the multiparticle production process. Predictions for multiplicity distribution and Hq moments at the LHC energy of s=14 TeV are presented. © 2013 Elsevier B.V..

This article approaches the use of qualitative methods in health research. Following the concept of "somatic modes of attention" and examples of previous ethnographic research, I discuss the dichotomies theory-methodology, subject-object, rationale-techniques to suggest that they may be responsible for what has been pointed out as important constraints of qualitative research: (1) the problem of choosing the right research techniques; (2) the dilemma of the number of cases to be studied; (3) the role of the context; and (4) data analysis/interpretation procedures. I argue that these separations can affect research ethics. Ethics needs to be incorporated in methodology as a whole and inform the choice of techniques, sampling procedures, the context and data analysis/interpretation. Finally, this paper points out that the specificity of qualitative research needs to be acknowledged by Research Ethics Committees and suggests they should look, more than anything, at each project's methodological adequacy together with ethical procedures.

Saurin T.A.,Federal University of Rio Grande do Sul
Science and Engineering Ethics | Year: 2015

While ethics in publishing has been increasingly debated, there seems to be a lack of a theoretical framework for making sense of existing rules of behavior as well as for designing, managing and enforcing such rules. This letter argues that systems-oriented disciplines, such as complexity science and human factors, offer insights into new ways of dealing with ethics in publishing. Some examples of insights are presented. Also, a call is made for empirical studies that unveil the context and details of both retracted papers and the process of writing and publishing academic papers. This is expected to shed light on the complexity of the publication system as well as to support the development of a just culture, in which all participants are accountable. © 2015 Springer Science+Business Media Dordrecht

Eliasson B.,University of Strathclyde | Haas F.,Federal University of Rio Grande do Sul
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2014

The influence of localized water currents on the nonlinear dynamics and stability of large amplitude, statistically distributed gravity waves is investigated theoretically and numerically by means of an evolution equation for a Wigner function governing the spectrum of waves. It is shown that water waves propagating in the opposite direction of a localized current channel can be trapped in the channel, which can lead to the amplification of the wave intensity. Under certain conditions the wave intensity can be further localized due to a self-focusing (Benjamin-Feir) instability. The localized amplification of the wave intensity may increase the probability of extreme events in the form of freak waves, which have been observed in connection with ocean currents. © 2014 American Physical Society.

Rodrigues C.D.S.,Federal University of Santa Catarina | Witt R.R.,Federal University of Rio Grande do Sul
Journal of Continuing Education in Nursing | Year: 2013

Background: Preceptorship is an emerging component of the Brazilian health care system for human resources education. This study attempted to identify competencies for preceptorship in this system. Methods: An exploratory descriptive study was conducted with the Delphi technique. The participants were primary health care professionals from the South of Brazil who were working in nine professional areas, including nursing. The participants had served as preceptors in an educational program promoted by the Ministries of Education and Health. Results: Forty-three competencies were identified and classified into nine domains: education, professional values, basic public health sciences, management, health care, teamwork, communication, community orientation, and professional development. Conclusion: The findings showed that preceptors were committed to the education of future health care professionals. The development of pedagogical skills was emphasized, as was the necessity of education before preceptorship. These competencies constitute a useful reference for continuing professional education. © SLACK Incorporated.

Sanchez-Pacheco S.J.,Federal University of Rio Grande do Sul
Herpetologica | Year: 2010

I describe a new species of Riama from the Pacific versant of the Andes in extreme southwestern Colombia. Among the species of Riama, the new species most resembles R. vieta, with which it shares rugose dorsal and ventral scales. Unlike R. vieta, the new species has three postoculars and males lack heavy black spots dorsally and black bands ventrally. Males of the new species have seven to eight femoral pores per leg (total number 1415) and two scales between the femoral pores (anterior cloacal plate scales paired). © 2010 by The Herpetologists' League, Inc.

Sanchez-Pacheco S.J.,Federal University of Rio Grande do Sul
Papeis Avulsos de Zoologia | Year: 2010

The poorly known Riama columbiana, Andean gymnophthalmid lizard from Colombia, is redescribed on the basis of syntypes and additional material. A lectotype is designated, its likely provenience is discussed, and its distribution and natural history are given.

Bertaco V.A.,Federal University of Rio Grande do Sul | de Lucena C.A.S.,Grande Rio University
Neotropical Ichthyology | Year: 2010

Astyanax obscurus and A. laticeps are redescribed. Both species were originally described from the laguna dos Patos system, Rio Grande do Sul, Brazil. The deepest and most robust body area close to the middle of the pectoral fins length, robust head, snout short and abrupt, body depth smaller than 41% of SL, reduced number of branched anal-fin rays, presence of one or two humeral spots, and a dark midlateral body stripe extending to the tip of the middle caudal-fin rays include both in the A. scabripinnis species complex. The presence of two humeral spots (vs. one), external row of the premaxillary with pentacuspid teeth (vs. tricuspid), and absence of bony hooks in all fins in males (vs. presence in anal and ventral fins) distinguish A. obscurus from A. laticeps. These species distinguish from species of this complex by meristic and morphometric characters and color pattern. An identification key for the species of genus occurring in the laguna dos Patos system is presented. © 2010 Sociedade Brasileira de Ictiologia.

Simionovski A.,National Center for Advanced Electronic Technology Microelectronics | Wirth G.,Federal University of Rio Grande do Sul
IEEE Transactions on Device and Materials Reliability | Year: 2014

This paper describes the design, the physical implementation, and the test procedure for a complementary pair of bulk built-in current sensors (Bulk-BICS) circuits, intended to detect single-event transients (SETs) induced by ionizing radiation on n- and p-type metal-oxide-semiconductor transistors. Electrical characterization of the prototype chip was performed, and the results are presented here. While not subjected to actual ionizing radiation, the performance of the manufactured integrated circuit is evaluated from its response to electrical test signals. © 2001-2011 IEEE.

Determination of polymyxin susceptibility profile is important to monitor resistance rates and for implementing control measures for polymyxin-resistant carbapenem-resistant Enterobacteriaceae. Some laboratorial methods have been used to determine the polymyxin susceptibility profile. However, the performance of MicroScan WalkAway has been poorly reported for KPC-producing Klebsiella pneumoniae, so far. To evaluate two different methods, Etest and the MicroScan automated system, in determining minimal inhibitory concentration (MIC) of polymyxin among KPC-producing K. pneumoniae isolated from patients in two care units (ICUs) of a tertiary hospital in Porto Alegre, Southern Brazil. A total of 101 KPC-Kb isolates were obtained from rectal swabs and clinical specimens (urine, blood, and endotracheal aspirate). Colistin and polymyxin B MICs were determined using MicroScan WalkAway automated system and Etest, respectively. Discrepant results were resolved by broth microdilution (BMD). MicroScan showed 88.1% of sensitivity for predicting polymyxin B resistance in KPC-producing K. pneumoniae compared to the results obtained by Etest. All discrepant results were tested by BMD and these were concordant with results obtained by Etest. The MicroScan automated system does not seem to be very efficient for the screening of polymyxin-resistant isolates once an inappropriate sensitivity is achieved. The results presented here show the need for confirmation of the susceptibility profile by use of a dilution method (Etest or BMD). © 2015 APMIS Published by John Wiley & Sons Ltd.

Bittencourt E.,Federal University of Rio Grande do Sul
International Journal of Plasticity | Year: 2014

Dynamic terms are included in the balance equations that govern a higher-order crystal plasticity formulation. The resulting equations are integrated in time by the central-difference explicit method. The methodology avoids solution methods based on the inversion of the associated stiffness matrices. This is a great advantage of the proposed methodology, considering that these matrices tend to be highly ill-conditioned. As the solution becomes dependent on the time-step size used in the integration, a stability study is presented. Only a rate independent constitutive law is taken into account. As examples, a crystal layer and a composite material under simple shear and the wedge indentation of a single crystal are considered. Comparisons with an implicit quasi-static solution method show the robustness of the proposed methodology, but reveal an elevated computational cost related to it. © 2013 Elsevier Ltd. All rights reserved.

Fischer G.,University of Verona | Figueiredo P.,Federal University of Rio Grande do Sul | Ardigo L.P.,University of Verona
International Journal of Sports Physiology and Performance | Year: 2015

Purpose: To investigate physiological performance determinants of the partial laps and an overall 22-km handbiking (HB) time trial in athletes with high paraplegia. Methods: Seven Male HB athletes with spinal cord injury (lesion levels thoracic 2-8) performed a laboratory maximal incremental test under cardiorespiratory-mechanical monitoring including respiratory-exchange ratio (RER), oxygen uptake (V·O2), and mechanical power output (PO). Individual first and second ventilatory thresholds (V·O2VT1 and V·O2VT2), V·O2peak, and POpeak were posteriorly identified. Athletes also performed a simulated HB time trial along a 4-lap bike circuit under cardiorespiratory measurement. Overall metabolic cost (C) and %V·O2peak (ratio of V·O2 to V·O2peak) were calculated from race data. Race performance was defined as mean race velocity (v). Results: athletes completed the 22-km HB time trial in 45 ± 6 min, at 29.9 ± 3.6 km/h, with %V·O2peak = 0.86 ± 0.10 and RER = 1.07 ± 0.17. V·O2peak (r = .89, P = .01), POpeak (r = .85, P = .02), V·O2VT1 (r = .96, P = .001), V·O2VT2 (r = .92, P = .003), and C (2nd lap, r = .78; 3rd lap, r = .80; and 4th lap, r = .80) were significantly (P < .05) positively correlated with race performance. Within-subjects correlation coefficient revealed a large and significant (r = .68, P < .001) relationship between %V·O2peak and v. Conclusions: V·O2peak, POpeak, ventilatory thresholds, %V·O2peak, and C appeared to be important physiological performance determinants of HB time trial. © 2015 Human Kinetics, Inc.

Portella A.K.,Hospital da Crianca Santo Antonio | Silveira P.P.,Federal University of Rio Grande do Sul
Annals of the New York Academy of Sciences | Year: 2014

Fetal growth restriction results from a failure to achieve a higher growth potential and has been associated with many maternal conditions, such as chronic diseases (infections, hypertension, and some cases of diabetes and obesity), exposures (tobacco smoke, drugs), and malnutrition. This early adversity induces a series of adaptive physiological responses aimed at improving survival, but imposing increased risk for developing chronic nontransmittable diseases (obesity, type II diabetes, cardiovascular disease) in the long term. Recently, mounting evidence has shown that fetal growth impairment is related to altered feeding behavior and preferences through the life course. When living in countries undergoing nutritional transition, in which individuals experience the coexistence of underweight and overweight problems (the "double burden of malnutrition"), fetal growth-restricted children can be simultaneously growth restricted and overweight-a double burden of malnutrition at the individual level. Considering food preferences as an important aspect of nutrition security, we will summarize the putative neurobiological mechanisms at the core of the relationship between fetal growth and nutrition security over the life course and the evidence linking early life adversity to later food preferences. © 2014 New York Academy of Sciences.

Wang Z.,Nankai University | Wang Z.,Hong Kong Baptist University | Weng Z.,Dalian University of Technology | Zhu X.,Dalian University of Technology | Arenzon J.J.,Federal University of Rio Grande do Sul
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2012

We study the evolution of cooperation in evolutionary spatial games when the payoff correlates with the increasing age of players (the level of correlation is set through a single parameter, α). The demographic heterogeneous age distribution, directly affecting the outcome of the game, is thus shown to be responsible for enhancing the cooperative behavior in the population. In particular, moderate values of α allow cooperators not only to survive but to outcompete defectors, even when the temptation to defect is large and the ageless, standard α=0 model does not sustain cooperation. The interplay between age structure and noise is also considered, and we obtain the conditions for optimal levels of cooperation. © 2012 American Physical Society.

Machado I.G.,Federal University of Rio Grande do Sul
Soldagem e Inspecao | Year: 2011

The main aim of this work, is to show for the welding engineers and/or designers of welded structures, the many existing options in the design of fillet welded joints, when loaded transverse, inclined, or parallel to the axis of the weld bead. This is done through a discussion on the very fundamental aspects of this kind of joint, a series of equations (from standards or Code) that allow the throat dimensioning, and examples using actual base metals and consumables. It is also a purpose of this paper to caution those professionals, for each one of the standards (such as AISC and Eurocode 3), or Codes (such as AWS), or even authoritative organizations (such as IIW), have specific characteristics (or "philosophies"), some of them very distinct. Finally, but not less important, this paper closes analysing fillet welded joints under concepts of the theory of elasticity and local plasticity.

Lorenzini G.,University of Parma | Corra R.L.,Grande Rio University | Domingues Dos Santos E.,Grande Rio University | Rocha L.A.O.,Federal University of Rio Grande do Sul
Journal of Heat Transfer | Year: 2011

Constructal design is a method that conducts the designer toward flow (e.g., heat flux) architectures that have greater global performance. This numerical work uses this method to seek for the best geometry of a complex assembly of fins, i.e., an assembly where there is a cavity between the two branches of the T-Y-assembly of fins and two additional extended surfaces. The global thermal resistance of the assembly is minimized four times by geometric optimization subject to the following constraints: the total volume, the volume of fin material, the volume of the cavity, and the volume of the two additional extended surfaces. Larger amount of fin material improves the performance of the assembly of fins. The three times optimized global thermal resistance of the complex assembly of fins performs 32% better than the best T-Y-configuration under the same thermal and geometric conditions. The three times minimized global thermal resistance of the complex assembly of fins was correlated by power laws as a function of its corresponding optimal configurations. © 2011 American Society of Mechanical Engineers.

Wallau G.L.,Federal University of Santa Maria | Ortiz M.F.,Federal University of Rio Grande do Sul | Loreto E.L.S.,Federal University of Santa Maria
Genome Biology and Evolution | Year: 2012

The genetic similarity observed among species is normally attributed to the existence of a common ancestor. However, a growing body of evidence suggests that the exchange of genetic material is not limited to the transfer from parent to offspring but can also occur through horizontal transfer (HT). Transposable elements (TEs) are DNA fragments with an innate propensity for HT; they are mobile and possess parasitic characteristics that allow them to exist and proliferate within host genomes. However, horizontal transposon transfer (HTT) is not easily detected, primarily because the complex TE life cycle can generate phylogenetic patterns similar to those expected for HTT events. The increasingly large number of new genome projects, in all branches of life, has provided an unprecedented opportunity to evaluate the TE content and HTT events in these species, although a standardizedmethod of HTT detection is required before trends in the HTT rates can be evaluated in a wide range of eukaryotic taxa and predictions about these events can bemade. Thus,we propose a straightforward hypothesis test that can be used by TE specialists and nonspecialists alike to discriminate between HTT events and natural TE life cycle patterns.Wealso discuss several plausible explanations and predictions for the distribution and frequency of HTT and for the inherent biases of HTT detection. Finally, we discuss some of the methodological concerns for HTT detection that may result in the underestimation and overestimation of HTT rates during eukaryotic genome evolution. © 2012 The Author(s).

Kramer C.K.,University of California at San Diego | Kramer C.K.,Federal University of Rio Grande do Sul | Araneta M.R.G.,University of California at San Diego | Barrett-Connor E.,University of California at San Diego
Diabetes Care | Year: 2010

OBJECTIVE - To examine the sensitivity and specificity of A1C as a diagnostic test for type 2 diabetes in older adults. RESEARCH DESIGN AND METHODS - Cross-sectional study of communitydwelling adults without known diabetes who had an oral glucose tolerance test and A1C measured on the same day. RESULTS - Mean age of the 2,107 participants was 69.4 ± 11.1 years; 43% were men. Based on the American Diabetes Association (ADA) criteria, 198 had previously undiagnosed type 2 diabetes. The sensitivity/specificity of A1C cut point of 6.5% was 44/79%. Results were similar in age- and sex-stratified analyses. Given the A1C cut point of 6.5%, 85% of participants were classified as nondiabetic by ADA criteria. CONCLUSIONS - The limited sensitivity of the A1C test may result in delayed diagnosis of type 2 diabetes, while the strict use of ADA criteria may fail to identify a high proportion of individuals with diabetes by A1C ≥6.5% or retinopathy. © 2010 by the American Diabetes Association.

Rio Grande do Sul is the southernmost state of Brazil with peculiar flora and fauna associated to the morfoclimatic characteristics of the region. The diversity of Testudines from Rio Grande do Sul is represented by six freshwater turtle species and five sea turtle species. This study reports on the freshwater turtle diversity of Rio Grande do Sul, based on a compilation of published and some new data on their biology and conservation status.

Da Silva A.P.,Federal University of Rio Grande do Sul | Lubianca Neto J.F.,Federal University of Health Sciences, Porto Alegre | Santoro P.P.,University of Sao Paulo
Otolaryngology - Head and Neck Surgery | Year: 2010

Objective: To compare videofluoroscopy swallowing study (VFSS) with the fiberoptic endoscopic evaluation of swallowing (FEES) in children and to determine the accuracy of FEES in the diagnosis of specific swallowing disorders. Study Design: Cross-sectional study. Setting: Hospital da Criança Santo Antônio, affiliated with Santa Casa de Misericórdia Hospital Complex, Porto Alegre, RS, Brazil. Subjects and Methods: FEES findings were compared to those of VFSS in 30 children. Kappa coefficients for interobserver agreement were calculated. Thereafter, these coefficients were evaluated in terms of agreement between FEES and VFSS. In addition, the sensitivity, specificity, positive predictive value, and negative predictive value of FEES were calculated for four swallowing parameters (posterior spillover, pharyngeal residues, laryngeal penetration, and laryngotracheal aspiration). Results: Interobserver agreement rates greater than 70 percent were obtained for all FEES parameters analyzed, except for pharyngeal residues with puree consistency (agreement = 66.7%, κ = 0.296, P = 0.091). Laryngeal aspiration and penetration yielded the best level of agreement (100%, κ = 1) for the laryngeal aspiration of puree residues. Conclusion: The diagnostic agreement between FEES (both observers) and VFSS was low. Regarding the analyzed parameters, laryngeal penetration and aspiration yielded the highest interobserver agreement in terms of FEES, and also showed the highest specificity and positive predictive value when compared to VFSS. © 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation.

In this study, the main aspects found in the literature about refractories corrosion were reviewed, evaluating the feasibility of certain tests and relating them with experimental results. In the first part of this work, the main properties of the microstructure of the refractories were discussed, such as aggregates and the matrix, including the binder phase (resins or pitch), presence of carbon, porosity, additives and anti-oxidants. In this second part, the remaining aspects of corrosion, such as physical and chemical properties of refractories, slag characteristics and operating conditions are discussed, linking the theory with data from industrial practice. Specifically, it was analyzed the refractory from slag-line of steel ladle.

Layton W.,University of Pittsburgh | Manica C.C.,Federal University of Rio Grande do Sul | Neda M.,University of Nevada, Las Vegas | Rebholz L.G.,Clemson University
Computer Methods in Applied Mechanics and Engineering | Year: 2010

We study stability, accuracy and efficiency of algorithms for a new regularization of the NSE, the NS-over(ω, ̄) model (in which the vorticity term, over(ω, ̄) = ∇ × over(u, ̄), is averaged) given by. ut - u × (∇ × over(u, ̄)) + ∇ q - ν Δ u = f, ∇ · u = 0 . This is similar to the NS-α model (in which the nonlinear term is over(u, ̄) × (∇ × u)), but the small difference opens attractive algorithmic possibilities. We give tests both confirming the predicted rates of convergence and exhibiting some shared limitations of both models. The experiments also show the discrete NS-over(ω, ̄) simulation has greater accuracy (Tables 3 and 4) at less cost (Table 2) and requires significantly fewer degrees of freedom (Section 1.1) than a comparable NS-α simulation. The experiments suggest consideration of adding grad-div stabilization and higher accuracy NS-over(ω, ̄)-deconvolution models as a next logical step. In fact, this combination produced accurate results (see Figs. 10 and 11) on the coarsest mesh (mesh 1) upon which all other methods, models and variants tested failed. © 2009 Elsevier B.V. All rights reserved.

Coutinho D.F.,Pontifical Catholic University of Rio Grande do Sul | Da Silva Jr. G.J.M.,Federal University of Rio Grande do Sul
IET Control Theory and Applications | Year: 2010

This study focuses on the problem of regional stability analysis of rational control systems with saturating actuators. Estimates of the region of attraction are computed by means of invariant domains associated to rational Lyapunov functions. Conditions for computing these invariant domains (regions of stability) are proposed in the form of linear matrix inequalities (LMIs). These conditions are derived considering a differential-algebraic representation of the rational system dynamics. The saturation effects are taken into account by means of a generalised sector condition for deadzone non-linearities. The obtained conditions are cast in convex optimisation schemes in order to compute a Lyapunov function which leads to a maximised estimate of the region of attraction. © 2010 The Institution of Engineering and Technology.

The scope of this article is to reflect upon the medicalization of male sexuality basedon the counterpoint between two distinct historical processes. The first of these is the major trend towards intervention in male sexuality which occurred in the early twentieth century in Brazil as a result of syphilis and the broader campaign against venereal disease. The second concerns the medicalization of sexuality through the focus on erectile dysfunction and the creation of a new pharmacology of sex which has become inevitable with the transition to the twenty-first century. This contrast enables us to see some important differences. The study highlights the new emphasis on the notion of sexual health based on individual improvement and use of medications. It also demonstrates that the promotion of male interest in sexual performance serves as a gateway to approach the treatment of male health.

In this study, main aspects found in the literature about refractories corrosion were reviewed, evaluating the feasibility of certain tests and relating them with experimental results. The main cause of refractories wear is considered the chemical attack that the material suffers, but it is also infuenced by thermal and mechanical factors, often concomitantly. Increased life of refractories faces the understanding of complex phenomena and depends on operational factors, whose control is diffcult in routine steel company processing. In addition the physical and chemical properties of refractories must be considered. In the proposed approach, research data of corrosive wear of basic refractories, including microstructural analysis, are related to the theoretical fundamentals found in literature.

Nagabhushana G.P.,Bangalore University | Nagaraju G.,Federal University of Rio Grande do Sul | Chandrappa G.T.,Bangalore University
Journal of Materials Chemistry A | Year: 2013

A nanocrystalline m-BiVO4 photocatalyst for H2 evolution, which works under UV-light irradiation, has been synthesized by a facile solution combustion synthesis method. Hydrogen evolution over BiVO 4 is a significant result in the field of renewable energy sources and here we are the first to show hydrogen evolution experimentally with BiVO4 in the absence of either coupling oxides or doping metals. The yield of hydrogen generated is about 489 μmol per 2.5 h of reaction under UV irradiation. The ultra-light yellow crystalline combustion derived nanopowder exhibits porous morphology with a strong absorption in the visible light region. The estimated band gap of BiVO4 powder is about 2.52 eV. The powder shows highly visible photocatalytic activity towards methylene blue degradation under sun light irradiation. The H2 evolution and photocatalytic activity of BiVO4 nanocrystalline powder can be attributed to its physical properties such as nanosize particles and large surface area. © 2013 The Royal Society of Chemistry.

Ottoni G.L.,Federal University of Rio Grande do Sul | Lorenzi T.M.,Pontifical Catholic University of Rio Grande do Sul | Lara D.R.,Pontifical Catholic University of Rio Grande do Sul
Journal of Affective Disorders | Year: 2011

Background: Emotional and cognitive functioning have been involved in insomnia etiology, and sleep disturbances are closely related to psychiatric disorders and personality traits. This study investigates the association of temperament with subjective sleep parameters. Methods: In this web-survey, 5129 subjects (25.3% males) completed the Combined Emotional and Affective Temperament Scale (CEATS), which assesses emotional (fear, anger, drive and control) and affective (e.g. cyclothymic, hyperthymic) temperaments. Subjects also answered questions regarding subjective sleep parameters, psychiatric diagnosis, psychotropic medication intake and cigarette smoking. Results: As control scores decreased, the later were the bed and the wake up time. Total sleep time was weakly associated with emotional temperaments. The higher the score of anger and the lower the score of control, the higher was the sleep-onset latency. As the anger score increased and the drive, fear and control scores decreased, the higher the number of nightly awakenings. The higher the drive and the control and the lower the anger scores, the better the sleep quality. For affective temperaments, depressives, labiles (related to ADHD) and cyclothymics (related to bipolar II disorders) go to bed and wake up later and have a worse profile regarding other sleep parameters. Hyperthymics and euthymics showed favorable sleep profiles. Limitations: Sample included a sign