Santa Maria, Brazil
Santa Maria, Brazil

The Universidade Federal de Santa Maria is a Brazilian public university located in Santa Maria, in the state of Rio Grande do Sul, funded by the federal government of Brazil. It was founded in 1960, by Professor José Mariano da Rocha Filho.UFSM's presence in the municipality of Santa Maria is one of the reasons why the city is sometimes called "university city" or "culture city". Santa Maria is located in western Rio Grande do Sul, approximately 290 km far from the capital city of the state, Porto Alegre. Set in the heart of the pampas of Brazil, the city thrives with gaúcho culture.UFSM is a public, free university, and students do not pay any tuition fees. It is the oldest federal university not located in a Brazilian state capital city, and the largest in number of undergraduate courses offered in Rio Grande do Sul state. Wikipedia.

Time filter

Source Type

Sellaoui L.,University of Monastir | Lima E.C.,Federal University of Rio Grande do Sul | Dotto G.L.,Federal University of Santa Maria | Lamine A.B.,University of Monastir
Journal of Molecular Liquids | Year: 2017

Two activated carbons were modified with iron benzoate and cobalt (MAC-1), and with iron oxalate and cobalt (MAC-2) to study the adsorption process of two pharmaceutical molecules named amoxicillin (AMX) and paracetamol (PCT). For this objective, a network of adsorption isotherms was well recorded at different temperatures ranged from 25 to 50 °C. New explanations were deduced by application the double layer model with two adsorption energies on adsorption isotherms formulated by the statistical physics approach. By investigation the number of adsorbed molecules per site, a lateral interaction between the (AMX) and (PCT) pharmaceutical molecules and modified activated carbons was successfully described. In addition to this, an aggregation phenomenon of AMX and PCT was studied and interpreted. When the adsorption saturation is reached; an adsorbed quantity was calculated and interpreted of each pharmaceutical molecule on both adsorbents indicating that the MAC-2 adsorbent could present higher efficiency for wastewater treatment. Thermodynamically, the positional entropy was treated giving a good explanation of AMX and PCT pharmaceutical molecules arrangement on modified activated carbons during the adsorption period. © 2017 Elsevier B.V.

Mancuso M.,Federal University of Santa Maria | Carol E.,National University of La Plata | Kruse E.,National University of La Plata | Mendes Rodrigues F.,Rede Ferroviaria Nacional REFER
Hydrology Research | Year: 2017

The variability in dynamics and salinity of the coastal alluvial aquifer on which the city of Lisbon is located was evaluated. The evaluation was based on the analysis of level and groundwater electrical conductivity fluctuations depending on the tide in the Tagus River. The results obtained made it possible to recognize three sectors. First, a littoral sector where the variations in level and salinity are larger on the coast and decrease towards the innermost sections of the alluvial fan. Second, a sector close to the docks where there is greater dynamic and salinity variability than in the coastal sectors, as the excavations of the docks favour the tidal propagation towards the aquifer. And third, a sector located towards the apex of the alluvial fan associated with the dynamics of the stormwater channel. In this sector, the largest periodical water table fluctuations in the aquifer occur, since the freshwater that cannot drain towards the river enters the aquifer at high tide, causing a slight decrease in salinity content. On the basis of these results, conceptual models of hydrogeological behaviour were used to describe the spatial and temporal variations in the hydrodynamic and salinity characteristics of groundwater. © IWA Publishing 2017.

Nicolini A.,Federal University of Santa Maria | Carnielutti F.,Federal University of Santa Maria | Pinheiro H.,Federal University of Santa Maria | Ricciotti A.,Federal University of Rondônia
ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings | Year: 2016

This paper presents a discrete time controller for the circulating current of three-phase voltage fed converters with two magnetically coupled legs that uses carried-based discontinuous modulation. The discontinuous modulation produces multilevel equivalent PWM line-to-line output voltages with reduced harmonic distortion and equally distributes the commutations between the switches. A state machine is used to reduce the number of commutations. Using this state machine a non-linear controller is proposed to keep the circulating current close to zero. Moreover, it is important to mention that the implementation of the proposed modulation and controller are straightforward, requiring neither a complex hardware nor a high development effort. Furthermore, simulation and experimental results are presented to demonstrate the good performance of the proposed method. © 2016 IEEE.

Breunig F.M.,Federal University of Santa Maria | Pereira Filho W.,Federal University of Santa Maria | Galvao L.S.,National Institute for Space Research | Wachholz F.,University of the State of Amazonas | Cardoso M.A.G.,National Institute for Space Research
Science of the Total Environment | Year: 2017

Reservoirs are important in Brazil for the production of hydroelectric power and human water consumption. The objective was to evaluate the variability of total suspended solids (TSS) and chlorophyll-a as well as the rainfall/temperature and land use impacts on these optically active constituents (OAC). The study area is the Passo Real reservoir in south Brazil. The methodology was divided in four steps. First, we used wavelet to detect anomalous periods of rainfall and temperature (2002–2014). Second, we carried out 12 field campaigns to obtain in situ measurements for limnological characterization (2009–2010). The third step was the analysis of Moderate Resolution Imaging Spectroradiometer (MODIS)/Terra and Aqua satellites data corrected and non-corrected for bidirectional effects. Finally, we evaluated potential drivers of OAC changes over time using cross-correlation analysis. The results showed a decrease in the TSS and chlorophyll-a concentrations from the upper to the lower streams of the reservoir. The exponential regression between the MODIS red reflectance and TSS had an adjusted r2 of 0.63. It decreased to 0.53 for the relationship between the green reflectance and chlorophyll-a. MODIS data corrected for bidirectional effects provided better OAC estimates than non-corrected data. The validation of MODIS TSS and chlorophyll-a estimates using a separate set of measurements showed a RMSE of 2.98 mg/l and 2.33 μg/l, respectively. MODIS estimates indicated a gradual transition in OAC from the upper to the lower streams in agreement with the patterns observed using field limnological data. The analysis of land use (greenness) showed two well-defined crop cycles per year. The highest seasonal concentrations of TSS and chlorophyll-a were observed in December and the lowest concentrations in April. Despite the interrelationships between both factors, our cross-correlation analysis indicated that the great concentrations of TSS and chlorophyll-a were primarily controlled by rainfall and secondarily by land use. © 2016 Elsevier B.V.

da Silva F.D.,Federal University of Santa Maria | Simoes C.A.D.P.,Federal University of Santa Maria | dos Santos S.S.,Federal University of Santa Maria | Lang E.S.,Federal University of Santa Maria
Journal of Organometallic Chemistry | Year: 2017

In this article we describe the synthesis and structural characterization of a series of organyltellanyl(IV) trihalides containing the [2-((dimethylamino)methyl)phenyl] moiety [2-(Me2NCH2)C6H4TeX3] (X = Cl, Br, I), and some of its derivatives in the form of rare zwitterionic compounds with organyltellanyl(II) groups. The supramolecular structure of the different organyltellanyl halides presents considerable changes due to the nature of Te⋯X and X⋯X secondary interactions. The positive and negative charges of the zwitterionic compounds, the size of the halogens and the repulsion of the lone electron pairs around the tellurium atom were also evaluated. All compounds were characterized by single crystal X-ray diffraction, vibrational spectroscopy (FT-IR and Raman) and NMR (1H and 125Te) spectroscopy and elemental analysis. © 2017 Elsevier B.V.

Irondi E.A.,Kwara State University | Agboola S.O.,University of Ibadan | Oboh G.,Federal University of Technology Akurre | Boligon A.A.,Federal University of Santa Maria
Journal of Intercultural Ethnopharmacology | Year: 2016

Aim: To evaluate the phenolics composition and inhibitory effect of the leaves extracts of Ocimum basilicum and Ocimum gratissimum on two key enzymes (pancreatic lipase [PL] and angiotensin 1-converting enzyme [ACE]) involved in obesity and hypertension in vitro. Materials and Methods: The phenolics (flavonoids and phenolic acids) were quantified using high-performance liquid chromatography coupled with diode array detection. PL and ACE inhibitory effects; DPPH* and ABTS*+ scavenging activities of the extracts were tested using spectrophotometric methods. Results: O. basilicum had the following major phenolics: Rutin, quercetin, and quercitrin (flavonoids); caffeic, chlorogenic, and gallic acids (phenolic acids); while O. gratissimum had the following major phenolics: Rutin, quercitrin, and luteolin (flavonoids); ellagic and chlorogenic acids (phenolic acids). “Extracts of both plants inhibited PL and ACE; scavenged DPPH* in a dose-dependent manner”. O. gratissimum extract was more potent in inhibiting PL (IC50: 20.69 μg/mL) and ACE (IC50: 29.44 μg/mL) than O. basilicum (IC50: 52.14 μg/mL and IC50: 64.99 μg/mL, against PL and ACE, respectively). O. gratissimum also scavenged DPPH* and ABTS*+ more than O. basilicum. Conclusion: O. basilicum and O. gratissimum leaves could be used as functional foods for the management of obesity and obesity-related hypertension. However, O. gratissimum may be more effective than O. basilicum. © SAGEYA.

Irondi E.A.,Kwara State University | Agboola S.O.,University of Ibadan | Oboh G.,Federal University of Technology Akurre | Boligon A.A.,Federal University of Santa Maria | And 2 more authors.
Journal of Intercultural Ethnopharmacology | Year: 2016

Background/Aim: Elevated uric acid level, an index of gout resulting from the over-activity of xanthine oxidase (XO), increases the risk of developing hypertension. However, research has shown that plant-derived inhibitors of XO and angiotensin 1-converting enzyme (ACE), two enzymes implicated in gout and hypertension, respectively, can prevent or ameliorate both diseases, without noticeable side effects. Hence, this study characterized the polyphenolics composition of guava leaves extract and evaluated its inhibitory effect on XO and ACE in vitro. Materials and Methods: The polyphenolics (flavonoids and phenolic acids) were characterized using high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD). The XO, ACE, and Fe2+-induced lipid peroxidation inhibitory activities, and free radicals (2,2-diphenylpicrylhydrazyl [DPPH]* and 2,2´-azino-bis-3-ethylbenzthiazoline-6-sulphonic [ABTS]*+) scavenging activities of the extract were determined using spectrophotometric methods. Flavonoids were present in the extract in the order of quercetin > kaempferol > catechin > quercitrin > rutin > luteolin > epicatechin; while phenolic acids were in the order of caffeic acid > chlorogenic acid > gallic acids. The extract effectively inhibited XO, ACE and Fe2+-induced lipid peroxidation in a dose-dependent manner; having half-maximal inhibitory concentrations (IC50) of 38.24 ± 2.32 μg/mL, 21.06 ± 2.04 μg/mL and 27.52 ± 1.72 μg/mL against XO, ACE and Fe2+-induced lipid peroxidation, respectively. The extract also strongly scavenged DPPH* and ABTS*+. Conclusion: Guava leaves extract could serve as functional food for managing gout and hypertension and attenuating the oxidative stress associated with both diseases. © SAGEYA.

Marangoni C.,Federal University of Santa Maria | Cichoski A.J.,Federal University of Santa Maria | Barin J.S.,Federal University of Santa Maria
International Food Research Journal | Year: 2017

It was held supplementation of olive leaves (OL) in the diet of Cobb's broiler of the 5 and 10 g of leaves per kg of feed and subsequently evaluated the physico-chemical and sensory characteristics of the meat of the thighs and drumsticks for 120 days under frozen storage at -18°C. The use of 5 g of OL reduced the TBARs value, peroxide value and carbonyl protein. The meat of chicken that had received OL largest CRA values and lower losses by exudation during storage. The thighs and drumsticks of treatments with OL, developed fewer taste and odor of rancid, and stood juicier and less acidic than the treatment he received traditional diet. These results suggest the use of OL on chicken diet in order to improve the oxidative stability, chemical physical and sensory frozen meat stored. © All Rights Reserved.

Soroldoni S.,Grande Rio University | Abreu F.,Grande Rio University | Castro I.B.,Federal University of São Paulo | Duarte F.A.,Federal University of Santa Maria | Pinho G.L.L.,Grande Rio University
Journal of Hazardous Materials | Year: 2017

Antifouling paint particles (APPs) are generated during periodical maintenance of boat hulls. Chemical composition and toxicity (either chronic or acute) of APPs found in the sediment was evaluated using the epibenthic copepod Nitokra sp. The APPs analyzed showed the presence of high levels of metals such as Cu (234,247 ± 268 μg g−1), Zn (112,404 ± 845 μg g−1) and the booster biocide DCOIT (0.13 μg g−1). Even at low concentrations (as from 5 mg g−1 of APPs by mass of sediment) a significantly decrease in the fecundity was observed in laboratory tests. When the sediment was disturbed in elutriate test, a LC50 of 0.14% for APPs was found. This study was the first assessment of toxicity associated with the presence of APPs in sediment to benthic organisms, and it calls attention to the need of improving regulations in boatyards and marina areas. © 2017 Elsevier B.V.

de Carvalho J.D.T.,Federal University of Santa Maria | Essi L.,Federal University of Santa Maria | de Oliveira J.M.S.,Federal University of Santa Maria
Acta Botanica Brasilica | Year: 2017

This paper presents a morphological analysis of the flower and floral trichomes of three rare species of Dyckia: Dyckia ibicuiensis, D. polyclada and D. racinae. Flowers at anthesis were collected from natural populations and subjected to morphometric and microscopic analysis. Among the most representative features for Dyckia are: morphometrics of individual floral parts; the general configuration of the androecium and gynoecium; the degree of fusion of the stigmatic lobes; the morphology of the ovules, especially in relation to the chalazal appendix; and the presence and constitution of peltate trichomes in the perianth, which exhibited a polymorphism not previously reported for Dyckia. The characters were effective at describing each species, proposing phylogenetic inferences and recognizing infrageneric groupings. We propose two species groups, which are consistent with previous hypotheses about the relationships among the species of the genus. The objective of this study was to provide floral morphological data useful for characterizing these three rare species, delimiting the genus and forming phylogenetic hypotheses. © 2017, Sociedade Botanica do Brasil. All rights reserved.

A same species can, under different environmental conditions, show variations in its growth trend and consequently in its final production. The dominant height (h100) is one of the most important variables for the forest growth and yield prediction, since we can see that a several number of yield functions are based on the dominant height description by site index equations. This paper had as objective to evaluate possible differences in the dominant height growth between two Eucalyptus saligna Smith clones and among different productivity soil classes, on which ones are implanted both Eucalyptus saligna clones. A set of permanent plots with annual or bi-annual measurements was used to fit different models of dominant height by age. Since the best model was defined and, utilizing the analysis of covariance, we tried to define the existence of different growth trends in dominant height. The growth trend analysis by using Backman’s function showed significant differences between both clones and among the different soil classes for clone 2864. Clone 4039 did not show a growth trend sharply different which would enough to separate this clone in two soil based groups. As a final result, we have that three different growth groups should be created to appropriately describe the dominant height growth: Group I-Clone 2864 and soil classes 1 and 2; Group II-Clone 2864 and soil classes 3, 4 and 5 and Group III-Clone 4039 and all soil classes. © 2017, Universidade Federal de Santa Maria. All rights reserved.

Severo F.F.,Federal University of Santa Maria | Aita N.T.,Federal University of Santa Maria | Marques L.G.,Federal University of Santa Maria | da Silva L.S.,Federal University of Santa Maria
Ciencia Rural | Year: 2017

It has become possible to evaluate the conversion of soil organic matter (SOM) in pastures and arboreal crops due to the difference between the photosynthetic cycles of Eucalyptus (C3) and most grasses (C4). The auto analyzer method coupled to the IRMS (Isotope Ratio Mass Spectrometer) in the present study evaluated the 13C content in soil profiles of Eucalyptus plantations of different ages (2, 10 and 21 years), in natural regeneration areas and natural grazing fields, and estimated the SOM conversion of each crop type of. The initial management of all sampled areas was natural pasture. The following profile layers were evaluated: 0-5, 5-10, 10-20, 20-30, 30-40, 40-50, 50-70 and 70-90cm, and the contribution of Eucalyptus biomass over the years of farming was estimated in the SOM conversion process. After 2 years of planting Eucalyptus, the beginning of pasture carbon conversion process occurred in the surface layer (0-5cm). Ten years after planting, the process of converting organic matter by arboreal crops reached the layers up to 20cm. After 21 years of planting and in natural regeneration areas, the entire profile has already been changed by planting Eucalyptus and native tree species. © 2017, Universidade Federal de Santa Maria. All rights reserved.

Salgado-Neto G.,Federal University of Santa Maria | Palma J.,Cooperativa Central Gaucha LTDA | Costa V.A.,Centro Experimental Central do Instituto Biologico
Ciencia Rural | Year: 2017

This note is the first report of Syntomopus parisii De Santis 1976 and Leptomeraporus sp. (Hymenoptera, Pteromalidae) simultaneously parasitizing Melanagromyza sojae Zehntner, 1900 (Diptera, Agromyzidae) in Brazil. The Pteromalidae parasitoids are natural enemies of stem miner flies, opening perspectives for biological control of soybean stem miner fly. © 2017, Universidade Federal de Santa Maria. All rights reserved.

Fernandes A.P.D.,Federal University of Paraná | Hoeflich V.A.,Federal University of Paraná | Luchesa C.J.,Centro Universitario Curitiba | De Farias J.A.,Federal University of Santa Maria
Ciencia Florestal | Year: 2017

This paper analyzed the evolution of the components costs of the plywood production and the prices paid to the industry and also identified the influence of macroeconomic variables in this evolution. The survey was conducted based on costs and prices between 2005 and 2012. The Price Indexes were calculated with the average of the annual real data deflated for December 2012 and, to assess the relation between the data and the macroeconomic variables, Pearson’s correlation coefficient was used. The results indicated an increase of 0.08% in real costs of the ureic glue and a reduction of 2.7%, 4.7% 9.9% and 11.7% of the input costs: electricity, phenolic glue, sawn wood and diesel, respectively. Nevertheless, this decrease in the inputs costs was much lower than the 26% decrease in the price received by the plywood industry in the analyzed period. The veneer wood, however, followed the reduction in prices and had a fall of 25%; in contrast, the workforce had an increase of 63%. There was a sharper drop in the price of the final product than the unit costs of inputs. The analysis allows a compression of the contribution margin and a large influence of macroeconomic variables in the sale price and in the components of the production cost of manufacturing plywood. © 2017, Universidade Federal de Santa Maria. All rights reserved.

Modes K.S.,Federal University of Santa Catarina | Santini E.J.,Federal University of Santa Maria | Vivian M.A.,Federal University of Santa Catarina | Haselein C.R.,Federal University of Santa Maria
Ciencia Florestal | Year: 2017

This study investigated the effect of thermal treatment, employed under two treatment conditions on mechanical properties of wood of Pinus taeda L. and Eucalyptus grandis W. Hill ex Maiden. From each species, three 25-year tress were sampled, and from each one, it was taken the first 2-meter long log, which was obtained from two boards of size 7,0 x 20,0 cm (thickness x width respectively) diametrically opposite from where 30 specimens were saw for each treatment. At the first one, called the combined one, the woods were subjected to heat treatment by autoclaving at 130 / ± 3°C and pressure of 2 kgf / cm 2 for 3 hours and, after a conditioning period, subjected to heat in an electric oven at 160 / ± 1°C for the same period. The second treatment consisted only of heat treatment in oven. It was also evaluated the pieces of wood without treatment (control). The mechanical properties were evaluated by means of tests for determining the modulus of elasticity and rupture in bending, maximum resistance to compression parallel to the grain and Janka hardness according to ASTM D 143 (1995), and the impact resistance according to ABNT NBR 7190 (1997). For Pinus taeda wood, it was observed that treatment in an oven gave the worst outcomes, both due to the reduction in the values of supported load of a greater number of mechanical properties evaluated, but also as compared to the lowest increments in resistance when it was observed an increase to the same ones with heat treatment. In Eucalyptus grandis, the combined treatment decreased the greatest number of mechanical properties of wood. © 2017, Universidade Federal de Santa Maria. All rights reserved.

De Farias J.A.,Federal University of Santa Maria | Schneider P.R.,Federal University of Santa Maria | Biali L.J.,Federal University of Santa Maria
Ciencia Florestal | Year: 2017

The present study aims to make a diagnosis of the forests planted in the basin of ‘Pardo’ river (Rio Pardo), in RS state, by contemplating the characterization of properties, of forestations, and of the availability and consumption of wood in the region. The area of reach of the study is in the central region of Rio Grande do Sul state, which main economy is the tobacco crop, enclosing 13 cities that compose the performance area of the Management Committee of Rio Pardo Hydrographic Basin. The data collect were conducted during year 2008. In order to determine the size of the sample, it was made a sampling with its probability proportional to the size, where the criterion of the sample unity distribution took in consideration the numbers of trees per city and, inside the cities, the number of trees per class of property size. The sampling method utilized on the forest inventory was by Prodan, in addition to interviews taken with the producers. The region is characterized by small agricultural producers, and 61.4% of the firewood used in the cure of tobacco leaves is acquired from others, moreover, the majority of the forestation possess reduced spacing (2.26 m²/plant) and low survival indices, in order of the 34.4% after 7 years of the plantation. The wooden current supply is of 2,781.069 m3, what guarantees a supplying for only 3.5 years. The collected data allow to evidence that the resources necessary to invest in the self-sufficiency of firewood for the crop tobacco, are of R$ 12,250,000,00, that could be placed annually, during seven years, equivalent the rotation in simple coppice, resulting in an area of 80 ha/year/city. © 2017, Universidade Federal de Santa Maria. All rights reserved.

Comin A.N.,Federal University of Santa Maria | Acevedo O.C.,Federal University of Santa Maria
Advances in Meteorology | Year: 2017

The convergence zone induced by sea breeze systems over Antarctic Peninsula is analyzed for the summer season of 2013-2015. 59 days, selected by satellite images for the absence of major synoptic forcing, are simulated using the WRF model. Sea breeze convergence has been detected in 21 of these days, mostly during evening hours and under large-scale winds. Breeze events are associated with a cold anomaly at the peninsula with respect to the climatology. This condition favors the onset of the necessary horizontal thermal gradients to trigger the breeze circulation. At the same time, no anomaly of the average pressure at sea level is found, indicating that events are favored when the average synoptic flow is present. Case studies indicate that the convergence location over the peninsula is controlled by the synoptic wind. An average convergence over the peninsula happens from 14:00 to 22:30 UTC, with a maximum at 18:00 UTC. There is a strong potential temperature gradient between the surface of the peninsula and the sea, with the sea breeze circulation system extending up to 1.2 km or higher. The sensible heat flux reaches 80 W/m2 at the top of mountains and 10 W/m2 near the coast. © 2017 Alcimoni Nelci Comin and Otávio Costa Acevedo.

Pivetta L.C.,Instituto Federal Of Rondonia Ifro | Sartori H.C.,Federal University of Santa Maria | Pinheiro J.R.,Federal University of Santa Maria
Journal of Control, Automation and Electrical Systems | Year: 2017

Research efforts focusing on algorithms, techniques, and methods for the design of static converters are currently underway, mainly exploring the minimization of volume, losses, and costs. Such tasks are not trivial even for an expert design engineer. Taking into account the previous considerations, this paper presents a computational tool to quickly and effectively create the design of static converters having as objective function to minimize its volume, losses, and cost. A computational framework called Advanced Design System for Power Converters was developed, where the design of a static converter is created based on the chosen topology, input specification data, recommendations and standards, and databases of components and devices. The language used for the development was Java 8, and the database management system was PostgreSQL. The results obtained through graphics and reports allow the designer to view different designs and results for a chosen set of technologies and component combinations for the assembly of a static converter prototype. As a result, designing of a power converter with the specifications set by the designer is faster and less complex than if it were done manually or with the aid of nonspecific tools for this purpose. © 2016, Brazilian Society for Automatics--SBA.

Carnielutti F.,Federal University of Santa Maria | Pinheiro H.,Federal University of Santa Maria
IEEE Transactions on Industrial Electronics | Year: 2017

This paper proposes a generalized hybrid modulation strategy to extend the operation of asymmetrical cascaded multilevel converters into the overmodulation region during fault conditions on the power cells. The proposed strategy makes use of the advantages of both space vector and carrier-based geometrical modulations to allow the converter to operate with a wide range of modulation indexes and fault conditions. Also, it does not need to precalculate various trajectories for the voltage reference, which would be a very complex task, as the shape of the converter space vector diagram is different for each type of fault condition. It is shown that different kinds of overmodulation can happen during faults on the power cells, and solutions are presented for each mode of operation. Finally, simulation and experimental results are shown to demonstrate the good performance of the proposed modulation strategy. © 2016 IEEE.

Santos R.F.,Federal University of Santa Maria | Carvalho G.S.,Federal University of Santa Maria | Duarte F.A.,Federal University of Santa Maria | Bolzan R.C.,Federal University of Santa Maria | Flores E.M.M.,Federal University of Santa Maria
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2017

In this work, Cr, Cu, Mn, Na and Ni were determined in high purity polyimides (99.5%) by solid sampling graphite furnace atomic absorption spectrometry (SS-GFAAS) using Zeeman effect background correction system with variable magnetic field, making possible the simultaneous measurement at high or low sensitivity. The following analytical parameters were evaluated: pyrolysis and atomization temperatures, feasibility of calibration with aqueous solution, linear calibration range, sample mass range and the use of chemical modifier. Calibration with aqueous standard solutions was feasible for all analytes. No under or overestimated results were observed and up to 10 mg sample could be introduced on the platform for the determination of Cr, Cu, Mn, Na and Ni. The relative standard deviation ranged from 3 to 20%. The limits of detection (LODs) achieved using the high sensitivity mode were as low as 7.0, 2.5, 1.7, 17 and 0.12 ng g− 1 for Cr, Cu, Mn, Na and Ni, respectively. No addition of chemical modifier was necessary, except for Mn determination where Pd was required. The accuracy was evaluated by analyte spike and by comparison of the results with those obtained by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry after microwave-assisted digestion in a single reaction chamber system and also by neutron activation analysis. No difference among the results obtained by SS-GFAAS and those obtained by alternative analytical methods using independent techniques. SS-GFAAS method showed some advantages, such as the determination of metallic contaminants in high purity polyimides with practically no sample preparation, very low LODs, calibration with aqueous standards and determination in a wide range of concentration. © 2017 Elsevier B.V.

Oliveira V.A.,Federal University of Santa Catarina | Iglesias B.A.,Federal University of Santa Maria | Auras B.L.,Federal University of Santa Catarina | Neves A.,Federal University of Santa Catarina | Terenzi H.,Federal University of Santa Catarina
Dalton Transactions | Year: 2017

In this work, we evaluate the interaction of the peripheral Pt(bpy)Cl+ substituted porphyrins, H2PtPor and ZnPtPor with DNA using UV-vis, emission fluorescence, CD spectroscopy, and DNA melting properties altered by the Pt(ii)-porphyrinoid compounds. Additionally, we observe the ability of these porphyrin derivatives to generate 1O2 and to efficiently photocleave plasmid DNA upon visible light irradiation based on a mixed (oxidative/hydrolytic) mechanism. This journal is © The Royal Society of Chemistry.

de Souza M.V.,Nucleo de Pos Graduacao em Fisica | da Silva J.A.,Nucleo de Pos Graduacao em Fisica | Silva L.S.,Nucleo de Pos Graduacao em Fisica | Silva L.S.,Federal University of Santa Maria
Journal of Magnetism and Magnetic Materials | Year: 2017

We report the magneto-thermal and resistive properties of rare-earth dialuminide NdAl2, including spin reorientation transition. To this purpose, we used a theoretical model that considers the interactions of exchange and Zeeman, besides the anisotropy due to the electrical crystal field. The theoretical results obtained were compared to experimental data of the NdAl2 in single crystal and bulk forms. Explicitly, we have calculated the anisotropic variation of magnetic entropy with the magnetic field oriented along the three principal crystallographic directions: [100], [110], and [111] of NdAl2 single crystal, where a signature of the spin reorientation is observed in the [110] and [111] directions. Moreover, of magnetoresistivity we consider the applied magnetic field along the crystallographic directions [100] and [110]. In turn, for the polycrystalline form, the good agreement between theory and experiment confirms the presence of spin reorientation, which was predicted theoretically in magnetization curves. © 2016 Elsevier B.V.

Feldman V.,University of the Republic of Uruguay | Maziero J.,University of the Republic of Uruguay | Maziero J.,Federal University of Santa Maria | Auyuanet A.,University of the Republic of Uruguay
Quantum Information Processing | Year: 2017

In this article, by considering Bell-diagonal two-qubit initial states under local dynamics generated by the Phase Damping, Bit Flip, Phase Flip, Bit Phase Flip, and Depolarizing channels, we report some elegant direct-dynamical relations between geometric measures of Entanglement and Discord. The complex scenario appearing already in this simplified case study indicates that a similarly simple relation shall hardly be found in more general situations. © 2017, Springer Science+Business Media New York.

Fagundez J.L.S.,Federal University of Santa Maria | Sari R.L.,Federal University of Santa Maria | Mayer F.D.,Federal University of Santa Maria | Martins M.E.S.,Federal University of Santa Maria | Salau N.P.G.,Federal University of Santa Maria
Applied Thermal Engineering | Year: 2017

Studies are unanimous that the greatest fraction of the energy necessary to produce hydrous ethanol fuel (HEF), i.e. above 95%v/v of ethanol in water, is spent on water removal (distillation). Previous works have assessed the energy efficiency of HEF; but few, if any, have done the same for wet ethanol fuel (sub-azeotropic hydrous ethanol). Hence, a new metric called net energy factor (NEF) is proposed to calculate the energy efficiency of wet ethanol and HEF. NEF calculates the ratio of Lower Heating Value (LHV) derived from ethanol fuel, total energy out, to energy used to obtain ethanol fuel as distillate, total energy in. Distillation tests were performed batchwise to obtain as distillate HEF and four different fuel blends of wet ethanol with a range from 60%v/v to 90%v/v of ethanol and the amount of energy spent to distillate each ethanol fuel calculated. The efficiency parameters of a SI engine operating with the produced ethanol fuels was tested to calculate their respective conversion efficiency. The results of net energy factors show a clear advantage of wet ethanol fuels over HEF; the optimal efficiency was wet ethanol fuel with 70%v/v of ethanol. © 2016 Elsevier Ltd

Monego D.L.,Federal University of Santa Maria | da Rosa M.B.,Federal University of Santa Maria | do Nascimento P.C.,Federal University of Santa Maria
Food Chemistry | Year: 2017

A summary of the various quantum chemical analyses that have been employed to evaluate the free radical scavenger capacity of carotenoid molecules are tabulated in this review and the most important observations are discussed. These molecules are able to interact with reactive oxygen species through singlet oxygen scavenging, electron transfer, hydrogen atom abstraction and radical adduct formation. Most studies employ density functional theory to compare the antiradical capacity of different carotenoids with the ones that are most explored theoretically, such as lycopene and β-carotene. A significant number of these applications have been directed towards understanding the electron transfer mechanism, and a useful tool called the FEDAM (full-electron donor-acceptor map) was developed to better evaluate this mechanism. Important aspects that may affect the radical scavenging capacity of carotenoids, such as synergistic effects and solubility, are sometimes overlooked, and a greater number of such compounds should be explored. © 2016 Elsevier Ltd

Toso M.A.,Federal University of Santa Maria | Gomes H.M.,Federal University of Rio Grande do Sul | de Brito J.L.V.,University of Brasilia
Journal of Constructional Steel Research | Year: 2017

Composite footbridges are slender civil structures that may be affected by the load action of walking pedestrians resulting in large deflections or even uncomfortable vibrations. There are several ways to model the load action of walking pedestrians on footbridges, but force-only models have been preferred by researchers and standards due to simplicity and good agreement with some measure data in real situations. However, there are some concerns relating to force only models as they do not capture important interaction effects between structure and pedestrians. Important features for force-only model implementation are often neglected by engineers such as the spatiality of the load application and the right synchronization among load components. These features bring more relevance for the simulated data and explain some structural behavior and discrepancies present in analysis using simple force-only models. In this paper, a fully synchronized force model for walking pedestrians is proposed and the effect of such model is compared with a simple force-only model and experimental vibration data obtained in a real composite footbridge. Pedestrians are treated as individuals with intrinsic kinetic and kinematic parameters that are correlated by a measured correlation matrix obtained by the use of a force platform for several pedestrians in laboratory conditions. Pedestrian parameters also follow defined Gaussian probability distribution functions with measured mean and standard deviation. A crowd situation is analyzed and the effect of the fully synchronized force model is assessed. The proposed force model provides a more accurate description of the walking forces applied by the pedestrians. © 2017 Elsevier Ltd

Pillon Barcelos R.,University Of Passo Fundo | Pillon Barcelos R.,Federal University of Santa Maria | Freire Royes L.F.,Federal University of Santa Maria | Gonzalez-Gallego J.,University of León | Bresciani G.,Pontifical Catholic University of Valparaíso
Free Radical Research | Year: 2017

The liver is remarkably important during exercise outcomes due to its contribution to detoxification, synthesis, and release of biomolecules, and energy supply to the exercising muscles. Recently, liver has been also shown to play an important role in redox status and inflammatory modulation during exercise. However, while several studies have described the adaptations of skeletal muscles to acute and chronic exercise, hepatic changes are still scarcely investigated. Indeed, acute intense exercise challenges the liver with increased reactive oxygen species (ROS) and inflammation onset, whereas regular training induces hepatic antioxidant and anti-inflammatory improvements. Acute and regular exercise protocols in combination with antioxidant and anti-inflammatory supplementation have been also tested to verify hepatic adaptations to exercise. Although positive results have been reported in some acute models, several studies have shown an increased exercise-related stress upon liver. A similar trend has been observed during training: while synergistic effects of training and antioxidant/anti-inflammatory supplementations have been occasionally found, others reported a blunting of relevant adaptations to exercise, following the patterns described in skeletal muscles. This review discusses current data regarding liver responses and adaptation to acute and regular exercise protocols alone or combined with antioxidant and anti-inflammatory supplementation. The understanding of the mechanisms behind these modulations is of interest for both exercise-related health and performance outcomes. © 2017 Informa UK Limited, trading as Taylor & Francis Group.

Beck F.,Federal University of Santa Maria | Rigue J.N.,Federal University of Santa Maria | Carara M.,Federal University of Santa Maria
Journal of Magnetism and Magnetic Materials | Year: 2017

We have studied the domain wall dynamics in Joule-annealed amorphous glass-covered microwires with positive magnetostriction in the presence of an electric current, in order to evaluate the profile and shape of the moving domain wall. Such microwires are known to present magnetic bi-stability when axially magnetized. The single domain wall dynamics was evaluated under different conditions, under an axially applied stress and an electric current. We have observed the well known increasing of the domain wall damping with the applied stress due to the increase in the magnetoelastic anisotropy and, when the current is applied, depending on the current intensity and direction, a modification on the axial domain wall damping. When the orthogonal motion of the domain wall is considered, we have observed that the associated velocity present a smaller dependence on the applied current intensity. It was observed a modification on both the domain wall shape and length. In a general way, the domain wall evolves from a bell shape to a parabolic shape as the current intensity is increased. The results were explained in terms of the change in the magnetic energy promoted by the additional Oersted field. © 2017

Schmidt M.,Federal University of Santa Maria | Zimmer F.M.,Federal University of Santa Maria | Magalhaes S.G.,Federal University of Rio Grande do Sul
Journal of Physics Condensed Matter | Year: 2017

The interplay between geometric frustration (GF) and bond disorder is studied in the Ising kagome lattice within a cluster approach. The model considers antiferromagnetic short-range couplings and long-range intercluster disordered interactions. The replica formalism is used to obtain an effective single cluster model from where the thermodynamics is analyzed by exact diagonalization. We found that the presence of GF can introduce cluster freezing at very low levels of disorder. The system exhibits an entropy plateau followed by a large entropy drop close to the freezing temperature. In this scenario, a spin-liquid (SL) behavior prevents conventional long-range order, but an infinitesimal disorder picks out uncompensated cluster states from the multi-degenerate SL regime, potentializing the intercluster-disordered coupling and bringing the cluster spin-glass state. To summarize, our results suggest that the SL state combined with low levels of disorder can activate small clusters, providing hypersensitivity to the freezing process in geometrically frustrated materials and playing a key role in the glassy stabilization. We propose that this physical mechanism could be present in several geometrically frustrated materials. In particular, we discuss our results in connection with the recent experimental investigations of the Ising kagome compound Co3Mg(OH)6Cl2. © 2017 IOP Publishing Ltd.

Vianna E.A.L.,Federal University of Santa Maria | Abaide A.R.,Federal University of Santa Maria | Canha L.N.,Federal University of Santa Maria | Miranda V.,INESC Porto
Electric Power Systems Research | Year: 2017

This paper presents a new methodology to define a priority scale for maintenance actions in substations, based on the development of a Composite Risk Index (CRI) associated with each device. Two auxiliary indices are built: Basic Condition (BC) and Operating Condition (OC), representing the physical and functional characteristics of the equipment that can compromise their performance and contribute to the occurrence of failures. Their evaluation is helped by a Technical Capacity Index (TCI), which evaluates how much the equipment has been affected by wear and tear, in the assessment of the Basic Condition, and the classification of the equipment defects by degrees of severity, in the assessment of the Operating Condition. Two cascading Fuzzy Inference Systems of the Mandani type are used, the first in defining the BC, and the second to obtain the equipment CRI denoting maintenance priority, which may then be used in planning maintenance actions. The methodology is verified through an SF6 circuit breaker CRI assessment, and its priority scale for maintenance planning. The method for evaluating the SF6 circuit breakers reliability is validated through a comparison with a statistical approach, using real data collected from equipment installed in Eletrobras Eletronorte Transmission System, in Rondônia, Amazon region of Brazil. © 2016

de Moraes M.T.,Federal University of Paraná | Debiasi H.,Embrapa Soybean | Carlesso R.,Federal University of Santa Maria | Franchini J.C.,Embrapa Soybean | And 2 more authors.
Soil and Tillage Research | Year: 2017

Soil strength is not only affected by water content and bulk density, but also by the age-hardening phenomena, which plays a key role in increasing the soil strength as a function of time. It has been demonstrated that soil penetration resistance in no-tillage is higher when compared with other tillage systems at the same bulk density and water content. The objectives of this study was to investigate the effects of the age-hardening phenomena on soil penetration resistance in a long-term soil management system, running since 1988 in a very clayey Oxisol, in southern Brazil. Soil samples were collected from three soil layers (0.0–0.10 m; 0.10–0.20 m and 0.20–0.30 m) and five soil tillage systems: conventional tillage; minimum tillage with chiselling performed every year or every three years; and no-tillage for 11 or 24 years. Age-hardening was investigated using soil penetration resistance analysis and modelling. We used the area under the soil resistance to penetration curve to compare the age-hardening phenomena under the different tillage systems. For the same bulk density and water content, the soil resistance to penetration increased with time under no-tillage or without soil chiselling. For the same bulk density, no differences were found for macroporosity and microporosity among the tillage systems. Higher soil penetration resistance values in long-term no-tillage at the same soil bulk density and water content were attributed to the age-hardening phenomena, which increased the number and strength of bonds among soil particles, leading to higher soil cohesion. It is necessary to establish critical limits of soil penetration resistance as a function of the soil tillage system, and the time without soil chiselling or under no-tillage system. © 2017 Elsevier B.V.

Somavilla A.,Federal University of Santa Maria | Gubiani P.I.,Federal University of Santa Maria | Reichert J.M.,Federal University of Santa Maria | Reinert D.J.,Federal University of Santa Maria | Zwirtes A.L.,Federal University of Santa Maria
Soil and Tillage Research | Year: 2017

The soil precompression stress (σp) has been used as an estimator of the soil load bearing capacity, but a few researches have evaluated the correspondence to each other. In this study, we first evaluated in prepared soil cores the time needed for σp to reach a quasi-stable state. Afterwards, we waited the same time for using another set of soil cores to evaluate the changes on σp after the soil core received loads equal to its σp. The two experiments were performed using two Rhodic Hapludox (RH1 and RH2) and one Typic Paleodult (TP). In both experiments the σp was denominated as σp2R, because it was calculated using the two-line intersect method proposed by Dias Junior and Pierce (1995). In the first one, σp2R increased asymptotically over time after sample preparation. When the increasing rate of σp2R decreased down to 0.05 kPa d−1, we assumed that the increase in soil structure strength over time was small and had little effect on σp2R, which took place at 21 days for RH1, 26 days for RH2, and less than 1 day for TP. The second experiment was performed after these times of structure strengthening. Four times in each soil, the σp2R was measured (σp2Ri) and this value was applied as a new load on the soil. Thus, σp2Ri was assumed as the maximum load previously received by the soil core, which was related to the subsequently measured σp2R(σp2Ri+1). The results indicate that σp2R overestimated the maximum load previously received by the soil, because the σp2Ri+1 was generally greater than σp2Ri. Also there were evidences that applying on soil a load equal to σp2R can increase soil compaction. If this tendency is confirmed by further studies using more sensitive techniques to evaluate soil structure changes, as computed tomography, the load limit to be applied to the soil should be less than σp2R because loads equal to such value may overcome the soil load bearing capacity and progressively increase in the degree-of-compactness. © 2017 Elsevier B.V.

Bevilacqua A.C.,Federal University of Santa Maria | Kohler M.H.,Federal University of Rio Grande do Sul | Azevedo S.,Federal University of Paraiba | Baierle R.J.,Federal University of Santa Maria
Physical Chemistry Chemical Physics | Year: 2017

Spin polarized density functional theory has been used to study the stability, and electronic and optical properties when BN nanodomains are embedded in graphene and carbon patches are embedded in a single layer of h-BN forming h-BNC nanosystems. Our results show that graphene doped with BN nanodomains exhibits a non-zero gap, which depends on the nanodomain's shape and width. For h-BN with C domains we observe that we can tune the h-BN gap into the visible region, making the h-BNC a promising material for catalysis using solar energy. Furthermore, n-type and p-type semiconductors can be obtained by controlling the bond (C-N or C-B) in the border of the domain. These findings open the possibility to use h-BNC nanosheets for future applications in photocatalysis and optoelectronic devices. © the Owner Societies 2017.

Holthusen D.,Federal University of Santa Maria | Pertile P.,Federal University of Santa Maria | Reichert J.M.,Federal University of Santa Maria | Horn R.,University of Kiel
Geoderma | Year: 2017

Although there are evidences that most, if not all, soil physical and mechanical processes on larger scales have their origin in processes and properties at the microscale, the range of methods to investigate micro-scaled soil behavior directly is limited. One method to detect flow and deformation behavior under steady and transient stresses is rheometry. This method is well established by means of the amplitude sweep test (AST) to detect viscoelastic properties of soils, i.e. stress-strain relationships under transient stresses that occur due to wheeling or trampling. This test is based upon a soil sample positioned between two parallel plates, where the upper plate rotates in an oscillatory manner with increasing stress or strain amplitude, and the lower plate is fixed. Depending on the retardation of the sample's shear stress reaction, viscous and elastic strain proportions are defined with the help of storage and loss modulus (G′ and G″), and their ratio (tan δ). However, the AST is strongly susceptible to sample preparation and the vertical force of the upper plate. Either a low force (e.g. 1 N) was applied or samples with forces beyond a critical limit (e.g. 12–15 N) were excluded. We used controlled force of 1, 3 and 10 N, equivalent to compressive stresses of 2.04, 6.11 and 20.37 kPa, to find the optimum settings to run the AST. The selected forces/stresses are either low, intermediate or high compared to those observed under undefined conditions in two South Brazilian soils (A and B horizon of a Typic Hapludox – Oxisol, and an Oxyaquic Hapluderts – Vertisol). Furthermore, field density and a common (high) density were applied to the homogenized soil material. The variability of the results generally decreased with increasing compressive stress level, and at highest stress variability was lower than under variable force/stress. The microaggregation of the Oxisol based upon iron oxides and hydroxides (pseudosand) and high kaolinite content in the B horizon resulted in a smaller range of recoverable elasticity than in the Vertisol. However, at large strains the elasticity was higher in the Oxisol, while the Vertisol exhibited alignment of the soil particles. The Oxisol generally showed a brittle rupture by means of a maximum shear stress; while in the Vertisol yielding occurred due to expandable clay. High compressive force and density simultaneously reduced the share of elastic deformation and promoted plastic yielding. The results do not allow yet defining an optimum compressive stress. Thus, we suggest investigating further force or stress levels and to test more soils, e.g. of high soil organic matter content and/or high or low clay, silt or sand content. © 2017 Elsevier B.V.

Magnus L.Z.,Federal University of Santa Maria | Machado R.F.,Federal University of Santa Maria | Caceres N.,Federal University of Santa Maria
Zoologischer Anzeiger | Year: 2017

Environmental pressures are key mechanisms in the change of size or shape of an organism. In addition to external factors, the pressure of allometry (size-related shape changes) can also be present itself in the way that shape varies even in adulthood. In this study, we used a geometric morphometric approach to analyse skull size and shape variation in South-American Didelphidae, genus Caluromys, represented by two species, Caluromys philander and C. lanatus, in relation to allometry, geography and climate. We found significant allometric effects on these species, especially C. lanatus. The strong role of geographical space mainly on size of both species and on shape of C. lanatus suggests that they are spatially structured, supporting neutral processes, such as drift, in their evolution. Size of both species was related to latitudinal variation, the inverse pattern of Bergmann's rule. Temperature and the set of bioclimatic variables influenced both size and shape of species. The shape of C. philander was influenced by bioclimatic variables (e.g. rainfall), while the shape of C. lanatus showed such influence (mostly temperature) but just when under the presence of allometry. Our results indicate the importance of allometry and environment in the patterns of skull shape variation in the South-American Caluromys, with a concomitant influence of geography. Climatic factors, such as the temperature, have strong influence on cranial changes along populations, with the two species varying similarly in skull size and shape along a climatic gradient. The latitudinal distribution, although mostly parapatric, of these congeneric species in South America should be in part responsible for their similarities in the observed phenotypic variation. © 2017 Elsevier GmbH

Magnus L.Z.,Federal University of Santa Maria | Caceres N.,Federal University of Santa Maria
Mammalia | Year: 2017

Tribosphenic molars are considered great innovations in mammals and are related to several structures and variables that can explain adaptation. The aim of this study was to investigate the importance of body size and habitat relation, using a phylogenetic approach, in the first lower molar shape in didelphid marsupials. Geometric morphometric analyses of the lower molar's shape were performed on 261 specimens, 130 females and 131 males, covering 14 genera and 37 species of the Didelphidae family. The molar conformation showed a larger talonid in relation to the trigonid in more arboreal genera, and narrower and longer molars in genera with a larger body size. Phylogeny was the variable with the highest explanation for both females and males (16.17% and 9.02%, respectively). The body size was significant in males, presenting an important influence on molar shape, while the body size in females was not significant when phylogenetic relationship was controlled for. In both sexes, habitat presents a strong effect of phylogeny, with no direct effect on molar shape. Didelphid molar shape is another result of its phylogenetic history and does not respond very much to environmental pressures. Male body size influences molar shape in didelphids, even in the presence of a strong phylogenetic signal. © 2017 Walter de Gruyter GmbH, Berlin/Boston.

Lana da Silva C.D.,Federal University of Santa Maria | Cardoso G.,Federal University of Santa Maria | de Morais A.P.,Federal University of Santa Maria | Marchesan G.,Federal University of Pampa | Kaehler Guarda F.G.,Federal University of Santa Maria
Electric Power Systems Research | Year: 2017

Distance relays are protective devices which main goal is the protection of transmission lines. However, the presence of harmonics and the exponentially decaying DC offset in the system voltage and current signals negatively affects the relay performance. In this paper, an adaptive phasor estimation method based on Artificial Neural Networks is presented to reduce these components’ effects, focusing on impedance estimation for distance relaying. The method uses the multilayer perceptron architecture to estimate the current and voltage signals, and then proceeds to calculate the complex apparent impedance during a continually online training process. This online training allows for adaptability regarding the system frequency, providing tolerance against its deviation. Graphical results of the test cases are presented, comparing the functionality and performance of the proposed algorithm with a Fourier-based method. © 2017 Elsevier B.V.

Melo G.L.,Federal University of Mato Grosso do Sul | Sponchiado J.,Federal University of Santa Maria | Caceres N.C.,Federal University of Santa Maria | Fahrig L.,Carleton University
Biological Conservation | Year: 2017

According to the habitat amount hypothesis the species richness in a sample site should increase with the habitat amount in the local landscape around the sample site. On the other hand, size and isolation of the patch containing the sample site should have no effect on species richness if the habitat amount in the local landscape remains constant. We tested these predictions using a small mammal dataset recorded in 100 transects in a savanna region of Brazil. We used generalized linear models considering the predictors - habitat amount, patch size, and patch isolation - together and singly, using subsets of data to control for correlations between them. We measured the habitat amount in 10 nested circles ranging in radius from 250 m to 6000 m around each transect. The scale of effect was the radius with the strongest estimated correlation between habitat amount and species richness. Our results indicate that habitat amount is the most important single predictor of species richness. The habitat amount effect was always positive and large. In general, patch size and patch isolation had no effect on species richness after controlling for the effect of habitat amount. The results are consistent with the habitat amount hypothesis, and suggest that habitat amount can be used in place of patch size and isolation in predicting small mammal species richness. This simplifies information needs by landscape managers as it replaces two predictors with one. Our results also support the use of estimated dispersal distance as a way of determining the appropriate landscape scale of effect. © 2017 Elsevier Ltd

Schonell A.J.,Federal University of Rio Grande do Sul | Storchi-Bergmann T.,Federal University of Rio Grande do Sul | Riffel R.A.,Federal University of Santa Maria | Riffel R.,Federal University of Rio Grande do Sul
Monthly Notices of the Royal Astronomical Society | Year: 2017

We map the gas excitation and kinematics, and the stellar population properties of the Seyfert 1 galaxy NGC 5548 using Gemini Near Infrared Integral Field Spectrograph in the J and K bands at a spatial and velocity resolution of 105 pc and 45 km s-1, respectively. Emission-line flux distributions in ionized and molecular gas extend up to ≈400 pc from the nucleus, where they are found to peak. The mass of H II is 4.8±0.6 × 106 M⊙ and the mass of warm H2 is 1.1±0.2 × 103 M⊙, while the mass of cold H2 is estimated as 5.8±1.2 × 108 M⊙. The Pa β emission shows two kinematic components: one in blueshift, with velocity reaching ≈-300 km s-1 and another showing a velocity field characteristic of rotation in the galaxy plane. The blueshifted component is also observed in the coronal line [S IX]λ1.2523 μm, while the rotational component is also observed in the molecular gas.We interpret this velocity field as due to gas rotating in the galaxy plane plus an outflow, and estimate a mass outflow rate of 6.8±0.75 M⊙ yr-1. Spectral synthesis of the continuum shows nuclear emission dominated by a featureless AGN continuum combined with hot dust emission attributed to a dusty torus. The stellar population is dominated by an old (2 Gyr < t ≤ 15 Gyr) component between 160 and 300 pc, while closer to the nucleus, an intermediate age (50 Myr < t ≤ 2 Gyr) component contributes at levels ranging from ≈40 per cent to ≈100 per cent to the flux at 2.12 μm. © 2016 The Authors.

Rocha J.B.T.,Federal University of Santa Maria | Piccoli B.C.,Federal University of Santa Maria | Oliveira C.S.,Federal University of Santa Maria
Arkivoc | Year: 2017

This review presents a brief account of the discovery, importance, and use of selenium. Based in the importance of selenoproteins, their mechanism of reaction with the participation of selenium, as a selenol (-SeH) group, are indicated. Since the selenol group is the softest nucleophile center found in life, a brief discussion about the synthesis and possible antioxidant and selenoprotein mimetic effects of the organoselenium compounds that can generate the selenol group is presented.

Correia D.,Federal University of Mato Grosso do Sul | Sauerwein I.P.S.,Federal University of Santa Maria
Revista Brasileira de Ensino de Fisica | Year: 2017

This article analyzes the readings of Popular Science Texts (TDC) done by undergraduates in the disciplines of supervised internship in Physics Teaching II and III. Oral and written records produced during activities with TDC associated with reading strategies were analyzed according to the theoretical frameworks of the analysis of the French Discourse and Education area science. It was observed that polysemic readings were valued in the teaching stages, in which the text-pretext reading strategy was predominant in classes and the discourse used by the students tended to be controversial. Moreover, in the pre-teaching, the TDC function was restricted to the use of texts in order to teach physics. There was an improvement in classes since TDC included the development of oral expression and written skills on the part of students; the articulation between physics contents and learners' daily life; the awakening of interest and motivation due to curiosity on the part of students. Finally, it is inferred that employing TDCs associated to reading strategies in physics classes point to a possible way for the advancement of polysemic readings, besides encouraging the formation of subject-readers within the context of teachers' training and school. © 2017, Sociedade Brasileira de Física. Printed in Brazil.

Recchi A.M.S.,Federal University of Santa Maria | Back D.F.,Federal University of Santa Maria | Zeni G.,Federal University of Santa Maria
Journal of Organic Chemistry | Year: 2017

In this paper, we report an intramolecular cyclization of benzylic-substituted propargyl alcohols promoted by iron(III) chloride and diorganyl diselenides to give 2-organoselenyl-naphthalenes via a sequential carbon-carbon/carbon-selenium bond formation. The present reaction tolerated a wide range of substituents in both propargyl alcohols and diorganyl diselenides to give the desired 2-organoselenyl-naphthalenes in good yields with high selectivity. In addition, O-acyl protected propargyl alcohol and propargyl bromide were also subjected to this protocol giving the corresponding 2-organoselenyl-naphthalenes. We found that dichalcogenide species affected the formation of cyclized products, whereas diorganyl diselenides gave high yields, moderate yields were obtained with diorganyl disulfides, and no product formation was found with diorganyl ditellurides. The key transformations could be attributed to the carbon-carbon triple bond activation of benzylic-substituted propargyl alcohols by a seleniranium ion, antiattack of the electron cloud from the aromatic ring at the activated triple bond, and cyclization via an exclusive 6-endo-dig process. We also found that the corresponding 2-organoselenyl-naphthalenes are suitable substrates to the selenium-lithium exchange reactions followed by trapping with aldehydes affording the corresponding secondary alcohols. © 2017 American Chemical Society.

Canabarro N.I.,Federal University of Santa Maria | Alessio C.,Federal University of Santa Maria | Foletto E.L.,Federal University of Santa Maria | Kuhn R.C.,Federal University of Santa Maria | And 2 more authors.
Renewable Energy | Year: 2017

In this work was presented a sequential strategy to optimize and scale-up the production of ethanol by solid-state saccharification and fermentation using rice bran as substrate. In the first step, fermentation was carried out in Erlenmeyers to study the influence of eight variables by means of a Plackett Burman design. After the choice of most significant ones, a central composite rotational design (CCRD) for three independent variables (rice bran concentration, moisture content and inoculum size) was conceived to optimize the ethanol production in a packed-bed bioreactor. From Erlenmeyers to packed bed bioreactor the process was scaled-up 10 times. Maximum ethanol production in the packed-bed bioreactor was 135 ± 10.8 g kg−1 at inoculum size, rice bran concentration and moisture content of 10% v/v, 62.5% w/w and 65% w/w, respectively. The ethanol yield obtained in the packed-bed bioreactor was similar to that in the erlenmeyers flasks (138.7 g kg−1), validating the strategy adopted for optimization and scale-up. © 2016 Elsevier Ltd

Rosa M.T.,Federal University of Santa Maria | Oliveira D.S.,Federal University of Santa Maria | Loreto E.L.S.,Federal University of Santa Maria
Journal of Zoological Systematics and Evolutionary Research | Year: 2017

The first complete mitochondrial genome of a catenulid, Stenostomum leucops, was characterized. Illumina sequencing and 90 813 reads were utilized in the assembly, producing one contig with an average coverage of 1118×. The length of this genome is 15 742 bp with 12 protein-coding, two rRNA and 22 tRNA genes. Although the atp8 gene is absent in other Platyhelminthes, a highly divergent putative atp8 gene was found in S. leucops. In contrast to other Platyhelminthes, the mitochondrial genes of S. leucops are encoded on both strands. The gene order in the S. leucops mitogenome is very divergent from those observed in other Platyhelminthes, showing only small blocks of synteny. With AAA as the codon for lysine S. leucops shows the probable plesiomorphic condition, whereas Rhabditophora possess the derived GAA. This evolutionary transition is correlated with changes in the respective anticodons in trnK. It remains unclear whether the absence of the D arm and loop in trnS1 is a convergence in Catenulida and Neodermata. © 2017 Blackwell Verlag GmbH

Soares F.Z.M.,Federal University of Santa Maria | Lenzi T.L.,Federal University of Santa Maria | de Oliveira Rocha R.,Federal University of Santa Maria
European Archives of Paediatric Dentistry | Year: 2017

Aim: To evaluate the water storage degradation of resin–dentine bonds of different adhesive systems to primary and permanent human dentine. Methods: Flat occlusal human dentine surfaces of 15 primary molars and 15 permanent molars were randomly assigned according to adhesive systems: Adper Single Bond 2; Clearfil SE Bond and One Up Bond F Plus. After bonding procedures, the adhesives were applied according to the manufacturers’ instructions and composite resin blocks were built. Restored teeth were sectioned rendering rectangular sticks (RS) (0.4 mm2). The RS were submitted to microtensile bond strength (µTBS) test according to the water storage time: 24 h, 1-year, and 2-years. Mean µTBS values were analysed by three-way analysis of variance (mixed design) and Tukey post hoc test (α = 0.05). The failure mode was analysed at 400× magnification. Results: All three factors isolated showed significant influences on µTBS, as did the cross-product interactions between material vs. storage time (p = 0.01) and substrate vs. storage time (p = 0.002). Bond strength means to primary dentine were lower than to permanent dentine (34.7 ± 10.1 and 45.8 ± 12.9 mPa, respectively) after 2-years of water storage. The one-step self-etch adhesive (One Up Bond F Plus) showed less stable bond strength after 2-years of water storage. Conclusion: The resin–dentine bond of primary teeth was more prone to degradation over time compared to permanent dentine. © 2017, European Academy of Paediatric Dentistry.

Molehin O.R.,Ekiti State University, Ado Ekiti | Oloyede O.I.,Ekiti State University, Ado Ekiti | Boligon A.A.,Federal University of Santa Maria
Journal of Applied Pharmaceutical Science | Year: 2017

The present study aimed to investigate the phenolic contents and antioxidant properties of the various leaf extracts (methanol, ethanol, ethyl acetate) of Clerodendrum volubile. The total phenol and total flavonoid contents of the extracts were determined. In vitro scavenging activities of the extracts were assessed against 1, 1-diphenyl-2 picrylhydrazyl (DPPH), 2, 2-azinobis (3-ethylbenzo-thiazoline- 6-sulfonate (ABTS) radical scavenging ability. The reducing power ability and high-performance liquid chromatography-diode-array detector (HPLC-DAD) of the extracts were also determined. The results revealed that methanolic extract had the highest total phenol and total flavonoid contents in all the extracts. The methanol extract had the highest reducing power, DPPH and ABTS radicals scavenging activities, followed by ethanol and ethyl acetate extracts. The HPLC-DAD results revealed the presence of both phenolic acids (caffeic acid, gallic acid) and flavonoids (catechin, quercetin, rutin, quercitrin, kaempferol, luteolin, apigenin) as its major bioactive polyphenolics. The difference in scavenging potential of the extracts may be due to variation in the phytoconstituents extracted using various solvents. The result suggests that the methanol leaf extract of Clerodendrum volubile could serve as a potential source of antioxidants and can be explored as a therapeutic agent in free radical induced diseases. © 2017 Olorunfemi R Molehin et al.

de Souza M.V.,University of Sao Paulo | da Silva J.A.,University of Sao Paulo | Silva L.S.,University of Sao Paulo | Silva L.S.,Federal University of Santa Maria
Journal of Magnetism and Magnetic Materials | Year: 2017

We report the thermodynamic properties of selected intermetallic RAl2 (R = Er, Tm) compounds calculated by using a model Hamiltonian, including the Zeeman-exchange interactions and the crystalline electrical field, which are responsible for the magnetic anisotropy. The relationship between the behavior of the temperature-dependent magnetization, calculated in different crystallographic directions for several magnetic fields, and the influence of spin reorientation on the magnetocaloric effect, is discussed. In order to validate the obtained theoretical results, experimental data are compared to calculated data. Also, an optimum molar fraction of the ErAl2 and TmAl2 composite was determined theoretically, showing a high potential for use in a regenerative thermal cycle, especially close to the liquid helium temperature range. © 2017 Elsevier B.V.

De Franceschi V.D.,Federal University of Santa Maria | Silva M.A.R.,Federal University of Santa Maria
Proceedings of the 15th International Conference WWW/Internet 2016 | Year: 2016

Nowadays, Web has been used in many daily activities as researching, shopping, among others. On the other hand, a considerable part of people, particularly who have special needs, have some difficulties to access and use Web for these and others activities. In this context, we describe here two important strategies for accessibility, one called WCAG which is internationally known and another called eMag, which was defined considering WCAG and others accessible strategies and guidelines. Taking these two strategies into consideration a web site was developed and used by some people with visual impairments. After observation of the use of it and others sites, new guidelines were identified. As result, this paper also presents these new guidelines to be used as WCAG and eMag complement.

Krassmann A.L.,Federal University of Santa Maria | Paschoal L.N.,University of Cruz Alta | Falcade A.,Federal University of Santa Maria | Medina R.D.,Federal University of Santa Maria
Brazilian Symposium on Games and Digital Entertainment, SBGAMES | Year: 2016

This paper conducts a Systematic Mapping in order to outline a current overview of digital serious games applications' evaluations for game-based learning purposes on computer science higher education. The search was performed on informatics' area electronic databases, resulting in 2,174 publications initially found. After sorting through the application of inclusion and exclusion criteria, remained 59. In the final phase, after thorough reading the extracted publications, has come up to 10 papers. The results reveal different practical approaches of digital serious games' applications evaluations that assess its different aspects' influence on students. © 2016 IEEE.

Baroni M.,Federal University of Santa Maria | Almeida M.S.S.,Federal University of Rio de Janeiro
Proceedings of the Institution of Civil Engineers: Geotechnical Engineering | Year: 2017

The compression index, swelling index and preconsolidation stress values are essential for reliable settlement calculations. However, it is a challenge to obtain representative parameters for very soft, organic, high-plasticity clays, which are often found in the Jacarepaguá Lowlands, Rio de Janeiro, Brazil. In recent decades, several geotechnical correlations have been proposed for estimating the parameters to check oedometer test data. The compression index can be estimated based on simple laboratory index tests and the preconsolidation stress can be found by means of piezocone and vane tests. In this paper, data from 24 different investigation clusters located in the region are analysed. Undisturbed samples were collected from 20 different locations; 67 piezocone tests and 48 vane tests were carried out, which resulted in a comprehensive data bank. Then correlations were developed and compared with a number of equations to assess their reliability. Special emphasis was given to correlations between the compression index and soil water content, and also between the preconsolidation stress and the corrected cone resistance and shoulder pore pressure measured in the piezocone tests. © 2017, ICE Publishing. All rights reserved.

Costa E.A.,Federal University of Santa Maria | Schroder T.,Federal University of Santa Maria | Finger C.A.G.,Federal University of Santa Maria
Cerne | Year: 2016

Height-diameter relationships are used in order to make forest inventories less expensive and to assess growth and yield. This study aimed to develop height-diameter models for individual trees of Araucaria angustifolia (Bertol.) Kuntze for different locations and growth conditions in Southern Brazil. Our data include locations of at least one third of this species natural geographical distribution. We used Michailoff’s model, and compared height-diameter tendency through analytical methods. The model showed good overall precision and accuracy. Trees growing in forest conditions had a higher asymptotic height, and reached it at smaller diameters than open-grown trees. Different regions had contrasting height-diameter tendency indicating site potential, especially for natural forests. Individual tree asymptotic height was correlated with site altitude and mean annual precipitation. This study represents a source of parameters for height-diameter relationships in a large geographical span, for a species with high cultural and timber value in Southern Brazil. © 2016, Federal University of Lavras. All rights reserved.

Ceolin J.,Federal University of Santa Maria | Dallepiane L.B.,Federal University of Santa Maria
Mundo da Saude | Year: 2016

Old people represent the part of the population that increases more in the world, and, in Brazil, the population's aging happens in a progressive and fast way. In spite of being a natural process, aging submits the human body to many changes and it can influence directly on the elderly's nutritional status. Based on the above, this study aims to compare the nutritional status using the elderly's nutritional minivaluation in a long stay institution, in a town from Rio Grande do Sul, between 2013 and 2014. This is a quantitative study with retrospective data analysis, analyzing information from 2013 and 2014, extracted from the institutionalized elderly's records using Miniavaliação Nutrition (MNA) as a research instrument. The population of the research was formed by 36 old people, totaling a percentile of 66,7% of women. The diagnosis got from the nutritional minivaluation observed that most institutionalized elderly showed nutritional risk in 2013 (61,1%) as well as in 2014 (58,3%). In relation to innutrition, in 2013 the percentage was 16,7% and in 2014 it increased to 25%. In short,for being a group vulnerable nutricionalty, mainly for taking care of institutionalized seniors, the seriate evaluations are covered of importance in the sense of proposing intervention for the cases with alterations nutricionals.

De Moura Garcia P.,Federal University of Pampa | Kreutz D.L.,Federal University of Pampa | Welfer D.,Federal University of Santa Maria
Proceedings - 2016 29th SIBGRAPI Conference on Graphics, Patterns and Images, SIBGRAPI 2016 | Year: 2016

In this paper we propose a novel method for finding the fovea in colored images of the eye fundus. We use an image correlation coefficient to find the fovea, which is calculated from a set of template images of the fovea. The results, using the DIARETDB1 database, indicate that our method detects the fovea region with an accuracy of 82,02%. © 2016 IEEE.

Balen G.,Federal University of Santa Maria | Pinheiro H.,Federal University of Santa Maria | Schuch L.,Federal University of Santa Maria | Rabenschlag D.R.,Federal University of Santa Maria
EVS 2016 - 29th International Electric Vehicle Symposium | Year: 2016

This paper describes one off-board fast charge station for electric vehicles. The proposed station is modular and expandable with and integrated energy storage unity. The expansible feature allows a reduced up-front investment and permits the site owner to add more charge points when the demand for fast charge increases. In addition, the proposed off board has an energy storage system which allows shaping the power demanded from the grid, reducing power peaks and possibly the total energy cost, since battery bank is used to store energy when few vehicles are connected. The proposed off board fast charge station is comprised of the following blocks: i) transformer operating from a medium voltage grid followed by a twelve pulse non-controlled rectifier with a small active filter; ii) energy storage system; iii) a 600V DC distribution bus; iv) charging end-points composed of buck interleaved converters. Each end-point, which has potentially low cost, complexity and footprint, gives up to 60 kW charge to an electric vehicle. Simulations results are given to demonstrate the feasibility of the proposed off board fast charging. Also, results from current harmonics at the grid side and analysis of converters responses are presented. Moreover, a viability study shows how the battery bank can help the fast charge system to reduce the use of energy from grid during peak hours, making it profitable.

Pesarico A.P.,Federal University of Santa Maria | Rosa S.G.,Federal University of Santa Maria | Stangherlin E.C.,Federal University of Santa Maria | Mantovani A.C.,Federal University of Santa Maria | And 2 more authors.
Journal of Psychiatric Research | Year: 2017

7-Fluoro-1,3-diphenylisoquinoline-1-amine (FDPI) is a promising isoquinoline that elicits an antidepressant-like action in rodents. In this study, an animal model of stress induced by maternal separation was used to investigate the effects of FDPI in Wistar rats of 30 and 90 days of age. It was investigated the effects of maternal separation in the self-care behavior and the contribution of glutamatergic and gamma-aminobutyric acid (GABA)ergic systems in the FDPI action. Male Wistar rats were separated from their mothers for 3 h/day from postnatal day (PND) 1–10. The rats were treated at different ages (PND-30 and PND-90) with FDPI (5 mg/kg, intragastrically/7 days) and performed the splash test. Maternal separation reduced total grooming time in the splash test, an index of motivational and self-care behavior, and FDPI treatment was effective in reversing this behavior in rats at both ages. The neurochemical parameters were differently affected, dependent on the age of rats, by maternal separation and FDPI. Maternal separation increased the GABA uptake and the excitatory amino acid transporter 1 levels in the prefrontal cortices of rats at PND-30 and FDPI was effective against these alterations. At PND-90, maternal separation decreased the glutamate uptake and increased the GABA uptake and the N-methyl-D-aspartate (NMDA) receptor 2B levels in the prefrontal cortices of rats. FDPI reversed the neurochemical alterations caused by maternal separation in the prefrontal cortices of rats at PND-90. The results of this study demonstrated that FDPI reversed the reduction in self-care behavior induced by maternal separation stress in rats by modulating the glutamatergic/GABAergic systems in rats. © 2017 Elsevier Ltd

Schuch A.P.,Federal University of Santa Maria | Moreno N.C.,University of Sao Paulo | Schuch N.J.,Centro Universitario Franciscano | Menck C.F.M.,University of Sao Paulo | Garcia C.C.M.,Federal University of Ouro Preto
Free Radical Biology and Medicine | Year: 2017

The routine and often unavoidable exposure to solar ultraviolet (UV) radiation makes it one of the most significant environmental DNA-damaging agents to which humans are exposed. Sunlight, specifically UVB and UVA, triggers various types of DNA damage. Although sunlight, mainly UVB, is necessary for the production of vitamin D, which is necessary for human health, DNA damage may have several deleterious consequences, such as cell death, mutagenesis, photoaging and cancer. UVA and UVB photons can be directly absorbed not only by DNA, which results in lesions, but also by the chromophores that are present in skin cells. This process leads to the formation of reactive oxygen species, which may indirectly cause DNA damage. Despite many decades of investigation, the discrimination among the consequences of these different types of lesions is not clear. However, human cells have complex systems to avoid the deleterious effects of the reactive species produced by sunlight. These systems include antioxidants, that protect DNA, and mechanisms of DNA damage repair and tolerance. Genetic defects in these mechanisms that have clear harmful effects in the exposed skin are found in several human syndromes. The best known of these is xeroderma pigmentosum (XP), whose patients are defective in the nucleotide excision repair (NER) and translesion synthesis (TLS) pathways. These patients are mainly affected due to UV-induced pyrimidine dimers, but there is growing evidence that XP cells are also defective in the protection against other types of lesions, including oxidized DNA bases. This raises a question regarding the relative roles of the various forms of sunlight-induced DNA damage on skin carcinogenesis and photoaging. Therefore, knowledge of what occurs in XP patients may still bring important contributions to the understanding of the biological impact of sunlight-induced deleterious effects on the skin cells. © 2017 The Authors.

News Article | April 27, 2017

A study in rats, published in Experimental Physiology, showed that resistance exercise recovers memory and motor impairment caused by the flavour enhancer monosodium glutamate. Monosodium glutamate (MSG) is an additive that mimics umami flavour, the fifth taste aside from sweet, sour, salty and bitter. Some studies have shown MSG to have adverse effects in humans, making it important to understand how it works in the body. Giving MSG to new-born rats has previously been shown to cause motor and memory impairment. The team of researchers at the Federal University of Santa Maria in Brazil gave the experimental group of new-born rats a dose of MSG. This dose is not comparable to the dose humans eat. Of the rats that were given MSG, half began a resistance exercise regimen at two months of age. The exercise consisted of climbing a ladder at an 80 degree angle. The rats performed these exercises five times per week for seven weeks. After resistance exercise, researchers tested the rats' motor coordination and memory. Within the group injected with MSG, motor coordination was less impaired in both male and female rats that performed resistance exercise. Memory also improved in both male and female rats, but it was a different type of memory in the two sexes. Recognition memory improved in male rats, whereas female rats had improved location memory. To test both types of memory, researchers present rats with two objects. To test recognition memory, one object is replaced with a new one. To test location memory, one object is moved to a new location. The next question that Cristina Wayne Nogueira, lead investigator, and her team will explore is the mechanism of memory improvement. Commenting on the study, Nogueira said: 'This study highlights that resistance-based exercise improves cognitive deficit induced by a flavour enhancer. Our next goal is to understand how this is happening.'

Magistrali I.C.,Federal University of Santa Maria | dos Anjos N.,Federal University of Viçosa
Ciencia Florestal | Year: 2011

There is great difficulty to improve techniques of integrated pest management of leaf cutting ants, mainly when found outside of, but near to, forest plantations. This work aims to characterize aspects such as nest size and foraging distance from eucalypt plantations. Studies were performed near forest plantations in the counties of João Pinheiro and Buritizeiro, in Minas Gerais State, Brazil. Six months before, all leaf cutting ant nests received chemical control with sulfluramid baits. Nine nests were located outside the eucalypt plantations. Nest area was 62.5 ± 11.1 m 2 and nests were located 33.94 ± 8.68 m from plantation boundary. Such characteristics may be useful to fix the boundary range used to control leaf cutting ant mounds outside the eucalypt plantation. Results show that boundary range should be 50 m wide. Acromyrmex sp. is a new occurrence for both Buritizeiro and João Pinheiro counties, but Atta laevigata, A. sexdens rubropilosa and Trachymyrmex sp. are new occurrences for Buritizeiro only.

Aita C.,Federal University of Santa Maria | Recous S.,French National Institute for Agricultural Research | Cargnin R.H.O.,Federal University of Santa Maria | da Luz L.P.,Federal University of Santa Maria | Giacomini S.J.,Federal University of Santa Maria
Biology and Fertility of Soils | Year: 2012

The joint management of animal manures and plant biomass as straw on agricultural soils may be a viable option for reducing the environmental impacts associated with livestock production and recycling nutrients efficiently. To investigate this option, an incubation in controlled conditions examined how the simultaneous addition of 15N-labeled pig slurry and 13C-labeled wheat straw, either on the soil surface or incorporated into the soil, affected the mineralization of C from the organic materials and the soil N dynamics. Samples from a typic hapludalf were incubated for 95 days at 25°C with eight treatments: unamended soil (S), wheat straw left on the soil surface (Ws), wheat straw incorporated in the soil (Wi), pig slurry on the soil surface (Ps), pig slurry incorporated in the soil (Pi) and three combinations of the two amendments: Pi + Ws, Pi + Wi, and Ws + Ps. Carbon dioxide and 13CO 2 emissions and soil N content were measured throughout the incubation. Pig slurry stimulated the decomposition of straw C only when wheat straw and pig slurry were left together on the soil surface. Incorporation of both wheat straw and pig slurry did not modify straw C mineralization when compared to straw incorporation alone but this promoted a higher rate of N immobilization. The results suggest that when pig slurry is used in field under no-till conditions, the best strategy to preserve environmental quality with regard to CO 2 emissions would be to apply pig slurry underneath the crop residues. © 2012 Springer-Verlag.

Bizzi C.A.,Federal University of Santa Maria | Nobrega J.A.,Federal University of São Carlos | Barin J.S.,Federal University of Santa Maria | Oliveira J.S.S.,Federal University of Santa Maria | And 3 more authors.
Analytica Chimica Acta | Year: 2014

The present work evaluates the influence of vessel cooling simultaneously to microwave-assisted digestion performed in a closed system with diluted HNO3 under O2 pressure. The effect of outside air flow-rates (60-190m3h-1) used for cooling of digestion vessels was evaluated. An improvement in digestion efficiency caused by the reduction of HNO3 partial pressure was observed when using higher air flow-rate (190m3h-1), decreasing the residual carbon content for whole milk powder from 21.7 to 9.3% (lowest and highest air flow-rate, respectively). The use of high air flow-rate outside the digestion vessel resulted in a higher temperature gradient between liquid and gas phases inside the digestion vessel and improved the efficiency of sample digestion. Since a more pronounced temperature gradient was obtained, it contributed for increasing the condensation rate and thus allowed a reduction in the HNO3 partial pressure of the digestion vessel, which improved the regeneration of HNO3. An air flow-rate of 190m3h-1 was selected for digestion of animal fat, bovine liver, ground soybean, non fat milk powder, oregano leaves, potato starch and whole milk powder samples, and a standard reference material of apple leaves (NIST 1515), bovine liver (NIST 1577) and whole milk powder (NIST 8435) for further metals determination by inductively coupled plasma atomic emission spectroscopy (ICP-OES). Results were in agreement with certified values and no interferences caused by matrix effects during the determination step were observed. © 2014.

Godoi M.,Federal University of Santa Catarina | Alberto E.E.,Federal University of Santa Maria | Paixao M.W.,Federal University of São Carlos | Soares L.A.,Federal University of Rio Grande do Sul | And 2 more authors.
Tetrahedron | Year: 2010

A new class of amino-phosphinite chiral ligands was prepared and applied in zinc-catalyzed addition of aryl boronic acids to aldehydes; the reaction furnished the diarylmethanols in excellent yields and with a high level of enantioselectivity (up to 93% ee). © 2009 Elsevier Ltd. All rights reserved.

Dotto G.L.,Federal University of Santa Maria | Buriol C.,Federal University of Santa Maria | Pinto L.A.A.,Grande Rio University
Chemical Engineering Research and Design | Year: 2014

The adsorption kinetics of erythrosine B and indigo carmine on chitosan films was studied by a diffusional mass transfer model. The experimental curves were obtained in batch system under different conditions of stirring rate (80-200rpm) and initial dye concentration (20-100mgL-1). For the model development, external mass transfer and intraparticle diffusion steps were considered and the specific simplifications were based on the system characteristics. The proposed diffusional mass transfer model agreed very well with the experimental curves, indicating that the surface diffusion was the rate limiting step. The external mass transfer coefficient (kf) was dependent of the operating conditions and ranged from 1.32×10-4 to 2.17×10-4ms-1. The values of surface diffusion coefficient (Ds) increased with the initial dye concentration and were in the range from 0.41×10-14 to 22.90×10-14m2s-1. The Biot number ranged from 17.0 to 478.5, confirming that the intraparticle diffusion due to surface diffusion was the rate limiting step in the adsorption of erythrosine B and indigo carmine on chitosan films. © 2014 The Institution of Chemical Engineers.

Duarte F.A.,Grande Rio University | Mello P.D.A.,Federal University of Santa Maria | Bizzi C.A.,Federal University of Santa Maria | Nunes M.A.G.,Federal University of Santa Maria | And 5 more authors.
Fuel | Year: 2011

Ultrasound-assisted oxidative desulfurization (UAOD) process was applied to diesel oil and petroleum product feedstock containing model sulfur compounds (benzothiophene, dibenzothiophene and dimethyldibenzothiophene). The influence of oxidant amount, volume of solvent for the extraction step and time and temperature of ultrasound treatment (20 kHz, 750 W, operating at 40%) was investigated. Using the optimized conditions for UAOD, sulfur removal up to 99% was achieved for model compounds in petroleum product feedstock using a molar proportion for H 2O 2:acetic acid:sulfur of 64:300:1, after 9 min of ultrasound treatment at 90 °C, followed by extraction with methanol (optimized solvent and oil ratio of 0.36). Using the same reagent amount and 9 min of ultrasound the removal of sulfur was higher than 75% for diesel oil samples. Sulfur removal without ultrasound using the same conditions was lower than 82% for model compounds and 55% for diesel oil samples showing that ultrasound improved the efficiency of oxidative desulfurization. In comparison to conventional hydrodesulfurization, the proposed UAOD process can be performed under relatively mild conditions (atmospheric pressure and 90 °C, without using metallic catalysts). © 2011 Elsevier Ltd. All rights reserved.

Dressler V.L.,Federal University of Santa Maria | Antes F.G.,Federal University of Santa Maria | Moreira C.M.,Federal University of Santa Maria | Pozebon D.,Federal University of Rio Grande do Sul | Duarte F.A.,Grande Rio University
International Journal of Mass Spectrometry | Year: 2011

The present review deals with As, Hg, I, Sb, Se, and Sn speciation in biological tissues and body fluids carried out in the last ten years. The focus is inductively coupled plasma mass spectrometry (ICP-MS) as a powerful analytical tool for elemental speciation analysis. Methods based mainly on liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS), gas chromatography-inductively coupled plasma mass spectrometry (GC-ICP-MS), capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICP-MS) are highlighted. Applications of other hyphenated techniques are also included, but in lesser extent. Relevant applications of methodologies used for As, Hg, I, Se, Sb, and Sn speciation in biological tissues and body fluids are cited. © 2011 Elsevier B.V.

Schons K.R.R.,Federal University of Santa Maria | Knob C.F.,Federal University of Santa Maria | Murussi N.,Federal University of Santa Maria | Beber A.A.C.,Federal University of Santa Maria | And 2 more authors.
Anais Brasileiros de Dermatologia | Year: 2014

Nails are considered epidermal appendages, and as such, are commonly affected in patients with psoriasis, 80% of whom are likely to develop nail psoriasis as a result of their condition. Two patterns of nail disorders have been shown to be caused by psoriasis. Nail matrix involvement can result in features such as leukonychia, pitting (punctures or cupuliform depressions), red spots in the lunula and crumbling. Nail bed involvement, on the other hand, can cause onycholysis, salmon or oil-drop patches, subungual hyperkeratosis and splinter hemorrhages. Nail disease causes aesthetic and functional impairment, and is indicative of more severe forms of psoriasis as well as of joint involvement. The treatment for nail psoriasis involves behavioral interventions, topical medications, or systemic therapy in case of extensive skin or joint involvement. This article presents a review of the main features of nail psoriasis, its clinical presentation, diagnostic and assessment methods, clinical repercussions, and of its available treatment options. © 2014 by Anais Brasileiros de Dermatologia.

Camponogara D.,Grande Rio University | Vargas D.R.,Federal University of Santa Maria | Dalla Costa M.A.,Federal University of Santa Maria | Alonso J.M.,University of Oviedo | And 2 more authors.
IEEE Transactions on Industrial Electronics | Year: 2015

This paper presents a new control method and a detailed project methodology for the optimized connection method of two converters, aiming to reduce the redundant power processing, in order to supply high-power light-emitting diodes (LEDs) with reduced capacitance and high efficiency, directly from the ac line. This connection method allows dealing with two major issues related to the LED driver: capacitance reduction and efficiency increasing. The first converter provides power factor correction, whereas the second converter controls the current through the LED. The basic idea consists in making the second converter to process only the low-frequency ripple (LFR) of the first converter, thus smoothing the LED current. In this way, the LFR is managed by the second stage, so that the capacitance of the first stage can be significantly reduced. The proposed control method can achieve better results for the low-frequency compensation. In addition to that, a high power factor and a low harmonic content are obtained, fulfilling the IEC 61000-3-2 Class C requirements. A laboratory prototype with a rated power of 75 W and an input voltage of 220 \hbox{V}-{\rm rms}/60 Hz was built in order to show the feasibility of the idea. The measured overall efficiency of the converter was 91%, and electrolytic capacitors were avoided. © 1982-2012 IEEE.

Da Silva Castiglioni D.,Federal University of Santa Maria | De Lima Da Silva J.V.C.,Federal University of Pernambuco | Dos Santos Azevedo D.,Federal University of Pernambuco
Crustaceana | Year: 2011

The study of relative growth was used to determine the dimensions that best demonstrate the morphological sexual maturity of Ucides cordatus from two mangrove areas (Ariquindá and Mamucabas) of the southern coast of the state of Pernambuco, northeast Brazil. The crabs were collected manually, with a capture effort by one person, during low tide in three different areas (each 25 m 2) during a period of one year from April 2008 to March 2009. Crabs of both sexes were measured for the following dimensions: carapace width (CW); carapace length (CL); major cheliped propodus length (CPL); major cheliped propodus height (CPH); abdomen width (AW) and gonopod length (GL). These variables were subjected to an analysis of K-means clustering followed by a bivariate discriminant analysis, which separated the data into two groups: juveniles and adults. After separation of the groups, each age category was grouped into sixteen size classes of CW and the proportion of adults in each size class was calculated, and fitted to a logistic equation. Subsequently, an interpolation was performed to determine the size at which 50% of the males and females were mature. The relationships that best demonstrated the size at maturity were CPL vs. CW for males (Positive allometry; Ariquindá - juveniles b = 1.27, adults b = 1.41; Mamucabas - juveniles b =1.27, adults b = 1.44) and AW vs. CW for females (Positive allometry; Ariquindá - juveniles b = 1.34, adults b = 1.28; Mamucabas - juveniles b = 1.32, adults b = 1.44). The present analysis indicates that, for these same relationships, 50% of males and females are morphologically mature, at, respectively, 38.0 and 35.4 mm CW in Ariquindá, and 37.3 and 32.9 mm CW in Mamucabas. Positive allometry shown in the female abdomen is related to egg incubation, and the excessive growth observed in the male cheliped must be related to reproductive behaviour, including courtship and intra- or inter-specific agonistic interactions with other males. © 2011 Koninklijke Brill NV, Leiden.

Vieira J.G.,Grande Rio University | Manetti A.G.S.,Grande Rio University | Jacob-Lopes E.,Federal University of Santa Maria | Queiroz M.I.,Grande Rio University
Desalination and Water Treatment | Year: 2012

The dynamic removal of different forms of dissolved and suspended phosphorus (reactive phosphorus, acid-hydrolyzable phosphorus, organic phosphorus and total phosphorus) by the cyanobacteria Aphanothece microscopica Nägeli cultivated heterotrophically in dairy processing wastewater was investigated. Bioreactor performance was highly dependent on operation temperature (10-30°C). Aphanothece microscopica Nägeli was able to uptake not only simple phosphorus species (reactive and acid-hydrolyzable phosphorus), but also complex fractions of organically bound phosphorus. Low bioreactor performance was evidenced by the suspended fractions. The conversion of suspended reactive phosphorus and suspended acid-hydrolyzable phosphorus varied between 50.3% and 93.3%. Suspended organic phosphorus and suspended total phosphorus became erratic, with peaks of phosphorus appearing after 8 h of hydraulic detention time and slightly impacting the global phosphorus balance. In addition to phosphorus removal, a good degree of organic matter and total nitrogen (N-TKN) removal occurred simultaneously. The resulting conversions varied from 64.6% to 96.9% and from 47.2% to 72.8% for chemical oxygen demand and N-TKN, respectively. Rapid biomass growth was verified and the resulting biomass production rates were 0.81-3.85 g l-1 d-1. These results indicate that heterotrophic bioreactors with cyanobacteria have a good potential for phosphorus removal from wastewater. © 2012 Desalination Publications. All rights reserved.

Schumacher R.F.,Federal University of Santa Maria | Rosario A.R.,Federal University of Santa Maria | Souza A.C.G.,Federal University of Santa Maria | Menezes P.H.,Federal University of Pernambuco | Zeni G.,Federal University of Santa Maria
Organic Letters | Year: 2010

Figure presented The synthesis of several highly functionalized 2,3-dihydroselenophenes from homopropargyl selenides via electrophilic cyclization is described. Electrophiles such as I2, ICl, and PhSeBr were used in a simple process employing CH2Cl2 as solvent at room temperature, which gave the cyclized products in high yields. 4-Iodo-2,3-dihydroselenophenes obtained by this methodology were submitted to a dehydrogenation reaction using 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) to give 3-iodoselenophenes. 4-Iodo-5-phenyl-2,3-dihydroselenophene was also submitted to the thiol copper-catalyzed and Heck-type reactions giving the desired products under mild reaction conditions. © 2010 American Chemical Society.

Queiroz M.I.,Grande Rio University | Hornes M.O.,Grande Rio University | da Silva-Manetti A.G.,Grande Rio University | Jacob-Lopes E.,Federal University of Santa Maria
Applied Energy | Year: 2011

In this paper we present and analyse single-cell oil (SCO) production through the cultivation of the cyanobacterium Aphanothece microscopica Nägeli in fish processing wastewater at different temperature levels. The growth data were fitted into four mathematical models (Logistic, Gompertz, modified Gompertz and Baranyi), to define a mathematical expression for describing cell growth. Using statistical criteria, the Logistic model was considered the most adequate one to describe biomass growth. A negative relationship between the percentage of lipid and high growth temperature was evidenced. Mathematical modelling indicates the possibility of obtaining 0.26, 0.36 and 0.44gbiomass/Lreactorday at temperatures of 10, 20 and 30°C, respectively. This results in lipid productivity of 0.04, 0.05 and 0.03glipid/Lreactorday at 10, 20 and 30°C, respectively. © 2010.

Woyciechowsky T.G.,Federal University of Santa Maria | Monticielo M.R.,Federal University of Santa Maria | Keiserman B.,Grande Rio University | Monticielo O.A.,Federal University of Santa Maria
Clinical Rheumatology | Year: 2012

Osteopoikilosis (OPK) is a rare, benign, and asymptomatic bone dysplasia that is developed during childhood and persists throughout life. This condition is generally found incidentally on plain radiographies made by other reasons. The main differential diagnosis is osteoblastic metastasis. So, OPK must be in differential diagnosis when bone lesions are identified on plain radiograph to avoid alarming the patient with more serious disease and misdiagnosis. In this paper, we review the clinical manifestation, pathophysiology, diagnosis, and treatment of OPK. © 2012 Clinical Rheumatology.

Godoi B.,Federal University of Santa Maria | Speranca A.,Federal University of Santa Maria | Bruning C.A.,Federal University of Santa Maria | Back D.F.,Federal University of Santa Maria | And 3 more authors.
Advanced Synthesis and Catalysis | Year: 2011

An efficient and environmentally benign synthesis of 3- organoselenylchromenones was accomplished via iron(III) chloride/diorganyl diselenides-promoted intramolecular 6-endo-dig cyclization of alkynyl aryl ketone derivatives. The cyclization reactions proceeded cleanly under mild reaction conditions, and the desired chromenone derivatives were smoothly isolated in good yields. The methodology proved to be highly regioselective, giving only the six-membered regioisomers and was carried out using iron(III) chloride/diorganyl diselenide at room temperature and under ambient atmosphere, which could be considered an economic and eco-friendly protocol. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Gottlieb M.G.V.,Grande Rio University | Da Cruz I.B.M.,Federal University of Santa Maria | Duarte M.M.F.,Federal University of Santa Maria | Moresco R.N.,Federal University of Santa Maria | And 3 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2010

Context: Metabolic syndrome (MS) is described as a cluster of cardiometabolic risk factors. Studies suggest that ischemia-modified albumin (IMA) is a biomarker of cardiovascular diseases. IMA levels could be associated with cardiometabolic risks and represent a possible indication of microvascular dysfunction in MS patients. Objective: To confirm this possible association, we evaluated the association between IMA levels and MS. Design: We performed a case-control study (32 healthy individuals and 74 subjects with MS) to evaluate the association between MS, IMA, and other biomarkers [high-sensitivity C-reactive protein (hs-CRP), oxidized low-density lipoprotein (OxLDL), oxidized low-density lipoprotein autoantibodies (anti-OxLDL), IL-6, lipid profile, and glucose]. Results: The MS group showed higher levels of IMA (0.618 ± 0.1355) as well as higher levels of hs-CRP, OxLDL, anti-OxLDL, and IL-6 than did control subjects (IMA = 0.338 ± 0.0486) (P < 0.01). Multivariate analysis showed that IMA and MS association was independent of sex, age, diabetes mellitus 2, and hypercholesterolemia. Conclusion: We found an association between IMA and MS. Additional studies including prospective genetic variation approaches need to be performed to help elucidate this association between IMA and MS and its potential clinical role. Copyright © 2010 by The Endocrine Society.

Schmidt K.,Jacobs University Bremen | Garbe-Schonberg D.,University of Kiel | Koschinsky A.,Jacobs University Bremen | Strauss H.,University of Munster | And 3 more authors.
Chemical Geology | Year: 2011

Depending on the geological setting, the interaction of submarine hydrothermal fluids with the host rock leads to distinct energy and mass transfers between the lithosphere and the hydrosphere. The Nibelungen hydrothermal field is located at 8°18'S, about 9km off-axis of the Mid-Atlantic Ridge (MAR). At 3000m water depth, 372°C hot, acidic fluids emanate directly from the bottom, without visible sulfide chimney formation. Hydrothermal fluids obtained in 2009 are characterized by low H2S concentrations (1.1mM), a depletion of B (192μM) relative to seawater, lower Si (13.7mM) and Li (391μM) concentrations relative to basaltic-hosted hydrothermal systems and a large positive Eu anomaly, and display a distinct stable isotope signature of hydrogen (Δ2HH2O=7.6-8.7‰) and of oxygen (Δ18OH2O=2.2-2.4‰).The heavy hydrogen isotopic signature of the Nibelungen fluids is a specific feature of ultramafic-hosted hydrothermal systems and is mainly controlled by the formation of OH-bearing alteration minerals like serpentine, brucite, and tremolite during pervasive serpentinization. New isotopic data obtained for the ultramafic-hosted Logatchev I field at 14°45'N, MAR (Δ2HH2O=3.8-4.2‰) display a similar trend, being clearly distinguished from other, mafic-hosted hydrothermal systems at the MAR.The fluid geochemistry at Nibelungen kept stable since the first sampling campaign in 2006 and is evident for a hybrid alteration of mafic and ultramafic rocks in the subseafloor. Whereas the ultramafic-fingerprint parameters Si, Li, B, Eu anomaly and Δ2HH2O distinguish the Nibelungen field from other hydrothermal systems venting in basaltic settings at similar physico-chemical conditions and are related to the interaction with mantle rocks, the relatively high concentrations of trace alkali elements, Pb, and Tl can only be attributed to the alteration of melt-derived gabbroic rocks. The elemental and isotopic composition of the fluid suggest a multi-step alteration sequence: (1) low- to medium-temperature alteration of gabbroic rocks, (2) pervasive serpentinization at moderate to high temperatures, and (3) limited high-temperature interaction with basaltic rocks during final ascent of the fluid. The integrated water/rock ratio for the Nibelungen hydrothermal system is about 0.5.The fluid compositional fingerprint at Nibelungen is similar to the ultramafic-hosted Logatchev I fluids with respect to key parameters. Some compositional differences can be ascribed to different alteration temperatures and other fluid pathways involving a variety of source rocks, higher water/rock ratios, and sulfide precipitation in the sub-seafloor at Logatchev I. © 2010 Elsevier B.V.

Meili L.,Federal University of Santa Maria | Freire F.B.,Federal University of São Carlos | do Carmo Ferreira M.,Federal University of São Carlos | Freire J.T.,Federal University of São Carlos
Chemical Engineering and Technology | Year: 2012

The influence of vibration number Γ, amplitude A, and frequency of vibration f on the fluid dynamic behavior of a vibrofluidized bed operating with inert particles in the transient period of water evaporation and drying of different solutions was evaluated. The solutions investigated were sewage sludge, skimmed milk, and calcium carbonate of three different solids contents. The impact of feed rate and vibration parameters on the dynamic behavior of variables such as pressure drop and inlet air velocity was determined. Based on the results it was verified that the operation at A = 0.015m improved the bed dynamics and the gas-particle contact in the wetted beds. As different dynamic behaviors may be obtained under the same Γ value, the values of A or f must be informed together with Γ for a complete characterization of vibration effects. The transient period of water evaporation and drying of different solutions was studied to describe the fluid dynamic behavior of a vibrofluidized bed operating with inert particles. The pressure drop and air velocity on the bed were investigated as function of the amplitude, frequency, and dimensionless vibration number. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Meili L.,Federal University of Santa Maria | Daleffe R.V.,Ford Motor Company | Freire J.T.,Federal University of São Carlos
Chemical Engineering and Technology | Year: 2012

The fluid dynamic behavior of a vibrofluidized bed operating with Geldart C particles was studied. The experiments were conducted in order to observe the influence of amplitude, frequency, and dimensionless vibration number on the minimum fluidization velocity, pressure drop, and standard deviation obtained. It was noted that the dimensionless vibration number should be used very carefully if it is to be the unique parameter to set the vibrational effect of the bed fluid dynamics. The results clearly indicate that the fluid dynamic behavior of the bed is very dependent on the different combinations of amplitude and frequency for the same dimensionless vibration number. Therefore, the use of the amplitude or frequency of vibration and the dimensionless vibration number is recommended for a better characterization of the vibrational effects on the fluid dynamic behavior of the particle bed. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diesel V.,Federal University of Santa Maria | Mina Dias M.,Federal University of Viçosa
Journal of Agricultural Education and Extension | Year: 2016

The aim of this study is to analyze the Brazilian experience in designing and implementing an extension policy reform based on agroecology, and reflect on its wider theoretical implications for extension reform literature. Using a critical public policy approach, the study examines political and legal documents as well as recent academic studies for policy frame and implementation. The case reveals the difficulty of implementing an agroecological extension approach as part of the endogenous development proposal expressed in 2004 Rural Extension and Technical Assistance National Policy (PNATER). An extension policy reframing process led to a national contracting-out emphasis, manifested after 2010. The study demonstrates the political economy aspects of extension reform, and how extension policy implementation was conditioned by different and contrasting demands and political-administrative general trends. In the Brazilian experience, a national political centralization and adhesion to new public management principles on administration explains much of extension policy reframe. The study points out the importance of considering political and institutional environments in extension reforms, and indicates a necessity for additional reflection about strategies for scaling up proposals for agroecological and sustainability-oriented extension. © 2016 Wageningen University

Loro V.L.,McMaster University | Loro V.L.,Federal University of Santa Maria | Jorge M.B.,McMaster University | Jorge M.B.,Grande Rio University | And 3 more authors.
Aquatic Toxicology | Year: 2012

Zinc is an essential trace metal, but many aspects of its toxicity remain unclear. In this study, we investigated zinc effects on oxidative stress parameters and antioxidant profile in four tissues (gill, liver, kidney, and white muscle) of Fundulus heteroclitus. Possible interactive effects of salinity were also studied. Killifish were exposed to sublethal level (500μgL -1) of waterborne zinc for 96h in 0% (fresh water), 10% (3.5ppt), 30% (10.5ppt) and 100% sea water (35ppt). Salinity per se had no effect on any parameter in the control groups. Zinc exposure clearly induced oxidative stress, and responses were qualitatively similar amongst different tissues. Salinity acted as a strong protective factor, with the highest levels of reactive oxygen species (ROS) and greatest damage (protein carbonyls, lipid peroxidation as indicated by thiobarbituric acid reactive substances (TBARS) in 0ppt, the least in 100% sea water (35ppt), and gradations in between in many of the observed responses. Increases in total oxidative scavenging capacity (TOSC) occurred at higher salinities, correlated with increases in the activities of superoxide dismutase (SOD) and glutathione-S-tranferase (GST), as well as in tissue glutathione (GSH) concentrations. However, TOSC was depleted in zinc-exposed fish at 0ppt, accompanied by decreases in SOD, GST, GSH, and also catalase (CAT) activity. Our results confirm that sublethal waterborne zinc is an oxidative stressor in fish, and highlight the important protective role of higher salinities in ameliorating the oxidative stress associated with zinc toxicity in this model estuarine teleost. © 2012 Elsevier B.V..

Barros R.C.,University of Sao Paulo | Winck A.T.,Federal University of Santa Maria | Machado K.S.,Grande Rio University | Basgalupp M.P.,Federal University of São Paulo | And 3 more authors.
BMC Bioinformatics | Year: 2012

Background: This paper addresses the prediction of the free energy of binding of a drug candidate with enzyme InhA associated with Mycobacterium tuberculosis. This problem is found within rational drug design, where interactions between drug candidates and target proteins are verified through molecular docking simulations. In this application, it is important not only to correctly predict the free energy of binding, but also to provide a comprehensible model that could be validated by a domain specialist. Decision-tree induction algorithms have been successfully used in drug-design related applications, specially considering that decision trees are simple to understand, interpret, and validate. There are several decision-tree induction algorithms available for general-use, but each one has a bias that makes it more suitable for a particular data distribution. In this article, we propose and investigate the automatic design of decision-tree induction algorithms tailored to particular drug-enzyme binding data sets. We investigate the performance of our new method for evaluating binding conformations of different drug candidates to InhA, and we analyze our findings with respect to decision tree accuracy, comprehensibility, and biological relevance.Results: The empirical analysis indicates that our method is capable of automatically generating decision-tree induction algorithms that significantly outperform the traditional C4.5 algorithm with respect to both accuracy and comprehensibility. In addition, we provide the biological interpretation of the rules generated by our approach, reinforcing the importance of comprehensible predictive models in this particular bioinformatics application.Conclusions: We conclude that automatically designing a decision-tree algorithm tailored to molecular docking data is a promising alternative for the prediction of the free energy from the binding of a drug candidate with a flexible-receptor. © 2012 Barros et al.; licensee BioMed Central Ltd.

Braida J.A.,Federal Technological University of Paraná | Reichert J.M.,Federal University of Santa Maria | Reinert D.J.,Federal University of Santa Maria | da Veiga M.,EPAGRI
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2010

Organic matter accumulation can increase soil resistance to compaction, decreasing the compaction magnitude or its effects. The objective of this study was to establish the effect of soil organic matter accumulation on the compressibility index, which corresponds to soil susceptibility to compaction. The study was performed using samples collected from a Hapludalf and a Hapludox soils in southern Brazil, both having a significant variation in soil organic carbon (SOC) content. Soil compressibility tests were performed under confined conditions, in a uniaxial apparatus by using normal loads of 12.5, 25, 50, 100, 200, 400, 800 and 1600 kPa, and the compressibility index (Cc) was calculated. Soil organic carbon content, bulk density, porosity and water saturation degree were determined too. Results show that soil organic matter content affects the soil compressibility index, however the magnitude and type of effect are dependent upon soil texture and effects associated to soil water retention, cohesion, and bulk density.

Robe L.J.,Federal University of Santa Maria | Robe L.J.,Grande Rio University | MacHado S.,Federal University of Santa Maria | Bartholomei-Santos M.L.,Federal University of Santa Maria
Zoological Science | Year: 2012

DNA-barcoding has recently attracted considerable attention due to its potential utility in aiding in species identification and discovery through the use of a short standardized sequence of mitochondrial DNA. Nevertheless, despite the fact that this technology has been proven a useful tool in several animal taxa, it also demonstrated limitations that may hinder correct application. Thus, its validity needs to be empirically evaluated in each taxonomic category before forward implementation. As the use of DNA barcoding within Palaemonidae may be of special interest, given its great interspecific morphological conservatism associated with considerable intraspecific morphological variation, we analyze here the potential of this technology in distinguishing and recovering some taxonomic boundaries within this family. We asked whether two GenBank-retrieved sets of COI sequences encompassing the conventional Barcode and Jerry-Pat regions possess the desired properties of reciprocal monophyly among species, and existence of a barcoding gap between intra- and interspecific variations, after performing a careful analysis of numt (nuclear mitochondrial DNA) contamination. These analyses revealed nine non-monophyletic species, with some cases of divergent intraspecific sequences, contrasted with interspecific similarity attained in others. Moreover, we were unable to identify any barcoding gap between intraspecific and interspecific divergences within Palaemonidae, although a threshold of 0.18 substitutions per site would differentiate intraspecific and congeneric divergences in 95% of the cases for the barcoding region. A fraction of the overlap could be certainly attributed to artifacts related to poor taxonomy, but even from this perspective DNA barcoding studies may help to uncover previously disregarded taxonomic and evolutionary issues. © 2012 Zoological Society of Japan.

Speranca A.,Federal University of Santa Maria | Godoi B.,Federal University of Rio Grande do Sul | Menezes P.H.,Federal University of Pernambuco | Zeni G.,Federal University of Santa Maria
Synlett | Year: 2013

In this manuscript we described the FeCl3/diorganyl diselenides promoted intramolecular cyclization of o-alkynyl anilines, as an alternative for the construction of functionalized 3-organoselenyl indoles. The cyclization reactions proceeded smoothly at room temperature in the presence of air giving the 3-organoselenyl indoles in good yields. Additionally, the 3-organoselenyl indoles proved to be quite useful as synthetic intermediates for the construction of more functionalized indole units through a selenium-lithium exchange reaction followed by trapping the lithium intermediate with different electrophiles. © Georg Thieme Verlag Stuttgart New York.

Maciel J.V.,Grande Rio University | Maciel J.V.,Federal University of Santa Maria | Knorr C.L.,Federal University of Santa Maria | Flores E.M.M.,Federal University of Santa Maria | And 4 more authors.
Food Chemistry | Year: 2014

A method based on microwave-induced combustion (MIC) was developed for fish (Engraulis anchoita) digestion and subsequent determination of As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Se, and Zn by inductively coupled plasma mass spectrometry (ICP-MS). A reflux step (5 min) was applied to improve absorption and recovery of analytes. Nitric acid was investigated as absorbing solution and suitable results were achieved using 5 mol L-1 HNO3. Microwave-assisted digestion in closed vessels using concentrated HNO 3 was also evaluated for comparison of results. Both sample preparation methods were considered suitable for sample digestion but MIC was preferable not only because diluted HNO3 can be used as absorbing solution but also because it provides higher efficiency of digestion and also better limits of detection. Accuracy was evaluated by the analysis of certified reference materials (DORM-2 and TORT-2) after MIC digestion with subsequent determination by ICP-MS. Agreement with certified values was better than 94%. © 2013 Elsevier Ltd. All rights reserved.

Burkert C.A.V.,Grande Rio University | Barbosa G.N.O.,University of Campinas | Mazutti M.A.,Federal University of Santa Maria | Maugeri F.,University of Campinas
Process Biochemistry | Year: 2011

This work presents the mathematical modeling of the cephalosporin C (CPC) adsorption process in a fixed-bed column. The application of Particle Swarm Optimization (PSO) algorithm for parameter estimation was first considered, which shows to be a useful tool for parameter estimation in adsorption processes. Modeling and simulation of CPC purification showed a good performance during both estimation and validation step. After this, a central composite rotational design (CCRD) was conceived taking into account both the superficial velocity of liquid and column length as process variables with the responses obtained from the application of the model, which works as a process simulator affording a process answer from a given input. It has been shown that the response surface methodology was an efficient optimization tool, since few simulations were required to find the optimum region for independent variables. © 2011 Elsevier Ltd. All rights reserved.

Kohler M.H.,Federal University of Santa Maria | Da Silva L.B.,Grande Rio University
Chemical Physics Letters | Year: 2016

Equilibrium molecular dynamics simulations were carried out in order to determine the viscosity of water confined into carbon nanotubes. We have found that the viscosity of confined water is about an order of magnitude lower than bulk and increase non-linearly with nanotube diameter. We quantify the influence of density of water upon its viscosity, and observed a strong dependence between both quantities. After analysis of density profiles and diffusion coefficients we conclude that water at high density regime experiences a structural transition resulting in a large increment in viscosity. © 2015 Elsevier B.V. All rights reserved.

Loreto E.L.S.,Federal University of Santa Maria | Loreto E.L.S.,Federal University of Rio Grande do Sul | Zambra F.M.B.,Federal University of Rio Grande do Sul | Ortiz M.F.,Federal University of Rio Grande do Sul | Robe L.J.,Grande Rio University
Molecular Genetics and Genomics | Year: 2012

Genomic searches for P-like transposable elements were performed (1) in silico in the 12 available Drosophila genomes and (2) by PCR using degenerate primers in 21 Neotropical Drosophila species. In silico searches revealed P-like sequences only in Drosophila persimilis and Drosophila willistoni. Sixteen new P-like elements were obtained by PCR. These sequences were added to sequences of previously described P-like elements, and a phylogenetic analysis was performed. The subfamilies of P-elements described in the literature (Canonical, M, O, T, and K) were included in the reconstructed tree, and all were monophyletic. However, we suggest that some subfamilies can be enlarged, other subdivided, and some new subfamilies may be proposed, totalizing eleven subfamilies, most of which contain new P-like sequences. Our analyses support the monophyly of P-like elements in Drosophilidae. We suggest that, once these elements need host-specific factors to be mobilizable, the horizontal transfer (HT) of P-like elements may be inhibited among more distant taxa. Nevertheless, HT among Drosophilidae species appears to be a common phenomenon. © Springer-Verlag 2012.

Zepka L.Q.,Federal University of Santa Maria | Jacob-Lopes E.,Federal University of Pelotas | Goldbeck R.,Grande Rio University | Souza-Soares L.A.,Grande Rio University | Queiroz M.I.,Grande Rio University
Bioresource Technology | Year: 2010

The aim of this research was to evaluate the nutritional characteristics of Aphanothece microscopica Nägeli microalgae developed in the effluent of parboiled rice. The biomass was biologically evaluated by rat growth, during 10 days for nitrogen balance studies and 28 days for blood analysis. The feeding of Aphanothece biomass diets resulted in a nitrogen balance of 1.42 g/rat/day, an apparent biological value of 73.33%, an apparent digestibility of 82.12%, an apparent net protein utilization of 60.21% and a net protein retention of 2.40. Significant differences between the glycemic indices of rats fed with the Aphanothece and those fed with the control diet were not observed. However, the total cholesterol levels in the plasma of rats fed the test diet proved to be significantly lower. These results suggest the use of A. microscopica Nägeli developed in parboiled rice effluent as a potential source of single-cell protein. © 2010 Elsevier Ltd. All rights reserved.

De Oliveira G.A.,Federal University of Paraná | De Oliveira G.A.,French National Institute for Agricultural Research | Bureau S.,French National Institute for Agricultural Research | Bureau S.,University of Avignon | And 5 more authors.
Food Chemistry | Year: 2014

NIR Spectroscopy ability was investigated to assess the fruit structure effect (passion fruit, tomato and apricot) on prediction performance of soluble solids content (SSC) and titratable acidity (TA). Relationships between spectral wavelengths and SSC and TA were evaluated through the application of chemo-metric techniques based on partial least squares (PLS). Good prediction performance was obtained for apricot with correlation coefficients of 0.93 and 0.95 for SSC and TA and root mean square errors of prediction (RMSEP%) of 3.3% and 14.2%, respectively. For the passion fruit and tomato, the prediction models were not satisfactorily accurate due to the high RMSEP. Results showed that NIR technology can be used to evaluate apricot internal quality, however, it was not appropriate to evaluate internal quality in fruits with thick skin, (passion fruit), and/or heterogeneous internal structure (tomato). © 2013 Elsevier Ltd. All rights reserved.

Queiroz M.I.,Grande Rio University | Hornes M.O.,Grande Rio University | Goncalves da Silva Manetti A.,Grande Rio University | Zepka L.Q.,Federal University of Santa Maria | Jacob-Lopes E.,Federal University of Santa Maria
Biosystems Engineering | Year: 2013

The aim was to develop a bioprocess for conversion of wastes of fish processing into single-cell oil and single-cell protein with parallel water reuse under the scope of a biorefinery. The wastes generated by the process were used to support the heterotrophic growth of microalgae simultaneously converting the organic matter, nitrogen, and phosphorus of the wastewater into biomass that is suitable for energy and nutrient production. Chemical treatment, based on coagulation-flocculation-sedimentation, was used to separate the biomass of the wastewater, and membrane microfiltration was used to reclaim water and permit reuse in industrial cooling systems. © 2013.

Cardoso Jr. G.,Federal University of Santa Maria | Mariotto L.,Federal University of Santa Maria
IEEE Transactions on Power Delivery | Year: 2010

A new loss-of-excitation protection based on fuzzy set theory has been presented. It makes use of conventional concepts of loss-of-excitation protection in synchronous generators (i.e., the behavior of internal voltage and apparent impedance trajectory). Instead of crisp values, a fuzzy inference mechanism is applied. To show the effectiveness of the proposed technique, comparisons are made with traditional protection methods by considering different generators sizes. The protection scheme proposed displays a secure and effective high-speed loss-of-excitation detection during power swings. Furthermore, the performance of the proposed method was not affected by generator parameters. © 2010 IEEE.

Dutra M.M.,Grande Rio University | Moriguchi E.H.,University of the Rio dos Sinos Valley | Lampert M.A.,Federal University of Santa Maria | Poli-de-Figueiredo C.E.,Grande Rio University
Revista de Saude Publica | Year: 2011

Objective: To test the predictive validity of the Probability of Repeated Hospital Admissions questionnaire among older adults. Methods: A population-based cohort study with a 6-month follow-up was implemented with 515 non-institutionalized older people (≥60 years) cared for by the Family Health Strategy in the city of Progresso, Southern Brazil, in 2005. Participants answered eight objective questions that were entered in a logistic regression model to estimate the risk of future hospital admission, by risk strata. Survival analysis and the receiver operating characteristics curve were utilized to assess instrument validity. Results: Among participants, 56.1% were women and 10.1% were hospitalized. The high-risk group had a 6.5 times greater frequency of hospitalization in comparison to the low-risk category. Conclusions: The instrument is effective in assessing the risk of hospitalization among older adults attended by the Family Health Program of the National Unified Health Care System.

Cerqueira M.B.R.,Grande Rio University | Guilherme J.R.,Grande Rio University | Caldas S.S.,Grande Rio University | Martins M.L.,Federal University of Santa Maria | And 2 more authors.
Chemosphere | Year: 2014

A modified version of the QuEChERS method has been evaluated for the determination of 21 pharmaceuticals and 6 personal care products (PPCPs) in drinking-water sludge samples by employing ultra high liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The performance of the method was evaluated through linearity, recovery, precision (intra-day), method detection and quantification limits (MDL and MQL) and matrix effect. The calibration curves prepared in acetonitrile and in the matrix extract showed a correlation coefficient ranging from 0.98 to 0.99. MQLs values were on the ngg-1 order of magnitude for most compounds. Recoveries between 50% and 93% were reached with RSDs lower than 10% for most compounds. Matrix effect was almost absent with values lower than 16% for 93% of the compounds. By coupling a quick and simple extraction called QuEChERS with the UPLC-MS/MS analysis, a method that is both selective and sensitive was obtained. This methodology was successfully applied to real samples and caffeine and benzophenone-3 were detected in ngg-1 levels. © 2014 Elsevier Ltd.

Stein A.L.,Federal University of Santa Maria | Da Rocha J.,Federal University of Santa Maria | Menezes P.H.,Federal University of Pernambuco | Zeni G.,Federal University of Pernambuco
European Journal of Organic Chemistry | Year: 2010

We present here our results on the electrophilic cyclization reaction of 3-alkynylthiophenes with different electrophiles such as I2, ICl, and PhSeBr. The cyclization reaction proceeded cleanly under mild reaction conditions, giving fused 4-iodoselenophene[2,3-b]thiophenes in excellent yields. In addition, the obtained chalcogenophenes were readily transformed into more complex products through palladium- or copper-catalyzed cross-coupling reactions with thiols, boronic acids, and organozinc reagents. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA,.

Schwab R.S.,Federal University of Santa Maria | Soares L.C.,Federal University of Santa Maria | Dornelles L.,Federal University of Santa Maria | Rodrigues O.E.D.,Federal University of Santa Maria | And 3 more authors.
European Journal of Organic Chemistry | Year: 2010

A new series of chiral chalcogen peptides were synthesized from, inexpensive and commercially available starting materials. The synthesized compounds were tested as catalysts in the enantioselective arylation of aldehydes by using aryloronic acids as the aryl source. The desired diarylmethanols were obtained in excellent yields and with enantioselectivities up to 91% ee. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mesko M.F.,Federal University of Pelotas | Pereira J.S.F.,Federal University of Santa Maria | Moraes D.P.,Federal University of Santa Maria | Barln J.S.,Federal University of Santa Maria | And 5 more authors.
Analytical Chemistry | Year: 2010

A procedure for sample digestion based on focused microwave-induced combustion (FMIC) is proposed. This system was developed using a commercial focused microwave oven with a lab-made quartz sample holder and a modified glass vessel. Oxygen flow was used to start and support the combustion. A botanical sample was used to evaluate the operational conditions for further Al, Ba, Ca, Fe, Mg, Mn, Sr, and Zn determination by inductively coupled plasma optical emission spectrometry. Pelletized samples were positioned on the quartz holder, and 50 μL of 6 mol L -1 NH 4NO 3 solution was added as igniter. Combustion was completed in less than 2 min, and the temperature was higher than 950 °C. The use of a reflux step, the position of sample holder inside the vessel, sample mass, ignition and combustion time, oxygen flow rate, and condenser type were evaluated. Results were compared with those obtained by focused microwave-assisted wet digestion and by high pressure microwave-assisted wet digestion. Agreement of 95103% was obtained for certified reference materials digested by FMIC (reflux step with 10 mL of 4 mol L -1 HNO 3). With the proposed procedure, a complete sample decomposition (residual carbon content lower than 0.5%) was achieved with low consumption of reagents as only 10 mL of diluted nitric acid was necessary. Low relative standard deviation (lower than 3.8%) was observed and high amount of sample (up to 1500 mg) could be digested that allowed lower limits of detection. © 2010 American Chemical Society.

Soares B.M.,Grande Rio University | Vieira A.A.,Grande Rio University | Lemoes J.S.,Grande Rio University | Santos C.M.M.,Federal University of Santa Maria | And 4 more authors.
Bioresource Technology | Year: 2012

This work reports, for the first time, the determination of major and trace elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Se, Sn, Sr, Ti, Tl, U, V, and Zn) in the fractions of the synthesis of fatty acid methyl esters (FAMEs). These include fresh microalgae, residual biomass, lipid fraction, crude FAMEs, insoluble fraction and purified FAMEs from microalgae Chlorella sp. A microwave-assisted digestion procedure in closed vessels was applied for sample digestion and subsequent element determination by inductively coupled plasma-based techniques. The proposed method was suitable for the multielement determination in FAMEs and its fractions obtained from microalgae. The element concentration was compared with results found in the literature and a careful discussion about the use of residual biomass for different applications was performed. © 2012 Elsevier Ltd.

Bertuol D.A.,Federal University of Santa Maria | Toniasso C.,Federal University of Santa Maria | Jimenez B.M.,Federal University of Santa Maria | Meili L.,Federal University of Alagoas | And 3 more authors.
Journal of Power Sources | Year: 2015

The growing environmental concern, associated with the continuous increase in electronic equipment production, has induced the development of new technologies to recycle the large number of spent batteries generated in recent years. The amount of spent lithiumeion batteries (LIBs) tends to grow over the next years. These batteries are composed by valuable metals, such as Li, Co, Cu and Al, which can be recovered. Thus, the present work is carried out in two main steps: In the first step, a characterization of the LIBs is performed. Batteries from different brands and models are dismantled and their components characterized regarding to the chemical composition and main phases. In the second step, a sample of LIBs is shredded and the different materials present are separated by spouted bed elutriation. The results show that spouted bed elutriation is a simple and inexpensive way to obtain the separation of the different materials (polymers, metals, active electrode materials) present in spent LIBs. © 2014 Elsevier B.V. All rights reserved.

Busanello A.,Federal University of Santa Maria | Barbosa N.B.V.,Federal University of Santa Maria
Behavioural Pharmacology | Year: 2011

Reserpine treatment is a putative animal model of orofacial dyskinesia, tremor, and Parkinsonism. Here, we examined the effects of resveratrol, a polyphenol with neuroprotective properties primarily contained in red grapes and red wine, in an animal model of vacuous chewing movements (VCMs) induced by treatment with reserpine. Mice were treated with reserpine (1 mg/kg, subcutaneously on days 1 and 3) and/or resveratrol (5 mg/kg, intraperitoneally 3 consecutive days). VCM, locomotor, and exploratory performance were evaluated. Reserpine treatment produced an increase in VCM intensity, which was significantly reduced by resveratrol co-treatment. Reserpine also decreased locomotor and exploratory activity in the open field test. However, resveratrol co-treatment was not able to protect against these effects. The data suggest that resveratrol could be a promising pharmacological tool for studying VCM in rodents. However, further investigations are needed to understand the exact mechanisms involved in the neuroprotective effects of resveratrol. © 2011 Wolters Kluwer Health Lippincott Williams & Wilkins.

Battistel O.A.,Federal University of Santa Maria | Fonseca M.V.S.,Brazilian Center for Research in Physics (CBPF) | Dallabona G.,Federal University of Lavras
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

An explicit and detailed investigation about the two-dimensional single axial-vector (AVV) triangle is performed. Such a perturbative amplitude is related to the anomalous axial-vector (AV) one through contractions with external momenta. Given this fact, before considering such a triangle we must give a clear point of view for the AV amplitude. Such a point of view is constructed within the context of an alternative strategy to handle the divergences typical of perturbative solutions of quantum field theory. In this procedure all amplitudes in all theories, formulated in odd and even space-time dimensions, renormalizable or not, are treated in an absolutely identical way. The ambiguities are automatically eliminated and the symmetry relations preserved. The well-known divergent anomalous amplitudes are correctly described, in a predictive scenario. After performing, in a very detailed way, all the calculations involved we conclude that the same phenomenon occurring in the AV amplitude is also present in the finite AVV triangle. The conclusion gives support to the thesis that the phenomenon is present in all pseudoamplitudes in a chain where the divergent AV one is only the most simple structure. The same must occur in all even space-time dimensions. In particular, the single and triple four-dimensional box amplitudes must exhibit anomalies too. A conclusive investigation is allowed due to the special features of the adopted procedure where regularization is completely avoided and an adequate systematization for the finite parts is introduced. © 2012 American Physical Society.

Campagnol P.C.B.,University of Campinas | Santos B.A.D.,University of Campinas | Morgano M.A.,Institute Tecnologia Of Alimentos | Terra N.N.,Federal University of Santa Maria | Pollonio M.A.R.,University of Campinas
Meat Science | Year: 2011

The effects of 50% replacement of NaCl by KCl and addition of the amino acids lysine and taurine and the 5'-ribonucleotide disodium inosinate and disodium guanylate on some sensory and physicochemical parameters of fermented cooked sausages were evaluated. The partial replacement of NaCl by KCl did not alter the manufacturing process; however, defects in the sensory quality were detected. Lysine at a concentration of 0.313% and a mixture of taurine (750. mg/kg) with disodium inosinate (300. mg/kg) and disodium guanylate (300. mg/kg) reduced the sensory defects caused by KCl, allowing the fermented cooked sausages to be elaborated with reduced sodium content and high sensory quality. © 2010 The American Meat Science Association.

Flores E.M.M.,Federal University of Santa Maria | Muller E.I.,Federal University of Santa Maria | Duarte F.A.,Grande Rio University | Grinberg P.,National Research Council Canada | Sturgeon R.E.,National Research Council Canada
Analytical Chemistry | Year: 2013

An effective approach to the digestion of fluoropolymers for the determination of Ag, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, and Ni impurities has been developed using microwave-induced combustion (MIC) in closed quartz vessels pressurized with oxygen. Samples that were examined included the following: polytetrafluorethylene (PTFE); polytetrafluoroethylene with an additional modifier, perfluoropropylvinylether (PTFE-TFM); and fluorinated ethylene propylene (FEP). A quartz device was used as a sample holder, and the influence of the absorber solution was evaluated. Determination of trace elements was performed by inductively coupled plasma-optical emission and mass spectrometry. Neutron activation analysis (NAA) was used for validation purposes. Results were also compared to those obtained using microwave-assisted acid extraction in high-pressure closed systems. Dilute nitric acid (5 mol L-1), which was selected as the absorbing medium, was used to reflux the sample for 5 min after the combustion. Using these conditions, agreement for all analytes was better than 98% when compared to values determined by NAA. The residual carbon content in the digests was lower than 1%, illustrating the high efficiency of the method. Up to 8 samples could be digested within 30 min using MIC, providing a suitable throughput, taking into account the inertness of such samples. © 2012 American Chemical Society.

de Mello C.F.,Federal University of Santa Maria
Journal of Pain | Year: 2010

Oxidative stress markers are thought to be related to nociception. Because thiolic compounds are important antioxidants, we investigated the relationship between thiols, endogenous or exogenous, and nociception. Systemic or spinal, but not peripheral, administration of the exogenous thiolic compound N-acetyl-L-cysteine (NAC) reduced nociception induced by intraplantar capsaicin injection. Moreover, we detected an increase in lipid peroxidation and 3-nitrotyrosine and a decrease in nonprotein thiolic levels in the lumbar spinal cord of capsaicin-injected animals. All these effects were prevented by NAC treatment (i.p. and i.t.). Our findings confirm a role for the spinal cord in NAC actions because systemic NAC administration also reduced the nociception trigged by intrathecal injection of capsaicin. Moreover, adjuvant-induced arthritis, but not paw incision, also -decreases nonprotein thiol levels in the spinal cord. Similarly, NAC produced antinociception in adjuvant-treated animals, but not in paw-incised animals. Finally, we investigated the role of endogenous thiol compounds in the nociceptive process administrating buthionine-suphoxamine (BSO), an inhibitor of glutathione-synthesis. Intrathecal BSO treatment decreased nonprotein thiol levels in the spinal cord, as well as induced mechanical allodynia and chemical and thermal hyperalgesia. In conclusion, our results indicate a critical role for nonprotein thiols in nociception at the level of the spinal cord. Perspective: The results presented here indicate that the loss of nonprotein thiols in the spinal cord is involved in pain development. Therefore, the administration of thiolic compounds or other strategies allow thiol levels to be maintained and could be a beneficial action in the therapy of painful conditions. © 2010 American Pain Society.

Vieira R.P.,Federal University of Santa Maria | Gastaldini C.C.,Federal University of Pampa | Azzolin R.Z.,Grande Rio University | Grundling H.A.,Federal University of Santa Maria
IEEE Transactions on Industrial Electronics | Year: 2014

This paper presents a rotor speed observer for induction-machine drives based on a sliding-mode approach and magnetizing current estimation. The back electromotive force (EMF) is calculated from the stator current and the stator voltage signals. The magnetizing currents are obtained from the back EMF. A theorem which gives the rotor speed estimate in the continuous-time domain is formulated using the magnetizing current estimation. The stability analysis is achieved based on the Lyapunov approach. Moreover, the discrete-time approach of the method is discussed, and a theorem for the discrete-time implementation is proposed. The limits that ensure the system stability for the switching gains and for the observer gain are discussed. This paper shows that the limits for the gains of the discrete-time algorithm are different from the limits for the gains of the continuous-time algorithm. Simulation results are presented to validate the theoretical analysis. In addition, experimental results based on a fixed-point digital signal processor (DSP) platform (DSP TMS320F2812) demonstrate the performance of the proposed scheme. © 1982-2012 IEEE.

Bizzi C.A.,Federal University of Santa Maria | Flores E.L.M.,Federal Technological University of Paraná | Nobrega J.A.,Federal University of São Carlos | Oliveira J.S.S.,Federal University of Santa Maria | And 2 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2014

Many efforts have been made in order to reduce the amount of reagents and waste produced in analytical laboratories. However, suitable digestion efficiency must be considered, and depending on the sample preparation procedure, incomplete digestion can result in severe matrix effects during analysis by spectrometric techniques such as ICP OES and ICP-MS. In the present work a procedure based on the use of H2O2 was developed in order to minimize the consumption of HNO3 without decreasing the efficiency of digestion. Although H2O2 has been used combined with HNO3 for sample digestion, its role is still not completely elucidated even as its action combined with O2 in pressurized systems. The performance obtained using H2O2 was similar to that observed when adding O2 to the reaction vessel, driving the better understanding of the role of H2O2 in closed digestion procedures. Digestion using H2O2 allowed the use of HNO3 solutions as diluted as 1 mol L-1 to digest sample masses of biological materials as high as 500 mg. The proposed procedure allowed a reduction of up to 14 and 9.3-fold in the HNO3 amount normally used in whole milk powder and bovine liver digestions, respectively, without decreasing the digestion efficiency. Calcium, Cu, Fe, K, Mg, Mn, Mo, Na, and Zn were determined by ICP OES, while Cd, Co, and Pb were determined by ICP-MS. Using diluted HNO3 solution low blank values were obtained resulting in relatively lower limits of detection and relative standard deviations. The accuracy was evaluated by using certified reference materials of milk powder and bovine liver (agreement was better than 95% to certified values for all evaluated analytes). © 2014 The Royal Society of Chemistry.

Rodrigues L.F.,Federal University of Santa Maria | Rodrigues L.F.,Grande Rio University | Mattos J.C.P.,Federal University of Santa Maria | Bolzan R.C.,Federal University of Santa Maria | And 2 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2014

The concentration of Fe, Mg, Mn and Na at ultra-trace levels was determined in polymeric diphenylmethane dianiline, a raw material for polyurethane production, by direct sampling graphite furnace atomic absorption spectrometry (DS-GFAAS). A Zeeman-effect background correction system operated in 2-field or 3-field dynamic modes was used. Calibration was carried out using aqueous reference solutions and a sample mass between 0.5 and 35 mg was used. The relative standard deviation was calculated after successive measurements (number of replicates was 14 to 23 throughout the range of sample mass) and was below 15%. Blank values obtained using DS-GFAAS were lower than those obtained with other evaluated procedures. The accuracy was evaluated by comparison of the results with those obtained by inductively coupled plasma optical emission spectrometry (ICP-OES) after microwave assisted digestion (MAD) in closed vessels and microwave-induced combustion (MIC). There were no statistical differences (confidence level 95%) between the results obtained for the analysis of all the analytes by DS-GFAAS and those obtained by ICP-OES after MAD and MIC. The limits of detection were considerably lower (0.06 to 0.27 ng g -1) in comparison with those obtained by ICP-OES after MAD (35 to 5443 ng g-1) and MIC (12 to 4890 ng g-1). © 2014 The Royal Society of Chemistry.

Da Cunha Amaral H.L.,Federal University of Santa Maria | Bergmann F.B.,Grande Rio University | Dos Santos P.R.S.,CEMAVE | Kruger R.F.,Federal University of Pelotas | Graciolli G.,Federal University of Mato Grosso do Sul
Parasitology Research | Year: 2013

This study was aimed at describing the community of arthropod ectoparasites associated with sympatric populations of Turdus amaurochalinus and Turdus rufiventris and analyzing the aggregation patterns of the chewing lice species, during reproductive and nonreproductive periods, of both Turdus species in three areas of the Atlantic forest in southern Rio Grande do Sul state (RS), Brazil. Altogether, we captured 36 specimens of T. amaurochalinus and 53 specimens of T. rufiventris. We identified two families of chewing lice, Menoponidae and Philopteridae, with Myrsidea and Brueelia as the most prevalent and abundant on both host birds. The lowest aggregation levels of chewing lice Myrsidea and Brueelia occurred during the reproductive period of both host species, suggesting a reproductive synchronization and a dispersion period. The most prevalent feather mite on T. amaurochalinus was Proctophyllodes weigoldi, and on T. rufiventris, Trouessartia serrana. Analges sp. and Pteronyssoides sp. were not observed on T. rufiventris. We identified three species of ticks; Ixodes auritulus was the most prevalent and abundant on the birds. Ornithoica vicina was the only hippoboscid fly collected, and only on T. amaurochalinus. The richness of ectoparasites was greater on T. amaurochalinus than on T. rufiventris. For T. amaurochalinus, the mean richness was lesser in winter compared to spring and autumn; however, we observed no variation in the mean richness of ectoparasites for T. rufiventris during the same seasons. © 2012 Springer-Verlag Berlin Heidelberg.

Moraes C.C.,Federal University of Pampa | Mazutti M.A.,Federal University of Santa Maria | Maugeri F.,University of Campinas | Kalil S.J.,Grande Rio University
Journal of Chromatography A | Year: 2013

This work is focused on the experimental evaluation and mathematical modeling of ion exchange expanded-bed chromatography for the purification of C-phycocyanin from crude fermentative broth containing Spirulina platensis cells. Experiments were carried out in different expansion degree to evaluate the process performance. The experimental breakthrough curves were used to estimate the mass transfer and kinetics parameters of the proposed model, using the Particle Swarm Optimization algorithm (PSO). The proposed model satisfactorily fitted the experimental data. The results from the model application pointed out that the increase in the initial bed height does not influence the process efficiency, however enables the operation of expanded-bed column at high volumetric flow rates, improving the productivity. It was also shown that the use of mathematical modeling was a good and promising tool for the optimization of chromatographic processes. © 2013 Elsevier B.V.

Barancelli D.A.,Federal University of Santa Maria | Acker C.I.,Federal University of Santa Maria | Menezes P.H.,Federal University of Pernambuco | Zeni G.,Federal University of Santa Maria
Organic and Biomolecular Chemistry | Year: 2011

We herein described the synthesis of several 3-benzyl-2,5-diarylselenophene derivatives in moderate to good yields using (Z)-benzylselenoenynes as starting material in carbocyclization reactions. The reactions were carried out under mild conditions using only t-BuOK as base, in the complete absence of transition metals or additives. The cyclized 3-benzyl-2,5-diarylselenophenes obtained in the current protocol appear highly promising and attractive intermediates for the synthesis of polysubstituted selenophenes. For instance, 3-benzyl-2,5-diphenylselenophene was treated with Br2 provided the corresponding 3-benzyl-4-bromo-2,5-diphenylselenophene in high yield. 4-Bromoselenophene derivative was applied as substrate in the palladium catalyzed cross-coupling reactions with boronic acids to give the Suzuki type products in excellent yields. © The Royal Society of Chemistry 2011.

Scaravelli R.C.B.,Federal University of Santa Maria | Dazzi R.L.,Federal University of Santa Maria | Giacomelli F.C.,Federal University of ABC | Giacomelli C.,Federal University of Santa Maria | Schmidt V.,Federal University of Santa Maria
Journal of Colloid and Interface Science | Year: 2013

The single-step/single-phase synthesis of hybrid organic-inorganic core-shell gold nanoparticles (AuNPs), facilitated by amino-functionalized amphiphilic block copolymers that simultaneously play the roles of reductant and stabilizer, was investigated in this study. Experiments were devised with emphasis on the pH-responsive poly(ethylene oxide)- b-poly(2,3-dihydroxypropyl methacrylate)- b-poly[2-(diisopropylamino)ethyl methacrylate] triblock copolymer, which allows direct chemical cross-linking of the micellar structures to be performed. The polymer structure-reactivity relationship associated with the AuNP formation was established using a set of six structurally related macromolecules. AuNP formation was dependent on the aqueous dissociation equilibrium involving tertiary amino groups, the Au(III) speciation, and electrochemical redox potentials. The effects of these parameters on the synthesis of AuNPs change as the solution pH is increased from pH 3.3 (molecularly dissolved polymer chains; no AuNP formation) to 6.8 or higher (polymer chains self-assembled into spherical micelles; stable gold sols are produced), and Au(III) reduction potentials shift toward the cathodic region while the oxidation potential of deprotonated amino groups decreases. Sigmoidal nanoparticle growth kinetics was observed in all cases after a characteristic induction period. Stable, well-defined, uniform polymer-coated gold colloids with localized surface plasmon resonance centered at 530. nm can be conveniently produced in one-pot, two-reactant, no work-up reactions when the stoichiometry is [N]/[Au] = 3.5-25.0. © 2013 Elsevier Inc.

Bayer F.M.,Federal University of Santa Maria | Cintra R.J.,Federal University of Pernambuco | Cintra R.J.,University of Akron
Electronics Letters | Year: 2012

A low-complexity 8-point orthogonal approximate discrete cosine transform (DCT) is introduced. The proposed transform requires no multiplications or bit-shift operations. The derived fast algorithm requires only 14 additions, less than any existing DCT approximation. Moreover, in several image compression scenarios, the proposed transform could outperform the well-known signed DCT, as well as state-of-the-art algorithms. © 2012 The Institution of Engineering and Technology.

Potluri U.S.,University of Akron | Madanayake A.,University of Akron | Cintra R.J.,Federal University of Pernambuco | Bayer F.M.,Federal University of Santa Maria | And 2 more authors.
IEEE Transactions on Circuits and Systems I: Regular Papers | Year: 2014

Video processing systems such as HEVC requiring low energy consumption needed for the multimedia market has lead to extensive development in fast algorithms for the efficient approximation of 2-D DCT transforms. The DCT is employed in a multitude of compression standards due to its remarkable energy compaction properties. Multiplier-free approximate DCT transforms have been proposed that offer superior compression performance at very low circuit complexity. Such approximations can be realized in digital VLSI hardware using additions and subtractions only, leading to significant reductions in chip area and power consumption compared to conventional DCTs and integer transforms. In this paper, we introduce a novel 8-point DCT approximation that requires only 14 addition operations and no multiplications. The proposed transform possesses low computational complexity and is compared to state-of-the-art DCT approximations in terms of both algorithm complexity and peak signal-to-noise ratio. The proposed DCT approximation is a candidate for reconfigurable video standards such as HEVC. The proposed transform and several other DCT approximations are mapped to systolic-array digital architectures and physically realized as digital prototype circuits using FPGA technology and mapped to 45 nm CMOS technology. © 2014 IEEE.

Dotto G.L.,Federal University of Santa Maria | Pinto L.A.A.,Grande Rio University | Hachicha M.A.,University of Monastir | Knani S.,University of Monastir
Food Chemistry | Year: 2014

In this work, statistical physics treatment was employed to study the adsorption of food dyes onto chitosan films, in order to obtain new physicochemical interpretations at molecular level. Experimental equilibrium curves were obtained for the adsorption of four dyes (FD&C red 2, FD&C yellow 5, FD&C blue 2, Acid Red 51) at different temperatures (298, 313 and 328 K). A statistical physics formula was used to interpret these curves, and the parameters such as, number of adsorbed dye molecules per site (n), anchorage number (n′), receptor sites density (NM), adsorbed quantity at saturation (Nasat), steric hindrance (τ), concentration at half saturation (c1/2) and molar adsorption energy (ΔEa) were estimated. The relation of the above mentioned parameters with the chemical structure of the dyes and temperature was evaluated and interpreted. © 2014 Elsevier Ltd. All rights reserved.

The performance of beef calves submitted to two weaning ages (early weaning, at an average age of 80 days; conventional weaning, at an average age of 152 days) was evaluated. One hundred and five Braford calves born in 2004 and 2005, after weaning, were kept on pastures cultivated with pearl millet (Pennisetum americanum) in the first and second summer and, in winter/spring, they were kept on pastures with oat and ryegrass (Avena strigosa Schreb + Lolium multiflorum Lam). Body weight (BW), average daily weight gain (ADWG) and body condition (BC) were evaluated. There was a significant interaction among age at weaning and year for daily weight gain for early weaning as well as for conventional weaning on oat and ryegrass pastures. In the period between the two weaning ages, the daily weight gain in early weaning was higher in 2004 than in 2005 (0.499 vs 0.468 kg, respectively) and for early weaning, higher daily weight gain occurred in 2005 (0.493 vs. 0.631 kg, respectively). On oat and ryegrass pasture, average daily weight gain for early weaned animals in 2004 (0.666 kg) was lower than in 2005 (0.760 kg), however, there was no difference among years for conventional weaned animals (0.720 and 0.723 kg, respectively). During second summer periods, average daily weight gain did not differ among early and conventional weaned animals. Weight of early weaned animals (158.2 kg) was higher than conventional weaned animals (147.7 kg) in the beginning of winter grazing; however, it did not differ at the end. In the end of the summer, when calves were 15-16 months of age, body weight was similar among early weaned (340.1 and 4.14 points) and conventional (332.8 kg and 4.15 points) weaned animals. Final body condition, in 2004, was higher (4.34) than in 2005 (3.96 points). Calves weaned at 80 days of age and adequately fed present similar development as those weaned at 152 days of age, achieving development and finishing conditions to be slaughtered for specific markets at 15-16 months of age. © 2011 Sociedade Brasileira de Zootecnia.

The study was structured to determine the necessary factors, from the point of view of chemical control of foliar diseases, to obtain high quality wheat for bread production. The experiment in randomized blocks with six replicates tried to clarify the interaction between twelve cultivars and seven fungicide application programs, as well as its implications in the yield and quality of wheat grains. The results showed that the effects provided by fungicides in disease control, and their direct effects on the physiology of wheat plants, were decisive factors for obtaining highquality wheat. The results also showed that diseases compromise the remobilization of nitrogen from leaves to grains. The differences between strobilurins and triazoles were evident in the control of leaf spot and leaf rust, in which triazole fungicides were more effective in controlling the leaf spot complex, when compared to strobilurins. However, effective control of wheat leaf rust was provided by strobilurins. The phenological stages of elongation and emission of spikes are critical times for the chemical control of leaf spot under conditions of monoculture. In addition, the fungicide application after flowering is essential for the appropriate management of leaf rust.

Both C.,Federal University of Rio Grande do Sul | Both C.,Grande Rio University | Cechin S.Z.,Federal University of Santa Maria | Melo A.S.,Federal University of Rio Grande do Sul | And 2 more authors.
Austral Ecology | Year: 2011

The community structure of pond systems is affected by resource competition, predation and degree of permanence of water. Here we evaluated the effect of the permanence-predation gradient in ponds on species richness and guild composition of tadpoles. The study was carried out at Caçapava do Sul in southern Brazil. Tadpoles and invertebrate predators were sampled in 38 ponds of different sizes and degrees of permanence. The collections were carried out twice, in spring 2007 and summer 2008. We ordinated guild composition in ponds in a single dimension through a non-metric multidimensional scaling. The relationships between tadpole richness and guild composition with environmental descriptors were tested through multiple regression. The species were classified into six guilds. Species richness increased with the abundance of predators and the mean water depth in summer. The ordination of guild composition was explained by permanence and mean depth in summer. Our results indicated a clear guild replacement through a permanence-depth gradient, confirming permanence as an important environmental filter. Therefore, most rich ponds would not contain species from all groups, and even very small, shallow and ephemeral ponds are important, given that some species groups are exclusive to such habitats. © 2010 The Authors. Journal compilation © 2010 Ecological Society of Australia.

Copetti M.V.,Federal University of Santa Maria | Pereira J.L.,University of Campinas | Iamanaka B.T.,Institute Tecnologia Of Alimentos | Pitt J.I.,CSIRO | Taniwaki M.H.,Institute Tecnologia Of Alimentos
International Journal of Food Microbiology | Year: 2010

This study investigated the occurrence of fungi with the potential to produce ochratoxin A (OTA), and the occurrence of OTA, in Brazilian cocoa beans. Two hundred and twenty two samples of cocoa were evaluated, taken at various stages of fermentation, drying and storage. Samples were collected from Bahia, the main cocoa producing region in Brazil. Fungi with the potential to produce OTA were isolated by direct plating of cocoa beans on Dichloran 18% Glycerol agar after surface disinfection, and identified by standard techniques. The ability of the fungi to produce OTA was estimated using the agar plug technique and TLC. The presence of OTA in cocoa samples was determined by HPLC after immunoaffinity column clean up. The most common ochratoxigenic species found were Aspergillus carbonarius and A. niger aggregate. , with lower numbers of A. melleus, A. westerdijkiae and Av. ochraceus. A considerable increase in the numbers of these species was observed during drying and storage. OTA was found at all stages of cocoa processing, with the major incidence during drying and storage. The OTA levels found were in general low and there was a strong positive correlation between the presence of A. carbonarius and OTA contamination in the beans. © 2010 Elsevier B.V.

Specht L.,Federal University of Santa Maria | Khatchatourian O.,Grande Rio University
International Journal of Pavement Engineering | Year: 2014

The viscosity of binder is of great importance during the handling, mixing, application and compaction of asphalt in highway surfacing. This paper presents experimental data and the application of artificial intelligence techniques (statistics, artificial neural networks (ANNs) and fuzzy logic) to modelling of apparent viscosity in asphalt-rubber binders. The binders were prepared in the laboratory by varying the rubber content (RC), rubber particle size, duration and temperature of mixture in conformity with a statistical design plan. Multi-factorial analysis of variance showed that the RC has a major influence on the viscosity observed for the considered interval of parameters variation. When only limited experimental data of design matrix are available for modelling, the fuzzy logic model is the best model to be used. In addition, the combined use of ANN and multiple regression analysis improved the characteristics of the neural network. © 2014 Taylor & Francis.

Copetti M.V.,Federal University of Santa Maria | Iamanaka B.T.,Institute Tecnologia Of Alimentos | Pitt J.I.,CSIRO | Taniwaki M.H.,Institute Tecnologia Of Alimentos
International Journal of Food Microbiology | Year: 2014

Cocoa is an important crop, as it is the raw material from which chocolate is manufactured. It is grown mainly in West Africa although significant quantities also come from Asia and Central and South America. Primary processing is carried out on the farm, and the flavour of chocolate starts to develop at that time. Freshly harvested pods are opened, the beans, piled in heaps or wooden boxes, are fermented naturally by yeasts and bacteria, then dried in the sun on wooden platforms or sometimes on cement or on the ground, where a gradual reduction in moisture content inhibits microbial growth. Beans are then bagged and marketed. In processing plants, the dried fermented beans are roasted, shelled and ground, then two distinct processes are used, to produce powdered cocoa or chocolate. Filamentous fungi may contaminate many stages in cocoa processing, and poor practices may have a strong influence on the quality of the beans. Apart from causing spoilage, filamentous fungi may also produce aflatoxins and ochratoxin A. This review deals with the growth of fungal species and formation of mycotoxins during the various steps in cocoa processing, as well as reduction of these contaminants by good processing practices. Methodologies for fungal and mycotoxin detection and quantification are discussed while current data about dietary exposure and regulation are also presented. © 2014 .

Morais C.V.,Grande Rio University | Lazo M.J.,Grande Rio University | Zimmer F.M.,Federal University of Santa Maria | Magalhaes S.G.,Federal University of Fluminense
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2012

The present work studies the Ghatak-Sherrington (GS) model in the presence of a magnetic random field (RF). Previous results obtained from the GS model without a RF suggest that disorder and frustration are the key ingredients to produce spontaneous inverse freezing (IF). However, in this model, the effects of disorder and frustration always appear combined. In that sense, the introduction of RF allows us to study the IF under the effects of a disorder which is not a source of frustration. The problem is solved within the one step replica symmetry approximation. The results show that the first order transition between the spin glass and the paramagnetic phases, which is related to the IF for a certain range of crystal field D, is gradually suppressed when the RF is increased. © 2012 American Physical Society.

Jorge M.B.,Grande Rio University | Loro V.L.,Federal University of Santa Maria | Bianchini A.,Grande Rio University | Wood C.M.,McMaster University | Gillis P.L.,Environment Canada
Aquatic Toxicology | Year: 2013

Several studies have indicated that the early life stages of freshwater mussels are among the most sensitive aquatic organisms to inorganic chemicals, including copper. However, little is known about the toxic mode of action and sub-lethal effects of copper exposure in this group of imperiled animals. In this study, the physiological effects of long-term copper exposure (survival, growth, copper bioaccumulation, whole-body ion content, oxygen consumption, filtration rate, ATPase activities, and biomarkers of oxidative stress) were evaluated in juvenile (6 month old) mussels (Lampsilis siliquoidea). The mussels' recovery capacity and their ability to withstand further acute copper challenge were also evaluated in secondary experiments following the 28 day exposure by assessing survival, copper bioaccumulation and whole-body ion content. Mussels chronically exposed to 2 and 12μg Cu/L showed significantly higher mortality than those held under control conditions (mortality 20.9, 69.9 and 12.5%, respectively), indicating that juvenile L. siliquoidea is underprotected by the U.S. Environmental Protection Agency (USEPA) biotic ligand model (BLM)-derived chronic water quality criteria (WQC) (2.18μg Cu/L) and the hardness-derived USEPA WQC (12.16μg Cu/L). Soft tissue copper burden increased equally for both copper exposures, suggesting that chronic toxicity is not associated with copper bioaccumulation. Several physiological disturbances were also observed during chronic copper exposure. Most relevant was a decrease in whole-body sodium content paralleled by an inhibition of Na+ K+-ATPase activity, indicating a metal-induced ionoregulatory disturbance. Filtration and oxygen consumption rates were also affected. Redox parameters (reactive oxygen production, antioxidant capacity against peroxyl radicals, glutathione-S-transferase (GST) activity, and glutathione (GSH) concentration) did not show clear responses, but membrane damage as lipid peroxidation (LPO) was observed in both copper exposures. Mussels previously held in control conditions or pre-exposed to 2μg dissolved Cu/L were able to maintain their ionic homeostasis and did not experience mortality after the 4-d recovery period. In contrast, those previously exposed to 12μg dissolved Cu/L exhibited 50% mortality indicating that they had already reached a 'point of no return'. Pre-exposure to copper did not influence mussel response to the copper challenge test. As observed for the chronic exposure, mortality of mussels held in the absence of copper and submitted to the challenge test was also associated with an ionoregulatory disturbance. These results indicate that ionoregulatory disruption in freshwater mussels chronically exposed to copper is the main mechanism of toxicity and that redox parameters do not appear to be useful as indicators of sub-lethal copper toxicity in these animals. © 2012 Elsevier B.V.

Dotto G.L.,Federal University of Santa Maria | Vieira M.L.G.,Grande Rio University | Pinto L.A.A.,Grande Rio University
LWT - Food Science and Technology | Year: 2015

Chitosan solutions were used to extend the microbiological shelf life of papaya fruits during storage at room temperature. The fruits were coated using different chitosans (molecular weights of 150 or 300 kDa) and, stored for 20 days under ambient conditions. Evolution curves of mesophilic bacteria, yeasts and molds on papaya fruits during the storage period were constructed for coated and uncoated samples. These curves were represented by the Gompertz model, in order to estimate the shelf life of papaya fruits. The results showed that the 150 kDa chitosan solution was more adequate to preserve the papaya fruits. After 10 days of storage, the Log (CFU/g) of mesophilic bacteria and yeasts and molds were, respectively, 1.3 and 2 times lowest for coated fruits. The use of 150 kDa chitosan solutions extended in about 4-7 days the shelf life of papaya fruits, during the storage at room temperature. © 2015 Elsevier Ltd.

Cintra R.J.,Federal University of Pernambuco | Cintra R.J.,University of Akron | Bayer F.M.,Federal University of Santa Maria | Tablada C.J.,Federal University of Pernambuco
Signal Processing | Year: 2014

The discrete cosine transform (DCT) is a central mathematical operation in several digital signal processing methods and image/video standards. In this paper, we propose a collection of twelve approximations for the 8-point DCT based on integer functions. Considered functions include: the floor, ceiling, truncation, and rounding-off functions. Sought approximations are required to meet the following specific criteria: (i) very low arithmetic complexity, (ii) orthogonality or quasi-orthogonality, and (iii) low-complexity inversion. By varying a scaling parameter, approximations could be systematically obtained and several existing approximations were identified as particular cases of the proposed methodology. Particular cases include the signed DCT and the rounded DCT. Four new quasi-orthogonal approximations were introduced and their practical relevance was demonstrated. All approximations were given fast algorithms based on matrix factorization methods. Proposed approximations are multiplierless; their computation requires only additions and bit-shifting operations. Additive complexity ranged from 18 to 24 additions. Obtained approximations were compared with the exact DCT and assessed in the context of JPEG-like image compression. As quality assessment measures, we considered the peak signal-to-noise ratio and the structural similarity index. Because its low-complexity and good performance properties, the proposed approximations are suitable for hardware implementation in dedicated architectures. © 2013 Elsevier B.V.

Soares B.M.,Grande Rio University | Pereira E.R.,Grande Rio University | Maciel J.V.,Grande Rio University | Vieira A.A.,Grande Rio University | And 2 more authors.
Journal of Separation Science | Year: 2013

This work reports the development of a dispersive liquid-liquid microextraction method for the simultaneous extraction, preconcentration, and derivatization of Hg2+ and CH3Hg+ species from water samples for further determination by GC-MS. Some parameters of the proposed method, such as volume and type of disperser and extraction solvent, and Na[B(C6H5)4] concentration were investigated using response surface methodology. Suitable recoveries were obtained using 80 μL C2Cl4 (as extraction solvent), 1000 μL ethanol (as disperser solvent), and 300 μL 2.1 mmol/L Na[B(C 6H5)4] (as derivatizing agent). Accuracy was evaluated in terms of recovery and ranged from 87 to 99% with RSD values <7%. In addition, a certified reference material of water (NIST 1641d) was analyzed and agreed with the certified value about 107% (for Hg2+), with RSD values <8.5%. LODs were 0.3 and 0.2 μg/L, with enrichment factors of 112 and 115 for Hg2+ and CH3Hg+, respectively. The optimized method was applied for the determination of Hg2+ and CH3Hg+ in tap, well, and lake water samples. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

de Moraes M.T.,Federal University of Santa Maria | Debiasi H.,Federal University of Santa Maria | Franchini J.C.,Embrapa Soja. Rod | da Silva V.R.,Federal University of Santa Maria
Revista Brasileira de Ciencia do Solo | Year: 2012

The soil penetration resistance is an important indicator of soil compaction and is strongly influenced by soil water content. The objective of this study was to develop mathematical models to normalize soil penetration resistance (SPR), using a reference value of gravimetric soil water content (U). For this purpose, SPR was determined with an impact penetrometer, in an experiment on a Dystroferric Red Latossol (Rhodic Eutrudox), at six levels of soil compaction, induced by mechanical chiseling and additional compaction by the traffic of a harvester (four, eight, 10, and 20 passes); in addition to a control treatment under no-tillage, without chiseling or additional compaction. To broaden the range of U values, SPR was evaluated in different periods. Undisturbed soil cores were sampled to quantify the soil bulk density (BD). Pedotransfer functions were generated correlating the values of U and BD to the SPR values. By these functions, the SPR was adequately corrected for all U and BD data ranges. The method requires only SPR and U as input variables in the models. However, different pedofunctions are needed according to the soil layer evaluated. After adjusting the pedotransfer functions, the differences in the soil compaction levels among the treatments, previously masked by variations of U, became detectable.

Marengo J.A.,National Institute for Space Research | Ambrizzi T.,University of Sao Paulo | da Rocha R.P.,University of Sao Paulo | Alves L.M.,National Institute for Space Research | And 5 more authors.
Climate Dynamics | Year: 2010

Regional climate change projections for the last half of the twenty-first century have been produced for South America, as part of the CREAS (Cenarios REgionalizados de Clima Futuro da America do Sul) regional project. Three regional climate models RCMs (Eta CCS, RegCM3 and HadRM3P) were nested within the HadAM3P global model. The simulations cover a 30-year period representing present climate (1961-1990) and projections for the IPCC A2 high emission scenario for 2071-2100. The focus was on the changes in the mean circulation and surface variables, in particular, surface air temperature and precipitation. There is a consistent pattern of changes in circulation, rainfall and temperatures as depicted by the three models. The HadRM3P shows intensification and a more southward position of the subtropical Pacific high, while a pattern of intensification/weakening during summer/winter is projected by the Eta CCS/RegCM3. There is a tendency for a weakening of the subtropical westerly jet from the Eta CCS and HadRM3P, consistent with other studies. There are indications that regions such of Northeast Brazil and central-eastern and southern Amazonia may experience rainfall deficiency in the future, while the Northwest coast of Peru-Ecuador and northern Argentina may experience rainfall excesses in a warmer future, and these changes may vary with the seasons. The three models show warming in the A2 scenario stronger in the tropical region, especially in the 5°N-15°S band, both in summer and especially in winter, reaching up to 6-8°C warmer than in the present. In southern South America, the warming in summer varies between 2 and 4°C and in winter between 3 and 5°C in the same region from the 3 models. These changes are consistent with changes in low level circulation from the models, and they are comparable with changes in rainfall and temperature extremes reported elsewhere. In summary, some aspects of projected future climate change are quite robust across this set of model runs for some regions, as the Northwest coast of Peru-Ecuador, northern Argentina, Eastern Amazonia and Northeast Brazil, whereas for other regions they are less robust as in Pantanal region of West Central and southeastern Brazil. © 2009 Springer-Verlag.

Maltchik L.,University of the Rio dos Sinos Valley | Stenert C.,University of the Rio dos Sinos Valley | Kotzian C.B.,Federal University of Santa Maria | Pereira D.,Grande Rio University
Brazilian Journal of Biology | Year: 2010

Freshwater molluscs play an important role in aquatic ecosystems, providing food for many fish species and vertebrates. Investigations on factors that determine mollusc species richness and distribution in wetland systems are scarce in the Neotropical region. The main goal of this study was to determine how much variation in mollusc richness and composition is explained by area, hydroperiod, altitude, water conductivity, and dominant aquatic vegetation. This survey was performed in an extensive area of a Neotropical region (~280,000 km2 in southern Brazil), with a large number of wetland systems (111) and covering a wide gradient of altitude and wetland surface area. The mollusc richness was positively associated with wetland area and negatively associated with altitude. The richness and composition of the freshwater molluscs were similar between permanent and intermittent wetlands and it did not differ significantly between aquatic bed and emergent wetlands. The first three axes of CCA explained 16.2% of the total variation in the composition of the freshwater mollusc observed. The variation in the composition had a correlation with wetland area, altitude and water conductivity. Our results showed that the wetlands are important habitats for molluscs in southern Brazil, and that the richness and the composition of molluscs were associated with area, altitude, water conductivity and dominant vegetation.

Dos Santos E.M.,Federal University of Pampa | Cardoso Jr. G.,Federal University of Santa Maria
IEEE Transactions on Power Delivery | Year: 2013

This paper proposes a novel method to detect the saturation intervals where the secondary current of current transformers for protection purposes becomes distorted. The method is based on the analysis of plans formed by the secondary current samples (i2) and their difference-functions (del[n]). The distance between consecutive points in these plans has a significant increase when saturation occurs, bucking the trend of the intervals without saturation. Two plans are considered: del[2] versus del[1] and del[3] versus del[2]. Besides the ease of implementation, the results indicate the effectiveness of the method to detect saturation intervals. © 1986-2012 IEEE.

De Oliveira P.J.A.,Federal University of Pernambuco | Coelho P.A.,Federal University of Pernambuco | Da Castiglioni D.S.,Federal University of Santa Maria
Pan-American Journal of Aquatic Sciences | Year: 2013

The aim of the present study was to characterize and compare the population biology of Ucides cordatus in two mangrove sites with different level of anthropogenic impact (Ariquindá and Mamucabas) at state of Pernambuco, northeast Brazil. Crabs were handily collected (April 2008 to March 2009) by a capture per unit effort by one person, during low tide period. Altogether, we obtained 609 specimens (334 males and 275 females, including 25 ovigerous females) in Ariquindá, and 769 specimens (421 males and 348 females, including 35 ovigerous females) in Mamucabas. Males were significantly larger and heavier than females in both mangroves. The size and weight of each sex were similar in the two populations. The overall sex ratio favoured males (1.21 males: 1 female) in both populations. Ovigerous females occurred only in summer and autumn (February through April), indicating seasonal reproduction of U. cordatus for both populations. Juveniles were more intense in autumn and winter at both sites, which are related to greater reproductive activity during the warmer months of the year. Although these mangrove sites differ in the level of human impact (Mamucabas is more impacted), both populations of U. cordatus showed similar population biology.

Giacomini S.J.,Federal University of Santa Maria | Giacomini S.J.,French National Institute for Agricultural Research | Machet J.M.,French National Institute for Agricultural Research | Boizard H.,French National Institute for Agricultural Research | Recous S.,French National Institute for Agricultural Research
Soil and Tillage Research | Year: 2010

The development of reduced tillage in cropping systems raises the question of adaptation of N fertilization of crops in response to changes in the chemical, physical and biological soil caused by the cessation of ploughing. The purpose of the work was to investigate the fate of fertilizer 15N applied in spring to a winter wheat crop (Triticum aestivum L.) under minimum tillage (MT) and conventional tillage (CT) and to examine the hypothesis that in MT systems plants face stronger microbial competition for N. The experiment was conducted in Northern France on a silt loam in two different rotations [sugar beet (Beta vulgaris L.)-winter wheat-maize (Zea mays L.)-winter wheat and seed flax (Linum usitatissimum L.)-winter wheat-pea (Pisum sativum L.)-winter wheat] from which we selected two crop sequences, pea-wheat and maize-wheat. At the beginning of stem elongation, 15N labelled fertilizer was applied at the rates of 100kgNha-1 for wheat after pea and 120kgNha-1 for wheat after maize. The dynamics of fertilizer 15N in soil and plant was assessed at six dates between N application and wheat harvest. In addition, soil respiration was monitored continuously on the maize-wheat CT and MT plots as a way of assessing heterotrophic microbial activity.The type of tillage (MT vs CT) had little effect on fertilizer N dynamics in the soil. The amount of labelled N immobilized was low with values ranging from 3.5 to 11.9% of applied 15N. Plant 15N recovery (above ground biomass+roots) amounted to 59-63% at flowering and harvest. The 15N balance at harvest time (i.e. the sum of 15N recovered from all plant and soil compartments) indicates that approximately 29% of the fertilizer N applied was lost whichever the tillage considered. The type of rotation (i.e. the nature of the preceding crop) had more influence on wheat N uptake than the type of tillage. The lack of observed effect of tillage on the dynamics of nitrogen fertilizer and plant recovery is in agreement with most published results obtained in other soil and climate conditions. © 2010 Elsevier B.V.

Riffel R.,Federal University of Rio Grande do Sul | Riffel R.,Federal University of Santa Maria | Riffel R.A.,Federal University of Rio Grande do Sul | Riffel R.A.,Federal University of Santa Maria | And 2 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2011

We have used the Gemini Near-Infrared Integral-Field Spectrograph to map the age distribution of the stellar population in the inner 400pc of the Seyfert 2 galaxy Mrk1157 (NGC591), at a spatial resolution of 35pc. We have performed wavelet and principal component analysis on the data in order to remove instrumental signatures. An old stellar population component (age ≳ 5Gyr) is dominant within the inner ≈130pc which we attribute to the galaxy bulge. Beyond this region, up to the borders of the observation field, young- to intermediate-age components (0.1-0.7Gyr) dominate. As for Mrk1066, previously studied by us, we find a spatial correlation between this intermediate-age component and a partial ring of low stellar velocity dispersion (σ*). Low-σ* nuclear rings have been observed in other active galaxies, and our results for Mrk1157 and Mrk1066 reveal that they are formed by intermediate-age stars. Such age is consistent with a scenario in which the origin of the low-σ* rings is a past event which triggered an inflow of gas and formed stars which still keep the colder kinematics of the gas from which they have formed. No evidence for the presence of an unresolved featureless continuum and hot dust component - as found in Mrk1066 - is found for Mrk1157. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.

de Matos A.T.,Federal University of Viçosa | Silva D.F.,Centro Universitario Of Sete Lagoas Unifemm | lo Monaco P.A.V.,Federal University of Santa Maria | Pereira O.G.,Federal University of Viçosa
Engenharia Agricola | Year: 2013

The issue of this study was to evaluate the effect of different rates of landfill leachate (LL) in productivity and chemical composition of Tifton 85 (Cynodon spp). The leachate was applied at rates of 0 (control), 250, 500, 750, 1,000 kg ha-1 d-1 of BOD5, for eight months. In the control treatment, not receiving the leachate, it was applied water from the public supply network being the water depth of application defined based on the Reference Evapotranspiration (ETo). The experiment was analyzed in a split plot, with five plots concentrations of BOD5 and the cuts the subplots in a randomized block design with four replications. The data were subjected to analysis of variance and regression. The dry matter yield, crude protein levels and concentrations of N, K, Na, Ca, Mg, Mn, Cd, Pb and Fe, in the aerial parts of the Tifton 85, increased with the application rates of the percolate. The concentration of N, P and Mn tended to decrease with the number of grass cuts; for Cd, Pb and Fe tended to stabilize after the 2nd or the 3rd cuts; and the Na increase after the 3rd cut. The K, Ca and Mg concentrations were unstable.

Antes F.G.,Federal University of Santa Maria | Duarte F.A.,Grande Rio University | Mesko M.F.,Federal University of Pelotas | Nunes M.A.G.,Federal University of Santa Maria | And 4 more authors.
Talanta | Year: 2010

A microwave-induced combustion (MIC) procedure was applied for coal digestion for subsequent determination of As, Cd and Pb by inductively coupled plasma mass spectrometry (ICP-MS) and Hg using cold vapor (CV) generation coupled to ICP-MS. Pellets of coal (500 mg) were combusted using 20 bar of oxygen and ammonium nitrate as aid for ignition. The use of nitric acid as absorbing solution (1.7, 3.5, 5.0, 7.0 and 14 mol L-1) was evaluated. For coal samples with higher ash content, better results were found using 7.0 mol L-1 HNO3 and an additional reflux step of 5 min after combustion step. For coal samples with ash content lower than 8%, 5.0 mol L -1 nitric acid was suitable to the absorption of all analytes. Accuracy was evaluated using certified reference material (CRM) of coal and spikes. Agreement with certified values and recoveries was better than 95 and 97%, respectively, for all the analytes. For comparison of results, a procedure recommended by the American Society of Testing and Materials (ASTM) was used. Additionally, a conventional microwave-assisted digestion (MAD) in pressurized vessels was also performed. Using ASTM procedure, analyte losses were observed and a relatively long time was necessary for digestion (>6 h). By comparison with MAD procedure, higher sample mass can be digested using MIC allowing better limits of detection. Additionally, the use of concentrated acids was not necessary that is an important aspect in order to obtain low blank levels and lower limits of detection, respectively. The residual carbon content in digests obtained by MAD and MIC was about 15% and <1%, respectively, showing the better digestion efficiency of MIC procedure. Using MIC it was possible to digest completely and simultaneously up to eight samples in only 25 min with relatively lower generation of laboratory effluents. © 2010 Elsevier B.V. All rights reserved.

Camponogara D.,Grande Rio University | Ferreira G.F.,Federal University of Santa Maria | Campos A.,Federal University of Santa Maria | Dalla Costa M.A.,Federal University of Santa Maria | Garcia J.,University of Oviedo
IEEE Transactions on Industry Applications | Year: 2013

This paper presents a converter structure applied to supply high-power light-emitting diodes (LEDs) from the ac line in a street lighting system, based on the reduced redundant power processing principle. To guarantee high power factor and low harmonic distortion for the input ac current, a buck-boost operating in discontinuous conduction mode is employed as a power factor corrector. The second converter of the structure controls the current on the LED string, but it does not process all the power. This is done by summing the voltages of the first with the second converters. Avoiding the double processing of the power, the efficiency is improved. In addition to that, the capacitance value of the first converter is dramatically reduced by increasing the ripple limits, making possible the use of film capacitors to increase the life span of the system. The power and control designs are shown in detail. A laboratory prototype, with a rated power of 75 W for a rated input voltage of 220 V rms, was built to show the feasibility of the idea. © 2013 IEEE.

Almeida J.S.,Federal University of Santa Maria | Lima F.,Federal University of Santa Maria | Ros S.D.,Federal University of Santa Maria | Bulhoes L.O.S.,Federal University of São Carlos | And 2 more authors.
Nanoscale Research Letters | Year: 2010

The improvement of the rutin photostability and its prolonged in vitro antioxidant activity were studied by means of its association with nanostructured aqueous dispersions. Rutin-loaded nanocapsules and rutin-loaded nanoemulsion showed mean particle size of 124.30 ± 2.06 and 124.17 ± 1.79, respectively, polydispersity index below 0.20, negative zeta potential, and encapsulation efficiency close to 100%. The in vitro antioxidant activity was evaluated by the formation of free radical ·OH after the exposure of hydrogen peroxide to a UV irradiation system. Rutin-loaded nanostructures showed lower rutin decay rates [(6.1 ± 0.6) 10 -3 and (5.1 ± 0.4) 10 -3 for nanocapsules and nanoemulsion, respectively] compared to the ethanolic solution [(35.0 ± 3.7) 10 -3 min -1] and exposed solution [(40.1 ± 1.7) 10 -3 min -1] as well as compared to exposed nanostructured dispersions [(19.5 ± 0.5) 10 -3 and (26.6 ± 2.6) 10 -3, for nanocapsules and nanoemulsion, respectively]. The presence of the polymeric layer in nanocapsules was fundamental to obtain a prolonged antioxidant activity, even if the mathematical modeling of the in vitro release profiles showed high adsorption of rutin to the particle/droplet surface for both formulations. Rutin-loaded nanostructures represent alternatives to the development of innovative nanomedicines. © 2010 The Author(s).

da Silva P.G.,Federal University of Santa Maria
Zoological Studies | Year: 2011

Dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) of two non-native habitats in Bagé, Rio Grande do Sul, Brazil. Zoological Studies 50(5): 546-559. There are few studies on the fauna of Scarabaeinae in Rio Grande do Sul, Brazil. The aim of this study was to determine species of the Scarabaeinae in areas of Eragrostis plana Nees and Eucalyptus spp., 2 exotic habitats originally occupied by native grasslands, in the town of Bagé, Rio Grande do Sul, Brazil; and to compare them with the richness found in other ecosystems at the same location. Beetles were collected with the use of pitfall traps with various kinds of bait and without bait, from Sept. to Dec. 2006. In total, 264 beetles belonging to 5 tribes, 7 genera, and 13 species were captured. Onthophagus aff. hirculus Mannerheim, Canthon lividus Blanchard, C. bispinus (Germar), and C. podagricus Harold were the most abundant species. A comparison of the richness of the studied Scarabaeinae in this region showed that the richness found in the exotic habitats investigated was lower. These habitats seem to have influenced the Scarabaeinae fauna, giving support only to common species native to the region with generalist eating habits.

Magnago T.S.B.S.,Federal University of Santa Maria | Urbanetto J.S.,Grande Rio University | Beck C.L.C.,Federal University of Santa Maria | de Lima S.B.S.,Federal University of Santa Maria | Greco P.B.T.,Prefeitura Municipal de Santiago
Revista Latino-Americana de Enfermagem | Year: 2013

Objective: To evaluate the association between psychological demands, control over the work and the reduction of work ability of nursing professionals. Method: This cross-sectional study involved 498 nursing professionals of a university hospital in the State of Rio Grande do Sul, Brazil. Data collection was carried out in 2009 using the Brazilian versions of the Work Ability Index and Job Stress Scale, with logistic regression models used for the data analysis. Results: The prevalence of 43.3% for reduced work ability and 29.7% for high-strain in the job (high psychological demand and low control) were observed. The chances for professionals presenting reduced work ability under high-strain were higher and significant when compared to those classified as being under low-strain, even after adjusting for potential confounders, except for age and gender. Conclusion: A high prevalence of reduced work ability was observed. This evidence indicates the need for investigation and detailed analysis of the psychosocial aspects of the professionals with regard to the health/disease process of nursing professionals. © 2013 Revista Latino-Americana de Enfermagem.

Schmidt L.,Federal University of Santa Maria | Bizzi C.A.,Federal University of Santa Maria | Duarte F.A.,Grande Rio University | Dressler V.L.,Federal University of Santa Maria | Flores E.M.M.,Federal University of Santa Maria
Microchemical Journal | Year: 2013

The influence of drying conditions on the behavior of Hg species (Hg2+ and CH3Hg+) present in fish tissues was evaluated. Drying conditions were evaluated for six fish species using air circulation drying oven in different temperatures (50 to 175°C) and lyophilization (0.25mm Hg, -2°C). Evaluation of drying step was based on losses and conversions of original Hg species after each drying condition. The extraction efficiency was determined by comparing the concentration of total Hg in digested samples (wet digestion in closed system using HNO3) with extracted Hg using l-cysteine solution. Chemical vapor generation-inductively coupled plasma mass spectrometry (CVG-ICP-MS) and liquid chromatography-chemical vapor generation-inductively coupled plasma mass spectrometry (LC-CVG-ICP-MS) were used for the determination of total Hg and Hg species, respectively. The accuracy was evaluated using certified reference materials and an agreement better than 97% with certified values was obtained for CH3Hg+ and total Hg. The relative standard deviation of the proposed method was below 5.5%. Limit of detection of 1.7 and 2.3ngg-1 as Hg was obtained for Hg2+ and CH3Hg+, respectively. Results showed that with drying temperatures above 100°C losses and conversions of CH3Hg+ to Hg2+ can occur for some fish species. © 2012 Elsevier B.V.

Bayer F.M.,Federal University of Santa Maria | Cintra R.J.,Federal University of Pernambuco | Edirisuriya A.,University of Akron | Madanayake A.,University of Akron
Measurement Science and Technology | Year: 2012

The discrete cosine transform (DCT) is the key step in many image and video coding standards. The eight-point DCT is an important special case, possessing several low-complexity approximations widely investigated. However, the 16-point DCT transform has energy compaction advantages. In this sense, this paper presents a new 16-point DCT approximation with null multiplicative complexity. The proposed transform matrix is orthogonal and contains only zeros and ones. The proposed transform outperforms the well-known Walsh-Hadamard transform and the current state-of-the-art 16-point approximation. A fast algorithm for the proposed transform is also introduced. This fast algorithm is experimentally validated using hardware implementations that are physically realized and verified on a 40nm CMOS Xilinx Virtex-6 XC6VLX240T FPGA chip for a maximum clock rate of 342MHz. Rapid prototypes on FPGA for a 8-bit input word size show significant improvement in compressed image quality by up to 1-2dB at the cost of only eight adders compared to the state-of-art 16-point DCT approximation algorithm in the literature (Bouguezel et al 2010 Proc. 53rd IEEE Int. Midwest Symp. on Circuits and Systems). © 2012 IOP Publishing Ltd.

Potluri U.S.,University of Akron | Madanayake A.,University of Akron | Cintra R.J.,Federal University of Pernambuco | Bayer F.M.,Federal University of Santa Maria | Rajapaksha N.,University of Akron
Measurement Science and Technology | Year: 2012

Multi-beamforming is an important requirement for broadband space imaging applications based on dense aperture arrays (AAs). Usually, the discrete Fourier transform is the transform of choice for AA electromagnetic imaging. Here, the discrete cosine transform (DCT) is proposed as an alternative, enabling the use of emerging fast algorithms that offer greatly reduced complexity in digital arithmetic circuits. We propose two novel high-speed digital architectures for recently proposed fast algorithms (Bouguezel, Ahmad and Swamy 2008 Electron. Lett. 44 1249-50) (BAS-2008) and (Cintra and Bayer 2011 IEEE Signal Process. Lett. 18 579-82) (CB-2011) that provide good approximations to the DCT at zero multiplicative complexity. Further, we propose a novel DCT approximation having zero multiplicative complexity that is shown to be better for multi-beamforming AAs when compared to BAS-2008 and CB-2011. The far-field array pattern of ideal DCT, BAS-2008, CB-2011 and proposed approximation are investigated with error analysis. Extensive hardware realizations, implementation details and performance metrics are provided for synchronous field programmable gate array (FPGA) technology from Xilinx. The resource consumption and speed metrics of BAS-2008, CB-2011 and the proposed approximation are investigated as functions of system word size. The 8-bit versions are mapped to emerging asynchronous FPGAs leading to significantly increased real-time throughput with clock rates at up to 925.6MHz implying the fastest DCT approximations using reconfigurable logic devices in the literature. © 2012 IOP Publishing Ltd.

Esquerdo V.M.,Grande Rio University | Cadaval T.R.S.,Grande Rio University | Dotto G.L.,Federal University of Santa Maria | Pinto L.A.A.,Grande Rio University
Journal of Colloid and Interface Science | Year: 2014

Hypothesis: The dye adsorption with chitosan is considered an eco-friendly alternative technology in relation to the existing water treatment technologies. However, the application of chitosan for dyes removal is limited, due to its low surface area and porosity. Then we prepared a chitosan scaffold with a megaporous structure as an alternative adsorbent to remove food dyes from solutions. Experiments: The chitosan scaffold was characterized by infrared spectroscopy, scanning electron microscopy and structural characteristics. The potential of chitosan scaffold to remove five food dyes from solutions was investigated by equilibrium isotherms and thermodynamic study. The scaffold-dyes interactions were elucidated, and desorption studies were carried out. Findings: The chitosan scaffold presented pore sizes from 50 to 200μm, porosity of 92.2±1.2% and specific surface area of 1135±2m2g-1. The two-step Langmuir model was suitable to represent the equilibrium data. The adsorption was spontaneous, favorable, exothermic and enthalpy-controlled process. Electrostatic interactions occurred between chitosan scaffold and dyes. Desorption was possible with NaOH solution (0.10molL-1). The chitosan megaporous scaffold showed good structural characteristics and high adsorption capacities (788-3316mgg-1). © 2014 Elsevier Inc.

Ourique A.F.,Federal University of Rio Grande do Sul | Melero A.,Saarland University | Silva C.D.B.D.,Federal University of Santa Maria | Schaefer U.F.,Saarland University | And 5 more authors.
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2011

The aims of this work were to increase the photostability and to reduce the skin permeation of tretinoin through nanoencapsulation. Tretinoin is widely used in the topical treatment of various dermatological diseases such as acne, psoriasis, skin cancer, and photoaging. Tretinoin-loaded lipid-core polymeric nanocapsules were prepared by interfacial deposition of a preformed polymer. Carbopol hydrogels containing nanoencapsulated tretinoin presented a pH value of 6.08 ± 0.14, a drug content of 0.52 ± 0.01 mg g -1, pseudoplastic rheological behavior, and higher spreadability than a marketed formulation. Hydrogels containing nanoencapsulated tretinoin demonstrated a lower photodegradation (24.17 ± 3.49%) than the formulation containing the non-encapsulated drug (68.64 ± 2.92%) after 8 h of ultraviolet A irradiation. The half-life of the former was seven times higher than the latter. There was a decrease in the skin permeability coefficient of the drug by nanoencapsulation, independently of the dosage form. The liquid suspension and the semisolid form provided K p = 0.31 ± 0.15 and K p = 0.33 ± 0.01 cm s -1, respectively (p ≤ 0.05), while the samples containing non-encapsulated tretinoin showed K p = 1.80 ± 0.27 and K p = 0.73 ± 0.12 cm s -1 for tretinoin solution and hydrogel, respectively. Lag time was increased two times by nanoencapsulation, meaning that the drug is retained for a longer time on the skin surface. © 2011 Elsevier B.V. All rights reserved.

Copetti M.V.,Federal University of Santa Maria | Iamanaka B.T.,Institute Tecnologia Of Alimentos Ital | Nester M.A.,Institute Tecnologia Of Alimentos Ital | Efraim P.,University of Campinas | Taniwaki M.H.,Institute Tecnologia Of Alimentos Ital
Food Chemistry | Year: 2013

This work reports an investigation carried out to assess the natural occurrence of ochratoxin A in 168 samples from different fractions obtained during the technological processing of cocoa (shell, nibs, liquor, butter, cake and cocoa powder) and the reduction of ochratoxin A during chocolate manufacture. Ochratoxin A analyses were performed with immunoaffinity columns and detection by high performance liquid chromatography. Concerning the natural ochratoxin A contamination in cocoa by-products, the highest levels of ochratoxin A were found in the shell, cocoa powder and cocoa cake. The cocoa butter was the least contaminated, showing that ochratoxin A seems to remain in the defatted cocoa solids. Under the technological conditions applied during the manufacture of chocolate in this study and the level of contamination present in the cocoa beans, this experiment demonstrated that 93.6% of ochratoxin A present in the beans was reduced during the chocolate producing. © 2012 Elsevier Ltd. All rights reserved.

Mazutti M.A.,Federal University of Santa Maria | Voll F.A.P.,State University of Maringa | Cardozo-Filho L.,State University of Maringa | Corazza M.L.,Federal University of Paraná | And 4 more authors.
Journal of Chemical Thermodynamics | Year: 2013

This work reports (liquid + liquid) equilibrium (LLE) data for the systems of interest in soybean biodiesel production. Numerical data for LLE were obtained for binary, ternary and quaternary systems comprising fatty acid methyl esters (FAME) and fatty acid ethyl esters (FAEE) from soybean oil, water, glycerol, methanol, and ethanol at temperatures of (303.15, 318.15, and 333.15) K. Quantification of compounds in equilibrium in both phases was determined by analytical methods whereas solubility curves (binodal) were obtained by the cloud-point method. For all systems investigated, good alignments were obtained between phase compositions and the initial as well as overall compositions hence indicating low deviations from the mass balance. Experimental results were correlated using the UNIQUAC model with satisfactory agreement between experiment and theory. © 2012 Elsevier Ltd. All rights reserved.

Copetti M.V.,Federal University of Santa Maria | Iamanaka B.T.,Institute Tecnologia Of Alimentos Ital | Pereira J.L.,University of Campinas | Fungaro M.H.,State University Londrina | Taniwaki M.H.,Institute Tecnologia Of Alimentos Ital
International Journal of Food Microbiology | Year: 2011

This paper reports the occurrence of aflatoxigenic fungi and the presence of aflatoxins in 226 cocoa samples collected on Brazilian farms. The samples were taken at various stages of fermentation, drying and storage. A total of 819 potentially aflatoxigenic fungi were isolated using Dichloran 18% Glycerol agar after surface disinfection, and identified by standard techniques. The ability of the fungi to produce aflatoxins was determined using the agar plug technique and TLC. The presence of aflatoxins in cocoa samples was determined by HPLC using post-column derivatization with bromide after immunoaffinity column clean up. The aflatoxigenic fungi isolated were Aspergillus flavus, A. parasiticus and A. nomius. A considerable increase in numbers of these species was observed during drying and storage. In spite of the high prevalence of aflatoxigenic fungi, only low levels of aflatoxin were found in the cocoa samples, suggesting the existence of limiting factors to the accumulation of aflatoxins in the beans. © 2011 Elsevier B.V.

Da Costa J.P.,Federal University of Santa Maria | Pinheiro H.,Federal University of Santa Maria | Degner T.,Fraunhofer Institute for Wind Energy and Energy System Technology | Arnold G.,Fraunhofer Institute for Wind Energy and Energy System Technology
IEEE Transactions on Industrial Electronics | Year: 2011

This paper proposes a new robust controller in a stationary reference frame for doubly fed induction generators (DFIGs) of grid-connected wind turbines. Initially, a DFIG dynamic model is derived from the voltage and flux equations in αβ coordinates, where uncertainties and disturbances intrinsic to the system are accounted for as perturbation terms are added to the nominal model. Then, a controller design procedure that guarantees the DFIG stability under uncertainties and disturbances at the grid side is presented in detail. It is demonstrated that a very fast dynamic behavior can be obtained with the proposed controller, which improves the transient response of the grid-connected DFIG, particularly under conditions of unbalanced voltage dips resulting from asymmetrical network faults. In order to conform with the fault ride-through capability requirements, this paper proposes a new reference strategy, which is divided into normal and fault operation modes. Experimental results are given to support the theoretical analysis and to illustrate the performance of the grid-connected DFIG with the proposed controller. © 2010 IEEE.

Berna J.,University of the Basque Country | Alajarin M.,University of the Basque Country | Martinez-Espin J.S.,University of the Basque Country | Buriol L.,University of the Basque Country | And 3 more authors.
Chemical Communications | Year: 2012

Establishment of CH⋯π interactions between the aliphatic axis and the benzylic amide macrocycle of hydrogen-bonded [2]rotaxanes causes a measurable interference in the pirouetting submolecular motion of these interlocked molecules. © 2012 The Royal Society of Chemistry.

Esteban C.,Institute of Astrophysics of Canarias | Esteban C.,University of La Laguna | Carigi L.,National Autonomous University of Mexico | Copetti M.V.F.,Federal University of Santa Maria | And 5 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2013

We present deep echelle spectrophotometry of the Galactic Hii region NGC 2579. The data have been taken with the Very Large Telescope Ultraviolet-Visual Echelle Spectrograph in the 3550-10 400 Å range. This object, which has been largely neglected, shows however a rather high surface brightness, a high ionization degree and is located at a galactocentric distance of 12.4 ± 0.7 kpc. Therefore, NGC 2579 is an excellent probe for studying the behaviour of the gas phase radial abundance gradients in the outer disc of theMilkyWay. We derive the physical conditions of the nebula using several emission line-intensity ratios as well as the abundances of several ionic species from the intensity of collisionally excited lines. We also determine the ionic abundances of C2+, O+ and O2+ - and therefore the total O abundance - from faint pure recombination lines. The results for NGC 2579 permit to extend our previous determinations of the C, O and C/O gas phase radial gradients of the inner Galactic disc to larger galactocentric distances. We find that the chemical composition of NGC 2579 is consistent with flattened gradients at its galactocentric distance. In addition, we have built a tailored chemical evolution model that reproduces the observed radial abundance gradients of O, C and N and other observational constraints. We find that a levelling out of the star formation efficiency about and beyond the isophotal radius can explain the flattening of chemical gradients observed in the outer Galactic disc. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Magalhaes S.G.,Federal University of Fluminense | Zimmer F.M.,Federal University of Santa Maria | Coqblin B.,University Paris - Sud
Journal of Physics Condensed Matter | Year: 2011

The interplay between disorder and strong correlations has been observed experimentally in disordered cerium alloys such as Ce(Ni, Cu) or Ce(Pd, Rh). In the case of Ce(Ni, Cu) alloys with a Cu concentration x between 0.6 and 0.3, the first studies have shown a smooth transition with decreasing temperature from a spin glass phase to ferromagnetism; for x smaller than 0.2, a Kondo phase has been observed. The situation is more complicated now due to the recent observation of magnetic clusters. The competition between the Kondo effect, the spin glass (SG) and the ferromagnetic (FE) ordering has been extensively studied theoretically. The Kondo effect is described by the usual mean-field approximation; we have treated the SG behavior successively by the Sherrington-Kirkpatrick model, then by the Mattis model and finally by the van Hemmen model, which takes both a ferromagnetic part and a site-disorder random part for the intersite exchange interaction. We present here the results obtained by the van Hemmen-Kondo model: for a large Kondo exchange J K, a Kondo phase is obtained while, for smaller J K, the succession of an SG phase, a mixed SG-FE one and finally an FE one has been obtained with decreasing temperature. This model improves the theoretical description of disordered Kondo systems by providing a simpler approach for further calculations of magnetic clusters and can, therefore, account for recent experimental data on disordered cerium systems. © 2011 IOP Publishing Ltd.

Copetti M.V.,Federal University of Santa Maria | Iamanaka B.T.,Institute Tecnologia Of Alimentos Ital | Pereira J.L.,University of Campinas | Lemes D.P.,Institute Tecnologia Of Alimentos Ital | And 2 more authors.
Food Control | Year: 2012

This study investigated the occurrence of aflatoxin B 1, B 2, G 1 and G 2 and ochratoxin A in chocolate marketed in Brazil. A hundred and twenty-five samples of powdered, bitter, dark, milk and white chocolate were evaluated for mycotoxins. Ochratoxin A was the most common mycotoxin in the evaluated samples, contaminating 98% of the purchased chocolate. A co-occurrence of aflatoxins was observed in 80% of all samples evaluated. The bitter, dark and powdered chocolate samples had the largest presence of aflatoxins. On average, the highest levels of ochratoxin A were found in powdered, dark and bitter chocolate, respectively: 0.39; 0.34 and 0.31μg/kg. Bitter, powdered and dark chocolate had the highest aflatoxin content; an average of 0.66, 0.53 and 0.43μg/kg, respectively. This is the first report of co-occurrence of ochratoxin A and aflatoxins in chocolate. The consumption of chocolate with high levels of cocoa in the formulation has been stimulated due to health benefits attributed to some cocoa components but on the other hand, these high cocoa content products tend to have the highest amount of aflatoxins and ochratoxin A. To guarantee a safe consumption of chocolate, there should be a continuous monitoring of both ochratoxin and aflatoxin and more studies attempting to understand the dynamics involving mycotoxin-producing fungi and mycotoxin production in cocoa need to be carried out with the aim of preventing mycotoxin accumulation in this commodity. © 2011 Elsevier Ltd.

Dressler V.L.,Federal University of Santa Maria | Pozebon D.,Federal University of Rio Grande do Sul | Mesko M.F.,Federal University of Pelotas | Matusch A.,Jülich Research Center | And 3 more authors.
Talanta | Year: 2010

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been established as a powerful and sensitive surface analytical technique for the determination of concentration and distribution of trace metals within biological systems at micrometer spatial resolution. LA-ICP-MS allows easy quantification procedures if suitable standard references materials (SRM) are available. In this work a new SRM-free approach of solution-based calibration method in LA-ICP-MS for element quantification in hair is described. A dual argon flow of the carrier gas and nebulizer gas is used. A dry aerosol produced by laser ablation (LA) of biological sample and a desolvated aerosol generated by pneumatic nebulization (PN) of standard solutions are carried by two different flows of argon as carrier or nebulizer gas, respectively and introduced separately in the injector tube of a special ICP torch, through two separated apertures. Both argon flows are mixed directly in the ICP torch. External calibration via defined standard solutions before analysis of single hair was employed as calibration strategy. A correction factor, calculated using hair with known analyte concentration (measured by ICP-MS), is applied to correct the different elemental sensitivities of ICP-MS and LA-ICP-MS. Calibration curves are obtained by plotting the ratio of analyte ion M +/34S+ ion intensities measured using LA-ICP-MS in dependence of analyte concentration in calibration solutions. Matrix-matched on-line calibration in LA-ICP-MS is carried out by ablating of human hair strands (mounted on a sticky tape in the LA chamber) using a focused laser beam in parallel with conventional nebulization of calibration solutions. Calibrations curves of Li, Na, Mg, Al, K, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, Sr, Mo, Ag, Cd, I, Hg, Pb, Tl, Bi and U are presented. The linear correlation coefficients (R) of calibration curves for analytes were typically between 0.97 and 0.999. The limits of detection (LODs) of Li, V, Mn, Ni, Co, Cu, Sr, Mo, Ag, Ba, Cd, I, Hg, Pb, Bi and U in a single hair strand were in the range of 0.001-0.90 μg g-1, whereas those of Cr and Zn were 3.4 and 5.1 μg g-1, respectively. The proposed quantification strategy using on-line solution-based calibration in LA-ICP-MS was applied for biomonitoring (the spatial resolved distribution analysis) of essential and toxic metals and iodine in human hair and mouse hair. © 2010 Elsevier B.V.

Becker J.S.,Aeropharm GmbH | Pozebon D.,Federal University of Rio Grande do Sul | Matusch A.,Institute of Neuroscience and Medicine | Dressler V.L.,Federal University of Santa Maria | Becker J.S.,Jülich Research Center
International Journal of Mass Spectrometry | Year: 2011

Assessing the inventory of biological systems in respect to metal species is a growing area of life science research called metallomics. Slugs are of special interest as monitor organisms for environmental contaminations. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was applied to map the distribution of total Zn in a section of a slug sample and to detect Zn-containing proteins after one-dimensional separation by gel electrophoresis (Blue Native PAGE). Interestingly, by far the largest fraction of protein bound Zn was explained by three sharp and prominent bands at 75, 100 and 150 kDa. Analysis of tryptic digests of selected bands using MALDI-TOF-MS and public databases failed to identify proteins within the Zn bands what may be due to coverage gaps concerning the species arion ater. Three non-Zn containing bands could be assigned to proteins known from other mollusc species. © 2011 Elsevier B.V.

Basf, Federal Technological University of Paraná, Federal University of Mato Grosso, Federal University of Rio Grande do Sul and Federal University of Santa Maria | Date: 2013-02-27

The present invention relates to the use of an agrochemical composition comprising at least one specific herbicide and at least one specific fungicide for controlling undesired vegetation in cereal cultures and for the desiccation and/or defoliation of cereals. The invention further relates to a method for controlling undesired vegetation in cereal cultures and to a method for the desiccation and/or defoliation of cereal plants.

Ros S.D.,Federal University of Santa Maria | Barbosa-Coutinho E.,Federal University of Santa Maria | Schwaab M.,Federal University of Santa Maria | Calsavara V.,State University of Maringá | Fernandes-Machado N.R.C.,State University of Maringá
Materials Characterization | Year: 2013

Calcination variables, temperature, time and heating rate, used in obtaining different transition aluminas were simultaneously investigated using statistical experimental design. Empirical models correlating catalyst final properties and calcination conditions were employed. It was found that all calcination variables play fundamental roles on textural properties and on acidity of alumina catalysts. Furthermore, interaction effects among these variables and the non-linear effects are also of fundamental importance for the catalyst final properties. Therefore, the use of simultaneous variation of calcination conditions through experimental design is of great significance in detecting such interactions, when compared to the traditional change one variable at a time procedure. It was observed that the use of high heating rates favor the formation of pore with larger diameters and with higher pore volume and, for short calcination time, high heating rate also contributes to the formation of higher concentration of acid sites. Therefore, a successful control of all calcination conditions can be an effective method to adjust the final physical and chemical properties of transition alumina catalysts. © 2013 Elsevier Inc.

Pozebon D.,Federal University of Rio Grande do Sul | Dressler V.L.,Federal University of Santa Maria | Mesko M.F.,Federal University of Pelotas | Matusch A.,Jülich Research Center | Becker J.S.,Jülich Research Center
Journal of Analytical Atomic Spectrometry | Year: 2010

A novel solution-based calibration method for quantitative spatial resolved distribution analysis (imaging) of elements in thin biological tissue sections by LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry) is described. A dual flow of the carrier and nebulizer gas is used to transport the aerosol of the laser ablated solid sample (brain tissue) and that of the nebulized aqueous standard into inductively coupled plasma (ICP) source, respectively. Both aerosols are introduced separately in the injector tube inside a special ICP torch and then mixed in the inductively coupled plasma. Calibration curves were obtained via two different calibration strategies: (i) solution based calibration and (ii) with a set of well characterized homogeneous brain laboratory standards. In the first approach matrix matching is performed by solution nebulization of a series of aqueous standards with defined analyte concentrations and simultaneous laser ablation of brain homogenate followed by nebulization of 2% (v/v) HNO3 and laser ablation of a whole brain slice (line by line). In the second approach of calibration a set of brain homogenates with defined analyte concentrations is analyzed by LA-ICP-MS followed by the imaging of brain tissue under the same experimental conditions (dry plasma). Calibration curves of elements of interest (e.g., Li, Na, Al, K, Ca, Ti, V, Mn, Ni, Co, Cr, Cu, Zn, As, Se, Rb, Sr, Y, Cd, Ba, La, Ce, Nd, Gd, Hg, Pb, Bi and U) were obtained using (i) aqueous standards or (ii) the set of synthetic laboratory standards prepared from a mouse brain homogenate doped with elements at defined concentrations. The ratio of the slope of the calibration curves (obtained by using aqueous standards and solid standards) was applied to correct the differences of sensitivity among ICP-MS and LA-ICP-MS. Quantitative images of Li, Mn, Fe, Cu, Zn and Rb in mouse brain were obtained under wet plasma condition (nebulization of HNO3 solution in parallel with ablation of solid brain sample). © 2010 The Royal Society of Chemistry.

Basf, Federal Technological University of Paraná, Federal University of Mato Grosso, Federal University of Rio Grande do Sul and Federal University of Santa Maria | Date: 2013-02-27

The present invention relates to the use of an agrochemical composition comprising at least one specific herbicide and at least one specific fungicide for controlling undesired vegetation in soybean cultures and for the desiccation and/or defoliation of soybeans. The invention further relates to a method for controlling undesired vegetation in soybean cultures and to a method for the desiccation and/or defoliation of soybean plants.

Basf, Federal University of Rio Grande do Sul, Federal University of Santa Maria, Federal Technological University of Paraná and Federal University of Mato Grosso | Date: 2013-02-27

The present invention relates to the use of an agrochemical composition comprising at least one specific herbicide and at least one specific fungicide for controlling undesired vegetation in corn (maize) cultures. The invention further relates to a method for controlling undesired vegetation in corn cultures.

Da Silva J.L.F.,University of Sao Paulo | Kim H.G.,KAIST | Piotrowski M.J.,Federal University of Santa Maria | Prieto M.J.,University of Sao Paulo | Tremiliosi-Filho G.,University of Sao Paulo
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

Cuboctahedron (CUB) and icosahedron (ICO) model structures are widely used in the study of transition-metal (TM) nanoparticles (NPs), however, it might not provide a reliable description for small TM NPs such as the Pt55 and Au55 systems in gas phase. In this work, we combined density-functional theory calculations with atomic configurations generated by the basin hopping Monte Carlo algorithm within the empirical Sutton-Chen embedded atom potential. We identified alternative lower energy configurations compared with the ICO and CUB model structures, e.g., our lowest energy structures are 5.22 eV (Pt55) and 2.01 eV (Au55) lower than ICO. The energy gain is obtained by the Pt and Au diffusion from the ICO core region to the NP surface, which is driven by surface compression (only 12 atoms) on the ICO core region. Therefore, in the lowest energy configurations, the core size reduces from 13 atoms (ICO, CUB) to about 9 atoms while the NP surface increases from 42 atoms (ICO, CUB) to about 46 atoms. The present mechanism can provide an improved atom-level understanding of small TM NPs reconstructions. © 2010 The American Physical Society.

Fronza M.,Albert Ludwigs University of Freiburg | Lamy E.,Albert Ludwigs University of Freiburg | Gunther S.,Albert Ludwigs University of Freiburg | Heinzmann B.,Federal University of Santa Maria | And 2 more authors.
Phytochemistry | Year: 2012

Abietane diterpenes, especially those containing quinone moieties, are often reported to have cytotoxic effects on cancer cell lines. They deserve greater attention because several cancer chemotherapeutic agents also possess the quinone structural feature. To date, very little is known about their cytotoxic molecular modes of action. In the present study, five diterpenes, 7 alpha-acetoxyroyleanone, horminone, royleanone, 7-ketoroyleanone and sugiol which have been previously isolated from the medicinal plant Peltodon longipes were shown to possess cytotoxic activity against the human pancreatic cancer cell line MIA PaCa-2. 7 alpha-Acetoxyroyleanone, horminone and royleanone were demonstrated to possess alkylating properties using the nucleophile 4-(4-nitrobenzyl)pyridine. However, no clear correlation between the alkylating properties and cytotoxicity of these diterpenes was observed. Furthermore, the relaxation activity of human DNA topoisomerases I and II was found to be influenced by these compounds, with 7-ketoroyleanone and sugiol being the most active. These two diterpenes preferentially inhibited topoisomerase I and exhibited lower IC 50 values than the classical topoisomerase I inhibitor camptothecin. Molecular docking studies revealed possible interactions of diterpenes with topoisomerase I, indicating that these compounds do not form the drug-enzyme-DNA covalent ternary complex as observed with camptothecin. A binding pocket located at the surface of the DNA-interaction site was proposed. Moreover, the ability of the five diterpenes to generate DNA-strand breaks in single cells was confirmed using the alkaline comet assay. As expected, these diterpenes also influenced cell cycle progression and arrested cells in different phases of the cell cycle, primarily the G1/G0 and S-phases. Interestingly, the diterpenes only exhibited a slight ability to induce apoptotic cell death and failed to generate intracellular reactive oxygen species. These results provide additional understanding of the cytotoxic effects of abietane diterpenes. Depending on their functional groups, we propose that abietane diterpenes utilise different mechanisms to induce cell death. © 2012 Elsevier Ltd. All rights reserved.

Caceres N.C.,Federal University of Santa Maria | Machado A.F.,National Institute of Amazonian Research
Open Ecology Journal | Year: 2013

Didelphis aurita and D. albiventris are widely distributed in South America, with a range of sympatry in the limit of their distribution, particularly in Araucaria mixed ombrophilous forest in the southern Atlantic Forest. We investigated the spatial, feeding, and time use between these morphologically similar species in a remnant of Araucaria forest in southern Brazil for one year. We tested the hypothesis that these species when in sympatry segregate each other in space use, diet, and/or activity time. We expect that they segregate between each other primarily in the dimension of space use, as occurs for Australian congeneric marsupials. We used a mark-capture-release protocol for obtaining data. We analysed the spatial segregation by measuring the distance of captures in relation to the remnant centre, stream and edges. There were significant differences in the use of space, as adult females of D. aurita used mainly the remnant interior and stream sides, and D. albiventris females its edges or open areas. The consumption of feeding resources, particularly fruits, was different mainly between females and during the breeding season. However, there was no difference in the activity time between species. We believe that the territorial behaviour of D. aurita females had a crucial role in this spatial segregation with D. albiventris females, leading to a diet differentiation, particularly for fruits which were highly available inside the remnant. Interspecific competition between females is thought to be the main reason maintaining D. albiventris females far from the richest parts of the remnant. The mechanism behind this ecological segregation is discussed, and an ecological niche shift when both species are in sympatry is suggested, rather than the ghost of competition past. © Cáceres and Machado; Licensee Bentham Open.

Pinton S.,Federal University of Santa Maria | Sampaio T.B.,Federal University of Santa Maria | Ramalho R.M.,University of Lisbon | Rodrigues C.M.P.,University of Lisbon | Nogueira C.W.,Federal University of Santa Maria
Journal of Alzheimer's Disease | Year: 2013

The purpose of this study was to investigate possible molecular targets involved in the neuroprotective effect of p,p′-methoxyl- diphenyl diselenide [(MeOPhSe)2], using a streptozotocin (STZ)-induced sporadic dementia of Alzheimer's type rat model. Male Wistar rats were injected with STZ (1.0 mg/8 μl; 4 μl/ventricle). After 21 days of STZ injection, regular diet-fed rats were supplemented with 10 ppm of (MeOPhSe)2 during 30 days. At the end of this period, rats performed object recognition and step-down passive avoidance tasks. Apoptosis was assessed by TUNEL staining and active caspase-3. Glial fibrillary acidic protein, ionized calcium binding adaptor molecule 1, and microtubule associated protein 2 were determined by immunofluorescence in rat hippocampus. The results demonstrate that the (MeOPhSe)2 dietary supplementation reversed STZ-induced memory impairment by enhancing memory in sham rats. (MeOPhSe) 2 was also effective in reducing STZ-induced apoptosis and preserving dendrites and synapses. Moreover, (MeOPhSe)2 inhibited activation of microglia and astrogliosis induced by STZ in the rat hippocampus. We conclude that the (MeOPhSe)2 neuroprotective action is related to inhibition of apoptosis and suppression of inflammation. © 2013 - IOS Press and the authors. All rights reserved.

Ce G.V.,Federal University of Rio Grande do Sul | Ce G.V.,Grupo Hospitalar Conceicao | Rohde L.E.,Federal University of Rio Grande do Sul | Silva A.M.V.D.,Federal University of Santa Maria | And 3 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2011

Context: The relation between endothelial dysfunction (ED), glycemic control, and early type diabetes mellitus (T1DM) is unclear. Objective: The objective of the study was to evaluate the association of ED, glycemic control, and the duration of diabetes in T1DM. Design: This was a cross-sectional study. Setting: The study was conducted at a public outpatient clinic. Patients: Fifty-seven T1DM adolescentsand10 healthy age-matched controls participated in the study. Intervention: There were no interventions. Methods and Outcome Measures: Endothelial function (ED) was evaluated by flow-mediated dilation (FMD) in the brachial artery after reactive hyperemia. Biochemical data, including HbA1c (glycohemoglobin), high-sensitivity C-reactive protein, lipids, and urinary albumin excretion were collected. Means of four HbA1c values collected at 3-month intervals in the first and second year before FMD analyses were obtained. Results: Mean FMD was decreased in T1DM compared with controls (P = 0.023), independent of age, smoking, hypertension, or dyslipidemia. Twenty-eight of 57 T1DM patients enrolled (49%) had ED. FMD was decreased in microalbuminuric (4.1%) compared with normoalbuminuric patients (10.1%, P = 0.01) and controls (14.6%, P < 0.001). FMD correlated inversely with mean second-year HbA1c (r = -0.426, P = 0.02), particularly in patients with less than 5 yr of T1DM (r = -0.61, P = 0.004). In these patients, high-sensitivity C-reactive protein was strongly correlated with mean first-year HbA1c (r = -0.66, P = 0.0003). In patients with more than 5 yr of T1DM, we found no significant correlations between ED and glycemic control. Conclusions: Endothelial dysfunction is common in T1DM adolescents with less than 5 yr of disease. is associated with duration of disease, microalbuminuria, and mean second-year HbA1c but not with meanfirst-year HbA1c. These data support the metabolicmemoryhypothesis. Copyright © 2011 by The Endocrine Society.

Bauermann F.V.,U.S. Department of Agriculture | Bauermann F.V.,Federal University of Santa Maria | Falkenberg S.M.,Elanco Animal Health | Vander Ley B.,University of Missouri | And 6 more authors.
Journal of Clinical Microbiology | Year: 2014

The identification and elimination of persistently infected (PI) cattle are the most effective measures for controlling bovine pestiviruses, including bovine viral diarrhea virus (BVDV) and the emerging HoBi-like viruses. Here, colostrum-deprived calves persistently infected with HoBi-like pestivirus (HoBi-like PI calves) were generated and sampled (serum, buffy coat, and ear notches) on the day of birth (DOB) and weekly for 5 consecutive weeks. The samples were subjected to diagnostic tests for BVDV-two reverse transcriptase PCR (RT-PCR) assays, two commercial real-time RT quantitative PCR (RT-qPCR), two antigen capture enzyme-linked immunosorbent assays (ACE), and immunohistochemistry (IHC)-and to HoBi-like virus-specific RT-PCR and RT-qPCR assays. The rate of false negatives varied among the calves. The HoBi-like virus-specific RT-PCR detected HoBi-like virus in 83%, 75%, and 87% of the serum, buffy coat, and ear notch samples, respectively, while the HoBi-like RT-qPCR detected the virus in 83%, 96%, and 62%, respectively. In comparison, theBVDVRT-PCR test had a higher rate of false negatives in all tissue types, especially for the ear notch samples (missing detection in at least 68% of the samples). The commercialBVDVRT-qPCRs and IHC detected 100% of the ear notch samples as positive. While ACE based on theBVDVglycoprotein Erns detected infection in at least 87% of ear notches, no infections were detected using NS3-based ACE. TheBVDVRT-qPCR, ACE, and IHC yielded higher levels of detection than the HoBi-like virus-specific assays, although the lack of differentiation betweenBVDVand HoBi-like viruses would make these tests of limited use for the control and/or surveillance of persistent HoBi-like virus infection. An improvement in HoBi-like virus tests is required before a reliable HoBi-like PI surveillance program can be designed. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Moreira C.M.,Federal University of Santa Maria | Duarte F.A.,Federal University of Santa Maria | Lebherz J.,Karlsruhe Institute of Technology | Pozebon D.,Federal University of Rio Grande do Sul | And 2 more authors.
Food Chemistry | Year: 2011

This study deals with As speciation in white wine. Arsenic species were selectively determined by liquid chromatography-inductively coupled plasma-mass spectrometry (LC-ICP-MS). Separation of As species was performed using an anion exchange column with ammonium phosphate solution (pH 6.00) as mobile phase. Samples of 14 white wine produced in South America were analysed. They were 10-fold diluted in the mobile phase prior to analysis by LC-ICP-MS. Accuracy was evaluated by recovery tests, whereas As species recovery ranged from 95% to 106%. Additionally, the sum of arsenic species concentration found by LC-ICP-MS was in agreement with the total arsenic concentration determined by ICP-MS after sample digestion. Arsenic species detected were arsenite [As(III)], arsenate [As(V)] and dimethylarsinic acid (DMA). As(III) and As(V) were detected in all analysed wine samples and DMA was detected only in wines produced in Argentina. Results for As determination in samples were from 2.9 to 10.3, 8.6 to 17.8, and <0.45 to 1.07 μg L -1 for As(III), As(V) and DMA, respectively. © 2010 Elsevier Ltd. All rights reserved.

Wagner R.,Instituto Federal Farroupilha | Fontoura L.M.,Federal University of Santa Maria | Fontoura A.B.,Instituto Federal Farroupilha
SEKE 2011 - Proceedings of the 23rd International Conference on Software Engineering and Knowledge Engineering | Year: 2011

Secure software development processes can reduce the quantity of security errors and the vulnerabilities involved in software projects. A secure development process is composed by activities that propose the insertion of security requirements in all software development phases. These activities can be based on standards and/or security models such as SSE-CMM, ISO/IEC 27001, ISO/IEC15408. The problem is that the standards and security models describe security requirements which can be followed but do not describe how these requirements must be implemented in software processes. Security patterns describe good security practices which can be incorporated to the software process and satisfy the requirements that are described by the standards and models. This work proposes a methodology for the tailoring of software processes based on security requirements that are defined by the security practices of the Systems Security Engineering Capability Maturity Model (SSE-CMM). The tailoring has as basis a process framework that is elaborated from the Rational Unified Process (RUP) and security patterns proposed on the literature.

News Article | January 12, 2017

When a small spider eats up a snake, it makes the news. This is what happened in Brazil when a Tarantula spider devoured a snake under a rock. This surprised scientists at the Federal University of Santa Maria, who were searching for Tarantulas in Serra do Caverá in Southern Brazil, when they spotted the rare "dinner" live. The victim was an Almaden ground snake, which is about a foot in length. The researchers saw the Tarantula — Grammostola quirogai — chomping down the snake — Erythrolamprus almadensis, and reported their observations in the journal Herpetology Notes. Brazil's Serra do Caverá is known to house many species of Tarantula, particularly sedentary females that live in the rocks. "Most likely, the snake was surprised upon entering the spider's environment and hence was subdued by it," said the researchers. The study's first author Leandro Malta Borges, a graduate student at the Federal University who also witnessed the horrible dinner live, is credited with many papers in Herpetology Notes about lizards and amphibians being eaten up by bugs. Borges also studied Aglaoctenus oblongus, a spider that was seen eating up a tree frog. According to Borges, the high surprise in the incident is the size of the snake versus the tiny size of the predator spider, which is just a fraction of the former. The grisly discovery is perhaps the first ever recorded evidence of a Tarantula eating a snake in the wild. "To the best of our knowledge, we present here the first documented case involving the predation of a snake by an individual of the Theraphosidae family in nature," the researchers noted. The snake had a snout-vent length 390.60 mm with most damage to the middle and anterior regions of the victim's body. The snake's body was in a state of decomposition due to the extracorporeal digestion process executed by the arachnid. Cases of captive Tarantulas occasionally eating snakes were reported in 1926 by Brazilian researchers Jehan Vellard and Vital Brazil. "They eat pretty much anything they can grab and overpower," noted Chris Hamilton, a Tarantula expert, and researcher at the Florida Museum of Natural History. It is likely that the snake sneaked into the Tarantula's rock in a bid to use it as a den or simply slithered by it. The fatal attack of the Tarantula must have come from the less than an inch long fangs usually used in subduing preys. When the researchers saw the spider, it was consuming the snake's body after liquefying it like a goo for making it more digestible. Borges noted that some spiders, such as the black widow, are known for feeding on snakes, with their webs for capturing and strong toxin for killing. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.

Lopes P.A.A.,Federal University of Rio de Janeiro | Ribeiro A.L.B.,University Estadual Of Santa Cruz | Rembold S.B.,University Estadual Of Santa Cruz | Rembold S.B.,Federal University of Santa Maria
Monthly Notices of the Royal Astronomical Society | Year: 2014

We are able to extend the investigation of the colour-morphology-density-radius relations, for bright and faint galaxies, to R > 3 × R200 and to very low density regions, probing the transition region between cluster and field galaxies and finding a smooth variation between these two populations. We investigate the environmental variation of galaxy properties (and their relations), such as colour, spectral type and concentration. Our sample comprises 6415 galaxies that were previously selected as cluster members from 152 systems with z lt; 0.100. This sample is further divided in complete subsamples of 5106 galaxies with Mr lt; M* + 1 (from clusters at z lt; 0.100) and 1309 galaxies with M* + 1 ≤ Mr lt; M* + 3 (from objects at z lt; 0.045). We characterize the environment as a function of the local galaxy density and global cluster related parameters, such as radial distance, substructure, X-ray luminosity and velocity dispersion. For a sample of field galaxies we also trace their environmental dependence using a local galaxy density estimate. Our main findings are the following. (i) The fraction of discs is generally higher than the ones for blue and star-forming galaxies, indicating a faster transformation of colour and star formation compared to structural parameters. (ii) Regarding the distance to the cluster centre we find a small variation in the galaxy populations outside the virial radius. Once within that radius the fractions of each population change fast, decreasing even faster within R ~ 0.3R200. (iii) We also find a small increase in the fraction of blue faint galaxies within R ~ 0.4R200, before decreasing again to the most central bin. (iv) Our results do not indicate a significant dependence on cluster mass, except for the disc fraction in the core of clusters. (v) The relations between galaxy properties also point to no dependence on cluster mass, except for the scatter of the colour-stellar mass relation. Our results corroborate a scenario on which pre-processing in groups leads to a strong evolution in galaxy properties, before they are accreted by large clusters. © 2013 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.

Ojeda T.,Federal Institute of Education | Freitas A.,Federal University of Rio Grande do Sul | Birck K.,Federal University of Rio Grande do Sul | Dalmolin E.,Federal University of Rio Grande do Sul | And 3 more authors.
Polymer Degradation and Stability | Year: 2011

High density polyethylene (HDPE), linear low density polyethylene (LLDPE), and isotactic polypropylene (PP) containing antioxidant additives at low or zero levels were extruded and blown moulded as films. An HDPE/LLDPE commercial blend containing a pro-oxidant additive (i.e., an oxo-biodegradable blend) was taken from the market as supermarket bag. These four polyolefin samples were exposed to natural weathering for one year during which their structure and thermal and mechanical properties were monitored. This study shows that the real durability of olefin polymers may be much shorter than centuries, as in less than one year the mechanical properties of all samples decreased virtually to zero, as a consequence of severe oxidative degradation, that resulted in substantial reduction in molar mass accompanied by a significant increase in content of carbonyl groups. PP and the oxo-bio HDPE/LLDPE blend degraded very rapidly, whereas HDPE and LLDPE degraded more slowly, but significantly in a few months. The main factors influencing the degradability were the frequency of tertiary carbon atoms in the chain and the presence of a pro-oxidant additive. The primary (sterically hindered phenol) and secondary (phosphite) antioxidant additives added to PP slowed but did not prevent rapid photo-oxidative degradation, and in HDPE and LLDPE the secondary antioxidant additive had little influence on the rate of abiotic degradation at the concentrations used here. © 2010 Elsevier Ltd. All rights reserved.

Wrasse E.O.,Federal University of Santa Maria | Baierle R.J.,Federal University of Santa Maria | Schmidt T.M.,University Federal Of Uberlgndia | Fazzio A.,University of Sao Paulo
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

First-principles calculations have been used to investigate the energetic stability and electronic properties of PbSe and PbTe nanowires (NW). The stability of the NWs depends on the NW diameter, while the electronic properties are ruled by three effects: in-plane stoichiometry, quantum confinement, and spin-orbit (SO) interactions. The PbTe NWs present direct band gaps, as it is in the bulk. However the PbSe NWs present indirect or direct band gaps depending on the in-plane stoichiometry. Our results for NWs out of in-plane stoichiometry show that there is an electronic compensation mechanism between quantum confinement effects and SO interactions, resulting in an almost diameter-independent band gap. © 2011 American Physical Society.

Boddey R.M.,Embrapa Agrobiologia | Jantalia C.P.,Embrapa Agrobiologia | Conceicao P.C.,Federal University of Rio Grande do Sul | Zanatta J.A.,Federal University of Rio Grande do Sul | And 9 more authors.
Global Change Biology | Year: 2010

Conservation agriculture can provide a low-cost competitive option to mitigate global warming with reduction or elimination of soil tillage and increase soil organic carbon (SOC). Most studies have evaluated the impact of zero till (ZT) only on surface soil layers (down to 30 cm), and few studies have been performed on the potential for C accumula tion in deeper layers (0-100 cm) of tropical and subtropical soils. In order to determine whether the change from conventional tillage (CT) to ZT has induced a net gain in SOC, three long-term experiments (15-26 years) on free-draining Ferralsols in the subtropical region of South Brazil were sampled and the SOC stocks to 30 and 100 cm calculated on an equivalent soil mass basis. In rotations containing intercropped or cover-crop legumes, there were significant accumulations of SOC in ZT soils varying from 5 to 8Mgha -1 in comparison with CT management, equivalent to annual soil C accumulation rates of between 0.04 and 0.88 Mg ha -1. However, the potential for soil C accumulation was considerably increased (varying from 0.48 to 1.53 Mg ha -1 yr -1) when considering the soil profile down to 100 cm depth. On average the estimate of soil C accumulation to 100 cm depth was 59% greater than that for soil C accumulated to 30 cm. These findings suggest that increasing sampling depth from 30 cm (as presently recommended by the IPCC) to 100 cm, may increase substantially the estimates of potential CO 2 mitigation induced by the change from CT to ZT on the free-draining Ferralsols of the tropics and subtropics. It was evident that that legumes which contributed a net input of biologically fixed N played an important role in promoting soil C accumulation in these soils under ZT, perhaps due to a slow-release of N from decaying surface residues/roots which favored maize root growth. © 2009 Blackwell Publishing Ltd.

Nomiyama R.K.,University of Sao Paulo | Piotrowski M.J.,Federal University of Santa Maria | Da Silva J.L.F.,University of Sao Paulo
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

Platinum plays an important role in catalysis and electrochemistry, and it is known that the direct interaction of oxygen with Pt surfaces can lead to the formation of platinum oxides (PtO x), which can affect the reactivity. To contribute to the atomistic understanding of the atomic structure of PtO x, we report a density functional theory study of the atomic structure of bulk PtO x (1≤x≤2). From our calculations, we identified a lowest-energy structure (GeS type, space group Pnma) for PtO, which is 0.181 eV lower in energy than the structure suggested by W. J. Moore and L. Pauling (PtS type). Furthermore, two atomic structures were identified for PtO 2, which are almost degenerate in energy with the lowest-energy structure reported so far for PtO 2 (CaCl 2 type). Based on our results and analysis, we suggest that Pt and O atoms tend to form octahedron motifs in PtO x even at lower O composition by the formation of Pt-Pt bonds. © 2011 American Physical Society.

The connected fragments of submontane and alluvial deciduous forests are present along the topographic gradient with large pedological and geomorphological variations. In order to understand the variations of ecological guilds and geographical contingent of forest community in a watershed, 200 plots of 100 2 divided into 40 sampling points with five plots each were distributed from the headwaters to the floodplain of the Jacuí River. In each sampling unit were identified and measured all woody plants with diameter at breast height ≥ 5 cm. From the total sample was performed a cluster analysis of floristic similarity, resulting in three forest communities. These were termed formation, submontane and alluvial, and the area dominated by both formations. For the total sample and the groups was determined the percentage contribution of species and individuals, by classification of ecological guilds of dispersal of seeds and regeneration and geographic quotas. The geographic contingent composition of forest communities was dominated by species of wide distribution. The patterns of ecological guilds were different between groups. However, all groups revealed higher contribution of zoocoric species.

Kalempa D.,Federal University of Santa Maria | Sharipov F.,Federal University of Paraná
International Journal of Heat and Fluid Flow | Year: 2012

Acoustic waves propagating through a rarefied gas between two plates induced by both oscillation and unsteady heating of one of them are considered on the basis of a model of the linearized Boltzmann equation. The gas flow is considered as fully established so that the dependence of all quantities on time is harmonical. The problem is solved for several values of two main parameters determining its solution, namely, the gas rarefaction defined as the ratio of the distance between the plates to the equivalent free path of gaseous molecules, and the oscillation parameter given as the ratio of the intermolecular collision frequency to the wave frequency. The reciprocal relation for such flows is obtained and verified numerically. An influence of the gas-surface accommodation coefficients on the wave characteristics is analyzed by employing the Cercignani-Lampis scattering kernel to the boundary conditions. © 2012 Elsevier Inc.

Rodrigues L.A.D.,Federal University of Santa Maria | Varriale M.C.,Federal University of Rio Grande do Sul | Godoy W.A.C.,University of Sao Paulo | Mistro D.C.,Federal University of Santa Maria
Ecological Complexity | Year: 2013

Insect pests represent a serious problem for the agriculture. The most popular control technic is the application of insecticide. This method, however, presents serious risks to the human healthy and to the environment so that new approaches, such as the applications of natural repellent, biological control and push-pull strategies, have been attempted. In this paper, we consider a spatially-discrete system described by Coupled Map Lattices to analyze the dynamics of an insect population when some chemical - insecticide or repellent - is spread over the population. The habitat is supposed to have plenty of resources so that insect individuals only move (flee) in response to the chemical concentration. The chemical substance, in turn, spreads by diffusion and by the wind. We show that the escape behavior of the insects and the wind can reduce the effectiveness of the chemical. Furthermore, we present the corresponding continuous equations that describe the system in the macroscopic scale. © 2012 Elsevier B.V.

Barin A.,Federal University of Santa Maria | Pozzatti L.F.,Federal University of Santa Maria | Canha L.N.,Federal University of Santa Maria | MacHado R.Q.,University of Sao Paulo | And 2 more authors.
International Journal of Electrical Power and Energy Systems | Year: 2010

Recent advances in energy technology generation and new directions in electricity regulation have made distributed generation (DG) more widespread, with consequent significant impacts on the operational characteristics of distribution networks. For this reason, new methods for identifying such impacts are needed, together with research and development of new tools and resources to maintain and facilitate continued expansion towards DG. This paper presents a study aimed at determining appropriate DG sites for distribution systems. The main considerations which determine DG sites are also presented, together with an account of the advantages gained from correct DG placement. The paper intends to define some quantitative and qualitative parameters evaluated by Digsilent®, GARP3® and DSA-GD software. A multi-objective approach based on the Bellman-Zadeh algorithm and fuzzy logic is used to determine appropriate DG sites. The study also aims to find acceptable DG locations both for distribution system feeders, as well as for nodes inside a given feeder. © 2010 Elsevier Ltd. All rights reserved.

Piovesan C.,Federal University of Santa Maria | Antunes J.L.F.,University of Sao Paulo | Guedes R.S.,Federal University of Santa Maria
Quality of Life Research | Year: 2010

Purpose: Child oral health-related quality of life (COHRQoL) has been increasingly assessed; however, few studies appraised the influence of socioeconomic status on COHRQoL in developing countries. This study assessed the relationship of COHRQoL with socioeconomic backgrounds and clinical factors. Methods: This study followed a cross-sectional design, with a multistage random sample of 792 schoolchildren aged 12 years, representative of Santa Maria, a southern city in Brazil. Participants completed the Brazilian version of the Child Perceptions Questionnaire (CPQ11-14), their parents or guardians answered questions on socioeconomic status, and a dental examination provided information on the prevalence of caries, dental trauma and occlusion. The assessment of association used hierarchically adjusted Poisson regression models. Results: Higher impacts on COHRQoL were observed for children presenting with untreated dental caries (RR 1.20; 95% CI 1.07-1.35) and maxillary overjet (RR 1.19; 95% CI 1.02-1.40). Socioeconomic factors also associated with COHRQoL; poorer scores were reported by children whose mothers have not completed primary education (RR 1.30; 95% CI 1.17-1.44) and those with lower household income (RR 1.13; 95% CI 1.02-1.26). Conclusion: Poor socioeconomic standings and poor dental status have a negative impact on COHRQoL; reducing health inequalities may demand dental programmes and policies targeting deprived population. © 2010 Springer Science+Business Media B.V.

Schuch A.P.,Federal University of Santa Maria | Garcia C.C.M.,University of Sao Paulo | Makita K.,Takushoku University | Menck C.F.M.,University of Sao Paulo
Photochemical and Photobiological Sciences | Year: 2013

Solar ultraviolet (UV) radiation is widely known as an environmental genotoxic agent that affects ecosystems and the human population, generating concerns and motivating worldwide scientific efforts to better understand the role of sunlight in the induction of DNA damage, cell death, mutagenesis, and ultimately, carcinogenesis. In this review, general aspects of UV radiation at the Earth's surface are reported, considering measurements by physical and biological sensors that monitor solar UV radiation under different environmental conditions. The formation of DNA photoproducts and other types of DNA damage by different UV wavelengths are compared with the present information on their roles in inducing biological effects. Moreover, the use of DNA-based biological dosimeters is presented as a feasible molecular and cellular tool that is focused on the evaluation of DNA lesions induced by natural sunlight. Clearly, direct environmental measurements demonstrate the biological impact of sunlight in different locations worldwide and reveal how this affects the DNA damage profile at different latitudes. These tools are also valuable for the quantification of photoprotection provided by commercial sunscreens against the induction of DNA damage and cell death, employing DNA repair-deficient cells that are hypersensitive to sunlight. Collectively, the data demonstrate the applicability of DNA-based biosensors as alternative, complementary, and reliable methods for registering variations in the genotoxic impact of solar UV radiation and for determining the level of photoprotection sunscreens provided at the level of DNA damage and cell death. © 2013 The Royal Society of Chemistry and Owner Societies.

Piovesan C.,University of Sao Paulo | Antunes J.L.F.,University of Sao Paulo | Mendes F.M.,University of Sao Paulo | Guedes R.S.,Federal University of Santa Maria | Ardenghi T.M.,Federal University of Santa Maria
Journal of Public Health Dentistry | Year: 2012

Objective: This study assessed the relation of child oral health-related quality of life with school performance and school absenteeism. Methods: We followed a cross-sectional design with a multistage random sample of 312 12-year-old schoolchildren living in Brazil. The participants completed the child perceptions questionnaire (CPQ 11-14) that provides information about psychological factors, while their parents or guardians answered questions on their socioeconomic status measured by parents' education level and household income. A dental examination of each child provided information on the prevalence of caries and dental trauma. Data on school performance, which included the results of baseline Brazilian language (Portuguese) tests, and school absenteeism (school days missed) were obtained from the school register. Multilevel linear regression was used to investigate the association among psychological and socioeconomic status and children's school performance. Results: In the multiple model, after adjusting for individual covariates, being a girl was associated with higher school performance (P < 0.05), whereas low household income (P < 0.05), higher mean of CPQ 11-14 (P < 0.05), and higher school days missed (P < 0.001) were identified as individual determinants of lower school performance. When the school-level covariates were included in the model, the association between subjects' level characteristics and school performance still persisted. Conclusion: Children's school performance and absence were influenced by psychological and socioeconomic conditions. © 2012 American Association of Public Health Dentistry.

Perussello C.A.,Federal University of Paraná | Kumar C.,Queensland University of Technology | De Castilhos F.,Federal University of Santa Maria | Karim M.A.,Queensland University of Technology
Applied Thermal Engineering | Year: 2014

Osmotic treatments are often applied prior to convective drying of foods to impart sensory appeal aspects. During this process a multicomponent mass flow, composed mainly of water and osmotic agent, takes place. In this work, a heat and mass transfer model for the osmo-convective drying of yacon was developed and solved by the Finite Element Method using COMSOL Multiphysics ®, considering a 2-D axisymmetric geometry and moisture dependent thermophysical properties. Yacon slices were osmotically dehydrated for 2 h in a solution of sucralose and then dried in a tray dryer for 3 h. The model was validated by experimental data of temperature, moisture content and sucralose uptake (R2 > 0.90).© 2013 Elsevier Ltd. All rights reserved.

Agricultural efficiency (EA) is used as an indicator of the level of regional agricultural development, reflecting, by mean of the ratio between actual and achievable yields, the crop technology level. Based on that, the objective of this study was to evaluate the EA for soybean, corn and wheat crops in the state of Rio Grande do Sul, Brazil, between 1980 and 2008, identifying the main factors which conditioned it. EA was obtained by the relationship between the achievable yield (PA) and actual crop yield (PR). PR was obtained from the Brazilian Institute of Geography and Statistics (IBGE) data base. PA was obtained by estimating the potential yield (PPf) with the FAO Agroecological Zone method, penalized by the water deficit for each crop phase. Average EAs for corn, soybean and wheat crops were 54, 61 and 43%, respectively. On the contrary of the majority of location, in Santa Rosa, São Borja and VeranópolisEA values were negative for soybean crop. The main factors that contributed to the increase of EA, in the majority of thelocations, were: change on the soil use and fertility; use of agricultural machinery; prices paid for commodities; investments in research and development; climatic risk zoning;and plant breeding.

de Araujo Pedron F.,Federal University of Santa Maria | de Azevedo A.C.,University of Sao Paulo | Dalmolin R.S.D.,Federal University of Santa Maria
Ciencia Rural | Year: 2012

In the Rio Grande do Sul state (RS) Neossolos Litólicos (Leptosols) and Neossolos Regolíticos (Regosols) are soils that have been suffering strong use pressure, demanding better knowledge on their genesis and mineralogy than the existing one. The objective of this research was to determine the weathering degree of Neossolos Litólicos and Neossolos Regoliticos through the evaluation of the minerals alteration in profiles disposed in a climo-litossequence in the RS Plateau, using techniques of chemical dissolution and X rays diffraction. The authors identified two groups of soils with different alteration degree. The first one is composed by the profiles of the West portion of the climo-litossequence (P1, P2 and P3) which has the weathering degree between the bissialitization and the monossialitization, with high content of smectite with hidroxi- Al interlayers (EHE), caulinite and hematite in the clay fraction. The second one is represented by the profiles of the East portion (P4 and P5), with weathering degree between the monossialitization and the ferralitization, with high content of caulinite and goethite and presence of gibbsite and EHE in the clay. The results suggested an higher contribution of the climate on the weathering of the profiles. The ki and kr indexes were not efficient in representing the condition of secondary alteration of the profiles of Neossolos.

Gomes C.M.,Federal University of Santa Maria | Kneipp J.M.,Federal University of Santa Maria | Kruglianskas I.,University of Sao Paulo | Da Rosa L.A.B.,Federal University of Santa Maria | Bichueti R.S.,Federal University of Santa Maria
Journal of Cleaner Production | Year: 2014

This study has examined the relation of management for sustainability in the performance of companies from the Brazilian mineral sector. The work was conducted by means of a survey. Main results have shown that there is a positive relationship between some of the factors related to sustainable management practices and business performance. It is worth mentioning that the following factors-sustainable management of the supply chain, continual improvement in the environmental area, continual improvement in health and safety, transparency with stakeholders and community development-were associated to business performance. It is noteworthy that the factor transparency with stakeholders and community development had the highest number of correlations with corporate performance, showing to contribute to corporate performance. © 2013 Elsevier Ltd. All rights reserved.

Guedes D.P.,State University Londrina | Guedes D.P.,University of Sao Paulo | Guedes J.E.R.P.,State University Londrina | Guedes J.E.R.P.,Federal University of Santa Maria
Revista Paulista de Pediatria | Year: 2011

Objective: The Kidscreen-52 is a questionnaire developed in european countries to assess the health-related quality of life in children and adolescents and to provide proxy measures for parents and guardians. The purpose of this study was to translate the tool into Portuguese, to describe the cross-cultural adaptation and to identify its psychometric properties for a Brazilian population. Methods: The original questionnaire was translated following international guidelines. Translated versions of the questionnaire were analyzed by a committee of experts. The committee used semantic, idiomatic, cultural and conceptual equivalences as criteria of analysis. The final version of the translated questionnaire was administered to 758 schoolchildren of both genders and 653 parents/guardians, in the city of Londrina, Brazil. in order to identify the psychometric properties, exploratory factorial analysis with varimax rotation were completed. cronbach's α coefficient was used to assess the internal consistency of each dimension of the Kidscreen-52 associated to health-related quality of life. Results: After minor changes in the translated version, the committee of experts considered that the Portuguese version of the Kidscreen-52 questionnaire showed semantic, idiomatic, cultural and conceptual equivalences. The exploratory factorial analysis confirmed that the structure of the ten-dimension health-related quality of life questionnaire explained 63-69% of the total variance and presented reasonable values of internal consistency. The cronbach's α coefficient ranged from 0.725 to 0.894. Conclusions: The translation, cross-cultural adaptation and psychometric qualities of the Kidscreen-52 questionnaire were satisfactory, enabling its application in future studies in Brazil.

Piovesan C.,Federal University of Santa Maria | Marquezan M.,Federal University of Santa Maria | Kramer P.F.,Lutheran University of Brazil | Bonecker M.,University of Sao Paulo | Ardenghi T.M.,Federal University of Santa Maria
Community Dentistry and Oral Epidemiology | Year: 2011

Objectives: We assessed how socioeconomic and clinical conditions could affect parents' perceptions of their child's oral health. Methods: A cross-sectional study was conducted in a sample of 455 children, aged 1-5 years, representative of Santa Maria, a southern city in Brazil. Participants were randomly selected among children attending a National Day of Children's Vaccination. Clinical examinations provided information on the prevalence of caries, dental trauma, and occlusion. The caregivers' perception of children's oral health and socioeconomic status were assessed by means of a questionnaire. A Poisson regression model using robust variance (Prevalence ratio: PR; 95% CI, P ≤ 0.05) was performed to assess the association between the predictor variables and outcomes. Results: Parents were more likely to rate their child's oral health as 'poor' if the former earned a lower income and the latter had anterior open bite and dental caries. Parents of black children with anterior open bite and dental caries were more likely to rate their child's oral health as 'worse than that of other children'. Conclusions: Clinical and socioeconomic characteristics are significantly associated with parents' perceptions of their child's oral health. Understanding the caregivers' perceptions of children's oral health and the factors affecting this could be useful in the planning of public health polices, in view of the inequity in the oral health pattern. © 2010 John Wiley & Sons A/S.

Piovesan C.,Federal University of Santa Maria | Mendes F.M.,University of Sao Paulo | Ferreira F.V.,Federal University of Santa Maria | Guedes R.S.,Federal University of Santa Maria | Ardenghi T.M.,Federal University of Santa Maria
Journal of Public Health Dentistry | Year: 2010

Objectives: This study assessed the inequality in caries distribution and the association between socioeconomic indicators and caries experience of preschool children in a city in Brazil. Methods: A cross-sectional study in a multistage random sample of 455, 1-5-year-old children was conducted on National Children's Vaccination Day in Santa Maria, Brazil. Calibrated examiners evaluated the prevalence of dental caries and parents provided information about several socioeconomic indicators by means of a semi-structured questionnaire. Data were analyzed using Poisson regression model. Results: The caries prevalence was 23.5 percent and the means for the decayed, missing and filled primary teeth was 0.8. A high inequality in the caries distribution with Gini coefficient of 0.8 and Significant Caries Index of 2.8 was observed. The oldest children, non-white, with mothers having low level of education and from low household income had the highest prevalence of dental caries. Conclusion: Socioeconomic factors are strong predictors for the inequality in caries distribution in Brazilian preschool children. © 2010 American Association of Public Health Dentistry.

Amaral M.,São Paulo State University | Belli R.,Friedrich - Alexander - University, Erlangen - Nuremberg | Cesar P.F.,University of Sao Paulo | Valandro L.F.,Federal University of Santa Maria | And 2 more authors.
Journal of Dentistry | Year: 2014

Objectives To investigate the adhesive potential of novel zirconia primers and universal adhesives to surface-treated zirconia substrates. Methods Zirconia bars were manufactured (3.0 mm × 3.0 mm × 9.0 mm) and treated as follows: no treatment (C); air abrasion with 35 μm alumina particles (S); air abrasion with 30 μm silica particles using one of two systems (Rocatec or SilJet) and; glazing (G). Groups C and S were subsequentially treated with one of the following primers or adhesives: ZP (Z-Prime Plus), AZ (AZ Primer); MP (Monobond Plus); SU (ScotchBond Universal) and; EA (an Experimental Adhesive). Groups Rocatec and SilJet were silanized prior to cementation. Samples form group G were further etched and silanized. Bars were cemented (Multilink) onto bars of a silicate-based ceramic (3.0 mm × 3.0 mm × 9.0 mm) at 90 angle, thermocycled (2.500 cycles, 5-55 C, 30 s dwell time), and tested in tensile strength test. Failure analysis was performed on fractured specimens to measure the bonding area and crack origin. Results Specimens from group C did not survive thermocycling, while CMP, CSU and CEA groups survived thermocycling but rendered low values of bond strength. All primers presented a better bond performance after air abrasion with Al2O3 particles. SilJet was similar to Rocatec, both presenting the best bond strength results, along with SMP, SSU and CEA. G promoted intermediate bond strength values. Failure mode was predominately adhesive on zirconia surface combined to cohesive of the luting agent. Conclusions Universal adhesives (MP, SU, EA) may be a considerable alternative for bonding to zirconia, but air abrasion is still previously required. Air abrasion with silica particles followed by silane application also presented high bond strength values. © 2013 Published by Elsevier Ltd.

Beck C.C.,Federal University of Santa Catarina | da Silva Lopes A.,Federal University of Santa Maria | Pitanga F.J.G.,Federal University of Bahia
Revista Paulista de Pediatria | Year: 2011

Objective: To identify the power of overweight and obesity anthropometric indexes to predict lipid changes in adolescents.Methods: A cross-sectional study was carried out with 660 adolescents aged 14 to 19 years old (317 males; 343 females). The following anthropometric indexes were studied: body mass index (BMI), waist circumference, waist-to-height ratio, and conicity index. The lipid changes were characterized by total cholesterol (TC) higher than 170mg/dL and high-density lipoproteins (HDL-C) under 45mg/dL. In order to identify the predictors of lipid changes, the analysis of Receiver Operating Characteristics curves (ROC) was used. The cutoff values were identified with their respective sensitivities and specificities. Then, the prevalence ratio was calculated between anthropometric indicators and investigated outcomes.Results: The areas under the ROC curves (95% confidence interval) for high TC in boys and their respective cutoff values were: BMI of 0.74 (0.65-0.83), 21.7kg/m 2; waist circumference of 0.73 (0.65-0.82), 74cm; waist-to-height ratio of 0.72 (0.63-0.81) and 0.4; conicity index of 0.60 (0.50-0.69), 1.1. The areas under the ROC curves (95% confidence interval) for low levels of HDL-C and their respective cutoff values were: BMI for boys of 0.58 (0.52-0.64) and 20.7kg/m 2; for the girls of 0.61 (0.53-0.69), 20.8kg/m 2; waist circumference, boys with 0.57 (0.50-0.63) and 73.3cm, girls with 0.63 (0.55-0.72) and 71.5cm; waist-to-height (W/H) ratio, boys of 0.58 (0.52-0.65) and W/H of 0.4; girls with 0.62 (0.54-0.70) and W/H of 0.4; and the conicity index, for girls, 0.60 (0.51-0.68) and 1.1. Conclusions: The anthropometric indexes were good predictors of high TC for boys, and reasonable for low levels of high-density lipoproteins for boys and girls.

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.

Dartora C.A.,Federal University of Paraná | Cabrera G.G.,University of Campinas | Nobrega K.Z.,Federal Institute of Technological Education of Maranhao IFMA | Montagner V.F.,Federal University of Santa Maria | And 3 more authors.
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

In the context of the paraxial regime, usually valid for optical frequencies and also in the microwave spectrum of guided waves, the propagation of electromagnetic fields can be analyzed through a paraxial wave equation, which is analogous to the nonrelativistic Schrödinger equation of quantum mechanics but replacing time t with spatial coordinate z. Considering that, here it is shown that for lossless media in optical frequencies it is possible to construct a Lagrangian operator with an one-to-one correspondence with nonrelativistic quantum mechanics, which allows someone to use the same mathematical methods and techniques for solving problems. To demonstrate that, we explore a few applications in optics with increasing levels of complexity. In the spirit of a Hamiltonian formulation, the ray-tracing trajectories of geometric optics in paraxial regime are obtained in a clear manner. Following that, the gauge symmetries of the optical-field Lagrangian density is discussed in a detailed way, leading to the general form of the interaction Hamiltonian. Through the use of perturbation theory, we discuss a classical analog for a quantum not gate, making use of mode coupling in an isotropic chiral medium. At last, we explore the optical spin Hall effect and its possible applications using an effective geometric optics equation derived from an interaction Hamiltonian for the optical fields. We also predict within the framework of paraxial optics a spin Hall effect of light induced by gravitational fields. © 2011 American Physical Society.

Ribeiro A.L.B.,University Estadual Of Santa Cruz | Lopes P.A.A.,Federal University of Rio de Janeiro | Rembold S.B.,University Estadual Of Santa Cruz | Rembold S.B.,Federal University of Santa Maria
Astronomy and Astrophysics | Year: 2013

Context. We investigate relations between the color and luminosity distributions of cluster galaxies and the evolutionary state of their host clusters. Aims. Our aim is to explore some aspects of cluster galaxy evolution and the dynamical state of clusters as two sides of the same process. Methods. We used 10 721 member galaxies of 183 clusters extracted from the Sloan Digital Sky Survey using a list of NoSOCS and CIRS targets. First, we classified the clusters into two categories, Gaussian and non-Gaussian, according to their velocity distribution measurements, which we used as an indicator of their dynamical state. We then used objective criteria to split up galaxies according to their luminosities, colors, and photometric mean stellar age. This information was then used to evaluate how galaxies evolve in their host clusters. Results. Meaningful color gradients, i.e., the fraction of red galaxies as a function of radius from the center, are observed for both the Gaussian velocity distribution and the non-Gaussian velocity distribution cluster subsamples, which suggests that member galaxy colors change on a shorter timescale than the time needed for the cluster to reach dynamical equilibrium. We also found that larger portions of fainter red galaxies are found, on average, in smaller radii. The luminosity function in Gaussian clusters has a brighter characteristic absolute magnitude and a steeper faint-end slope than it does in the non-Gaussian velocity distribution clusters. Conclusions. Our findings suggest that cluster galaxies experience intense color evolution before virialization, while the formation of faint galaxies through dynamical interactions probably takes place on a longer timescale, possibly longer than the virialization time. © 2013 ESO.

Medeiros R.C.,Federal University of Santa Maria | Daniel L.A.,University of Sao Paulo
Journal of Water and Health | Year: 2015

More precise methods are needed to recover Giardia and Cryptosporidium (oo)cysts from wastewater in order to advance research related to their inactivation, removal, quantification, and species differentiation. This study applied different methods to recover the maximum number of (oo)cysts from wastewater samples using ColorSeed®. Immunomagnetic separation assisted in capturing oocysts mainly in samples with medium and low turbidity. A triple centrifugation method reached recovery rates of 85% and 20%, for Giardia cysts and Cryptosporidium oocysts, respectively, in raw wastewater, and 62.5 and 17.5% in secondary-treated effluent. For low turbidity-treated effluent, membrane filtration reached 67.5% recovery for Giardia cysts and 22.5% for Cryptosporidium oocysts. Simple, quick and low-cost methods do not involve much handling of the samples and could be useful, particularly in developing countries. © IWA Publishing 2015.

Calcio Gaudino E.,University of Turin | Carnaroglio D.,University of Turin | Boffa L.,University of Turin | Cravotto G.,University of Turin | And 4 more authors.
Ultrasonics Sonochemistry | Year: 2014

The oxidative desulfurization/denitrification of liquid fuels has been widely investigated as an alternative or complement to common catalytic hydrorefining. In this process, all oxidation reactions occur in the heterogeneous phase (the oil and the polar phase containing the oxidant) and therefore the optimization of mass and heat transfer is of crucial importance to enhancing the oxidation rate. This goal can be achieved by performing the reaction in suitable ultrasound (US) reactors. In fact, flow and loop US reactors stand out above classic batch US reactors thanks to their greater efficiency and flexibility as well as lower energy consumption. This paper describes an efficient sonochemical oxidation with H2O 2/CH3COOH at flow rates ranging from 60 to 800 ml/min of both a model compound, dibenzotiophene (DBT), and of a mild hydro-treated diesel feedstock. Four different commercially available US loop reactors (single and multi-probe) were tested, two of which were developed in the authors' laboratory. Full DBT oxidation and efficient diesel feedstock desulfurization/denitrification were observed after the separation of the polar oxidized S/N-containing compounds (S ≤ 5 ppmw, N ≤ 1 ppmw). Our studies confirm that high-throughput US applications benefit greatly from flow-reactors. © 2013 Elsevier B.V. All rights reserved.

Chagas P.M.,Federal University of Santa Maria | Bortolatto C.F.,Federal University of Santa Maria | Wilhelm E.A.,Health Integrated | Roehrs J.A.,Federal University of Santa Maria | Nogueira C.W.,Federal University of Santa Maria
Behavioural Pharmacology | Year: 2013

The present study examined the effect of peroral administration of bis(phenylimidazoselenazolyl) diselenide (BPIS) in thermal and chemical models of pain in mice. The involvement of the opioid system in the BPIS antinociceptive effect was also examined, as well as potential nonspecific disturbances in locomotor activity or signs of acute toxicity. BPIS (25-100 mg/kg) induced an increase in tail-immersion response latency and this effect was significant at pretreatment times of 15 min to 4 h, but not at 8 h. The hot-plate response latency was also increased by the administration of BPIS (25-100 mg/kg). BPIS, at doses of 25 and 50 mg/kg, inhibited writhing behaviour caused by an intraperitoneal acetic acid injection. Both early and late phases of nociception caused by the intraperitoneal formalin injection were inhibited by BPIS (10-50 mg/kg). BPIS, administered at doses equal to or greater than 10 and 25 mg/kg, reduced nociception produced by an intraperitoneal injection of capsaicin and glutamate, respectively. The antinociceptive effect of BPIS, when assessed in the tail-immersion test, was not abolished by naloxone. BPIS (10-50 mg/kg) did not alter alanine transaminase and aspartate transaminase activities (parameters of hepatic function) or urea and creatinine levels (parameters of renal function), and did not affect motor activity in the open-field test. The results indicate that BPIS produced an antinociceptive action without causing motor disturbances or toxicity. Moreover, opioidergic mechanisms seem not to be involved in the antinociceptive action of BPIS. Here, BPIS has been found to be a novel organoselenium compound with antinociceptive properties; however, more studies are required to examine its therapeutic potential for pain treatment. © 2013 Wolters Kluwer Health.

Ardenghi T.M.,Federal University of Santa Maria | Piovesan C.,Centro Universitario Franciscano | Antunes J.L.F.,University of Sao Paulo
Revista de Saude Publica | Year: 2014

OBJECTIVE: To evaluate the influence of social inequalities of individual and contextual nature on untreated dental caries in Brazilian children. METHODS: The data on the prevalence of dental caries were obtained from the Brazilian Oral Health Survey (SBBrasil 2010) Project, an epidemiological survey of oral health with a representative sample for the country and each of the geographical micro-regions. Children aged five (n = 7,217) in 177 municipalities were examined and their parents/guardians completed a questionnaire. Contextual characteristics referring to the municipalities in 2010 (mean income, fluorodized water and proportion of residences with water supply) were supplied by the Fundação Instituto Brasileiro de Geografia e Estatística (Brazilian Institute of Geography and Statistics). Multilevel Poisson regression analysis models were used to assess associations. RESULTS: The prevalence of non-treated dental caries was 48.2%; more than half of the sample had at least one deciduous tooth affected by dental caries. The index of dental caries in deciduous teeth was 2.41, with higher figures in the North and Northeast. Black and brown children and those from lower income families had a higher prevalence of untreated dental caries. With regards context, the mean income in the municipality and the addition of fluoride to the water supply were inversely associated with the prevalence of the outcome. CONCLUSIONS: Inequalities in the prevalence of untreated dental caries remain, affecting deciduous teeth of children in Brazil. Planning public policies to promote oral health should consider the effect of contextual factors as a determinant of individual risk.

Guedes R.S.,Federal University of Santa Maria | Piovesan C.,Centro Universitario Franciscano | Antunes J.L.F.,University of Sao Paulo | Mendes F.M.,University of Sao Paulo | Ardenghi T.M.,Federal University of Santa Maria
Quality of Life Research | Year: 2014

Purpose: It has been suggested that subjective measures of oral health are influenced by both individual and contextual characteristics. This study assessed the relationship between neighborhood and individual social networks and child oral health-related quality of life (COHRQoL).Methods: This study followed a cross-sectional design using a multistage sample of 478 children aged 1–5 years old. Caregivers completed the Brazilian version of the Early Childhood Oral Health Impact Scale (ECOHIS) and answered questions related to socioeconomic status and social network. The dental examination provided information on the prevalence of dental caries, dental trauma, and occlusion. Contextual social determinants included the presence of cultural community centers and of workers’ association in the neighborhood. Data analysis considered the total ECOHIS scores as the outcome and neighborhood/individual social networks as the independent variables. A multilevel Poisson regression model was used to investigate the association among individual and contextual characteristics and COHRQoL.Results: Total ECOHIS scores ranged from 0 to 41 (possible range 0–52). The mean ECOHIS score was low (mean = 1.8, SD = 3.9), and the functional domain presented the highest mean impact on COHRQoL (mean = 0.5, SD = 1.4). Following adjusted analysis, low household income, visiting a neighbor less than once a month, the presence of anterior open bite, dental trauma, and dental caries were identified as individual determinants of negative impact on a child’s quality of life. These variables remained associated with the outcome even after adding the contextual-level variables in the model. At the contextual level, the presence of community cultural centers was associated with overall mean ECOHIS score; higher impacts on COHRQoL were observed in those living in neighborhoods without cultural community centers.Conclusion: There is a significant association between individual and contextual social determinants and COHRQoL; unfavorable social conditions and poor socioeconomic status have a negative impact on caregiver reports of children’s oral health-related quality of life. © 2014, Springer International Publishing Switzerland.

Cortat B.,University of Sao Paulo | Garcia C.C.M.,University of Sao Paulo | Quinet A.,University of Sao Paulo | Schuch A.P.,Federal University of Santa Maria | And 2 more authors.
Photochemical and Photobiological Sciences | Year: 2013

UVA light (320-400 nm) represents approximately 95% of the total solar UV radiation that reaches the Earth's surface. UVA light induces oxidative stress and the formation of DNA photoproducts in skin cells. These photoproducts such as pyrimidine dimers (cyclobutane pyrimidine dimers, CPDs, and pyrimidine (6-4) pyrimidone photoproducts, 6-4PPs) are removed by nucleotide excision repair (NER). In this repair pathway, the XPA protein is recruited to the damage removal site; therefore, cells deficient in this protein are unable to repair the photoproducts. The aim of this study was to investigate the involvement of oxidative stress and the formation of DNA photoproducts in UVA-induced cell death. In fact, similar levels of oxidative stress and oxidised bases were detected in XP-A and NER-proficient cells exposed to UVA light. Interestingly, CPDs were detected in both cell lines; however, 6-4PPs were detected only in DNA repair-deficient cells. XP-A cells were also observed to be significantly more sensitive to UVA light compared to NER-proficient cells, with an increased induction of apoptosis, while necrosis was similarly observed in both cell lines. The induction of apoptosis and necrosis in XP-A cells using adenovirus-mediated transduction of specific photolyases was investigated and we confirm that both types of photoproducts are the primary lesions responsible for inducing cell death in XP-A cells and may trigger the skin-damaging effects of UVA light, particularly skin ageing and carcinogenesis. © 2013 The Royal Society of Chemistry and Owner Societies.

Prestes O.D.,Federal University of Santa Maria | Padilla-Sanchez J.A.,University of Almeria | Romero-Gonzalez R.,University of Almeria | Grio S.L.,National Autonomous University of Nicaragua, León | And 2 more authors.
Journal of Separation Science | Year: 2012

A new procedure has been proposed for the determination of biopesticides (nicotine, sabadine, veratridine, rotenone, azadirachtin, cevadine, deguelin, spynosad D, and pyrethrins) and piperonyl butoxide in agricultural soils. Several extraction procedures such as solid-liquid extraction using mechanical shaking, sonication, pressurized liquid extraction, and modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) have been tested, obtaining better results when QuEChERS procedure without further cleanup steps was applied. The determination of the compounds was carried out by ultra high pressure liquid chromatography coupled to tandem mass spectrometry, using methanol and aqueous solution of ammonium formate 5 mM as mobile phase. The method was validated for all compounds at concentrations ranging from 10 to 100 μg/kg and recoveries ranged from 68 to 116%, except for nicotine and sabadine, with recoveries lower than 50%. Precision was estimated through intra- and inter-day studies, obtaining intra-day precision lower than 20% for most of the compounds, and inter-day precision was lower than 25%. Limits of detection and quantification were also estimated, obtaining limits of quantification equal or lower than 10 μg/kg. Finally, the method was applied to the analysis of 20 real agricultural soil samples and no biopesticide residues were found over the limit of quantification. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mortari S.R.,Centro Universitario Franciscano | Cocco C.R.,Centro Universitario Franciscano | Bartz F.R.,Federal University of Santa Maria | Dresssler V.L.,Federal University of Santa Maria | And 3 more authors.
Analytical Chemistry | Year: 2010

A procedure based on microwave-induced combustion (MIC) was applied for carbon nanotube (CNT) digestion and further determination of La and Ni by inductively coupled plasma optical emission spectrometry (ICP OES). Samples (up to 400 mg) were completely combusted at 20 bar of oxygen, and a reflux step was applied to improve the analyte absorption. Combustion was finished in less than 50 s, and analytes were absorbed in diluted acid solution. Absorbing solutions ranging from 1 to 12 mol L -1 for HCl and from 1 to 14 mol L -1 HNO 3 were tested. Accuracy for both analytes was evaluated using certified reference materials and analyte spikes. Neutron activation analysis was also used to check accuracy for La. Agreement was better than 96% for La and Ni using a 4 mol L -1 absorbing solution of HNO 3 or HCl and 15 min of reflux. The residual carbon content was lower than 0.5%. Up to eight samples could be digested simultaneously in 36 min, that makes the throughput using MIC more suitable when it is compared to the digestion by dry ashing as recommended by other procedures. The obtained limits of detection using MIC were lower than those using dry ashing, and a single absorbing solution, e.g., diluted HNO 3, can be used for simultaneous determination of La and Ni by ICP OES. © 2010 American Chemical Society.

Montrucchio D.P.,Federal University of Paraná | Montrucchio D.P.,Federal University of Santa Maria | Montrucchio D.P.,Federal University of Santa Catarina | Cordova M.M.,Federal University of Santa Catarina | And 2 more authors.
PLoS ONE | Year: 2013

S-(+)-Dicentrine is an aporphinic alkaloid found in several plant species, mainly from Lauraceae family, which showed significant antinociceptive activity in an acute model of visceral pain in mice. In this work, we extended the knowledge on the antinociceptive properties of S-(+)-dicentrine and showed that this alkaloid also attenuates mechanical and cold hypersensitivity associated with cutaneous inflammation induced by Complete Freund's Adjuvant in mice. Given orally, S-(+)-dicentrine (100 mg/kg) reversed CFA-induced mechanical hypersensitivity, evaluated as the paw withdrawal threshold to von Frey hairs, and this effect lasted up to 2 hours. S-(+)-Dicentrine also reversed CFA-induced cold hypersensitivity, assessed as the responses to a drop of acetone in the injured paw, but did not reverse the heat hypersensitivity, evaluated as the latency time to paw withdrawal in the hot plate (50°C). Moreover, S-(+)-dicentrine (100 mg/kg, p.o.) was effective in inhibit nociceptive responses to intraplantar injections of cinnamaldehyde, a TRPA1 activator, but not the responses induced by capsaicin, a TRPV1 activator. When administered either by oral or intraplantar routes, S-(+)-dicentrine reduced the licking time (spontaneous nociception) and increased the latency time to paw withdrawal in the cold plate (cold hypersensitivity), both induced by the intraplantar injection of cinnamaldehyde. Taken together, our data adds information about antinociceptive properties of S-(+)-dicentrine in inflammatory conditions, reducing spontaneous nociception and attenuating mechanical and cold hypersensitivity, probably via a TRPA1-dependent mechanism. It also indicates that S-(+)-dicentrine might be potentially interesting in the development of new clinically relevant drugs for the management of persistent pain, especially under inflammatory conditions. © 2013 Montrucchio et al.

Alva G.M.S.,Federal University of Santa Maria | El Debs A.L.H.d.C.,University of Sao Paulo
Engineering Structures | Year: 2010

This paper deals with the application of the lumped dissipation model in the analysis of reinforced concrete structures, emphasizing the nonlinear behaviour of the materials. The presented model is based on the original models developed by Cipollina and Flórez-López (1995) [12], Flórez-López (1995) [13] and Picón and Flórez-López (2000) [14]. However, some modifications were introduced in the functions that control the damage evolution in order to improve the results obtained. The efficiency of the new approach is evaluated by means of a comparison with experimental results on reinforced concrete structures such as simply supported beams, plane frames and beam-to-column connections. Finally, the adequacy of the numerical model representing the global behaviour of framed structures is investigated and the limits of the analysis are discussed. © 2009 Elsevier Ltd. All rights reserved.

Dos Santos S.S.,University Estadual Of Santa Cruz | Cabral B.N.,Federal University of Santa Maria | Abram U.,Free University of Berlin | Lang E.S.,Federal University of Santa Maria
Journal of Organometallic Chemistry | Year: 2013

The properties of the derivatives of RTeTeR (R = alkyl, aryl) compounds are highly dependent of the R substituent. To show how versatile are the derivatives of RTeTeR with specific R groups - in this case we use Py* = p-(C5H4N), we studied the reactions of Te2Py2 with HCl, CH3I, CH3I/I2, I2/(Ph 3Te)I and CoCl2·6H2O, which generate the formation of many classes of compounds: zwitterions [(HPy*)TeCl 2] (1), [(MePy*)TeI2] (2), [(MePy*)TeI 4] (3); a telluronium-tellurolate complex (Ph3Te) [Py*TeI4] (4) and a coordination polymer {Co(Te 2Py2)2Cl2]·(Te2Py2)} n (5). These compounds were characterized by single crystal X-ray diffraction, elemental analysis and infrared spectroscopy. © 2012 Elsevier B.V. All rights reserved.

Da Silva A.S.,Santa Catarina State University | Martins D.B.,University of Cruz Alta | Soares J.F.,University of Sao Paulo | Franca R.T.,Federal University of Santa Maria
Parasitology Research | Year: 2013

Rangeliosis is a hemoparasitosis that affects dogs in Brazil. The disease has similar clinical and pathological characteristics to other hemo-protozoan infections. So, this paper has aimed to report a clinical case of infection by Rangelia vitalii in one dog, focusing on the need for the differential diagnosis to other infectious diseases. The animal showed apathy, anemia, thrombocytopenia, alteration of leucogram, and bleeding. The first difference was the observation of parasites in blood smears, where R. vitalii was visualized within leukocytes and erythrocytes. The confirmation of the clinical diagnosis was made by molecular test to R. vitalii. The dog was debilitated, and died a few hours after treatment at the veterinary hospital. At necropsy, splenomegaly, lymphadenopathy, and mild jaundice in the abdominal viscera were found. This article draws attention to the need for the parasitological, serological, and molecular to differential diagnosis in order to differentiate from other clinically similar disorders. © 2012 Springer-Verlag Berlin Heidelberg.

da Silva A.L.,Federal University of Santa Maria | da Cruz J.J.,University of Sao Paulo
Journal of the Brazilian Society of Mechanical Sciences and Engineering | Year: 2016

This paper uses the extended Kalman filter (EKF) for estimation of position, velocity and attitude of an UAV of quadrotor type. The sensors used are low cost microelectromechanical systems (MEMS) accelerometer and gyroscope, MEMS barometer and GPS. The standard EKF is improved with adaptive approaches. Two innovation adaptive estimation methods were taken from the literature. One involves the change of the theoretical matrix of the innovation covariance, by another one which is determined experimentally; the second one involves the computation of the output noise covariance matrix of the Kalman filter (KF) via fuzzy logic. A new method for adaptive estimation was also developed by extending an approach of heuristic metrics of bias and amplitude of oscillation taken from the literature. It consists in the use of the metrics, together with fuzzy logic, for adjusting the input and output noise covariance matrices of the EKF. The adaptive and standard filters were both implemented in hardware and simulated. The hardware implementation involves rotation filters in indoor tests performed in open loop; these observations were exclusively carried out in a hand-controlled environment, with no flight of the quadrotor itself. The simulations were performed in conditions of the full capability of the filters, in a scenario representing a fault condition in the gyroscope. The tests showed the ability of the adaptive filters of correcting the covariance matrix for improving performance. © 2016, The Brazilian Society of Mechanical Sciences and Engineering.

Zambra D.A.B.,University of Caxias do Sul | Rech C.,Federal University of Santa Maria | Pinheiro J.R.,Federal University of Santa Maria
IEEE Transactions on Industrial Electronics | Year: 2010

This paper presents a comparison of three topologies of multilevel inverters applied to drive an induction motor of 500 kVA/4.16 kV rating. The multilevel inverters analyzed are the following: a neutral-point-clamped inverter, a symmetrical cascaded multilevel inverter, and a hybrid asymmetrical cascaded multilevel inverter. The performance indexes used in the comparison are total harmonic distortion, first-order distortion factor, second-order distortion factor, common-mode voltage, semiconductor power loss distribution, and heat-sink volume. The multilevel inverters are designed to present 99% efficiency at the nominal operating point, and the aforementioned performance indexes are compared for distinct values of amplitude modulation depth. © 2010 IEEE.

Mattos B.D.,Federal University of Pelotas | Misso A.L.,Federal University of Santa Maria | De Cademartori P.H.G.,Federal University of Paraná | De Lima E.A.,Embrapa Forestry | And 3 more authors.
Construction and Building Materials | Year: 2014

This study presents the preparation of polypropylene composites filled with mixtures of household waste of mate-tea and eucalypt particles and aims to increase the economic value chain of mate-tea. Filler mixtures in proportions ranging from 0% to 60% with a fixed PP matrix at 40% were prepared in order to evaluate only the effect of the filler on thermochemical, physical and mechanical properties and on the morphology. The main findings showed that the addition of filler from natural sources decreased thermal stability of composites, but that the temperature of crystallisation increased. Composites with a higher proportion of wood particles showed higher hydrophobic character; however, only the composites with 60% and 54% of mate-tea waste particles showed significantly higher results for water absorption. The use of eucalypt particles increased more mechanical properties than that of household waste, which proves its efficiency as filler. Nevertheless, the use of household waste also increased the properties of the final product and showed that it can be a good alternative for the use of renewable materials in the production of polymeric composites. © 2014 Elsevier Ltd. All rights reserved.

Barin A.,Federal University of Santa Maria | Canha L.,Federal University of Santa Maria | Abaide A.,Federal University of Santa Maria | MacHado R.,University of Sao Paulo
IEEE Latin America Transactions | Year: 2012

The Brazilian electric systems need the development of new researches and tools, in order to obtain a logic solution to maintain and improve the reliability and the quality of the power delivered to customers. The study of the appropriate connection of dispersed generation sources is an essential topic to be analyzed, since this process may provide positive impacts along the feeders. The main effects of the DG operation inside a distribution system model are here analyzed through the software DigSilent , considering power losses and voltage levels. Moreover, a multi-objective methodology - Bellman-Zadeh algorithm and membership fuzzy functions - is used for evaluating quantitative and qualitative parameters. The main objective of the paper is finding the appropriate DG placement inside a distribution system model. It is important to observe that the methodology presented in this study can be applied to distribution system feeders to find in which feeder will be the most appropriate DG location, as well to any node inside a determined feeder providing a specific place for the appropriate DG site. © 2012 IEEE.

Da Ros S.,Federal University of Santa Maria | Colusso G.,Federal University of Santa Maria | Weschenfelder T.A.,Federal University of Paraná | De Marsillac Terra L.,Federal University of Santa Maria | And 3 more authors.
Applied Soft Computing Journal | Year: 2013

Mathematical models in biochemical engineering field are usually composed by nonlinear kinetic equations, where the number of parameters that must be estimated from a set of experimental measurements is usually very high. In these cases, the estimation of the model parameters comprises numerical iterative methods for minimization of the objective function. Classical methods for minimization of the objective function, like the Newton method, requires a good initial guess for all parameters and differentiation of the objective function and/or model equations with respect to the model parameters. Besides, the use of stochastic optimization methods for parameter estimation has gained attention, since these methods do not require a good initial guesses of all model parameters and neither the evaluation of derivatives. In this work, some stochastic optimization methods (Artificial Bee Colony, Differential Evolution, Particle Swarm Optimization and Simulated Annealing) were used in the estimation of kinetic parameters of a biochemical model for an alcoholic fermentation of cassava hydrolyzed. The results indicated that Differential Evolution provides better results among the stochastic optimization methods evaluated. © 2013 Elsevier B.V.

Hourneaux Jr. F.,Nove de Julho University | Hrdlicka H.A.,Federal University of Paraiba | Gomes C.M.,Federal University of Santa Maria | Kruglianskas I.,University of Sao Paulo
Ecological Indicators | Year: 2014

Measuring environmental performance effectively has been a challenge for organizations. One crucial aspect for accomplish this task is the proper definition and use of environmental performance indicators (EPIs). The aim of this paper is to analyze the use of EPIs by industrial companies and to find out differences in the use of these indicators according to their characteristics and also to the size of the respondent companies. The study has as its basis the EPIs proposed by GRI (Global Reporting Initiative) Guidelines and was conducted through a survey. The sample reached 149 companies in industrial sector in Sao Paulo State, Brazil. The main results suggest different uses for EPIs, with an emphasis on those more directly linked to the productive direct costs and also have shown differences in their use between smaller and larger companies. © 2013 Elsevier Ltd. All rights reserved.

Marcelo M.C.A.,Federal University of Rio Grande do Sul | Martins C.A.,Federal University of Rio Grande do Sul | Pozebon D.,Federal University of Rio Grande do Sul | Dressler V.L.,Federal University of Santa Maria | And 2 more authors.
Microchemical Journal | Year: 2014

Yerba mate (Ilex paraguariensis), a widely consumed beverage in South America, is now also used worldwide. This study deals with a novel approach of characterization and identification of yerba mate. Fifty four samples of yerba mate from Argentina, Brazil, Paraguay and Uruguay were analyzed. A method was developed for determination of Al, Ba, Ca, Cu, Fe, K, Mg, Mn, P, Sr and Zn using inductively coupled plasma optical emission spectrometry (ICP OES), and Li, Be, Ti, V, Cr, Ni, Co, As, Se, Rb, Mo, Ag, Cd, Sb, La, Ce, Pb, Bi and U using inductively coupled plasma mass spectrometry (ICP-MS). Principal component analysis (PCA), k-nearest neighbor (KNN), soft independent modeling class analogy (SIMCA), partial least square discriminant analysis (PLS-DA), and support vector machine discriminant analysis (SVM-DA) were used for multivariate analysis of the element concentrations found, in order to classify the yerba mate according to the country of origin. For all analyzed samples, the classification was 100% correct by means of SVM-DA when all investigated and detected elements (24) were considered. © 2014 Elsevier B.V.

Romero-Gonzalez R.,University of Almeria | Garrido Frenich A.,University of Almeria | Martinez Vidal J.L.,University of Almeria | Prestes O.D.,Federal University of Santa Maria | Grio S.L.,National Autonomous University of Nicaragua, León
Journal of Chromatography A | Year: 2011

A method for the simultaneous determination of pesticides, biopesticides and mycotoxins from organic products was developed. Extraction of more than 90 compounds was evaluated and performed by using a modified QuEChERS-based (acronym of Quick, Easy, Cheap, Effective, Rugged, and Safe) sample preparation procedure. The method was based on a single extraction with acidified acetonitrile, followed by partitioning with salts, avoiding any clean-up step prior the determination by ultra-high performance liquid chromatography/tandem quadrupole mass spectrometry (UHPLC-MS/MS). Validation studies were carried out in wheat, cucumber and red wine as representative matrixes. Recoveries of the spiked samples were in the range between 70 and 120% (with intra-day precision, expressed as relative standard deviation, lower than 20%) for most of the analysed compounds, except picloram and quinmerac. Inter-day precision, expressed as relative standard deviation, was lower than 24%. Limits of quantification were lower than 10μgkg-1 and the developed method was successfully applied to the analysis of organic food products, detecting analytes belonging to the three types of compounds. © 2011 Elsevier B.V.

Montenegro M.F.,University of Sao Paulo | Amaral J.H.,University of Sao Paulo | Pinheiro L.C.,University of Campinas | Sakamoto E.K.,University of Sao Paulo | And 5 more authors.
Free Radical Biology and Medicine | Year: 2011

Dietary nitrite and nitrate are important sources of nitric oxide (NO). However, the use of nitrite as an antihypertensive drug may be limited by increased oxidative stress associated with hypertension. We evaluated the antihypertensive effects of sodium nitrite given in drinking water for 4 weeks in two-kidney one-clip (2K1C) hypertensive rats and the effects induced by nitrite on NO bioavailability and oxidative stress. We found that, even under the increased oxidative stress conditions present in 2K1C hypertension, nitrite reduced systolic blood pressure in a dose-dependent manner. Whereas treatment with nitrite did not significantly change plasma nitrite concentrations in 2K1C rats, it increased plasma nitrate levels significantly. Surprisingly, nitrite treatment exerted antioxidant effects in both hypertensive and sham-normotensive control rats. A series of in vitro experiments was carried out to show that the antioxidant effects induced by nitrite do not involve direct antioxidant effects or xanthine oxidase activity inhibition. Conversely, nitrite decreased vascular NADPH oxidase activity. Taken together, our results show for the first time that nitrite has antihypertensive effects in 2K1C hypertensive rats, which may be due to its antioxidant properties resulting from vascular NADPH oxidase activity inhibition. © 2011 Elsevier Inc. All rights reserved.

Stringhini F.M.,Federal University of Santa Maria | Foletto E.L.,Federal University of Santa Maria | Sallet D.,Federal University of Santa Maria | Bertuol D.A.,Federal University of Santa Maria | And 2 more authors.
Journal of Alloys and Compounds | Year: 2014

Zinc aluminate (ZnAl2O4) particles with a spinel structure were prepared by metal-chitosan complexation method. The solids were obtained by the thermal decomposition of precursor compound of metallic hydroxides mixture and the biopolymer chitosan. X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and N2-adsorption-desorption isotherms were used for the characterization of the products. The results showed that the ZnAl2O4 spinel can be obtained by heating the precursor at temperatures above of 500 C, resulting in a material with porous structure and large surface area and high purity. © 2013 Elsevier Ltd. All rights reserved.

Sargenti S.R.,University of Sao Paulo | Almeida C.A.A.,Federal University of Santa Maria
Ecletica Quimica | Year: 2010

The goal of this work was to develop a simple and rapid preparation method for patulin analysis in apple juice without previous clean-up. This method combined sonication and liquid extraction techniques and was used for determination of patulin in 37 commercial apple juices available on the market in the South of Brazil. The method performance characteristics were determined using a sample obtained in a local market fortified at five concentration levels of patulin and done in triplicates. The coefficient of variation for repeatability at the fortification level of 20.70μg.L-1 was 3.53 % and the recovery 94.63 %, respectively. The correlation coefficient was 0.9996 and agrees with the requirements for a linear analytical method value. The detection limit was 0.21μg.L-1 and the quantification limit 0.70 μg.L-1. Only three of the analyzed samples were upper the allowed level of 50.00 μg.L-1 recommended for the World Health Organization.

Piovesan C.,University of Sao Paulo | Ardenghi T.M.,Federal University of Santa Maria | Guedes R.S.,Federal University of Santa Maria | Ekstrand K.R.,Copenhagen University | And 2 more authors.
Community Dentistry and Oral Epidemiology | Year: 2013

Objectives This study aimed to evaluate the magnitude of the reduction in caries parameters after inclusion of dental caries activity assessment, in an epidemiological survey of preschool children, involving cavitated and noncavitated caries lesions. Methods The survey was carried out in Santa Maria, Brazil, during the National Children's Vaccination Day, and 639 children aged between 12 months and 59 months were included. Fifteen examiners assessed the children based on the International Caries Detection and Assessment System (ICDAS) and additional lesion activity assessment criteria. The mean of decayed surfaces (d-s), the mean of decayed teeth (d-t), caries prevalence, and 95% confidence intervals were calculated, initially by classifying all lesions using the various thresholds defined by the ICDAS. Caries activity status was then evaluated, and inactive lesions were classified as sound in a secondary analysis; subsequently, the same caries parameters, at the same thresholds, were recalculated. The reduction in caries parameters and the number of children requiring assessment to change their classification from decayed to sound (number needed to be assessed) were also calculated. Results The majority of lesions were classified as active, mainly at cavitated thresholds. When activity was considered, values of all caries parameters decreased. This decrease was more evident at noncavitated thresholds. The number of children requiring assessment to change their classification from decayed to sound was <20 considering all lesions, but this value increased to approximately 100 when we included only cavitated lesions. Conclusions The inclusion of activity assessment in caries epidemiological surveys has little impact on the d-s, d-t and prevalence of dental caries considering both noncavitated and cavitated lesions. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

De Jong van Lier Q.,University of Sao Paulo | Gubiani P.I.,Federal University of Santa Maria
Revista Brasileira de Ciencia do Solo | Year: 2015

As opposed to objective definitions in soil physics, the subjective term “soil physical quality” is increasingly found in publications in the soil physics area. A supposed indicator of soil physical quality that has been the focus of attention, especially in the Brazilian literature, is the Least Limiting Water Range (RLL), translated in Portuguese as “Intervalo Hídrico Ótimo” or IHO. In this paper the four limiting water contents that define RLL are discussed in the light of objectively determinable soil physical properties, pointing to inconsistencies in the RLL definition and calculation. It also discusses the interpretation of RLL as an indicator of crop productivity or soil physical quality, showing its inability to consider common phenological and pedological boundary conditions. It is shown that so-called “critical densities” found by the RLL through a commonly applied calculation method are questionable. Considering the availability of robust models for agronomy, ecology, hydrology, meteorology and other related areas, the attractiveness of RLL as an indicator to Brazilian soil physicists is not related to its (never proven) effectiveness, but rather to the simplicity with which it is dealt. Determining the respective limiting contents in a simplified manner, relegating the study or concern on the actual functioning of the system to a lower priority, goes against scientific construction and systemic understanding. This study suggests a realignment of the research in soil physics in Brazil with scientific precepts, towards mechanistic soil physics, to replace the currently predominant search for empirical correlations below the state of the art of soil physics. © 2015, Revista Brasileira de Ciencia do Solo. All rights reserved.

Venzke D.,Federal University of Pelotas | Flores A.F.C.,Federal University of Santa Maria | Quina F.H.,University of Sao Paulo | Pizzuti L.,Federal University of Grande Dourados | And 3 more authors.
Ultrasonics Sonochemistry | Year: 2011

A rapid and cleaner procedure for the synthesis of a series of 2-(3,5-diaryl-4,5-dihydro-1. H-pyrazol-1-yl)-4-phenylthiazoles under ultrasonic irradiation in ethanol is described. © 2010 Elsevier B.V.

Dilkin P.,Federal University of Santa Maria | Direito G.,Federal Rural University of Rio de Janeiro | Simas M.M.S.,University of Sao Paulo | Mallmann C.A.,Federal University of Santa Maria | Correa B.,University of Sao Paulo
Chemico-Biological Interactions | Year: 2010

Toxicokinetics and the toxicological effects of culture material containing fumonisin B1 (FB1) were studied in male weaned piglets by clinical, pathological, biochemical and sphingolipid analyses. The animals received a single oral dose of 5mgFB1/kg of body weight, obtained from Fusarium verticillioides culture material. FB1 was detected by HPLC in plasma collected at 1-h intervals up to 6h and at 12-h intervals up to 96h. FB1 eliminated in feces and urine was quantified over a 96-h period and in liver samples collected 96h post-intoxication. Blood samples were obtained at the beginning and end of the experiment to determine serum enzyme activity, total bilirubin, cholesterol, sphinganine (Sa), sphingosine (So) and the Sa/So ratio. FB1 was detected in plasma between 30min and 36h after administration. The highest concentration of FB1 was observed after 2h, with a mean concentration of 282μg/ml. Only 0.93% of the total FB1 was detected in urine between 75min and 41h after administration, the highest mean concentration (561μg/ml) was observed during the interval after 8 at 24h. Approximately 76.5% of FB1 was detected in feces eliminated between 8 and 84h after administration, with the highest levels observed between 8 and 24h. Considering the biochemical parameters, a significant increase only occurred in cholesterol, alkaline phosphatase and aspartate aminotransferase activities. In plasma and urine, the highest Sa and Sa/So ratios were obtained at 12 and 48h, respectively. © 2010 Elsevier Ireland Ltd.

Perussello C.A.,Federal University of Paraná | Mariani V.C.,Pontifical Catholic University of Parana | Masson M.L.,Federal University of Paraná | Castilhos F.D.,Federal University of Santa Maria
International Journal of Heat and Mass Transfer | Year: 2013

Thermophysical properties of yacon (Smallanthus sonchifolius) - specific mass, specific heat and thermal conductivity - were obtained experimentally at 30 min intervals in order to model and simulate the mass and heat transfer phenomena involved in a drying process. Thermal diffusivity was calculated using the former properties. Empirical models obtained by nonlinear regression were successfully fitted to the thermophysical properties rates. Using the data of thermophysical properties in function of moisture content, the theoretical drying model was simulated and validated by the experimental results of yacon's moisture content and temperature, providing determination coefficients higher than 0.97. © 2013 Elsevier Ltd. All rights reserved.

Alva G.M.S.,Federal University of Santa Maria | El Debs A.L.H.D.C.,University of Sao Paulo
Engineering Structures | Year: 2013

This paper presents experimental results on the moment-rotation behavior of reinforced concrete beam-column connections as well as a simple analytical model to predict this curve for structural design purposes. The parameters considered by the proposed model are the relative slip of the flexural reinforcement in the joint and the slip induced by flexural cracking of the beam end. A new procedure based on the evaluation of the crack width inside disturbed regions (D-regions) was used to calculate the rotation resulting from the cracking of the beam. Adaptations and simplifications were performed aiming to turn the analytical model suitable for numerical modeling of the non-linear behavior of reinforced concrete frames. The moment-rotation curves given by the proposed model were compared to the experimental curves given by the tests. Additionally, the proposed curves were included in a software program based on the finite element method, allowing comparisons between theoretical and experimental results for vertical displacements of the beams. The obtained results showed a good agreement with the tests. © 2013 Elsevier Ltd.

Piotrowski M.J.,Federal University of Santa Maria | Piquini P.,Federal University of Santa Maria | Da Silva J.L.F.,University of Sao Paulo
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

The knowledge of the atomic structure of clusters composed by few atoms is a basic prerequisite to obtain insights into the mechanisms that determine their chemical and physical properties as a function of diameter, shape, surface termination, as well as to understand the mechanism of bulk formation. Due to the wide use of metal systems in our modern life, the accurate determination of the properties of 3d, 4d, and 5d metal clusters poses a huge problem for nanoscience. In this work, we report a density functional theory study of the atomic structure, binding energies, effective coordination numbers, average bond lengths, and magnetic properties of the 3d, 4d, and 5d metal (30 elements) clusters containing 13 atoms, M13. First, a set of lowest-energy local minimum structures (as supported by vibrational analysis) were obtained by combining high-temperature first-principles molecular-dynamics simulation, structure crossover, and the selection of five well-known M13 structures. Several new lower energy configurations were identified, e.g., Pd13, W13, Pt13, etc., and previous known structures were confirmed by our calculations. Furthermore, the following trends were identified: (i) compact icosahedral-like forms at the beginning of each metal series, more opened structures such as hexagonal bilayerlike and double simple-cubic layers at the middle of each metal series, and structures with an increasing effective coordination number occur for large d states occupation. (ii) For Au13, we found that spin-orbit coupling favors the three-dimensional (3D) structures, i.e., a 3D structure is about 0.10 eV lower in energy than the lowest energy known two-dimensional configuration. (iii) The magnetic exchange interactions play an important role for particular systems such as Fe, Cr, and Mn. (iv) The analysis of the binding energy and average bond lengths show a paraboliclike shape as a function of the occupation of the d states and hence, most of the properties can be explained by the chemistry picture of occupation of the bonding and antibonding states. © 2010 The American Physical Society.

Muller A.S.,Federal University of Rio Grande do Sul | Storchi-Bergmann T.,Federal University of Rio Grande do Sul | Riffel R.A.,Federal University of Santa Maria | Ferrari F.,Federal University of Pampa | And 4 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2011

We present two-dimensional stellar and gaseous kinematics of the inner 120×250 pc 2 of the LINER/Seyfert 1 galaxy M81, from optical spectra obtained with the Gemini Multi-Object Spectrograph (GMOS) integral field spectrograph on the Gemini-North telescope at a spatial resolution of ≈10 pc. The stellar velocity field shows circular rotation and, overall, is very similar to the published large-scale velocity field, but deviations are observed close to the minor axis which can be attributed to stellar motions possibly associated with a nuclear bar. The stellar velocity dispersion of the bulge is 162±15 km s -1, in good agreement with previous measurements and leading to a black hole mass of MBH =5.5 + -2.0 3.6 × 10 7M · based on the M BH-σ relationship. The gas kinematics is dominated by non-circular motions and the subtraction of the stellar velocity field reveals blueshifts of ≈-100 km s -1 on the far side of the galaxy and a few redshifts on the near side. These characteristics can be interpreted in terms of streaming towards the centre if the gas is in the plane. On the basis of the observed velocities and geometry of the flow, we estimate a mass inflow rate in ionized gas of ≈4.0×10 -3M · yr -1, which is of the order of the accretion rate necessary to power the LINER nucleus of M81. We have also applied the technique of principal component analysis (PCA) to our data, which reveals the presence of a rotating nuclear gas disc within ≈50 pc from the nucleus and a compact outflow, approximately perpendicular to the disc. The PCA combined with the observed gas velocity field shows that the nuclear disc is being fed by gas circulating in the galaxy plane. The presence of the outflow is supported by a compact jet seen in radio observations at a similar orientation, as well as by an enhancement of the [OI]/Hα line ratio, probably resulting from shock excitation of the circumnuclear gas by the radio jet.With these observations we are thus resolving both the feeding, via the nuclear disc and observed gas inflow, and the feedback, via the outflow, around the low-luminosity active nucleus of M81. © 2011 The Authors. Monthly Notices of the Royal Astronomical Society © 2011 RAS.

Piotrowski M.J.,Federal University of Santa Maria | Piquini P.,Federal University of Santa Maria | Zeng Z.,CAS Dalian Institute of Chemical Physics | Zeng Z.,Technical University of Denmark | And 2 more authors.
Journal of Physical Chemistry C | Year: 2012

The adsorption of NO on transition-metal (TM) surfaces has been widely studied by experimental and theoretical techniques; however, our atomistic understanding of the interaction of nitrogen monoxide (NO) with small TM clusters is far from satisfactory, which compromises a deep understanding of real catalyst devices. In this study, we report a density functional theory study of the adsorption properties of NO on the TM 13 (TM = Rh, Pd, Ir, Pt) clusters employing the projected augmented wave method. We found that the interaction of NO with TM 13 is much more complex than that for NO/TM(111). In particular, for low symmetry TM 13 clusters, there is a strong rearrangement of the electronic charge density upon NO adsorption and, as a consequence, the adsorption energy shows a very complex dependence even for adsorption sites with the same local effective coordination. We found a strong enhancement of the binding energy of NO to the TM 13 clusters compared with the TM(111) surfaces, as the antibonding NO states are not occupied for NO/TM 13, and the general relationship based on the d-band model between adsorption energy and the center of gravity of the occupied d-states does not hold for the studied TM 13 clusters, in particular, for clusters with low symmetry. In contrast with the adsorption energy trends, the geometric NO/TM 13 parameters and the vibrational N-O frequencies for different coordination sites follow the same trend as for the respective TM(111) surfaces, while the changes in the frequencies between different surfaces and TM 13 clusters reflect the strong NO-TM 13 interaction. © 2012 American Chemical Society.

Piotrowski M.J.,Federal University of Santa Maria | Piquini P.,Federal University of Santa Maria | Da Silva J.L.F.,University of Sao Paulo
Journal of Physical Chemistry C | Year: 2012

Structural and electronic properties of the Pt nTM 55-n (TM = Co, Rh, Au) nanoalloys are investigated using density functional theory within the generalized gradient approximation and employing the all-electron projected augmented wave method. For TM = Co and Rh, the excess energy, which measures the relative energy stability of the nanoalloys, is negative for all Pt compositions. We found that the excess energy has similar values for a wide range of Pt compositions, i.e., n = 20-42 and n = 28-42 for Co and Rh, respectively, with the core-shell icosahedron-like configuration (n = 42) being slightly more stable for both Co and Rh systems because of the larger release of the strain energy due to the smaller atomic size of the Co and Rh atoms. For TM = Au, the excess energy is positive for all compositions, except for n = 13, which is energetically favorable due to the formation of the core-shell structure (Pt in the core and Au atoms at the surface). Thus, our calculations confirm that the formation of core-shell structures plays an important role to increase the stability of nanoalloys. The center of gravity of the occupied d-states changes almost linearly as a function of the Pt composition, and hence, based on the d-band model, the magnitude of the adsorption energy of an adsorbate can be tuned by changing the Pt composition. The magnetic moments of Pt nCo 55-n decrease almost linearly as a function of the Pt composition; however, the same does not hold for PtRh and PtAu. We found an enhancement of the magnetic moments of PtRh by a few times by increasing Pt composition, which we explain by the compression effects induced by the large size of the Pt atoms compared with the Rh atoms. © 2012 American Chemical Society.

de Lima C.L.R.,Federal University of Pelotas | Miola E.C.C.,Federal University of Santa Maria | Timm L.C.,Federal University of Pelotas | Pauletto E.A.,Federal University of Pelotas | da Silva A.P.,University of Sao Paulo
Soil and Tillage Research | Year: 2012

The use of cover crops affects the support capacity of soil and least limiting water range to crop growth. The objective of this study was to quantify preconsolidation pressure (σ p), compression index (CI) and least limiting water range (LLWR) of a reclaimed coal mining soil under different cover crops, in Candiota, RS, Brazil. In the experiment, with randomized blocks design and four replicates, the following cover crops (treatments) were evaluated: Hemarthria altissima (Poir.) Stapf & C.E. Hubbard, treatment 1 (T1), Paspalum notatum Flüggé, treatment 4 (T4), Cynodon dactilon (L.) Pers., treatment 5 (T5), control Brachiaria brizantha (Hochst.) Stapf, treatment 7 (T7) and without cover crop treatment 8 (reference treatment, T8). Soil compression and least limiting water range were evaluated with undisturbed samples at a depth of 0.00-0.05m. In order to evaluate parameters of soil compressibility, the soil samples were saturated with water and subjected to -10kPa matric potential and then submitted to a uniaxial compression test under the following pressures: 25, 50, 100, 200, 400, 800 and 1600kPa. Cover crops decreased the preconsolidation pressure of constructed soils after coal mining and the greatest soil reclamation was obtained with the H. altissima cover crop, where the lowest degree of soil compactness and soil load capacity were observed. Soils cultivated under H. altissima or B. brizantha presented the highest least limiting water range and these two cover crops generated similar soil critical bulk density obtained by least limiting water range and soil load support capacity. © 2012 Elsevier B.V.

Kalempa D.,Federal University of Santa Maria | Sharipov F.,Federal University of Paraná
European Journal of Mechanics, B/Fluids | Year: 2011

An approach to a model of rarefied gaseous mixtures with a low mole fraction of one species based on the linearized Boltzmann equation is proposed. As an example, the separation phenomenon in a binary gaseous mixture flowing through a long tube into a vacuum is considered by assuming an arbitrary pressure at the tube's entrance. In this situation, the regime of gas flow along the tube can vary from hydrodynamic to free molecular. The calculations were carried out for a mixture of HeliumXenon considering two limits, first when the mole fraction of Helium is low and second when the mole fraction of Xenon is low. As a result, flow rates of each species and their density distributions along the tube are calculated in a wide range of gas rarefaction in the tube inlet. The advantages of the present methodology in comparison to that developed previously for an arbitrary mole fraction are pointed out. © 2011 Elsevier Masson SAS. All rights reserved.

Ortiz R.,University of Sao Paulo | Copetti M.V.F.,Federal University of Santa Maria | Lorenz-Martins S.,Federal University of Rio de Janeiro
Monthly Notices of the Royal Astronomical Society | Year: 2011

Some of the most successful statistical methods for obtaining distances of planetary nebulae (PNe) are based on their apparent sizes and radio emission intensities. These methods have the advantage of being 'extinction free' and are especially suited to be applied to PNe situated at large distances. A similar method, based on the mid-infrared (MIR) emission of PNe, would have the advantage of being applicable to the large data bases created after the various all-sky or Galactic plane infrared surveys, such as IRAS, MSX, ISOGAL, GLIMPSE, etc. In this work we propose a statistical method to calculate the distance of PNe based on the apparent nebular radius and the MIR flux densities. We show that the specific intensity between 8 and 21 is proportional to the brightness temperatureTb at 5 GHz. Using MIR flux densities at 8, 12, 15 and 21 from the MSX survey, we calibrate the distance scale with a statistical method by Stanghellini, Shaw & Villaver (SSV). The data base used in the calibration consisted of 67 Galactic PNe with MSX counterparts and distances determined by SSV. We apply the method to a sample of PNe detected at 8 in the GLIMPSE infrared survey, and determine the distance of a sample of PNe located along the Galactic plane and bulge. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.

Wrasse E.O.,Federal University of Santa Maria | Baierle R.J.,Federal University of Santa Maria | Fazzio A.,University of Sao Paulo | Schmidt T.M.,Federal University of Uberlandia
Physical Review B - Condensed Matter and Materials Physics | Year: 2013

Fully relativistic calculations are used to perform a systematic study on the energetic stability, and electronic properties of group III (Al, Ga, In, and Tl) impurities in the cation-site (Pb) of PbSe: bulk and nanowire (NW). Our results show that group III impurities have lower formation energies in the NW than in the bulk. The impurities are site-dependent in the nanowires: they are more stable on the surface of the NW as compared to the core. In the bulk, Al and In are donor levels, while Ga and Tl are acceptor impurities. For the NW, the same trend is obtained for Al and Tl, whereas Ga and In are deep donors. A two-level model based on the interaction between the impurity states and the host crystalline field explains the electronic properties of group III impurity doped PbSe bulk and NW. This model agrees with the projected density of states and helps us to understand the unexpected n-type character of some group III impurity doped PbSe. © 2013 American Physical Society.

Mendes F.M.,University of Sao Paulo | Braga M.M.,University of Sao Paulo | Oliveira L.B.,University of Sao Paulo | Antunes J.L.F.,University of Sao Paulo | And 2 more authors.
Community Dentistry and Oral Epidemiology | Year: 2010

Objectives: The aim of this cross-sectional study in preschool children was to assess the ability of International Caries Detection and Assessment System (ICDAS) in discriminating socioeconomic factors associated with the presence of caries lesions at both noncavitated and cavitated thresholds and to compare with the standard World Health Organization (WHO) criteria. Methods: The study was carried out in Amparo, Brazil, during the National Day of Children's Vaccination including 252 children aged 36-59 months. The same child was independently examined by two calibrated examiners, one using the ICDAS and the other using WHO criteria. Socioeconomic information was also recorded. Associations between socioeconomic factors and presence of caries assessed as binary (caries prevalence) and count outcome (actual dmfs values) obtained by WHO criteria and by ICDAS at noncavitated and cavitated thresholds were evaluated by Poisson regression analysis with robust variance. Results: Some covariates were significantly associated with the presence of caries evaluated by the WHO criteria and by ICDAS (using score 3 as cut-off point). When noncavitated scores of ICDAS were used to calculate the presence of caries, the discriminant power decreased. When dmfs values were used as outcome, no differences in the associations were observed between two systems or using noncavitated caries lesions. Conclusion: Cavitated scores of ICDAS present similar discriminant validity compared with WHO criteria when presence of caries is used as outcome; however, when actual dmfs values are used, no differences are observed in using noncavitated or cavitated caries lesions. © 2010 John Wiley & Sons A/S.

Piotrowski M.J.,Federal University of Santa Maria | Piquini P.,Federal University of Santa Maria | Candido L.,Federal University of Goais | Da Silva J.L.F.,University of Sao Paulo
Physical Chemistry Chemical Physics | Year: 2011

The crystalline structure of transition-metals (TM) has been widely known for several decades, however, our knowledge on the atomic structure of TM clusters is still far from satisfactory, which compromises an atomistic understanding of the reactivity of TM clusters. For example, almost all density functional theory (DFT) calculations for TM clusters have been based on local (local density approximation - LDA) and semilocal (generalized gradient approximation - GGA) exchange-correlation functionals, however, it is well known that plain DFT fails to correct the self-interaction error, which affects the properties of several systems. To improve our basic understanding of the atomic and electronic properties of TM clusters, we report a DFT study within two nonlocal functionals, namely, the hybrid HSE (Heyd, Scuseria, and Ernzerhof) and GGA+U functionals, of the structural and electronic properties of the Co 13, Rh 13, and Hf 13 clusters. For Co 13 and Rh 13, we found that improved exchange-correlation functionals decrease the stability of open structures such as the hexagonal bilayer (HBL) and double simple-cubic (DSC) compared with the compact icosahedron (ICO) structure, however, DFT-GGA, DFT-GGA+U, and DFT-HSE yield very similar results for Hf 13. Thus, our results suggest that the DSC structure obtained by several plain DFT calculations for Rh 13 can be improved by the use of improved functionals. Using the sd hybridization analysis, we found that a strong hybridization favors compact structures, and hence, a correct description of the sd hybridization is crucial for the relative energy stability. For example, the sd hybridization decreases for HBL and DSC and increases for ICO in the case of Co 13 and Rh 13, while for Hf 13, the sd hybridization decreases for all configurations, and hence, it does not affect the relative stability among open and compact configurations. © 2011 the Owner Societies.

Anchieta C.G.,Federal University of Santa Maria | Sallet D.,Federal University of Santa Maria | Foletto E.L.,Federal University of Santa Maria | Da Silva S.S.,Federal University of Rio Grande do Norte | And 2 more authors.
Ceramics International | Year: 2014

Ternary zinc spinel oxides such as Zn2SnO4, ZnAl 2O4 and ZnFe2O4 were synthesized and characterized, and their activities in the photodegradation of phenol molecules were investigated. Zn2SnO4, ZnAl2O4 and ZnFe2O4 powders were synthesized by hydrothermal, metal-chitosan complexation and solvothermal routes, respectively. The face-centered cubic spinel structure of each material was confirmed by powder X-ray diffractometry (XRD) and its porous structure by N2 adsorption-desorption isotherms. The characterization of spinels was complemented with Fourier transform infrared spectroscopy (FTIR) and X-rays fluorescence (XRF), revealing the formation of spinel structures with high purity. The photocatalytic activity in the degradation of phenol was observed only with Zn2SnO4 oxide. Mineralization degree of phenol molecules by Zn2SnO4 photocatalyst determined by total organic carbon analysis (TOC) reached 80% at 360 min under sunlight. © 2013 Elsevier Ltd and Techna Group S.r.l.

This study had the aim to verify the necessities of training and improvement of the 4th Regional Coordination in Health of Rio Grande do Sul State family health teams. The data collection was carried out through the application of questionnaires with objective questions, composed by two parts: field and competence nucleus. For data analyses, Normality, Chi-Square and G tests were used as statistical procedures for Easy and Difficult attributions indicated by the professionals. Professionals have shown less difficulty with generic attributions, related with basic methods and techniques of each health area. However, they have revealed a lot of difficulties with attributions relating to the search of new partners in health inside communities, stimulation of the people participation in the discussion of health rights, and completion of the SIA/SIAB forms, and others. Even after 12 years of the foundation of the Family Health Program (PSF), several difficulties are still observed concerning the way to work with this new health strategy in Brazil. Proposals are made for the complete understanding and improvement of the PSF strategy.

Magnago T.S.B.S.,Federal University of Santa Maria | Lisboa M.T.L.,Federal University of Rio de Janeiro | Griep R.H.,Laboratorio Of Educacao Saude E Ambiente | Kirchhof A.L.C.,Federal University of Paraná | Guido L.A,Federal University of Santa Maria
Revista Latino-Americana de Enfermagem | Year: 2010

This study aimed to evaluate the association between psychological demands and control on work and the occurrence of musculoskeletal disorders among nursing workers. This cross-sectional study involved 491 nursing workers from a University hospital in Rio Grande do Sul. Brazilian versions of the Nordic Musculoskeletal Questionnaire and the Job Content Questionnaire were used. Among the participants, 96.3% reported some pain in any given part of the body last year, 73.1% in the last seven days and 65.8% reported difficulty in their daily routine. The chances of shoulder pain (OR=1.97; CI95%=1.07-3.64), in the thoracic spine (OR=1.83; CI95%=1.02-3.35) and in the ankles (OR=2.05; CI95%=1.05-4.02) were higher in the high work demand quadrant when compared to the low demand quadrant, after adjustments for potentially confusing factors Intervention measures in the organizational structure are needed, redefining demand levels and control at work.

Konig R.,Federal University of Santa Maria | Konig R.,Instituto Federal Farroupilha Campus Julio Of Castilhos | Hepp L.U.,URI Integrated Regional University Brazil | Santos S.,Federal University of Santa Maria
Limnologica | Year: 2014

Leaf litter in streams is exploited by benthic macroinvertebrates, and leaf traits may influence colonisation by this group. This study aimed to compare the leaf decomposition rates, structure, and composition of the macroinvertebrate fauna colonising the litter of plant species with contrasting leaf traits. Litter bags from two native plant species (Sebastiania brasiliensis and Campomanesia xanthocarpa) and two non-natives (Hovenia dulcis and Platanus×. acerifolia) were incubated in a subtropical stream. After 7, 14, 21, and 28 days, four leaf bags for each species were removed, and the leaf decomposition rates, density of organisms and trophic guilds, taxonomic richness, and functional composition of the macroinvertebrates were compared. The decomposition rates and densities of organisms, shredders, and collector-gatherers were higher for the leaves considered to be better quality, with lower C:N and Lignin:N ratios (from S. brasiliensis and H. dulcis). Additionally, the taxonomic and functional compositions of the macroinvertebrates were different for these leaves. In contrast, the species richness and density of the other guilds showed no significant difference between species. This study shows that detritivorous groups prefer leaves of better quality, and most results may be influenced by the high nutritional content and low amount of compounds that complicate fragmentation, such as tannins, lignin, and cellulose. Therefore, the effects of the replacement of riparian plant species on the local macrofauna depend of the traits of the introduced and replaced plant, regardless of their origin. © 2013 Elsevier GmbH.

Gonzales G.B.,Ghent University | Smagghe G.,Ghent University | Grootaert C.,Ghent University | Zotti M.,Ghent University | And 3 more authors.
Drug Metabolism Reviews | Year: 2015

Flavonoids are a group of polyphenols that provide health-promoting benefits upon consumption. However, poor bioavailability has been a major hurdle in their use as drugs or nutraceuticals. Low bioavailability has been associated with flavonoid interactions at various stages of the digestion, absorption and distribution process, which is strongly affected by their molecular structure. In this review, we use structure-activity/property relationship to discuss various flavonoid interactions with food matrices, digestive enzymes, intestinal transporters and blood proteins. This approach reveals specific bioactive properties of flavonoids in the gastrointestinal tract as well as various barriers for their bioavailability. In the last part of this review, we use these insights to determine the effect of different structural characteristics on the overall bioavailability of flavonoids. Such information is crucial when flavonoid or flavonoid derivatives are used as active ingredients in foods or drugs. © 2015 Informa Healthcare USA, Inc.

Marchesan E.,Federal University of Santa Maria | Senseman S.A.,Texas AgriLife Research Center
Ciencia Rural | Year: 2010

In agriculture, there is a difference between average yield obtained by farmers and crop potential. There is technology available to increase yields, but not all farmers have access to it and/or use this information. This clearly characterizes an extension and technology transference problem. There are several technology transfer systems, but there is no system to fit all conditions. Therefore, it is necessary to create extension solutions according to local conditions. Another rural extension challenge is efficiency, despite continuous funding reductions. One proposal that has resulted from extension reform worldwide has suggested integration between the public and private sectors. The public universities could play the role of training and updating technical assistance of human resources, which is the one of the main aspects that has limited technology transfer. The objective of this study was to identify approaches to promote technology transfer generated in Brazilian public universities to rural areas through literature review. An experimental approach of technology transfer is presented here where a Brazilian university extension Vice-chancellor incorporates professionals from consolidated research groups according to demand. In this way, public universities take part of their social functions, by integrating teaching, research, and extension.

Soares K.P.,Federal University of Santa Maria | Pimenta R.S.,Tropical Plantas e Paisagismo | Guimaraes C.A.,Rua Carneiro da Rocha
Ciencia Florestal | Year: 2013

Two new species of Syagrus Mart. (Arecaceae) from Brazil are described and illustrated in this article: first, Syagrus pompeoi K. Soares & R. Pimenta, a species related to Syagrus procumbens Noblick & Lorenzi, from which it differs by having a caespitose habit, by the greater length of the rachis of leaves (33-50 cm), more pinnae on each side (8-15), leaflet almost membranaceous with many transverse ribs visible, as well as longer inflorescence peduncle (10 to 18 cm). The second one, Syagrus santosii K. Soares & C. A. Guim., related to Syagrus schyzophylla (Mart.) Becc., from which it differs by having larger fruit (2.9 to 4.6 x 2.6 to 3.8 cm), with epicarp and mesocarp usually split at the apex when ripe, bigger endocarp (2.7 to 4.2 x 2.4 to 3 cm) with homogeneous endosperm, greater amount of pinnae on each side of the leaf and larger pistillate flowers.

Vasconcelos S.S.,University of Florida | Zarin D.J.,University of Florida | Araujo M.M.,Federal University of Santa Maria | Miranda I.D.S.,University of Amazon
Forest Ecology and Management | Year: 2012

Aboveground net primary productivity (ANPP) represents an important integrated measure of resource effects on forest ecosystem functions. Rates of ANPP, as well as resource availability controls over ANPP, are poorly understood for tropical forest regrowth following agricultural abandonment, although such regrowth accounts for a large and growing proportion of tropical landscapes. Here, we report on the response of ANPP to inter-annual variability in dry-season precipitation and to four years of dry-season irrigation in a forest regrowth stand in eastern Amazonia. ANPP was most strongly correlated with previous-year annual and dry-season precipitation inputs, suggesting a lag effect of the influence of precipitation on ANPP. The dry-season irrigation experiment provides some confirmation of this lag effect: ANPP response to treatment was significant for 2002 and 2003, following strong previous-year dry seasons, but not during the first treatment year (2001) or 2004, following the weak 2003 dry season. ANPP response to both inter-annual precipitation variability and to dry-season was largely due to a response in aboveground biomass increment rather than litterfall. Drought constraints on aboveground biomass increment suggest that the potential of forest regrowth to sequester atmospheric carbon will decrease with projected reductions in regional rainfall. © 2012 Elsevier B.V.

Souza A.F.,Federal University of Rio Grande do Norte | Cortez L.S.R.,University of the Rio dos Sinos Valley | Longhi S.J.,Federal University of Santa Maria
Biodiversity and Conservation | Year: 2012

If logging and forest multiple-use are to be compatible with biodiversity conservation, then forest structure, composition and diversity must be expected to recover from the disturbance and eventually return to their former levels. Here we evaluate the long-term effects of selective logging and forest multiple-use on Southern Brazilian subtropical Araucaria mixed conifer-hardwood forest resilience at the landscape-scale. Long-term effects of different management regimes were compared between control undisturbed forests and forest stands subjected to early (55 years before this study) and recent (13 years) selective logging followed by undisturbed postharvest periods, and forest fragments subjected to selective logging followed by unregulated multiple-use by private landowners. Forest structure (tree density, basal area and height, and regeneration density) in early-logged areas was indistinguishable from control areas. Fragmentation and chronic disturbance, however, degraded forest fragments and kept them at early successional stages, with higher tree density, reduced basal area and scarce or absent regeneration. Mixed forests showed compositional resilience in the angiosperm component but not in the conifer component. Chronic disturbance kept forest fragments floristically away from mature and undisturbed secondary forests. Species richness in control and recently-logged plots did not differ significantly and was higher than richness in early-logged plots. Species richness was much reduced in degraded forest fragments. Density of the conifer Araucaria angustifolia, characteristic of the mature forest, was reduced in the fragments and in logged stands. We discuss how native forest management practices can be implemented to contribute positively to the conservation of the Araucaria mixed forest biodiversity. © 2012 Springer Science+Business Media B.V.

Oliveira T.A.,Federal University of Santa Maria | Koakoski G.,Federal University of Santa Maria | da Motta A.C.,University Of Passo Fundo | Piato A.L.,Chapecó Region Community University | And 3 more authors.
Hormones and Behavior | Year: 2014

Living animals exploit information released from dead animals to conduct adaptive biological responses. For instance, a recently published study has shown that avoidance behavior is triggered by death-associated odors in zebrafish. Stress can clearly act as an adaptive response that allows an organism to deal with an imminent threat. However, it has not been demonstrated whether these chemical cues are stressful for fish. Here, we confirmed that dead zebrafish scents induce defensive behavior in live conspecifics. Additionally, we show for the first time in fish that these scents increase cortisol in conspecifics. To reach this conclusion, firstly, we exposed zebrafish to multi-sensorial cues (e.g., visual, tactile, chemical cues) from dead conspecifics that displayed defensive behaviors and increased cortisol. Also, when we limited zebrafish to chemical cues from dead conspecifics, similar responses arose. These responses coincide with the decaying destruction of epidermal cells, indicating that defensive and stress responses could take place as an effect of substances emanating from decaying flesh, as well as alarm substance released due to rupture of epidermal cells. Taken together, these results illustrate that living zebrafish utilize cues from dead conspecific to avoid or to cope with danger and ensure survival. © 2014 Elsevier Inc.

Farias R.L.S.,Federal University of Säo João del Rei | Farias R.L.S.,Federal University of Santa Maria | Gomes K.P.,Federal University of Säo João del Rei | Krein G.,São Paulo State University | Pinto M.B.,Federal University of Santa Catarina
Physical Review C - Nuclear Physics | Year: 2014

Although asymptotic freedom is an essential feature of QCD, it is absent in effective chiral quark models like the Nambu-Jona-Lasinio and linear sigma models. In this work we advocate that asymptotic freedom plays a key role in the recently observed discrepancies between results of lattice QCD simulations and quark models regarding the behavior of the pseudocritical temperature Tpc for chiral-symmetry restoration in the presence of a magnetic field B. We show that the lattice predictions that Tpc decreases with B can be reproduced within the Nambu-Jona-Lasinio model if the coupling constant G of the model decreases with B and the temperature. Without aiming at numerical precision, we support our claim by considering a simple ansatz for G that mimics the asymptotic-freedom behavior of the QCD coupling constant 1/αs∼ln(eB/ΛQCD2) for large values of B. © 2014 American Physical Society.

Bortoluzzi E.C.,University Of Passo Fundo | dos Santos D.R.,Federal University of Santa Maria | Santanna M.A.,Federal University of Santa Maria | Caner L.,CNRS Poitiers Institute of Chemistry: Materials and Natural Resources
Journal of Soils and Sediments | Year: 2013

Purpose: This study investigated desorption of potassium (K) and phosphorus (P) from soil and river suspended sediments sampled during a storm event in a Brazilian watershed traditionally used for tobacco plantations. Material and methods: Suspended sediment samples were collected automatically at the outlet of the watershed and were grouped into three phases: beginning (phase a), middle (phase b) and final stages (phase c) of the storm event. Granulometric and mineralogical characterisation of soils (0 to 0.20 m depth) and suspended sediments was determined, and K and P extractions were performed using a cation and anion exchange resin (CAER) membrane. A kinetic modelling approach was used to estimate the amount of K and P desorbed. Results and discussion: Clay-sized (<2 μm) content of the soils were all <21 %. Kaolinite, smectite (partially with hydroxy-Al interlayer) and a small amount of illite were found in the clay fraction of the different soils. The clay-sized fractions in sediments of phases a, b and c of the storm event were 49, 52 and 72 %, respectively. Smectite (>90 %) and kaolinite (<10 %) were the dominant clay minerals in the suspended sediments. The values of labile P and potentially available P of suspended sediments were higher than those for soils. In sediments, the highest values of labile P (325 mg kg-1) and labile K (4,458 mg kg-1) were found in phase c and in phase a, respectively. Conclusions: Particle size distribution and clay mineralogy of soils differed from those of suspended sediments collected during the storm event. By comparison with the watershed soils, suspended sediments collected during the storm event were enriched in fine particles composed mainly of smectite, and this may explain their P and K desorption behaviour. This suggests particle size and clay species selectivity processes during the transfer of sediment particles from soils to aquatic systems. The amounts of P and K desorbed from the suspended sediments in the three phases of the storm event were much larger than those desorbed from soils. This indicates that rainfall promoted the transfer of these nutrients to the watercourses. © 2013 Springer-Verlag Berlin Heidelberg.

Moresco R.N.,Ghent University | Moresco R.N.,Federal University of Santa Maria | Speeckaert M.M.,Ghent University | Delanghe J.R.,Ghent University
Autoimmunity Reviews | Year: 2015

IgA nephropathy (IgAN) is the most prevalent form of chronic glomerulonephritis in the world. The underlying pathogenesis of this autoimmune disease comprises the formation of immune complexes, including glycan-specific IgA1 or IgG antibodies and an aberrant glycosylation of IgA1. Until now, anatomopathological analysis of renal biopsies is essential for the diagnosis of IgAN and different histological classification systems have been proposed, e.g. the Oxford classification. However, a percutaneous renal biopsy is frequently not performed for several reasons and the Oxford classification system has some limitations. Since the poor prognosis of IgAN patients is partly the result of a delayed diagnosis, there is an urgent need for reliable noninvasive biomarkers that might be applicable in routine clinical practice. This article reviews the advances on the understanding of the underlying pathophysiological mechanisms of IgAN and discusses in depth the recent development of new biomarkers, including the use of proteomics and microRNAs. © 2015 Elsevier B.V.

Monks L.,URI Integrated Regional University Brazil | Tiggamann L.,URI Integrated Regional University Brazil | Mazuti M.A.,Federal University of Santa Maria | Oliveira V.J.,URI Integrated Regional University Brazil | Valduga E.,URI Integrated Regional University Brazil
Food and Bioprocess Technology | Year: 2012

The increasing demand for carotenoids by industries has drawn attention to their bio-production. Since pigments are intracellular, extraction steps are then needed after cell cultivation. In this work, different strategies for extraction of carotenoid pigments from Sporidiobolus salmonicolor (CBS 2636) were investigated. The cell rupture was carried out using dimethyl sulfoxide (DMSO), two pure compressed fluids, supercritical carbon dioxide and propane, and also a combination of pressurized fluid treatment followed by liquid DMSO. Dichloromethane, ethanol, ethyl acetate, and acetone were tested for the carotenoids extraction. Results obtained show that when multiple solvents were used a synergetic effect on the extent of carotenoids recovery was verified. Maximum concentration of total carotenoids (2,875 μg/L) was obtained in the treatment using supercritical CO 2 (300 bar/120 min) followed by dimethyl sulfoxide to disrupt the cell, and then the extraction with a solution of acetone/methanol (7:3, v/v). © 2011 Springer Science + Business Media, LLC.

Sabir S.M.,University Of Kashmir | Salman S.M.,Abdul Wali Khan University Mardan | Rocha J.B.T.,Federal University of Santa Maria
Environmental Toxicology and Pharmacology | Year: 2012

β-Seleno amines were screened for in vitro antioxidant activity. The compounds (C1-C4) were tested against lipid peroxidation induced by iron and sodium nitroprusside in rat brain and liver homogenates. The compounds showed inhibition against thiobarbituric acid reactive species (TBARS) induced by different pro-oxidants (10μM FeSO4and 5μM sodium nitroprusside (SNP) in rat brain and liver homogenates. The compounds exhibited strong antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and phosphomolybdenumassays. The IC50 values revealed that the β-seleno amines in which the amino groupwas protected with protecting groups tert-butyloxycarbonyl (Boc) and Tosyl (Ts) groups showed better antioxidant profiles compared to the free monoselenides. The total antioxidant activity of C1, C2, C3 and C4 were found to be 85.2±11.5, 114±7.9, 138±8.5, 125.81±5.2μM/ml of ascorbic acid respectively. Therefore, these compounds may be used as synthetic antioxidants. © 2012 Elsevier B.V. All rights reserved.

Martello A.R.,Federal University of Santa Maria | Hepp L.U.,URI Integrated Regional University Brazil | Kotzian C.B.,Federal University of Santa Maria
Revista de Biologia Tropical | Year: 2014

Additive partitioning of species diversity is a promising approach for analyzing patterns of diversity in mollusk communities, especially their spatial distribution. Our aims were to assess the distribution of mollusk communities in Southern Brazilian streams, and to evaluate the partitioning of community diversity at different spatial scales. The study was carried out in the lower course of the Toropi River, one of the main tributaries of the Ibicuí River Basin, in Southern Brazil. Four microbasins were considered: Sertão da Mata, Ribeirão, Tororaipi and Chiniquá, and sampling were undertaken in autumn, April and May 2009. Six sites were sampled in each stream: Two in 1st-order segments, two in 2nd-order segments, and two in 3rd-order segments. All species found and the community as a whole, exhibited a clumped distribution. However, the variance-to-mean ratios for the Drepanotrema kermatoides and Heleobia bertoniana were higher than those of other species, suggesting a higher degree of aggregation. The additive partitioning of the species richness showed that the observed richness at smallest scale (α=within streams) represented 20.7%, and among-streams (β1) represented 10.5% of the total richness. The richness and Shannon diversity index observed at the alpha scale, were higher than those observed at the first level of beta diversity scale (β1=among-streams). The interaction between passive dispersal, tolerance to changes in some environmental variables, abiotic factors, and clumped distribution might have determined the spatial distribution of the communities studied. The greatest variation at the larger scales of analysis, involving among-orders and among-microbasins (β2 and β3, respectively) components, was expected, considering that the increase in distance leads to greater differences in richness (higher beta diversity). In conclusion, our results showed that the clumped distribution influenced the partition of the diversity of the mollusk communities in the streams studied. Dispersal methods and tolerance to variations in abiotic factors also have important roles in determining high alpha diversity. The partitioning of diversity showed that to preserve limnetic mollusks, it is important to preserve local areas, i.e., streams. Accordingly, conservation of streams on a local scale will contribute to conservation of the entire basin and maintenance of regional diversity (gamma).

Abbas S.R.,University Of Kashmir | Sabir S.M.,University Of Kashmir | Ahmad S.D.,Jammu University | Boligon A.A.,Federal University of Santa Maria | Athayde M.L.,Federal University of Santa Maria
Food Chemistry | Year: 2014

The present study investigated the antioxidant and phenolic composition of sugarcane. The leaves and juices of thirteen varieties of sugarcane were studied for their antioxidant activity and protective effect on DNA damage. 2,2-Diphenyl-1-picrylhydrazyl radical (DPPH) assay was used to determine the radical scavenging activities in leaves and juices. Different varieties of sugarcane showed good antioxidant properties, IC50 values ranged from 20.82 to 27.47 μg/ml for leaves and from 63.95 to higher than 200 μg/ml for juice. The leaves and juice possess strong ability to protect against DNA damage induced by hydroxyl radical generated in Fenton reaction. The major phenolic acids, some flavonoid aglycone and glycosides were identified in leaves by high performance liquid chromatography. Ferulic acid (14.63 ± 0.03 mg/g), cumaric acid (11.65 ± 0.03 mg/g), quercetrin (10.96 ± 0.02 mg/g), caffeic acid (9.16 ± 0.01 mg/g) and ellagic acid (9.03 ± 0.02 mg/g) were prédominant in infusion of sugarcane. © 2013 Elsevier Ltd. All rights reserved.

Barcellos L.J.G.,University Of Passo Fundo | Marqueze A.,Unilassale Centro Universitario Lassalle | Trapp M.,Centro Universitario Feevale | Quevedo R.M.,University Of Passo Fundo | Ferreira D.,Federal University of Santa Maria
Aquaculture | Year: 2010

Both in nature and in aquaculture, fishes could experience periods of food deprivation or starvation. The hormonal regulation of metabolism in fishes is a complex process that involves several factors, including cortisol. Data about the effects of fasting on cortisol level were inconsistent, from no effect of starvation to a decrease or increase in cortisol level in fasted fish. Because of these highly variable results, it is not safe to speculate about the effects of fasting on cortisol levels in Rhamdia quelen. Thus, the present work aimed to elucidate the role of cortisol in controlling metabolism during fasting periods. Jundiás were distributed in five experimental groups. The first group was considered as the control and was fed normally. Jundiás of the second group were fasted for a 1-day period and then re-fed and those in the third group were fasted for 7 days and then re-fed. The fourth group was fasted for a 14-day period and then re-fed. The fifth batch was fasted for 21 days and then re-fed. Fasting periods of 7, 14, and 21 days significantly increased plasma cortisol levels compared with the control, with a return to basal level after 4 days of re-feeding. Blood glucose values remained unchanged during fasting with a low nonsignificant variation. At the end of the 7-, 14-, and 21-day fasting period, liver glycogen content was depleted, but 2 days after re-feeding, liver glycogen increased with values ranging from 1.1 to 3.5 times those of control concentrations. In contrast, no starvation effect was verified in the muscle glycogen. In conclusion, the variation in cortisol levels within treatment is suggestive of a functional role in control of intermediary metabolism during fasting in R. quelen. The early and large depletion of liver glycogen in fasted fish also suggests that this is a primary energy source in periods of food restriction. © 2010 Elsevier B.V. All rights reserved.

Zanella N.,University Of Passo Fundo | Cechin S.Z.,Federal University of Santa Maria
Zoologia | Year: 2010

The reproductive cycles of snakes can be influenced by many factors, both biotic and abiotic, and information about these factors can contribute significantly to knowledge of the biology of many species. Here, we present data on the reproductive biology (body size, sexual dimorphism and female reproductive cycle) of the forest-dwelling colubrid Echinanthera cyanopleura (Cope, 1885), based on analyses of 128 specimens preserved in collections and originating from the states of Paraná, Santa Catarina, and Rio Grande do Sul in southern Brazil. The snout-vent length of females was significantly greater than in males. The tail length of mature females was greater than in males, although this difference was not significant. Vitellogenesis occurs from August to December and eggs were found in greater frequency from October through December. Juveniles were found in larger numbers beginning in February, indicating that recruitment occurs from January to April. The reproductive cycle of this species is seasonal, which is usual for oviparous colubrids of temperate areas of Brazil. © 2010 Sociedade Brasileira de Zoologia.

Debien I.C.N.,University of Campinas | Rigo A.A.,URI Integrated Regional University Brazil | Mazutti M.A.,Federal University of Santa Maria | Oliveira J.V.,Federal University of Santa Catarina | Meireles M.A.A.,University of Campinas
Journal of Supercritical Fluids | Year: 2013

Biodegradable polymers have received increased attention due to their potential applications in the medicine and food industries; in particular, poly(L-lactic acid) (PLA) is of primary importance because of its biocompatibility and resorbable features. Recently, the synthesis of this biopolymer through the enzyme-catalyzed ring-opening polymerization of L-lactic acid in a compressed fluid has been considered promising. The aim of this work was to report the phase equilibrium data (cloud points) of the L-lactic acid + (propane + ethanol) and the L-lactic acid + (carbon dioxide + ethanol) systems. The phase equilibrium experiments were conducted in a variable-volume view cell employing the static synthetic method. These experiments were conducted in the temperature range of 323.15-353.15 K and at pressures up to 25 MPa; the mass ratio of ethanol to either CO2 or propane was maintained at 1:9. The L-lactic acid + (propane + ethanol) system exhibited vapor-liquid, liquid-liquid and vapor-liquid-liquid transitions, whereas the L-lactic acid + (carbon dioxide + ethanol) system only exhibited liquid-liquid type transitions. © 2013 Elsevier B.V. All rights reserved.

Benazzi T.,URI Integrated Regional University Brazil | Calgaroto S.,URI Integrated Regional University Brazil | Dalla Rosa C.,URI Integrated Regional University Brazil | Vladimir Oliveira J.,Federal University of Santa Catarina | Mazutti M.A.,Federal University of Santa Maria
Journal of Chemical Technology and Biotechnology | Year: 2013

This work evaluates the hydrolysis of sugarcane bagasse using supercritical carbon dioxide to obtain fermentable sugars in a single-step process. The effects of temperature, pressure, despressurization rate, moisture content and reaction time on the amount of fermentable sugars released were assessed. Results obtained showed the feasibility of adopting the present procedure since it produced about 287 g of fermentable sugars per kg of dry bagasse, which corresponds to 60% yield on the basis of total cellulose. Such a result is very attractive from an industrial viewpoint because there is no use of toxic solvent, solvent removal is completed (no residues), and the method has very low water consumption since the process is a solid-gas reaction. © 2012 Society of Chemical Industry.

Benazzi T.,URI Integrated Regional University Brazil | Calgaroto S.,URI Integrated Regional University Brazil | Astolfi V.,URI Integrated Regional University Brazil | Dalla Rosa C.,URI Integrated Regional University Brazil | And 2 more authors.
Enzyme and Microbial Technology | Year: 2013

This work evaluates the pretreatment of sugarcane bagasse combining supercritical carbon dioxide (SC-CO2) and ultrasound to enhance the enzymatic hydrolysis of pretreated bagasse. In a first step the influence of process variables on the SC-CO2 pretreatment to enhance the enzymatic hydrolysis was evaluated by mean of a Plackett-Burmann design. Then, the sequential treatment combining ultrasound+SC-CO2 was evaluated. Results show that treatment using SC-CO2 increased the amount of fermentable sugar obtained of about 280% compared with the non-treated bagasse, leading to a hydrolysis efficiency (based on the amount of cellulose) as high as 74.2%. Combining ultrasound+SC-CO2 treatment increased about 16% the amount of fermentable sugar obtained by enzymatic hydrolysis in comparison with the treatment using only ultrasound. From the results presented in this work it can be concluded that the combined ultrasound+SC-CO2 treatment is an efficient and promising alternative to carry out the pretreatment of lignocellulosic feedstock at relatively low temperatures without the use of hazardous solvents. © 2013 Elsevier Inc.

Caldart V.M.,Federal University of Santa Maria | Iop S.,Federal University of Santa Maria | Bertaso T.R.N.,URI Integrated Regional University Brazil | Cechin S.Z.,Federal University of Santa Maria
Zoological Studies | Year: 2012

The diet of the frog Crossodactylus schmidti was studied from Sept. 2009 to Mar. 2010 in the Turvo State Park, a locality of mesophytic semideciduous forest in southern Brazil, based on 93 stomach contents obtained by stomach-flushing (n = 80) and analysis of preserved specimens (n = 13). In addition to describing the diet, we determined the niche breadth on the basis of prey categories, and calculated electivities to evaluate the relation between the diet and prey availability in the environment. We also tested for differences in diets between sexes and between adults and juveniles. Crossodactylus schmidti consumed 19 categories of prey, of which ants, beetles, and dipterans had the highest importance values. Despite the varied diet, the niche breadth was narrow, with only a few prey categories being consumed predominantly. Ants, dipterans, and spiders were consumed in proportions similar to those estimated in the environment. There was no relationship between mouth width and length/volume of prey consumed, but there were significant sexual and age differences in the diet composition. Males consumed 18 prey categories, and females consumed 15; juveniles consumed 13 prey categories, and adults consumed 19. Despite differences in diet compositions between the sex and age groups, ants were the most important prey for all of them. Considering the varied diet and relationships between some of the most important items in the diet with their availability in the environment, C. schmidti can be characterized as an opportunistic feeder with feeding habits similar to those of other Crossodactylus species. Similarities in the importance of prey items such as ants, beetles, dipterans, and insect larvae in the diet of C. schmidti and other Hylodidae species are discussed.