Detection of Paracoccidioides spp. in environmental aerosol samples

Taking into account that paracoccidioidomycosis infection occurs by inhalation of the asexual conidia produced by Paracoccidioides spp. in its saprobic phase, this work presents the collection of aerosol samples as an option for environmental detection of this pathogen, by positioning a cyclonic air sampler at the entrance of armadillo burrows. Methods included direct culture, extinction technique culture and Nested PCR of the rRNA coding sequence, comprising the ITS1-5.8S-ITS2 region. In addition, we evaluated one armadillo (Dasypus novemcinctus) as a positive control for the studied area. Although the pathogen could not be isolated by the culturing strategies, the aerosol sampling associated with molecular detection through Nested PCR proved the best method for discovering Paracoccidioides spp. in the environment. Most of the ITS sequences obtained in this investigation proved to be highly similar with the homologous sequences of Paracoccidioides lutzii from the GenBank database, suggesting that this Paracoccidioides species may not be exclusive to mid-western Brazil as proposed so far. © 2013 ISHAM.

In situ evaluation of a low fluoride concentration gel with sodium trimetaphosphate in enamel remineralization

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Rheological behavior of binary aqueous solutions of poly(ethylene glycol) of 1500 g·mol-1 as affected by temperature and polymer concentration

The rheological behavior of poly(ethylene glycol) of 1500 g·mol -1(PEG1500) aqueous solutions with various polymer concentrations (w = 0.05, 0.10, 0.15, 0.20 and 0.25) was studied at different temperatures (T = 283.15, 288.15, 293.15, 298.15 and 303.15) K. The analyses were carried out considering shear rates ranging from (20 to 350) s-1, using a cone-and-plate rheometer under controlled stress and temperature. Classical rheological models (Newton, Bingham, Power Law, Casson, and Herschel-Bulkley) were tested. The Power Law model was shown suitable to mathematically represent the rheological behavior of these solutions. Well-adjusted empirical models were derived for consistency index variations in function of temperature (Arrhenius-type model; R2 > 0.96), polymer concentration (exponential model; R2 > 0.99) or the combination of both (R 2 > 0.99). Additionally, linear models were used to represent the variations of behavior index in the functions of temperature (R2 > 0.83) and concentration (R2 > 0.87). © 2013 American Chemical Society.

Photo-Fenton degradation kinetics of low ciprofloxacin concentration using different iron sources and pH

The aim of the present study was to compare the degradation kinetics of low (1 mg L-1) and high (25 mg L-1) concentrations of ciprofloxacin (CIP) aiming to decrease the concentration of additives and evaluate the pH limitation by the use of low iron concentrations and organic ligands. A parameterized kinetic model was satisfactorily fitted to the experimental data in order to study the performance of photo-Fenton process with specific iron sources (iron citrate, iron oxalate, iron nitrate) under different pH medium (2.5, 4.5, 6.5). The process modeling allowed selecting those process conditions (iron source, additives concentrations and pH medium) which maximize the two performance parameters related to the global equilibrium conversion and kinetic rate of the process. For the high CIP concentration, degradation was very influenced by the iron source, resulting in much lower efficiency with iron nitrate. At pH 4.5, highest TOC removal (0.87) was achieved in the presence of iron citrate, while similar CIP conversions were obtained with oxalate and citrate (0.98 after 10 min). For the low CIP concentration, much higher conversion was observed in the presence of citrate or oxalate in relation to iron nitrate up to pH 4.5. This behavior denotes the importance of complexation also at low dosages. Appropriate additives load (320 μM H 2O2; 6 μM Fe) resulted in a CIP conversion of 0.96 after10 min reaction with citrate up to pH 4.5. © 2013 Elsevier B.V. All rights reserved.

Effects of propiogenic ingredients on serum concentration of insulin and progesterone in non-lactating cows

Three experiments evaluated serum insulin and progesterone (P4) concentrations in grazing Gir×Holstein cows supplemented with monensin (MON) or propylene glycol (PPG; 2.5mL/kg of live weight0.75 per drench). Cows were non-lactating, ovariectomized, and received an intravaginal drug-releasing device containing 1.9g of P4 to estimate treatment effects on hepatic P4 degradation. In Exp. 1, 15 cows received, in a crossover design containing 2 periods of 21d, 0.1kg/d of corn in addition to 2g/d of kaolin (CON) or 0.2g/d of MON. Blood samples were collected on d 13 and 20 of each period. Cows receiving CON had greater (P<0.05) serum insulin concentrations compared with MON prior to and 6h after feeding. However, MON cows had greater (P=0.01) serum P4 concentrations compared with CON 18h after feeding. In experiment 2, 15 cows received, in a replicated crossover design containing 2 periods of 24h, a single drench of PPG or water (WT). Cows receiving PPG had greater (P<0.01) serum insulin concentrations compared with WT from 0.5 to 3h after drench. However, PPG cows had reduced (P<0.05) serum P4 concentrations compared with WT at 1 and 2h after drench. In experiment 3, 13 cows received, in a replicated 3×3 Latin square design containing 3 periods of 24h, 3 PPG drenches administered 1h apart (PPG3x), 3 WT drenches administered 1h apart, or 1 PPG drench+2 WT drenches administered 1h apart (PPG1x). Serum insulin concentrations increased proportionally to PPG dosage (treatment×hour; P<0.01). However, mean serum P4 concentration was greater (P<0.01) in WT cows compared with PPG1x and PPG3x, but similar (P=0.25) between PPG1x and PPG3x cows. In conclusion, feeding propiogenic ingredients to grazing cows failed to substantially increase serum P4 concentrations. © 2013 Elsevier B.V.

Elevated atmospheric CO2 concentration increases rice blast severity

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of ethanol, acidity and chloride concentration on the corrosion resistance of AISI 316L stainless steel

The influence of ethanol, sulfuric acid and chloride on the corrosion resistance of 316L stainless steel was investigated by means of polarization curves and electrochemical impedance spectroscopy measurements. Over the studied range, the steel corrosion potential was independent of H2SO 4 and NaCl concentrations in aqueous solution. On the other hand, in solution containing 65 wt.% ethanol and 35 wt.% water, the corrosion potentials were higher than those obtained in aqueous solution. Besides, the steel corrosion potential was affected by the addition of H2SO4 and NaCl in solution. In solutions with and without ethanol, plus 0.35 wt.% NaCl, the presence of 1 wt.% H2SO4 inhibited the appearance of pitting corrosion. © 2013 Sociedade Brasileira de Química.

Influence of the indium concentration on microstructural and electrical properties of proton conducting NiO-BaCe0.9-xIn xY0.1O3-δ cermet anodes for IT-SOFC application

Optimization of the major properties of anodes based on proton conductors, such as microstructure, conductivity and chemical stability, is yet to be achieved. In this study we investigated the influence of indium on the chemical stability, microstructural and electrical characteristics of proton conducting NiO-BaCe0.9-xInxY0.1O 3-δ (NiO-BCIYx) anodes. Four compositions of cermet anode substrates NiO-BCIYx were prepared using the method of evaporation and decomposition of solutions and suspensions (EDSS). Sintered anode substrates were reduced and their microstructural and electrical properties were examined before and after reduction as a function of the amount of indium. Anode substrates tested on chemical stability in the CO2 atmosphere showed high stability compared to anode substrates based on commonly used doped barium cerates. Microstructural properties of the anode pellets before and after testing in CO2 were investigated using X-ray diffraction analysis. Impedance spectroscopy measurements were used for evaluation of electrical properties of the anode pellets and the conductivity values of reduced anodes of more than 14 S cm-1 at 600 °C confirmed percolations through Ni particles. Under fuel cell operating conditions, the cell with a Ni-BCIY20 anode achieved the highest performance, demonstrating a peak power density 223 mW/cm2 at 700 °C confirming the functionality of Ni-BCIY anodes.© 2013 Elsevier B.V. All rights reserved.

Maternal flow-mediated dilation and nitrite concentration during third trimester of pregnancy and postpartum period

Objectives. To compare maternal flow-mediated dilation (FMD) of the brachial artery and nitrite concentration between third trimester of pregnancy (3rdT) and postpartum (PP) period. Additionally, we will evaluate whether FMD correlates with nitrite concentration in both periods. Methods. Eligibility criteria was healthy women with singleton pregnancy, gestational age >28 weeks, nonsmokers, and no personal or family history of vascular disease. Each women was examined during 3rdT and between 8 and 12 weeks PP to evaluate FMD and nitrite concentration in whole blood. Women not examined in both periods were excluded. Values between both periods were compared using paired t tests. Correlation between FMD and nitrite was examined by Pearson correlation coefficient. Significance level set as p<0.05. Results. We invited 42 pregnant women. Among them, 35 were eligible and 7 of them were excluded for not attending the PP evaluation resulting in 28 participants analyzed. We found no significant change in FMD (10.39±5.57% vs. 8.42±4.21%; p=0.11; 3rdT vs. PP, respectively) and no significant change in nitrite concentration (257.41±122.95nmol/L vs. 237.16±90.01nmol/L; p=0.28). Baseline brachial artery diameter had a significant reduction (3.11±0.30 to 2.75±0.34mm; p<0.01). No significant correlation between FMD and nitrite during 3rdT (r=-0.13; p=0.50) or PP (r=0.14; p=0.48) was found. Conclusions. We did not observe significant changes in both FMD and nitrite concentration between third trimester and the PP period. FMD did not correlate with nitrite in both periods. More studies are needed to confirm our findings. © Informa Healthcare USA, Inc.

Influence of the concentration of polyols on the rheological and spectral characteristics of guar gum

Polyols are widely used as sugar substitutes and provide texture to foods. Guar gum has many applications in food industry such as increasing product viscosity and improving texture. Knowledge of rheological properties of gum/polyol systems is important to permit replacing sugar while maintaining product texture. In this work, rheological properties of 0.1, 0.5 and 1 g/100 g guar solutions containing 10 and 40 g/100 g of maltitol, sorbitol, or xylitol were studied. The behavior of these mixtures was evaluated by steady and oscillatory shear measurements, and after a freezing/thawing cycle. Apparent viscosity of guar solutions increased with addition of polyols and with the increase in their concentrations, except for 40 g/100 g sorbitol addition to 1 g/100 g guar gum, in which the apparent viscosity decreased. Addition of polyols also increased the dynamic moduli of the systems. In mixtures of guar with 40 g/100 g polyol, the phase angle (δ) was below unity, but was dependent on frequency, which is characteristic of concentrated solutions with a certain degree of structuring. FTIR spectroscopy was studied to provide information on possible interactions between guar gum and polyols. Analyses carried out after freezing/thawing showed no changes in the viscoelastic behavior of the solutions. © 2013 Elsevier Ltd.

The systematic significance of floral morphology, nectaries, and nectar concentration in epiphytic cacti of tribes Hylocereeae and Rhipsalideae (Cactaceae)

A long-standing interest in cactus taxonomy has existed since the Linnaean generation, but an appreciation of the reproductive biology of cacti started early in the 1900s. Numerous studies indicate that plant reproductive traits provide valuable systematic information. Despite the extensive reproductive versatility and specializations in breeding systems coupled with the striking floral shapes, the reproductive biology of the Cactaceae has been investigated in approximately 10% of its species. Hence, the systematic value of architectural design and organization of internal floral parts has remained virtually unexplored in the family. This study represents the most extensive survey of flower and nectary morphology in the Cactaceae focusing on tribes Hylocereeae and Rhipsalideae (subfamily Cactoideae). Our objectives were (1) to conduct comparative morphological analyses of flowers and floral nectaries and (2) to compare nectar solute concentration in these two tribes consisting of holo- and semi-epiphytic species. Flower morphology, nectary types, and sugar concentration of nectar have strong taxonomic implications at the tribal, generic and specific levels. Foremost, three types of nectaries were found, namely chamber nectary (with the open and diffuse subtypes), furrow nectary (including the holder nectary subtype), and annular nectary. All Hylocereeae species possess chamber nectaries, in which the nectarial tissue has both trichomes and stomata. The Rhipsalideae are distinguished by two kinds of floral nectaries: furrow and annular, both nectary types with stomata only. The annular nectary type characterizes the genus Rhipsalis. Nectar concentration is another significant taxonomic indicator separating the Hylocereeae and Rhipsalideae and establishing trends linked to nectar sugar concentration and amount of nectar production in relation to flower size. There is an inverse relationship between flower size and amount of nectar production in the smaller Rhipsalideae flowers, in which nectar concentration is more than two-fold higher despite the smaller volume of nectar produced when compared to the large Hylocereeae flowers. Variability of nectary morphology and nectar concentration was also evaluated as potential synapomorphic characters in recent phylogenies of these tribes. In conclusion, our data provide strong evidence of the systematic value of floral nectaries and nectar sugar concentration in the Cactaceae, particularly at different taxonomic levels in the Hylocereeae and Rhipsalideae. © 2013 Perspectives in Plant Ecology, Evolution and Systematics.

Influence of ethanol and glycerol concentration over functional and structural properties of zein-oleic acid films

This study was performed in order to determine the effect of the addition of different concentrations of glycerol and ethanol over functional and structural properties of zein-oleic acid films. Films were prepared from zein and oleic acid formulations, containing: 0, 10, 20 and 30% (w/w) of glycerol as plasticizer and 75, 80, 85, 90 and 95% (v/v) of ethanol as zein solvent. Water vapor permeability (WVP) at 4 and 24 C, opacity, water solubility and structural behavior of the film were assessed. The film water barrier properties, WVP and water solubility, were increased when higher ethanol concentration and lower glycerol concentration were used. Furthermore, WVP at 4 C was lower than WVP at 24 C due to the crystalline solid state of oleic acid at lower temperatures. Likewise, opacity, homogeneity and structure of the composite film were improved as ethanol increased and glycerol lowered. © 2013 Elsevier B.V. All rights reserved.

Atributos da validação do método analítico para quantificação da biotina empregando a técnica potenciométrica

Pós-graduação em Alimentos e Nutrição - FCFAR

Carbono orgânico solúvel em água no material particulado de regiões canavieiras do Estado de São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação de sistemas para a aplicação de inseticidas para controle de Aedes aegypti (l.) (Diptera: Culicidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)