Energy deficit does not affect immune responses of experimentally infected pacu (Piaractus mesopotamicus)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Rietveld refinement, cluster modelling, growth mechanism and photoluminescence properties of CaWO4: Eu3+ microcrystals

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

Rietveld refinement and optical properties of SrWO4:Eu3+ powders prepared by the non-hydrolytic sol-gel method

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Structure, Morphology, and Optical Properties of (Cal(1-3x)Eu(2x)) WO4 Microcrystals

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

Fabrication and structural characterization of bismuth niobate thin films grown by chemical solution deposition

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Titanium K-edge XAS study on local structure of Pb1-xCaxTiO3 ferroelectric ceramics

In order to characterize the local structure of Pb1-xCaxTiO3 (PCT) samples, Ti K-edge XANES measurements were performed and showed that Ca incorporation to PbTiO3 structure leads to a decreasing of local distortion of Ti atoms in relation to oxygen atoms at the TiO6 octahedra. Moreover, according to EXAFS measurements, the local structure around Ti atoms exhibits tetragonal symmetry with P4mm space group for samples with x <= 0.475, whereas orthorhombic symmetry with Pbnm space group was observed for x equals to 0.50 and 0.55.

Disease resistance of pacu Piaractus mesopotamicus (Holmberg, 1887) fed with beta-glucan

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Physical properties of self-polarized PZT thin films at compositions around the morphotropic phase boundary

The physical properties of self-polarized PbZr1-xTixO3 thin films with no preferential orientation in a range of compositions 0.46 <= x <= 0.50 were investigated. Structural analysis revealed the coexistence of monoclinic-tetragonal and monoclinic-rhombohedral phases at compositions 0.46 <= x <= 0.49, where the monoclinic phase was in the majority and both the tetragonal and the rhombohedral phases in the minority. The dielectric permittivity (epsilon'= 447) reached its maximum at around composition x = 0.48. Asymmetries in the macroscopic and local hysteresis loops confirmed the existence of the self-polarization effect in the studied films.

The immune system is limited by oxidative stress: dietary selenium promotes optimal antioxidative status and greatest immune defense in pacu Piaractus mesopotamicus

Reactive oxygen species (ROS) are reactive molecules containing oxygen, that form as byproducts of aerobic metabolism, including immune system processes. Too much ROS may cause oxidative stress. In this study, we examined whether it can also limit the production of immune system compounds. To assess the relationship between antioxidant status and immunity we evaluated the effect of dietary supplementation with organic selenium, given at various levels for 10 days, on the antioxidant and immune system of the pacu fish (Piaractus mesopotamicus). Fish fed a diet containing 0.6 mg Se-yeast kg(-1) showed significant improvement in antioxidant status, as well as in hematological and immunological profiles. Specifically, they had the highest counts for catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), red blood cells, and thrombocytes; the highest leukocyte count (particularly for monocytes); and the highest serum lysozyme activity. There was also a positive correlation between GPx and lysozyme in this group of fish. These findings indicate that short-term supplementation with 0.6 mg Se-yeast kg(-1) reestablished the antioxidative status, allowing the production of innate components which can boost immunity without the risk of oxidative stress. This study shows a relationship between oxidative stress and immunity, and, from a practical perspective, shows that improving immunity and health in pacu through the administration of selenium could improve their growth performance.

Uncaria tomentosa increases growth and immune activity in Oreochromis niloticus challenged with Streptococcus agalactiae

Cat's claw (Uncaria tomentosa) is an Amazon herb using in native cultures in Peru. In mammals, it has been described several effects of this herb. However, this is the first report of its use on the diet of fish. The aim of this study was to determinate the effect of this plant on the growth and immune activity in Oreochromis niloticus. Nile tilapia (81.3 ± 4.5 g) were distributed into 5 groups and supplemented with 0 (non-supplement fish), 75, 150, 300, and 450 mg of U. tomentosa.kg(-1) of diet for a period of 28 days. Fish were inoculated in the swim bladder with inactivated Streptococcus agalactiae and samples were taken at 6, 24, and 48 h post inoculation (HPI). Dose dependent increases were noted in some of the evaluated times of thrombocytes and white blood cells counts (WBC) in blood and exudate, burst respiratory activity, lysozyme activity, melanomacrophage centers count (MMCs), villi length, IgM by immunohistochemistry in splenic tissue, and unexpectedly on growth parameters. However, dietary supplementation of this herb did not affect red blood cells count (RBC), hemoglobin, and there were no observed histological lesions in gills, intestine, spleen, and liver. The current results demonstrate for the first time that U. tomentosa can stimulate fish immunity and improve growth performance in Nile tilapia.

Structure of copper complexes adsorbed on a silica gel surface chemically modified with benzimidazole

Silica gel having a particle size between 0.2 and 0.05 mm and a specific surface area, S BET = 473 m 2 g -1, was chemically modified with benzimidazole. Adsorption isotherms of CuX 2 (X = Cl, Br or ClO 4) from ethanol and acetone solutions were studied at 298 K. The metal is bonded to the surface through the free nitrogen atom of the attached benzimidazole. The average number of ligands co-ordinated to the central metal ion was shown to depend on the solid surface loading by the solute. At low loading the electronic and ESR spectral parameters indicated that the copper ion is in a distorted-tetragonal symmetry field.

Eficácia do levamisol como imunoestimulante, redutor de estresse e antiparasitário no pacu

Pós-graduação em Aquicultura - FCAV

Efeito da infiltração de sílica pelo método sol-gel na resistência à flexão de bicamadas de porcelana e Y-TZP

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Bond strength and Raman analysis of the zirconia-feldspathic porcelain interface

The test groups were experimental zirconia, Zirkonzahn zirconia, and Schuetz zirconia. Blocks of partially sintered zirconia were cut into disks (n=20) and then veneered with a feldspathic porcelain. Half of the specimens from each group (n=10) were incubated in 37°C water for 24 hours, and the other half were thermocycled. All the specimens were then subjected to shear testing. The fractured areas were analyzed with optical stereomicroscopy and classified as adhesive, cohesive, or an adhesive-cohesive failure. Spectral patterns were examined to detect bands related to the zirconia and feldspathic porcelain phases. The shear strength data were submitted to 2-way ANOVA. Results No significant differences in shear bond strength were observed among the 3 groups, regardless of whether or not the specimens were thermocycled. Adhesive failures were the most prevalent types of failure (70%). Raman spectra were clearly distinguished for all the materials, which showed the presence of tetragonal and monoclinic phases. Conclusions The controlled production of the experimental zirconia did not influence the results of the bond strength. Raman analysis suggested a process of interdiffusion by the presence of peaks associated with the zirconia and feldspathic ceramics.

Influência de carboidratos na homeostase fisiológica e imunológica de juvenis de surubins (Pseudoplatystoma sp.)

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