Alteration of blue pigment in artificial iris in ocular prosthesis: Effect of paint, drying method and artificial aging

The artificial iris is the structure responsible for the dissimulation and aesthetics of ocular prosthesis. The objective of the present study was to evaluate the color stability of artificial iris of microwaveable polymerized ocular prosthesis, as a function of paint type, drying method and accelerated aging. A total of 40 discs of microwaveable polymerized acrylic resin were fabricated, and divided according to the blue paint type ( n = 5): hydrosoluble acrylic, nitrocellulose automotive, hydrosoluble gouache and oil paints. Paints where dried either at natural or at infrared light bulb method. Each specimen was constituted of one disc in colorless acrylic resin and another colored with a basic sclera pigment. Painting was performed in one surface of one of the discs. The specimens were submitted to an artificial aging chamber under ultraviolet light, during 1008 h. A reflective spectrophotometer was used to evaluate color changes. Data were evaluated by 3-way repeated-measures ANOVA and the Tukey HSD test (alpha = 0.05). All paints suffered color alteration. The oil paint presented the highest color resistance to artificial aging regardless of drying method. (C) 2010 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Progression of experimental chronic peri-implantitis in dogs: Clinical and radiographic evaluation

Background: the aim of this study was to evaluate the progression of experimental peri-implantitis in dogs using implants with different surface coatings.Methods: Thirty-six dental implants with four different surface coatings, commercially pure titanium (cpTi), titanium plasma-sprayed (TPS), hydroxyapatite (HA), and acid-etched (AE), were placed in six mongrel dogs. Five months after implantation, peri-implantitis was induced by cotton ligatures to facilitate plaque accumulation for 60 days. After 60 days, the ligatures were removed and supragingival plaque control was initiated for 12 months. Probing depth (PD), clinical attachment level (CAL), vertical bone level (VBL), horizontal bone level (HBL), and mobility were obtained at baseline, and 20, 40, 60 (acute phase), and 425 days (chronic phase) after ligature removal.Results: PD and CAL changed around all implant surfaces after ligature placement (P < 0.0001). However, the means of PD and CAL were not statistically significant among the different surfaces (P > 0.05). The range of CAL variation, calculated between baseline and 60 days (acute phase) and between 60 and 425 days (chronic phase), decreased (P < 0.05). Bone loss increased during the entire experiment (P < 0.0001). The HA surface showed the greatest bone loss measurement (5.06 +/- 0.38 mm) and the TPS showed the smallest bone loss (4.27 +/- 0.62 mm). However, statistical significance was not assessed for different coatings (P > 0.05).Conclusions: the clinical data at the initial phase showed rapid and severe peri-implant tissue breakdown. However, removal of ligatures did not convert the acute destructive peri-implant phase to a non-aggressive lesion and the progression of peri-implantitis was observed at chronic phase. The,experimental peri-implantitis in dogs may be a useful model to evaluate the progression of peri-implantitis.

Purification and characterization of the exopolygalacturonase produced by Aspergillus giganteus in submerged cultures

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

Cassava wastewater as a substrate for the simultaneous production of rhamnolipids and polyhydroxyalkanoates by Pseudomonas aeruginosa

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

Decolorization of textile dye by Candida albicans isolated from industrial effluents

The aim of the present work was to observe microbial decolorization and biodegradation of the Direct Violet 51 azo dye by Candida albicans isolated from industrial effluents and study the metabolites formed after degradation. C. albicans was used in the removal of the dye in order to further biosorption and biodegradation at different pH values in aqueous solutions. A comparative study of biodegradation analysis was carried out using UV-vis and FTIR spectroscopy, which revealed significant changes in peak positions when compared to the dye spectrum. Theses changes in dye structure appeared after 72 h at pH 2.50; after 240 h at pH 4.50; and after 280 h at pH 6.50, indicating the different by-products formed during the biodegradation process. Hence, the yeast C. albicans was able to remove the color substance, demonstrating a potential enzymatic capacity to modify the chemical structure of pigments found in industrial effluents.

Using post-release monitoring data to optimize avian reintroduction programs: a 2-year case study from the Brazilian Atlantic Rainforest

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

How to not inflate population estimates? Spatial density distribution of white-lipped peccaries in a continuous Atlantic forest

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

Effect of Strength Training on Rate of Force Development in Older Women

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dynamical collapse in a degenerate binary fermion mixture using a hydrodynamic model

We use a time-dependent dynamical hydrodynamic model to study a collapse in a degenerate fermion-fermion mixture ( DFFM) of different atoms. Due to a strong Pauli-blocking repulsion among identical spin-polarized fermions at short distances, there cannot be a collapse for repulsive interspecies fermion fermion interaction. However, there can be a collapse for a sufficiently attractive interspecies fermion-fermion interaction in a DFFM of different atoms. Using a variational analysis and numerical solution of the hydrodynamic model, we study different aspects of collapse in such a DFFM initiated by a jump in the interspecies fermion-fermion interaction ( scattering length) to a large negative ( attractive) value using a Feshbach resonance. Suggestion for experiments of collapse in a DFFM of distinct atoms is made.

S-, P- and D-wave resonances in positronium-sodium and positronium-potassium scattering

Scattering of positronium (Ps) by sodium and potassium atoms has been investigated employing a three-Ps-state coupled-channel model with Ps(ls,2s,2p) states using a time-reversal-symmetric regularized electron-exchange model potential fitted to reproduce accurate theoretical results for PsNa and PsK binding energies. We find a narrow S-wave singlet resonance at 4.58 eV of width 0.002 eV in the Ps-Na system and at 4.77 eV of width 0.003 eV in the Ps-K system. Singlet P-wave resonances in both systems are found at 5.07 eV of width 0.3 eV. Singlet D-wave structures are found at 5.3 eV in both systems. We also report results for elastic and Ps-excitation cross sections for Ps scattering by Na and K.

Effective nonlinear Schrodinger equations for cigar-shaped and disc-shaped Fermi superfluids at unitarity

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

How may confinement affect technicolour?

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Parameter space for a dissipative Fermi-Ulam model

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

The late precambrian K-alkaline magmatism in the Ribeira Fold Belt: a case study of the Piracaia Pluton, State of São Paulo, SE Brazil, and its potential mineralization (Cu, Zn, Gd)

The Pluriserial Ribeira Magmatic System-590 of the Late Precambrian Ribeira Fold Belt comprises seven groups of high-K rocks of crustal or mantle origin with ages ranging between 620 and 570 Ma. One of these groups is represented by transalkaline suites akin to appinitic lamprophyres. The suites assemble one or more of following lithologies: (+/- quartz) gabbros and monzogabbros, (+/- quartz) diorites and monzodiorites, (+/- quartz) monzonites and syenites in addition to rare granites. All these rocks occur together in the Piracaia pluton, State of São Paulo. The mineralogy of the Piracaia suite comprises variable amounts of plagioclase (An 60-10), alkali-feldspars (orthoclase, microcline, albite), ortho- (Fe-hypersthene) and clinopyroxenes (augite), amphiboles (hornblende and rare late Fe-hastingsite), abundant biotite, quartz, opaques, sphene, allanite and zircon. Several magmatic pulses constructed the pluton. The Piracaia magma bulk trend evolved initially along the silica-undersaturation plane with simultaneous fractionation of accessory, mafic and felsic minerals. These are segregated in feldspar-rich cumulates. In the late stage, the evolutionary trend followed two distinct paths: one along the or-ab thermal barrier with the crystallization of syenites; the second one along the thermal valley in the or-ab-qz subsystem, producing quartz-syenites and granites. The source of the Piracaia magma was a 'vein-plus-wall-rock-system '. Together the pulses reflect increasing and decreasing participation of peridotites and mica pyroxenites, respectively, in the magmatogenic process. The magmatic pulses were stored in magma chambers, several drained by deep faults or fractures, which were successively reactivated and recharged. Each new pulse underwent mixing with earlier residual magma, followed by fractionation. During ascent through the hot and thickened post-collisional crust, the magma pulses underwent minor compositional changes by crustal contamination. The concentration of valuable elements (Cu, Zn, Gd) in the Piracaia pluton occurred during two phases of the magmatic evolution. Cu and Zn were enriched in cumulates and Gd was concentrated in residual quartz-syenitic veins. Due to their homogeneous dark colour and texture, the monzodiorites are exploited both for polished dimension stones and supports for sensitive scientific instruments. (C) 2001 Elsevier B.V. Ltd. All rights reserved.