Effect of different disinfectants on the microhardness and roughness of acrylic resins for ocular prosthesis

Background: Ocular prosthesis materials should have specific properties for their indication and durability; therefore, it is important to investigate their physical behaviour when affected by several disinfectants. Objectives: This study evaluated the influence of different disinfecting solutions on the microhardness and surface roughness of acrylic resins for ocular prosthesis. Materials and Methods: Fifty samples simulating ocular prostheses were fabricated with N1 resin and colourless resin and divided (n = 10) according to the disinfectant used: neutral soap, Opti-free, Efferdent, 1% hypochlorite (HYC) and 4% chlorhexidine (CHX). Samples were stored in saline solution at 37°C and disinfected during 120 days. Both microhardness and roughness were investigated before, after 60 days and 120 days of disinfection and storage. Microhardness was measured using a microhardner and the roughness with a roughness device. Results: N1 resin showed lower microhardness when compared with colourless resin (p < 0.05). HYC and CHX groups exhibited the highest change of microhardness and roughness values (p < 0.05). An increase in roughness and reduction in microhardness of ocular acrylic resins were observed after both periods of disinfection and storage (p < 0.05). Conclusion: Both disinfection/storage periods affected the microhardness and roughness values of the samples. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

Functional extinction of birds drives rapid evolutionary changes in seed size

Local extinctions have cascading effects on ecosystem functions, yet little is known about the potential for the rapid evolutionary change of species in human-modified scenarios. We show that the functional extinction of large-gape seed dispersers in the Brazilian Atlantic forest is associated with the consistent reduction of the seed size of a keystone palm species. Among 22 palm populations, areas deprived of large avian frugivores for several decades present smaller seeds than nondefaunated forests, with negative consequences for palm regeneration. Coalescence and phenotypic selection models indicate that seed size reduction most likely occurred within the past 100 years, associated with human-driven fragmentation. The fast-paced defaunation of large vertebrates is most likely causing unprecedented changes in the evolutionary trajectories and community composition of tropical forests.

A dramatização da crise dos valores sociais e humanos em Tess of the d'Urbervilles, de Thomas Hardy

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A re-configuração das atribuições do diretor escolar com a instauração do regime de gestão democrática da escola

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Os modos contemporâneos de gestão do espaço urbano e a invenção de si

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The management of cover plant residues for cotton cropped in a no-tillage system

The cutting of plant residue in no-tillage systems under certain environmental conditions becomes necessary to adequately establish and grow crops. This study aims to assess the effect on the yield of different methods of managing millet plant residue in cotton plantations. The study was conducted during the agricultural years 2006/07 and 2007/08, and the treatments included no-mechanical-treatment tillage and the use of a rotary shredder, crimper-roller, and mechanical disintegrator for millet plants before sowing the cotton. Evaluations were performed for the residue fragmentation, emergence speed, percent of soil cover during the cycle and yield of the cotton crop. The emergence speed was faster in the management with the rotary shredder. In 2006/07, the no-tillage treatment showed a rate of loss for soil cover that was 46 percent greater than the disintegrator treatment. The rotary shredder and the disintegrator yielded greater soil coverage during the cultivation cycle, and the yield was highly correlated with the soil cover at 75 days after emergence. The management of the millet residue affected the cotton plants for the two-year study period.

Effect of calcium on the structural properties of Ba(1-x)Ca (x) TiO3 particles synthesized by complex polymerization method

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of intrinsic nanoparticle pigmentation on the color stability of denture base acrylic resins

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

Bleaching effectiveness, hydrogen peroxide diffusion, and cytotoxicity of a chemically activated bleaching gel

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

Measuring the Spin of Black Holes in Binary Systems Using Gravitational Waves

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

Cross-cultural adaptation of Preschool Language Assessment Instrument: Second Edition

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

Effect of Fe-doping on the structural, microstructural, optical, and ferroeletric properties of Pb1/2Sr1/2Ti1-xFexO3 oxide prepared by spin coating technique

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

In vitro study of color stability of polycrystalline and monocrystalline ceramic brackets

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Improvement of gamete quality and its short-term storage: an approach for biotechnology in laboratory fish

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

Structural damage detection in an aeronautical panel using analysis of variance

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