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Background: This study aimed to verify the effects of bleaching toothpaste on colour stability, elastic properties, surface topography between aesthetic polyurethane and silicone elastomeric ligatures from different brands. Methods: Elastomeric ligatures tested were: 1‐Mini Single Case Ligature Stick (RMO‐polyurethane); 2‐Ligature "S" Shaped Dispenser (RMO‐Silicone); 3‐Sany‐tie (GAC‐translucent polyurethane); and 4‐Sili‐tie (GAC‐translucent silicone). The ligatures were randomly assigned from the brackets of canines and lower incisors of 40 patients. The study had two phases of 30 days in which a different toothpaste was used, followed by a washout period of 30 days. After each phase, ligatures were submitted to colour checking, tensile strength, and SEM. Results: The average of the ultimate tensile strength (m = 2.59; DP = 0.014) was higher in the control ligatures if compared to the tested ones (m = 2.24; DP = 0.014). There were no statistically significant differences between toothpastes regarding the type of ligature. Also, no interaction was observed between toothpastes in ligature's ultimate tensile strength and strain. The type of toothpaste did not minimize colour changes. Conclusion: In conclusion, there was no difference in colour stability and elastic properties between polyurethane or silicone aesthetic elastomeric modules. Whitening toothpastes had no impact on ligatures performance after 30 days in the oral cavity. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Biotecnología is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The population structure of the longsnout seahorse Hippocampus reidi (Ginsburg 1933) was evaluated in an estuarine system in northeastern Brazil. A total of 425 captures were performed in the Vaza-Barris estuary and 232 individuals were marked with Visible Implant Fluorescent Elastomers. The population was estimated to be composed of 428 fish. The von Bertalanffy growth curve shows a steeper growth during the first months of life, up to about 17 months, and stabilization after 16 cm and 27 months of age. The hereby study indicates that the Vaza-Barris estuary is home to resident populations of longsnout seahorses. Moreover, these populations use mangrove roots as the main substrate for attachment and present well-defined ecological characteristics, such as habitat fidelity and highly structured social organization. [ABSTRACT FROM AUTHOR]

Mortar panels painted with three different white acrylic coatings were exposed to the environment in urban (São Paulo) and rural (Pirassununga) sites in Brazil for 7 years. After this time, all panels were almost equally discoloured, and paint detachment was observed to only a small degree. The biofilms were composed mainly of cyanobacteria and filamentous fungi, principal genera being Gloeocapsa and Chroococcidiopsis of the cyanobacteria, and Cladosporium and Alternaria of the fungi. Two of the three paints in Pirassununga became covered by a pink film that contained red-encapsulated Gloeocapsa and clay particles. The third, an 800% elastomeric matt formulation, became discoloured with a grey, only slightly pink, film, although the same cyanobacteria were present. The levels of paint detachments from all films in both locations were low, with rating range of 0-1 of a maximum 5 (100% detachment). After high-pressure water jetting, paint detachments increased at both locations, up to 2 in Pirassununga and 3 in São Paulo. Discoloration decreased; L*A*B* analysis of surface discoloration showed that Δ E (alteration in colour from the original paint film) changed from 28-39 before cleaning to 13-16 afterwards. The pink coloration was not entirely removed from Pirassununga samples, suggesting that cyanobacterial cells are difficult to detach, and microscopic analysis of the biofilms confirmed that Gloeocapsa was still present as the principal contaminant on all surfaces, with Chroococcidiopsis being present as the second most common. Almost no fungi were detected after water jet application. [ABSTRACT FROM AUTHOR]

This experimental, comparative, laboratory study evaluated the effectiveness of the sterilization of single-use laparoscopic instruments - SULIs (grasper, dissector, scissors, Veress needle and electrosurgical probe system), after contamination-challenge with bacterial spores and sheep blood, and compared the results of the sterilization tests with those of the equivalent reusable instruments. The cleaning methods used were; ultrasonic washer with pulsatile water jet and enzymatic detergent, manual cleaning, cleaning with pressurized water and rinsing. The SULIs were sterilized with ethylene oxide and the reusable instruments in an autoclave. Sterility tests showed 100% negative results for recovery of contaminate microorganisms in both groups. It was concluded that, regarding the sterilization, that it is possible to reprocess SULIs. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Biociencias is the property of Revista Brasileira de Biociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this paper is to analyze the consequences of the current processes of formation of production chains and networks on the development of competencies at the firm level. The empirical study was performed on the Brazilian plastics transformation industry. The results indicate a very strong relationship exists between the competencies that are mastered by any given firm and its positioning in the various productive chains or networks. [ABSTRACT FROM PUBLISHER]

Statement of Problem: Maxillofacial elastomers undergo physical and mechanical degradation with disinfecting solutions. Solutions of Brazilian green propolis extract may be suitable alternatives for infection control of maxillofacial prostheses. However, their effects on the properties of the material are unknown., Purpose: The purpose of this in vitro study was to evaluate the effect of disinfection with solutions of Brazilian green propolis extract on the transmittance, translucency parameter, contrast ratio, and hardness of 2 maxillofacial elastomers (MDX4-4210 and MED-4014)., Material and Methods: Fifty disk-shaped specimens (3×10 mm) of each elastomer were randomly and equally divided into 4 groups of disinfectant agents and 1 control group: 3 separate groups of 11% green propolis extracts including aqueous (PAQ), glycolic (PGL), and alcoholic (PAL), a 2% chlorhexidine gluconate (CHX) group, and the control group of distilled water. Specimens were subjected to disinfection by immersion 3 times a week for 60 days. Color differences (ΔE values) were calculated with CIELab and CIEDE2000 formulas. Optical parameters and Shore A hardness were determined at 2 time points: at baseline and after the period of specimen disinfection. Data were analyzed by parametric and nonparametric analysis of variance and by multiple-comparison tests (α=.05)., Results: The ΔE values of specimens immersed in 11% PAL were not clinically acceptable for either elastomer. Regarding translucency parameter and contrast ratio, the immersion in 11% PAL and 11% PGL resulted in greater opacity and lower translucency of the material. Mean Shore A hardness values were not statistically significantly different at baseline or after 60 days of immersion in the solutions., Conclusions: The solution of Brazilian green propolis extract tested showed changes in optical parameters. Elastomers immersed in 11% alcoholic green propolis extract showed clinically unacceptable color and translucency changes. All hardness values of the tested elastomers were clinically acceptable after immersion in all tested disinfectant groups., (Copyright © 2019 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)