Search results for "GLASS"
showing 10 items of 1153 documents
Effect of various dentin disinfection protocols on the bond strength of resin modified glass ionomer restorative material.
2017
Background Disinfection of dentin surface prior to any restorative therapy is important for the longevity of the treatment rendered. However, these dentin disinfection methods should itself not interfere with the adhesion of the restorative material. Therefore the aim of this study was to determine the effect of various dentin disinfection protocols on the shear bond strength (SBS) of resin modified glass ionomer cement (RMGIC). Material and methods The occlusal surface of 40 extracted premolars were trimmed to obtain a flat dentinal surface and was randomly divided into four groups. CTRL was the control group; NaOCl was 1% sodium hypochlorite disinfection group; CHX was 2% chlorhexidine di…
Electrochemical identification of toxigenic fungal species using solid-state voltammetry strategies.
2018
An electrochemical methodology for the characterization of mycotoxin-producing fungal species from the genera Aspergillus and Fusarium using solid-state voltammetry is described. Upon attachment of fungal colony microsamples to glassy carbon electrodes in contact with aqueous acetate buffer, characteristic voltammetric signals mainly associated to the oxidation of polyphenolic metabolites are recorded. The possibility of fungi-localized electrochemical processes was assessed by means of electron microscopy and field emission scanning electrochemical microscopy coupled to the application of oxidative potential inputs. Using pattern recognition methods, the determined voltammetric profiles we…
What is the influence of parents' myopia on their children's myopic progression? A 22-year follow-up study.
2016
Purpose To study the connection between parental myopia and their children's myopia from school age to adulthood. Methods Two hundred and forty myopic schoolchildren (119 boys, 121 girls, mean age 10.9 years) with no previous spectacles for myopia were recruited to a 3-year treatment trial with different use of spectacles. Follow-ups were performed at mean ages of 13.9, 23.7 and 33.2 years for 238, 176 and 170 subjects respectively. Subjective refraction was calibrated to the spherical equivalent at corneal level (SEcor). Corneal refractive power (CR) and axial length (AL) were measured. Parental myopia was assessed with a questionnaire and the children assigned accordingly to one of three …
Antibacterial potency and fluoride release of a glass ionomer restorative material containing different concentrations of natural and chemical produc…
2018
Background This study investigated the antibacterial efficacy against Streptococcus mutans and fluoride release of a conventional glass ionomer (GI) contained natural and chemical agents. Material and methods Two hundred and ten GI specimens were divided into ten groups (n=21) according to the concentrations of the additives as; Propolis extract containing GI (Groups 1, 2, 3) with concentrations of 0.25%, 0.75% and 1.25% respectively, Miswak extract containing GI (Groups 4, 5, 6) and Chlorhexidine containing GI (Groups 7, 8, 9) with the same concentrations. The prepared specimens were subjected to antimicrobial activity by well diffusion, bacterial adherence, and fluoride release (from 2 to…
Non-conventional Ce:YAG nanostructures via urea complexes
2019
AbstractCe:YAG nanostructures (Ce:YAG = Cerium in Yttrium Aluminium Garnet), easy to control and shape, have been prepared via templating approach using natural and synthetic materials (i.e. paper, cotton wool and glass wool) previously soaked with a gel-like metals precursor and then thermally treated to achieve the wished morphology. The final material, otherwise difficult to process, can be easily moulded, it is lightweight, portable and forms, at the nanoscale, homogeneous layers of interconnected but not agglomerated nanoparticles (15 ± 5 nm). Using the same synthetic route, called Urea-Glass-Route, but in absence of a template, extremely pure Ce:YAG nanoparticle (45 ± 5 nm) can be als…
Retrieving infinite numbers of patterns in a spin-glass model of immune networks
2013
The similarity between neural and immune networks has been known for decades, but so far we did not understand the mechanism that allows the immune system, unlike associative neural networks, to recall and execute a large number of memorized defense strategies {\em in parallel}. The explanation turns out to lie in the network topology. Neurons interact typically with a large number of other neurons, whereas interactions among lymphocytes in immune networks are very specific, and described by graphs with finite connectivity. In this paper we use replica techniques to solve a statistical mechanical immune network model with `coordinator branches' (T-cells) and `effector branches' (B-cells), a…
In vitro quantitative comparison of erosive potential of infant mouthwashes on glass ionomer cement
2018
Background The widespread use of mouthwashes, specially in children, is a concern, since the long-term use may modify the topography of dental materials. However, this process still unclear regarding the wear related to infant mouthwashes on glass ionomer cement. Thus, the purpose of this investigation was evaluate the erosive potential of infant mouthwashes on glass ionomer cement specimens. Material and methods Forty round-shaped specimens were divided into 4 groups (N=10) and submitted to erosive cycling for 15 days, being exposed 2X/day in the following children's active agents mouthwash solutions: G1- cetylpyridinium chloride, G2- xylitol and triclosan and G3 - Malva sylvestris and xyl…
Solving a large cutting problem in the glass manufacturing industry
2020
Abstract The glass cutting problem proposed by Saint Gobain for the 2018 ROADEF challenge includes some specific constraints that prevent the direct application of procedures developed for the standard cutting problem. On the one hand, the sheets to be cut have defects that make them unique and they must be used in a given order. On the other hand, pieces are grouped in stacks and the pieces in each stack must be cut in order. There are also some additional characteristics due to the technology being used, especially the requirement for a three-stage guillotine cutting process. Taking into account the sequencing constraints on sheets and pieces, we have developed a beam search algorithm, us…
Comparison of the shear bond strength of 3D printed temporary bridges materials, on different types of resin cements and surface treatment
2019
Background Thus, purpose of this study was to compare the shear bond strength of the resin cement and the resin modified glass ionomer cement on 3D printed temporary material for crowns and bridges in combination with different surface treatment modalities. Material and methods Test specimens VarseoSmile Temp material (Bego, Bremen, Germany) (n=64) in the form of rectangular blocks (n=32) and cylindrical test specimens (n=32) were printed using the Varseo S 3D printer (Bego, Bremen, Germany). The specimens were divided into 4 groups, with 8 specimens of each kind. Two groups (n=16 pairs) were blasted with Perlablast® Micro [PM] 50µm (Bego, Bremen, Germany) and two groups (n=16 pairs) were b…
Characterizing the initial conditions of heavy-ion collisions at the LHC with mean transverse momentum and anisotropic flow correlations
2022
Physics letters / B 834, 137393 (2022). doi:10.1016/j.physletb.2022.137393