Background: Color stability of glass ionomers (GIs) could be affected by many factors such as pH and consumption of liquid medications like antibiotics. Most common antibiotics used during childhood are amoxicillin suspension (AM.S) and azithromycin suspension (AZ.S) which have acidic and basic pH respectively. Aim: to evaluate and compare the effect of AM.S and AZ.S on color stability of nano resin-modified GI. Methods: Thirty disc of nano resin-modified glass ionomer (2mm height x 4mm diameter) were divided into three groups (n=10 for each) and independently exposed to AM.S, AZ.S, and artificial saliva (A.S.). Color stability was evaluated in triplicate by VITA Easyshade® before and after three immersion protocols, repeated over a three-week duration with two-days intervals. In each protocol, samples were exposed for two minutes, three times daily for AM.S, once daily for AZ.S, and A.S. full day. GI discs rinsed off after each immersion and kept in artificial saliva until next immersion period. Results: One way ANOVA test and Post-hoc analysis of the changes in color space compartments of nano-resin modified GI samples demonstrated just a significant change (p˂0.05) in yellow-blue axis (Δb*) value after immersion in AM.S in comparison with A.S. Total Color change values (ΔE) of nano resin-modified glass ionomer samples also illustrated a significant effect (p˂0.05) between AM.S and A.S. only. The highest (ΔE) value was recorded for samples immersed in AM.S (ΔE =12.5) followed by AZ.S (ΔE=6.5) while the lowest was recorded for A.S. (ΔE=1.1). Conclusion: AM.S (the acidic medication) exhibited a higher staining effect to nano-resin modified GI samples when compared with AZ.S (the basic medication). Several factors such as low pH, more exposure time and coloring material of the immersion media added critical roles in coloring instability.
In this paper, some estimators of the unknown shape parameter and reliability function of Basic Gompertz distribution (BGD) have been obtained, such as MLE, UMVUE, and MINMSE, in addition to estimating Bayesian estimators under Scale invariant squared error loss function assuming informative prior represented by Gamma distribution and non-informative prior by using Jefferys prior. Using Monte Carlo simulation method, these estimators of the shape parameter and R(t), have been compared based on mean squared errors and integrated mean squared, respectively
This research aims to investigate the color distribution of a huge sample of 613654 galaxies from the Sloan Digital Sky Survey (SDSS). Those galaxies are at a redshift of 0.001 - 0.5 and have magnitudes of g = 17 - 20. Five subsamples of galaxies at redshifts of (0.001 - 0.1), (0.1 - 0.2), (0.2 - 0.3), (0.3 - 0.4) and (0.4 - 0.5) have been extracted from the main sample. The color distributions (u-g), (g-r) and (u-r) have been produced and analysed using a Matlab code for the main sample as well as all five subsamples. Then a bimodal Gaussian fit to color distributions of data that have been carried out using minimum chi-square in Microsoft Office Excel. The results showed that the color distributions of the main sample and
... Show MoreFabric design is one of the arts in which humans participate functionally and aesthetically. Researching its design aspects is an important goal, especially after taking technical developments to cover many of its fields. Modern designs emphasize the importance of preparing designs and implementing them according to the child’s ability, inclinations and desires (mental, psychological and emotional). ), as the child is the real focus of the design idea, and the designer has paid most of his attention to the requirements and needs of this stage (childhood stage) because of its importance in the life of society, as he focused his attention on implementing designs that could achieve stability and stability in the child’s psyche through s
... Show MoreIn this paper, a compression system with high synthetic architect is introduced, it is based on wavelet transform, polynomial representation and quadtree coding. The bio-orthogonal (tap 9/7) wavelet transform is used to decompose the image signal, and 2D polynomial representation is utilized to prune the existing high scale variation of image signal. Quantization with quadtree coding are followed by shift coding are applied to compress the detail band and the residue part of approximation subband. The test results indicate that the introduced system is simple and fast and it leads to better compression gain in comparison with the case of using first order polynomial approximation.
Some esters were prepared from reaction of different molecular weight of PVA with some acid chloride (prepared by reaction of acid with thionyl chloride or phosphorous pentachloride)in the presence of pyridine. The thermal and reological properties were studied. The increasing Of bulky groups decreasing stability of the thermal and reological properties.
Glass Fiber Reinforced Polymer (GFRP) bars have gained popularity as a corrosion-resistant alternative to traditional steel reinforcement in Reinforced Concrete (RC) elements. This study investigates the flexural behavior of PRC panels reinforced with GFRP bars. The study variables included the GFRP reinforcement ratio and the number of embedded steel section distributions. Six concrete panels were fabricated, each measuring 2500 mm in length, with a rectangular cross-section of 750 mm in width and 150 mm in thickness. All panels were reinforced with GFRP bars and divided into two groups based on the reinforcement ratios of 0.532% and 0.266%. For each group, one panel served as the control specimen, while the remaining two were inte
... Show MoreThe article attempts to provide the theoretical fundamentals for the semiotic component of lacunae in a language. The definitions of the following notions have been represented: 1) lacunarity as a complex phenomenon that works in the modes of language, speech and speech behaviour; 2) lacuna as a gap, an empty space, which lacks something, which may be characteristic of a written work. The author of the article considers the main classes of lacunae, among which are: 1) generic lacunae, which reflect the absence of a common name for a class of objects; 2) species lacunae are the absence of specific names, names of individual types of objects or phenomena; 3) intralingual lacunae are found within the paradigms of one language; 4) interlanguage
... Show MoreBackground: The aim of this study was to evaluate the expression of fibroblast growth factor-2 and Heparanase in salivary pleomorphic adenoma, and to correlate the two studied markers with each other and with clinicopathological parameters including: age, sex, tumor site and histopathological presentation. Methods: Sections of twenty five formalin-fixed paraffin embedded tissue blocks specimens of salivary pleomorphic adenoma were immunostained using monoclonal antibodies (Fibroblast growth factor-2 and Heparanase) to assess their expression in this tumor. Results: The expression of fibroblast growth factor-2 and Heparanase were positive in all pleomorphic adenoma cases (100%). The positive expression of fibroblast growth factor-2 was signi
... Show MoreObjective(s): To assess the effect of removable partial dentures on the abutment teeth in comparison with that of the
remaining dentition, and to investigate the effect of regular check up on periodontal health for patients using this
type of prosthesis.
Methodology: One hundred patients wearing removable partial dentures for at least three years included in the
study. Teeth used as direct or in direct retainers for the removable partial denture were considered as the study
group, while the remaining dentition in the same jaw was considered as the control group. The following periodontal
parameters were registered for each tooth, plaque and gingival indices, clinical attachment level and tooth mobility.
Patients were