Background: Debonding and fracture of artificial teeth from denture bases are common clinical problem, bonding of artificial teeth to heat cure acrylic and high impact heat cure acrylic denture base materials with autoclave processing method is not well known. The aim of this study was to evaluate the effect of autoclave processing method on shear bond of artificial teeth to heat cure denture base material and high impact heat cure denture base material. Materials and methods: Heat polymerized (Vertex) and high impact acrylic (Vertex) acrylic resins were used. Teeth were processed to each of the denture base materials after the application of different surface treatments. The sample (which consist of artificial tooth attached to the denture base at 45 degree) are consist of (80) artificial teeth from the same model of central incisor, they were prepared , treated and bonded to the conventional heat cured and high impact acrylic denture base material then processed. Control group (Group A 40 samples) in which acrylic resins PMMA cured by conventional water- bath processing technique (74°C for 1.5 hours then boil for 30 minutes),the group was subdivided to 20 samples heat cure acrylic and 20 samples high impact acrylic. Experimentalgroups (Group B 40 samples) in which acrylic resins was cured by autoclave at 121°C, 210KPa. For 30min.the group subdivided to 20 samples heat cure acrylic and 20 samples high impact acrylic. For each subgroup, the 20 samples were subdivided according to surface treatment into: 1-Five acrylic teeth without any surface treatment (control). 2- Five acrylic teeth with diatoric preparation (retention grooves). 3- Five acrylic teeth conditioned with thinner. 4- Five acrylic teeth with retention grooves and thinner. Results: Statistical analysis revealed that chemical and mechanical treatment of acrylic teeth improved the shear bond with heat cure and high impact acrylicalsoautoclave processing improvedthe shear bond with acrylic teeth in high impact acrylic. Conclusion: Autoclave polymerization is suggested as alternative method for processing denture base resins. Autoclave polymerization can be easily performed in laboratory conditions. In High Impact Acrylic, there were highly significant differences of autoclave processing technique compared with water bath regarding the shear bond strength with acrylic teeth.
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Due to the deliberate disposal of industrial waste, a great amount of petroleum hydrocarbons pollute the soil and aquatic environments. Bioremediation that depends on the microorganisms in the removal of pollutants is more efficient and cost-effective technology. In this study, five rhizobacteria were isolated from Phragmites australis roots and exposed to real wastewater from Al-Daura refinery with 70 mg/L total petroleum hydrocarbons (TPH) concentration. The five selected rhizobacteria were examined in a biodegradation test for seven days to remove TPH. The results showed that 80% TPH degradation as the maximum value by Sphingomonas Paucimobilis as identified with Vitek® 2 Compact (France).
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The problem of the paper focused on the role of the learning organization in the crisis management strategy, and the extent of the actual interest in both the learning organization and the crisis management and aimed at diagnosing and analyzing that and surrounding questions. The Statistical Package for the Social Sciences (SPSS) program was used to calculate the results and the correlation coefficient between the two main variables. The methodology was descriptive and analytical. The case study was followed by a questionnaire that was distributed to a sample of 31 teachers. The paper adopted a seven-dimensional model of systemic thinking that encourages questioning, empowerment, provision of advanced technologies, and strategic lea
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Flexible joint robot (FJR) manipulators can offer many attractive features over rigid manipulators, including light weight, safe operation, and high power efficiency. However, the tracking control of the FJR is challenging due to its inherent problems, such as underactuation, coupling, nonlinearities, uncertainties, and unknown external disturbances. In this article, a terminal sliding mode control (TSMC) is proposed for the FJR system to guarantee the finite-time convergence of the systems output, and to achieve the total robustness against the lumped disturbance and estimation error. By using two coordinate transformations, the FJR dynamics is turned into a canonical form. A cascaded finite-time sliding mode observer (CFTSMO) is construct
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Lactiplantibacillus plantarum, one of lactic acid bacteria (LAB), is found in various foods, including dairy products, meat, and vegetables, and most of these bacteria offer beneficial effects to humans and animals as potential probiotics with broad-spectrum antimicrobial activities. The aim of this study was evaluating the antibacterial efficacy of L. plantarum against some foodborne bacteria isolated from dairy products. This research involved 34 dairy products, including local and imported milk, cheese, and yogurt sold locally in Baghdad province, Iraq, during May 2022. For the isolation of L. plantarum, a special medium called MRS (de Man Rogosa and Sharpe) was applied. Colonie
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Persistence of antibiotics in the aquatic environment has raised concerns regarding their potential influence on potable water quality and human health. This study analyzes the presence of antibiotics in potable water from two treatment plants in Baghdad City. The collected samples were separated using a solid-phase extraction method with hydrophilic-lipophilic balance (HLB) cartridge before being analyzed. The detected antibiotics in the raw and finished drinking water were analyzed and assessed using high-performance liquid chromatography (HPLC), with fluorometric detector and UV detector. The results confirmed that different antibiotics including fluoroquinolones and
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