Objectives: The purpose of this in vitro study was to compare the effect of adding a poloxamer surfactant to the irrigant solutions on its cleaning efficiency. Design: In this study the roots of extracted permanent premolar teeth were used and evaluated by using Scanning Electronic Microscopy (SEM). Materials and Method: 72 human single tooth of permanent premolar (8 for each group) were used in this in vitro study. Roots after sectioning at cervical area to get 15 mm were embedded in a plastic container filled with impression silicon, then instrumented with ProTaper rotary instruments till size F4. Each group (8 root) were irrigated with one of the nine solutions used in study: three concentrations of NaOH [5% (A1), 2.5%(A2), 0.5%(A3)], three concentrations of NaOH with Poloxamer surfactant [5% (B1), 2.5% (B2), 0.5% (B3)], NaOCl 5.25% (C1), NaOCl 5.25% with Poloxamer surfactant (C2), and Normal Saline (D). After instrumentation, each tooth was finally washed with normal saline. Then by using diamond disc, all roots were sectioned longitudinally in buccolingual direction to obtain two halves of each root, the more intact root was selected to be prepared for scanning electron microscopy test. Finally, the data was analyzed by using the SPSS 25 program with a non-parametric Kruskal-Wallis test. Additionally, scores were analyzed by using the chi-square test. The significance level for all tests was set at p ≤ 0.05. Results: the study showed that Sodium hypochlorite was higher in smear layer removal than that of Sodium hydroxide, and there was also a significant increase in the cleaning efficiency of sodium hydroxide with increasing concentration of solutions. Conclusion: The adding of a poloxamer surfactant didn't significantly increased the cleaning efficiency of both solutions used. No significant difference between NaOCl and NaOH
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This paper presents the study and analysis, analytically and numerical of circular cylindrical shell pipe model, under variable loads, transmit fluid at the high velocity state (fresh water). The analytical analysis depended on the energy observation principle (Hamilton Principle), where divided all energy in the model to three parts , strain energy, kinetic energy and transmitted energy between flow and solid (kinetic to potential energy). Also derive all important equations for this state and approach to final equation of motion, free and force vibration also derived. the relations between the displacement of model function of velocity of flow, length of model, pipe thickness, density of flowed with location coordinate x-axis and angle
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This study aims to explore the potential mediation role of person-centeredness between the effects of the work environment and nurse reported quality and patient safety. A quantitative cross-sectional survey collected data from 1055 nurses, working in medical and surgical units, in twelve Malaysian private hospitals. The data collection used structured questionnaires. The Hayes macro explored the mediation effect of person-centeredness between the associations of work environment dimensions and care outcomes, controlling nurses’ demographics and practice characteristics. A total of 652 nurses responded completely to the survey (61.8% response rate). About 47.7% of nurses worked 7-h shifts, and 37.0% were assigned more than 15 pati
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This study examined the effect of essential oils extracted from peel of Citrus paradisi and Citrus sinensis on two species of fungi: Penicillium oxalicum and Fusarium oxysporum as well as effect of two fungicides: Carbendazim and Thiophanatemethyl against above fungi. Results showed that the essential oil of Citrus paradisi inhibited the radial growth of Penicillium oxalicum and Fusarium oxysporum at concentration 4%. Nevertheless, the essential oil of Citrus sinensis inhibited the radial growth at concentration 5 and 4%, respectively. Furthermore, the two studied fungicides inhibited radial growth of these fungi too. Therefore, there are a positive relationship between the evaluating of concentration and the percentage of inhibiting of rad
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he effect of different cultural conditions on production of bioemulsifier from Serratia marcescens S10 was determined; different carbon and nitrogen sources were used such as: different oils include: edible (vegetable) oils (olive oil, sesame oil, sun flower oil and corn oil) and heavy oils (oil 150, oil 60, oil 40) as carbon sources and (NH4Cl, casein, (NH4)2SO4, peptone, tryptone, gelatin and yeast extract) as nitrogen sources were added to production media. Bioemulsifier was estimated by measuring the surface tension (S.T), emulsification activity (E.A) and emulsification index (E24%). The best results of bioemulsifier production from Serratia marcescens S10 were obtained at pH8 and incubated at 37ºC for 5days, using sesame oil
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In this paper, we used two monomers, 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA) and m,m'-diaminobenzophenone (m, m’-DABP), to produce polyamide acid and then converted it to polyimide (PI). The effects of phosphoric acid (H3PO4) molarity (1, 2, and 3 M) on the structural, thermal, mechanical, and electrical characteristics of the polyimides/polyaniline (PI/PANI) nanocomposites were studied. Two sharp reflection peaks were developed by the addition of PANI to PI. When 3 M H3PO4 is added, the crystalline sharp peak loses some of its intensity. The complex formation of PI/PANI-H3PO4 was confi
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