Background: Elastomeric chains are one of the most commonly used force delivery systems. They have the ability to exert a continuous force, convenience of use, compatibility to oral environment and cost effectiveness but one of the inherited disadvantages is force degradation. Materials and methods: This in vitro study was designed to evaluate the effect of alcohol presence in mouthwashes on force decay of different configurations of clear elastomeric chains from (Ortho Technology company) which are: closed , short and long under the effect of time at (Initial, 1, 2, 3 and 4 weeks) intervals with exposure to different chemical solutions. A total (540) modules of elastomeric chains of three different types (long, short and closed) transparent in color, with an initial length (19mm) and about 50% extension (29mm) were used for the study. These elastomeric chains divided in to four groups and exposed to different chemical solutions (Listerine Original alcoholic mouthwash, Listerine Zero alcohol mouth wash, Ethanol 26.9%, distilled water) twice daily for 60 seconds according to manufacturer instructions to measure the amount of force degradation in different time intervals. These elastomeric chains were incubated in covered glass containers at 37C˚ for the entire testing period. Results: Statistical analysis showed that there was a highly significant difference in the mean percentage of force decay (P≤ 0.001). For all chemical solutions the highest percentage of force decay occurs in Listerine Original Alcoholic mouth wash. Also in all chemical solutions closed elastomeric chains has the least percentage of force decay. While closed configuration have the highest percentage of force decay. Conclusion: We can conclude that alcoholic mouth wash(Listerine Original) causes increase force degradation of all types of elastomeric chains while alcohol free mouth wash (Listerine Zero) causes less force degradation of all types of elastomeric chains. Also closed configuration elastomeric chains have the least percentage of force decay than other configurations.
Coaxial (wire-cylinder) electrodes arrangements are widely used for electrostatic deposition of dust particles in flue gases, when a high voltage is applied to electrodes immersed in air and provide a strongly non-uniform electric field. The efficiency of electrostatic filters mainly depends on the value of the applied voltage and the distribution of the electric field. In this work, a two-dimensional computer simulation was constructed to study the effect of different applied voltages (20, 22, 25, 26, 28, 30 kV) on the inner electrode and their effect on the efficiency of the electrostatic precipitator. Finite Element Method (FEM) and COMSOL Multiphysics software were used to simulate the cross section of a wire cylinder. The results sh
... Show MoreThe Historical effect of Conflict between North and South
The effects of solar radiation pressure at several satellite (near Earth orbit satellite, low Earth orbit satellite, medium Earth orbit satellite and high Earth orbit satellite ) have been investigated. Computer simulation of the equation of motion with perturbations using step-by-step integration (Cowell's method) designed by matlab a 7.4 where using Jacobian matrix method to increase the accuracy of result.
Abstract
The current research aims to develop a guidance program suitable for high school students and apply it to them in order to ensure the reduction of addiction to the use of different means of communication. The researchers used the scale of addiction to the means of communication (SAS) to measure the level of addiction as well as to identify the impact of the proposed guidance program in reducing the degree of addiction to communication. It was applied to a sample of (20) female students divided equally into two groups: an experimental group of (10) female students and a control group of (10) female students from the secondary level in a school under the department of education in the education of the alma
... Show MoreIs the subject of environmental analysis of the important issues that should occupy the attention of the departments of banks in general and banks in particular, the research sample, regardless of their size and the nature of its activity, So if the current era and witnessing rapid developments and changes, making the banking environment is more complex and interconnected than ever, And it became not possible for banks to be aware and understand the external environment variables without an analysis of the various constituent elements and influential heavily in its financial and administrative,Therefore research aims to find out the relationship between the external environment and banking facilities analysis application on the Rafidain
... Show MoreThe study aims at investigating the quality of internal auditing and its impact on nature, timing, and procedures of external audit, based on international auditing standards, in particular ISA (610). The standard ISA (610) requires the external auditors to assess independence, the scope of internal audit unit, competence, and due professional care of internal auditors as indicators that reflect the quality of internal audit performance before deciding to rely on internal auditors.
The sample of this study consisted of external auditors in Iraqi Solidary Companies for Auditing. A questionnaire was distributed to them via e-mail
... Show MoreThe study aims to identify the impact of the implementation of the integrated education strategy in the curriculum of the Arabic language for the seventh grade on the academic achievement in the schools of the capital Amman. The researcher adopted the experimental method, where two divisions of the seventh grade students were chosen from the secondary school for girls. The sample of the study was 60 students divided into two equal groups: 30 students represented the experimental group (A) and (30) students represented the control group. To collect the needed data, a test of (40) Multiple Choices was used. The results showed statistically significant differences between the mean scores of the experimental group who were taught acc
... Show MoreRecently, that there has been a decline in the levels of female players for this event in recent years compared to developments in the world, as this activity depends to achieve the highest level of performance on the physical capabilities and physiological indicators of the player who It is reflected in the achievement, which results in the loss of time for Iraqi female runners compared to the world champions in the (100) meter hurdles competition, which reflects on the level of achievement. The two researchers used the experimental approach in addressing the research problem, and the experimental design used the method of the two equal groups, the two experiments with the pre and post-tests. Female runner and second experimental group (4)
... Show MoreA theoretical and protection study was conducted of the corrosion behavior of carbon steel surface with different concentrations of the derivative (Quinolin-2-one), namely 7-Ethyl-4-methyl-1-[(4-nitro-benzylidene)-amino]-1H-quinolin-2-one (EMNQ2O). Theoretically, Density Functional Theory (DFT) of B3LYP/ 6-311++G/ 2d, 2p level was carried out to calculate the geometrical structure, physical properties and chemical inhibition chemical parameters, with the local reactivity in order to predict both the reactive centers and to know the possible sites of nucleophilic and electrophilic attacks, in vacuum and two solvents (DMSO and H2O), all at the equilibrium geometry. Experimentally, the inhibition efficiencies (%IE) in (3.5% NaCl)
... Show MoreA study of interactivity in the Iraqi newspaper sites_ An analytical study of the website of Al-Mada, Al-Zaman, Al-Sabah and Tariq Al-Shaab newspaper sought to determine the amount of interactivity in the sites of Iraqi newspapers that have been published since 2003, which consists of (15) newspapers according to the statistics of the Iraqi Books and Documents House.
and the researcher conducted an analytical survey on these sites, and the percentage of interactivity in general was weak, not more than (47.1%), and this weakness in interactivity contributed greatly to the decline in surfers of the websites of those electronic newspapers.
The highest aggregate rate of the research sample was in the simple interactive tools
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