Background: The fracture of instruments within root canal during endodontic treatment is a common incidence, fracture because of fatigue through flexure occurs due to metal fatigue, this study aimed to assess the effect of curvature angle and rotational speed on the cyclic fatigue of different type of Endodontic NiTi Rotary Instruments and compare among them. Materials and method: Three types of rotary instruments with tip size 0.25: ProTaPer F2 (Densply, Malifier) Revo-S SU( 0.06 taper, MicroMega) and RaCe system (0.06 taper, FKG, Dentaire), Forty file of each instrument were used within two canals with angle of curvature (40 &60 )at two speed (250&400)RPM, twelve group were formed for all instruments(total number=120),ten file for each group. The testing canals customized within stainless steel block covered with glass face, the time to fracture recorded and the mean of cycles to fracture (MCF) detected for each instrument. Data were analyzed statistically by ANOVA, LSD and Independent T-test at 5% significant level. Result: there was a highly significant difference of curvature angle and significant difference of rotational speed on the fracture resistance of instruments. RaCe revealed the best fracture resistance followed by ProTaper then Revo-S that showed the less resistance. Conclusion: The rotary instruments more prone to fracture when used at more curvature angle and higher rotational speed, as well as the rotary instruments differ from each other according to manufacturing process, taper, cross section and other factors.
The research aims to use performance indicators and financial criteria in evaluating the economic feasibility of the company's insurance portfolios. In addition to identifying the strengths and weaknesses in portfolio's performance to enhance the strengths and address the weaknesses. This is consistent with research problem that dealt with the performance indicators, economic feasibility of company's portfolios and contributing to their improvement, reducing the financial and insurance risks associated with company's business. The research’ sample is represented by the Iraqi Insurance Company as it is one of the oldest financial institutions operating in the insurance sector. It has identified (5) insurance portfolios (marine, engineer
... Show MoreWhile providing important news information, News tickers ( also called sliders or crawlers ) have become one of the methods used daily by satellite channels, because it’s almost a continuous news coverage and as it seems, it has become today an addition to the news world. Hence, satellite channels need to look for a mechanism to build news tickers in order to develop them even though they are still today not recognisable and in need of being classified in a radio or television art, and that is not easy. This research sheds light on the construction of the slider of a news satellite channel, which is important according to our modest convictions, as it can be the beginning of a long scientific research in a new field of study. The probl
... Show MoreThe research includes synthesis and identification of novel three amino acids ligands complexes of some heavy metal (II) ions by using the amino acids like glycine, L-alanine and L-valine. New metal mixed ligand complexes with amino acids are prepared the reaction by reacting the three amino acids with the metals(II) chloride by using 50% ethanolic solution and 50% distall water in the molar ratio [1:1:1:1] ( M:Gly:Ala:Val) except for Co(II) and Ni(II) complexes were found after diagnosis the coordination with both Lalanine and L-valine. The prepared complexes identified by using physical properties, flame atomic absorption and conductivity measurements, in addition, mass, FT.IR and UV.vis spectrum as well magnetic moment data. The general
... Show MoreAbstract Lateral Epicondylitis (LE) which has been referred to as the Tennis Elbow as well is a lesion affecting common tendinous origins of wrist extensors due to chronic overuse injury that results in damaging common extensor tendons which join forearm extensor muscles to humerus. The aim of the present evidence-based clinical statement is reviewing scientific evidences for efficacy of a variety of the rehabilitation methods, chronic lateral epicondylitis management. It is focused upon treating chronic lateral epicondylitis and the latest developments in physiotherapy area for managing chronic lateral epicondylitis. Due to the fact that primary physical impairments in the LE are decreased is the strength of the grip, fundamentally due to
... Show MoreThe seed propagation is the predominant method of Echinacea propagation, which has been criticized for its time-consuming control over the separation factor and the uncertainty of pathogen-free plants produced by this method. The technology of tissue culture has provided multiple opportunities for the production of secondary metabolites continuously without being restricted to a specific season, due to the possibility of controlling the environmental conditions and the components of the nutrient medium needed by the plant. This study was conducted to investigate the effects of salicylic acid as elicitor and tyrosine as precursor on propagation and some secondary compounds production in coneflower in vitro. The result showed the superiori
... Show MoreJob stress is considered one of the most important obstacles that may appear in the work field. In order to deal with the obstacles and challenges , the idea to deal with job stress has come to address job stress as one of the most important trends that enable organizations to face those challenges through focusing on the role of job stress and the organizational climate of the organization.
The research deals with two variables: the job stress as an independent variable, and the organizational climate as a dependent one. Each variable includes five sub-dimensions. These dimensions have been involved in an interaction to form
... Show MoreThe accuracy of the skillful performance of the front and back dimensions of badminton in volleyball, occurs through the investment of complex exercises (physical skills) in a single performance and its characteristics that give the correct movement behavior and speed to the accuracy of the performance of the strokes as well as the identification of changes in some physiological indicators of By using these compound exercises. The research problem lies: I found a weakness in the accuracy of the performance of the front and back dimensions strike and diagnosed this through the tests that it conducted on the players to identify and know the problem, and attributed this weakness to a weakness in the necessary physical and skill abilities and t
... Show MoreThe research aimed to test the effect of independent variables career plateaus and workaholism on employees loyalty through the influence of the mediator variable organizational socialization. Descriptive approach with survey style on a sample of managers and executives in the Iraqi Drilling Company in Basra's (123) employees. The most important findings of the research are: the existence of a significant effect of the independent variables career plateaus and workaholism in employees loyalty by having a mediator variable organizational socialization and introduced numerical from recommendations. &nbs
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