Background: The demand for better esthetic during orthodontic treatment has increased nowadays, so orthodontists starting using esthetic arch wires, brackets and ligatures.Tooth colored brackets were introduced in different types of materials. Sapphire ceramic brackets are one type of esthetic brackets and their color stability remains the main concern for the clinicians and patients at the same time. The present study design to evaluate the effect of three different staining materials (pepsi, black tea and cigarette smoke) on the stainability of sapphire ceramic brackets bonded with three types of light cure orthodontic adhesives which include: Resilience, Enlight and Transbond. Materials and Methods: The sample consisted of three hundred sixty sapphire brackets. The brackets were divided according to bonding materials into three groups each group consist of one hundred twenty brackets, then each subgroup farther subdivided into four groups according to the material they were immersed (distilled water, black tea, Pepsi and cigarette smoke) with thirty brackets each, then Each group with ten brackets farther subdivided according to time interval of immersion in each media into three groups one day, seven days and fourteen days at 37°C in the incubator.A UV-Visible spectrophotometer (Shimadzu, UV -1800) was used to perform a light absorption test. Results: ANOVA and LSD post Hoc tests were used to identify the significant effects of the staining materials at a significance level P ≤ 0.05.It was found that the immersion time gradually influenced the color stability of the adhesive materials with sapphire brackets with the highest activity observed at fourteen days interval. The brackets bonded with Resilience light cure adhesive are the most type affected by staining materials, then followed by the brackets bonded with Transbond and finally the brackets bonded with Enlight light cure adhesive. For the staining materials it was found that the cigarette smoke is the most powerful staining material, followed by tea and finally pepsi. Conclusions: From the above result we can conclude that the type of adhesive must take in consideration when the esthetic brackets have been used.
<span lang="EN-US">Iraqi people have been without energy for nearly two decades, even though their geographic position provides a high intensity of radiation appropriate for the construction of solar plants capable of producing significant quantities of electricity. Also, the annual sunny hours in Iraq are between 3,600 to 4,300 hours which makes it perfect to use the photovoltaics arrays to generate electricity with very high efficiency compared to many countries, especially in Europe. This paper shows the amount of electric energy generated by the meter square of crystalline silicon in the photovoltaic (PV) array that already installed in 18 states in Iraq for each month of the year. The results of the meter-square of PV arr
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Semliki Forest Virus (SFV), a member of the Alphavirus genus in the Togaviridae family, is a small-enveloped, positive-sense single-stranded RNA (+ssRNA) virus. The virus is spread by mosquitos and can infect humans, resulting in mild febrile disease with symptoms that include fever, myalgia, arthralgia, persistent headaches and asthenia. Virulent strains of SFV in mice cause lethal encephalitis by infecting neurons in the central nervous system. In on-going experiments in the research group using a focused siRNA screen we have investigated the role of deubiquitylases (DUBs) during SFV infection (as a model alphavirus) and monitored the effect of DUB depletion on cell viability after infection. We identified a group of DUBs that h
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Abstract:
The research aims to clarify the impact of adopting the IFRS16 financial reporting standard on lease contracts in insurance companies on audit procedures. The change in the classification of lease contracts in the case of adopting the IFRS16 financial reporting standard necessarily requires audit procedures that are compatible with this change. A proposed audit program was prepared, guided by international auditing standards, based on the study of the client's environment and analysis of external and internal risks in the light of financial and non-financial indicators. The researchers reached a set of concl
... Show MoreThe security environment for Northeast Asia is extremely important, as it includes most of the international actors (United States of America, China, Russian Federation and Japan), which gives the nature of the interactions of these forces a special importance for the region.
Because of the multiplicity of policies and interests of the active forces in the region, the result has been an unstable regional environment where the interests of the major powers often clash repeatedly on many related issues, which is coupled with the growing efforts of many powers to adopt policies that differ from what they did in the past This resulted in different patterns of relations, which were mainly characterized by competition over regional lea
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Soil is the cardinal resource for agricultural crops. Healthy soil will produce healthy plants. Since healthy soil is the important goal for the farmers, they need to select the best tillage system to achieve that goal. There are two main types of tillage systems. Conservation tillage (no-tillage farming) uses agricultural machinery that performs a double function; tillage and seed farming simultaneously. In contrast, conventional tillage farming uses multiple agricultural machines to till and seed the soil. The farmers in the northern governorates of Iraq have used the conservation farming system for a long time. However, the farmers who live in the middle and southern governorates in Iraq use conventional tillage farming. Because most of
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The debate on the methodology of media and communication research is no longer subject to the logic of the contradiction between the quantitative and the qualitative approach, nor the logic of the comparison between them. The nature of the topics presented for research, the problems they raise, the goals to be achieved from the research, and the epistemological positioning of researchers are among the critical factors that dictate the appropriate approach or methodological approaches to conduct their research. This positioning means the implicit philosophical principles upon which any researcher relies and which determine the path he/ she takes to produce scientifically approved knowledge. The method of the researcher's access to the phe
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The aim of this study is to uncover the views of female students of Shaqra University towards midterm tests. A survey of (42) items distributed in three fields. The study has been applied to a random sample of (421) students from two faculties. The results showed that all three fields have achieved an intermediate level. The results also indicated that there were no statistically significant differences in students’ views of midterm tests due to the specialization or academic level variables.
Autoimmune hepatitis is an inflammatory disease and its incidence has been increasing. The features of hepatitis are the release of inflammatory cytokines, the elevation of AST and ALT, and hepatocyte apoptosis and necrosis. Concanavalin A considered as essential model represents the acute immune-mediated liver damage in rodents. Thymoquinone is well known herbal compound that exert hepatoprotective, anti-inflammatory, and antioxidant activity. In this study, we focus on the immunoregulatory and liver protective effect of thymoquinone in a mouse model of concanavalin A-induced liver injury.
Twenty-four male mice were randomly divided into four groups each containing six animals: Negative control group, concanavalin A model group,
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The research aimed to identify smart management capabilities of secondary school principals in education directorates in Baghdad according to the administrative intelligent and leadership competencies. The study used incentives as a descriptive method, by analyzing five main areas of smart management: strategic planning, self-awareness, skills, organization and culture. A purposive sample consisting of 102 secondary school principals from education directorates (Rusafa1) and (Karkh2), was taken to fill questionnaire the latter representing a complete sample of the target population. validated has been built an advanced measurement tool composed of 56 items across the five domains of strategic planning (21%), self-awareness (21%), culture (2
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