Background: Thermocycling simulates the temperature dynamics in the oral environment. This in vitro study done to measure and compare the effect of thermocycling on the shear bond strength of stainless steel and sapphire brackets bonded to human enamel teeth using light cured orthodontic adhesive and debonded at various time, and to measure adhesive remnant index after debonding. Materials and Methods: one-hundred-twenty extracted upper first premolars for orthodontic reason were used in this study; depending on weather thermocycled or not, the sample was divided into two main groups, then within each group 30 teeth were used for stainless-steel brackets (Bionic®) and for sapphire brackets (Pure®). Both groups were subdivided into three groups (n = 10) according to the debond times: I: debond after 24 hour, II: debond after 7 days and III: debond after 30 days. Within 24 hr, half of the sample was thermocycled manually for 500 complete cycles between 5/55°C and the remaining sample was stored in distilled water at room temperature and water was changed daily until debond time for each group was performed. The adhesive remnant index was tested under 20X magnification lens using stereomicroscope. Results and Conclusions: Both bracket types demonstrated high shear bond strength values before thermocycling (P?0.05), whereas after 500 thermocycles, there were significant changes in shear bond strength resulted in marked reduction in the stainless steel brackets than in the sapphire brackets (P?0.05). Shear bond strength values increased with time for both stainless steel and sapphire brackets with and without thermocycling (P?0.05). The tendency of bond failure was increased at the bracket/adhesive interface rather than enamel/bracket interface in the stainless steel brackets whereas at the enamel/bracket interface rather than bracket/adhesive interface in the sapphire brackets.
Ubikh is one of the most important tribes of the Northwest Caucasus and has a long history. Naturally, rebukes are an integral part of the Caucasus region. Their people were able to confront the Russian invasion of their lands like the rest of the Caucasus tribes to defend their existence, freedom and the right to build their independent state, but they were not able to resist the great Russian military progress they achieved on all sides. For the territory that belonged to Persia and the Ottoman Empire and ended the resistance of the Meridian movement in the Northeast Caucasus, the Russians left only the weak resistance of the tribes of the Northwest Caucasus led by the rebuke after Russia managed to eliminate all resistance movements i
... Show MoreEconomic performance is one of the most important indicators of economic activity and with the performance of the economy progress varied sources of output and increase economic growth rates and per capita national income, and to recover the business environment and increase investment rates and rising effectiveness of the financial and monetary institutions and credit market. Which leads to increased employment rates and reducing unemployment rates and the elimination of many of the social problems and improve the average per capita income as well as improve the level of national income.
The input / output tables is a technique mathematical indicates economic performance
... Show MoreThe researcher attempts to examine Barman model in acquiring the historical concepts among fourth-grade students at literary classrooms. To this end, the researcher held the null hypothesis, there is no significant difference between the experimental groups who was taught based on Barman model and the control group that taught based on the traditional method in acquiring the historical concepts on the post-test. To testify the effectiveness of Barman model, the researcher administered a questionnaire included (60) items on bunch of female-students who were selected from al-khamaeal preparatory school in al-hurriyah district in Baghdad. The author utilized different statistical tools to analyze the collected data. &
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In light of globalization and internationalization of financial markets, issues arising from financial crises have become increasingly serious and fundamental, creating a lot of debate among experts around the world. So, many studies have attempted to investigate what measures can be taken to detect and prevent crises before they devastate the economies.
Therefore, this paper examines the Effectiveness of the Monetary Policy (MP) to Avoid, Reduce or Treat the Financial Crisis in Malaysia. Scholars have yet to agree on the issue
... Show MoreThe current study monitors the mechanisms of formation of the actor's performance expressive system (voice and motion) and the levels of their construction consistent with the aesthetic premise of the theatrical performance through incorporating what is natural, materialistic (physiological) and artistic and philosophical virtual (aesthetic ), through which the creative actor seeks not to repeat the image and substance of a thing according to its natural life image, in favor of new aesthetic reproduction governed by a group of significant relationships formed according to (artistic and philosophical) characteristics and features that distinguish the artistic accomplishment from its reality(its natural and functional reference). According
... Show MoreIt has aimed by this research at presenting new interpretations to diversification phenomenon and its possible effects on firm value. These interpretations are culminated by the disclosure of the distinct role of resource-based view in the study of relationship between diversification strategy and firm value. The study has conducted on a sample consisted of the largest American companies listed in Fortune 500 along with seven years period
(2005-2011). This first local attempt, which has based on panel dat--a analysis for interpreting an expected variance of firm value due to diversification strategy, may helps with a clear vision to solve the contradiction and confusion surrounded the true linkages between t
Abstract:
The paper aims to measure an aggregated banking stability index reflecting the degree of stability of the banking system to help policy makers to take the necessary actions to avoid financial crises facing banks and to achieve a banking system with high efficiency in terms of banking risk.
Therefore, the problem of paper is that the Central Bank of Iraq did not seek until 2016 to build a aggregated index for the purpose of identifying the stability of the banking situation in Iraq, but rather on the adoption of scattered indicators, which depend on the mechanism of relative changes in those indicators for the purpose of identifying the situation of b
... Show MoreThis study aimed to evaluate the preparedness and adherence of community pharmacists to the International Pharmaceutical Federation (FIP) Health Advisory COVID-19 guidelines for pharmacists (July 2020) during COVID-19 pandemic. This was a cross-sectional study based on electronic survey using google form, which was distributed from November 19, 2020 to January 1, 2021 using social media platforms. The survey measured 21 pharmacy preventive measures (PM). A multivariate regression analysis was used to identify factors influencing pharmacy implementing of PM. Hand disinfection after serving patients represented the main adopted measure (89.3%). Surprisingly, only 35.4% of participants implemented the proper ways of hand disinfection during fa
... Show MoreThe deliberative system of communicative studies is exposed to cultural openness, according to modern cultural studies, to establish a verbal language system that achieves reciprocal and cross-cultural relations. This research has examined the concept of deliberative approach in the contemporary Iraqi theater text by studying the deliberative system of text and its interrelationship with The stage of the verbal embodiment of the dramatic event, because the dramatic text achieves in its construction of racism, a deliberative approach between the verbal event and the language, and what later leads to the completion of the dramatic action. The research included four chapters. The first chapter was the systematic framework of the research, T
... Show MoreThe article describes a certain computation method of -arcs to construct the number of distinct -arcs in for . In this method, a new approach employed to compute the number of -arcs and the number of distinct arcs respectively. This approach is based on choosing the number of inequivalent classes } of -secant distributions that is the number of 4-secant, 3-secant, 2-secant, 1-secant and 0-secant in each process. The maximum size of -arc that has been constructed by this method is . The new method is a new tool to deal with the programming difficulties that sometimes may lead to programming problems represented by the increasing number of arcs. It is essential to reduce the established number of -arcs in each cons
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