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.
This research deals with the color bias and its effect on maids in Mississippi in Kathryn Stockett''s (2003) The Help. The ill-treatment and negligence of Afro-American maids received from the white women who employed them in Mississippi that must have affected directly or indirectly on their personality and may eventually lead to suffering. They live in an atmosphere of struggle to free themselves from the complicated relationships between black and white. Afro-American maids pledged to liberate themselves from social oppression by protesting through writing a book which chronicles their stories in slave masters’ homes to make their presence felt as human being equal to their white masters.
The issue of the other in the graphic design and specifically the advertising constitutes a cognitive study of the structure of the intellectual expansion in the cognitive and intellectual creative systems because of the implicit and declared embodiment it provides within the mechanisms of reading in the advertising design that appeared according to the other and through the embodiment of the textualism, the difference and the binary opposites is nothing but a reaction to the design thought and what constitutes of the manifestations of the other in advertising design. Based on the above, we review this study (Manifestations of the Other in Graphic Design) to clarify the topic through four chapters. The first chapter included the research
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The research, which was drawn from his doctoral thesis (People's Policy towards Vietnam 1949-1979), discussed the roots of the connections between the Chinese and Vietnamese communists since the 1920s, the presence of Ho Chi Minh and other Vietnamese communists in China, their influence by the revolutionary struggle of the Chinese Communist Party and their establishment of a group of The Vietnamese Revolutionary Societies and the Indo-Chinese Communist Party until the outbreak of the Vietnamese Revolution and their success in declaring the establishment of the Democratic Republic of Vietnam in 1946. Keywords: Ho Chi Minh, Chinese Communist Party, Indo-Chinese Communist Party, Democratic Republic of Vietnam, Chou En Lai.
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من أجل فهم دور سلطنة عُمان في المفاوضات الإقليمية والوساطة وحل النزاعات يجب تقدير سياستها الخارجية، والتي سيتم تقييمها من أجل فهم كيفية نشأتها وتشكلها وأثر ذلك على مواقفها السياسية طوال سنوات حكم السلطان الراحل قابوس بن سعيد. وتقع عُمان في منطقة مضطربة، وقد طُلب منها في عدة مناسبات أن تعمل كمفاوض أو وسيط في الصراعات الإقليمية. سيبحث هذا البحث في كيفية قيام السلطنة بالوساطة الدولية، خاصة في الصراع الأمريكي
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The aim of this research was to evaluate the level of ball control in basketball. There was a great weakness in ball control that affected the mastery of many skills that affect the success of the team. The researcher also found a lack in training programs concerning ball control. The researchers used (9) special tests for ball control out of (41) test applied on young basketball players were (86). The researchers concluded that: 1. Criteria were set for test results of ball control. 2. A level of criteria was set for test results of ball control.
A series of laboratory model tests has been carried out to investigate the using of pomegranate sticks mat as reinforcement to increase the bearing capacity of footing on loose sand. The influence of depth and length of pomegranate sticks layer was examined. In the present research single layer of pomegranate sticks reinforcement was used to strengthen the loose sand stratum beneath the strip footing. The dimensions of the used foundation were 4*20 cm. The reinforcement layer has been embedded at depth 2, 4 and 8 cm under surcharge stresses . Reinforcing layer with length of 8 and 16 cm were used. The final model test results indicated that the inclusion of pomegranate sticks reinforcement is very effective in improvement the loading cap
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An approximate solution of the liner system of ntegral cquations fot both fredholm(SFIEs)and Volterra(SIES)types has been derived using taylor series expansion.The solusion is essentailly
The research aims: to build a measure of the cognitive competence of coaches from the point of view of players of Iraqi Premier League volleyball clubs and extract scores and standard levels for it. In order to achieve the objectives of the research, the descriptive method was used using the survey method. As for the research sample, it was chosen intentionally, and was represented by volleyball players for the Premier League 2024-2025. The sample was divided into exploratory, constructive, and standardizing, and starting the construction procedures, which included finding the scientific foundations for the scale, in addition to extracting the modified standard score and levels for the sample of the main experiment for standardization. Amou
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