Background: The microhardness of a composite resin is a vital parameter that is used to determine its clinical behavior. Measuring the microhardness of a composite resin has been used as an indirect method to assess its degree of conversion and extent of polymerization. The purpose of this in vitro study was to evaluate the effect of three curing distances (0, 2, and 4 mm) on the microhardness of the top and bottom surfaces of three types of flowable bulk-fill composite resins (smart dentin replacement, Opus bulk fill flow, and Tetric N). Material and method: Sixty-three specimens from the three types of composite resins (n=21) were fabricated using Teflon mold with a 4mm depth and a 5 mm internal diameter and cured for 20 seconds. For each material, three subgroups were fabricated according to the position of the light curing tip from the top surface; at 0, 2, and 4 mm distances. Microhardness was measured using the Vickers test with a 50-g load for 15 seconds for the top and bottom surfaces of all the samples. Results: The microhardness values were decreased in the following order; 0mm > 2mm > 4mm curing tip distance, for both sides and Tetric N had the highest microhardness values. Significant differences in microhardness were recorded between the top and bottom surfaces for all the specimens (p<0.05). Conclusion: Increasing the distances between the tip of the light cure and the surface of flowable bulk-fill resins can significantly decrease the microhardness of the bottom surfaces compared to the top surfaces.
In this numerical study a detailed evaluation of the heat transfer characteristics and flow structure in a laminar and turbulent flow through a rectangular channel containing built-in of different type vortex generator has been a accomplished in a range of Reynolds number between 500 and 100,000.A modified version of ESCEAT code has been used to solve Navier-Stokes and energy equations. The purpose of this paper is to present numerical comparisons in terms of temperature, Nusselt number and flow patterns on several configurations of longitudinal vortex generator including new five cases. The structures of heat and flow were studied, using iso-contours of velocity components, vortices, temperature and Nusselt n
... Show MoreThe literature shows conflicting outcomes, making it difficult to determine how e-learning affects the performance of students in higher education. The effect of e-learning was studied and data has been gathered with the utilization of a variety of qualitative and quantitative methods, especially in relation to students' academic achievements and perceptions in higher education, according to literature review that has been drawn from articles published in the past two decades (2000-2020). The development of a sense of community in the on-line environment has been identified to be one of the main difficulties in e-learning education across this whole review. In order to create an efficient online learning community, it could be claim
... Show MoreThe current research aims to identify the risk management and its impact on the quality of service in the Salahalddin Sewerage Directorate, This is due to the great impact that the service provided by this institution plays in preserving health and the environment in the community, which has faced many administrative challenges, problems and issues as a result of the rapid and continuous environmental changes, and therefore, the adoption of administrative concepts such as risk management and knowledge of their impact on the quality of the municipal service is necessary to reach this service To the required levels. To achieve the research objectives, two main hypotheses have been formulated, the first of which is to find the extent of the li
... Show MoreObjectives: the study aims to findout the effectiveness of educational program concerning infection control guideline on nurses, and to find out the relationship between effectiveness of program and types of hospital unit, age, level of education, and years of experience of nurses. Methodology: A quasi-experimental design study was carried out in Baghdad teaching hospital in the wards, for the period of December, 20th 2013 to September, 30th of July 2014, The study samples is composed of (60) nurses who have been actually working in the medical ward, blood disease, psychiatric ward, and neurological war
The aim of the study was to study the implications of the strategic direction on organizational performance. The research was carried out in the Iraqi Ministry of Defense / Inspector General's Office for the purpose of identifying the nature of the relationship and the impact between the two variables. A sample of 60 people managers, department managers and directorates was targeted.
The researcher tried to test hypotheses in the first chapter, which was devoted to the methodology of research and previous studies and found the following: (1) validity of the first hypothesis of the existence of a relationship of positive significance of the strategic direction in its sub-dimensions with organizational perf
... Show MoreIntroduction: Knowledge management plays a crucial role in students’ ability to acquire, organize, retrieve, and apply information, impacting academic performance. In sports sciences, especially in combat sports like boxing, effective knowledge management supports both theoretical understanding and practical skill application. Despite exposure to boxing through training and media, students’ academic performance remains inconsistent. Objective: This study examines the relationship between knowledge management and cognitive achievement among second-year students in the College of Physical Education and Sport Sciences at the University of Basrah. It evaluates how students manage knowledge and its impact on their retention and application
... Show MoreThe agricultural activity has a great significance in the all four dimensions of sustainable development. Firstly, the economic dimension which it contributes with the GDP, as well as, it is considered as an important source to attract the investment. Secondly, the environmental dimension which also contributes with conserving of the biodiversity, combating the desertification, and increasing the farmlands. Thirdly, for its role in the social dimension to achieve the food security, to eradicate the poverty, and providing jobs. Fourthly, toward the institutional dimension as well it is considered as a source that allows all people to participate effectively, and to exchange of the local and universal experiences and perspectives. For conf
... Show MoreFinancial markets play an important role in the economy, as it contributes to the financial and economic system of the state stability, as it reduces the adoption of the companies on the loans granted by the banks, as financial markets contribute to attracting and channeling savings to small savers who will be able to buy a number of shares proportional to their savings, It also provides them the place of exchange, and play technology and information systems an important role in facilitating exchanges and increased market activity, in this research touched on the importance of information technology in effect on the activity of the financial markets. Research is divided into three demands of the first concept of eating and the importance
... Show MoreThe Islamic Bank of Al-Nahrain offers a formula for financing the purchase of real estate through a deferred sale contract, through Murabaha to the order to buy, and the payment of the price is in the form of instalments that include (the purchase price of the profit and the mutual agreement on the real estate). This research aims to show the reflection of real estate murabaha on the bank's investments, by measuring the effect of real estate murabaha on the profits achieved by the Islamic Bank of Al-Nahrain Bank. The growth of 'real estate murabaha' realized from the 'amounts granted by Bank X, in addition to analyzing the financial ratios of profitability indicators, including (return on deposits Y2) and for the years (2016 - 20
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