Abstract: Objectives: To investigate the effect of temperature elevation on the bonding strength of resin cement to the zirconia ceramic using fractional CO2 laser. Background: Fractional CO2 laser is an effective surface treatment of zirconia ceramic, as it increases the bonding strength of zirconia to resin cement. Methods: Thirty sintered zirconia discs (10 mm diameter, 2 mm thickness) were prepared and divided to three groups (N=10) and five diffident pulse durations were used in each group (0.1, 0.5, 1, 5 and 10 ms). Group A was treated with 10 W power setting, group B with 20 W and group C with 30 W. During laser irradiation, temperature elevation measurement was recorded for each specimen. Luting cement was bonded to the treated zirconia surfaces and cured for 30 seconds. Shear bond strength was evaluated by a testing machine (universal) with bond failure mode determination. Results: The lowest temperature elevation measurement of the irradiated specimen which gave maximum shear bond strength was about 1.6±0.3 Ċ higher than ambient room temperature (27±0.2 ºC). Apparent micromechanical irregularities were seen in the treated samples and cracks formation with increased pulse duration and power setting were also observed. Conclusions: The temperature elevation is a vital factor in the surface roughness of zirconia ceramic with fractional CO2 laser irradiation and the lowest temperature elevation at best shear bond strength of zirconia ceramic to the resin cement is satisfied with the shorter pulse duration of 0.1 millisecond.
This research dealt with the subject of auditing bank credit risks in accordance with international auditing standards and aims to develop procedures and design a credit risk audit program in accordance with international auditing standards and demonstrate their impact on the truth, truthfulness and fairness of financial statements and on their overall performance and continuity in the banking sector Its importance lies in relying on international auditing standards to assess and measure bank credit risk and its impact on the financial situation as well as the ability to predict financial failure. A set of conclusions have been reached, the most important of which is that the bank faces difficulties in measuring credit risk in accordance
... Show MoreThe study aims to introduce at the difficulties in which delay the using of the internet In the educational process – learning , Study was conducted on a sample of students in the College of Education for Girls and the effects of variables : possession of computer , availability of the internet service , and the level of parents on these difficulties , Used for this purpose, a total sample size (400) students, distributed Departments . Results showed that the most important difficulties in which delay using of internet were : Lack of knowledge of internet availability , Lack of knowledge of the aim of using this service , and the students satisfaction that the disadvantages is more than the advantages of
... Show MoreThe study aimed to explore the school principals’ servant leadership practices for primary teachers’ perspectives in the Sultanate of Oman, furthermore to investigate the differences in those practices attributable to variables (gender, qualification, educational stage, years of experience, governorate). The study relied on the descriptive approach, by employing the survey research design using the questionnaire as a main tool for data collection, which included five dimensions of servant leadership (altruism, humility, enhancing teacher development, emotional healing, commitment to community development), Data collected from (1094) teachers in basic education schools, and they were chosen randomly. The results of the study indicated
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Abstract:In this paper, some probability characteristics functions (moments, variances,convariance, and spectral density functions) are found depending upon the smallestvariance of the solution of some stochastic Fredholm integral equation contains as aknown function, the sine wave function
Background: Neonatal period is a very vulnerable period of life due to many problems, In spite of advances in perinatal and neonatal care still, the mortality rate of neonate high especially in developing country The World Health Organization estimates that globally four million neonatal deaths per year, Developing countries account for around 99% of the neonatal mortality in the world, In Iraq. Neonatal mortality rate about 19 per 1000 live births which represent 56% of child death below 5 years age in 2012. The hospital in the study represents the larger pediatric hospital in Iraq. It contains 400 children's beds and 24 neonatal incubators.
Aims of the study: are to determine the institutional
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This presented study is to make comparison of cross sections to produce 71As, 72As, 73As and 74As via different reactions with particle incident energy up to 60 MeV of alpha 100 MeV of proton as a part of systematic studies on particle-induced activations on enriched Ge, Ga, Rb and Nb targets and neutron capture. Theoretical calculation of production yield, and suggestion of optimum reaction to produce 71As, 72As, 73As and 74As, based on the main published and approved experimental results of excitation functions were calculated.
The purpose of this study was to evaluate the anesthetic effectiveness of a buccal infiltration technique combined with local massage (using 2% lidocaine) in the extraction of mandibular premolars to be utilized as an alternative to the conventional inferior alveolar nerve block.
Patients eligible included any subject with a clinical indication for tooth extraction of the mandibular 1st or 2nd premolars. All patients were anesthetized buccally by local infiltration technique followed by an external pressure applied for 1 min directly over the injection area. In each case, another local
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A simile is a figure of speech that draws resemblance with the help of the words such as (like) or any other closer in meaning word. The present paper deals with the theme of a simile in the poetry of Khwaju Kermani, a truly great Persian poet.
Besides being a great poet, Khwaju Kermani was also a fine professor of sciences. He was, also, known by his ghazals in which he imitated and was influenced by two of the most immense poets (Saadi) and (Hakim Sanai).
The search for knowledge, the pursue of studies and interpretation are among the main themes of Khwaju Kermani’s poetry. He uses ghazals to express love and longing in a mystical manner.
The present paper discusses the poet’s life, ethics and works.&n
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