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.
Abstract
This study was to demonstrate the role-use planning scientific methods is disabled and little used in the planning and follow-up construction of vital projects in the province of Baghdad, including network planning methods, in order to find the optimal time to finish the project in light of the resources available and the budget set for it, in the current research has been used the most prominent network planning methods and two stylistic (CPM / PERT), was the application of the critical path method on standard-design school project (traditional) to draw Action Network according to confirmed times for the activities of the project and account his Crashing time , It was Pert technique applied to the project hemato
... Show MoreIt highlights the importance of construction projects because of its significant role in the development of society, including the buildings FEDE projects to their importance to raise the level of education through the conclusion of the special to implementation and the establishment of schools of contracts at the country level, which requires the completion of the project at less time and within the cost specified and the best quality and may highlight the importance of time on all the elements of what has an important role in setting up the project for various reasons may be the need for the use of schools as soon as possible, but the reality showed exceeded the completion of those schools could be up to 6 years and there are some cont
... Show MoreThe Early-Middle Miocene succession in Iraq is represented by the Serikagni, Euphrates and Dhiban formations, which deposited during the Early Miocene. The Jeribe and Fatha successions were deposited during Middle Miocene age. This study includes microfacies analysis, depositional environments, sequence stratigraphy and basin development of Early – middle Miocene in Hamrin and Ajeel oil fields and Mansuriyha Gas Field. The study area includes four boreholes in three oil fields located in central Iraq: Hamrin (Hr-2) and Ajeel (Aj-13, and 19) oil feilds, and Mansuriyha (Ms-2) Gas Field. Five facies associations were distinguished within the studied fields: deep marine, slop, platform-margin, open marine, restricted interior platform
... Show MoreBreast cancer (BC) is one of the most frequently observed malignancy in females worldwide. Today, tamoxifen (TAM) is considered as the highly effective therapy for treatment of breast tumors. Oxidative stress has implicated strongly in the pathophysiology of malignancies. This study aimed to investigate the changes in the levels of oxidants and antioxidants in patients with newly diagnosed and TAM-treated BC. Sixty newly diagnosed and 60 TAM-treated women with BC and 50 healthy volunteers were included in this study. Parameters including total oxidant capacity (TOC), total antioxidant capacity (TAC), and catalase (CAT) activity were determined before and after treatment with TAM. The serum levels of TOC and oxidative stress index (OSI) were
... Show MoreThis study was designed to investigate the hypoglycemic and hypolipidemic activity of aqueous green tea (GT) extract in normal and alloxan-induced diabetic rats. Forty adult male albino rats weighing 180-200 g were divided into four groups of 10 rats each: The first group was served as control; the second group was treated with GT (250 mg/kg b.w); the third group was affected by inducing experimental diabetes by intraperitonial injection of alloxan (150 mg/kg b.w); and the fourth group was affected by inducing diabetes and treated with GT (250 mg/kg b.w). Level of blood glucose and lipid profile [total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and ve
... Show Moreantimicrobial solutions against Coliforms, E. coli O157: H7, yeasts and molds were evaluated by agar well diffusion method. Chitosan (CH) exhibited best antimicrobial activity against the treated microorganisms at concentration of (5%) with contact time for 6hrs at refrigeration temperature (4ÚC), zones of inhibition for (GA) and (CH) for each solution alone ranging from (0 to 10 mm), chitosan solution (CH) exhibited both antibacterial and antifungal activities, Gum Arabic washing solution showed significant antibacterial activity (P < 0.05) against the microorganisms at concentration (15%), without inhibitory effect against E. coli O157:H7 at concentration (10%), in the current study the results confirmed that (15%) (w/v) of GA and 5%
... Show MoreBACKGROUND Multiple myeloma (MM) is a plasma cell disorder characterized by the infiltration of clonal plasma cells in the bone marrow and the detection of a monoclonal immunoglobulin in serum and/or urine. Renal failure, anemia, hypercalcemia, and the presence of bone lesions are the hallmarks of the disease. The study aimed to evaluate the clinical, hematological, radiological, and immunophenotypic features of MM patients and to identify prognostic factors influencing survival outcomes. This cohort study included 77 newly diagnosed, untreated MM patients. Their clinical presentation, laboratory data, imaging results, and the expression of flow cytometry markers were analyzed in correlation with the 1-year overall survival (OS). The mean a
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were determine the problem of current research to answer the question on the consciousness of the Ministry of Agriculture to adopt Staffing strategy and identify the shortcomings as the independent variable, represented by the three dimensions (recruitment , selection, placement) and its impact on high performance, as dependent variable is described in four dimensions (leadership, strategy, structure and processes, culture), in this research were Used analytical descriptive style . This research aims to identify the correlation and impact of Staffing strategy at high-performance in Ministry of Agriculture , To clarify the relationship between
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