Background: Coated archwires have been introduced to improve esthetics during orthodontic treatment. Theaim of the present study was to evaluate and compare the load–deflection characteristics and force levels of six brands of coated nickel titanium orthodontic archwires using palatal and gingival deflection. Materials and methods: Ten round wires (0.016 inch) and ten rectangular wires (0.019x0.025 inch) were obtained from each of six brands (G&H, Opal, Ortho Technology, Dany, Hubit and Astar Companies). The load-deflection properties of these archwires were evaluated by the modified bending test usinga readymade dental arch model in both palatal and gingival directions at 37°C temperature using a universal material testing machine. Forces generated at maximum loading of 2mm and at unloading of 1.5mm were measured. Results: All the wires showed hysteresis and significant differences in their load deflection curves, but these differences were more evident in round wires than in rectangular wires where G&H wires showed the widest loading- unloading deflection curves. The maximum loading force of round wires in gingival deflection were higher than by palatal deflection. The force decline during unloading (plateau gap) ranged between 18 to 34% for round wires and 17 to 37% for rectangular wires. Conclusion: Coated epoxy wires (G&H, Opal, Astar and Ortho Technology) produced lower forces compared to polymer (Dany) and Teflon (Hubit) coated round and rectangular archwire.
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In the present research we the study the deposition of radioactive elements naturally and particularly radioactive radon gas in parts of the body of organisms which are of direct relevance to human life in the city of Baghdad as the samples which were collected from the bones and skin of some kinds of birds and chicken based on the principle that radioactive elements are concentrated always on the bones. We use of this as the exercise detector impact nuclear (CR-39), using the technology Cylindrical diffusion , the results indicated that the largest concentration of radon found in the bone bird Seagull tapered as it was (625 ± 37) Bq.cm-3, and less concentration of radon gas in the chicken bones of Al-kafeel as it was (105 ± 10) Bq.c
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Abstract
The aim of this paper is to model and optimize the fatigue life and hardness of medium carbon steel CK35 subjected to dynamic buckling. Different ranges of shot peening time (STP) and critical points of slenderness ratio which is between the long and intermediate columns, as input factors, were used to obtain their influences on the fatigue life and hardness, as main responses. Experimental measurements of shot peening time and buckling were taken and analyzed using (DESIGN EXPERT 8) experimental design software which was used for modeling and optimization purposes. Mathematical models of responses were obtained and analyzed by ANOVA variance to verify the adequacy of the models. The resul
... Show MoreA new series of Schiff bases compounds , containing an azomethine linkage was synthesized and expected to be biologically active .The structures of these compounds were identified by IR , Uv/vis spectra , melting points and followed by T.L.C.The biological activity of these compounds was studied
In this study, new heterocyclic compounds were synthesized through the cyclization reactions of o-phenylenediamine (1) with various organic reagents. Benzodiazepine derivatives (2-4) were obtained by reaction of (1) with ethylacetoacetate, malonic acid and acetyl acetone.Treatment of compound (1) with chloroacetamide, chloroacetic acid, p-bromophenacyl bromide and oxalic acid dihydrate afforded quinoxaline derivatives (5-8), respectively. Reaction of compound (1) with benzoic acid, piperonal, cyclohexanone and carbon disulfide resulted in the formation of compounds (9-12), respectively. Finally, reaction of compound (12) with chloroacetic acid in the presence of potassium hydroxide produced compound (13).
The present study was carried out to compare the physicochemical characteristics of eggs of guinea fowl, turkeys and domestic chickens outdoor reared in traditional farms in Baghdad, Iraq. A total of 166 fresh eggs; 32 eggs from guinea fowls (Numida meleagris), 44 eggs from turkeys (Meleagris gallopavo) and 90 eggs from domestic chickens; were collected. Egg weight, percentage of egg components, chemical composition (protein, lipids, and ash), and lipid profile were determined. Results revealed the significant differences in egg weight among studied birds. The average egg weights for guinea fowl, turkey, and indigenous chicken were 48.51 ± 0.72, 52.15 ± 0.74 and 61.24 ± 0.22 g, respectively. No significant differences were found in egg c
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Synthesis, Characterization And Biological Evaluation of Schiff Base And Ligand Metal Complexes of Some Drug Substances
The experiment was carried out in College of Agricultural Engineering Sciences, University of Baghdad during November 1, 2019 to June 1, 2020. The experiment was designed according to a randomized complete block design. Each block contained 18 experimental units that included the three study factors. The first factor interaction between two inoculum densities and application methods, three levels control, treatment of seeds inoculation with 5g plant and treatment of seedlings inoculation whith 30g plant . The second factor was three -1 -1concentrations of spraying of kinetin 0, 75 and 150 mg L , and third factor include two levels of organic manure) and addition of fertilizer 2% of -1 the weight of the soil (O2). The results showed a signif
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