Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; such methods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasive action. This study was done to assess the effect of three polishing systems on surface texture of new anterior composites after storage in artificial saliva. Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and 3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for one month and then samples were divided into four groups according to surface treatment: Group A (control group):10 specimens received no surface polish and were subdivided into A1 (Giomer) and A2 (Tetric®N-Ceram). Group B: 10 specimens received polishing with Air polishing devise (APD) and were subdivided into B1 (Giomer) and B2 (Tetric®N-Ceram). Group C: 10 specimens received polishing with pumice and brush and were subdivided into C1 (Giomer) and C2 (Tetric®N-Ceram). Group D: 10 specimens were polished with pumice and rubber cup and were subdivided into D1 (Giomer) and D2 (Tetric®N-Ceram). Testing was done by means of profilometer and statistically analyzed using analysis of variance test (ANOVA), LSD and student t-test. Also samples were photographed by special orthoplane camera using light polarizing microscope. Results: The results showed a highly statistical significant difference in surface roughness among Giomer subgroups P<0.05. Also there was a highly significant difference P<0.05 when comparing Tetric subgroups according to type of surface treatment. Furthermore there was non-significant difference P>0.05 between groups according to the type of restorative material used. Conclusion: The use of prophylactic surface treatment significantly increased Giomer and Tetric ceram surface roughness and the use of rotating brush has shown the roughest surface among all other types of prophylactic protocols also Giomer had shown more surface roughness than Tetric ceram although the difference was not significant.
This paper presents the non-linear finite element method to study the behavior of four reinforced rectangular concrete MD beams with web circular openings tested under two-point load. The numerical finite elements methods have been used in a much more practical way to achieve approximate solutions for more complex problems. The ABAQUS /CAE is chosen to explore the behavior of MD beams. This paper also studies, the effect of both size and shape of the circular apertures of MD beams. The strengthening technique that used in this paper is externally strengthening using CFRP around the opening in the MD beams. The numerical results were compared to the experimental results in terms of ultimate load failure and displace
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This study aimed to obtain an isolate of a mold that has well characteristic for production of citric acid from raw materials available locally by solid-state fermentation and determination of the optimum conditions for production .Fourteen mold isolates producing acid were obtained from different sources, involved decayed fruits and soils. These isolates were subjected to initial qualitative screening followed by secondary quantitative screening In secondary screening a method combined between the submerged fermentation and solid-state fermentation was followed using a piece of sponge saturated by nutrients required for growth and production of acid. It was found that the isolate of A7 was the highest producer for citric acid tha
... Show MoreA case of systemic lupus erythematosus like induced by carbamazepine therapy in a 27 year old female patient with left sided trigeminal neuralgia had been recorded, 9 years from starting carbamazepine therapy. The patient condition improved clinically 3 days after withdrawal of
carbamazepine , the titer of antinuclear antibodies dropped from 1/640 to 1/80 after 3 weeks, and disappear completely after 6 months follow up.
This paper presents a vibration suppression control design of cantilever beam using two piezoelectric patches. One patch was used as an actuator element, while the other was used as a sensor. The controller design was designed via the balance realization reduction method to elect the reduced order model that is most controllable and observable. the sliding mode observer was designed to estimate six states from the reduced order model but three states are only used in the control law. Estimating a number of states larger than that used is in order to increase the estimation accuracy. Moreover, the state estimation error is proved bounded. An optimal LQR controller is designed then using the estimated states with the slid
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Field trial was conducted during the growing season of 2011-2012 at the Research
Field, Department of Biology, College of Science, Baghdad University to test the
performance of wheat cv Rabyaa, Latifiya, Al-Iraq, Tummose 2, Abu-Graib 3, IPA
99 and Sham 6 grown under different soil water deficit stresses. Several agronomic
and physiological traits and yield and yield components of the test cultivars were
determined. The experiment was conducted in split plot design with five replications
for each treatment. The cultivars were kept in the sub plot while water stress
treatment was assigned as main plot. Water stress was applied by irrigated the plots
to the soil field capacity (FC) then withheld next irrigation until
Accurate calculation of transient overvoltages and dielectric stresses from fast-front excitations is required to obtain an optimal dielectric design of power components subjected to these conditions, which are commonly due to switching and lightning, as well as utilization of power-electronic devices. Toroidal transformers are generally used at the low voltage level. However, recent investigations and developments have explored their use at the medium voltage level. This paper analyzes the model-based improvement of the insulation design of medium voltage toroidal transformers. Lumped and distributed parameter models are used and compared to predict the transient response and dielectric stress along the transformer winding. The parameters
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This research focuses on the removal and adsorption of Fe (III) ion using a low cost commercial polyacrylic acid hydrogel beads as adsorbent. The effects of time, initial concentration and pH on the metal ion adsorption capacity were investigated. The regeneration of the hydrogel bead and recovery of the metal ion adsorbed were study. The adsorption isotherm models were applied on experimental data and it is shown that the Langmuir model was the best one for Fe (III) ion removal. The maximum capacity was calculated. First-order and second- order kinetic models were used and it is shown that the experimental data was in reliable compliance with the first- order model with R2 value of (0.9935, 0.9011, 0.9695, 0.9912) for all concentrations
... Show MoreTillage appearance device is mechanical, electric-electronic design, getting Patent from the Central Organization for Standardization and Quality Control – Industrial Property Department - Ministry of Planning – The Republic of IRAQ under number Patent 3876 in 20 / 4 / 2014, calculates the number of clods per area by Tillage appearance device, This is done through the generation electrical impulses are sent to the controlled accurate calculates number clods required space and shows the result on the screen in order to see the tillage view per area. Three factor used in these experiment, first factor represents forward speed of tractor three levels (3.5, 4.5, and 5.5 km/h), second factor represent soil moisture content at two levels (14
... Show MoreAbstract :H.pylori is an important cause of gastric duodenal disease, including gastric ulcers, Mucosa-associated lymphoid tissue (MALT), and gastric carcinoma. biosensors are becoming the most extensively studied discipline because the easy, rapid, low-cost, highly sensitive, and highly selective biosensors contribute to advances in next-generation medicines such as individualized medicine and ultrasensitive point-of-care detection of markers for diseases. Five of ten patients diagnosed with H.pylori ranging in age from 15–85 participated in this research. who [gastritis, duodenitis, duodenal ulcer (DU), and peptic ulcer (PU)] Suspected H.pylori colonies w
... Show MoreBackground: To determine the DNA content in subfertile patients and to correlate it with seminal sperm concentration.
Design: Prospective observational study.
Setting: College of Medicine, Dept. of Physiological chemistry and Institute for embryo Research and infertility treatment-University of Baghdad.The study was conducted
through years 2004-2005.
Methods: A random sample of 61 subfertile male patients undergoing semen evaluation and aged from 20-45 years were studied. Semen samples were assessed for seminal sperm
concentration microscopically and were classified into 3 different groups according to count (million/ml).Then sperm D N A content (μg/ml) was estimated using a microchemical
spectropho