ABSTRACT Background: This study measured the effects of three parameters pH value, length of immersion and type of archwire on metal ions released from orthodontic appliances. Materials and Methods: Ninety maxillary halves simulated fixed orthodontic appliances that were immersed in artificial saliva of different pH values (6.75, 5 and 3.5) during 28 day period. Three types of archwires were used: stainless steel, nickel titanium and thermal activated nickel titanium. The quantity of nickel and chromium ions was determined with the use of atomic force spectrophotometer while iron ions by spectrophotometer. Each orthodontic set was weighted two times, before the ligation and immersion in the artificial saliva and after 28 days at the end of immersion period using analytic balance device. Results: The release different metal ions was observed: nickel (Ni), chromium (Cr) and iron (Fe)). Statistically analysis of variance (ANOVA) and t-test were used. Results showed that (1) the appliances released measurable quantities ofall ions examined; (2) the change in pH had a very strong effect on the release of ions; (3) the release of ions was dependent on wire composition, but it was not proportionalto the content of metal in the wire and (4) orthodontic samples showed decreases in the weight at the end of the study. Conclusion: Levels of released ions are sufficient to cause delayed allergic reactions. This must be taken into account when type of archwire is selected, especially in patients with hypersensitivityor compromised oral hygiene.
Nasiriya field is located about 38 Km to the north – west of Nasiriya city. Yammama, a giant lower cretaceous reservoir in Nasiriya field which is lithologically formed from limestone. Yammama mainly was divided into three main reservoir units YA, YB1, YB2 and YB3 and it is separated by impermeable layers of variable thickness. An accurate petro physical evolution of the reservoir is of great importance perform an excellent geological model so that four petro physical properties which are shale volume, porosity, water saturation and permeability was re-evaluated. The volume of shale was calculated using the density and neutron logs (VSH-DN) rather than using gamma ray log because of presence a uranium content in the formation that make
... Show MoreBackground : The kidneys may be injured in abdominal trauma, both blunt & penetrating. Renal trauma may manifest in a dramatic fashion for both the patient and the clinician. Objectives: To evaluate the incidence, management, morbidity &mortality of renal injury in blunt & penetrating abdominal trauma.
Results:The majority o f patients were males (35= 77.8%), the rest were females (10= 22.2%). The average age was 37 years (range= 18-56 years). The most common grades were grade1, grade2 and grade3 (40=88.9%), while 5 patients (11.1%) were grades 4 and 5.The most common associated injuries were liver, spleen, small & large bowels and diaphragm. The mortality was 20% (9 patients). The most common cause of death was multip
In The Bluest Eye (1970), the American-African writer, Toni Morrison explores how
Western standards of ideal beauty are created and propagated with and among the black
community. The novel not only portrays the lives of those whose dark skinned and Negroid
features blight their lives; it also shows how the standard of white beauty, when imposed on
black youth, can drastically damage one’s self-love and esteem which usually occurs when
beauty goes unrecognized. Morrison in this novel focuses on the damage that the black
women characters suffer through the construction of femininity in a racialised society where
whiteness is used as a standard of beauty.
Kurdish language multifunctional morphemes indicate the different functional morphological, syntactical, and semantic tasks of the morphemes. The present study discusses the multifunctional task of the Morpheme Le in Kurdish Language. The Morpheme Le has marginally been included in other studies, yet up to the present times, there has not been a research inclusively dedicated to thoroughly discuss and clarify its multifunctional aspects. The present study is divided into two chapters: Chapter one discusses the theoretical aspect of chapter two that is entirely concerned with the practical aspect of the morpheme Le. The first part of chapter one sheds light on the morphological aspect of the morpheme while part two discusses
... Show MoreIn The Bluest Eye (1970) , Toni Morrison addresses a timeless problem of white racial dominance in the United States and points to the impact it has on the life of black females growing up in the 1930's. Morrison in this novel explores how Western standards of ideal beauty are created and propagated with and among the black community. The novel not only portrays the lives of those whose dark skinned and negroid features blight their lives; it also shows how the standards of white beauty are imposed on black youth to cause a damage of one's self-love and esteem which usually occurs when beauty goes unrecognized
Adsorption of Acetone and 2-Butanone on Iraqi siliceouns rocks powder have been investigated. UV technique has been used to determine the adsorption isotherms. The results showed that the adsorption isotherms obeyed Freundlich adsorption equation. The results showed that the adsorption increases with increasing acidity of solutions. The adsorption was exothermic process, increasing temperature leads to decreasing adsorption. H, S, G were calculated
The contractual imbalance is perceived today by the majority of the doctrine as being one of the pitfalls to the execution of the contracts. As a result, most legislations grant judges the power to intervene to restore it. Granting the judge the power to complete the contract raises the question of the extent to which the judge can obtain such power. Is it an absolute authority that is not limited? If so, is it a broad discretion in which the judge operates in his conscience, or is it a power of limited scope by specific legal texts and conventions? This is what we will try to answer in this research.
In this study, stabilization of expansive soils using waste materials namely; Cement Kiln Dust (CKD), and waste plastic bottles (WPB) was experimentally investigated. Using CKD and WPB are exponentially increasing day by day, due to their capability to solve both environmental and geotechnical problems successfully. Expansive soils were collected from locations with a wide range of plasticity index (PI) (15 - 27) and liquid limit (LL) (35% - 64%). Stabilizer percentages were varied from 0% to 20%, and curing durations for CKD cases were 7 and 28 days. Results showed the best percentages of CKD and WPB are 12% of each one respectively. LL, plastic limit (PL), and swelling percent (SP) loss were observed, which are 46%, 55%, and 96% respec
... Show More