Background: To evaluate the effect of antierosive agents (10% Nano-Hydroxyapatite (NHA), 10% Casein Phophopeptide-Amorphous Calcium Phosphate (CPP-ACP), and combination of 10% NHA and 10% CPP-ACP) on loss of minerals from enamel surface of permanent teeth treated with antierosive agents when exposed to an acidic beverage and investigate the morphological changes of treated enamel surface after demineralization with cola based beverage under Scanning Electron Microscope (SEM). Materials and Methods: Sixty maxillary first premolars were randomly divided into four groups, 15 teeth for each group. Group I treated with 10% NHA, Group II treated with 10% CPP-ACP, Group III treated with 10% NHA and 10% CPP-ACP, and Group IV did not treat with any remineralizing agents. The teeth were immersed in the remineralizing solutions (10% NHA, 10% CPP-ACP, and combination of 10% NHA and 10% CPP-ACP) for 4 minutes twice daily for 28 days and then stored in the artificial saliva. The samples were immersed for 40 minutes in 20 ml Pepsi cola (PH=2.5). Atomic Absorption Spectrophotometer (AAS) was used to record the calcium and phosphorus concentrationsin Pepsi cola before and after demineralization with cola based beverage. SEM also usedto examine the morphological changes occurs in enamel surface of each group after demineralization with cola based beverage. Results: Statistically, there is a highly significant increase in calcium concentration in Pepsi cola (mg/dl) after demineralization with cola based beverage. Group I showed the lowest changes in calcium concentration values among the three studied groups. Group II was the next, which also showed lower changes in calcium concentration values, then group III while the highest changes were recorded in group IV. There is a highly significant reduction in phosphorus concentration in Pepsi cola (mg/dl) after demineralization with cola based beverage. Group I showed the lowest changes in phosphorus concentration values among the three studied groups. Group II was the next, which also showed lower changes in phosphorus concentration values, then group III while the highest changes were recorded in group IV. Statistically, a highly significant difference was showed in calcium and phosphorus concentrations between the four studied groups after demineralization with cola based beverage. Group IV has a highly significant difference in comparison to group I, group II, and group III. Conclusions: Both the remineralizing agents (NHA and CPP-ACP) were found to be effective in inhibiting the demineralization caused by cola based beverage.The combination of NHA and CPP-ACP had no synergistic effect on remineralization.
This study shows impoliteness as a form of face-threatening that can be intentionally caused by verbal threats in a particular setting. It investigates: what strategies and mitigators do Iraqi-Kurdish English as a foreign language (EFL) learners use in situations of threat responses? The present investigation paper aims to examine impoliteness strategies and mitigators by these learners when they respond to threatening situations in their context. Thus, it fills a gap in pragmatics literature by investigating the reactions to threats in an Iraqi-Kurdish EFL context. To this end, 50 participants have participated in this study. An open-ended questionnaire in the form of a Discourse Completion Task (DCT) is used to elicit responses fr
... Show MoreObjective The incidence of rhythm and conduction abnormalities during acute myocardial infarction may approaches 100%; most are seen during the pre-hospital and coronary care unit phases, leading to deleterious effect on morbidity and mortality, this study conducted to find important persistent dysrhythmia found during CCU admission of acute myocardial infarction patients.Method A retrospective observational study of 553 patients who were admitted to the Coronary Care Unit of Alkindy Teaching Hospital during Year 2011 with diagnosis of acute myocardial infarction, Information and data extracted from case sheets and associated 12 leads daily ECGsResults only 25% of our patients had dysrhythmia on examining the present 12 leads ECGs , the
... Show MoreThe goal of this research to identify a set of criteria that can be measured on the basis of which the effectiveness of the application of the Balanced Scorecard in the Jordanian Public Institutions in order to identify the basic requirements to ensure the application of balanced performance measures. The study population consisted of the staff of the Public Institution for Social Security - Irbid of directors of departments and heads of departments and administrative staff, was the use of a random sample of (50) an employee and the employee. The questionnaire was used as a tool to collect data, and as a result of subjecting these standards for the field test and the use of statistical analysis tools to the results of the study c
... Show MoreNAA Mustafa, University of Sulaimani, Ms. c Thesis, 2010 - Cited by 4
Objecte The study aims to test the effect of using the appropriate quantitative method of demand forecasting in improving the performance of supply chain of the aviation fuel product ( The study sample), One of the products of the Doura refinery (The study site), By testing a set of quantitative methods of demand forecasting using forecasting error measurements, and choosing the least faulty, most accurate and reliable method and adept it in the building chain.
Is the study of problem through a starting with the fol
... Show MoreThis study examined the correlation between binder-level fatigue properties and mixture-level cracking resistance in asphalt binders modified with five Nanomaterials (NMs): Nano-Silica (NS), Nano-Alumina (NA), and Nano-Titanium dioxide (NT) at 2%, 4%, and 6% as well as Nano-Zinc oxide (NZ) and Carbon Nanotubes (CNTs) at 1%, 2%, and 3%. Modified binders were subjected to Rolling Thin-Film Oven Test (RTFOT) and Pressure Aging Vessel (PAV) aging and tested at 25 °C using the Linear Amplitude Sweep (LAS) test to determine fatigue life (Nf) and the fatigue parameter G*.sin δ. The corresponding asphalt mixtures were evaluated using the IDEAL-CT test. The results indicated strong correlations between binder and mixture performance for
... Show MoreBased on previous research results that recognized the role of paternalistic leadership in promoting a positive work climate, this study explored the impact of a toxic work environment on the mental health and well-being of employees. We used the quantitative methodology to collect and analyze data. A sample of 108 participants from Iraqi internet service provider (ISPs) companies represented the purposive study sample. We targeted employees who experienced the COVID-19 pandemic. All data was collected through an electronic questionnaire (Google and Microsoft Forms). The research model was tested using structural equation modeling (SEM). The results showed a negative effect of the toxic workplace on the mental health of employees. T
... Show MoreAbstract
The research stems from the problem that focuses on a number of questions. They are as follows: What is the extent of interest in the topic of efficiency by the banks and their role in raising the efficiency of the banking business and its development? Is the banking efficiency used in Iraqi banks clear and specific for the Iraqi banking sector? How the banking sector efficiency is measured and what are the approaches adopted in determining the banking inputs and outputs? What is the level of efficiency in the research sample of the banks and what are the causes of its decline or rise in private banks individually and in the Iraqi banking sector in general?
The re
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