Background: Pit and fissure sealant have been considered an outstanding adjunct to oral health care in the decrease of occlusal caries onset and low progression. The aims of this in vitro study were to evaluate the marginal microleakage of three different types of fissure sealants (SDI, Tg and tetric N-flow) by time interval, one day and 45 days, in the presence or absence of bonding agent among maxillary and mandibular teeth. Materials and methods: Seventy two sound human maxillary and mandibular first premolar teeth were collected which were free from obvious carious lesions. The teeth were randomly divided into two main equal groups, group (1) and group (2), each group consists of (36) teeth involving equal numbers of maxillary and mandibular teeth. The first group incubated for one day, the second incubated for (45) days. Each group divided into two subgroup; one of them treated with bonding agent while the other without. Then each subgroup was treated with three different materials which were; Tg sealant (without fluoride) group (A), SDI sealant (containing fluoride) group (B) and Tetric N-flow (flowable composite) group (C). Each one consist of six teeth involving three maxillary and three mandibular. Then dye penetration tested by using methylene blue dye, then the teeth cleaned and sectioned by sectioning device and tested under microscope. Results, the results had shown that, group (C+) in both incubation periods have no microleakage (score 0), but there was an opposite effect when using bonding agent with sealant materials not containing filler particles that showed a significant increase in the microleakage rate as shown in groups (A+ and B+). The opposite effect was seen also when used sealant materials containing filler particles but without bonding agent that seen in group (C) during both incubation periods that showed significant increasing in microleakage rate. While the effect of fluoride was very clear in decreasing significantly the microleakage rate after (45) days of incubation in both groups that treated with and without bonding agent (groups B and B+). Concerning the anatomical variation, there were no significant changes in most groups regarding the microleakage rate. Conclusions: Results had shown that the microleakage can be prevented by using of flowable composite containing nanofillers that treated with bonding agent after etching of enamel with 35% phosphoric acid gel.
I n vitro rooting plantlets of three sugarcane genotypes(Co.j.64, Co.j.86 and Missan) were cultured in the field after exposed at different doses of gamma rays (1,2,3,4,) kr. Data of reduction percentage on vegetative growth, roots number, length per plant and their diameter were investigated. Results showed gradual reductions in number of shoots, length and diameter as according to increasing of gamma doses. The reduction percentage in shoot number, length were reached 57.86,70.36 % at 4 kr respectively which have mean number and length per plant reached (9.27 and 55.33 cm) as compared with the control treatment ,While 1 kr caused higher percent in diameter reached 9.69 % with mean of diameter per plant reached 2.57 cm. Mean time , Ge
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This study focuses on evaluating the suitability of three interpolation methods in terms of their accuracy at climate data for some provinces of south of Iraq. Two data sets of maximum and minimum temperature in February 2008 from nine meteorological stations located in the south of Iraq using three interpolation methods. ArcGIS is used to produce the spatially distributed temperature data by using IDW, ordinary kriging, and spline. Four statistical methods are applied to analyze the results obtained from three interpolation methods. These methods are RMSE, RMSE as a percentage of the mean, Model efficiency (E) and Bias, which showed that the ordinary krigingis the best for this data from other methods by the results that have b
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ملخص البحث باللغة الإنجليزية
The concept of the phenomenon of nuns: an analytical ideological study
Dr. Samia bint Yassin Al-Badri
Department of Islamic Doctrine & Contemporary Ideologies
College of Shariʿah & Islamic Studies
Qassim University
The study of concepts is one of the main pillars of doctrinal studies, in order to understand the formation of the concept, and to understand its contexts in religious sources, in order to be systematically criticized; So, this research came with the title:
The concept of the phenomenon of nuns, an analytical doctrinal study
The study concluded with resu
... Show MoreThe aim of this paper is to study the frames of Argument of normalization with Israel on the websites of the satellite channels directed in the Arabic language (Al-Alam and Al-Hurra Iraq) channels by analyzing the mechanisms of framing an Argument, The way in which we frame an issue largely determines how that issue will be understood and acted upon، The research adopted the survey method applied to the sites of(Al-
Alam and Al-Hurra) channels, at the period 13 Aug. - 12 Nov. 2020, which included (855) news items, (633) for Al-Alam channel website, and (222) for Alhurra Iraq channel website.
The most important results are: The two channels dependence on the Argument Directed, Al-Alam channel focuses on Islamic and Arab attitudes,
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The aim of this study was to propose and evaluate an eco-epidemiological model with Allee effect and nonlinear harvesting in predators. It was assumed that there is an SI-type of disease in prey, and only portion of the prey would be attacked by the predator due to the fleeing of the remainder of the prey to a safe area. It was also assumed that the predator consumed the prey according to modified Holling type-II functional response. All possible equilibrium points were determined, and the local and global stabilities were investigated. The possibility of occurrence of local bifurcation was also studied. Numerical simulation was used to further evaluate the global dynamics and the effects of varying parameters on the asymptotic behavior of
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Background: Hypertension is a chronic medical condition in which the blood pressure in the arteries is elevated, it's classified as either primary (essential) hypertension or secondary hypertension, and it increases the risk of ischemic heart disease, peripheral vascular disease and other cardiovascular diseases. Several classes of medications collectively referred to as antihypertensive drugs like beta blockers, calcium channel blockers, angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers, renin inhibitors and statins (HMG-CoA) reductase inhibitor. Statin medication may have some beneficial effects when subjects have dental plaque or signs of periodontitis as gingival bleeding. The purpose of this study were to as
... Show MoreThe effect of superficial gas velocity within the range 0.01-0.164 m/s on gas holdup (overall, riser and down comer), volumetric oxygen mass transfer coefficient, liquid circulation velocity was studied in an internal loop concentric tubes airlift reactor (working volume 45 liters). It was shown that as the usg increases the gas holdup and also the liquid circulation velocity increase. Also it was found that increasing superficial gas velocity lead to increase the interfacial area that increases the overall oxygen mass transfer coefficient. The hydrodynamic experimental results were modeled with the available equations in the literature. The predicted data gave an acceptable accuracy with the empirical data.
The final
... Show MoreThis paper aims to validate a proposed finite element model to be adopted in predicting displacement and soil stresses of a piled-raft foundation. The proposed model adopts the solid element to simulate the raft, piles, and soil mass. An explicit integration scheme has been used to simulate nonlinear static aspects of the piled-raft foundation and to avoid the computational difficulties associated with the implicit finite element analysis.
The validation process is based on comparing the results of the proposed finite element model with those of a scaled-down experimental work achieved by other researchers. Centrifuge apparatus has been used in the experimental work to generate the required stresses to simulate t
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