Background: Saliva is one of the most important etiological host factors in relation to dental caries. It affects the carious process by its organic and inorganic constituents; in addition to its physiological functions as (flow rate, pH and buffer capacity). The aims of this study were to determine the concentrations of major elements (calcium and phosphorus) and trace elements (ferrous iron, nickel, chromium and aluminum) in saliva among a group of adolescent girls, and to explore the relation of these elements, flow rate and pH with dental caries. Material & Methods: The study group consisted of 25 girls with an age of 13-15 years old. Dental caries was diagnosed by both clinical and radiographical examinations following the criteria of D1-4MFS index. Stimulated saliva was collected from patients between 9-11 Am under standarized conditions, and chemically analyzed to determine the concentration of calcium, nickel, chromium and aluminum by Atomic Absorption Spectrophotometer, while salivary phosphorus and ferrous iron were determined by using colorimetric method. The average salivary flow rate was measured from total volume, and salivary pH was determined using digital pH meter. All data were analyzed using SPSS version 19. Results: All elements measured in saliva in addition to P/Ca ratio recorded statistically non significant correlation with DMFS, except ferrous Fe ions which showed statistically significant correlation (r= 0.34, P=0.05). Salivary flow rate and pH correlated weakly and statistically not significant with DMFS There were weak and statistically not significant correlations between all elements measured in saliva and salivary flow rate and pH. Conclusions: It had been found that Fe, Ni, Al and Cr ions present in very small amounts in saliva in comparison to Ca and P ions. The presence of these elements in saliva may indicate their presence in food, water and air.
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Language plays a major role in all aspects of life. Communication is regarded as the most important of these aspects, as language is used on a daily basis by humanity either in written or spoken forms. Language is also regarded as the main factor of exchanging peoples’ cultures and traditions and in handing down these attributes from generation to generation. Thus, language is a fundamental element in identifying peoples’ ideologies and traditions in the past and the present. Despite these facts, the feminist linguists have objections to some of the language structures, demonstrating that language is gender biased to men. That is, language promotes patriarchal values. This pushed towards developing extensive studies to substantiate s
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Utilizing the Turbo C programming language, the atmospheric earth model is created from sea level to 86 km. This model has been used to determine atmospheric Earth parameters in this study. Analytical derivations of these parameters are made using the balancing forces theory and the hydrostatic equation. The effects of altitude on density, pressure, temperature, gravitational acceleration, sound speed, scale height, and molecular weight are examined. The mass of the atmosphere is equal to about 50% between sea level and 5.5 km. g is equal to 9.65 m/s2 at 50 km altitude, which is 9% lower than 9.8 m/s2 at sea level. However, at 86 km altitude, g is close to 9.51 m/s2, which is close to 15% smaller than 9.8 m/s2. These resu
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This paper discusses estimating the two scale parameters of Exponential-Rayleigh distribution for singly type one censored data which is one of the most important Rights censored data, using the maximum likelihood estimation method (MLEM) which is one of the most popular and widely used classic methods, based on an iterative procedure such as the Newton-Raphson to find estimated values for these two scale parameters by using real data for COVID-19 was taken from the Iraqi Ministry of Health and Environment, AL-Karkh General Hospital. The duration of the study was in the interval 4/5/2020 until 31/8/2020 equivalent to 120 days, where the number of patients who entered the (study) hospital with sample size is (n=785). The number o
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Copper electrodeposition by electrorefining process in acidic sulfate media contains 40 g/l of cupric ions and 160 g/l of sulfuric acid was achieved to study the influence of the operating parameters on cathode purity, surface morphology, deposition rate, current efficiency and power consumption. These operating parameters and there ranges are: current density 200, 300 and 400 A/m2, electrolyte temperature 35, 50 and 65 oC, electrodes spacing 15, 30 and 45 mm and electrolyte residence time 6, 4 and 2 h were utilized. XRF, SEM and EDX analyses were attained to clarify the properties of the produced cathode.
For modeling a photovoltaic module, it is necessary to calculate the basic parameters which control the current-voltage characteristic curves, that is not provided by the manufacturer. Generally, for mono crystalline silicon module, the shunt resistance is generally high, and it is neglected in this model. In this study, three methods are presented for four parameters model. Explicit simplified method based on an analytical solution, slope method based on manufacturer data, and iterative method based on a numerical resolution. The results obtained for these methods were compared with experimental measured data. The iterative method was more accurate than the other two methods but more complexity. The average deviation of
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