The article describes a study on the role of vitamin C as a protective agent for the teeth, gum, and implants using quantum chemical calculations and polarization tests. The Density Functional Theory (DFT) at 6-311G (d, p) basis set is used to estimate the ability of vitamin C to inhibit the corrosion of the abovementioned parts. The experimental study was performed in a at human body media simulator (Hank’s balanced salt solution) at a temperature of 37°C. The compound was optimized for its ground state, physical properties, and corrosion parameters. Further, HOMO, LUMO, energy gap, dipole moment, and other parameters were used to predict the inhibitor’s efficiency. Gaussian 09, UCA-FUKUI, MGL tools, DSV, and LigPlus software was used. According to electron density, Electrostatic Surface (ESP), Total Electron Density (TED), FUKUI function, and dual descriptor were used to show the active sites of adsorption. Also, docking studies were applied to predict the effect of vitamin C on A. ferrooxidans bacteria, which causes eroding the implants. The Ti6Al4V alloy was tested at three concentrations of the VC inhibitor using the polarization method. A concentration of 55 mg/L is the best in terms of inhibitor efficiency (99.62%).
As population growth increases the demand for crops increases and their quality improves, and it becomes necessary to find innovative and modern solutions to enhance production. In this context, artificial intelligence plays a pivotal role in developing new technologies to improve crop sorting and increase agricultural yields. The present review discusses the main differences between manual and mechanical potato harvesting, explaining the advantages and disadvantages of each method. Manual harvesting is highlighted as a traditional method that allows for greater precision in handling the crop, but it requires more time and effort. In contrast, mechanical harvesting provides greater efficiency and speed in the process, but it may damage some
... Show MoreSince the beginning of the second decade of the twenty-first century, Saudi Arabia tried to pursue an open foreign policy towards many countries in the Horn of Africa, especially with Ethiopia and Somalia, due to the geostrategic qualities that these two countries possess.Despite the development of Saudi foreign policy towards Ethiopia and Somalia, it was soon affected by the tension after the events that the Gulf states went through, that is, the Qatari crisis with Saudi Arabia,especially after most of the countries of the Horn of Africa adhered to a policy of neutrality towards the Gulf-Gulf crisis.
Thus it is expected that despite the geographical proximity and the historical, economic and political relations between Saudi Ara
... Show MoreIn the present study twenty samples of human urine were taken
from healthy male and female with different of: ages, occupation and
place of residence. These samples were collected from the hospital to
measure the concentration of radon gas in human urine by using one
of solid state nuclear track detectors LR-115.
The results obtained of the concentrations of radon in healthy human
urine are varying from 2.12×10-3 Bq.l-1 to 4.42×10-3 Bq.l-1 and
these values are less than the allowed limits 12.3×10-3 Bq.l-1.
The aim of this research is to identify the role of strategic agility achieving organizational excellence in one of the formations of the Ministry of Municipalities (Dhi Qar Sewage Directorate), as important service organizations that have a key role in serving and developing the society which faced many administrative challenges and issues and as a result of the changes in the environment is continuing and accelerating, so the adoption of modern administrative concepts such as strategic Agility and knowledge of their role in achieving organizational excellence can help them in facing these changes and achieve what they aspire to. In order to achieve research objectives, two main hypotheses have been formulated. The first hypothe
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Background: Osteoporosis is a systemic skeletal disorder that has an impact on general health, dental health and salivary composition. The mineralization of teeth happens simultaneously with that of the skeleton, but if mineral metabolism is disrupted, tooth failures will resemble those that affect bone tissue. Vitamin D plays a key role in bone and tooth mineralization.
Objective: to evaluate the impact of osteoporosis on teeth decay in relation to salivary vitamin D among menopause in Baghdad city.
Subjects and Methods: This study was cross sectional study. The study group consists of
... Show MoreReducing global warming potential (GWP) of refrigerants is needed to the decrease of ozone-depleting of refrigeration systems leakages. Refrigerant R1234yf is now used to substitute R134a inside mobile air conditioning systems. Thermodynamic properties of R1234yf are similar to R134a. Also, it has a very low GWP of 4, compared to 1430 for R134a, making it a proper choice for future automobile refrigerants. The purpose of this research is to represent the main operating and performance differences between R1234yf and R134a. Experimental analysis was carried out on the automotive air conditioning system (AACS) with 3 kW nominal capacity, to test and compare the performance of R134a with R1234yf. Experiments were accomplish
... Show MoreThe current research aims to verify the role of strategic intelligence as an explanatory variable in organizational success as a respondent variable in the colleges of the University of Fallujah, the research community. (Dean, Associate Dean, Section Head, Division Officer, Unit Officer), The researcher used the questionnaire as the main tool to collect data that included (50) items, in addition to using personal interviews and field observations as aids in data collection. The researcher relied on statistical programs (SPSS V.25; Excel V (16) In the treatment and analysis of data through the use of the most appropriate statistical methods (arithmetic mean, standard deviation, difference coefficient, determinatio
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Photorefractive keratectomy (PRK) is the refractive technique that began with a physical scraping of the epithelial layer of cornea subsequent by laser treatment. Post this procedure to about 48 hours the removed epithelial layer regenerated to protect the eye again. The regeneration process (called re-epithelization) started from the limbus of the cornea toward the central part of it. The re-epithelization mechanism consists of a change in cell density (mitosis) and cell concentration (migration) with a velocity in two directions: radial and tangential. In the present study, an estimation for both radial (responsible for the overlapped layers toward the outward direction of the cornea) and tangential comp
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