Background: Crown preparation of vital teeth involve the removal of a sound tooth structure, and when enamel removed this lead to exposed dentin with an   increase in the number of open dentinal tubules also the diameter of dentinal tubules will increase, furthermore lead to increase movement of fluids inside the tubules all that causes post preparation sensitivity. The aim of this study is to evaluate the effect of desensitizing by Er:Cr:YSGG laser on shear bond strength of prepared tooth and resin cement. Materials and methods: Thirty sound maxillary premolars, grouped into three groups(n=10). Group A is the control group, group B irradiated by Er:Cr:YSGG laser with (0.25 W, 20 Hz, 1

Influence of metal nanoparticles synthesized by microorganisms upon soil-borne microscopic fungus Aspergillus terreus K-8 was studied. It was established that the metal nanoparticles synthesized by microorganisms affect the enzymatic activity of the studied culture. Silver nanoparticles lead to a decrease in cellulase activity and completely suppress the amylase activity of the fungus, while copper nanoparticles completely inhibit the activity of both the cellulase complex and amylase. The obtained results imply that the large-scale use of silver and copper nanoparticles may disrupt biological processes in the soil and cause change in the physiological and biochemical state of soil-borne microorganisms as well.

The orientation allows the individual to develop the capacity to become aware of his personal characteristics and to develop them in order to choose his studies, his training and his professional activities, in all the conjunctures of his existence, with the joint concern for the collective future of solidarity and the fulfillment of one's personality and responsibility». (Danvers, 1992,p. 190). This advice states that: orientation is a process closely associated with education and formation. It becomes effective if the steps include broad information on education and trades, and focuses on the social development and moral construction of the individual. The objective of this survey is to show the influence of the orientation of the p

The food web is a crucial conceptual tool for understanding the dynamics of energy transfer in an ecosystem, as well as the feeding relationships among species within a community. It also reveals species interactions and community structure. As a result, an ecological food web system with two predators competing for prey while experiencing fear was developed and studied. The properties of the solution of the system were determined, and all potential equilibrium points were identified. The dynamic behavior in their immediate surroundings was examined both locally and globally. The system’s persistence demands were calculated, and all conceivable forms of local bifurcations were investigated. With the aid of MATLAB, a numerical simu

Sixty hyperthyroidism patients aged (20-45) years from different parts of Iraq , (20) from the North , (20) from Baghdad , (20) from the South of Iraq , and (20)control were tested for the presence of antithyroid peroxidase antibody(Tpo-Ab)and for Mg and Co levels in their sera.

The results revealed a significant increase in (Tpo-Ab) in all patients group from the different parts of Iraq compared to control , also a  significant increase in (Tpo-Ab) for  the group from  North compared to other parts.

A significant decrease in Mg and Co levels in sera of patients from all parts of Iraq compared to control values , while no significant differences among patient groups were notice

    The electronic properties (such as energy gap HOMO levels. LUMO levels, density of state and density of bonds in addition to spectroscopic properties like IR spectra, Raman spectra, force constant and reduced masses as a function of frequency) of coronene C₂₄ and reduced graphene oxide C₂₄O_X , where x=1-5, were studied.. The  methodology employed was  Density Functional Theory (DFT) with Hybrid function B3LYP and 6-311G** basis sets. The energy gap was calculated for C₂₄ to be 3.5 eV and for C₂₄O_x was from 0.89 to 1.6862 eV  for x=1-5 ,respectively.   These energy gaps values are comparable to the measured gap of Graphene (1-2.2 eV). The spectroscopic propertie