Background: Nanotechnology represents a new science that promises to provide a broad range of uses and improved technologies for biological and biomedical applications. One of the reasons behind the intense interest is that nanotechnology permits synthesis of materials that have structure is less than 100 nanometers. The present work revealed the effect of zinc oxide nanoparticles (ZnO NPs) on Streptococcus mutans of Human Saliva in comparison to de-ionized water. Materials and methods: Streptococcus mutans were isolated from saliva of forty eight volunteers of both sexes their age range between 18-22 years and then purified and diagnosed according to morphological characteristic and biochemical tests. Different concentrations of ZnO NPs were prepared from the stock solution; all the experiments were conducted in vitro. Disk diffusion method was used to study the sensitivity of Streptococcus mutans to different concentrations of zinc oxide nanoparticles in comparison to effect of de-ionized water. Results: Streptococcus mutans were sensitive to concentrations (0.05, 0.1, 0.5, 1, 3 and 5.8) mg / ml of the zinc oxide nanoparticles solution in comparison to de-ionized water, revealing a highly significant difference in all concentrations except for concentration (0.01) mg / ml which was showed no significant difference in comparison to de-ionized water. Conclusion: This study revealed that zinc oxide nanoparticles were effective against Streptococcus mutans.
The current research aims to identify the effect of the hands_on strategy on the life effectiveness skills of the first grade students in the government's daytime middle schools. The Umm al-Mu 'minin school was intentionally chosen to be the research sample of the second Rusafa Directorate for the academic year 2021-2022. Then, two divisions were randomly chosen for the first of the six divisions to represent the experimental group that is studying according to the strategy of the hands_on and the other the control group that is studying according to the usual method. The equivalence of the two research groups was verified by a set of variables. The two groups were found to be equivalent. As for the research tool, the life effectiveness sca
... Show MoreTook apple branches Genuine and Architecture tissue cultured in vitro 3 cm long and planted in the middle of food MS that contains different concentrations of inorganic salts and of Mntmat free growth and incubated Transplanter to study their effect on rooting Aalavra
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Indium oxide In2O3 thin films fabricated using thermal evaporation of indium metal in vacuum on a glass substrate at 25oC using array mask, after deposition the indium films have been subjected to thermal oxidation at temperature 400 °C for 1h. The results of prepared Indium oxide reveal the oxidation method as a strong effect on the morphology and optical properties of the samples as fabricated. The band gap (Eg) of In2O3 films at 400 °C is 2.7 eV. Then, SEM and XRD measurements are also used to investigate the morphology and structure of the indium oxide In2O3 thin films. The antimicrobial activity of indium oxide In2O3 thin films was assessed against gram-negative bacterium using inhibition zone of bacteria which improved higher ina
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The insurance companies are one of the organizations that rely mainly on human capital to underwriting to insurable risks because most of risks have many variables, so the aim of the research is to show the level of interest of the researched company in human capital, the reality of the underwriting policy in it, and the relationships of correlation and effect between them, and the approach has been used Analytical descriptive, as books, research and other related sources were used for the purpose of completing the theoretical side, on the practical side, a questionnaire was prepared, which represents the main tool for collecting data and distributed to a random sample of 64 people from underwriting managers and employees in spec
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Green biosynthesized selenium nanoparticles from
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The goals of endodontic preparation were to shape and clean the space of the root canal and remove microorganisms, affected dentin and pulp, the apical foramen and the canal curve should be protected from being transported during endodontic canal preparation. The aim of this study was to evaluate the curve straightening of curved root canals and apical transportation after preparation with four rotary systems. Forty mesial roots of the lower 1st molars teeth only the mesiobuccal canals were used, these roots were immersed into cold clear acrylic , the teeth roots divided into four groups according to rotary system used for preparation of the canals (ten roots for each group):. group I: ProTaper Next rotary system, group II: IRaCe Plus rotar
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There is various human biometrics used nowadays, one of the most important of these biometrics is the face. Many techniques have been suggested for face recognition, but they still face a variety of challenges for recognizing faces in images captured in the uncontrolled environment, and for real-life applications. Some of these challenges are pose variation, occlusion, facial expression, illumination, bad lighting, and image quality. New techniques are updating continuously. In this paper, the singular value decomposition is used to extract the features matrix for face recognition and classification. The input color image is converted into a grayscale image and then transformed into a local ternary pattern before splitting the image into
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