Background: Polymers are very rarely used in their form. These modifications are carried out in order to improve the properties of polymers.Recently silver have been used successfully as antimicrobial (medical and dental) biomaterials that can prevent caries and infection of implants Purposes: The aim of the present in vitro study is to evaluate the effect of addition of silver nitrate to acrylic resin in different concentrationsthrough several tests part of these are: The effect of this additive on impact strength, transverse strength, and tensile strength of AgNO3 – loaded resin, and to assess any effect of addition of silver nitrate on coloration of acrylic resin. Materials and methods: Different concentrations of silver nitrate (9.375, 15, 30, 60, 120, 150, 300, 600 and 900 ppm) were prepared from stock solution of 1000 ppm silver nitrate. The specimens were prepared in accordance with the manufacturer's instructions and the tested silver nitrate solution was added to the acrylic resin powder and monomer in a fixed volume (0.2ml). Controls devoid of silver nitrate were included. Results: Fourier transform infra-red confirmed that there was no chemical bond between the Poly methyl methacrylate and silver nitrate. There was insignificant increasing (P=0.05) in impact strength observed when compared with control group. In transverse strength test, significant reduction was show (P<0.001). While for tensile strength there was insignificant reduction with 9.375(P=0.05NS) and 15(P=0.42NS) ppm silver nitrate. However, it was significant above 15 ppm (P<0.001). Darkening of silver nitrate -loaded resins were shown to be started with concentration of silver nitrateof 300 ppm and above. Conclusions: The additions of silver nitrate to acrylic resins yield good color stability and mechanical properties, depending on the concentration of silver nitrate.
In cooling water systems, cooling towers play a critical role in removing heat from the water. Cooling water systems are commonly used in industry to dispose the waste heat. An upward spray cooling water systems was especially designed and investigated in this work. The effect of two nanofluids (Al2O3/ water, black carbon /water) on velocity and temperature distributions along reverse spray cooling tower at various concentrations (0.02, 0.08, 0.1, 0.15, and 0.2 wt.%) were investigated, beside the effect of the inlet water temperature (35 ,40, and 45 ͦ C) and water to air flow ratio (L/G) of 0.5, 0.75, and 1. The best thermal performance was found when the working solution contained 0.1 wt.% for each of Al2
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Production and characterization of methionine γ- lyase from Pseudomonas putida and its effect on cancer cell lines
Introduction and Aim: Cancers are a complex group of genetic illnesses that develop through multistep, mutagenic processes which can invade or spread throughout the body. Recent advances in cancer treatment involve oncolytic viruses to infect and destroy cancer cells. The Newcastle disease virus (NDV), an oncolytic virus has shown to have anti-cancer effects either directly by lysing cancer cells or indirectly by activating the immune system. The green fluorescent protein (GFP) has been widely used in studying the anti-tumor activity of oncolytic viruses. This study aimed to study the anticancer effect of a recombinant rNDV-GFP clone on NCI-H727 lung carcinoma cell line in vitro. Materials and Methods: The GFP gene was inserted t
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The problem of the research lies in special motor abilities training programs like the balance that positively affect coordination between the nervous system and muscles. These training programs did not get enough attention from athletes especially young athletes; their training was restricted to physical abilities like strength, speed, and endurance instead. The research aimed at designing an apparatus for developing athletes’ balance in national centers for gifted/ ministry of youth and sport so as to provide a measurement for coached in this field. The results showed that the designed apparatus have a positive effect on developing the subjects’ balance in boxing and basketball athletes.
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t-Self-Compacting Concrete (SCC) reduces environmental noise and has more workability. This research presents an investigation of the behavior of SCC under mechanical loading (impact loading). Two types of cement have been used to produce SCC mixtures, Ordinary Portland Cement (OPC) and Portland Limestone Cement (PLC), which reduces the emission of carbon dioxide during the manufacturing process. The mixes were reinforced with Carbon Fiber Reinforced Polymer (CFRP) which is usually used to improve the seismic performance of masonry walls, to replace lost steel reinforcements, or to increase column strength and ductility. Workability tests were carried out for fresh SCC. Prepared concrete slabs of 500×500×50mm were tested for lo
... Show MoreThe research aims to study the effect of knowledge upgrade on business continuity in private colleges and universities in Baghdad. The research problem is summarized in the main question (were the academic leaders able to employ knowledge upgrading to enhance business continuity). The most important of this sector were the universities and the private college in the city of Baghdad as a field for this research, the researchers conducted a field visit to (10) universities or private colleges, the research sample consisted of (177) individuals from the deans of colleges and their assistants, as well as heads of scientific and administrative departments. The data was analyzed and the hypotheses were tested using the appropriate statistical
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A total of 60 cotton swabs are collected from patients suffering from burn wound and surgical site infections admitted to Baghdad Teaching Hospital and Burn Specialist Hospital in Baghdad city during 9/2013 to 11/2013. All cotton swabs are cultured initially on blood agar and MacConkey agar and subjected for standard bacteriological procedures for bacteriological diagnosis. Twenty samples out of sixty are identified as Pseudomonas aeruginosa by conventional methods. The results of antibiotic susceptibility test illustrate that the antibiotics resistance rate of Pseudomonas aeruginosa isolates is as follows:100% (2020) for ceftriaxone, cefepime and carbencillin, 70% (14/20) for amikacin, 65%(13/20) for tobramycin, ceftazidim and gentamycin,
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The purpose of this study was to investigate the effect of six thinking hats on creative thinking among 10th grade female students in Tulkarm district. The sample comprises two sections of 10th grade female students (n=80) in Adawiya secondary School, The two sections were divided into two groups; one as an experimental group which works with six thinking hats, and the second as control group that learns traditionally. Creative thinking exam was used to measure the creative thinking with reliability (0.88).
The results of the study have shown the following:
There were statistically significant differences at (α ≤ 0.05) in the creative thinking among 10th grade female student
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