Background: For decades, the use of naturally accessible materials in treating human disease has been widespread. The goal of this study was to determine the anti-fungal effectiveness /of the lemongrass essential oil (LGEO) versus Candida albicans (C. albicans) adhesion to polymethylmethacrylate (PMMA) materials. Material and methods: LGEO's anti-fungal activity was tested against C. albicans adhesion using the following concentration of LGEO in PMMA monomer (2.5 vol. %, 5 vol. % LGEO) selected from the pilot study as the best two effective concentrations. A total of 40 specimens were fabricated for the candida adherence test and were subdivided into four equal groups: negative control 0 vol. % addition, experimental with 2.5 vol. % and 5 vol. % of LGEO addition and positive control with 1.4 wt. % nystatin addition. The sterile PMMA specimens were incubated at room temperature for 1 hr in sterile tubes with a sabouraud dextrose broth (SDA) in which a small amount of the yeast was isolated and suspended; under the inverted light microscope, the examination was done. The data were evaluated using a one-way ANOVA test, which showed a significant result at p< 0.05. Results: The findings of the C. albicans adherence test exposed a considerable reduction in the number of C. albicans cells adhering to PMMA after adding 2.5 vol. % and 5 vol. % LGEO compared to specimens from the negative control and positive control groups at p< 0.05. Conclusion: Adding LGEO into a heat-cure acrylic material can result in a denture base material with anti-fungal properties versus C. albicans microorganisms. The experimental group 5 vol. % LGEO additive showed the best anti-fungal activity
The challenge to incorporate usability evaluation values and practices into agile development process is not only persisting but also systemic. Notable contributions of researchers have attempted to isolate and close the gaps between both fields, with the aim of developing usable software. Due to the current absence of a reference model that specifies where and how usability activities need to be considered in the agile development process. This paper proposes a model for identifying appropriate usability evaluation methods alongside the agile development process. By using this model, the development team can apply usability evaluations at the right time at the right place to get the necessary feedback from the end-user. Verificatio
... Show MoreThe objective of present study was to investigate the effect of using mixture volaticle oil of rosmarinus and nigella sativa to improve some of the meat quality characteristics, physical and limited storage time of minced cold poultry meat. Duplex volaticle oil was added at 0.025, 0.050 and 0.075 g/kg to minced poultry meat, these treatments were stored individually for 0 , 4 and 7 days at 4-7C0. After making several chemical, physical and oxidation indicators, the following results were obtained:
The process of adding volaticle oil to minced poultry meat led to significant increase (P<0.01)in moisture, prot
... Show MoreThe work was carried out in two stages. The first stage concerned
with study of silicon carbide (SiC) ratio (1.5, 2.5, 3.5, and 4.5 wt%)
effect on the Thermal conductivity of polyvinyl chloride (PVC); and
the second stage concerned with the UV – weatherizing (25, 50, and
75 hr), thermal aging (40, 50, and 60 °C), and rain- weatherizing (1,
2.5, and 4 hr) effect on the samples involved. Thermal conductivity
results proved that there was slight increase in thermal conductivity
by (SiC) loading; it increased from 0.17 W/m.K for PVC to 0.19
W/m.K for 4.5% SiC/PVC; where as it was systematically decreased
by UV- weatherizing, thermal aging, and rain- weatherizing. This
property is in a good agreement with gene
This study is a complementary one to an extended series of research work that aims to produce a thermodynamiclly stable asphalt –sulfur blend. Asphalt was physically modified wiht different percentages of asphaltenes , oxidized asphaltenes and then mixed with sulfur as an attempt to obtaine a stable compatible asphalt-sulfur blend. The homogeneneity of asphalt-asphaltenes[oxidized asphaltenes]-sulfur blends were studied microscopically and the results are prsented as photomicrographs. Generally more stable and compatible asphalt-sulfur blends were obtained by this treatment.
This paper presents the results of experimental investigation carried out on concrete model piles to study the behaviour of defective piles. This was achieved by employing non-destructive tests using ultrasonic waves. It was found that the reduction in pile stiffness factor is found to be about (26%) when the defect ratio increased from (5%) to (15%). The modulus of elasticity reduction factor as well as the dynamic modulus of elasticity reduction factor increase with the defect ratio
Nitinol (NiTi) is used in many medical applications, including hard tissue replacements, because of its suitable characteristics, including a close elastic modulus to that of bones. Due to the great importance of the mechanical properties of this material in tissue replacements, this work aims to study the hysteresis response in an attempt to explore the ability of the material to remember its previous mechanical state in addition to its ability to withstand stress and to obtain the optimal dimensions and specifications for the manufacturer of NiTi actuators. Stress-strain examination is done in a computational way using a mutable Lagoudas MATLAB code for various coil radii, environment temperatures, and coil lengths. The computational m
... Show MoreAn experimental and theoretical works were carried out to model the wire condenser in the domestic refrigerator by calculating the heat transfer coefficient and pressure drop and finding the optimum performance. The two methods were used for calculation, zone method, and an integral method. The work was conducted by using two wire condensers with equal length but different in tube diameters, two refrigerants, R-134a and R-600a, and two different compressors matching the refrigerant type. In the experimental work, the optimum charge was found for the refrigerator according to ASHRAE recommendation. Then, the tests were done at 32˚C ambient temperature in a closed room with dimension (2m*2m*3m). The results showed that th
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