Objectives: This study aimed to evaluate and compare the effect of plasma treatment versus conventional treatment on the micro shear bond strength (μSBS), surface roughness, and wettability of three different CAD/CAM materials. Materials and methods: Sixty cylindrical specimens (5 mm diameter ×3 mm height) were prepared from three different CAD/CAM materials: Group A: Zirconia, Group B: Lithium disilicate, and Group C: Resin nano-ceramic. Each group was subdivided into two subgroups according to surface treatment used: Subgroup I: Conventional treatment, zirconia was sandblasted with Al2O3, while lithium disilicate and resin nano-ceramic were etched with hydrofluoric acid. Subgroup II: Plasma treatment, the surface of each material was treated with a plasma device (PiezoBrush® PZ3 Handheld Device, Relyon Plasma, Regensburg, Germany). G-Multi PRIMER was applied, then self-adhesive cement (G-CEM ONE) was applied using a split mold (1 mm diameter ×3 mm height), and μSBS was tested in a universal testing machine. The surface roughness was measured using a profilometer. Nine additional specimens of each material for wettability test using an optical tensiometer. Statistical analysis: The data were analyzed using ANOVA and Bonferroni test at a level of significance of 0.05. Results: The highest mean of μSBS was recorded by AII (27.3 MPa), while the lowest was recorded by AI (17.9 MPa). One-way ANOVA test revealed a significant difference among groups. Bonferroni test showed each two subgroups significant difference except subgroups AI, CI and BII, CII, where there was a non-significant difference. For all CAD/CAM materials, conventional treatment increased the surface roughness compared to plasma treatment, while the contact angle decreased after plasma treatment. Conclusion: Plasma treatment increased the μSBS of resin cement to zirconia significantly while not significantly affecting the μSBS of resin nano-ceramic. Conventional treatment of lithium disilicate provided significantly higher μSBS than plasma treatment.
In this study, the effect of Nd: YAG laser on the activity of superoxide dismutase (SOD) and alcoholdehydrogenase (ADH) was investigated. The Saccharomyces cells were irradiated using 532nm Q-Switched Nd: YAG laser with (1Hz) frequency. Different fluences 11.3, 22.6 and 33.9mJ/cm2 and different number of pulses 15, 30 and 60 pulse were used. The irradiated cells were incubated in a liquid nutritive medium for 24 hours. After incubation, the cells were harvested and disrupted to extract the intracellular enzymes and their activities were assessed. In comparison with the control, the irradiated cells showed a significant increase in the activity and the specific activity of SOD at energy densities of 11.3 and 22.6mJ/cm2 at 30 and 60 pulses
... Show MoreThe house flies Musca domestica )Diptera:musidae) are the primary carrier of many pathogens such as cholera, typhoid, anthrax, and others. The use of chemical pesticides as a basic method of control leads to many problems at the environmental and health level. The use of safe alternatives to chemical pesticides has become an urgent necessity. The research aims to find biological alternatives that are environment-friendly and non-pathogenic to humans in controlling house flies through the possibility of extracting and diagnosing some secondary metabolites produced by the fungus Metarhizium anisopliae and testing their effects on the second larval stage of house flies using different treatment methods that include
... Show MoreThe present research was conducted to reduce the sulfur content of Iraqi heavy naphtha by adsorption using different metals oxides over Y-Zeolite. The Y-Zeolite was synthesized by a sol-gel technique. The average size of zeolite was 92.39 nm, surface area 558 m2/g, and pore volume 0.231 cm3/g. The metals of nickel, zinc, and copper were dispersed by an impregnation method to prepare Ni/HY, Zn/HY, Cu/HY, and Ni + Zn /HY catalysts for desulfurization. The adsorptive desulfurization was carried out in a batch mode at different operating conditions such as mixing time (10,15,30,60, and 600 min) and catalyst dosage (0.2,0.4,0.6,0.8,1, and 1.2 g). The most of the sulfur compounds were removed at 10 min for all catalyst ty
... Show MoreIn recent decades, the identification of faces with and without masks from visual data, such as video and still images, has become a captivating research subject. This is primarily due to the global spread of the Corona pandemic, which has altered the appearance of the world and necessitated the use of masks as a vital measure for epidemic prevention. Intellectual development based on artificial intelligence and computers plays a decisive role in the issue of epidemic safety, as the topic of facial recognition and identifying individuals who wear masks or not was most prominent in the introduction and in-depth education. This research proposes the creation of an advanced system capable of accurately identifying faces, both with and
... Show MoreIn this paper, an experimental study was conducted to enhance the thermal performance of a double-pass solar air heater (SAH) using phase change material (PCM) for thermal storage at climatic conditions of Baghdad city - Iraq. The double-pass solar air heater integrated with thermal storage system was manufactured and tested to ensure that the air heating reserved after the absence of the sun. The rectangular cavity filled with paraffin wax was used as a latent heat storage and incorporated into the lower channel of solar air heater. Experiments were carried out to evaluate the charging and discharging characteristics of two similar designed solar air collectors with and without using phase change material at a constant
... Show MoreThis study was aimed to extract the effective material from the dry nests of termites and detect its antibacterial activity against some pathogenic bacterial isolates and inhibit synthesis of its biofilm. Termites dry nests were collected and the effective material was extracted then the antibacterial activity was detected using the disc diffusion assay. Results were showed that the extract have antibacterial material from the Termites dry nests, this extract showed antibacterial activity against Gram positive bacteria (Staphylococcus aureus) at (21.5mm) and Gram negative bacteria ( Enterobacter sp. and Pseudomonas aeruginosa) at (26 mm and 20 mm) respectively by inhibiting their growth, as well as its effect on biofilm production o
... Show MoreThis paper aims at studying the illocutionary speech acts: direct and indirect to show the most dominant ones in a presidential speech delivered by the USA president. The speech is about the most critical health issue in the world, COVID-19 outbreak. A descriptive qualitative study was conducted by observing the first speech delivered by president Trump concerning coronavirus outbreak and surveying the illocutionary acts: directive, declarative, commissive, expressive, and representative. Searle's (1985) classification of illocutionary speech acts is adopted in the analysis.
What are the main types of the illocutionary speech acts performed by Trump in his speech?; Why does
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