Abstract: Background: Staphylococcus aureus is Gram-positive bacteria that lives as a normal flora in living organisms but can be pathogenic to humans. Although a relatively unspectacular, nonmotile coccoid bacterium, S. aureus is a dangerous human pathogen in both community-acquired and nosocomial infections. Due to the increasing emergence of new strains of this antibiotic-resistant bacteria, it has become essential to approach different methods to control this pathogen. One of these methods is the antimicrobial photodynamic inactivation process using a low-level laser, in this paper, the Photodynamic effects of Rose Bengal and LLLL on the virulence factors of S.aureus were evaluated. The aim of the study The present study aims to evaluate the Photodynamic effects on S. aureus using laser irradiation and Rose Bengal as an external photosensitizer. Methods: sixty samples from sputum were taken. Then ten isolated from these samples were chosen to be under the study, where RB was used at a concentatin of 100 μg/ml that is activated by diode laser (532 nm) with power density of 1 W/m2and exposure time (1, 2& 3) minute. Results: show that there is no effect on the inhibition of virulence factors except at the last minute, that is, the virulence factors decrease at the third minute only in the absence of a photosensitizer agent, while there is a direct effect of activated Rose Bengal on S. aureus isolated from the sputum of Iraqi patients with pneumonia, where all times of exposure of (RB + 532 nm) were effect on the virulence factors by inhibiting it. Conclusions: show that the diode laser of 532 nm has no effect on the virulence factor of S. aureus isolated from sputum except at the third minute, while RB activated by diode laser (532 nm) have an effective action on all virulence factors of S. aureus isolated from sputum at all times of exposure, accordingly, it was concluded that when using a laser diode alone, the bacterial viability decreases at the third minute only, While when using Rose Bengal activated by a diode laser, the viability of bacteria is reduced at all times of exposure.
The catalytic cracking of three feeds of extract lubricating oil, that produced as a by-product from the process of furfural extraction of lubricating oil base stock in AL-Dura refinery at different operating condition, were carried out at a fixed bed laboratory reactor. The initial boiling point for these feeds was 140 ºC for sample (1), 86 ºC for sample (2) and 80 ºC for sample (3). The catalytic cracking processes were carried out at temperature range 325-400 ºC and initially at atmospheric pressure after 30 minutes over 9.88 % HY-zeolite catalyst load. The comparison between the conversion at different operating conditions of catalytic cracking processes indicates that a high yield was obtained at 375°C, according to gasoline pr
... Show MoreIn this work, the copper metal was treated using Nd:YAG laser with energy 1Joul to enhance corrosion resistance and improve surface properties. The copper metal has many applications in industry as well as water, oil and gas pipes. The same conditions, (laser power density, scan speed, distance between paths, medium gas-air) were applied in the laser surface treatment, After laser treatment, the samples microstructures were investigated using optical microscope (OM) to examine micro structural changes due to laser irradiation. Specimen surfaces were investigated using atomic force microscopy (AFM), X-ray diffraction (XRD), macro hardness, and corrosion test before and after laser treatment to
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Background: Polyetheretherketone (PEEK) is a promising implant material due to its superior biomechanical strength. However, due to its hydrophobic nature and lack of cellular adhesion properties, it has poor integration with bone tissue. Methods: A fractional CO2 laser was used with various parameters for surface texturing of PEEK substrate to enhance its surface properties. An optical microscope and field-emission scanning electron microscope (FESEM) were used to examine the surface morphology of untextured and laser-textured samples. Energy dispersive X-ray spectroscopy (EDX) was performed to determine the effect of the laser on the microstructure of PEEK. Surface microroughness, atomic force microscopy (AFM), and wettability were invest
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Advancements in horizontal drilling technologies are utilized to develop unconventional resources, where reservoir temperatures and pressures are very high. However, the flocculation of bentonite in traditional fluids at high temperature and high pressure (HTHP) environments can lower cuttings transportation efficiency and even result in problems such as stuck pipe, decreased rate of penetration (ROP), accelerated bit wear, high torque, and drag on the drill string, and formation damage. The major purpose of the present research is to investigate the performance of low bentonite content water-based fluids for the hole cleaning operation in horizontal drilling processes. Low bentonite content water-based drilling fluids were formulated by re
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The research aims to identify the level of psychological burnout among the professors of Sana’a University in light of the armed conflicts in Yemen. The research sample consisted of (104) faculty members. A descriptive-analytical approach was adopted. The results of the research showed that university professors suffer from psychological burnout at a very high level in the overall score of the scale. There were no statistically significant differences in terms of gender, academic degree, teaching experience, marital status, number of family members, or salary. In light of the results, the researcher presented a number of relevant recommendations and suggestions.
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This study aims at identifying the activation of the role of feminine leaders in educational decision-making in educational administrations in the Northern Borders Province in light of the Kingdom's vision 2030. It also aims to identify what educational leadership is, to study the conceptual framework of the contemporary education decision-making process, and to examine the reality of the problems of feminine leaders in educational decision-making in the educational administrations in the Northern Borders. In addition, it tries to develop a proposed vision to activate the role of feminine leaders in educational decision-making in Educational Administrations in the Northern Borders Province in light of Vision 2030. To achieve the objectiv
... Show Moreالوصف New complexes of Cu (ll), Ni (II)„Co (II), and Zn (ll) with 2-amino-5-p-Flouro Phenyl 1, 3, 4-Thiadiazole have been synthesized. The products were isolated, studied and characterized by physical measurements, ie,(FT-IR)„UV-Vis and the melting points were determined. The new Schiff base (L) has been used to prepare some complexes. The prepared complexes were identified and their structural geometry were suggested