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 investigated. Results: There were significant increases in microroughness, nanoroughness, surface area ratio, and wettability after laser texturing with no change in the elemental composition. The best results were obtained by using 400 µs laser pulse duration with a dot separation distance of 0.2 mm and a 60° staggered dots pattern. Conclusions: Laser surface texturing of PEEK implant material by fractional CO2 laser is an easy and fast method of introducing patterned topographical features with no need for additional devices. With further investigations, this method of PEEK modification might have the potential to be used in the implant field.
The study area lies in the eastern part of Iraq, within Diyala and small parts of Salah Al-Din and Sulamanyah Governorates. The eastern boundary of the map represents Iraqi-Iranian International borders; it covers about 7001 Km2.The present study depends on two scenes of Thematic Mapper (TM5) data of Landsat and one scene of Multi-Spectral Scanner (MSS) data of Landsat, these data are subset and corrected within the ERDAS 9.2 software using UTM N38 projection. Normalized Difference Vegetation Index (NDVI) was adopted as practical tool for monitoring the surrounding area of Himreen Lake. The obtained result shows the distributions of NDVI for period 1976-1992 were positive pattern of (High vegetation density and Moderate vegetation densit
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The current research aims to identify the extent to which cognitive economics skills are included in the content of the chemistry textbook for the third intermediate grade, and the research sample was represented in the chemistry textbook for the third intermediate grade. A list of knowledge economy skills was prepared (6) main skills (basic skills, communication skills, thinking skills, work skills Group, information-gathering skill, behavioral skills (and (20) sub-skills) (reading, writing, operations, computer skills and employability, oral expression and written communication, dialogue, persuasion, influence and arousal, analysis, problem-solving, decision-making, suggestions and hypotheses and employing them. Controlling, directing
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The aim of the research is to introduce the international standards of the Supreme audit Institutions, as well as the role of these standards in achieving administrative reform and improving the performance of the Supreme audit Institutions and the performance of the economic units under its control.
In order to achieve the objectives of the research, a questionnaire was designed from two main axes that included a number of questions addressed to a number of officials and employees of the Supreme Audit Institutions and its affiliated bodies on the role of applying the international standards of the Supreme Audit Institutions in achieving administrative re
... Show MoreThe research aims to measure the efficiency of health services Quality in the province of Karbala, using the Data Envelopment analysis Models in ( 2006). According to these models the degree of efficiency ranging between zero and unity. We estimate Scale efficiency for two types of orientation direction, which are input and output oriented direction.
The results showed, according Input-oriented efficiency that the levels of Scale efficiency on average is ( 0.975), in the province of Karbala. While the index of Output-oriented efficiency on average is (o.946).
The flat-headed borer, Capnodis tenebrionis (Linnaeus, 1760) , dispersed extensively in various geographical regions; it is extremely harmful and a dire threat to most stone fruit cultivars, and once the larva enters under the host tree crown, the infested host tree will gradually dry and eventually die. In this study, specimens were collected from several sites in Erbil province, Kurdistan Region- Iraq; then the fully grown larvae were selected for morphological study. In addition, clarification of morphological consequential and implication for most diagnostic characters were studied in all dissected parts. Scanning electron microscope (SEM) was used to further analyze the hidden features of the selected characteristics;
... Show MoreThe present work presents design and implementation of an automated two-axis solar tracking system using local materials with minimum cost, light weight and reliable structure. The tracking system consists of two parts, mechanical units (fixed and moving parts) and control units (four LDR sensors and Arduino UNO microcontroller to control two DC servomotors). The tracking system was fitted and assembled together with a parabolic trough solar concentrator (PTSC) system to move it according to information come from the sensors so as to keep the PTSC always perpendicular to sun rays. The experimental tests have been done on the PTSC system to investigate its thermal performance in two cases, with tracking system (case 1) and without trackin
... Show MoreThe actual position and velocity of the sun and the moon were calculate through one year , and the satellite position and velocity components (x,y,z, vx, vy, vz) were calculate as well as the momentum component at inclination (116.5?) , argument of perigee (30?), longitude node angle (40?), eccentricity (0.01), for deferent perigee height (200,300,..,1000 km). The acceleration of perturbations which were calculated in this work are the sun and the moon attraction on the satellite, the solar radiation pressure, the atmospheric drag as well as the earth oblatness. The result show that the perturbation forces of atmospheric drag acceleration is effect by altitude and the sun, moon attractio
... Show MoreThe first chapter the importance of research and need for education scientists see that the roots of the use of a specimen Wheatley in learning and teaching back to Grayson Wheatley, one of the largest supporters of a modern construction, which lay the groundwork for the specimen stage and the form in which it is. That was attributed to him, often called his name called while some educators based learning strategy on the issue. He sees the learner in this model make him a meaningful understanding of problems during his progress, thereby acting with his colleagues to find solutions to them in small groups. He
Borders Search: Search by students is determined by th
... Show MoreThe Research topic seeks to analyze the "political risk and its component Terrorism Index," which consists of five indicators index, a number of terrorist operations, and the number of dead and wounded, and the size of the physical losses, based search sub-index analysis of material losses for the index terrorism and its impact on the indicators listed on the Iraq Stock Exchange Finance. As for the practical side, it has been use style gradient unrestricted and link the sample represented by ten banks listed on the Iraq Stock Exchange. was Statement the correlation and interaction of variables of the studySearch results produced that the volume of material losses is the most important indicator in the influential force and it explain a v
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