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 effect of water stress induced by using polyethylene glycol (PEG-6000) on germination of seeds and growth of seedlings of Silybum marianum was studied. Two concentrations of PEG were used to get two water stresses (-0.4 & -0.8 bar) as well as the control for comparison. The results showed a significant decrease (P<0.05) in germination ratio compared with the control. The ratio did not slow down to less than 50% which indicates the ability of the seeds to resist water stress to some extent. Also, a significant decrease (P<0.05) in the length of shoot and root was observed compared with the control. This plant showed
... Show Morethis research aims to identify the impact of teaching with ana logies in collection of chemistry students grade average.And direction in order to verify to the zero hypothesis has been formulated and validated,The researcher conducted experiment lasted a full semester as experimental design was chosen (exactly)two equal one pilot and another officer.The research community has been selected one of intentional Middle School of the Education Directorate in B aghdad Karkh second either search sample consisted of (68) students from second grade average (34 ) Students for each group randomly selected research groups was equal to the following variables (lifetime months,parent of first grade chemistry degrees average test informat
... Show MoreThe study aimed to identify the E-leadership practice at Princess Nora Bint Abdul Rahman University and to explore the obstacles that are facing the leaders in the implementation of E-leadership, in addition to find mechanisms to improve the practice of electronic driving at the university in light of the Corona pandemic. A descriptive analytical approach was used by depending on a questionnaire to collect the needed data. The study sample consisted of (139) heads of departments, attorneys' colleges and support Deanships universities. The study results showed that E-leadership employment recorded a medium to high degree. Especially at university, that publishing decisions electronically and uses technical means in providing its services.
... Show MoreA reinforced concrete frame is referred as "RIGID FRAMES". However, researches indicate that the Beam-Column joint (BCJ) is definitely not rigid. In addition, extensive research shows that failure may occur at the joint instead of in the beam or the column. Joint failure is known to be a catastrophic type which is difficult to repair.
This study was carried out to investigate the effect of hoops and column axial load on the shear strength of high-strength fiber reinforced Beam-Column Joints by using a numerical model based on finite element method using computer program ANSYS (Version 11.0). The variables are: diameter of hoops and magnitude of column axial load.
The theoretical results obtained from ANSYS program are in a good a
The current research seeks to know the difficulties in memorizing literary texts with fourth grade students from teachers’ point of view of and students
The research contains a community of (10,870) students from schools affiliated to the Directorate of Karkh, second and the number of schools for boys and girls (79) School and the number of teachers (349) who are specialized in teaching Arabic language to fourth grade preparatory students and there was a section of a randomly sample of each of the students, teachers and schools .
Some actions which can be listed below:-The survey which was done by the researcher for the views of the two samples from teachers and students as the number of teachers covered in this research (20) and
The last four decades have witnessed a number of rapid and successive international changes in terms of future impacts and orientations. International economy has transformed into a competitive small village due to the information technology revolution and the liberation processes and the economic openness that the market witnesses, there became one market and the activists in this international market are not governments only but rather international organizations and huge multinational corporations where each spares no effort to take every opportunity and face challenges within the frame of removing all impediments and release transactions under the auspices of these global developments, the idea of creating Islamic
... Show MoreThe current research aims to identify the " impact of strategic warheads numbered ( NHT) in the collection average second grade students in the article of history). " To achieve this, I assumed the researcher that there is no different between the statistically significant the average score for the collection of experimental group who teaches the Arab Islamic history on and a strategic warheads numbered and the average score for the collection of the control group who were studying the same article according to the classic method ( traditional) . The study sample consisted of 64 students from the second grade average in the secondary warka bin nawfal in the general Directorate for education first karkh in Baghdad for the annual cources 2
... Show MoreBackground: The treatment of an ovarian cyst relies on its nature, the discrimination of benign and malignant cysts is, therefore of crucial importance, and in spite of the continuous improvement of diagnostic means, it remains sometimes impossible to differentiate functional from organic (malignant or not) ovarian cysts. The therapeutic decision will search for the main midway between cancer’s negligence and the fear of performing an unnecessary surgical operation for an ovarian cyst.Objective: To review of 116 cases of ovarian cystic diseases aiming in identify proper management and reducing unnecessary surgical intervention.Methods: A retrospective study was conducted at Al-Elwiya maternity teaching hospital/ Baghdad/ Iraq. One hund
... Show MoreCoating materials have an extraordinarily high use, for industrial or technical applications. This study compares the effect of short glass and polypropylene fibers on the hardness, water absorption and anti-bacterial activity of acrylic composites against Gram positive (Streptococcus sp.) and Gram negative bacteria (E.coli, Pseudomonas aeruginosa, Klebsiella sp.).To prepare acrylic polymer and acryliccomposites (glass fibers and polypropylene fiber) the weight fraction (20 %,) (v0= lama acrylic, v1= lama acrylic/ glass fiber, and v2= lama acrylic /poly propylene fiber), of chopped glass fibers and polypropylene were added to acrylic , the resultant solution was stirred by hand for 5 minutes, using the Hand-lay-up technique.
Results s
ترجمۀ شعر به آهنگ موسیقی از شاهکارهای فکری که تولیدی علمی ترجمی می آراید به شمار میرود ، چیزی مورد نا راحتی ونومیدی نسبت به مترجم وجود ندارد ، اگر وی در این راه با تلاش کردنی سیر می رود تا ثمره های آن ترجمه می چیند .
روش پژوهشگر در آنچه از ترجمۀ ابیات شعر فارسی بر آمد ، روشی نوینی می داند که آن بر هماهنگی آواز الفاظ با یکدیگر اتکای می کند تا ترجمه دارای آوازی وهماهنگی ، به مرتبه ای موسیق
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