Background: During acrylic resin processing, the mold must be separated from the surface of the gypsum to prevent liquid resin from penetrating into the gypsum, and water from the gypsum seeping into the acrylic resin. For many years, tin foil was the most acceptable separating medium, and because it's difficult to apply, a tin-foil substitute is used. In this study, olive oil is used as an alternative to tin foil separating medium for first time, and evaluating its effect as a separating medium on some mechanical properties such as (indentation hardness and transverse strength) of acrylic resins denture base comparing it with those processed using tin-foil and tin foil substitute such as (cold mold seal) separating medium. Materials and Methods: One hundred Twenty four acrylic resins samples (124) were prepared falling in two main groups: (heat and cold-cured acrylic denture base resins), for each group three types of separating medium were used and five tests (10 samples) for each test were carried out, and (4) samples for the chemical composition. Results: Tin foil is one of the most satisfactory separating media in getting the best properties when using it as a separating medium, while, a statistically no-significant difference have been noticed between olive oil and cold-mold seal samples concerning mechanical properties of tested groups. Infrared spectroscopy analysis showed that, no changes were found in the chemical composition of both heat and cold-cured acrylic resins denture base after using olive oil as a separating medium. Conclusion:The present study concluded that olive oil may be used as a substitute for tin foil and cold – mold seal separating medium in processing both heat and cold – cure acrylic resin denture base.
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The thermal and electrical performance of different designs of air based hybrid photovoltaic/thermal collectors is investigated experimentally and theoretically. The circulating air is used to cool PV panels and to collect the absorbed energy to improve their performance. Four different collectors have been designed, manufactured and instrumented namely; double PV panels without cooling (model I), single duct double pass collector (model II), double duct single pass (model III), and single duct single pass (model IV) . Each collector consists of: channel duct, glass cover, axial fan to circulate air and two PV panel in parallel connection. The temperature of the upper and lower surfaces of PV panels, air temper
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Quadrotors are coming up as an attractive platform for unmanned aerial vehicle (UAV) research, due to the simplicity of their structure and maintenance, their ability to hover, and their vertical take-off and landing (VTOL) capability. With the vast advancements in small-size sensors, actuators, and processors, researchers are now focusing on developing mini UAV’s to be used in both research and commercial applications. This work presents a detailed mathematical nonlinear dynamic model of the quadrotor which is formulated using the Newton-Euler method. Although the quadrotor is a 6 DOF under-actuated system, the derived rotational subsystem is fully actuated, while the translational subsystem is under-actuated. The der
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Background: An individual’s quality of life is adversely affected by overactive bladder (OAB) symptoms. The key element that characterizes OAB is urgency which together with nocturia and urge urinary incontinence, are considered the most irksome symptoms. The side effects of the anticholinergic medication have caused a significant number of patients to discontinue their treatment. More recently, there has been research conducted on the potential correlation between an anticholinergic burden and the development of dementia. The detrusor muscle has been demonstrated to relax as a result of the activation of β3 adrenoceptors, which in turn facilitated the development of the first β3 adrenoceptor agonist. Mirabegron is the initial m
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الخلاصة
یعد والت وتمن شاعرا استثنائیا سواء أكان ذلك في المكانة التي یحتلھا في الأدب الأمریكي او في نمط
اع t ذا الإیق t لة ھ t ة وص t وافقي خاص t اع الت t تخدامھ الإیق t ي اس t دي ف t ر تقلی t عرا غی t الشعر الذي یكتبھ. لقد كتب وتمن ش
ل t ة للتوص t ف الطبیع t وافقي لوص t اع ا لت t ن الإیق t تخدم وتم t ر ، اس t بوحدة الكون الذي عبر عنھ في شعره.وبمعنى آخ
نص t ل ال t جام داخ t رابط وانس t یج مت t ھ نس t ق انظم t دف لخل t ھ تھ t اھره أدبی t واف
Background: Oocytes are susceptible to alterations in the various fatty acid contents of follicular fluid (FF), which may influence maturation and embryogenesis. Different fatty acids exert various effects on intracytoplasmic sperm injection (ICSI), which needs further studies to uncover the involved mechanisms. Objectives: To assess FF fatty acids in women undergoing ICSI and to correlate them with ICSI parameters, namely the total count of aspirated oocytes, oocyte maturation rate, fertilization rate and percentage of good-quality embryos. Methods: Fifty women undergoing ICSI were enrolled in this cross-sectional study. FF samples were collected during oocyte retrieval and were analyzed for fatty acids using gas chromatography. Fa
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The present study has been carried out to estimate heavy metals mobility, bioconcentration and transfer from polluted soil to roots tissues and from roots tissues to aerial parts using bioconcentration factor and translocation factor. Soil samples and the biomass of the eight vegetable species have been collected during summer season, 2019 from four different sites in Wadi Al-Arg, Taif Governorate, KSA. In general, heavy metals content of soil samples in site III and IV have recorded elevated values compared with those of site I and II. The soil from site IV has shown the highest concentration of Mn, Ni, Cr, Pb, Cu, and Cd amounted 31.63, 14.05, 13.56, 22.79, 31.02 and 2.98 mg/kg dry soil respectively, while the soil from site III has sh
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