The new novel polymers nanocomposites based modified chitosan (CS) blending with polyvinyl alcohol (PVA) and coated gold or silver nanoparticles (AuNPs), AgNPs) were synthesized from many sequence reactions as presented in (Scheme1, 2 and 3). By utilizing 1H-NMR spectroscopy, FTIR, and Field Emission Scanning electron microscope , the synthesized compounds have been identified. Molecular docking is studied, where operations are used to predict the binding status of compounds with the enzyme and to calculate the free energy (ΔG) of the compounds prepared. Also, the antibacterial activity regarding the synthesized compounds against two resistant pathogenic bacteria (G+) S. aureus and E. coli (G-) was examined in vitro compare with standard antibiotic (Amoxicillin). The cytotoxic effect of novel polymers nanocomposites against Human Lung Adenocarcinoma Cells line (A549) using MTT assay was used to estimate and compare with normal cell line Rat Embryonic Fibroblasts (REF), the (modified chitosan/PVA/Au) exhibited very excellent inhibition rate. Finally, the Acute Toxicity Test of these nanocomposities were examined showed non-toxicity of these nanocomposities and histological examination of internal organs: liver, lung and kidney related to treated group showed no changes but similar those of control group.
There have been many advances in the solar chimney power plant since 1930 and the first pilot work was built in Spain (Manzanares) that produced 50 KW. The solar chimney power plant is considered of a clean power generation that needs to be investigated to enhance the performance by studying the effect of changing the area of passage of air to enhance the velocity towards the chimney to maximize design velocity. In this experimental and numerical study, the reduction area of solar collector was investigated. The reduction area that mean changing the height of glass cover from the absorbing plate (h1=3.8cm, h2=2.6cm and h3=1.28cm). The numerical study was performed using ANSYS Fluent software package (version 14.0) to solve go
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(5)
أدى التغير السريع في البيئة الخارجية للمنظمة إلى ظهور حالة من التنافس الشديد مما زاد تخوف الشركات من فقدان الحصة السوقية والخسارة . مما حدا بالمنظمات إلى الاهتمام بوجود مدير يحمل صفات وخصائص قيادية لما فيه من ميزات في تنظيم الإنتاج ومقابلة الطلب وتقليل التكاليف وتطوير الأداء للحصول على ميزة تنافسية تحافظ او تزيد من حصتها السوقية وإرباحها .
تسعى الدراسة الى تحديد عدد من الاهداف كان اهمها معرفة الع
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(1)
Background: Many types of instruments and techniques are used in the instrumentation of the root canal system. These instruments and techniques may extrude debris beyond the apical foramen and may cause post-instrumentation complications. The aim of this study was to evaluate the amount of apically extruded debris resulted by using 4 types of nickel-titanium instruments (WaveOne, TRUShape 3D conforming files, Hyflex CM, and One Shape files) during endodontic instrumentation. Materials and methods: Forty freshly extracted human mandibular second premolar with straight canals and a single apex were collected for this study. All teeth were cut to similar lengths. Pre-weighted glass vials were used as collecting containers. Samples were randoml
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(3)
The present study aimed to identify the extent to which the content of social and national studies courses was included in interactive thinking maps in the educational stages in the Kingdom of Saudi Arabia, and to achieve the goal of the study, the researcher used the descriptive and analytical approach, and the study tool used consisted of a content analysis card; Where it included a list of the types of thinking maps, where the study sample consisted of all social and national studies courses at the elementary and intermediate levels, and it is (12) books for the student in its first and second parts, and after verifying the validity and reliability of the tool, it was applied to the study sample, and the study reached conclusions, inc
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(1)
Background: Systemic sclerosis (SSc) is a chronic autoimmune illness, which is consider by three main features: Sclerotic changes in the skin and internal organs, Vasculopathy of small blood vessels, Particular autoantibodies (1). The most important autoantibodies appeared significantly in SSc patients are anti-topoisomerase I autoantibody (Scl-70), anti-centromere autoantibody (ACA), and anti-RNA polymerase III autoantibody (RNAP3) (2). Anti-centromere antibodies (ACA) are infrequent in rheumatic conditions and in healthy persons but occur commonly in limited systemic sclerosis (CREST syndrome), and rarely appeared in the diffuse form of systemic sclerosis (3). Anti-Ro/SSA and antiLa/SSB, antibodies directed against Ro/La ribonucleoprot
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Background: Pulpotomy is an accepted treatment for the management of cariously exposed pulps in symptom free primary molars to achieve one of the most important goals for Pedodontists, which is the retention of the pulpally involved deciduous teeth healthy until the time of normal exfoliation. The purpose of this study was to evaluate the relative success of pulpotec, formocresol and Mineral Trioxide Aggregate (MTA) in cariously exposed primary molar teeth, using clinical and radiographical examinations. Materials and methods: Thirty nine children with 45 primary molars requiring pulpotomy were selected in this study, 15 teeth treated by each type of pulpotomy medicament. Clinical and radiographical follow up for the patients was performed
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