Objective Advantageous properties of silicone elastomer made it one of the favorable materials in maxillofacial prosthesis construction, but these properties may change after months of usage or after pigments addition. This study aimed to define the optimum concentration for a mixture of two types of intrinsic pigments that added to VST-50 maxillofacial silicone material and study their effects on mechanical properties before and after artificial aging. Methods After the pilot study was conducted, 0.1% by weight of rayon flocking and 0. 2% by weight of burnt sienna intrinsic pigment concentration was selected because of improvement in tested mechanical properties of VST-50 maxillofacial silicone. A total of one hundred and eighty samples were prepared and divided into three equal test groups (tear strength, hardness and surface roughness), 60 samples were made for each test. Each test group includes 6 subgroups with 10 samples made for each one of them to test before and after (75 hours and 150 hours) of artificial aging. FTIR and XRD tests also were used in the study. Results The results show for pigmented samples before artificial aging that some mechanical properties had improved. After artificial aging, both periods resulted in non- significant decrease in tear strength while hardness and surface roughness had highly significantly increased. FTIR test and XRD test shows no chemical reaction between pigments and silicone. Conclusion The addition of intrinsic pigments had improved hardness and tear strength of maxillofacial silicone but after subjecting it to artificial aging, all of the tested properties had adversely affected.
Background: Polymethylmethacrylate (PMMA) is the most ‎commonly used mâ€aterial in denture construction. This material is ‎far from ideal in fulfilling the‎ mechanical requirements, like low impact and transverse strength and poor thermal conductivity are present in this material. The purpose of this study was to study the effect of addition a composite which include 1%wt silanized silicone dioxide nano fillers (SiO2) and 1wt% oxygen plasma treated polypropylene fiber (PP) on some properties of heat cured acrylic resin denture base material (PMMA). Materials and methods: One hundâ€red (100) prepared specimens were divided into five groups according to the tests, each group consisted of 20 specimens and t
Background: Postoperative nausea and vomiting (PONV) are one of the most common complaints following laparoscopic cholecystectomy.
Objective: This study was designed to compare the effects of dexamethasone, metoclopramide, and their combination on preventing PONV in patients undergoing laparoscopic cholecystectomy.
Methods: A total of 135 patients enrolled in the study. American Society of Anesthesiologists (ASA) physical status I and II patients were included in this randomized, double blind, placebo-controlled study. Patients were randomly assigned to group A administered 8mg iv dexamethasone, group B received metoclopramide 10 mg, group C received combination of 8mg de
... Show MoreAlthough Israel's national security strategy, shaped by Ben Gurion in the 1950s, has remained steadfast, Israeli leaders have been keen to adapt and change some of its means and tools to maintain its national security. These changes were a response and adaptation to the complex and geostrategic transformations in the region since the end of the cold war. Traditional challenges to Israel's national security have declined as unconventional challenges have increased. This shift has adversely affected the efficiency and effectiveness of Israel's national security strategies. It has become necessary for Israel to confront regional actions taken by minor states and regional actors that have ensured the accumulation of its military capabilities. M
... Show MoreIn recent years, there has been expanding development in the vehicular part and the number of vehicles moving on the roads in all the sections of the country. Arabic vehicle number plate identification based on image processing is a dynamic area of this work; this technique is used for security purposes such as tracking of stolen cars and access control to restricted areas. The License Plate Recognition System (LPRS) exploits a digital camera to capture vehicle plate numbers is used as input to the proposed recognition system. Basically, the proposed system consists of three phases, vehicle license plate localization, character segmentation, and character recognition, the
... Show MoreThe pharmacokinetics and bioequivalence of a newly developed extended-released (ER) tablet containing 400 mg pentoxifylline as a test product was compared with the reference brand product Trental® 400 mg ER tablet produced by Sanofi-Aventis. Two separate studies were conducted simultaneously. The first study was conducted under fasting condition, whereas, the second study was conducted under fed condition; using the same batches of the test and reference products in both studies. In each study, both products were administered to 32 healthy male adult volunteers applying a single-dose, two-treatment, two-period, two-sequence, randomized crossover design with one-week washout period between dosing. Twenty two blood samples we
... Show MoreThis study aimed to investigate the incorporation of recycled waste compact discs (WCDs) powder in concrete mixes to replace the fine aggregate by 5%, 10%, 15% and 20%. Compared to the reference concrete mix, results revealed that using WCDs powder in concrete mixes improved the workability and the dry density. The results demonstrated that the compressive, flexural, and split tensile strengths values for the WCDs-modified concrete mixes showed tendency to increase above the reference mix. However, at 28 days curing age, the strengths values for WCDs-modified concrete mixes were comparable to those for the reference mix. The leaching test revealed that none of the WCDs constituents was detected in the leachant after 180 days. The
... Show MoreThin films of tin sulfide (SnS) were prepared by thermal evaporation technique on glass substrates, with thickness in the range of 100, 200 and 300nm and their physical properties were studied with appropriate techniques. The phase of the synthesized thin films was confirmed by X-ray diffraction analysis. Further, the crystallite size was calculated by Scherer formula and found to increase from 58 to 79 nm with increase of thickness. The obtained results were discussed in view of testing the suitability of SnS film as an absorber for the fabrication of low-cost and non toxic solar cell. For thickness, t=300nm, the films showed orthorhombic OR phase with a strong (111) preferred orientation. The films deposited with thickness < 200nm deviate
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