This study aims to evaluate the biocompatibility of a novel filler material intended to improve the longevity of polymer systems used in prosthetics in respect of cytotoxicity and skin irritation. RTV50F silicone elastomer incorporated with various percentages of hexagonal boron nitride (H-BN) (0.1, 0.3, 0.5, 0.7, and 1 wt%) have been tested. Silicone without H-BN was utilized as the control for comparison. The in vitro cytotoxicity test includes specimens (n=18) with 10 mm in diameter and 2 mm in thickness applied directly to the normal human fibroblast cell line (NHF) and incubated for 72 hours, then 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the cell viability. The skin irritation test was conducted in vivo, in which specimens (n=12) with 25 mm × 25 mm dimensions were applied on the back of 5 different rabbits for 4 hours, then the skin response was evaluated after 24, 48, and 72 hours. The acquired in vitro data were statically analyzed using one-way ANOVA and post-hoc Tukey’s tests with GraphPad Prism 8, where P-value < 0.05 was considered statistically significant. The H-BN powder and silicone specimens were studied via field emission scanning electron microscopy (FE-SEM). The results revealed a negligible effect of maxillofacial silicone on cell viability after 72 hours of incubation, only one group (1wt%) showed a significant difference compared to the control group but the toxicity percentage didn’t exceed 30% of cell viability and there was no skin irritation during the in vivo test.
The internal observing system is considered a cornerstone for the high management in all the systems. It aims at defending the things for waste and increasing efficient and application the rules and regulations and constrictions. To easier for the high management activity in the internal observing system which in presented and practiced and to what extent can depend on it. Thus it goes to evaluate the internal observing system periodically to check the weak points in that system so as the find out the mistake, in the construction of the system or mistake, by indication of the workers. The importance of this study is represented in the need of increasing the coactivity in the internal observing system so as to be in touch with the new tre
... Show MoreEnergy efficiency is a significant aspect in designing robust routing protocols for wireless sensor networks (WSNs). A reliable routing protocol has to be energy efficient and adaptive to the network size. To achieve high energy conservation and data aggregation, there are two major techniques, clusters and chains. In clustering technique, sensor networks are often divided into non-overlapping subsets called clusters. In chain technique, sensor nodes will be connected with the closest two neighbors, starting with the farthest node from the base station till the closest node to the base station. Each technique has its own advantages and disadvantages which motivate some researchers to come up with a hybrid routing algorit
... Show MoreGlassy polymers like Poly Mathyel Metha Acrylate are usually classified as non-porous materials; they are almost considered as fully transparent. Thin samples of these materials reflect color changing followed by porous formation and consequently cracking when exposed to certain level of ?-irradiation. The more the dose is the higher the effect have been observed. The optical microscope and UV-VIS spectroscopy have clearly approved these consequences especially for doped polymers.
Ultimate oil recovery and displacement efficiency at the pore-scale are controlled by the rock wettability thus there is a growing interest in the wetting behaviour of reservoir rocks as production from fractured oil-wet or mixed-wet limestone formations have remained a key challenge. Conventional waterflooding methods are inefficient in such formation due to poor spontaneous imbibition of water into the oil-wet rock capillaries. However, altering the wettability to water-wet could yield recovery of significant amounts of additional oil thus this study investigates the influence of nanoparticles on wettability alteration. The efficiency of various formulated zirconium-oxide (ZrO2) based nanofluids at different nanoparticle concentrations (0
... Show MoreIn digital images, protecting sensitive visual information against unauthorized access is considered a critical issue; robust encryption methods are the best solution to preserve such information. This paper introduces a model designed to enhance the performance of the Tiny Encryption Algorithm (TEA) in encrypting images. Two approaches have been suggested for the image cipher process as a preprocessing step before applying the Tiny Encryption Algorithm (TEA). The step mentioned earlier aims to de-correlate and weaken adjacent pixel values as a preparation process before the encryption process. The first approach suggests an Affine transformation for image encryption at two layers, utilizing two different key sets for each layer. Th
... Show MoreThe wear behavior of alumina particulate reinforced A332 aluminium alloy composites produced by a stir casting process technique were investigated. A pin-on-disc type apparatus was employed for determining the sliding wear rate in composite samples at different grain size (1 µm, 12µm, 50 nm) and different weight percentage (0.05-0.1-0.5-1) wt% of alumina respectively. Mechanical properties characterization which strongly depends on microstructure properties of reinforcement revealed that the presence of ( nano , micro) alumina particulates lead to simultaneous increase in hardness, ultimate tensile stress (UTS), wear resistances. The results revealed that UTS, Hardness, Wear resistances increases with the increase in the percentage of
... Show MorePortable and stationary electrical generators became quite popular in Iraq soon after the shortage in national electrical
energy after 2003. Multi step risk assessment process is used in this study in the assessment of risks caused by
contamination of indoor air by lead particles emitted from domestic electrical generators. Two portable electrical
generators are tested under controlled indoor conditions (Radial LG (0.9 keV) fueled with benzene and oil and TigMax
(3 keV), fueled with benzene only). Lead particles in air were sampled by using portable dust sampler (Sniffer, L-30).
The atmospheric particulate sampling process is carried out in a flat located in the first floor of a three stories building
located in Baghdad
This paper describes the problem of online autonomous mobile robot path planning, which is consisted of finding optimal paths or trajectories for an autonomous mobile robot from a starting point to a destination across a flat map of a terrain, represented by a 2-D workspace. An enhanced algorithm for solving the problem of path planning using Bacterial Foraging Optimization algorithm is presented. This nature-inspired metaheuristic algorithm, which imitates the foraging behavior of E-coli bacteria, was used to find the optimal path from a starting point to a target point. The proposed algorithm was demonstrated by simulations in both static and dynamic different environments. A comparative study was evaluated between the developed algori
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