ABSTRACT Background:Hydrogen absorption and related degradation in the mechanical properties of Ni-Ti based orthodontic wires has been demonstrated following exposure to fluoride prophylactic agents. This study was designed to investigate the effects of three fluoride containing agents on the load deflection characteristics of heat activated nickel titanium arch wires during unloading phase. Material and method: Eighty specimens of heat activated nickel titanium arch wires were obtained from Ortho Technology Company, half of which had a 0.016 inch round and 0.019x0.025 rectangular. Ten specimens from both wire size were immersed in one of the tested fluoride prophylactic agents (neutral sodium fluoride gel, stannous fluoride gel or phos-flur mouth rinse) or in the controlled medium “normal salineâ€, and incubated at 37ËšC for sixty minutes. A Wp 300 universal material testing machine was modified and used to perform a three point bending test in a water path at 37ËšC ±1ËšC.The statistical difference between the different agents were analyzed using ANOVA and LSD tests. Results: The unloading forces at 0.5, 1.0, and 1.5 mm where significantly reduced especially in neutral sodium fluoride treated specimens. Conclusion: Based on the results founded in th study it might be preferred to use prophylactic agent with the least fluoride ions concentration.It can be concluded that the tested agents have only a limited effect on the load deflection behavior of the heat activated Ni-Ti wires, in a way that they do not have a clinically significant effect on the mechanical behavior of these wires.
The aim of the study was extraction of arial part of Euphorbia cyathophora constituents with methanol and evaluate its effect on mitotic index and total chromosomal aberration bone marrow cell and spleen cell in mice 200 gm of E. cyathophora fine powder was defatted then extracted by cold maceration 80% ethanol for seven days. The extract was filtered and dried in a rotary evaporator then the dried extract was suspended with water and consecutively extracted using chloroform, ethyl acetate for each. The aqueous layer was then mixed with 100ml methanol. These fractions are dried under reduced pressure to obtain the dry extract. Twenty-four Albino mice were used for the experiment. The animals were divided into four groups: Gr
... Show MoreThe necessities of steganography methods for hiding secret message into images have been ascend. Thereby, this study is to generate a practical steganography procedure to hide text into image. This operation allows the user to provide the system with both text and cover image, and to find a resulting image that comprises the hidden text inside. The suggested technique is to hide a text inside the header formats of a digital image. Least Significant Bit (LSB) method to hide the message or text, in order to keep the features and characteristics of the original image are used. A new method is applied via using the whole image (header formats) to hide the image. From the experimental results, suggested technique that gives a higher embe
... Show MorePhenomena of an abnormal genitalia was among some specimens of Cicindela aulica Dej.
Collected from Iraq. The fore tarsi of male were asymmetrical having its basal three segments
dilated and clothed beneath with fine bristles as in normal male. While those of the right leg
were found simple as in normal females. Dissection of the genialia of these specimens
showed that they were of two types of both male and female structures.
Fencing sport coaches seek fencers who have high velocity and work hard to develop it through training. The research problem lies on when measuring movement abilities through some tests. Manual measurement does not give reasonable impartiality of timing because there is a time-frame between the movement of the fencer and the speed of the movement of the human time setter. Therefore, the authors sought to design an electronic vest to evaluate movement abilities in foil fencers. The study design was experimental, with 12 Iranian foil fencers of the national team, who were divided into two equal groups of 6 fencers. Moreover, there were 12 students from Physical Education and Sport Sciences that worked on the scientific f
... Show MoreIn networking communication systems like vehicular ad hoc networks, the high vehicular mobility leads to rapid shifts in vehicle densities, incoherence in inter-vehicle communications, and challenges for routing algorithms. It is necessary that the routing algorithm avoids transmitting the pockets via segments where the network density is low and the scale of network disconnections is high as this could lead to packet loss, interruptions and increased communication overhead in route recovery. Hence, attention needs to be paid to both segment status and traffic. The aim of this paper is to present an intersection-based segment aware algorithm for geographic routing in vehicular ad hoc networks. This algorithm makes available the best route f
... Show MoreNAA Mustafa, University of Sulaimani, Ms. c Thesis, 2010 - Cited by 4
The therapeutic value of the phenolic component and pure thymol was well known; this study comprised the extraction of crude phenol from two plants (Thymus vulgaris and Artemisia annua) which contain thymol with pure thymol and evaluate their effect on hematological and histological by using three different concentrations of each plant extract and pure thymol to tested them on lab mice. All the mice were allowed free access to water and feed for 21 days in laboratory conditions; orally, pure water was administered to the control mice (group I), while groups II, III, and IV were given orally with T. vulgaris, A. annua, combination of last two crude phenol plant extract 50:50 and pure thymol respectively. The levels of CHO, TRI, and HDL were
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