Background: This study was conducted to assess the effects of various beverages on the shear bond strength of light-cured orthodontic composite used to bond stainless steel orthodontic brackets on human teeth and to determine the site of bonding failure of this material. Materials and Methods: Fifty extracted human premolars were selected and randomly divided into five equal groups each with 10 teeth according to the beverage type (Control, One Tiger, Milk, Green tea and Coffee). After bonding, the teeth were immersed in specific beverages for 5 minutes twice daily with equal intervening intervals then washed and stored in distilled water at 37º C for the reminder of the day. The process was carried out for 30 days. The samples were then tested for shear bond strength using Tinius-Olsen testing machine with a crosshead speed of 0.5mm/minute. For adhesive remnant index, the enamel surface and bracket base of each tooth were inspected under magnifying lens (20X) of a stereomicroscope. Results: Milk, coffee and one Tiger energy drink reduced the shear bond strength of the light-cured composite significantly unlike the green tea. The predominant site of bond failure was between the bracket base and the adhesive leaving the composite on the tooth rather on the brackets base. Conclusions: Orthodontic patients should be instructed to reduce the intake of acidic and fatty beverages to prevent debonding of the orthodontic brackets.
The research aims to shed light on the importance of forensic accounting and its role in winning compensation claims against the company because of the ability of the forensic accountant (the judicial expert) to interpret and analyze the data. The research community represents the insurance companies in Iraq. The research sample was represented by the National Insurance Company. Coverage of the theoretical and deductive approach in covering the practical side, based on the financial records of the National Insurance Company for years of research.One of the most important conclusions reached by the researchers was that forensic accounting has a role
... Show MoreAbstract
The research aims to identify the level of effectiveness of the teaching practices of science and mathematics teachers in light of the national framework for future skills in Omani schools. To achieve the objectives of the study, the researchers used the descriptive approach, as he designed a note card consisting of (30) phrases distributed on three axes: basic skills, practical skills, and technical skills. After verifying the validity and reliability of the tools, they were applied to a sample of (116) teachers. The results of the research revealed that the level of effectiveness of the teaching practices of mathematics teachers has recorded a medium degree with a mean (3.05). The results a
... Show MoreClimate change in recent years has greatly affected the distribution of ground covers. Monitoring these changes has become very easy due to the development of remote sensitivity science and the use of satellites to monitor these changes. The aim of this research is to monitor changes in the spectral reflectivity of the Baghdad governorate center for the month (March, June, September, December) of the year 2021 using remote sensing and satellite images Sentinel 2 and knowing the climate imact on them. Fifty-one samples were selected for four types of ground cover (agricultural land, water, buildings and open space) and their spectral reflectivity was calculated using satellite images.
This study involved the effect of anew nickel (II) complexs with formla [NiL2(H2O)2].2.5ETOH where L=Bis[5-(p-nitrophenyL)-4-phenyL-1,2,4-traizole-3-dithocarbamato hydrazide] diaqua. nickel(II). Ethanol(2.5).and anti-cancer drug cyclophosphamide on specific actifity of two Liver enzymes (GOT,GPT) in the (Liver,kidney) tissues and on the creatinine Level in the kidney byUtilizing an invivosystem in femalmice.The result showed that inhibition in the activity of GPT and GOT enzymes in theLiver and in both nickel (II) complex and cyclophosphamide drug (CP) . mice weretreated with three doses (90,180,320) µg/mouse for three days for each group.The Liver show's the highest rate of GPT inhibition was about 97.43% at180µg/mouse regarding the ki
... Show MoreThe research aims to know the extent of the impact of the risks of foreign exchange centers represented in commitment risks, liquidity risks, and exchange rate risks on the continuity of the economic unit. The research in the light of its presentation of the intellectual, cognitive and applied contributions about the risks of foreign currency centers and the continuity of the economic unit, and represented the research community in the banking sector, and the sample included nine private commercial banks listed in the Iraq Stock Exchange, and they relied on the research on a time series consisting of four years that extended from one year 2017 to 2020. The research problem was the impact of the risks associated with foreign currency cent
... Show MoreVirtual reality, VR, offers many benefits to technical education, including the delivery of information through multiple active channels, the addressing of different learning styles, and experiential-based learning. This paper presents work performed by the authors to apply VR to engineering education, in three broad project areas: virtual robotic learning, virtual mechatronics laboratory, and a virtual manufacturing platform. The first area provides guided exploration of domains otherwise inaccessible, such as the robotic cell components, robotic kinematics and work envelope. The second promotes mechatronics learning and guidance for new mechatronics engineers when dealing with robots in a safe and interactive manner. And the thir
... Show MoreAbstract
On 11/1/2008 amounts of snows fell on various sections of Iraq, one of
which is Baghdad. The analysis process of climatic maps proved that the
advance trough of Sudanese depression towards the city is the reason behind
the formation of this weather state supported by could trough in the (500) mb
pressure level. .
The research concluded that the phenomenon of global warming
witnessed by the world recently had a main role in the occurrence of this
phenomenon due to the raise in earth temperature as a result of evaporation
rate increase leading to an increase in water vapor and cloud formation with
high tops and low bases which form sows with high rates accumulating at high
and moderate latitudes le