Background: With the increasing demand on esthetic orthodontic appliances, discoloration of clear elastomeric chains and modules remains an issue which concerns both orthodontics and patients. This in vitro study was conducted to evaluate the effect of exposing stretched clear elastomeric chains from six different companies (Ortho Technology, Ormco, Ortho Organizer, American Orthodontics, Opal and G&H companies) to three types of dietary media (tea, coffee and turmeric). Materials and methods: A total of 960 lengths of six modules were cut from short type elastomeric chain; 160 pieces from each brand. The specimens were stretched 50%, placed on plastic boards, and incubated in water at 37°C for 1 day, 7 days, 14 days and 28 days. Once a day, the specimens were immersed for ten minutes in the testing dietary media, washed and then returned back to the water container. Color measurements were made before and after incubation of the specimens. Digital image were taken by an SLR digital camera and the color changes were calculated according to CIE L*a*b* color space system by Adobe Photoshop program. The resulting data were statistically analyzed using ANOVA and LSD tests. Result: Elastomeric chains from AO, Opal and G&H companies were the most brands prone to discoloration. Ortho Organizers and Ortho Technology chains were the least prone to discoloration. Tea, coffee and turmeric solutions discolored elastomeric chains from all companies in a variable degree, however turmeric caused significantly more discoloration, followed by tea and least by coffee. The amount of discoloration caused by tea and coffee increases gradually to peak at 28 days, while most of the discoloration caused by turmeric was in the first day and reached a plateau in a week. Conclusion: To decrease the discoloration of clear elastomeric chains the consumption of colored dietary media especially spices like turmeric are to be discouraged.
In this paper, there are two main objectives. The first objective is to study the relationship between the density property and some modules in detail, for instance; semisimple and divisible modules. The Addition complement has a good relationship with the density property of the modules as this importance is highlighted by any submodule N of M has an addition complement with Rad(M)=0. The second objective is to clarify the relationship between the density property and the essential submodules with some examples. As an example of this relationship, we studied the torsion-free module and its relationship with the essential submodules in module M.
Marriage is a holly secret in Christian religion .So it id natural that its ceremonies acquired religious form .In general the marriage is contracted by minister of religion in presence of the two parties or by a proxy or presence of parents if it is necessary . And to make the condition of publicity for the marriage ,its procedures must be made before witnesses .Also the minister of religionhave to confirm the agreement of the two parties before beginning the procedures.The marriage ceremonies are made.These procedures are religious traditions that includes praying and make blessings and putting the rings in fingers by thepriest . The marriage is a holly secret performed by the crown pray according to the church religious traditions
The present study was included the isolation of Keratinophilic fungi from water samples taken from 19 indoor public swimming pools in Baghdad during four season (summer ,fall ,spring ,and winter). Isolation period was September 2011and September 2012 . Samples were collected from different places in swimming pool . Sixteen keratinophilic fungal species, belonging to twenty –one genera were isolated using Surface Dilution Plating (SDP) and Hair Bait Technique (HBT) . Aspergillus genus was the most frequent and occurrence (19.84%), followed by Trichophyton (11.60%) and Fusarium (7.59% ) . The most common fungal infection occurred in summer season (42.16%) , and the most frequent month manifestation of species occurred in August
... Show MoreMedia has become a common platform for communication as a tool of offense. English language has many insult words which are commonly used in the world of media. This study investigates the socio-pragmatic aspect of insulting in English news. It aims at identifying and analysing insult words and expressions used by news presenters. To specify the problem of the study, language has a harmful power that hurts the addressees and seriously harm their psychological well-being. The insulting words that are an element of all human languages are the source of this abusive power. The study questions sought to find out are if news presenters use insult words, which insult words, and in what social contexts. In this study, the descriptive method is use
... Show MoreThe study was aimed to investigate the morbidity of enteritis in goate from 2007 to 2011 by using 149 records contained veterinarian and breeding records from birth to yearling age to study factors refer to animals and that in relationship with enteritis morbidity included: breed, year, birth type, sex, birth weight, weaning weight, mother weight, season and age. General mean for enteritis incident rate was 0.94% and this not affected by birth type, sex, weaning weight, maternal weight, while significantly (p<0.05) affected by breed and birth weight and highly significant affect by year, season and age. This study indicated that local goats and shami have incidence rate received to 1.30% and 1.36% while for cross goats (local x Shami)
... Show MoreThe present study dealt with taxonomic characters of species Zygophyllum fabago L. in Iraq . this study included the exo-morphological characters which indicated that the species was sub-shrub with solid stem and swallow nodes ,with compound bifoliate and stipulate leaves, the flower is complete and perfect with clawed petals . stamen colored with scaly appendage , fruit capsule with ribs . Anatomical study of vegetative parts indicate that the sclerenchymal tissue was very diffuse in stem such as fibers and sclerides ( stone cells ) , the leaves were bifacial . The geographical distiribution of the species plants was studied . The results supported with photographs
In this ˑwork, we present theˑ notion of the ˑgraph for a KU-semigroup as theˑundirected simple graphˑ with the vertices are the elementsˑ of and weˑˑstudy the ˑgraph ofˑ equivalence classesˑofˑ which is determinedˑ by theˑ definition equivalenceˑ relation ofˑ these verticesˑ, andˑ then some related ˑproperties areˑ given. Several examples are presented and some theorems are proved. Byˑ usingˑ the definitionˑ ofˑ isomorphicˑ graph, ˑwe showˑ thatˑ the graphˑ of equivalence ˑclasses ˑand the ˑgraphˑof ˑa KU-semigroup ˑ areˑ theˑ sameˑ,
... Show MoreThe recent developments in information technology have made major changes in all fields. The transfer of information through networks has become irreplaceable due to its advantages in facilitating the requirements of modern life through developing methods of storing and distributing information. This in turn has led to an increase in information problems and risks that threaten the security of the institution’s information and can be used in distributed systems environment.
This study focused on two parts; the first is to review the most important applications of the graph theory in the field of network security, and the second is focused on the possibility of using the Euler graph as a Method Object that is employed in Re
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