Background: The fracture of instruments within root canal during endodontic treatment is a common incidence, fracture because of fatigue through flexure occurs due to metal fatigue, this study aimed to assess the effect of curvature angle and rotational speed on the cyclic fatigue of different type of Endodontic NiTi Rotary Instruments and compare among them. Materials and method: Three types of rotary instruments with tip size 0.25: ProTaPer F2 (Densply, Malifier) Revo-S SU( 0.06 taper, MicroMega) and RaCe system (0.06 taper, FKG, Dentaire), Forty file of each instrument were used within two canals with angle of curvature (40 &60 )at two speed (250&400)RPM, twelve group were formed for all instruments(total number=120),ten file for each group. The testing canals customized within stainless steel block covered with glass face, the time to fracture recorded and the mean of cycles to fracture (MCF) detected for each instrument. Data were analyzed statistically by ANOVA, LSD and Independent T-test at 5% significant level. Result: there was a highly significant difference of curvature angle and significant difference of rotational speed on the fracture resistance of instruments. RaCe revealed the best fracture resistance followed by ProTaper then Revo-S that showed the less resistance. Conclusion: The rotary instruments more prone to fracture when used at more curvature angle and higher rotational speed, as well as the rotary instruments differ from each other according to manufacturing process, taper, cross section and other factors.
Perhaps masculinity and femininity in our Arabic language are among the linguistic issues that have occupied the attention of researchers, ancient and modern. Many books, works, and research have been written on this subject, but there is still something in it that must be revealed, clarified, and established, as the ancients did not classify the feminine and masculine into real, metaphorical, auditory, analogical,
The study aims to identify the extent the academics in colleges of applied sciences are familiar with the themes of the national strategy of education 2040 in the Sultanate of Oman. The researchers used the descriptive approach, as well as they adopted a questionnaire with five dimensions as a tool for data collection, which was applied to (120) academics. The results showed that the academics of the applied colleges' familiarity with the National Strategy for Education 2040 in the Sultanate of Oman is average. The study also found that there were no statistically significant differences in the academics estimates of the extent of the Colleges of Applied Sciences academics’ familiarity with the themes of the National Education 2040 Str
... Show MoreGod Almighty put in his great book secrets that do not end, and wonders that do not expire, for he is the one from which the scholars are not satisfied, and he does not create due to the multitude of response, and it is the comprehensive and inhibitory book that God conceals to the worlds, and he challenged the two heavyweights to come up with something like it.
At all times, issues arise in the Noble Qur’an that fit the needs of the people of that time and their culture, for it is an eternal book, characterized by the ability to give, extend and respond to addressing the problems of the age and its variables, when the Arabs had little luck at the time of the message’s descent from the scientific culture, and their proficienc
... Show MoreThe skill high-jump scoring is based on mechanical and physical abilities. The most important of all is the strength used by the player from the moment of preparation to the moment of scoring, which led the researchers to study the characteristics of the series of power chain functions of this skill according to (Biosyn System) The players of the national team's back line have a handball to find out the relationship between the properties of the power chain curve and the accuracy of the high jump to the upper and lower target angles. The aim of the research was to identify the values of the Force Series variables for the skill of the high-jump curve of the handball as well as the relationship between the properties of the power chain functi
... Show MoreThe rapid development of information technology and its use in all areas has had a positive impact on all areas, and financial markets have had a share of this development through the use of an electronic trading system to settle transactions, enhance transparency and disclosure in all activities of these markets and revitalize their performance.
The reason for choosing this topic is that it is a very important topic for what modern technology addresses in trading operations in financial markets. It is worth noting that these innovations have eliminated the need for direct contact with people, but through the Internet and telephone networks, and the new technology has reduced the costs of building systems
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Praise be to God, and may blessings and peace be upon the Messenger of God. As for:
The Noble Qur’an is the constitution of life, and a comprehensive educational approach that deals with individuals comprehensively, as it organizes worldly and eschatological life, and it is a curriculum concerned with organizing life starting with individuals and the family until the establishment of states, and from its comprehensiveness is reform, guidance and establishing boundaries. They have a disease in their hearts. They are exposed to this and are trying, by falsehood, to subjugate the Islamic world with man-made laws set by the West. Their aim is to distance people from
... Show MoreInfluence of combined square nozzle with helical tape inserted in a constant heat flux tube on heat transfer enhancement for turbulent airflow for Reynolds number ranging from 7000 to 14500 were investigated experimentally. Three different pitch ratios for square nozzle (PR = 5.8, 7.7 and 11.6) according to three different numbers of square nozzle (N = 3, 4 and 5) and constant pitch ratios for helical tape were used. The results observed that the Nusselt number and friction factor for combination with winglets were found to be up to 33.8 % and 21.4 %, respectively higher than nozzle alone for pitch ratio PR=5.8. The maximum value of thermal performance for using combination with winglets was about 1.351 for pitch ratio= 5.8. Nusselt numb
... Show MoreThe research dealt with the analysis of the relations between the GDP of the agricultural sector in Iraq, oil prices, the exchange rate and the GDP both on the short term and long term. The research adopted data analysis for the period from 1980-2019 using the ARDL model. the results indicate the existence of long-term relationships between oil prices and the prices of each agricultural commodity at a significance level of 5%. Also, oil prices have a negative consequence on agricultural production in Iraq, and the Iraqi economy is a rentier economy that depends mainly on oil as a source of income and budget financing.
Proteus mirabilis isolates have been intensively researched for their capacity to cause urinary tract infections (UTIs) and their swarming motility, although little is known about this phenomenon. Probiotic Lactobacillus species, which are beneficial bacteria, are being studied worldwide as therapeutic and preventative agents against bacterial infections. This study investigated Lactobacillus supernatants as a potential new treatment against Proteus mirabilis. In addition to testing their antimicrobial and anti-swarming activities, the research also aimed to understand the genetic mechanisms behind the observed phenotypic changes. Methods. A total of 150 urine specimens were collected from UTI patients at various hospitals in Baghdad. Dire
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