Background: The new concepts and technologies continue to change the dynamics of endodontic practices in the world. Rapid and significant changes in techniques, instrument design, and the type of metals used to manufacture endodontic instruments which have been made during the last few years in an attempt to overcome canal preparation errors. The purpose of this study is to measure and compare canal transportation and centering ability of Self Adjusting File with two rotary nickel-titanium (Ni-Ti) systems, ProTaper and BioRaCe at different levels. Material and Methods: Forty five distal roots of mandibular first molars with moderate curvature were selected using Schneider method. Roots were divided randomly into 3 groups of 15 each and were scanned using Computed Tomography (Initial scan). After canal preparation with ProTaper (group A), BioRaCe (group B), and Self Adjusting File (group C) the roots were rescanned (Final scan), the degree of canal transportation and centering ability were assessed at apical (4 mm), middle (6 mm), coronal (9 mm) sections using computed tomography. The collected data were statistically analyzed using ANOVA and Least Significant Difference tests. Results: There were no statistically significant differences among the groups at level 4 mm and level 9 mm (P ? 0.05). However, at level 6 mm there was a highly significant difference between (A) and (B) groups (P ? 0.01) and there was a significant difference between (A) and (C) groups (P ? 0.05). There were no statistically significant differences among different levels of (A) and (C) groups (P ? 0.05), while (B) group showed a highly significant difference between 4 mm and 9 mm levels and between 6 mm and 9 mm levels (P ? 0.01). Regarding canal centering ability, there was no statistically significant difference among the three groups at different levels (P ? 0.05)., while (B) group showed a significant difference between 4 mm and 9 mm levels (P ? 0.05), and a very highly significant difference between 6 mm and 9 mm levels (P ? 0.001). Conclusion: The study demonstrated that canal preparation with the three designs of Ni-Ti instruments produced canal transportation. Self Adjusting File group showed less canal transportation than ProTaper group. There was a comparable value of canal centering ability among different levels in each group except in BioRaCe group.
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In this paper the method of singular value decomposition is used to estimate the ridge parameter of ridge regression estimator which is an alternative to ordinary least squares estimator when the general linear regression model suffer from near multicollinearity.
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Between the duality of sound and image, the completeness of the actor’s personality at the director comes to announce the birth of the appropriate theatrical role for that character as the basic and inherent element of the artwork, within his working system in the pattern of vocal behavior as well as motor/signal behavior as he searches for aesthetic and skill proficiency at the same time.
This is done through the viewer’s relationship with the theatrical event, which the director considers as an area of active creative activity in relation to (the work of the actor) through vocal recitation and the signs it broadcasts in order to fulfill the requirements of the dramatic situation and what it requires of a visual vision drawn in t
تحلل الورقة الحالية تمثيل كاريل تشرشل للصورة النمطية للمرأة في Top Girls (1982). تُظهر المسرحية كيف وصلت النساء في نضالهن لمحاربة اضطهاد الرجال عبر التاريخ ، إلى مستوى من القوة والحرية يستخدمان للسيطرة على جنسهن دون شفقة. مارلين ، الشخصية المركزية في هذه المسرحية ، هي امرأة تبنت الصفات الذكورية إلى أقصى الحدود. لتسلق سلم النجاح إلى قمته ، تضحي مارلين بطفلها وعائلتها وحبها. كما تعرض المسرحية النساء الصامتات والم
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Ibuprofen is one of the most important members of NSAIDs, named aryl propionic acid derivative. Isatin (1H-indole-2,3-dione) is an important molecule of heterocyclic compounds that have many biological activities. This work illustrates the synthesis of new ibuprofen-isatin derivatives by connecting ibuprofen hydrazide with different isatin derivatives by a condensation reaction, followed by characterization by fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The anti-inflammatory activity was evaluated by using the egg-white induce edema method for all the synthesized compounds (5-8), the compounds 5 and 6 showed better anti-inflammatory activity than ibuprofen as a standard compoun
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The study aimed at clarifying the contradictions of the general industrial companies despite the investment allocations and the government investment expenditure on manufacturing activities under the so- called rehabilitation programs. However, this did not contribute to a certain extent in the growth and industrial leap in the direction of developing the activities of the sector Industrial sector in Iraq because of the lack of adoption of a number of basic principles towards the need to take priority of investment in the field of manufacturing and industrial decision-making in the restructuring of industry according to the priorities of investment in light of the international industrial trend, Tosmarah available to the manufact
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Recently, a new secure steganography algorithm has been proposed, namely, the secure Block Permutation Image Steganography (BPIS) algorithm. The new algorithm consists of five main steps, these are: convert the secret message to a binary sequence, divide the binary sequence into blocks, permute each block using a key-based randomly generated permutation, concatenate the permuted blocks forming a permuted binary sequence, and then utilize a plane-based Least-Significant-Bit (LSB) approach to embed the permuted binary sequence into BMP image file format. The performance of algorithm was given a preliminary evaluation through estimating the PSNR (Peak Signal-to-Noise Ratio) of the stego image for limited number of experiments comprised hiding
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This paper presents a study (experimentally) for strengthening reinforced concrete (RC) beams with Near-Surface-Mounted (NSM) technique. The use of this technique with CFRP strips or rebars is an efficient technology for increasing the strength for flexure and shear or for repairing damaged reinforced concrete (RC) members. The objective of this research is to study, experimentally, RC beams either repaired or strengthened with NSM CFRP strips and follow their flexural behavior and failure modes. NSM-CFRP strips were used to strengthen three RC beam specimens, one of them was initially strengthened and tested up to failure. Four beam specimens have been initially subjected to preloading to 50% and 80% of ultimate load. Two of the sp
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