Background: Many types of instruments and techniques are used in the instrumentation of the root canal system. These instruments and techniques may extrude debris beyond the apical foramen and may cause post-instrumentation complications. The aim of this study was to evaluate the amount of apically extruded debris resulted by using 4 types of nickel-titanium instruments (WaveOne, TRUShape 3D conforming files, Hyflex CM, and One Shape files) during endodontic instrumentation. Materials and methods: Forty freshly extracted human mandibular second premolar with straight canals and a single apex were collected for this study. All teeth were cut to similar lengths. Pre-weighted glass vials were used as collecting containers. Samples were randomly divided into four groups with 10 samples in each group: Group A instrumentation by WaveOne reciprocating file, Group B instrumentation by TRUShape 3D rotating files, Group C instrumentation by Hyflex CM rotating files and Group D instrumentation by One Shape rotating file. A total volume of 7 ml of sodium hypochlorite was used for irrigation in each sample. Apical patency confirmed and maintained by a size #15 K-File. All canals were instrumented up to a size #25. After completion of endodontic instrumentation, vials were then stored in an incubator for 5 days at 68o C for dryness. Then vials are weighted again, and the pre-weight subtracted from the post-weight, the weight difference resembled the amount of apically extruded debris from the apical foramen during root canal instrumentation. Data obtained were statistically analysed by using ANOVA and LSD tests. Results: The results showed that the Hyflex CM Group (C) has statistical significant lowest apically extruded debris as compared to other groups of this study (P ≤0.05), while the TRUShape Group (B) has statistical significant lowest apically extruded debris as compared to One Shape Group (D) and WaveOne Group (A), while the WaveOne Group (A) showed the highest value of apically extruded debris (p ≤0.01). The result showed that all groups resulted in apical extrusion of debris. Significance: Although all systems caused apical extrusion of debris and irrigant, continuous rotary instrumentation was associated with less extrusion as compared with the use of reciprocating file system.
The paper deals with the traveling wave cylindrical heating systems. The analysis presented is analytical and a multi-layer model using cylindrical geometry is used to obtain the theoretical results. To validate the theoretical results, a practical model is constructed, tested and the results are compared with the theoretical ones. Comparison showed that the adopted analytical method is efficient in describing the performance of such induction heating systems.
Abstract-Servo motors are important parts of industry automation due to their several advantages such as cost and energy efficiency, simple design, and flexibility. However, the position control of the servo motor is a difficult task because of different factors of external disturbances, nonlinearities, and uncertainties. To tackle these challenges, an adaptive integral sliding mode control (AISMC) is proposed, in which a novel bidirectional adaptive law is constructed to reduce the control chattering. The proposed control has three steps to be designed. Firstly, a full-order integral sliding manifold is designed to improve the servo motor position tracking performance, in which the reaching phase is eliminated to achieve the invariance of
... Show MoreBACKGROUND: Vaccine hesitancy and reluctant had an important obstacle in achieving protection and population immunity against coronavirus disease 19 (COVID-19). It is essential to achieve high COVID-19 vaccination acceptance rates among medical students and health care workers to provide recommendations and counseling vaccine hesitant population. AIM: This study aims to identify level of COVID-19 hesitancy, attitude, knowledge, and factors that affect vaccination decision. MATERIALS AND METHODS: A cross-sectional study was done among medical students in Al-Kindy College of Medicine, University of Baghdad, Baghdad, Iraq. Data collection was done through an online Google Forms questionnaire during 2021 from 810 medical students.
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This study cares for the economic living conditions in Mosul City. Its importance lies in the critical period that has been covered
(2002-2007), which was dominated by far–reaching events at political economic and social levels. Among the main results that have been revealed are the following: the rate of economic growth in the City has been the lowest among major urban centers in Iraq. Besides, real income per capita in the City has stayed stagnant during the period of the study. However, the inequality in distribution of income has decreased. The main bulk of the city's population rely on their income from wages and salari
AlPO4 solid acid catalyst was prepared in order to use it in transesterification reaction of edible oil after supporting it with tungsten oxide. The maximum conversion of edible oil was obtained 78.78% at catalyst concentration (5gm.), temperature 70°Ϲ, 30/1 methanol/edible oil molar ratio, and time 5hr. The study of kinetics of the transesterification reaction of edible oil indicates that the reaction has an order of 3/2, while the value of activation energy for transesterification reaction is 51.367 kJ/mole and frequency factor equal 26219.13(L/ mol.minute).
AlPO4 solid acid catalyst was prepared in order to use it in transesterification reaction of edible oil after supporting it with tungsten oxide. The maximum conversion of edible oil was obtained 78.78% at catalyst concentration (5gm.), temperature 70°Ϲ, 30/1 methanol/edible oil molar ratio, and time 5hr. The study of kinetics of the transesterification reaction of edible oil indicates that the reaction has an order of 3/2, while the value of activation energy for transesterification reaction is 51.367 kJ/mole and frequency factor equal 26219.13(L/ mol.minute).
Herein, a cost-effective bio approach using extract derived from desert truffles (Tirmania nivea) is utilized to synthesize gold nanoparticles (AuNPs). AuNPs were thoroughly investigated using UV–vis, XRD, SEM, and TEM analyses. It was shown that nanoparticles had an fcc structure with a smooth spherical surface, an average diameter of 9.44 ± 0.26 nm, and an SPR band observed at 548 nm. Investigations were conducted on AuNPs' antibacterial and anti-cancer properties of prostate cancer cells. The findings suggest that AuNPs showed better antibacterial effects against S. aureus compared to E. coli, P. aeruginosa, and K. pneumoniae. AuNPs’ combination with antibiotics demonstrated a synergistic effect with significant antibacterial activi
... Show MoreThis study aimed at accounting for the role of talents management in consolidating organizational learning process at the Yemeni General Corporation For telecommunication. To achieve the objective of the study, the researcher designed a questionnaire and administered it. The sample of the study consisted of (166) employees (General Manager, Manager and Department Head). They were selected randomly out of a total Population of (291) employees during the Year 2019. The descriptive analytic approach was used t reach conclusions.
The finding of the study revealed existence of effect of talents management dimensions, all together and alone, (talents polarization, talents development, talents maintenance and ma
... Show MoreThe present study was investigated the activity of aqueous extract from Cinnamomum cassia bark on the blood glucose levels in healthy and diabetic rats induced by Streptozotcin (STZ). In healthy rats the blood glucose levels were slightly decreased after six hoursof single oral administration with dose (25 mg/kg) of body wight, as well as four weeks after twice daily repeated oral administration of aqueous extract of Cinnamomum cassia bark. In streptozotocin induced diabetic rats we absorved high significant decreased (p<0.05) in blood glucose levels, after four weeks of oral administration of aqueous extract (25 mg /kg ).And blood glucose levels seems to be normal after the period of treatment .Glibenclamide used as standard drug to com
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