Abstract: The aim of this study is to assess the effectiveness of 940 nm diode laser in comparison to Endoactivator in elimination of smear layer in terms of radicular dentin permeability and ultra-structural changes of root canal walls by SEM evaluation. Twenty-eight single-rooted extracted lower premolars were instrumented up to size X4 (protaper Next, Dentsaply) and divided into two experimental groups according to the irrigation system, G1; activated by EndoActivator and G2; activated by Diode laser 940 nm, CW mode, 1.7 W. Afterward, the roots were made externally impermeable, filled with 2%methylene blue dye, divided horizontally into three segments representing the apical, middle, and coronal thirds then examined under stereo- microscope. Using analytical software, the root section area and dye penetration area were measured, and then, the percentage of net dye penetration area was calculated. Additionally, scanning electron microscope investigations were accomplished. The non-parametric Mann-Whitney U test was done and showed significant difference between the two experimental groups over the three root thirds and the dye penetration in diode laser group was significantly higher over the whole root length compared to the Endoactivator group. Scanning electron micrographs of diode laser group showed a distinctive removal of smear layer with preservation of the annular structure of dentinal tubules, while EndoActivator group produced uneven removal of smear layer, in efficient cleanliness especially in the apical third.
In this work, ZnO nanostructures for powder ZnO were synthesized by Hydrothermal Method. Size and shape of ZnO nanostructureas can be controlled by change ammonia concentration. In the preparation of ZnO nanostructure, zinc nitrate hexahydrate [Zn(NO3)2·6H2O] was used as a precursor. The structure and morphology of ZnO nanostructure have been characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD). The synthesized ZnO nanostructures have a hexagonal wurtzite structure. Also using Zeta potential and Particle Size Analyzers and size distribution of the ZnO powder
In this paper , some of lexical stylistic , syntactical stylistic devices , and one phonetic stylistic device are going to be illustrated in the study of the aphorisms of “life and death” . These stylistic devices are parallelism , hyperbole , alliteration , meiosis , irony , oxymoron , cliché , litotes , metalepsis , and loose sentences. This paper aims at identifying the functions and the frequencies of these devices. These stylistic devices make one speech and writing more interesting and help to get the attention of readers/ listeners
98 samples were collected from various clinical sources included (Burns, wounds, urines, sputums, blood) From the city of Baghdad, After performing the biochemical and microscopic examination, 52 isolates were obtained for Pseudomonas aeruginosa, 17 (32.7%) isolates from burn infection, 12 (23%) isolates from Wound infection 11 (21.2%) isolates from urine infection, 7 (13.5%) isolates of sputum and 5 (9.6%) isolates from blood. Bacteria susceptibility to form biofilm has been detectedby microtiter plate method, The results showed that 80% of the bacterial isolates were produced the biofilm with different proportions, alg D gene (alginate production) has been detected by polymerase chain reaction (PCR) Which plays an essential role in the fo
... Show MoreThe aim of this study is to calculate the marketing efficiency to measures range of efficiency of the marketing processes of crop and their satisfaction of consumer demand, and calculate the marketing margin in marketing process for stage producer – whole sale and whole sale- retailer stage, and to fulfillment the requirements the research it is aims . The data was collected from 32 farms of tomato from AL-Taji District_Baghdad province Agricultural season 2015 non covered agriculture. The marketing efficiency of sample low 32. 5, and the absolute marketing margin in stage of wholesaler-retailer was 230 I.d/kg, and retailers importance it was 39.36%, although that relative importance of the retailer profits from the marketing
... Show MoreThe study aims to investigate the effectiveness of cognitive-behavioral counseling in reducing symptoms of social anxiety and improving social skills among a sample of intermediate school students in the city of Souq Al-Shuyukh at Dhi Qar Governorate. The sample consisted of (40) female students, their ages ranged (14-15). They were selected based on their high scores on the social anxiety scale. The sample was divided into two groups: an experimental group, and a control group, equal in number (20) students in each group. The researcher used the social anxiety scale and the social skills scale. In addition, he used the cognitive-behavioral counseling program, consisting of (11) counseling sessions, with a rate of (45) minutes per sessio
... Show MoreThe research aims to identify the level of psychological burnout among the professors of Sana’a University in light of the armed conflicts in Yemen. The research sample consisted of (104) faculty members. A descriptive-analytical approach was adopted. The results of the research showed that university professors suffer from psychological burnout at a very high level in the overall score of the scale. There were no statistically significant differences in terms of gender, academic degree, teaching experience, marital status, number of family members, or salary. In light of the results, the researcher presented a number of relevant recommendations and suggestions.
Abstract
The study aims to identify the reality of knowledge management in decision-making in academic departments from the point of view of faculty members at Blonde University. It also aims to propose mechanisms and suggestions to improve decision-making in the academic departments of the university in light of the management of knowledge. To achieve the objectives of the study, a descriptive method was used, in which a questionnaire consisted of (40) items administered to (137) participants of the faculty members. The results of the study indicated that the reality of the application of knowledge management in the decision-making process showed a high score mean. There are no statistically significant d
... Show MoreThe present paper is an experimental study to improve the productivity of the conventional solar still. This done by modifying conventional still in a way that the distilled basin is larger than distillation basin, thus providing an increase in the condensation surface and speeding up the condensation process. Moreover, increase in the dimensions of the distilled base helps coupling reflective panels to the distilled base to reflect incident solar radiation to the distillation basin. For this purpose , two solar stills were made, one conventional designand another made according to the proposed design. The two solar stills were tested during the period from February to July 2009 under varying weather conditions of Basra, Iraq (latitude o
... Show MoreIn this paper, a new equivalent lumped parameter model is proposed for describing the vibration of beams under the moving load effect. Also, an analytical formula for calculating such vibration for low-speed loads is presented. Furthermore, a MATLAB/Simulink model is introduced to give a simple and accurate solution that can be used to design beams subjected to any moving loads, i.e., loads of any magnitude and speed. In general, the proposed Simulink model can be used much easier than the alternative FEM software, which is usually used in designing such beams. The obtained results from the analytical formula and the proposed Simulink model were compared with those obtained from Ansys R19.0, and very good agreement has been shown. I
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