Background: Dimensional changes of acrylic denture bases after polymerization results in need for further adjustments or even ends with technical failure of the finished dentures. The purpose of this study was to estimate the linear dimensional changes for different palatal depths when using multiple investment materials and polymerization techniques. Materials and methods: Ninety upper complete denture bases were constructed for this study. They were divided into two main groups according to the polymerization methods: conventional water bath and experimental autoclave (short and long cycles). Each main group was further subdivided into three subgroups according to the palatal depth (shallow, medium and deep). Furthermore, for each palatal depth; complete denture bases were invested either with dental stone or laboratory silicone. For each upper complete denture, measurements of linear dimensional changes were done by fixation of metallic screws on the tissue surface of the denture base. The distances were measured by using travelling microscope with an accuracy of 0.001 %. The data were statistically analyzed using three way analysis of variance (ANOVA) for three variables, which were (palatal depth, investments and polymerization techniques), LSD test and student T test for comparisons between groups. Results: There were significant improvements in the dimensional accuracy of denture bases cured with autoclave compared with water bath. Also, silicone investments were a successful alternative to stone, study data shows that short autoclave processing with silicone reduces the magnitude of the linear dimensional changes. On the other hand, long autoclave processing and stone investments were better than silicone in reducing dimensional changes. Conclusion: The findings of this study indicates that the use of autoclave processing in acrylic curing is a promising alternative to the conventional water bath and leads to better dimensional stability for the finished dentures in all oral configurations and palatal depths. Also, Silicone is more preferable than stone, although it's not as strong investing materials when compared with stone.
A particle swarm optimization algorithm and neural network like self-tuning PID controller for CSTR system is presented. The scheme of the discrete-time PID control structure is based on neural network and tuned the parameters of the PID controller by using a particle swarm optimization PSO technique as a simple and fast training algorithm. The proposed method has advantage that it is not necessary to use a combined structure of identification and decision because it used PSO. Simulation results show the effectiveness of the proposed adaptive PID neural control algorithm in terms of minimum tracking error and smoothness control signal obtained for non-linear dynamical CSTR system.
Objective: To evaluate nurses' practices toward coronary artery bypass grafting (CABG) patients in the
intensive care units (ICU) and to find out the relationship with some vanables.
Methodology: A purposive sample of (50) staff nurses was selected out of three hospitals for cardiac surgery.
The study instmment consisted of two major sections was constructed. It is based on the review of literature.
First it is concerned with demographic data for nurses; and the second section is observationaL tool (checklist) is
composed of six parts in which there mere (78) items. Reliability and validity of the observational checklist were
determined through the analysis of a pilot study.
Data were collected through the use of the
The aim of this paper is to present the first record of ctenophore species Pleurobrachia pileus (O. F. Müller, 1776) in the coral reef as was recently found in Iraqi marine waters. The specimens were collected from two sites, the first was in Khor Abdullah during May 2015, and the second site was located in the pelagic water of the coral reef area, near the Al-Basrah deep sea crude oil marine loading terminal. Three samples were collected at this site during May 2015, February and March 2018 which showed that P. pileus were present at a densities of 3.0, 2.2 and 0.55 ind./ m3 respectively. The species can affect on the abundance of other zooplankton community through predation.
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A simple straightforward mathematical method has been developed to cluster grid nodes on a boundary segment of an arbitrary geometry that can be fitted by a relevant polynomial. The method of solution is accomplished in two steps. At the first step, the length of the boundary segment is evaluated by using the mean value theorem, then grids are clustered as desired, using relevant linear clustering functions. At the second step, as the coordinates cell nodes have been computed and the incremental distance between each two nodes has been evaluated, the original coordinate of each node is then computed utilizing the same fitted polynomial with the mean value theorem but reversibly.
The method is utilized to predict
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This paper aims at the analytical level to know the security topics that were used with data journalism, and the expression methods used in the statements of the Security Media Cell, as well as to identify the means of clarification used in data journalism. About the Security Media Cell, and the methods preferred by the public in presenting press releases, especially determining the strength of the respondents' attitude towards the data issued by the Security Media Cell. On the Security Media Cell, while the field study included the distribution of a questionnaire to the public of Baghdad Governorate. The study reached several results, the most important of which is the interest of the security media cell in presenting its data in differ
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This study examined the relationship between the reporting lag (the timeliness of corporate financial reporting) and several independent variables: (1) Audit reporting lag,(2)Company Size,(3) Profitability of the company,(4)Company Age,(5) Sector Type.(6)Audit’s Opinion,(7) Market Type,(8) Gearing,(9) Concentration of ownership,(10) Audit Firm Size(11)Profit or Loss Company(12) Companies Listed lag on the PEX. In order to achieve the objectives of the study and testing its hypotheses, the data Obtained through actual data of a financial reports, and based on me
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The Jeribe reservoir in the Jambour Oil Field is a complex and heterogeneous carbonate reservoir characterized by a wide range of permeability variations. Due to limited availability of core plugs in most wells, it becomes crucial to establish correlations between cored wells and apply them to uncored wells for predicting permeability. In recent years, the Flow Zone Indicator (FZI) approach has gained significant applicability for predicting hydraulic flow units (HFUs) and identifying rock types within the reservoir units.
This paper aims to develop a permeability model based on the principles of the Flow Zone Indicator. Analysis of core permeability versus core porosity plot and Reservoir Quality Index (RQI) - Normalized por
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Al-Aziz's book was chosen as a subject for research as it is one of the important books in the Islamic world in general and the Shafi'i school in particular and its author Imam Abdul Karim bin Mohammed bin Abdul Karim Al-Rafi's, who in the doctrine of the jurisprudence has made prominent lines and left behind invaluable scientific treasures in the service of religion. Its importance is summarized as follows:
1. Being an explanation of the book (brief) of the argument of Islam Imam Ghazali (God's mercy), one of the five books adopted in Shafi'i jurisprudence.
2. His work is Imam Abu al-Qasim al-Rafii known for the brilliance of the investigation and the power of weighting in the doctrine.
3. It is considered an encyclopedia in Sh
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