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Effect of surface treatments and thermocycling on shear bond strength of various artificial teeth with different denture base materials
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Background: Separation and deboning of artificial teeth from denture bases present a major clinical and labortory problem which affect both the patient and the dentist. The optimal bond strength of artificial teeth with denture base reinforced with nanofillers and flexible denture bases and the effect of thermo cycling should be evaluated. This study was conducted to evaluate and compare the shear bond strength of artificial teeth (acrylic and porcelain) with denture bases reinforced by 5% Zirconium oxide nanofillers and flexible bases under the effect of different surface treatments and thermo cycling and comparing the results with conventional water bath cured denture bases. Material and methods: Two types of artificial teeth; acrylic and porcelain were used and prepared for this study. Five specimens of each tooth type were processed to each denture base materials after the application of different surface treatments; these teeth were bonded to heat polymerized, nano composite resin and flexible denture bases. Specimens were thermo cycled and tested for bond strength until fracture with an Instron universal testing machine. Data were analyzed with analysis of variance and student T-test. Photomicrographic examinations were used to identify adhesive and cohesive failures within debonded specimens. Results: The mean force required to fracture the specimens were obviously larger for nanocomposite specimens compared with the heat cured and flexible specimens. The most common failure was cohesive within the tooth or the denture base. With each base material, the artificial teeth which were treated with thinner exhibited highest shear bond strength. Thermocycling had deleterious effect on the flexible denture base specimens. In general, nanocomposite and heat cured groups failed cohesively within the artificial tooth. While the valplastic groups failed adhesively at the tooth denture base interface. Conclusions: Within the limitations of this study, the type of denture base materials and surface treatments of the tooth selected for use may influence the shear bond strength of the tooth to the base. Selection of more compatible combinations of base and artificial teeth may reduce the number of prosthesis fractures and resultant repairs. Key words: acrylic teeth, porcelain teeth, Nano composite denture base, thermo cycling, flexible denture, thinner,

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Publication Date
Mon Jan 30 2023
Journal Name
Iraqi Journal Of Science
Utilization of Dynamical System on Enfolding Semi-group
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      In this paper, we use  the definition of the action on the set of semi-group of the structure of this research .We introduce the concepts of  -system which is a triple , ,  such that  is a Hausdorff compact space called  phase space,  is a semi-group of transformations with a continuous action  of   on  . We study and proof some theoretical properties related with that system. We also introduce the concept of Enfolding semi-group ( , ,and we prove that it is a compact right topological semi-group. In addition, we study the left and right ideals in the Enfolding semi-group. By using the dynamical system, we reflect various properties concerning with its structure for the Enfolding semi-group. Furthermore, we describe

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Classification of fetal abnormalities based on CTG signal
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The fetal heart rate (FHR) signal processing based on Artificial Neural Networks (ANN),Fuzzy Logic (FL) and frequency domain Discrete Wavelet Transform(DWT) were analysis in order to perform automatic analysis using personal computers. Cardiotocography (CTG) is a primary biophysical method of fetal monitoring. The assessment of the printed CTG traces was based on the visual analysis of patterns that describing the variability of fetal heart rate signal. Fetal heart rate data of pregnant women with pregnancy between 38 and 40 weeks of gestation were studied. The first stage in the system was to convert the cardiotocograghy (CTG) tracing in to digital series so that the system can be analyzed ,while the second stage ,the FHR time series was t

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Publication Date
Wed Dec 30 2015
Journal Name
College Of Islamic Sciences
Doctrinal responses On the fabrications of succor Tamimism
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Doctrinal responses
On the fabrications of succor
Tamimi

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Publication Date
Mon Apr 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On Solution of Nonlinear Singular Boundary Value Problem
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    This paper is devoted to the analysis of nonlinear singular boundary value problems for ordinary differential equations with a singularity of the different kind. We propose semi - analytic technique using two point osculatory interpolation to construct polynomial solution, and discussion behavior of the solution in the neighborhood of the singular points and its numerical approximation. Two examples are presented to demonstrate the applicability and efficiency of the methods. Finally, we discuss behavior of the solution in the neighborhood of the singularity point which appears to perform satisfactorily for singular problems.

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Publication Date
Mon May 15 2023
Journal Name
Iraqi Journal Of Science
Histopathological Effects of Cadmium Chloride on Barbus sharpeyi
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The present study including determined pathological changes in Barbus sharpeyi, as
well as description behavior and growth of bunni fish by used 180 fingerlings, Fish
were distributed randomly upon four treatments in addition to control group. First
treatment (T1) contained cadmium 0.093mg/L with changing water and added cadmium
continuously, the second treatment (T2) contained cadmium 0.093mg/L with changing
water without adding cadmium, third treatment (T3) contained cadmium 0.046mg/L
with changing water and adding cadmium continuously, fourth treatment (T4) contained
cadmium 0.046mg/L with changing water without adding cadmium. In order to estimate
LC50 used 120 fingerlings of fish B. sharpeyi, were exposed to

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Publication Date
Sun Mar 06 2016
Journal Name
Baghdad Science Journal
A Note on the Perturbation of arithmetic expressions
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In this paper we present the theoretical foundation of forward error analysis of numerical algorithms under;• Approximations in "built-in" functions.• Rounding errors in arithmetic floating-point operations.• Perturbations of data.The error analysis is based on linearization method. The fundamental tools of the forward error analysis are system of linear absolute and relative a prior and a posteriori error equations and associated condition numbers constituting optimal of possible cumulative round – off errors. The condition numbers enable simple general, quantitative bounds definitions of numerical stability. The theoretical results have been applied a Gaussian elimination, and have proved to be very effective means of both a prior

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Publication Date
Wed May 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Identification Of Gray Mold On Gerbera jamesonii Plants
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Obviously, within the years  2004, 2005, 2006, several infection cases of  damping – off ,leaves ,flowers ,buds and petioles blight ,stem canker ,crown rot have seen on (Gerbera jamesonii) plants in nurseries and appears  dirty white(brown) color mold at the first and then convert to gray color on the foliage. The studying is carried out in two locations in Baghdad city which are Palestine Street (Al-Khirat, Al-Zina nurseries) and Zaiyuna (Zainab, Zaiyuna, Baghdad nurseries). The isolation and diagnosis were identified the causal pathogen was Botrytis cinerea.The pathogenicity test was carried out with positive results were positive resulted.  The infections percentage on gerbera plants ranged in the studied nu

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Publication Date
Mon Apr 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On SAH – Ideal of BH – Algebra
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     The aim of this investigation is to present the idea of  SAH – ideal , closed SAH – ideal and closed SAH – ideal with respect to an element ,  and s-  of BH – algebra .

We detail and show  theorems which regulate the relationship between these ideas and provide some examples in BH – algebra .

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Publication Date
Fri Jan 26 2024
Journal Name
Iraqi Journal Of Science
On Right (σ,τ)- Derivation of Prime Rings
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Let R be a prime ring and δ a right (σ,τ)-derivation on R. In the present paper we will prove the following results:
First, suppose that R is a prime ring and I a non-zero ideal of R if δ acts as a homomorphism on I then δ=0 on R, and if δ acts an anti- homomorphism on I then either δ=0 on R or R is commutative.
Second, suppose that R is 2-torsion-free prime ring and J a non-zero Jordan ideal and a subring of R, if δ acts as a homomorphism on J then δ=0 on J, and if δ acts an anti- homomorphism on J then either δ=0 on J or J
Z(R).

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
On Solution of Regular Singular Initial Value Problems
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    This paper devoted to the analysis of regular singular initial value problems for ordinary differential equations with a singularity of the first kind , we propose semi - analytic technique using two point osculatory interpolation to construct polynomial solution, and discussion behavior of the solution in the neighborhood of the regular singular points and its numerical approximation, two examples are presented to demonstrate the applicability and efficiency of the methods. Finally , we discuss behavior of the solution in the neighborhood of the singularity point which appears to perform satisfactorily for singular problems.

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