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The effect of ER: YAG laser on enamel resistance to caries during orthodontic treatment: An in vitro study
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Background: One common undesirable side effect of orthodontic treatment with fixed appliances is the development of incipient caries lesions around brackets, particularly in patients with poor oral hygiene. Different methods have been used to prevent demineralization; the recent effort to improve the resistance against the demineralization is by the application of lasers. Materials and method: Thirty human premolars extracted for orthodontic purposes were used to test the effect of two energy level of ER-YAG laser on enamel resistance to demineralization. The brackets were bonded on the teeth and all the labial surface excluding 2 mm area gingival to the brackets were painted with acid resistance varnish. Three groups were generated. The first group was the control group (A), with no treatment was performed. In group II (B)and groups III (C); teeth were irradiated by ER-YAG laser of 200, 60 mj energy respectively. All the teeth were individually subjected to acid challenge cycle for 30 days. After debonding longitudinal sections were taken and examined under stereomicroscope. The enamel demineralization evaluation was done by taking the average of three depths at the centre of the artificial lesion. Also the enamel surface was classified by an experienced investigator according to acid etch pattern. Comparisons of the average depth values of the groups were performed with ANOVA and LSD tests. The statistical significance level was set at p ≤ 0.05. Results: The results revealed that average lesion depth was significantly deeper at the control group than the laser groups, and its significantly deeper in group (B) 200 mj than in group (C) 60 mj, enamel surfaces showed deeper pits and craters than in control group. Conclusions: the decrease in artificial caries lesion depth associated with use of the two laser energy level support the ER-YAG laser as a tool to increase enamel resistance to demineralization and white spot lesion prevention. Key words: Demineralization, ER-YAG, laser.

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Publication Date
Mon Dec 30 2024
Journal Name
Iraqi Journal Of Science
The Impact of Fear and Anti-Predator Behavior on the Dynamics of Stage-Structure Prey–Predator Model With a Harvesting
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In this paper, an ecological model with stage-structure in prey population, fear, anti-predator and harvesting are suggested. Lotka-Volterra and Holling type II functional responses have been assumed to describe the feeding processes . The local and global stability of steady points of this model are established. Finally, the global dynamics are studied numerically to investigate the influence of the parameters on the solutions of the system, especially the effect of fear and anti-predation.

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Publication Date
Fri Nov 11 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The initiative of the Central Bank of Iraq and its impact on some banking activities provided by private Islamic banks
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Islamic banks are distinguished by providing banking activities that are unique in providing them from the rest of the other types of banks, and these activities are a group of banking services provided by the bank to its customers, whether these banking activities are tangible or intangible. At the same time, it is a source of bank profits, as Islamic banks impose a percentage of Islamic Murabaha on those banking activities , However, these banks have developed new services that they provide with the funds of the Central Bank initiative launched at the beginning of (2016) due to the economic conditions that befell the country due to the (financial security) crisis that the country faced in 2014. To put forward initiatives, and a

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Publication Date
Tue Jun 01 2021
Journal Name
Baghdad Science Journal
The Influence of Different Light Wavelengths on Growth, Enzymes Activity and Photosynthesis of the Marine Microalga Dunaliella parva W.Lerche 1937
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Light is an important factor that influences the growth and photosynthetic efficiency of microalgae; however, little is known about how light intensity together with the wavelength affect the photosynthetic capacity and growth of marine microalgae. In the present study, the growth of the marine green microalga Dunaliella parva was studied and optimized under different light intensities (25 ~ 70 μmol m-2 s-1) and qualities (blue, green, and red) in comparison with white light at 40 μmol m-2 s-1 as a control. The growth was monitored by counting the cell number, pigment content, Chl a, Chl b, and carotenoids concentrations. The optimal growth and highest photosyntheti

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Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
Investigating the Influence of Precursor Concentration on the Photodegradation of Methylene Blue using Biosynthesized ZnO from Pometia pinnata Leaf Extracts
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The ZnO nanoparticles were synthesized at various precursor concentrations i.e. 0.05, 0.1, and 0.5 M by biosynthesis method based on Pometia pinnata Leaf Extracts. Initial nanoparticle concentration influenced the optical bandgap, shape, and structure of nanoparticles. The photodegradation process was carried out under UV illumination. The efficiency of MB degradation was determined by measuring the decrease in MB concentration and by analyzing the optical absorption at 663 nm recorded by UV-Vis spectroscopy. Results showed that the biosynthesized ZnO nanoparticles exhibited efficient photodegradation of MB, with a maximum degradation rate of 80% after 90 minutes of exposure to UV-C light. The study highlights the potential of Pometia pi

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Publication Date
Thu Dec 01 2022
Journal Name
Al-khwarizmi Engineering Journal
The Influence of Support Materials on The Photo-Fenton-like Degradation of Azo Dye Using Continuous Nanoparticles Fixed-bed Column
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This study used a continuous photo-Fenton-like method to remediate textile effluent containing azo dyes especially direct blue 15 dye (DB15). A Eucalyptus leaf extract was used to create iron/copper nanoparticles supported on bentonite for use as catalysts (E@B-Fe/Cu-NPs). Two fixed-bed configurations were studied and compared. The first one involved mixing granular bentonite with E@B-Fe/Cu-NPs (GB- E@B-Fe/Cu-NPs), and the other examined the mixing of E@B-Fe/Cu-NPs with glass beads (glass beads-E@B-Fe/Cu-NPs) and filled to the fixed-bed column. Scanning electron microscopy (SEM), zeta potential, and atomic forces spectroscopy (AFM) techniques were used to characterize the obtained particles (NPs). The effect of flow rate and DB15 concent

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Publication Date
Tue Jan 20 2026
Journal Name
Opción: Revista De Ciencias Humanas Y Sociales, Issn 1012-1587, Nº. 89, 2019
The effectiveness of employing the molecular representation strategy in the development of information Generation skills in the chemistry of second grade students in Intermediate School
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Autoría: Jehan Faris Yousif. Localización: Opción: Revista de Ciencias Humanas y Sociales. Nº. 89, 2019. Artículo de Revista en Dialnet.

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Publication Date
Wed Oct 11 2023
Journal Name
Journal Of Educational And Psychological Researches
The Degree of Student Teachers Acquisition at Sultan Qaboos University in Skills of Teaching Arabic via A Virtual Micro-Teaching Lab Based on their Point of View
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The study aims to investigate the degree of student teachers at Sultan Qaboos University acquired skills in teaching Arabic via a virtual micro-teaching lab, as well as to reveal the difficulties they faced and their development proposals. To do this, the researchers developed a questionnaire divided into four dimensions: planning, implementation, evaluation, and

ethical values for the teaching profession, in addition to two open-ended questions to identify difficulties and suggestions. It was administered to (30) student teachers. The results revealed that the average degree of student-teacher acquisition of skills was high in its four dimensions. It ranged between (39.2) to (82.2), while the overall average was (56.2).

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Publication Date
Mon Dec 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Analysis of the Effects of Aggressive Shot Peening on Fatigue Life of 7075 – T6 Aluminum Alloy
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 For many years controlled shot peening was considered as a surface treatment. It is now clear that the performance of control shot peening in terms of fatigue depends on the balance between its beneficial (compressive residual stress and work hardening) and beneficial effects (surface hardening).

The overall aim of this paper is to study the effects of aggressive shot peening on fatigue life of 7075 – T6 aluminum alloy. The fatigue life reduction factor (LRF) due to the aggressive shot peening was established and empirical relations were proposed to describe the behavior of LRF, roughness and fatigue life. The benefits of shot peering in terms of fatigue life are dependent on the shot peening time (SPT).

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Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Reflection of selection of employee's strategy on human capital/ (Field research at the University of Baghdad)
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Abstract:

This research aims to know the reflection of selection of employees strategy dimensions ( selection of employees strategy standards, procedures selection of employees strategy , efficiency based on a selection of employees strategy) on human capital (knowledge, skills, abilities) in a sample of Lecturers consists of (Deans and assistants and heads of departments) in ( Baghdad University) included nine colleges and university president as total sample size (54), which represent almost 50% of the total research community of 116, was used in the light of the objectives of the research descriptive and analytical approach, has been a resolution main tool for data collection as well as the interview p

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Publication Date
Fri Oct 23 2020
Journal Name
Palarch’s Journal Of Archaeology Of Egypt/egyptology
A Multimodal Discourse Analysis of Visual Images in UNHCR Reports on Displaced Iraqis
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The advent of UNHCR reports has given rise to the uniqueness of its distinctive way of image representation and using semiotic features. So, there are a lot of researches that have investigated UNHCR reports, but no research has examined images in UNHCR reports of displaced Iraqis from a multimodal discourse perspective. The present study suggests that the images are, like language, rich in many potential meanings and are governed by clearly visual grammar structures that can be employed to decode these multiple meanings. Seven images are examined in terms of their representational, interactional and compositional aspects. Depending on the results, this study concludes that the findings support the visual grammar theory and highlight the va

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