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Studying the Radial and Tangential Velocity Components of the Epithelization Healing Post Photorefractive Keratectomy Surgery of the Human Eye
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Photorefractive keratectomy (PRK) is the refractive technique that began with a physical scraping of the epithelial layer of cornea subsequent by laser treatment. Post this procedure to about 48 hours the removed epithelial layer regenerated to protect the eye again. The regeneration process (called re-epithelization) started from the limbus of the cornea toward the central part of it. The re-epithelization mechanism consists of a change in cell density (mitosis) and cell concentration (migration) with a velocity in two directions: radial and tangential. In the present study, an estimation for both radial (responsible for the overlapped layers toward the outward direction of the cornea) and tangential components (contour shape wave from limbus to the center) has been done for the first time, not like the previous studies that always estimate the velocity values of the re-epithelization only. Results showed that the trend shape of both components agrees with the kinematic behaviour of the mitosis and migration, where the maximum cell density fluctuated toward the central part in exponential decay shape. For a healing diameter of 2mm, the maximum redial velocity was 16.85 µm/h, while the maximum tangential velocity was 55.48 µm/h. These two components give a speed of re-epithelization of 58 µm/h which agrees with the biological and practical healing speed measured of 60 µm/h. Estimating these two components will open the way to understand the relationship between the total epithelial layer required and the total healing time to control the medication period for the patient post-surgery.

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Publication Date
Thu Dec 01 2022
Journal Name
Environmental Nanotechnology, Monitoring & Management
Challenges in the implementation of bioremediation processes in petroleum-contaminated soils: A review
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Environmental pollution is regarded as a major problem, and traditional strategies such as chemical or physical remediation are not sufficient to overcome the problems of pollution. Petroleum-contaminated soil results in ecological problems, representing a danger to human health. Bioremediation has received remarkable attention, and it is a procedure that uses a biological agent to remove toxic waste from contaminated soil. This approach is easy to handle, inexpensive, and environmentally friendly; its results are highly satisfactory. Bioremediation is a biodegradation process in which the organic contaminants are completely mineralized to inorganic compounds, carbon dioxide, and water. This review discusses the bioremediation of petroleum-

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Publication Date
Thu Jun 01 2023
Journal Name
Iraqi Journal Of Physics
Effect of Organic / Inorganic Gate Materials on the Organic Field-Effect Transistors Performance
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The choice of gate dielectric materials is fundamental for organic field effect transistors (OFET), integrated circuits, and several electronic applications. The operation of the OFET depends on two essential parameters: the insulation between the semiconductor layer and the gate electrode and the capacitance of the insulator. In this work, the electrical behavior of a pentacene-based OFET with a top contact / bottom gate was studied. Organic polyvinyl alcohol (PVA) and inorganic hafnium oxide (HfO2) were chosen as gate dielectric materials to lower the operation voltage to achieve the next generation of electronic applications. In this study, the performance of the OFET was studied using monolayer and bilayer gate insulators.

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Publication Date
Thu Aug 31 2023
Journal Name
Iraqi Geological Journal
Biostratigraphy of the Jeribe Formation at Selected Sections in Wasit Governorate, Eastern Iraq
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The present study is concerned with Biostratigraphy of the Early-Middle Miocene outcrops of Jeribe Formation in the Zurbatiyah area, Wasit Governorate, Eastern Iraq. Forty-two Samples collected from Shur Sharin and AL-Hashima outcrop sections. The fossil content is rich in large and small benthic foraminifera; Twenty-one species and genus are identified in this study, in addition to coral, gastropoda, pelecypoda, ostracoda, alge, echinoid and shell fragments. According to the presence of benthic foraminifera, two Biozone have been identified in the Jeribe: Austrotrillina asmariensis-Dendritina rangi Concurrent Zone and Borelis melo curdica range zone.The age of the Formation determined as Early-Middle Miocene depending on these Bioz

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Publication Date
Sun Aug 06 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Measurement Of Organic Concentration in Aldehydes By The Derivative Neutron Activation Analysis Technique
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The aim of this paper is determine the concentration of the organic oxygen in some organic compounds (Aldehydes ) by the derivative neutron activation analysis technique, and the derivative of the oxygen by the nitrogen equivalent toit and the irradiation of anew sample in flounce (1.73*106  n.cm-2.s-1) by the neutron generator .Then the calculation of the radioactivity which is done by using NaI(Tl) . After that we determine the concentration of nitrogen by calibration curve that includes nitrogen compounds which have apparent chemical and physical characteristics .For comparison the result is done by using keldal method.           

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Publication Date
Tue Jan 01 2013
Journal Name
The Education Faculty Journal Of Baghdad University
Analyzing the Rhetorical Structure of Linguistics Dissertation Abstracts Written by Iraqi EFL Graduates
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Publication Date
Mon Dec 05 2022
Journal Name
Baghdad Science Journal
An Asymptotic Analysis of the Gradient Remediability Problem for Disturbed Distributed Linear Systems
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The goal of this work is demonstrating, through the gradient observation of a   of type linear ( -systems), the possibility for reducing the effect of any disturbances (pollution, radiation, infection, etc.) asymptotically, by a suitable choice of related actuators of these systems. Thus, a class of  ( -system) was developed based on finite time  ( -system). Furthermore, definitions and some properties of this concept -system and asymptotically gradient controllable system ( -controllable) were stated and studied. More precisely, asymptotically gradient efficient actuators ensuring the weak asymptotically gradient compensation system ( -system) of known or unknown disturbances are examined. Consequently, under convenient hypo

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Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Improving the Mechanical Properties of Epoxy by Adding Sub-micron Cantaloupe Peel Fibers
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The use of bio-fruit waste has more attention in recent years because of the low cost of bio-fibers and the protection of the environment. In this study, the epoxy was reinforced with fruit residues (cantaloupe peel powder) in proportions (1%, 2%, 3%, 4%, 5%, 7.5%, and 10% by weight) as results of mechanical tests such as impact, hardness, flexural and compression.

Adding sub microns particle size cantaloupe peels particles with a weight ratio of 7.5% improves the epoxy mechanical properties, like impact strength, hardness, flexural strength, and compression strength by 59.43%, 5.8%, 45.7%, and 118.2%, respectively.

Using X-ray diffraction, the crystallite size ( D) of cantaloupe peel the powder was about (3 nm).

In

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Publication Date
Fri Jan 26 2024
Journal Name
Iraqi Journal Of Science
The Dynamics of Holling Type IV Prey Predator Model with Intra- Specific Competition
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In this paper a prey-predator model involving Holling type IV functional response
and intra-specific competition is proposed and analyzed. The local stability analysis of
the system is carried out. The occurrence of a simple Hopf bifurcation is investigated.
The global dynamics of the system is investigated with the help of the Lyapunov
function and poincare-bendixson theorem. Finally, the numerical simulation is used to
study the global dynamical behavior of the system. It is observed that, the system has
either stable point or periodic dynamics.

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Publication Date
Sun Jul 02 2017
Journal Name
Journal Of Educational And Psychological Researches
Complex thinking among secondary school student in accordance with the views of lipman
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The current study has sought to identify the levels of the compound thinking among secondary school students basing and relying on the opinions of Lipman who sees that the compound thinking consists of creative thinking and critical thinking, In accordance with this point of view, researchers have resorted to build scale of the critical thinking in its final form of (28) item additionally to the adoption of Torrance for the creative thinking which was translated by sayed. Khairallah in 1981 after confirming psychometric Properties Of both scales and then collect scores of both scales and be the final score represented the level of the compound thinking that has been shown by the results of secondary school students they have no skill of

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Publication Date
Tue Feb 05 2019
Journal Name
Journal Of The College Of Education For Women
Basic training requirements for teachers from the viewpoint of supervisors in Mafraq Governorate
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This study aimed to reveal the stage for teachers of basic training needs from the perspective of workers in Mafraq Governorate, through a survey of a sample of counselors look at the Ajloun area schools reached (58) counselors.
To achieve the objective of the study was constructed questionnaire where they are finalized (18) items distributed on two dimensions (professional needs, performance requirements) and after confirmation of the validity and reliability have been applied to the sample where the results showed that training needs were high, both on a professional or per formative level .
The results also showed no statistically significant differences in the areas of tool due to gender, educational qualification. The study co

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