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Evaluation of shear bond strength of zirconia to tooth structure after different zirconia surface treatment techniques
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Background: This study aimed to evaluate the effect of zirconia different surface treatments (primer, sandblast with 50μmAl2O3, Er,Cr:YSGG laser) on shear bond strength between zirconia surface and resin cement. Material and methods: Sixty presintered Y-TZP zirconia cylinder specimens (IPS e.max ZirCAD, Ivoclar vivadent) will be fabricated and sintered in high temperature furnace of (1500 C for 8 hours) according to manufacturer’s instructions to the selected size and shape of (5mm. in diameter and 6mm in height). All specimens were ground flat using 600.800.1000.1200, aluminum oxide abrasive paper to obtain a standardized surface roughness. Surface roughness values were then recorded in µm using surface roughness tester (profilometer) to obtain a standardized data base line for all samples. The specimens were then randomly divided into three main groups (n=20); group A: no surface treatment (control group), group B: specimens in this group treated with 50μm Al2O3 and group C: specimens in this group treated with Er,Cr:YSGG laser. Sixty sound human premolars were used in this study, after construction of acrylic blocks, the occlusal surface of the teeth were ground flat, with diamond cutting disk to obtain a flat dentine surface . Prior to cementation of zirconia cylinders to tooth specimens subgroups (A1,B1,C1) will receive a coat of metal/zirconia primer and left to react for three minutes, while the subgroups (A2,B2,C2) were left undisturbed. Bonding surface of zirconia cylinder was then luted with SpeedCEM self adhesive resin cement under a static load of 2Kg. placed on the vertical arm of the surveyor and allowed to auto cure for 4minutes.The final cemented specimens were then stored in distilled water at room temperature for 24hours. All specimens were subjected to shear loading force in a universal testing machine at crosshead speed of 1mm/min. The shear bond strength values were analyzed statistically with one-way ANOVA; the fractured surfaces of zirconia cylinders were examined with a stereo-microscope to observe the failure mode. Results: The air borne-particle of 50μm followed by primer application showed significantly the higher bond strength than other groups. Conclusion : Within the limitation of this study, the results showed that sandblasting the bonding surface of zirconium cylinders with 50μmAl2O3 produced the highest values of shear bond strength , also the use of primer enhanced shear bond strength as well. Keyword: zirconia surface treatments, shear bond strength.

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Publication Date
Thu Jun 25 2020
Journal Name
International Journal Of Drug Delivery Technology
Development and Characterization of Controlled Release Tablets of Candesartan Cilexetil/ β‑Cyclodextrin Inclusion Complex
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Objective: Matrix tablet approach is one of the delivery systems intended for poorly water-soluble drugs, like candesartan cilexetil (CC). CC is a class II drug used for the treatment of hypertension. Methods: Matrix tablets from (F1x to F18z) were prepared in the presence of β‑cyclodextrin. Matrix tablet formulation ensures control release of the drug and higher dissolution by β‑cyclodextrin. Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) were used to study compatibility. Results: The angle of repose determination showed good flow for most of the formulas, besides having good compressibility. Weight variation test for all formulas showed accepted value. Drug content measurement sho

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Publication Date
Wed Apr 01 2020
Journal Name
Brazilian Dental Journal
In Vitro Homeostasis of Rat Oral Epithelial Cell Cultures Following Withdrawal of Periodontal Pathogens
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Abstract Inflammation of periodontal tissues is the consequence of interaction between periodontal pathogens and immune system. This is associated with increased expression of inflammatory cytokines, which may exert destructive effect to the periodontal tissues when released over long period. The aim of this study was to chronologically track the homeostasis of oral keratinocytes following removal of periodontal pathogens. This was done by investigating expression of selected inflammatory markers and integrity of epithelial monolayers in vitro. Rat oral keratinocytes were stimulated with heat-killed Fusobacterium nucleatum and Porphyromonas gingivalis over 7-days then bacteria were washed away and epithelial cells re-cultured for 3-

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Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Histopathology of Metarhizium anisopliae Entomopathogenic fungus Infected Larve of Musca domestica L. (Diptera : Muscidae)
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This study consist of using Metarhizium anisopliae as abioinsecticide against house fly
Musca domestica L. For controlling it biologicaly its Larvae were treated by sprying them
directly and sprying their food with 2.3 × 10
8
conidia / ml of Metarhizium anisopliae .
Infected Larve showed symptoms of slugishness and slow growth. Histopathological study of
the dead Larve showed Conidial adhesion and germ tube penetrations through body wall and
begining of fungus hyphal growth under the body wall and hyphal invasion in haemocoel and
gut.

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Publication Date
Sun Jan 24 2016
Journal Name
Al-academy
The effectiveness of pantomime in development of movement skills for Kindergarten: محمد إسماعيل الطائي
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In order to a chive the aim of the research the researcher chose the (Nebras kindergarten) to be the search sample .the member of the sampleFrom(males and fameless)and the researcher chose the class of(butterfly) as experimental group to do the pantomime consist of(15)males and fameless, and put(singles, senses ,double senses and communal senses)in the binging of the experiment the researcher applied the measurement of(AL Kaswany and other)as(pre_ test)which prepare to measure, the movement skills for kindergarten, the measurement have the validity and reliability to knowledge the difference between the two experiment. The experiment continue from(20/1/201to 20/2/2014)in the end of experiment the researcher applied the measurement of(AL

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Publication Date
Sun Dec 05 2010
Journal Name
Baghdad Science Journal
Effect of parasites on the of digestive system in Iraqi bulbul Pycnonotus lecuotis mesoptamiae
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This study included collecting of 150 specimens of the Iraqi Bird Bulbule Pycnonotus lecuotis mesoptamiae (Pycnotidae , Passeriformes), from the 1st of November 2004 to 30th of October 2005 in the city of Baghdad and its suburbs, in concern of identifying the internal parasite of the digestive tract of these birds and studying the diseases resulted from the infection. The study showed that the bird Bulbule is Parasitized by Four types of Cestodes ,two of them are recorded in this kind of bird in Iraq for the first time ,Paradicranotinae anormalis and Haploparaxis sp. , and the other two are Raillietina tetragona and Allohymenolepsis sp. ,and by two types of Pin Worm(Trematode) that are identified for the first time in the Bird Bulb

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Publication Date
Fri Jan 11 2019
Journal Name
Iraqi Journal Of Physics
Study of starch, sugar blending effect on the biodegradability of (PVA) for packaging applications
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PVA, Starch/PVA, and Starch/PVA/sugar samples of different
concentrations (10, 20, 30 and 40 % wt/wt) were prepared by casting
method. DSC analysis was carried; the results showed only one glass
transition temperature (Tg) for the samples involved, which suggest
that starch/PVA and starch/PVA/sugar blends are miscible. The
miscibility is attributed to the hydrogen bonds between PVA and
starch. This is in a good agreement with (FTIR) results. Tg and Tm
decrease with starch and sugar content compared with that for
(PVA). Systematic decrease in ultimate strength, due to starch and
sugar ratio increase, is attributed to (PVA), which has more hydroxyl
groups that made its ultimate strength higher than that for

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Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
On Existence of Prime K-Tuples Conjecture for Positive Proportion of Admissible K-Tuples
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Number theorists believe that primes play a central role in Number theory and that solving problems related to primes could lead to the resolution of many other unsolved conjectures, including the prime k-tuples conjecture. This paper aims to demonstrate the existence of this conjecture for admissible k-tuples in a positive proportion. The authors achieved this by refining the methods of “Goldston, Pintz and Yildirim” and “James Maynard” for studying bounded gaps between primes and prime k-tuples. These refinements enabled to overcome the previous limitations and restrictions and to show that for a positive proportion of admissible k-tuples, there is the existence of the prime k-tuples conjecture holding for each “k”. The sig

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Publication Date
Sat Dec 31 2011
Journal Name
Al-khwarizmi Engineering Journal
The Estimation of Vibrational Energy of Two Coupled (Welded) Plates Using Statistical Energy Analysis
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This paper deals with a method called Statistical Energy Analysis that can be applied to the mechanical and acoustical systems like buildings, bridges and aircrafts …etc. S.E.A as a tool can be applied to the resonant systems in the circumstances of high frequency or/and complex structure». The parameters of S.E.A such as coupling loss factor, internal loss factor, modal density and input power are clarified in this work ; coupled plate sub-systems and explanations are presented for these parameters. The developed system is assumed to be resonant, conservative, linear and there is an equipartition of energy between all the resonant modes within a given frequency band in a given sub-system. The aim of th

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Publication Date
Thu Nov 01 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Assessment of Asthmatic Patients’ Quality Of Life in Jordan Fadel Hazza' Ali al-Mahameed.*
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Abstract A descriptive study was conducted in Al-Bashir teaching hospital in Amman city from 15th May 2004 to 15th August 2004 , in order to "Assess the adult asthmatic patients’ quality of life (QOL). Objective: This study aimed at identifying the domains of (Environmental, Physical, Daily Living Activity, Drug and Medication, Psychological , and Social), Methodology : A Purposive (Non-Probability) sample of (100) adult asthmatic patients visited the emergency department and outpatient clinic of chest department in Al-bashir hospital .A Questionnaire was constructed for the purpose of the study, and compris

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Publication Date
Fri Sep 22 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Ability of Kaoline Clays in Adsorption of Aniline,P-Nitro Aniline and 0-Toludine
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Adsorption   of   AniLine  and   some   derivatives  from   aqueous. solution  on kaolin  clays surface  was investigated, The isotherms  were of type  S3  d S4  according to Giles Classification.

The   effect   of   introducing  electron   withdrawing  groups   and

electron  donating

Groups   in  the  aromatic  ring  on  the  adsorption  process   has   been investigated   ;  The  results showed  that the  extent  of  adsorption has been increased as a

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