Back ground: This in vitro study was carried out to investigate the effect of post space regions (coronal, middle and apical), Time and the mode of polymerization (dual, self-cured) of the cements used on the bond strength between translucent fiber post and root dentin by using push-out test. Materials and Methods: Forty eight extracted mandibular first premolars (single root) were instrumented with ProTaper Universal system files (for hand use) and obturated with gutta percha for ProTaper and AH26® root canal sealer following the manufacturer instructions, after 24 hours post space was prepared using FRC postec® plus drills no.3 creating 8 mm depth post space. The prepared samples were randomly divided into two main groups (24 samples each) according to the used cement (Group M, self-cure, Multilink N) and (Group R, dual cure, Relyx U100). Then each group was subdivided into three groups (each group contains 8 samples) according to the testing time after cementation. (g M1: push out test after 24 hour of cementation with Multilink N), (g M2: push out test after one week of cementation with Multilink N),(g M3: push out test after two weeks of cementation with Multilink N), (g R1: push out test after 24 hours of cementation with RelyxU100), (g R2: push-out test after one week of cementation with RelyxU100), (g R3: push out test after two weeks of cementation with RelyxU100). After cementation and incubation each root was sectioned horizontally into 3 slices (2 mm in thickness) represent the coronal, middle and apical regions of the post space. Push out bond strength test was performed and measured using a universal testing machine (Tinius-Olsen) at across head speed of 0.5 mm/min. Results: showed that regarding the root region, the bond strength values increased significantly apical to coronal region in both tested cements. For the effect of time, the bond strength values also significantly increased with time for both tested cements. For mode of polymerization, the self-cured resin cement Multilink N showed higher bond strength values. Conclusion: the retention of fiber post was affected by root region, mode of polymerization of the cements used and time elapsed after cementation of the post.
Studied competence spam to malicious moth figs at temperatures and Kagafat host different results showed that female intruder, despite their ability to shell larvae host and when densities of different, but it is able to lay eggs at a temperature of 14 + or -1 and finally urged the efficiency spam to malicious affected heavily host and that the greater the intensity of the host spam increased efficiency and its performance life
A field experiment was carried out in the College of Agricultural Engineering Sciences - University of Baghdad, during the fall season of 2021 to find out which cultivated cultivars of maize are efficient under nitrogen fertilization. The experiment was applied according to an RCBD (split-plot design with three replications). The cultivars of the experiment (Baghdad, 5018, Sarah) supply three levels of nitrogen fertilizer, which are N1 (100 kg.N/ha), N2 (200 kg.N/ha) and N3 (300 kg.N/ha). The statistical analysis results showed the superiority of the Sarah genotype, which gave the highest value of SOD and CAT enzymes, reaching 11.59 units mg-1 and 10.76 units mg-1 . Protein sequentially, while cultivar5018 outperformed as it gave th
... Show More
(14)
(9)
ABSTRACT
Background : The aim of this work is to assess the role of breast sonography and ductography in the evaluation of different causes of nipple discharge.
Methods : The study will be carried out on twenty-five female patients referred to the Radiodiagnosis department at Alexandria Main University Hospital presenting with nipple discharge.
They were divided into two groups:
Group I include 10 patients (40%) with surgically significant nipple discharge who were the patients with unilateral, uniorificial surgically significant colour type nipple discharge .They were investigated by mammography, sonography, and ductography.
Group II include 15 patients
... Show More
(1)
This field experiment was conducted at Research Station B, Department of Horticulture and Landscape Engineering, College of Agricultural Engineering Sciences, University of Baghdad, Jadiriyah during the fall season of 2019-2020 to evaluate the effect of cultivation dates and soil fertilization source on the growth, yield and quality of broccoli. A split plot design within the RCBD design with three replicates was applied as the Max F1 hybrid broccoli seedlings were transferred to the field at two dates 25, Sep. 2019 and 15, Oct. 2019, which were symbolized as A and B, respectively, and occupied at the main plot. After two weeks of cultivation, the soil fertilizers were applied three times during the season in 20 days between each applicati
... Show More
(8)
A numerical and experimentally investigation for two types of winglets (spiroid and blended), which are used to reduce the induced drag caused by the trailing vortices were presented and discussed in this work. The SOLIDWORK 2016 was used to model a rectangular wing geometry of NACA2415 cross-sectional airfoil with blended and spiroid airfoils (2415 and 0012). The steady, incompressible N.S equations with standard (
The work in this paper focuses on the system quality of direct and coherent communication system for two computers. A system quality is represented by Signal to Noise ratio (SNR) and Bit Error Rate (BER). First part of the work includes implementation of direct optical fiber communication system and measure the system quality .The second part of the work include implementation both the( homodyne and heterodyne)coherent optical fiber communication system and measure the system quality . Laser diode 1310 nm wavelength with its drive circuit used in the transmitter circuit . A single mode of 62.11 km optical fiber is selected as transmission medium . A PIN photo detector is used in the receiver circuit. The optical D-coupler was u
... Show More
The Artificial Neural Network methodology is a very important & new subjects that build's the models for Analyzing, Data Evaluation, Forecasting & Controlling without depending on an old model or classic statistic method that describe the behavior of statistic phenomenon, the methodology works by simulating the data to reach a robust optimum model that represent the statistic phenomenon & we can use the model in any time & states, we used the Box-Jenkins (ARMAX) approach for comparing, in this paper depends on the received power to build a robust model for forecasting, analyzing & controlling in the sod power, the received power come from
... Show More
Abstract
In this study, we compare between the autoregressive approximations (Yule-Walker equations, Least Squares , Least Squares ( forward- backword ) and Burg’s (Geometric and Harmonic ) methods, to determine the optimal approximation to the time series generated from the first - order moving Average non-invertible process, and fractionally - integrated noise process, with several values for d (d=0.15,0.25,0.35,0.45) for different sample sizes (small,median,large)for two processes . We depend on figure of merit function which proposed by author Shibata in 1980, to determine the theoretical optimal order according to min
... Show More
We report a method of converting non-conductive plastic surfaces into conductive by plating either copper electroless or copper electroplating -carbon black containing bending Agent onto Perspex plastics . Various approaches have been studied in order to comparing properties of the plated copper for two methods such as scanning electron microscopy (SEM),thickness, roughness, porosity, tensile Strength and elongation. The results show that the surface of electroplating was uniform, compact, and continuous and it had an obvious metallic sheen, while the surface of plated copper for electroless for it had many pores. Also observed that the coating was composed of small cells. Thes
... Show More