Preferred Language
Articles
/
jbcd-707
Early and delayed effect of 2% chlorhexidine on the shear bond strength of composite restorative material to dentin using a total etch adhesive
...Show More Authors

Background: Lack of durability of the bond of the dental adhesive systems to tooth structure is one of the most important problems in tooth colored restorative work. This in vitro study was performed to evaluate the effect of 2% chlorhexidine gluconate(CHX) on dentin bond strength by using total etch adhesive system at twenty-four hours and three months of water storage. Material and methods:A flat dentin surface was prepared for forty sound human maxillary premolar teeth which were acid etched with 36% phosphoric acid gel after being divided randomly into four groups of ten teeth each according to storage time and CHX application, theCHX was applied for 60 seconds before adhesive application for groups I and III which were tested after twenty-four hours and three months respectively, while the distal water was applied for 60 seconds before the application of adhesive for group II and IV which were tested after twenty-four hours and three months respectively.The Prime and Bond® NT™ adhesive (Dentsply) was applied and cured, Composite (Ceram X mono, Dentisply) was applied through special mold with 2 mm thickness and light cured, Then all specimens were stored in distilled water 37oC until the time of testing of each group.Shear bond strength test was performed at the end of the storage period (24 hours or 3 months). Results:T-test results showed high statistically significant reduction in shear bond strength (SBS) in non CHX group IV (tested after 3 months) compared to non CHX group II (tested after 24 hours)(P< 0.01). In CHX groups I (tested after 24 hours) and III (tested after 3 months), results showed no statistically significant differences in shear bond strength(p> 0.05).On the other hand result showed statistically no significant differences between groups I and II in 24 hours shear bond strength (P> 0.05). After 3 months water storage, there was statistically high significant differences between the groups III and IV (P< 0.01). Conclusion: the use of 2 % CHX glocounate solution after acid etching and before bonding of dentin have no adverse effect on immediate bond strength (24 hours storage), and was effective in reducing degradation of resin-dentin bond interface after three months of water storage.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Mar 29 2020
Journal Name
Energy & Fuels
Stable Dispersion of Coal Fines during Hydraulic Fracturing Flowback in Coal Seam Gas Reservoirs—An Experimental Study
...Show More Authors

In subterranean coal seam gas (CSG) reservoirs, massive amounts of small-sized coal fines are released during the production and development stages, especially during hydraulic fracturing stimulation. These coal fines inevitably cause mechanical pump failure and permeability damage due to aggregation and subsequent pore-throat blockage. This aggregation behavior is thus of key importance in CSG production and needs to be minimized. Consequently, such coal fines dispersions need to be stabilized, which can be achieved by the formulation of improved fracturing fluids. Here, we thus systematically investigated the effectiveness of two additives (ethanol, 0.5 wt % and SDBS, 0.001 and 0.01 wt %) on dispersion stability for a wide range of condit

... Show More
Preview PDF
Scopus (92)
Crossref (89)
Scopus Clarivate Crossref
Publication Date
Tue Jun 25 2024
Journal Name
World Academy Of Sciences Journal
Expression of programmed death ligand 1 in patients with triple‑negative breast cancer: Association with clinicopathological parameters
...Show More Authors

The utilization of targeted therapy for programmed death ligand 1 (PD‑L1) has emerged as a prominent focus in contemporary clinical trials, particularly in the context of immune checkpoint inhibitors. The prognostic significance of the expression of PD‑L1 in invasive mammary cancer remains a subject of discussion in clinical oncology, requiring further exploration, despite its recognition as a biomarker for responsiveness to anti‑PDL1 immunotherapy. The present study was conducted to investigate the immunohistological expression of PD‑L1 in women with triple‑negative breast cancer (TNBC), with a particular focus for searching for the associated clinical and pathological characteristics. The present retrospective study examined the

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Journal Of Engineering
Extraction of Manganese Element from Electric Arc Furnace Steel Slag (EAFS) by Liquid-liquid extraction (LLE) method
...Show More Authors

This research investigates manganese (Mn) extraction from Electric Arc Furnace Steel Slag (EAFS) by using the Liquid-liquid extraction (LLE) method. The chemical analysis was done on the slag using X-ray fluorescence, X-ray diffraction, and atomic absorption spectroscopy. This work consisted of two parts: the first was an extensive study of the effect of variables that can affect the leaching process rate for Mn element from slag (reaction time, nitric acid concentration, solid to liquid ratio, and stirring speed), and the second part evaluates the extraction of Mn element from leached solution. The results showed the possibility of leaching  83.5 % of  Mn element from the slag at a temperature of 25°C, nitric acid co

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Aug 01 2015
Journal Name
Journal Of Engineering
An Investigation into Thermal Performance of Closed Wet Cooling Tower for Use with Chilled Ceilings in Buildings
...Show More Authors

Chilled ceilings systems offer potential for overall capital savings. The main aim of the present research is to investigate the thermal performance of the indirect contact closed circuit cooling tower, ICCCCT used with chilled ceiling, to gain a deeper knowledge in this important field of engineering which has been traditionally used in various industrial & HVAC systems. To achieve this study, experimental work were implemented for the ICCCCT use with chilled ceiling. In this study the thermal performances of closed wet cooling tower use with chilled ceiling is experimentally and theoretically investigated. Different experimental tests were conducted by varying the controlling parameters to investigate their effects

... Show More
View Publication Preview PDF
Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
Stand-Alone PV Generator Comparing with Conventional Systems for Electrification of Small Social Centres in Remote Area
...Show More Authors

Many isolated rural communities are located in regions where there is an abundant and reliable supply of solar energy, but where the distance to the nearest power station is many tens or even hundreds of kilometre. It is therefore mainly in these areas that rural electrification is now being provided by PV generators. since Stand-Alone PV generator can offer the most cost-effective and reliable option for providing power needed in remote places. Accordingly these isolated rural canters are fitted with PV for lighting, a refrigerator, a television and socket to supply kitchen appliances

View Publication Preview PDF
Publication Date
Mon Mar 15 2021
Journal Name
Iraqi National Journal Of Nursing Specialties
Impact of Smartphones Addiction upon Primary School Pupil's Achievements at Al-Rusafa Educational Directorate in Baghdad City
...Show More Authors

Objectives: To determine Smartphone addiction among primary school students and its impacts. The samples of the study were240primary school students in derived from stratified random sampling. The questionnaire was used to collect the data. The data were then an- analyzed using correlation statistics. It also caused a negative impact on demic performance of the primary school students.
Methodology: A cross- sectional study in assessment approach in applied in order to achieve the earlier stated objectives. The study was initiated from October 1st, 2019 to April 30th, 2020. Simple random sampling (probability) sample of (240) Pupils study In primary school at Al-Rusafa first directorate schools in Baghdad City.
Results: The study re

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 26 2022
Journal Name
Electrical Engineering
Optimal insulation design of form-wound stator winding with stress grading system under fast rise-time excitation
...Show More Authors

The effective insulation design of the stress grading (SG) system in form-wound stator coils is essential for preventing partial discharges and excessive heat generation under pulse-width modulation excitation. This paper proposes a method to find the optimal insulation design of the SG system aimed at reducing the dielectric and thermal stresses in the machine coil. The non-uniform transmission line model is used to predict the voltage propagation along the overhang, SG, and slot regions considering the variation in the physical properties of the insulation layers. The machine coil parameters for different insulation materials are calculated by using the finite element method. Two optimization algorithms, fmincon and particle swarm optimiz

... Show More
Crossref (1)
Crossref
Publication Date
Tue Jun 21 2022
Journal Name
Peerj Computer Science
Performance evaluation of frequency division duplex (FDD) massive multiple input multiple output (MIMO) under different correlation models
...Show More Authors

Massive multiple-input multiple-output (massive-MIMO) is considered as the key technology to meet the huge demands of data rates in the future wireless communications networks. However, for massive-MIMO systems to realize their maximum potential gain, sufficiently accurate downlink (DL) channel state information (CSI) with low overhead to meet the short coherence time (CT) is required. Therefore, this article aims to overcome the technical challenge of DL CSI estimation in a frequency-division-duplex (FDD) massive-MIMO with short CT considering five different physical correlation models. To this end, the statistical structure of the massive-MIMO channel, which is captured by the physical correlation is exploited to find sufficiently

... Show More
View Publication
Scopus (5)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Mon Jun 15 2020
Journal Name
Al-academy
Manifestations of social isolation in contemporary theater- Socio aesthetic study: صميم حسب الله يحيى -نورس عادل هادي
...Show More Authors

The research presented to the concept of social isolation through the manifestations of that concept and its works within the theatrical presentation space, and the diversity of directing experiences that the theatrical field benefited from, as contemporary data that contributed to the production of theatrical speech engaging with various levels of different form and content, and this was revealed through the chapters of the research that included The first chapter (the systematic framework), the second chapter (theoretical framework), which included the first topic (formations of social isolation), the second topic (social isolation in the world stage), and resulted in indicators including:
1- Postmodernism produced intellectual appr

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Feb 10 2019
Journal Name
Iraqi National Journal Of Nursing Specialties
Assessment of Pregnant Women Knowledge toward Urinary Tract Infection in Primary Health Care Centers at Kirkuk City
...Show More Authors

Abstract
Objective: To assess pregnant women Knowledge toward Urinary Tract Infection at Kirkuk City.


Methodology: A descriptive and analytical study was conducted from 1st of November 2013 and up to the 19 th of August 2014 in five typical primary health care centers at Kirkuk City. A Probability (randomly sample) was used to select the sample of 180 women aged (15-44) years. A questionnaire format was used as a tool for data collection , content validity of the questionnaire achieved through reviewing it by (24) experts in numerous scientific fields and reliability of the questionnaire was determined through a pilot study. Descriptive and inferential statistics were used to analyze the data.

 

Resul

... Show More
View Publication Preview PDF