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The effect of light curing tip distance on the curing depth of bulk fill resin based composites
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Background: This in vitro study measure and compare the effect of light curing tip distance on the depth of cure by measuring vickers microhardness value on two recently launched bulk fill resin based composites Tetric EvoCeram Bulk Fill and Surefil SDR Flow with 4 mm thickness in comparison to Filtek Z250 Universal Restorative with 2 mm thickness. In addition, measure and compare the bottom to top microhardness ratio with different light curing tip distances. Materials and Method: One hundred fifty composite specimens were obtained from two cylindrical plastic molds the first one for bulk fill composites (Tetric EvoCeram Bulk Fill and Surefil SDR Flow) with 4 mm diameter and 4 mm depth, the second one for Filtek Z250 Universal Restorative with 4 mm diameter and 2 mm depth. Each spcimen was light-cured using WOODPECKER LED CURING LIGHT for 20 sec. Polymerization was performed with the light tip positioned in direct contact, 2 mm, 4 mm, 6 mm and 8 mm distant from the top surface of the sample. After one day of storage in distilled water in a light proof container at 37ËšC, the hardness on the bottom and top surfaces of each specimen was tested using the Digital Micro Vickers Hardness Tester. Then the Data were analyzed statistically by ANOVA test, LSD test and t-test. Results: All experimental groups show top microhardness higher than bottom microhardness with high significant difference with all light tip distances. At 0 mm light tip distance all groups give the highest microhardness value. Filtek Z250 Universal Restorative shows accepted bottom to top microhardness ratio at all light tip distances. Surefil SDR Flow shows accepted bottom to top ratio only at 0, 2 and 4mm light tip distances while Tetric EvoCeram Bulk Fill shows the bottom to top microhardness ratio less than the accepted value with all light tip distances. Conclusion: From the results of this study we can conclude that the polymerization of bulk fill composite depends greatly on the distance from light curing tip, Tetric EvoCeram Bulk Fill composite not recommended to be used as bulk fill restoration in deep cavities and need further studies, while Surefil SDR Flow not recommended to be used in deep cavity when curing tip distance (6-8 mm), in addition we can conclude that the thickness of the increments is more important than light curing tip distance.

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Publication Date
Wed Oct 11 2023
Journal Name
Journal Of Educational And Psychological Researches
Measuring the Change in the Impact of the Corona Pandemic Factors on Psychological Sensitivity and Covid-19 Phobia in a Sample of University Students
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The aim of the research is to measure the change in the impact of the factors of the Corona pandemic on psychological sensitivity and COVID-19 phobia in a sample of Bisha University students and to detect the differences in the phobia (phobia) Covid-19 among the sample members in the measurement before the ban and after the ban was opened, in addition to the differences in psychological sensitivity of  The sample has between sizes before and after the spread of the Corona pandemic, as well as the differences in them according to the gender variable (male, female). The researcher relied on the comparative approach. The scale of psychological sensitivity and COVID-19 phobia was applied to a sample of (62) male and female respondents.

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Measure the Impact of global financial crisis on some indicators of the Saudi Arabia's economy using the Mendel-Fleming model for period (1997-2015)
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         The main objective of this study is to measure the Impact of global financial crisis on some indicators of the Saudi Arabia's economy using the Mendel-Fleming model, the importance of the study applied by focusing on the theme of general equilibrium in the face of fluctuations in the global economy. Study used a descriptive approach and the methodology of econometrics to construct the model. Study used Eviews Program for data analysis. The Data was collected from the Saudi Arabian Monetary Agency, for the period (1997-2014).Stationery of the variables was checked by Augmented Dickey-Fuller (ADF) and Phillips Perron (PP) unit roots tests. And also the co-integration

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Publication Date
Sat Feb 22 2020
Journal Name
Journal Of Economics And Administrative Sciences
The impact of time management on the performance of the functional business: Survey study at Al Salam General Company for Communications and Information Technology
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The aim of the research is to know the level of time management application and its impact on the performance of the job, a survey search in the general company for communication and information technology and provide recommendations that help employees to optimize the use of time and improve performance, which is an important element in controlling the various functions of the company. In order to achieve the objectives of the research, the questionnaire was based on two main variables and distributed to a random sample of (44) employees in the company out of (308) employees, thus the proportion of the sample (14%). After collecting the samples from the sample, there are (6) incomplete forms that have been retri

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Measure the effectiveness of the Balanced Scorecard strategic performance management in public institutions of Jordan )An Empirical Study on the Social Security Corporation – Irbid(
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The goal of this research to identify a set of criteria that can be measured on the basis of which the effectiveness of the application of the Balanced Scorecard in the Jordanian Public Institutions in order to identify the basic requirements to ensure the application of balanced performance measures. The study population consisted of the staff of the Public Institution for Social Security - Irbid of directors of departments and heads of departments and administrative staff, was the use of a random sample of (50) an employee and the employee. The questionnaire was used as a tool to collect data, and as a result of subjecting these standards for the field test and the use of statistical analysis tools to the results of the study c

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Publication Date
Sat Jul 27 2024
Journal Name
International Journal Of Economic Perspectives
The impact of strategic leadership on the building of intelligent organizations: A field study of a group of economic institutions in Algeria
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This study aims to highlight the role of strategic leadership in adopting the intelligent organization model. The study was conducted on 7 economic organizations in Algeria. The study population consisted of 354 leaders, of whom a random sample of 176 leaders (managers, department heads, division heads, engineers) was selected. The researcher used a questionnaire as the main tool of the study. Statistical analysis and hypothesis testing were conducted using SEM (Structural Equation Modeling) with the aid of SPSS.v26 and AMOS.v24 software. The study concluded with a set of results, most notably: there is a statistically significant direct positive effect between strategic leadership and building intelligent organizations at a significance le

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Publication Date
Sat Jul 01 2023
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The impact of the financing structure on investment decisions : Applied research in a sample of commercial banks listed in the Iraq Stock Exchange for the period (2011-2020)
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               The research aims to shed light on the financing structure, which is one of the important pillars of financial management in the commercial banking sector, which enhances its financial position through financing its various investments, which is one of the pillars of the successful economy of the commercial banking sector. in which country. The contents of the research variables, which were represented by the independent variable, financing structure, the dependent variable, and investment decisions in commercial banks, which the researcher tried to address, as the research began with a basic variable that depends on diagnosing the impact of the financin

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
The Limnological Effects of River Lesser-Zab on Tigris River, Iraq
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The present study included the physico-chemical parameters of Lesser-Zab river and its effects on Tigris river. Monthly water samples were taken from the two rivers during January to October 1999.There were no signifcant difference in water temperatures. Both rivers were fresh to oligohalin, alkaline and very hard. Close values were determined in total suspended solids in both rivers with little increasing during rainfall period and high discharge. Water was well areated and over saturation was recorded in several occasions. Dissolved oxygen values of Tigris river were influenced by Lesser-Zab. Cations were more dominant than anions in both rivers. In Lesser-Zab, the anions were increased during spring season and declined in summer which t

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Publication Date
Fri Sep 01 2023
Journal Name
Iraqi Journal Of Physics
Influence of NiTi Spring Dimensions and Temperature on the Actuator Properties
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Nitinol (NiTi) is used in many medical applications, including hard tissue replacements, because of its suitable characteristics, including a close elastic modulus to that of bones. Due to the great importance of the mechanical properties of this material in tissue replacements, this work aims to study the hysteresis response in an attempt to explore the ability of the material to remember its previous mechanical state in addition to its ability to withstand stress and to obtain the optimal dimensions and specifications for the manufacturer of NiTi actuators. Stress-strain examination is done in a computational way using a mutable Lagoudas MATLAB code for various coil radii, environment temperatures, and coil lengths. The computational m

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Publication Date
Wed May 01 2019
Journal Name
Journal University Of Kerbala
Histological study on the ovaries of female mice treated by carbamazepine
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The purpose of this study was to examine the association of oral administration of Carbamazepine during pregnancy and the histological changes in the ovaries of mice. Timed-pregnant mice were divided into experimental and control groups. 60 mice in the experimental group received daily oral of 15 mg/kg of carbamazepine via intragastric tube on gestational days 0 to 18. 20 mice were used as control group. They received normal saline via the same route. Dams underwent laparotomy on pregnancy days 13, 15, and 18 and the ovaries were collected. Routine histological processing of the ovaries histology of paraffin sections stained with haemotoxylin and eosin, were conducted. The ovary under the effect of the drug, there was signs of degeneration

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Publication Date
Sat Sep 30 2023
Journal Name
Tikrit Journal Of Administrative And Economic Sciences
The impact of Outward bank transfers on exchange rates in Iraq
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The depreciation of the Iraqi dinar against the US dollar, reaching low levels and causing disruptions in the local markets, has had detrimental effects on individuals and companies, particularly those with limited income and the poor. The local currency approached around 1600 dinars per dollar, after the official exchange rate had stabilized at around 1450 dinars per US dollar. This depreciation in the value of the Iraqi dinar can be attributed to financial speculation among currency traders, which directly affected exchange rates and illicit dollar smuggling operations. Bank transfers are also important alongside financial transactions, especially in light of current economic developments in the 21st century. To prevent currency s

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