Background: The purpose of this study was to compare regional bond strength at middle and cervical thirds of the root canal among glass fiber-reinforced composite (FRC) endodontic posts cemented with different cements, using the push-out test to compare the performance (retention) of two types of luting cements; polycarboxylate cement and Zinc phosphate cement used to cement translucent fiber post and to compare the result of the push-out test at different storage times;1 week ,1month and 2 months. Materials and methods: Ninety caries-free, recently extracted single-rooted human teeth with straight root canals was used in this study, The root canals were endodontically instrumented at a working length of 0.5 mm from the apex by means of conventional instruments for hand use (Dentsply, Switzerland) up to size 35.then root canal filling was performed followed by post space preparation up to 8mm including cervical and middle one third of root canal then the fiber post was cemented into canal post space then the root was sectioned to get cervical (4 mm in length) and middle (4 mm in length) thirds ,these thirds were examined by push out test to get values of retention of fiber post inside these canal thirds . Results and Conclusions: The results of this study has been showed that there was no significant differences between push out bond strength between fiber post and root at cervical third as compared with middle third when using polycarboxylate cement or Zinc phosphate cement to cement the fiber post to the canal walls and the results showed that there was no significant differences in push out bond strength for polycarboxylate or Zinc phosphate cement after one and two months but there was highly significantly increase in push out bond strength for resin cements used to cement the fiber post to the root canal after one and two months
The search aims to clarify pollution to negative effects on environment and to an increasing in the dangerous polluted materials that discharged out these factories. To make active procedures in order to limit the environmental pollution.
The search problem came from an assumption which has the researched factory is suffering from the lack of applying the international specification ( ISO 14004 ). The research problem assimilated by these questions:
- What is the level or organization in thinking of environmental system according to ISO 14004 .
- What are the requirements used in researched factor
One eighth of the bird species in the world is considered globally threatened; the avifauna of Iraq comprises 409 species and is considered as the major indicator of the health of Iraq’s biological resources. The Iraqi geography falls into five main regions among which is the desert and semi-desert areas which cover much of the country area. Al-Najaf desert is still one of the poorly known regions from the biodiversity point of view. Birds of conservation concern are detected in Al-Najaf desert during 31 field trips to 20 sites conducted from August 2018 to April 2020, (citing literature records, and personal interviews with locals).The factors caused the bird numbers to decline in Al-Najaf desert include hunting and trapping, logging,
... Show MoreAccording to the topics of study, The intensity of the news coverage of the Abu Ghraib scandal and the US soldiers' torture of Iraqi prisoners have become apparent since the scandal was revealed on April 29, 2004 until May 30, 2004 and the period in which the coverage of this scandal had intensified not only in Al-Zaman, but in all newspapers, magazines and other media locally and internationally. And according to a research taken from Al-Zaman magazine that showed great interest in highlighting the event, interpreting it, following up its roots and results, and showing contradictory claims and slogans between the US and Britain, particularly in respecting human rights and the spread of justice, equality and well-being in Iraq specifical
... Show MoreThe paper presents an overview of theoretical aspects of small radio telescope antenna parameters. The basic parameters include antenna beamwidth, antenna gain, aperture efficiency, and antenna temperature. These parameters should be carefully studied since they have vital effects on astronomical radio observations. The simulations of antenna parameters were carried out to assess the capability and the efficiency of small radio telescopes to observe a point source at a specific frequency. Two-dimensional numerical simulations of a uniform circular aperture antenna are implemented at different radii. The small diameter values are chosen to be varied between (1-10) m. This study focuses on a small radio telescope with a diameter of 3 m sin
... Show MoreBackground: acrylic resin denture base consider a common denture base material for its acceptable cost, aesthetic and easy processing but still has disadvantages including easy of fracture and low impact strength. Material and method: The experimental group was prepared by addition of 15% phosphoric acid 2-hydroxyethyl methacrylate ester (PA2HEME) with polymethyl methacrylate monomer; the experimental groups was compared with the control one. The specimens were prepared according to ADA specification No. 12 with dimension 65 mm x 10 mm x2.5 mm (length x width x thickness respectively). The prepared specimens were tested by three-point flexural strength utilizing Instron Universal Testing Machine (WDW, Layree Technology Co.), Shore D hard
... Show MoreThe current study aims to investigate the effect of strategic knowledge management practices on an excellent performance at the Institution of Industrial Development and Research- the Ministry of Iraqi Industry (IDRMII). The present research is designed according to the descriptive method. To achieve the mentioned research objective, the researchers used the questionnaire as the main data collection tool. The research sample was 150 managers who are working at the top and middle management levels. To analyses the data gathered and reaching the results, several statistical techniques were used within AMOS.V25, SPSS.V21Software, This study reached a set of results, the most important of which is the existence of a positive correlat
... Show MoreThe research is concerned with studying the characteristics of Sustainable Architecture and Green Architecture, as a general research methodology related to the specific field of architecture, based on the differentiation between two generic concepts, Sustainability and Greening, to form the framework of the research specific methodology, where both concepts seem to be extremely overlapping for research centers, individuals, and relevant organizations. In this regard, the research tend towards searching their characteristics and to clearly differentiates between the two terms, particularly in architecture, where the research seeks understanding sustainable and green architectures, how they are so close or so far, and the
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