Background: Crown preparation of vital teeth involve the removal of a sound tooth structure, and when enamel removed this lead to exposed dentin with an   increase in the number of open dentinal tubules also the diameter of dentinal tubules will increase, furthermore lead to increase movement of fluids inside the tubules all that causes post preparation sensitivity. The aim of this study is to evaluate the effect of desensitizing by Er:Cr:YSGG laser on shear bond strength of prepared tooth and resin cement. Materials and methods: Thirty sound maxillary premolars, grouped into three groups(n=10). Group A is the control group, group B irradiated by Er:Cr:YSGG laser with (0.25 W, 20 Hz, 1

The voice lesson inherited from the sound explanation of the phenomenon of the realization of Hamza or ease, but an explanation based on the description of the phenomenon rather than research in the voice relations that govern the emergence of the investigation or mitigation, and this is contrary to the lesson of modern voice what the applicants in this regard. This research reveals the differences between the ancients and modernists in the vocal explanation of a variety of patterns of the phenomenon of the realization of Hamza. And the many issues of Hamza realized or diluted we stand in our research when the voice explanation for one of them is to achieve the Hamzah Almtalp of the millennium, and this heart acknowledged by the ancients

The 3-parameter Weibull distribution is used as a model for failure since this distribution is proper when the failure rate somewhat high in starting operation and these rates will be decreased with increasing time .

In practical side a comparison was made between (Shrinkage and Maximum likelihood) Estimators for parameter and reliability function using simulation , we conclude that the Shrinkage estimators for parameters are better than maximum likelihood estimators but the maximum likelihood estimator for reliability function is the better using statistical measures (MAPE)and (MSE) and for different sample sizes.

Note:- n_s : small sample ; n_m=median sample

     In the present investigation two different types of fiber reinforced polymer composites were prepared by hand lay-up method using three different parameters (curing temperature, pressing load and fiber volume fraction). These composites were prepared from the polyester resin as the matrix material reinforced with glass fibers as first group of samples and mat Kevlar fibers as the second group, both with different volume fractions (4%, 8%, and 12%) of fibers. They were then tested by tensile strength and impact strength. The main objective in this study is to use Taguchi method for predicting the better parameters that give the better tensile and impact strength to the composites, and then preparing composites at

Gross domestic product (GDP) is an important measure of the size of the economy's production. Economists use this term to determine the extent of decline and growth in the economies of countries. It is also used to determine the order of countries and compare them to each other. The research aims at describing and analyzing the GDP during the period from 1980 to 2015 and for the public and private sectors and then forecasting GDP in subsequent years until 2025. To achieve this goal, two methods were used: linear and nonlinear regression. The second method in the time series analysis of the Box-Jenkins models and the using of statistical package (Minitab17), (GRETLW32)) to extract the results, and then comparing the two methods, T

This research attempts to dust briefly the concept of deliberativeness in Arabic rhetoric, which was only understood in light of modern Western linguistics, starting with its definition (conformity of speech to the necessity of the case with its eloquence) which contains the elements of the entire creative process as shown by this brief study, in the first chapter that He was labeled (deliberative in Western and Arab thought), and we had started it with deliberation in western thought in the first topic in an attempt to highlight the western concepts of this term so that we could discern its originality in the Arab rhetorical heritage that came next in the second topic (deliberative in Arab thought), explaining the appropriate Th

At the time when many important political events and evolutions took place, the cinema has been pretty active, and witnessed the historical events before and after the two world wars and the cold war. During the first half of the 20th century, the cinema had great interest from the major countries and their politicians, as well as the commercial turnout of large companies to invest in that field for the profits.  In the beginning of the 20th century, the major powers like the Soviet Union, the United States, Germany, Italy, England, and France started to compete in the development of their film industry and the investment of the new medium and the transformation of some famous works of fiction into films that perpetuate their cultur

The aim of the research is to find out the methods of employing the : Infographics in the news sites due to the different communicative roles of the : Infographics . To achieve the research objective, the researcher used the survey method: the method of analyzing the content to analyze the : Infographics material from the selected sample of the news sites. What was said ? And how was it said? Through the design of a content analysis form that includes a number of studied analysis Infographics of the study.

   Receipt date:10/27/2021    accepted date:12/15/2021     Publication date:31/12/2021

        This work is licensed under a Creative Commons Attribution 4.0 International License.

The phenomenon of extremist extremism (terrorism) was one of the most prominent issues that took a large space in the twenty-first century, in which cognitive motives were mixed with strategic and ideological motives, leading to the emergence of terrorist extremi

تتنوع الإمراض التي تدعى بإمراض العصر وتتعقد باستمرار والتوازي مع تقدم البشرية في مجالات التطور العلمي والاجتماعي ومختلف مجالات الحياة الأخرى .

فبالإضافة  إلى الإمراض الفيروسية والعضوية والنفسية هناك مرض تعاطي وإدمان المخدرات (الهاشمي ,  2002  ، ص1).

لم يعد خافيا على احد إن خطر الإدمان على الكحول والمخدرات والمؤثرات العقلية أصبح اليوم يهدد امن وسلامة العديد من دول العالم