Background: This study was formulated to compare the effect of 5%hydrofluoric acid in comparison to 37%phosphoric acid with and without the application of silane on bond strength of composite to porcelain. Materials and Methods: Specimen preparation was divided in to two phases, metal-disks fabrication (8mm-diameter and 4mm-thickness) and ceramic veneering. Thirty two specimens were prepared, sandblasted with 50 μm aluminum oxide, and divided into four groups of eight samples. Groups I and III were etched with 37%phosphoric acid while groups II and IV were etched with 5%hydrofluoric acid; and groups I and II were silaneted while groups III and IV were not. Heliobond, and resin composite were applied to each specimen using a plastic transparent split mold (4mm- diameter and 4mm-height). Specimens were stored in distilled water for 24 hours then thermocycled for 100 cycles. Shear bond strength was determined by a Zwick universal machine at a cross-head speed 5 mm/minute. Results: Mean shear bond strength values were 21.02(group I), 23.31(group II), 4.00(group III), and 18.60(group IV). Paired-t revealed that specimens treated with 5%hydrofluoric acid were significantly higher than those treated with 37%phosphoric acid regardless the use of silane. The use of silane dramatically enhanced the bond strength of composite resin to porcelain for both acids. All specimens treated with 37%phosphoric acid without silane showed adhesive failure, while those treated with 5%hydrofluoric acid showed mostly cohesive failure within ceramic. Conclusion: Silane improved the shear bond strength of composite to ceramic, and hydrofluoric acid performed greater bond strength compared to phosphoric acid.
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Abstract
The Research "Surah At-Talaq between Commentators and Jurists" is summarized in the objectives of the Surah, clarifying the meanings of the verses of the rulings contained therein by mentioning the statements of the commentators, with mentioning the most acceptable of those meanings when a difference arises, explanation of the provisions of the Surah, with a statement of sayings of the four religious schools of Islamic jurisprudence, in summary, due to the narrowness of the place, and the most acceptable of them.
The research addresses (9) topics, which are: the objectives of Surah At-Talaq, prohibition of divorce during menstruation, testifying retract and divorce, irrevocably divo
... Show MoreDespite the development in the fields of communication and informatics, the book remains its distinguished presence and popular popularity as it is the oldest means to obtain knowledge, addressing the vast majority of society in different levels and levels of knowledge and culture. The design of the cover book portal and the structure of semolina semantic including the elements of construction and typography contribute to the activation of the relationship between form and content, and here lies the importance of this relativity and its role in enhancing the communicative dimension of the design of the book cover, and cast a shadow on the promotional and marketing effectiveness. Hence the importance of research, but the prob
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This paper aims to give an overview of acculturation in the literature by means of its explicit definitions, main characteristics, and categorical process. It also foreshadows the significance of acquiring novice culture with particular connection to second language acquisition. Schumann and John Berry underscored acculturation each with its own model of acculturation. In the case of this review, you will realize that Schumann's two main aspects are firmly rooted in berry's model of acculturation as an exclusive description in relation to second language acquisition. Steven Krashen outlined acquiring language from the intellectual and linguistic view of learning, whereas Micheal Long demanded for communication in social perspective. It has
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Honorifics are linguistic expressions which maintain social as well as religious respect to other people. They are linguistic techniques which express politeness to other interlocutors. Semantically speaking, honorifics are of two types: al-Laqab (title) and al-Kuniya (teknonyms) following a specific word order. They form part of the Arab recognitions and are mold into their social and communicative competence.
The study focuses upon religious and regional honorifics which convey deference and respect. It assumes that religious and cultural recognitions play vital roles in formulating and embedding the sense of honorifics. It is hypothesized that Arab people express respect to religious personalitie
... Show MoreBackground: Acute myocardial infarction
(AMI) is one of the most common diagnoses
in hospitalized patients. The stimulus that
initiates the acute inflammatory process in AMI
has not been identified. Conventional risk
factors account only for approximately half of
the patients with clinically apparent
atherosclerosis which can leads to AMI.
Recently a potential link between infectious
agents and atherosclerosis has been suggested
Objective: To find a possible association
between Helicobacter pylori (H. Pylori)
infection and AMI.
Method: We studied the prevalence of antiH. pylori antibodies in 94 patients who were
admitted with the diagnosis of AMI and a
similar number of healthy individuals w
Cilnidipine is a dihydropyridine class of calcium channel blockers, it is classified as a BCS class II drug, characterized by a low oral bioavailability of 13%. Consequently, the utilization of nanoparticle preparation is anticipated to enhance its bioavailability. The objective of the research is to integrate cilnidipine nanoparticles into oral films as a means of enhancing patient adherence. The optimal polymers for producing Cilnidipine films were PVA cold and or HPMC E5 at different concentrations using a casting technique with glycerol as a plasticizer. The Nano suspension-based preparation of Cilnidipine's oral film containing the combination of polymers exhibited a significant enhancement in vitro dissolution, with a percentage excee
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Many image processing and machine learning applications require sufficient image feature selection and representation. This can be achieved by imitating human ability to process visual information. One such ability is that human eyes are much more sensitive to changes in the intensity (luminance) than the color information. In this paper, we present how to exploit luminance information, organized in a pyramid structure, to transfer properties between two images. Two applications are presented to demonstrate the results of using luminance channel in the similarity metric of two images. These are image generation; where a target image is to be generated from a source one, and image colorization; where color information is to be browsed from o
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