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The effect of reperated firings and surface finishing techniques on lithium disilicate ceramics that formed with CAD/CAM and press technique on flexural strength and surface roughness
No full textKlinik uygulamada seramik restorasyonların bitirme aşamasında oklüzal aşındırmalar veya renk uyumu gibi sebeplerle tekrarlanan fırınlamalar gerekmekte veya klinikte aşındırma sonrası yüzey pürüzsüzlüğünü sağlama amacıyla mekanik parlatma yöntemleri kullanılabilmektedir. Uygulamalar sonrasında yüzey pürüzsüzlüğü ve direnç değerlerinde değişimler söz konusu olabilmektedir. Bu çalışmada tekrarlanan fırınlamalar ve farklı yüzey bitirme yöntemlerinin (glaze ve mekanik polisaj) CAD/CAM ve presleme yoluyla elde edilen lityum disilikat içerikli cam seramiklerin bükülme dayanıklılığı ve yüzey pürüzlülüğü üzerine etkisi araştırılmıştır. Çalışmamızda 80 adet IPS e.max Press HT (Ivoclar Vivadent) ve 80 adet IPS e.max CAD HT (Ivoclar Vivadent) olmak üzere toplamda 160 adet 15 mm çapında ve 1,2 mm kalınlığında lityum disilikat içerikli cam seramik diskler ISO 6872 standardında göre hazırlanmıştır. Örneklere kontrol fırınlaması haricinde, 1., 3. ve 5. defa ek fırınlamalar uygulandıktan sonra grupların yarısına glaze diğer yarısına ise Sof-lex (3M ESPE) ile mekanik bitirme işlemi yapılmıştır. İki farklı materyalden (IPS e.max Press ve IPS e.max CAD), dört farklı fırınlama aşaması (kontrol, 1. ek fırınalama, 3. ek fırınlama, 5. ek fırınlama) ve iki farklı yüzey bitirme işlemi (Glaze ve Sof-Lex) toplamda 16 grup oluşturulmuştur. Çalışmamızda seramiklerin bükülme direncini ölçme amacıyla Universal test cihazında biaksiyal bükülme testi, yüzey pürüzlüğünü ölçme amacıyla ise profilometre kullanılmıştır. İstatistiksel olarak tekrarlı ölçümlerde iki yönlü varyans analizi, gruplar arası karşılaştırmalarda Bağımsız T testi ile veriler p?0,05 anlamlılık düzeyinde değerlendirilmiştir. Biaksiyal bükülme direnci açısından aynı yüzey bitirme işlemi (glaze/mekanik polisaj) uygulanmış IPS e.max Press (Glaze, 377,87 ± 53 MPa; Sof-lex, 337,95 ± 36 MPa) ve IPS e.max CAD (Glaze, 369,52 ± 90 MPa; Sof-lex, 343,17 ± 53 MPa) örneklerin kontrol grupları arsında istatistiksel olarak anlamlı fark bulunamamıştır. Farklı yüzey bitirme işlemi uygulanan IPS e.max Press örneklerin kontrol gruplarında Sof-lex (337,95 ± 36 MPa) yüzey bitirme işleminde biaksiyal bükülme direncinin glaze (377,87 ± 53 MPa) yüzey bitirme işlemi uygulanan örneklerden düşük olduğu bulunmuştur (p<0,05). Tekrarlanan fırınlamalar göz önüne alındığında IPS e.max CAD örneklerde kontrol, 1.,3., ve 5. ek fırınlama gruplarında fark bulunmazken, IPS e.max Press örneklerde hem glaze hem de Sof-lex yüzey bitirme işlemlerinde kontrol ve 1. fırınlama ile 5. ek fırınlamalarda fark olduğu ve ek fırınlamalarda biaksiyal bükülme direncinin azaldığı gözlenmiştir (p<0,05). Sof-lex yüzey bitirme işlemi glaze yöntemi ile kıyaslandığında IPS e.max Press örneklerin tekrarlanan fırınlamalarla bükülme direncinin azalmasına neden olmuştur. Yüzey pürüzlülük değerleri tüm gruplar için 0,03-0,23 µm değerleri arasında bulunmuştur. Bu değerler Press glaze kontrol grubundaki 0.03 µm' luk sapma dışında klinik olarak kabul edilebilir seviyededir. Tekrarlanan fırınlamalar ile yüzey pürüzlülüğü değerleri grupların çoğunda azalmıştır. Sof-lex yüzey bitirme işlemi sonrasında hem IPS e.max Press (3. ve 5. ek fırınlama haricinde) hem de IPS e.max CAD gruplarında glaze yüzey bitirme işlemine göre daha pürüzsüz yüzey elde edilmiştir (p<0,05). Bükülme direnci ile yüzey pürüzlülüğü arasında herhangi bir nağlantı bulunamamıştır.In clinical practice, repeated firings are necassary after occlusal grinding for providing shade harmony or various reasons. And mechanical polishing methods are necessary in order to provide surface roughness, after occlusal grinding. Surface smoothness and flexural strength values may be alter after applications.In this study, the effect of CAD/CAM, repeated firing obtained by pressing method and different finishing techniques (glazing and mechanical polishing) on the flexural strength and surface roughness of lithium disilicate-containing ceramics formed in different ways were investigated. In our study, totally 160 discs including 80 IPS e.max Press HT and 80 IPS e.max CAD HT were prepared according to ISO 6872 that 15 mm diameter and 1,2 mm thikness. Additional firings were applied to samples at 1th, 3th, and 5th times except control firing. Half of the groups were finished with glaze and the other half were finished with mechanical finishing by Sof-lex after glaze finishing. Totally 16 groups were created. Biaxial flexural strength test was applied with Universal test mechine to measure the flexural strength of the ceramic and In order to measure the surface roughness surface roughnes test was performed by profilometer. Statistically two way anova was used for repeated measures comparison between groups and independent samples t test was used for comparison between two groups. And significant level was p?0,05. The biaxial flexural strength of IPS e.max Press and IPS e.max CAD control groups finished with same surface finishing method (glaze/mechanical finishing) did not show significant difference. The biaxial flexural strength of IPS e.max Press control Sof-Lex (337,95 ± 36 MPa) surface finishing group were found lower than glaze (377,87 ± 53 MPa) surface finishing group.The considering all repeated firings although there were no significant differences between control group, 1.,3. and 5. repeated firings groups in IPS e.max CAD samples. There were significant differences both glaze and Sof-Lex surface finishing methods between control groups and 5. repeated firings Groups and also between 1. repeated firings Groups and 5. Repeated firings groups. Beside this lower biaxial flexural strength were observed in 5. Repeated groups p<0,05). When IPS e.max Press Sof-Lex finishing groups compared with IPS e.max Press glaze surface finishing groups, flexural strength reduced with repaeted firings. Surface roughness values were found between 0,03-0,23 µm and clinical acceptable level for all groups. Surface roughness values was found between 0,03-0,23 µm. All surface roughness values of groups could acceptable except IPS e.max Press glaze surface finishing control group that 0,03 µm deviation from clinical acceptable range. Surface roughness values decreased with repeated firings in most of the groups.After procedure of surface finishing smoother surface were obtained in both IPS e.max Press (except 3. And 5. repeated firing groups) and IPS e.max CAD groups (p<0,05). Sof-lex surface finishing procedure caused decrease of biaxial flexural strength in IPS e.max Press samples. There were no correlation between biaxial flexural strength and surface roughness
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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