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    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

    Surface roughness and gloss retention of bioactive resin composite after simulated toothbrush abrasion

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    Background. Newly introduced bioactive resin composites are being used more often. Few studies have evaluated the influence of toothbrush abrasion on their surface characteristics. Methods. This study aims to assess the surface roughness (Ra) and gloss values (GU) of 3 bioactive composites and a conventional nanohybrid composite before and after simulated toothbrush abrasion. Five samples each of Filtek Z250 XT, Beautifil Flow Plus, Activa Presto and Predicta Bioactive Bulk were subjected to 10,000 cycles of simulated toothbrush abrasion. Ra and GU values were evaluated at baseline and after each 2,500 cycles. Results. Significant difference was found in both Ra and GU (P 0.05). After 7,500 cycles, the mean Ra value of Activa Presto at 0.64 (0.14) was significantly higher than that of Z250 XT at 0.49 (0.03) (P < 0.001). At 10,000 cycles, Activa Presto had significantly higher Ra at 0.70 (0.10) when compared to Z250 XT at 0.52 (0.08), Beautifil Flow Plus at 0.56 (0.07) and Predicta Bioactive Bulk at 0.59 (0.10) (P < 0.001). Conclusion. All materials showed an increase in Ra and decrease in GU after simulated toothbrushing

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We 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

    Comparative analysis of finishing and polishing procedures on gloss and color stability in bioactive dental resin composites

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    Objective . The aim of this study was to assess the effect of different polishing systems on the color stability of bioactive dental resin composites compared to a conventional composite. Materials and Methods . Two different bioactive dental resin composites (Beautifil Flow Plus F00 and Activa Presto) along with a nanohybrid composite (Filtek Z250 XT) were tested. A total of 20 samples per material were prepared and divided into four groups as per polishing protocol: Sof-Lex Diamond, Jiffy and TorVm polishing systems as well as a control group without polishing. A spectrophotometer was used to measure the color parameters before and after immersion in a coffee solution for 12 days. The color change (ΔE _00 ) was calculated after immersion for each sample. Gloss was also measured at baseline and post immersion using a gloss meter. Results . There was a significant change in both ΔE _00 and gloss in all materials (p < 0.05). Z250 XT exhibited better color stability and gloss retention, particularly with the Jiffy system. Beautifil Flow Plus F00 demonstrated acceptable color stability and high gloss with the TorVm discs. Activa Presto showed significant color changes across all polishing systems. Conclusions . This work highlights the importance of understanding the effect of polishing systems on dental resin composites for optimal aesthetic outcomes. Despite the obvious benefits of bioactivity in both Beautifil Flow Plus F00 and Activa Presto, their performance regarding both color stability and gloss retention was lower than the inert Z250 XT. These findings emphasize the need for careful material and technique selection in clinical practice to ensure the longevity and esthetic quality of dental restorations

    Investigating the impact of whitening toothpastes on bioactive resin-based restorative materials: a comparative analysis

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    Abstract Objective To assess the color stability and surface roughness of bioactive resin-based composite following exposure to coffee staining and brushing with whitening toothpastes. Methods Disk-shaped specimens of Filtek Z250 (FZ), Beautifil Flow Plus (BFP), Activa Presto (AP), and Fuji II LC (FII) were stained with coffee and then brushed with one of three toothpastes, conventional (C-TP), non-peroxide whitening (W-TP) or hydrogen peroxide-containing whitening toothpaste (HPW-TP) for 10 000 cycles. Changes in color (ΔE00) and surface roughness were measured. Results Two-way ANOVA revealed a significant interaction between restorative material and toothpaste type in roughness (p = 0.049) and ΔE00 (p = 0.007). FII consistently had the highest surface roughness change across all toothpastes, and AP showed significantly higher value than BFP and FZ with C-TP and W-TP (p  0.05). Additionally, the effect of toothpaste type on individual parameters, as well as the interaction between material and toothpaste type, was nonsignificant (p > 0.05). Conclusion All materials tested showed increased roughness and unacceptable staining with none returning to baseline color or achieving acceptable color change post toothbrushing, irrespective of toothpaste type. Clinical significance Understanding the effects of staining and whitening toothpastes on bioactive resin-based composites is important for optimizing material selection and maintenance protocols to ensure long-lasting esthetic outcomes in patients prone to staining

    Dispelling the Myths Behind First-author Citation Counts

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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