1,721,127 research outputs found
Long-term evaluation of autologous extraoral bone grafts as bone substitute in maxillary vertical augmentation: An immunohistochemical study
No full textThe aim of this study was to evaluate calvarial grafts when used as bone substitute for maxillary vertical augmentation prior to dental implantology. Bone specimens were harvested from patients at T0 (time of bone harvesting), 4 months (T1), 6 months (T2) and 15 years (T3) after grafting procedure. Morphostructural analysis and immunohistochemical analyses of boneseialoprotein-2 (BSP2), Collagen I, Vascular endothelial growth factor (VEGF), ERK 1⁄2 and nitride oxide (iNOS) inflammatory protein, expression were carried out. Outcomes from T0 specimens were compared to T1, T2 and T3 samples. In immunohistochemical analysis T1 and T2 samples showed the presence of important remodeling phenomena, with areas of bone resorption and apposition, together with new blood vessel formations. The T3 sample showed morphological features very close to native bone, as shown by the disappearance of welding lines. However, small polygonal cells resembling osteoblasts were close to Havers channels. Immunohistochemical analyses showed a drastic decrease of Collagen expression, at T1 and T2, stabilized at T3, in parallel to BSP2 expression increase, which was, however, considerably reduced at T3. Moreover VEGF angiogenic factor was increased at T2, in respect to T0, T1 and T3 which are quite similar. The highest level of Erk1/2 is evidenced in the T2 sample, basal levels of iNOS, related to inflammatory events is highlighted in T0 and T3, in respect to T1. Thus, autologous calavarial bone grafts seem to be suitable as biomaterial for bone regeneration procedures of the jaws. Moreover, the used protocol could be useful for studying bone substitutes in oral surgery and implantology
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
Government and opposition weighted majority games: an analysis of the italian political situation
No full textDispelling 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
Vascular network organization in posterior atrophic human mandible: a guide for an appropriate surgical approach
No full textBackground: The bone vascularity plays a key role for a successful surgical approach during implant placement on the posterior
atrophic lower jawbone. Although, some very old references are reported on animal studies, to the author best knowledge no
data are present in literature regarding this subject.
Aim/Hypothesis: The aim of this work was to evaluate the vascular arrangement in posterior, edentulous, atrophic mandibular
crests on humans
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
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