1,720,980 research outputs found
Clock gene activities, metalloproteinase and TGFβ1 mRNA levels in human dental pulp fibroblasts treated with cyclosporin A
No full textIntroduction. Circadian rhythm of clock gene expression is linked to basic cellular functions and the dysregulation of the endogenous cell circadian time structure is associated with pathological conditions, including extracellular matrix (ECM) disorders. Circadian rhythmicity has been also demonstrated in transcripts that encode for cytokines and enzymes. Cyclosporin A (CsA), an effective immunosuppressive drug, affects ECM components and remodelling, also modifying the metalloproteinases (MMPs) and cytokines such as TGFβ1. Since both ECM and clock genes are important for maintaining normal cell and organ functions, we examined the clock gene expression, the MMPs and TGFβ1 mRNA levels in human dental pulp fibroblast cultures after CsA treatment. Materials and methods. Cells obtained from the dental pulp of three healthy third molars, extracted in 18-year-old orthodontic patients, were grown in culture flasks with 199 medium supplemented with 10% fetal bovine serum (FBS) and antibiotics, at 37°C and 5% CO2. At the 4th passage, fully confluent cultures were treated with 50% FBS for 2 hours and then maintained in 199 medium containing 10% FBS alone or 800 ng/ml CsA for 24 hours. After this time we determined MMP-1, MMP-2, and TGFβ1 mRNA levels by RT-PCR analysis, while Bmal1, Clock, Per1 and Cry1 gene expression by microarray methods. Results and conclusions. The treated dental pulp fibroblasts showed a significant decrease of TGFβ1, and MMP-2 mRNA levels; microarrays showed the inactivation of Bmal1 and the stimulation of Clock gene expression. Since MMP-2 and TGFβ1 are involved in ECM remodelling, and clock genes regulate cell activities and tissue-specific processes, these modifications could affect the normal functions of tissues and organs. Considering that oncologic patients treated by chronomodulated therapy have good responses, the role of changes in circadian cell time structure and ECM turnover in multiple human diseases is an intriguing area for future studies
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
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