1,720,961 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
A “Splicing Switch” Provides Dual Layers of Regulation of Laminin alpha 3: Implications for Wound Healing and Squamous Cell Carcinoma
No full textThe laminin α3 gene (LAMA3) generates two major isoforms through alternative promoter usage; LAMA3A and LAMA3B. The ratio between these isoforms has been implicated in squamous cell carcinoma (SCC), with an increased LAMA3A:LAMA3B correlating with poor patient survival. Moreover, the proteins produced, laminin α3a and α3b, have been shown to be functionally distinct in terms of their relative abilities to support adhesion and migration. Two additional LAMA3B promoter-driven transcripts were further identified, LAMA3LN1 and LAMA3LN2; at least one of which is translated into a functional protein, LaNt α31. The additional isoforms are generated through a rare form of alternative splicing called intron retention and alternative polyadenylation (IRPA). As such, IRPA can reduce the proportion of the full-length transcript being produced from a gene. We hypothesised that the IRPA events in LAMA3 contribute to LAMA3B regulation and, moreover, the protein produced can influence laminin-regulated cell behaviour, such as adhesion and migration.
Isoform specific qRT-PCR revealed that IRPA is dynamically regulated; and at times, under certain conditions, accounts for up to 50% of all transcripts generated from the LAMA3B promoter. Using a dual colour reporter minigene the mechanisms that regulate the production of one of these isoform were investigated. These studies identified that a weak, but not absent, donor and acceptor splice site are essential for IRPA to occur, and that multiple RNA binding proteins are also likely playing an important role in regulating IRPA.
At the protein level, we generated mouse monoclonal Abs specific to LaNt α31, and investigated the expression across the ocular anterior chamber surface epithelium. Interestingly, this revealed LaNt α31 to be restricted to the basal layer of corneal epithelium with low levels of expression, but enriched in the limbus and conjunctival epithelium, where localisation mirrors that of limbal stem cell-associated proteins. In ex-vivo porcine corneal wound and human limbal explant models, LaNt α31 expression was upregulated during the initial phases of re-epithelialisation and in activated limbal regions, but was re-distributed to the basal epithelium once the wound had fully healed. In cultured epithelial cells, expression of eGFP tagged LaNt α31 led to an increase in cell spreading and a reduction in migration speed. In live analyses of new matrix synthesis, LaNt α31 and LMα3 co-distributed and were deposited together, while immunoprecipitation indicated complex formation. Indirect-immunofluorescence revealed changes to LM332 organisation, where tight clusters were observed; with similar findings observed in the distribution of β4 integrin. Interestingly, these changes correlated with an increase in collagen XVII recruitment to the clustered β4 integrin and an increase in LMα3 processing; together pointing to early hemidesmosome maturation.
Using novel rabbit polyclonal Abs raised against a LMα3b specific peptide, expression of LMα3b was compare to LaNt α31 in head and neck SCC. Interestingly, a reduction in LMα3b expression in tongue and larynx SCC correlated with a large upregulation of LaNt α31 in most cases, suggestive of a “splicing switch” in. To investigate the consequences of this up-regulation, LaNt α31 expression was induced in the breast adenocarcinoma cell lines MCF-7 and MDA-231. Interestingly, LaNt α31 up-regulation did not cause a migration or invasion phenotype on collagen I, but it did influence the way in which MDA-231 cells invade into matrigel. Specifically, LaNt α31 expressing MDA-231 cells invaded less into matrigel, but interestingly, exhibited single cell invasion as opposed to the multi-cellular streaming observed with controls, suggestive of a LM-specific effect.
Together, these data reveal two new ways in which laminin α3 is regulated by IRPA; influencing LAMA3B abundance at the transcript level and influencing laminin organisation at the protein level. These findings have implications for wound healing and SCC
Variations on the Author
Get PDF“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
Get PDFWe 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
Risk factors for corneal epithelial wound healing: Can sex play a role?
No full textPurpose To determine if sex is associated with corneal epithelial wound healing time in patients with persistent corneal epithelial defects (PCEDs). Methods Retrospective case series on patients with PCED from November 2014 to January 2019. Records of 127 patients with diagnosis of PCED were reviewed. Patients with an epithelial defect that lasted more than two weeks in the absence of an active corneal infection were included. Main outcome was corneal epithelial wound healing time. Results 55 patients (29 males) with a mean age of 65.3 +/- 16.5 years were included. No difference was found between female and male patients in terms of risk factors, age, treatment strategies or intervals between visits (median of 15 days in females and 12 days in males; p = 0.24). Median duration of the PCED was 51 days (IQR 32-130), with a median number of 5 clinical visits (IQR 4-8). Female patients had significantly longer healing times (p = 0.004) and a corresponding increase in the number of clinical visits (median of 7 visits vs. 5 clinical visits in males, p = 0.012). Conclusion Results from this study suggest female patients with PCED might have a longer corneal epithelial wound healing duration and may therefore require earlier intervention
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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