1,720,976 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
Matrix Metalloproteinase 12 is Critical for Granuloma Formation in the Murine Model of Granulomatous disease
No full textMatrix Metalloproteinase 12 (MMP12) is a protein produced primarily by alveolar macrophages that degrades elastin in the extracellular matrix (ECM) and enables infiltration of immune cells that participate in the inflammatory response. To our knowledge, few studies have been conducted to clarify the role of MMP12 in granulomatous diseases such as sarcoidosis, a chronic inflammatory disease characterized by granuloma formation primarily in the lungs. Previous studies have shown an increase in gene and protein expression of MMP12 in lung tissue and bronchoalveolar lavage (BAL) of patients with sarcoidosis as well as a correlation between MMP12 elevation and disease severity. Our murine model uses multiwall carbon nanotubes (MWCNT) to mimic the characteristics (gene, protein expression, and granuloma formation) observed in sarcoidosis patients. Based on these observations, we hypothesized that MMP12 plays a role in the acute and late inflammatory response in pulmonary sarcoidosis. MMP12KO mice were used to address this hypothesis. Analysis of gene expression of BAL cells in C57BL/6 (wildtype) mice shows a significant elevation in MMP12 after oropharyngeal instillation of MWCNT at all time points (3, 10, 20, 60, 90 days). We observed similar trends in proinflammatory genes chemokine (C-C motif) ligand 2 (CCL2), matrix metalloproteinase 14 (MMP14), and interferon-gamma (IFNÎđ) at all time points and osteopontin (OPN) at 20, 60, and 90 days. MMP12 protein levels increased in BAL cells at all time points. Evaluation of BAL cells from MMP12KO mice shows a similarity in the expression of all proinflammatory genes explored with wildtype at 10 days. CCL2 and MMP14, identified through gene expression profiling of the wildtype to be directly regulated by MMP12, is significantly reduced at 60 days in MMP12KO MWCNT instilled mice compared to wildtype. Histological analyses at 3, 10, 20, and 60 days shows increasing exacerbation in wildtype and continuous attenuation of granuloma formation in MMP12KO mice after exposure to MWCNT. A proposed mechanism for the reduction of granulomas at 60 days in MMP12KO, lead to an investigation into the relationship between MMP12, a pro-inflammatory mediator and PPAR[gamma], an anti-inflammatory modulator. Gene analysis showed a significant increase in MMP12 in PPAR[gamma]KO mice compared to wildtype and a substantial rise in PPARÎđ in MMP12KO mice compared to wildtype. Interestingly, MMP12 significantly increased, and PPAR[gamma] decreased dramatically in African American sarcoid patient's vs. controls when adjusted for race. MMP12 is seemingly instrumental in driving granuloma pathogenesis during inflammation. Evaluation of genes in MMP12KO mice suggests that the macrophage-secreted cytokines and matrix genes explored are necessary for granuloma formation. The significant increase in PPAR[gamma] intrinsically and after instillation with MWCNT in MMP12KO and its' decrease in wildtype mice after MWCNT instillation at 60 days suggests an inverse relationship between MMP12 and PPAR[gamma]. A reduction in granuloma formation in MMP12KO mice compared to wildtype supports a critical role for MMP12 in granuloma formation
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
Peroxisome Proliferator-Activated Receptor Gamma Deficiency Promotes a T Lymphocyte Response in a Murine Model of Chronic Pulmonary Sarcoidosis
No full textSarcoidosis is a chronic granulomatous disease of unknown etiology. Previous studies from our lab have shown a deficiency of the nuclear transcription factor peroxisome proliferator-activated receptor gamma (PPAR[gamma]) in the alveolar macrophages of sarcoidosis patients. We established a murine model of granuloma formation by instillation with multiwall carbon nanotubes (MWCNT), and the expression of PPAR[gamma] was also decreased in MWCNT instilled mice. There is evidence linking lymphocyte reactivity to mycobacterial antigens in sarcoidosis, so we hypothesized that addition of mycobacterial peptide early secretory antigenic target 6 (ESAT-6) to MWCNT might exacerbate the murine T effector cell response. MWCNT with or without ESAT-6 peptide 14 were instilled into macrophage-specific PPAR[gamma]-KO or wild-type mice. Controls received vehicle or ESAT-6 alone. Bronchoalveolar lavage (BAL) fluid was collected for analysis via qPCR, and lymph nodes were collected for histology, qPCR, in vitro studies, or flow cytometric analysis. PPAR[gamma]-KO mice receiving MWCNT+ESAT-6 displayed markedly increased granuloma formation and exhibited mediastinal lymphadenopathy. Additionally, PPAR[gamma]-KO mice treated with MWCNT+ESAT-6 exhibited exacerbated fibrotic severity at 20- and 60- days post-instillation. Similarly, lymphocyte frequency was elevated in the BAL of PPAR[gamma]-KO mice compared to controls at 20- and 60-days post-instillation with MWCNT+ESAT-6. Further, TH17 associated transcription factor ROR[gamma]t and immune regulatory marker PD1 were elevated in PPAR[gamma]-KO mice treated with MWCNT+ESAT-6 compared to sham mice at both time points, with elevation of multiple other TH17 associated genes at 60 days post instillation. Carbon nanotubes were observed in the mediastinal lymph nodes of PPAR[gamma]-KO and wild-type mice post-instillation with MWCNT and MWCNT+ESAT-6, and flow cytometric analyses revealed that CD4+ T cells were significantly elevated in PPAR[gamma]KO mice receiving MWCNT+ESAT-6. These findings suggest that instillation of PPAR[gamma]-KO mice with MWCNT+ESAT-6 elicits an exacerbated granulomatous and T lymphocyte mediated response
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
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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