1,721,134 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
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
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
Étude des anthocyanes de l’Hibiscus sp
No full textTrès répandues dans le règne végétal, les anthocyanes sont le sujet d'un grand nombre d'études. Celles-ci abordent en général les aspects concernant leur instabilité vis-à-vis des conditions dans lesquelles elles sont employées ou l'effet bénéfique de leur consommation sur certaines pathologies chroniques. Provenant de nombreux types de fruits et légumes comestibles, elles sont extraites en vue de leur utilisation comme colorant alimentaire naturel. C'est ce dernier aspect qui a été le sujet principal de ce travail dont l'objectif était de montrer que les calices d’Hibiscus sabdariffa (H. sabdariffa) pouvaient être utilisés comme matière première pour la fabrication de colorant.
Les deux principaux cultivars provenant du Sénégal présentent des différences significatives du point de vue de leur contenu en anthocyanes sur le plan qualitatif et quantitatif. L'influence des conditions de culture sur la concentration en anthocyanes a été mise en évidence.
Une technique chromatographique a été utilisée pour concentrer les anthocyanes. Les résultats provenant d'expériences faites en batch agité avec une résine macroporeuse ont permis de déterminer les paramètres tels que le temps de contact nécessaire à l'atteinte de l'équilibre, la capacité d'adsorption maximale et de conclure que la résine utilisée avait une capacité d'adsorption élevée pour les anthocyanes.
Suite à la fabrication du colorant, une partie importante de la masse de calices restait inutilisée alors qu'elle contenait encore des substances valorisables. Leur caractérisation a permis de montrer que les résidus des calices d'H. sabdariffa pourraient être valorisés par la production de pectines destinées au marché des additifs alimentaires, d'oligosaccharides à effet prébiotique ou de biocarburants
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
Influence of heterogeneous fermentation conditions on the productive capacity of recombinant Pichia pastoris
Get PDFPichia pastoris is a widely used recombinant protein expression system, so much that to date, more than 500 biomolecules have been synthesized using this yeast, many of which are approved for production and commercialization by the biotechnological industry.
The pAOX1-based expression system (MUT+) is one of the most widely used to produce rProt in both research and industry. Under productive conditions, MUT+ shows a high consumption rate of methanol and oxygen, and the accumulation of methanol can lead to the accumulation of cytotoxic intermediates such as formaldehyde and formate. This converts methanol and oxygen critical variables in the design of an rProt production strategy.
Culture medium heterogeneity is inherent in large-scale bioreactors. The loss of mixing quality yields to the formation of concentration gradients. Consequently, cells face oscillatory culture conditions that may deeply affect their metabolism. Herein, cell response to transient perturbations, namely high methanol concentration combined with hypoxia, has been investigated using a two stirred-tank reactor compartments (STR-STR) scale-down (SD) system and a Pichia pastoris strain expressing the gene encoding enhanced green fluorescent protein (eGFP) under the control of the alcohol oxidase 1 (AOX1) promoter. Cell residence times under transient stressing conditions were calculated based on the typical hydraulic circulation times of bioreactors of tens and hundreds cubic meters. A significant increase in methanol and oxygen uptake rates was observed as the cell residence time was increased. Stressful culture conditions impaired biomass formation and triggered cell flocculation. More importantly, both expression levels of genes under the control of pAOX1 promoter and eGFP specific fluorescence were higher in those oscillatory culture conditions, suggesting that those a priori unfavorable culture conditions in fact benefit to recombinant protein productivity. Flocculent cells were also identified as the most productive as compared to ovoid cells.
It is known that overexpression of the pAOX1 promoter does not always leads to an improvement in rProt productivity, as many bottlenecks can impair the production ability of secreted rProt. For this reason, the production of extracellular Candida antarctica lipase was analyzed using the same configurations of SD systems as with the eGFP-producer strain. Extended cell residence time in microenvironments of high methanol concentration and low oxygen availability that are typically found at the upper part of a large-scale bioreactor near the methanol feeding point, triggers the unfolded protein response (UPR) and thus impairs protein secretion. Methanol/sorbitol co-feeding was shown herein as a means to reduce the UPR response and to restore productivity of the secreted protein
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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