1,721,001 research outputs found
Collectins and their role in lung immunity
No full textThe collectins are a small family of secreted glycoproteins that contain C-type lectin domains and collagenous regions. They have an important function in innate immunity, recognizing and binding to microorganisms via sugar arrays on the microbial surface. Their function is to enhance adhesion and phagocytosis of microorganisms by agglutination and opsonization. In the lung, two members of the collectin family, surfactant proteins A and D, are major protein constituents of surfactant. Another collectin, mannan-binding lectin, is also present in the upper airways and buccal cavity and may protect against respiratory infections. Recent work has shown that collectins have roles in resistance to allergy and in the control of apoptosis and clearance of apoptotic macrophage in the lung
Collectins and host defence
No full textThe collectins are a small family of soluble oligomeric proteins containing collagenous regions and C-type lectin domains. They are related in structure and function to complement protein C1q, and to H-, L- and M-ficolins. In humans, the collectins mannose-binding lectin (MBL) and surfactant proteins A and D (SP-A, SP-D) have important roles in innate immunity. MBL occurs mainly in blood plasma and in the upper respiratory tract. It binds to neutral sugar arrays on microorganisms and acts as an opsonin either directly (by binding to cell-surface calreticulin) or indirectly by activating complement. MBL circulates in complex with any of three proteases, named MBL-associated serine proteases (MASPs)-1, -2 and -3. MBL-MASP-2 complexes activate complement, but the role of MBL-MASP-1 and MBL-MASP-3 complexes is not yet known. MBL deficiency occurs at high frequency, and is associated with susceptibility to infection, particularly in infants. SP-A and SP-D are most abundant in the lungs, and also bind to microorganisms and inhaled particulates, mainly by lectin-sugar interactions. They do not activate complement, but act as opsonins and agglutinators, and have additional effects on cellular regulation. Mice deficient in SP-A or SP-D are susceptible to lung infections, and SP-D-deficient mice develop an emphysema-like condition
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
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