1,721,093 research outputs found
TB in children
No full textTuberculosis (TB) in childhood is under reported but represents a sentinel event of transmission in the community. Susceptibility to TB is age-dependent with young children at highest risk of disseminated disease. Age-related differences in immune responses to mycobacteria underlie this phenomenon. Since childhood TB tends to be paucibacillary, bacteriological confirmation is more difficult to achieve and accurate diagnosis remains a challenge. Diagnostics include measures of host sensitisation, such as the tuberculin skin test (TST) and interferon-γ release assay (IGRA), but their performance varies between children and adults and in the context of bacille Calmette-Guérin (BCG) vaccination. Therapeutic regimens are based on adult studies but increased doses have recently been recommended by the World Health Organization (WHO), following pharmacokinetic studies in children. TB/ HIV co-infection adds complexity to diagnosis and management, much like in adults. The BCG vaccine is not fully protective and is not recommended for HIV-infected children. New vaccines are currently under investigation, with trials including infants and adolescents.</p
Immunology and pathogenesis of childhood TB
No full textTuberculosis (TB) in children most commonly results from exposure to a household contact with active TB, and represents ongoing transmission of Mycobacterium Tuberculosis (Mtb) in the community.1 Infants and young children have an increased risk of infection following exposure and progress more readily from infection to active TB disease; in the absence of intervention, infants have a 50-60% risk of disease in the first year following infection.2, 3 It could therefore be argued that the determining factor for the higher susceptibility to disease in children is prolonged, intimate contact between the child and the index case, which might lead to a larger inoculum of Mtb. However, there is little evidence to support this assumption, since the mycobacterial load in children is notoriously low, which lies at the root of the problem of bacteriological confirmation of primary TB. Young children more commonly present with disseminated disease and have an increased risk of death.2 Even low bacillary loads in children can lead to acute and severe illness, be it respiratory or disseminated, especially in children younger than 2 years of age. The generally accepted assumption is therefore that qualitative and quantitative differences in the immune responses to Mtb infection between adults and children determine outcome. In the following review, we describe the multiple factors involved in containment of mycobacteria and review potential differences between responses in adults versus children. We have chosen to base this article primarily on studies conducted in the human host and - where available - in children. It is however obvious that crucial data on the impact of age on many of the cited factors are missing from the published literature, and we indicate where further studies would be warranted in this context
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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