1,720,986 research outputs found
The epidemiology of Moraxella catarrhalis
No full textMoraxella catarrhalis is a pathogen of increasing importance and is recognised as one of the most common causes of respiratory tract infection. In particular, it is known for its role in causing otitis media (OM) in children and exacerbation of chronic obstructive pulmonary disease (COPD) in adults. Increasing interest in the development of vaccines against M. catarrhalis necessitates a better understanding of carriage and disease epidemiology; to inform both vaccine development and implementation strategies. To that end a community wide carriage study (the Solent SMART Study) was designed and undertaken to investigate the epidemiology of M. catarrhalis, including risk factors for carriage. As the acquisition of new strains of M. catarrhalis is a known risk factor for exacerbation of COPD, a better understanding of the carriage of M. catarrhalis in those with COPD is of benefit. Care/nursing home residents are a cohort with no prior data related to M. catarrhalis. As a cohort who often suffer from COPD and frequent RTI, there is certainly a need to investigate M. catarrhalis carriage in this vulnerable group. Carriage of M. catarrhalis was therefore investigated in these cohorts of interest. In total 1701 participants were recruited, from which 228 isolates of M. catarrhalis were obtained. In total 8% (CI: 6.7-9.4%) of community-based participants, 19% (CI: 11.0-29.4%) of care/nursing home residents and 4.7% (CI: 1.6-10.7%) of those with COPD carried M. catarrhalis. Carriage site, age, microbial co-carriage, up-to-date vaccination status, recent/concurrent cold and recent use of antibiotics were all significantly associated with the carriage of M. catarrhalis. Antimicrobial resistance was investigated amongst the M. catarrhalis isolated from this study and isolates from disease, providing data which could inform public health strategies. Both carriage and disease isolates showed low levels of resistance, with the most resistance seen for ciprofloxacin. Lastly the prevalence of carriage and AMR over time was investigated using supplementary data from another study. A significant increase in carriage was observed over recent years, however prevalence of AMR remained low with no significant change. This study is important as it provides an insight into the epidemiology of M. catarrhalis, as well as factors that perhaps impact the disease potential of this common pathogen. It also addresses the paucity of data in certain ages and cohorts and helps provide clarity where existing research is inconsistent
Secondary bacterial infections associated with influenza pandemics
No full textLower and upper respiratory infections are the fourth highest cause of global mortality (Lozano et al., 2012). Epidemic and pandemic outbreaks of respiratory infection are a major medical concern, often causing considerable disease and a high death toll, typically over a relatively short period of time. Influenza is a major cause of epidemic and pandemic infection. Bacterial co/secondary infection further increases morbidity and mortality of influenza infection, with Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus reported as the most common causes. With increased antibiotic resistance and vaccine evasion it is important to monitor the epidemiology of pathogens in circulation to inform clinical treatment and development, particularly in the setting of an influenza epidemic/pandemic
Vaccination in Southeast Asia--reducing meningitis, sepsis and pneumonia with new and existing vaccines
No full textStreptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis are leading causes of vaccine-preventable diseases such as meningitis, sepsis and pneumonia. Although there has been much progress in the introduction of vaccines against these pathogens, access to vaccines remains elusive in some countries. This review highlights the current S. pneumoniae, H. influenzae type b, and N. meningitidis immunization schedules in the 10 countries belonging to the Association of Southeast Asian Nations (ASEAN). Epidemiologic studies may be useful for informing vaccine policy in these countries, particularly when determining the cost-effectiveness of introducing new vaccines.</p
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
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