1,721,083 research outputs found
Foot-and-mouth disease sero-surveillance in Africa and vaccine matching
No full textFoot-and-mouth disease virus (FMDV) was the first animal pathogen to be identified as a virus, and today, more than a century later, it remains at the forefront of major animal diseases. It is a very contagious disease and affects cloven-hoofed domestic and wild animals, mostly cattle, swine, sheep, goats and buffaloes. To be able to advice on the best control measures in Africa, information on transmission of FMDV, circulating FMDV topotypes and strains in Africa and how to match vaccines to circulating outbreak virus strains is essential. In this thesis these issues are addressed.
The research work described in this thesis has been performed for three important aspects. The first was to get an overview of the role that animal husbandry, trade and wildlife have on the transmission of FMD virus and to provide a scientific basis for different FMD control measures in Africa. On the same track, two surveillance studies on FMD were carried out to know the level of sero-prevalence and identify the serotypes in cattle in Eritrea. The second was to determine which serological test method is best to be used to test cross-reactions in serology and addresses the inherent variability of the relationship coefficient (r1-value). To this end we analysed the cross-reactions in serology using serum samples from cattle vaccinated with 10 different FMDV serotype A strain vaccines using three serological test methods (virus neutralization test, neutralization index test and the liquid phase blocking ELISA). The third was to investigate whether the formulation of using different adjuvants, antigen composition, antigen payload and administration route of an FMD vaccine had any influence on the breadth of the antibody response in cattle.
The review of reported outbreaks shows that substantial diversity of the circulating FMDV serotypes and topotypes is linked to the complexity of the livestock husbandry system, the marketing structure, and livestock-wildlife interface reflecting the significant influence on the risk of transmission of the virus. The sero-surveillance studies show that serology can give indications of virus circulation not detected by agent surveillance. The comparisons of tests used for antigenic matching shows that the LPB-ELISA is the best test for detecting antigenic differences between FMDV strains. Our study on vaccine formulation and application shows that breadth of the antibody response depends mainly on the vaccine strain; we therefore propose that, for vaccine preparation, only FMD virus strains are selected that, among other important characteristics, will induce a wide antibody response to different field strains.
For Africa control of FMDV by vaccination seems the best option, as control of animal movement will be difficult. Use of broadly cross-protective vaccines for FMD is recommended as variant viruses could be introduced from neighbouring countries/regions.
A vaccination strategy has still a number of challenges, among others vaccine quality control and quality control of the vaccination campaign. We believe that despite the enormous investments needed in the long run, FMDV control in Africa would improve national and regional economies and food security and protect livelihoods
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
Riftdalkoorts kan lang verborgen blijven
No full textRiftdalkoorts komt nu in vrijwel heel Afrika voor. In 2000 dook de ziekte ook op in Jemen en Saoedie-Arabië. Noordelijker is het te koud voor het virus, maar dat is volgens viroloog Rob Moormann geen reden om achterover te leunen. Van blauwtong werd immers ook gedacht dat het in Nederland niet kon overleve
Structure and genetic organization of the rat Ú-crystallin gene family
Get PDFContains fulltext :
mmubn000001_027718441.pdf (Publisher’s version ) (Open Access)Promotor : J. Schoenmakers215 p
Over Vaccinologie en ongenode gasten
No full textExotische infectieziekten veroorzaakt door virussen die vanuit het dier naar de mens worden overgedragen, zogenoemde zoonotische virale aandoeningen, vormen een steeds grotere bedreiging. Daarbij spelen klimaatverandering, insecten, wild, toerisme en handel een belangrijke rol. De succesvolle ontwikkeling en toepassing van (moderne) vaccins bij de bestrijding van dit soort ongenode gasten zal als een rode draad door de oratie van prof.dr. Rob Moormann lopen.
Verder zal hij zich toespitsen op het Rift Valley Fever-virus, veroorzaker van dodelijke infecties in mens en dier (tot nu toe nog vooral in Afrika). Het virus wordt als een belangrijke bedreiging gezien voor onze westerse samenleving ook vanuit het oogpunt van bioterrorisme. En... er zijn geen goede vaccins tegen
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
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