1,721,006 research outputs found
Biocontrol of Rust Fungi by Cladosporium tenuissimum
This chapter examines whether Cladosporium
tenuissimum Cooke, a destructive
hyperparasite of rust spores, can be
exploited as a BCA of rust fungi. It reports on
tests carried out to evaluate C. tenuissimum
effectiveness against rusts in the genera
Melampsora, Cronartium, Peridermium,
Uromyces and Puccinia, focusing on its
modes of action, the fine-level analysis of
the fungal host–hyperparasite interface, the
antifungal compounds it produces, and its
ability to reduce disease, both in vitro and in
planta. Since effective biological control is
impossible without due consideration of the
ecology of the BCA, as well as of the other
partners involved, and an examination of
their spatial relationships and interaction
with the environment, attention is also paid
to the biological nature of the fungus,
in particular to those characteristics that
enable it to survive in natural habitats and
retain activity under varying environmental
conditions
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
We 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
Hystological studies on the mycoparasitism of Cladosporium tenuissimum and urediniospores of Uromyces appendiculatus
Interactions between the mycoparasite Cladosporium tenuissimum and the bean rust Uromyces appendiculatus were
studied through light and electron microscopy in vitro at the host–parasite interface. Urediniospore germination
decreased on contact with ungerminated C. tenuissimum conidia, possibly due to antibiosis mechanisms. C. tenuissimum
grew towards the bean rust spores and coiled around their germ tubes. Penetration of the urediniospores occurred either
enzymatically and/or mechanically, through appressorium or infection cushion structures, from which a thin penetrating
hypha was generated. Enzyme production by the mycoparasite was suggested by the loosening of the matricial
components of the spore wall, which sometimes left chitin fibrils visible. Mycoparasite hyphae grew within the host
spore, emptied its content, and emerged profusely forming conidiophores and conidia. C. tenuissimum was able to grow
on media containing laminarin, suggesting the ability of producing glucanases, but not when chitin was used as the sole
carbon source. Conidia that had been grown on a sugar-rich medium, filtered, and extracted with organic solvents, were
found to contain cladosporol and related compounds. Complete control of the bean rust disease was achieved by
application of C. tenuissimum culture filtrates but not by conidial suspensions. This is the first report of parasitism by
C. tenuissimum on U. appendiculatus. These investigations provide additional observations on a genus besides
Melampsora and Cronartium from which this fungus has been isolated and tested to date. The possible role of
environmental factors for the exploitation of this organism as a biocontrol agent is also mentioned
koamabayili/VECTRON-author-checklist: VECTRON author checklist
We 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
- …
