1,720,964 research outputs found
RFLPtools: Tools To Analyse RFLP Data. R package version 2.0
No full textR Package RFLPtools: Tools to analyse RFLP data. Provides functions to analyse DNA fragment samples (i.e. derived from RFLP-analysis) and standalone BLAST report files (i.e. DNA sequence analysis)
Diversity of the Capnocheirides Rhododendri-Dominated Fungal Community in the Phyllosphere of Rhododendron Ferrugineum L
Full text linkIndividuals of Rhododendron ferrugineum at natural sites within the mountain ranges and valleys Flüela, Julier, Monstein and Grimsel (in the cantons of Graubünden and Bern, Switzerland) were analysed to determine the occurrence of pigmented epifoliar fungi in their phyllosphere. Molecular data from the fungal isolates revealed a wide range of species to be present, forming a well characterized oligospecific community, with Capnocheirides rhododendri (Mycosphaerellaceae, Capnodiales, Ascomycota) being the most frequently occurring taxon. One group of fungi was exclusively isolated from the leaf surfaces and recognized as being residential epifoliar. A second ecological group was absolutely restricted to the inner leaf tissues and considered as truly endofoliar. Members of a third group occurring in both the epifoliar and endofoliar habitats were considered to have an intermediate life habit. Members of this latter group are likely to invade the inner leaf tissues from the outside after having established a mycelium on the leaf surface. Comparison of the degree of pigmentation between cultivated strains of the strictly epifoliar and strictly endofoliar community members provided some indication that epifoliar growth is to a certain degree correlated with the ability of the fungi to develop hyphal pigmentation. The endofoliar growth is assumed to entail a complete lack or presence of a more or less weak hyphal pigmentation
Annuality of Central European deciduous tree leaves delimits community development of epifoliar pigmented fungi
No full textCommunities of dark pigmented epifoliar fungi of various deciduous tree species from habitats in the surroundings of Bayreuth (Upper Franconia, Germany) were compared to those of evergreen plants overwintered in a greenhouse. The fungi were mainly assignable to the genera Aureobasidium, Cladosporium, Alternaria and Phoma, with most plants hosting more than one fungal genotype or taxon. While a host preference was not detected among the fungal taxa, the community composition significantly differed between annual and perennial leaves. The results indicate that the epifoliar fungal community found on leaves of deciduous Central European trees represents an early developmental stage of the same, but further developed community, found on older evergreen leaves. We therefore assume that the life-span of deciduous leaves is too short for the fungal community to reach a steady state
Three new Xylaria species from Southwestern Europe
No full textThree undescribed European species of Xylaria are recognized from new combinations of anamorphic and teleomorphic characters. Their phylogenetic affinities are revealed by a 5.8S/ITS nrDNA analysis. Two of them (X. karsticola and X. vasconica) appear closely related to X. hypoxylon sensu stricto. Xylaria cinerea is distributed in western Europe (France, Spain, United Kingdom) and the Canary Islands and appears closely related to a yet unnamed taxon from New Zealand. In addition to southwestern Europe, X. vasconica is also present in eastern USA. A specimen of X. hypoxylon from the US West Coast agreed with European material with regard to the teleomorph, but its cultures showed a different morphology. Xylaria arbuscula var. plenofissura is reported from a natural habitat on the European mainland for the first time, and the occurrence of this member of the X. arbuscula complex on the Canary Islands is confirmed
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
First fungal community analyses of endophytic ascomycetes associated with Viscum album ssp. austriacum and its host Pinus sylvestris
No full textThe endophytic fungal communities in the hemi-parasitic epiphyte Viscum album and in its phorophyte Pinus sylvestris were compared to reveal the fungal distribution patterns in their hosts. The ITS nrDNA of 208 multiple-isolated fungal strains was sequenced and a newly designed process was applied for assigning taxon names to the obtained sequences. Furthermore, the isolates were grouped as clusters, by subjecting a sequence similarity matrix to various cluster analyses, the results of which were compared and verified by data from phylogenetic reconstructions. In contrast to a previously reported dominance of Leotiomycetes among Pinus inhabiting fungi, the endophytic communities of the two host plant species studied here were dominated by Xylariaceae (Sordariomycetes). This is in accordance with the finding that host selectivity was only a minor factor in explaining the distribution patterns of the endophytic fungi in Viscum and Pinus. Organ and, probably, tissue selectivity had a more pronounced effect. The composition and condition of the woods in the surrounding, however, are concluded to be the major determinants, due to the following circumstantial evidence: The highest similarities in fungal community compositions were found for the leaves of the two host plant species, especially when considering only the older leaves. The finding that the inhabitants of matured or senescent organs are less host-selective is in accordance with decreasing defence capabilities of ageing host plant tissue and an increased nutrient supply for saprobic taxa. Therefore, the composition of the fungal communities in ageing leaves seems to be predominantly ascribed to contagious spread and to depend on the spectrum of nearby sporulating fungal taxa. We suggest that because a broad range of suitable substrates for Xylariaceae was present in immediate vicinity of the study sites, these fungi also dominated among the recorded endophytic taxa
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
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