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Silviculture Impacts and Population Genomics of Coniferiporia sulphurascens, the Causal Agent of Laminated Root Rot
No full textWithin the Pacific Northwest, USA, root diseases of conifers are a major forest health concern. These diseases are primarily caused by basidiomycete fungi. These fungal associates play a vital role in carbon sequestration but also have a significant negative economic impact within the timber industry. As a result, research on forest management practices to help mitigate root disease has become an important factor within forest health protection. Two closely related fungal species, Coniferiporia sulphurascens, and Coniferiporia weirii, are the primary causal agents of diseases known as laminated root rot (LRR) and butt rot. Three independent studies were conducted to investigate forest management strategies for LRR and to better understand the population dynamics of these two important forest pathogens. The first study used long-term permanent plots at two different study sites to compare the effects of different thinning treatments and alternate host rotations on tree mortality caused by Coniferiporia sulphurascens. At the first study site, three different thinning prescriptions were applied across ca. 160 hectares within the Siuslaw National Forest, Oregon, USA. The second study site evaluated the effects of five hardwood rotation treatments on subsequent growth and mortality of planted Pseudotsuga menziesii across 14 hectares of privately-owned forest in Columbia County. For both study sites the results were used to assess the accuracy of the Forest Vegetation Simulator (FVS) and the Western Root Disease Model (WRDM). An analysis of variance determined that there was no significant difference on mortality caused by C. sulphurascens among thinning treatments (p = 0.9816). Within the alternate host rotation study, no effect of hardwood rotation on growth or mortality of P. menziesii was detected (p = 0.253 and p = 0.172). The FVS was shown to over predict growth at both the thinning and alternate host study sites. The WRDM was found to predict observed data more accurately. A second study used 64 full genome sequences of C. sulphurascens and a population genomics approach to investigate evolutionary history, population dynamics, and dispersal capabilities of this fungus. The samples originated from five different populations across Oregon and Washington, USA. Results showed more long-distance gene flow and migration between populations than previously reported. In a final study, the full genome of C. weirii was sequenced and annotated to provide a novel draft genome. The total size of the genome was estimated to be 42.2 Mb. The assembly contained 10,351 predicted protein-coding genes. The estimated mean gene length of the predicted genes was 1,911 bp. Results from phylogenomic analysis support C. weirii and C. sulphurascens being closely related as previously determined by other studies
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
No full textWe 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
Evaluating and attenuating the risk of Septoria canker in the Septoria musiva-hybrid poplar pathosystem
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Host and Pathogen Contributions to the Populus–Sphaerulina Pathosystem
No full textSphaerulina musiva is a fungal pathogen that causes Septoria leaf spot and stem canker on susceptible Populus species and hybrids. In this thesis, host and pathogen contributions to Septoria stem canker disease were explored through: 1) a greenhouse study associating Septoria stem canker phenotypes with molecular markers from a genetic linkage map of a Populus trichocarpa × Populus deltoides F2 pseudo-backcross population; and 2) the development of a protocol facilitating the genetic transformation of S. musiva by Agrobacterium tumefaciens¬. The QTL study localized a single, significant QTL to Linkage Group 16, consistent with currently unpublished reports (Simon et al., unpublished). Additionally, evidence (p = 0.417; p = 0.952) was obtained that the segregation of resistant-to-susceptible stem canker disease severity was not significantly different from the expected 1:1 ratio, supporting the hypothesis that Septoria stem canker resistance is recessive. Genes within a 1000-Kb window centered on the significant marker on Linkage Group 16 were analyzed for indications of positive selection (Ka/Ks > 1) and immune-related gene annotations; several candidate genes are discussed. The second chapter describes the development of a protocol for the genetic transformation of S. musiva through co-cultivation of S. musiva conidia with A. tumefaciens cells carrying a binary vector. Using the methods described, transformants were generated. Evidence supports the conclusion that random insertion of a hygromycin resistance cassette into the genome of S. musiva isolate MN-14 was successful. However, our attempts at gene-disruption transformation (by homologous recombination into a nrps1 gene) appear to have failed, though integration of the hygromycin resistance cassette was detected elsewhere in the genome by PCR. Recommendations for further protocol development are discussed. Finally, the implications of the greenhouse QTL study and S. musiva transformation are explored in consideration of management implications and future research
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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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