1,721,064 research outputs found
Fusarium verticillioides and aspergillus flavus co-occurrence influences plant and fungal transcriptional profiles in maize kernels and in vitro
Get PDFClimate change will increase the co-occurrence of Fusarium verticillioides and Aspergillus flavus, along with their mycotoxins, in European maize. In this study, the expression profiles of two pathogenesis-related (PR) genes and four mycotoxin biosynthetic genes, FUM1 and FUM13, fumonisin pathway, and aflR and aflD, aflatoxin pathway, as well as mycotoxin production, were examined in kernels and in artificial medium after a single inoculation with F. verticillioides or A. flavus or with the two fungi in combination. Different temperature regimes (20, 25 and 30◦ C) over a time-course of 21 days were also considered. In maize kernels, PR genes showed the strongest induction at 25◦ C in the earlier days post inoculation (dpi)with both fungi inoculated singularly. A similar behaviour was maintained with fungi co-occurrence, but with enhanced defence response at 9 dpi under 20◦ C. Regarding FUM genes, in the kernels inoculated with F. verticillioides the maximal transcript levels occurred at 6 dpi at 25◦ C. At this temperature regime, expression values decreased with the co-occurrence of A. flavus, where the highest gene induction was detected at 20◦ C. Similar results were observed in fungi grown in vitro, whilst A. flavus presence determined lower levels of expression along the entire time-course. As concerns afl genes, considering both A. flavus alone and in combination, the most elevated transcript accumulation occurred at 30◦ C during all time-course both in infected kernels and in fungi grown in vitro. Regarding mycotoxin production, no significant differences were found among temperatures for kernel contamination, whereas in vitro the highest production was registered at 25◦ C for aflatoxin B1 and at 20◦ C for fumonisins in the case of single inoculation. In fungal co-occurrence, both mycotoxins resulted reduced at all the temperatures considered compared to the amount produced with single inoculation
TRANSCRIPTIONAL ANALYSIS OF EIGHT MAGIC MAIZE PARENTAL LINES INFECTED WITH FUSARIUM VERTICILLIOIDES
Get PDFMaize (Zea mays L.) is among the most important crops worldwide for food,
feed, biofuels, and industrial applications. Its cultivation faces
significant constraints due to Fusarium species that affect the quality and
quantity of maize products. Among these, Fusarium verticillioides is
responsible for severe diseases including seedling blights, stalk rot, and
ear rot. The impact of the fungus is worsened by the fact that chemical and
agronomic measures used to control Fusarium infection are often
inefficient. Hence, genetic resistance is considered the most reliable
resource to reduce damages caused by F. verticillioides. This study aims to
elucidate the genetic basis of resistance to this fungus in maize. Young
seedlings of eight divergent maize lines, founder of the MAGIC population,
were artificially inoculated with a F. verticillioides strain using the
rolled towel assay method. Total RNA was extracted from both control and
treated samples after 72 hours of artificial inoculation and underwent
paired-end sequenced with Illumina technology. Here we report the use this
large transcriptomic dataset to identify the early transcriptional changes
and the differentially expressed genes (DEGs) involved in fungal infection.
The analysis identified several hundred DEGs, whose functions were explored
through Gene Ontology enrichment analysis. A co-expression network analysis
further refined the set of genes with potential implications in disease
response. The results identify a limited set of genes that might play an
important roles in maize resistance to F. verticillioides providing new
insights into the molecular resistance mechanisms against the pathogen
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
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
Starch and thermal treatment, important factors in changing detectable fumonisins in maize post-harvest
No full textThe drying process is commonly applied to maize grain to guarantee a safe storage. Two different conditions were tested (70°C×24h and 95°C×9h) on 6 maize hybrids collected in 2010 in Italy. Maize samples were analysed for fungal incidence, kernel chemical composition (proteins, fat, starch) and free and hidden forms of fumonisins (FBs) pre- and post-drying treatments. Drying treatments reduced fungal incidence; in particular, both temperature×time combinations were able to reduce more than 85% Fusarium spp. incidence. In general, both free and total FBs increased after drying, especially at 70°C for 24h exposure. Regarding chemical composition, proteins and starch resulted unvaried, while fat content had a mean decrement of 26% and 14% after treatment at 70°C×24h and 95°C×9h, respectively. A possible retrogradation of starch, and in particular amylose, after heating has been proposed in this study; these changes seemed to be strongly related to the modifications in detectable fumonisin. This study confirms the variation in detectable FBs occurring after the drying treatment. Therefore, the quantification of fumonisin after the post-harvest treatments is strongly suggested to avoid maize contaminated above the legal limit to enter the food/feed chain
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
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
- …
