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    Production of volatile organic compounds by Aureobasidium pullulans as a potential mechanism of action against postharvest fruit pathogens

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    Two Aureobasidium pullulans strains (L1 and L8), effective against some fruit postharvest pathogens were evaluated for VOCs production as a part of their modes of action towards five pathogens (Botrytis cinerea, Colletotrichum acutatum, Penicillium expansum, Penicillium digitatum and Penicillium italicum). The VOCs were assayed with a double petri dish assay against conidia germination of target pathogens. Results obtained showed that the VOCs generated by the antagonists inhibited significantly the conidia germination of all pathogens compared to the control. In particular, the conidia germination of all Penicillium was completely inhibited by VOCs produced by L1 and L8. In in vivo tests, apples and oranges were artificially inoculated with pathogen conidia and then biofumigated with VOCs emitted by both antagonists. The antagonistic treatment controlled significantly pathogen infection, confirming the results obtained in vitro tests. The best L1 and L8 VOCs activity was observed on apple inoculated with B. cinerea where the lesion diameter reduction observed was greater than the 88%. The compounds emitted by L1 and L8 strains were identified with the solid-phase microextraction (SPME)-gas chromatographic technique. Compounds as 2-phenyl, 1-butanol-3-methyl, 1-butanol-2-methyl and 1-propanol-2-methyl belonging to the group of alcohols were mainly produced for both strains, in the first 96h of growth. These compounds were confirmed by comparison with standards. The pure compounds of VOCs cited above were used to determine the EC50 values for conidia germination of pathogens. The 1-propanol-2-methyl was the VOC least active against all tested fungi, with the EC50 values over 0.8μlml-1, while the 2-phenethyl alcohol was the most active with EC50 values lower than 0.8μlml-1, except for the C. acutatum (1.97μlml-1). The present study demonstrated, for the first time, that the production of VOCs could play an essential role in the antagonistic activity of two A. pullulans strains against five fruit postharvest pathogens

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

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    “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

    Reduction of acrylamide formation in fried potato chips by Aureobasidum pullulans L1 strain

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    Acrylamide is a potential carcinogenic molecule formed during food heat processing at high temperature (Maillard reaction). In the present study, the ability of the yeast Aureobasidium pullulans to deplete the acrylamide precursor free asparagine in fresh potatoes was investigated. A. pullulans applied before final frying changes the free amino acid composition of potatoes, decreasing the content of free asparagine by 16% and reducing acrylamide by 83% in fried potatoes. Potato browning was also reduced by yeast treatment without negative drawbacks on chip taste. This yeast, commonly used in fruit postharvest disease control, can therefore also be applied in potato and bakery industries to reduce food acrylamide content

    Production of an enzymatic protein hydrolyzate from defatted sunflower seed meal for potential application as a plant biostimulant.

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    An extensive protein hydrolyzate was produced starting from sunflower defatted seed meal, an abundant by-product of biodiesel chain oil extraction. Two-step enzymatic hydrolysis was carried out using sequentially Alcalase-Flavourzyme enzymes and a high quality hydrolyzate was produced with an interesting composition in terms of nutrient, amino acid, and peptide content for application in conventional and organic agriculture. The biostimulant properties of the hydrolyzate were investigated by carrying out auxin and gibberellin-like activity assays in Petri dishes on garden cress (Lepidium sativum L.) and lettuce (Lactuca sativa L.) seedlings and by conducting experiments in pot on maize plants. The sunflower hydrolyzate showed auxin-like, but no gibberellin-like activity and interesting effects on plant root elongation suggesting a potential use of the product as an effective biostimulant in the agricultural field

    Appropriate Similarity Measures for Author Cocitation Analysis

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    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

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    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
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