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Emitteri Auchenorrincha presenti in Ailanthus altissima infetto dal fitoplasma della Flavecenza dorata della vite
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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
Monitoraggio dei giallumi della vite e caratterizzazione dei fitoplasmi nell’ambito del progetto finalizzato “GIA.VI” nel 2004.
No full textDuring the first year of project activity several vineyards located in grape growing areas of almost all Italian regions were monitored for yellows symptoms presence. The vineyards were selected according with previous surveys performed by some of the teams participating into this project; new localities were also surveyed in order to obtain more detailed informations about distribution and aetiology of grapevine yellows (GY) in Italy. The surveys were carried out in September-October, in some cases also in June, and leaf samples were collected from symptomatic plants in order to perform phytoplasma detection and identification. About 500 samples from the regions listed in Table were tested, nucleic acid extraction was carried out by the different teams according with published protocols (Prince et al., 1993; Barba et al., 1998; Angelini et al., 2001).
Molecular analyses were carried out by PCR/RFLP and Flavescence Dorée (FD) or Bois Noir (BN) phytoplasmas were identified by direct PCR with universal primers P1/P7 followed by nested PCR with primers specific for ribosomal groups 16SrV and 16SrI/XII and RFLP analyses with BfaI and MseI respectively. Samples positive to 16SrV group phytoplasmas were then riamplified following the protocol described by Martini et al. (2002) to identify ribosomal subgroups.
The results of surveys indicate the presence of GY symptoms in almost all the vineyards inspected in several of the provinces belonging to the regions in Table. Phytoplasma molecular identification allowed to confirm that 16SrXII-A phytoplasmas, BN, are widespread in all the vineyards of Italy surveyed. Flavescence Dorée presence (subgroups 16SrV-C, FD-C and 16SrV–D, FD-D) was confirmed in northern Italy regions and was detected also in some vineyards of Central Italy. FD-D appears to be more spread than FD-C, however the latter appears to be with increasing presence since it was identified also in symptomatic samples from some provinces of Umbria and Tuscany regions. Phytoplasmas belonging to aster yellows (16SrI-B) and elm yellows (16SrV-A) groups were occasionally detected in symptomatic grapevines in Calabria and Sardina, and in Emilia-Romagna regions respectively
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
First report of “flavescence dorée” phytoplasma identification and characterization in the leafhopper species Graphocephala fennahi, Japananus hyalinus, Hishimonus hamatus
Get PDFDuring a survey conducted in Canton Ticino (Southern Switzerland) and focused on edges and woods surrounding vineyards infected with “flavescence dorée” (FD) 5,137 leafhoppers and planthoppers were captured, by means of yellow sticky traps exposed from June 22nd to October 21st, 2017. In particular, ten traps were placed in a plot in Stabio, twelve in a plot in Bedano and eight in a vineyard in Rovio and changed every week. Among the captured insects, 53 were Graphocephala fennahi, 38 Japananus hyalinus, and 17 Hishimonus hamatus. G. fennahi specimens were caught during all the vegetative season, while the captures of J. hyalinus were limited from the end of June until the end of August, and those of H. hamatus between the second week of July and late October. The specimens of the three species were detached from the traps for DNA extraction and subsequent molecular analyses for the identification of 16SrV group phytoplasmas. After a first screening conducted with a group specific real time PCR, the positive samples were amplified by nested PCR both on the ribosomal gene region and on the secY-map genetic locus. RFLP analysis was performed on the ribosomal gene amplicons, whereas double-stranded sequencing was conducted for the purified secY-map PCR products. The molecular analyses evidenced the presence of phytoplasmas in three samples: one specimen of H. hamatus out of eight analysed samples; one pooled sample of J. hyalinus, grouping five insects, out of ten; one pooled sample of G. fennahi, grouping three insects, out of 14. The RFLP analyses showed that all the phytoplasmas present in the three samples belonged to the 16SrV-C ribosomal subgroup. The secY-map sequencing revealed that H. hamatus was infected with the M12 genotype and J. hyalinus with the M50 one. On the opposite, at least two different phytoplasma genotypes were present in the positive pooled sample of G. fennahi, as various double peaks could be observed in its chromatograms. Phytoplasmas with both M12 and M50 secY-map genotypes can be transmitted by the vector of FD Scaphoideus titanus and they are probably involved in FD outbreaks in some European regions. So far M12 had been found in grapevines from North-Western Italy; M50 had been detected in grapevines and in alders among plants, and in S. titanus, Orientus ishidae and Oncopsis alni among insects, in Italy, France, Hungary and Germany. In this study, the entomofauna present on the vine canopy was not addressed, however H. hamatus was already sporadically identified in Switzerland on the vineyard floor vegetation and on the vine canopy. Moreover, specimens of all the species caught were observed on plants facing towards the vineyards. In conclusion, the finding and characterization of FD phytoplasma genotypes in the three insect species examined suggest that these leafhoppers could play a role in the epidemiological cycle of FD, if, in the future, their ability to acquire and transmit the phytoplasma to other plants and in particular to grapevine is demonstrated. The low density of captures and positivity suggests that this role could be marginal
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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