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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
Characterization of Moroccan Citrus Tristeza Virus (CTV) isolates and study of their genomic variability after aphid transmission
No full textA survey of Citrus tristeza virus (CTV) was carried out in the main Moroccan citrus growing areas (Souss, Gharb, Moulouya, Tadla, Haouz and Loukkos), analyzing by DTBIA a total of 5192 plants. About 20% of the tested trees proved to be CTV-infected in the groves, mainly in Loukkos region with a 60% infection rate. On the contrary, only three CTV infected plants were found in Souss region and one plant in Gharb region. No CTV infection was detected in the surveyed nurseries, plots of budwood sources and varietal collections.
CTV vectors were monitored in Gharb and Loukkos regions. Aphis spiraecola (56%) and A. gossypii (32%) were the most abundant aphid species, while no evidence of Toxoptera citricidus was reported.
Ten out of 12 selected CTV isolates showed, by coat protein gene sequencing, the highest nucleotide similarity with the T30 mild reference strain (Florida) and the Spanish mild isolate T385, with a sequence homology ranging from 98.6% to 99.4%. The remaining isolates from Loukkos clustered close to the Portuguese 19-21 severe reference strain and to the Puerto Rican Poncirus trifoliata resistance breaking (RB) severe isolate B301 (98.5% to 99.2% homology); these two Moroccan isolates induced mild stem pitting symptoms on Duncan grapefruit by biological indexing and reacted positively to the MCA13 monoclonal antibodies. This study confirmed high CTV genetic diversity in some Moroccan citrus groves. The finding of the CTV stem pitting represents a serious threat to the Moroccan citrus industry, mainly if T. citricidus is introduced in the country.
Meanwhile, aphid transmission experiments by A. gossypii and A. spiraecola on two local CTV isolates (mild and severe), were carried out in laboratory. The obtained results showed that A. gossypii was able to transmit efficiently the L-Clem2-Mor mild isolate (40%), while less was the transmission rate (13.33%) for the L-Clem1-Mor severe isolate whereas, the mild isolate was transmitted at a rate of 6.67% by A. spiraecola, which was not able to transmit the severe one. The transmission trials showed that the mild CTV isolate was more transmissible than the severe one; this may explain the prevalence of the mild isolate in the region of Loukkos.
The field CTV isolates were compared to their correspondent aphid derived sub-isolates using SSCP and sequencing analysis of the p18, p23 and p25 genes. SSCP analysis showed that the CTV isolates had the same migration patterns as their correspondent aphid derived sub-isolates, whereas, sequencing analysis of the p18, p23 and p25 genes revealed minor changes in the sequences obtained from aphid derived sub-isolates compared to their parental field isolates. Consequently, very limited changes where registered in the corresponding predicted amino acids sequences of the studied genes.
Finally, a Tissue Print (TP) real time RT-PCR assay for a rapid differentiation and identification of potential severe strains of CTV was developed and validated for testing a panel of 15 CTV isolates from the Mediterranean area; the obtained results confirmed their corresponding genotypes. This assay was equally used to test 12 CTV sources from Morocco; interestingly, the two severe isolates that induced previously mild stem pitting on Duncan grapefruit were assigned as a T36-like genotype through this assay
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
Fig tree viruses in Morocco
Get PDFFig (Ficus carica L.), widely grown in Morocco, is an important fruit crop for the country, both economically and socially. Fig mosaic disease is a complex with which at least eight viruses of different taxonomic position are associated. In 2014-2018, field surveys for viruses were carried out in the main fig growing areas of Morocco (Azilal, El Jadida, Moulay Driss Zarhoune and Taounate). A total of 117 samples were collected and checked by reverse transcription polymerase chain reaction (RT-PCR), using virus specific primers, for the presence of Fig mosaic virus (FMV), Fig leaf mottle-associated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV-2), Fig mild mottling-associated virus (FMMaV), Fig latent virus 1 (FLV-1), Fig fleck-associated virus (FFkaV) and Fig cryptic virus (FCrV). PCR was also carried out for the presence of Fig badnavirus 1 (FBaV-1). About 71% of the trees were infected with at least one virus, with mixed infections in ca. 50% of the samples. FMV was the prevailing virus (40.9% infection), especially in Azilal (47.4%) and on cv. Nabout (46.2%), followed by FLMaV-1 (30.7%). FMMaV-2, FMMaV, FFkaV and FBV-1 were detected in 25.2%, 25.2%, 8.7% and 5.5% of the samples, respectively. FLV-1 and FCrV were not found. This is the first report on the presence of FMV, FLMaV-1, FLMaV-2, FMMaV, FFkaV and FBV-1 in Morocco and offers a preliminary insight into the unsatisfactory health status of fig trees in the country. Considering that the production of figs in Morocco is increasing, more attention should be given to improving the phytosanitary condition of fig trees in the country.
Keywords: Ficus carica, RT-PCR, virus detection, fig mosaic, Morocc
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
Sanitary selection of four virus-tested fig (Ficus carica L.) cultivars in Morocco
Get PDFFig (Ficus carica L.), a fruit tree widely grown in Morocco, is affected to a very large extent by fig mosaic disease (FMD), a complex with which eight viruses of different taxonomic position are associated. In order to select virus-free fig cultivars in Morocco, field surveys were conducted, between 2014 and 2018, in 11 different commercial orchards located in four regions (Azilal, El Jadida, Moulay Driss Zarhoune and Taounate). A total of 44 leaf samples representing 11 fig cultivars, without FMD symptoms, were prospected and collected for laboratory analyses. Total nucleic acids were extracted from leaf veins and tested by PCR for the presence of FMV, FLMaV-1, FLMaV-2, FMMaV, FLV-1, FBV-1, FFkaV and FCrV using specific primers. Among the 11 tested cultivars, only four (Chetoui, Rhoudane, Elquoti Lebied and Embar Lekhel) were free from the tested viruses. This study allowed the identification of at least one “virus-tested” candidate clone from four different fig cultivars which can represent the potential mother plants for propagating materials in order to establish new fig nurseries and orchards.
Keywords: Fig, sanitary selection, viruses, Morocco
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
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