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FIGURE 5. Leucoagaricus aurantiovergens. A in Leucoagaricus cupresseoides (Agaricaceae), a new species in sect. Piloselli and L. aurantiovergens and L. pseudopilatianus redescribed from Italy
No full textFIGURE 5. Leucoagaricus aurantiovergens. A. Basidiomes in the natural habitat coll. MVBB34; B. Basidiospores in Congo Red coll. MVBB34; C. Cheilocystidia coll. MVBB34; D. Cheilocystidia coll. PAD H0061557 (isotype L. aurantiovergens); E. Cheilocystidia coll. TR MV36/97 (holotype Leucoagaricus pseudopilatianus var. roseodiffractus); F. Pileus covering elements coll. MVBB34. Scale bars: A = 1 cm, B = 10 μm, C = 30 μm, D = 20 μm, E = 25 μm, F = 30 μm. Photos: A–C, F by Vincenzo Migliozzi; D–E by Niccolò Forin.Published as part of Forin, Niccolò, Tatti, Alessia, Vizzini, Alfredo, Coppola, Alessandra & Migliozzi, Vincenzo, 2022, Leucoagaricus cupresseoides (Agaricaceae), a new species in sect. Piloselli and L. aurantiovergens and L. pseudopilatianus redescribed from Italy, pp. 126-140 in Phytotaxa 536 (2) on page 134, DOI: 10.11646/phytotaxa.536.2.2, http://zenodo.org/record/625754
FIGURE 7. Leucoagaricus pseudopilatianus. A in Leucoagaricus cupresseoides (Agaricaceae), a new species in sect. Piloselli and L. aurantiovergens and L. pseudopilatianus redescribed from Italy
No full textFIGURE 7. Leucoagaricus pseudopilatianus. A. Basidiomes in the natural habitat coll. MV LeuPil023; B. Basidiospores in Congo Red coll. MV LeuPil023; C. Cheilocystidia coll. MV LeuPil023; D. Cheilocystidia coll. PAD H0061558 (isotype L. pseudopilatianus); E. Cheilocystidia coll. TR MV41/96 (holotype Leucoagaricus pseudopilatianus var. rugosoreticulatus); F. Pileus covering elements coll. MV LeuPil023. Scale bars: A = 1 cm, B = 10 μm, C = 30 μm, D = 25 μm, E = 20 μm, F = 30 μm. Photos: A–C, F by Vincenzo Migliozzi; D–E by Niccolò Forin.Published as part of Forin, Niccolò, Tatti, Alessia, Vizzini, Alfredo, Coppola, Alessandra & Migliozzi, Vincenzo, 2022, Leucoagaricus cupresseoides (Agaricaceae), a new species in sect. Piloselli and L. aurantiovergens and L. pseudopilatianus redescribed from Italy, pp. 126-140 in Phytotaxa 536 (2) on page 137, DOI: 10.11646/phytotaxa.536.2.2, http://zenodo.org/record/625754
FIGURE 3 in Leucoagaricus cupresseoides (Agaricaceae), a new species in sect. Piloselli and L. aurantiovergens and L. pseudopilatianus redescribed from Italy
No full textFIGURE 3. Leucoagaricus cupresseoides (TR gmb01484, holotype). A. Cheilocystidia; B. Basidiospores; C. Basidia. Scale bars: A = 30 μm, B = 10 μm, C = 20 μm. Line drawings by: Vincenzo Migliozzi.Published as part of Forin, Niccolò, Tatti, Alessia, Vizzini, Alfredo, Coppola, Alessandra & Migliozzi, Vincenzo, 2022, Leucoagaricus cupresseoides (Agaricaceae), a new species in sect. Piloselli and L. aurantiovergens and L. pseudopilatianus redescribed from Italy, pp. 126-140 in Phytotaxa 536 (2) on page 131, DOI: 10.11646/phytotaxa.536.2.2, http://zenodo.org/record/625754
A next generation sequencing approach for the study of ancient fungal specimens belonging to the Pier Andrea Saccardo collection preserved at the University of Padua
Full text linkThe mycological collections represent a huge source of molecular information that may be exploited to obtain important DNA data. Indeed, it has been demonstrated that DNA barcoding projects of fungarium material have the potential to enlarge the coverage of species-level DNA sequence information deposited in public databases. However, these collections are an underused resource for building up voucher-based reference datasets, due to the difficulty to obtain DNA sequences from herbarium material. The over one century old Saccardo mycological collection preserved in the herbarium of the Botanical Garden of Padua contains about 70,000 specimens including more than 4,000 type specimens. The types in this collection have been borrowed by mycologists from all over the world for morphological revisions and consequent taxonomic reclassifications, but they have never been involved in sequencing projects so far. Accordingly, the aim of this research was to apply a DNA barcoding approach to obtain internal transcribed spacer (ITS) sequences, the consensus barcode for fungal species identification, from specimens preserved in this collection. This DNA region has been identified as a suitable marker for molecular studies that involve ancient mycological material, because only short DNA regions can be obtained from ancient and degraded DNA. In addition, in case of initial PCR failure of the ITS region, it is possible to increase the amplification/sequencing success by analyzing separately the two non-coding regions ITS1 and ITS2 that form the entire ITS. In this thesis work, an Illumina MiSeq sequencing method was applied to recover ITS1/ITS2 sequences overcoming the problems of the high level of DNA degradation of the Saccardo fungarium samples and the presence of contaminations by exogenous fungal DNA. The method required the setup of the steps involved in the samples preparation for the sequencing and in the bioinformatic data analysis, and then its efficacy was first tested to obtain ITS2 sequences from 36 non-type Peziza specimens. Despite the presence of both external fungal contamination and cross-contamination between fungarium specimens, this high-throughput sequencing method has permitted to recover ITS2 sequences from 23 out of the 36 specimens studied and also a taxonomic re-evaluation of some samples at the species level and others at genus or higher taxonomic level. Then, this next-generation sequencing (NGS) approach was used to retrieve ITS1/ITS2 sequences from type specimens belonging to the genus Nectria and from Nectria-like types classified in the collection as members of other genera. Several of these types were morphologically revised in the past by expert mycologists and placed in synonymy with other species or reclassified as members of new genera. The ITS1/ITS2 sequences were obtained for 25 different types (30 in total considering multiple specimens) out of 76 specimens involved in the study. The combined morphological and molecular data analysis suggests that there is a need to reclassify some Nectria/Nectria-like types previously reclassified only on a morphological basis and some types never considered for taxonomic revisions. In fact, for 11 types the original species name has been confirmed, for four and five types new nomenclature combinations and synonymies have been proposed respectively, while for other five types the taxonomic assignment has been possible only at genus level. Since type specimens constitute an integral part of fungal classification and nomenclature and given the outstanding and worldwide importance of the Saccardo collection, these findings provide material for a taxonomic revision of invaluable types. Moreover, the method proposed in this research not only has provided an additional scientific value to the Saccardo collection, but it can be applied to obtain important voucher-sequences from problematic herbarium material, thus expanding the databases with well-annotated ITS barcode sequences
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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