1,721,476 research outputs found
Ash dieback mortality and damage at the Botanic Garden Meise, Belgium, 2016
No full text<p>These data add to the data already published for previous years and are available at Groom, Quentin J. (2015). Ash dieback mortality and damage at the Botanic Garden Meise, Belgium. Zenodo. 10.5281/zenodo.17640.</p>
<p>Four 10m × 10m plots were laid out in the naturally regenerating woodland at the Botanic Garden Meise (WGS84: 50° 55ʹ 37ʺ N, 4° 19ʹ 18ʺ E; 50° 55ʹ 37ʺ N, 4° 19ʹ 17ʺ E; 50° 55' 38.6" N 4° 19ʹ 21ʺ E; 50° 55ʹ 39ʺ N, 4° 19ʹ 29ʺ E). They were selected because the areas contained a large number of ash saplings. Within these plots all ash seedlings greater than 40 cm tall were labelled with a small (2 cm × 4 cm) plastic tag attached with stretchable plant tie. Each tag was engraved with a unique number so that the tree could be identified. These plots were not intended to be replicates but just a convenient method of refinding the tagged trees. In the first year either the height or the girth of the tree was measured with a tape measure, depending upon whether the tree was small enough to measure the height. In 2013 and each subsequent year each tree was scored for the apparent damage caused by ash dieback (<em>Hymenoscyphus pseudoalbidus</em>). The same scoring scheme was used as that by Pliūra et al. (2011). This is a 5 point system where 1 is a dead tree; 5 is an undamaged tree and 2–4 are progressively less damaged trees. In 2016 the plots were scored on 4<sup>th</sup> May.</p>
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
Using legacy botanical literature as a source of phytogeographical data
No full textAim – Paper-based publications were the main repository for phytogeographical information until the end of the 20 th century. These texts are still an important reference source for phytogeography and potentially a valuable source of data for research on environmental change. The recent digitization of biodiversity publications, text-mining and mark-up protocols means that these data are now more accessible than ever before. Here I examine the value of legacy literature specifically for studies on phytogeography. Methods – Three contrasting data mobilisation projects are used as case studies for the extraction of phytogeographic data. Two were digitisations and XML mark-up of floras, the Flore d'Afrique Centrale from the 20 th century and the Flora of Northumberland and Durham from the 19 th century. A third case study used Chenopodium vulvaria L. as a test case, where I attempted to recover as much phytogeographic data as possible for one species, both from literature and from herbarium specimens. Results – A large amount of useful information was extractable from legacy literature. The main limitations are that most localities need georeferencing and that observations are only rarely associated with a precise date. In the case of C. vulvaria literature contributed about 20% of all available observations of the species. Literature becomes a progressively more important source of data the further back in time one looks. However, useful observations become much rarer earlier than about 1850. Main conclusions – Sourcing phytogeographic data from legacy literature is valuable. It contains observations and links to other data that are unavailable from any other source. Nevertheless, its extraction takes a substantial investment in time. Before commencing on such a project it is important to prioritise work and understand the limitations of such data, particularly with regard to georeferencing
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
R.C. Clarke & M.D. Merlin (2013) – Cannabis:Evolution and Ethnobotany
No full textR.C. Clarke & M.D. Merlin (2013) – Cannabis:Evolution and Ethnobotan
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
Data licences and organization type of contributors to the Global Biodiversity Information Facility as of 19 January 2016
No full text<p>Data from the Global Biodiversity Information Facility were extracted using R (version 3.2.0) on 9 July 2015 using the rgbif package (version 0.9.0) (Chamberlain, S., Ram, K., Barve, V. & Mcglinn, D. (2015) Package ‘rgbif’: Interface to the Global 'Biodiversity' Information Facility 'API' http://cran.r-project.org/web/packages/rgbif/rgbif.pdf). The ‘rights’ statements was extracted for all occurrence datasets with one or more observations. A total of 12,458 datasets were extracted, but only about 11% of the datasets have an explicit data-useage-rights statement at the dataset level. However, some datasets use the occurrence level ‘rights’ and ‘accessRights’ fields. To extract these data the rights information was obtained from the first record of each dataset where a rights statement was missing at the dataset level.</p>
<p>The datasets were categorized into 13 different types depending on the origin of the observations.</p>
<ol>
<li>Biodiversity Information Facility or data centre</li>
<li>Botanical Garden or Herbarium</li>
<li>Citizen science</li>
<li>Commercial</li>
<li>Data publisher</li>
<li>Educational</li>
<li>Government</li>
<li>Museum</li>
<li>Network</li>
<li>Parks Authority or Nature Reserve</li>
<li>Research institution</li>
<li>Society</li>
<li>Foundations</li>
</ol>
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
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