1,721,007 research outputs found
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
How to efficiently survey floral resource availability and diversity for pollinating insects in semi-natural grasslands
Get PDFFloral resources are the foundation for insect pollinators, on which we in turn rely on for food and ecosystem functioning. Global and regional trends show that insect pollinators become increasingly endangered with modernization and intensification of land use, and thus the need to find ways of conserving insect pollinators and their habitats become more crucial. There has yet to be developed an agreed upon standard practice for surveying floral resources to assess habitat quality for pollinators. Here, I provide much needed information on the pros and cons of the two most common sampling approaches; transects and plots, and three observational metrics; inflorescence counts, occurrence in subplots (frequency) and percentage cover estimates. The comparisons were based on three basic diversity indices: species richness, abundance, and the Shannon-Weiner diversity index. The results mainly depended on the observation metrics, not the sampling approach. Both plot-based methods, i.e., occurrence in subplots and percentage cover estimates, were superior to transects with inflorescence counts, both in species detection and robustness to differences in vegetation and biomass. Occurrence in subplots seemed less prone to overestimation of clustered species and thus provided diversity measures that were more representative of the species composition at the different sites than the two other methods. Future surveys of floral resources in semi-natural grasslands should be based on vegetative cover, in order to increase efficiency of the surveys by reducing the need for repeated sampling throughout the flowering season. Vegetation surveys should also take into account the practical implications of surveyor ability of detecting species by adjusting sample unit size to allow the surveyor to get a good overview of the plot.M-ECO
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
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
Verdien av kraftgater for bevaring av stedegne insektpollinerte planter og villbier i boreale skoger
Get PDFWorldwide declines in wild pollinators are threatening the provision of vital pollination functions and services to both native plant communities and crops. Habitat loss due to human land use changes is identified as one of the main drivers of wild bee decline. Particularly, farmland abandonment and conversion of natural forests into even-aged managed stands have greatly reduced the availability of essential early successional habitats in the landscape. In recent decades, to mitigate the loss of native biodiversity, there has been a growing interest in the conservation management of human modified landscapes. Modified landscape features, such as power-line clearings, can provide valuable alternative habitats for early successional plant species, which in turn offer important flower resources for wild bees.
The main objectives for the four studies in this thesis were to study the conservation value of power-line clearings as habitat for insect-pollinated plant and wild bee communities in forest landscapes and to identify effects of different maintenance
learing practices.
We carried out a large-scale field experiment and an observational study in power-lines clearings. In the first three papers, we studied the experimental treatment effects on insectpollinated plant (forbs, shrubs, and dwarf shrubs) (Paper I), solitary bee (Paper II) and bumble bee (Paper III) communities in response to different vegetation clearing practices (treatments), where woody vegetation was: (i) cut, with woody debris left to decay; (ii) cutremove, with woody debris removed; and (iii) uncut. To study the effects of management practices we used different combinations of taxonomic and functional trait diversity indices or traits groups. We assessed the modifying influence of environmental conditions, and whether the treatment effects were maintained three years post-treatment (Paper I, II, III). In Paper II and III, we used the floral resources from Paper I as important explanatory factors for the wild bee communities. To identify the value of power-line clearings as a pollinator habitat in boreal production forests, we carried out an observational study on bumble bees (Paper IV). We studied the spatiotemporal variation in bumble bee richness and abundance between open habitats in power-line clearings and adjacent forest habitats throughout one foraging season, related to environmental conditions.
Overall, the studies presented in this thesis show that power-line clearings can be important habitats for communities of both insect-pollinated plants and wild bees, and that habitat quality can be enhanced with proper management. We found that cutting the vegetation had a positive effect on plants and wild bees compared to the uncut plots, regardless of woody debris removal (Paper I, II, III). However, the effect of management practices was context dependent. Under certain environmental conditions the removal of woody debris led to a higher richness and functional diversity of plants (Paper I) which promoted a higher functional diversity of wild bees (Paper II, III). For solitary bees, woody debris removal promoted a strong positive effect which was sustained three years after cutting. Bumble bees seemed to thrive in both cut treatments. We found that the powerline clearings are valuable open canopy habitats for bumble bees in managed forests and that the power-line clearings provide essential late-season foraging resources, particularly heather (Calluna vulgaris) (Paper IV).
In forest landscapes, power-line clearings can function as alternative habitats for wild bees in boreal forests and species associated with semi-natural habitats, providing potential nesting substrates and enhanced native flower resources. To improve habitat conditions for the solitary bees, removing the woody debris is highly recommended, whereas to improve habitat conditions for bumble bees, woody debris removal is beneficial, but not as important. Implementation of management efforts should be carefully located to areas of certain environmental conditions to achieve the best possible effect. Additionally, targeted enhancement of flower species with high nectar content or flowers with late phenology (i.e. heather), would further enhance the conservation value. Our results also highlight the importance of open habitats in managed forests and that less dense forest stands are important for wild bee conservation. To conserve native plants and wild bees species, the populations need to be maintained at a landscape level. Hence, management practices should be implemented in areas enabling connectivity between open semi-natural habitats in the landscape.
Recommendations for overall wild bee conservation would thus be to implement a mosaic of woody debris retention and removal in power-line clearings, to support diverse wild bee communities. Together, the findings of this thesis represent a foundation for developing pollinator-friendly management strategies in power-line clearings in forest landscapes and suggest how power-line clearings should be included in integrated conservation plans
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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