1,720,957 research outputs found
Morphologically identified benthic stomach contents from Solenette (Buglossidium luteum) in the German Bight
No full textThis dataset contains morphological stomach content data of the demersal flatfish Buglossidium luteum (solenette) collected at multiple sampling stations in the German Bight. At each station, B. luteum individuals were sampled during daytime using an epibenthic dredge (1 m width, 1 cm mesh size) towed for 5 minutes. Immediately after capture, fish were individually sealed in storage bags and frozen at −80 °C to preserve gut contents. In the laboratory, specimens were transferred to freezers and stored at −28 °C until further processing. Selected fish were defrosted and stomachs were removed and weighed. All prey items were sorted and identified to the lowest possible taxonomic level using a stereomicroscope (Leica MZ12), based on regional identification keys, taxonomic catalogues, expert consultation, and comparisons with fresh reference material. Occasionally, digestion and mastication of individuals resulted in the loss of diagnostic features. In those cases, individuals were determined at a higher taxonomic level. All taxa were quantified in terms of abundance and biomass (wet mass; measured to 0.0001g) within the stomachs, and stored in 70% ethanol. Following analysis, prey items were preserved in 70% ethanol. The stomach content dataset was curated by excluding foraminifera, nematodes, and parasites
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
The impact of temperature and organic enrichment on the bioturbation behaviour, biogeochemical cycling, and sediment stabilization activities of key Wadden Sea benthos
No full textThe impact of anthropogenic drivers on benthic ecosystem functions in a changing North Sea
No full textMacrozoobenthos play a crucial role in soft-sediment ecosystems like the North Sea by driving processes such as bioturbation (physical mixing of sediments), bioirrigation (active flushing of water into sediments), and trophic interactions (e.g., predation). These functions are essential for nutrient cycling, primary productivity, and benthic–pelagic coupling. However, benthic communities face various anthropogenic drivers, including rising temperatures, increasing organic enrichment, and indirect impacts of commercial fishing such as mesopredator release. Given that these drivers alter benthic activity, they likely also influence the ecosystem functions that benthos facilitate. Accordingly, this thesis addresses empirical knowledge gaps by integrating experiments and surveys using benthic model organisms to elucidate mechanistic links between these drivers and ecosystem functioning. Manuscripts I and II examined how temperature affects bioturbation, bioirrigation, and related nutrient fluxes. Using luminophore and bromide tracers inside incubation cores in a mesocosm tank setup, the studies quantified sediment reworking and irrigation rates of key benthic species. Warmer temperatures increased bioturbation, boosting oxygen consumption within the sediment and nutrient effluxes (Manuscript I). The abundant lugworm Arenicola marina also shifted from dominant bioirrigation activity at 15 °C to bioturbation at 20 °C, indicating a sensitivity of ecosystem processes to warming (Manuscript II). These findings suggest that rising sea temperatures may initially enhance Wadden Sea ecosystem functioning by intensifying faunal activity and strengthening coupling between the sediment–water interface. Manuscripts III and IV explored how organic enrichment influences benthic ecosystem functions using in situ microcosm incubations and different species combinations. Algal material represented coastal enrichment, while particulate organic matter (POM) reflected offshore enrichment conditions. Elevated temperature and algal enrichment enhanced bioturbation by the intertidal amphipod Corophium volutator. However, an upper threshold was reached under 15 °C, beyond which further organic enrichment likely results in a suppression of activity (Manuscript III). In parallel, POM enrichment indirectly boosted bioturbation by Corophium multisetosum by providing the shrimp predator Crangon crangon with an alternative food source, reducing predation pressure on the amphipod (Manuscript IV). These findings underscore both direct and indirect enrichment effects on bioturbation, with potential cascading impacts on broader benthic ecosystem functioning. Finally, to assess the impact of mesopredator release on benthic communities, Manuscript V examined the diet of the flatfish Buglossidium luteum. Its population has grown due to milder winters and overfishing of predators and competitors, making it a significant mesopredator likely exerting strong pressure on the benthos. Stomach content analysis, combining DNA metabarcoding and traditional morphological methods, was paired with benthic infauna data from sampling sites. Results revealed a diverse diet of 164 taxa, mainly crustaceans and polychaetes, with clear spatial variation in prey composition. This highlights B. luteum as a highly opportunistic feeder, which likely facilitates its ongoing success. Correlations with infauna data also suggest lower mobility than previously assumed. Given continued warming and fishing pressure in the North Sea, this small flatfish is poised to maintain or increase its predation pressure, tightening trophic linkages in benthic food webs. Overall, this thesis demonstrated that anthropogenic drivers (rising temperatures, enrichment, and mesopredator release) intensify ecosystem functions by boosting bioturbation, nutrient cycling, and trophic transfer. This creates a positive feedback loop; enhanced bioturbation drives organic matter remineralization and primary productivity, which, in turn, fuels more benthic activity. Essentially, these animals sustain their own productivity by reinforcing bentho-pelagic coupling while also serving as abundant resources for higher trophic levels. While the benthic system is generally robust, signs of emerging thresholds were observed under combined drivers, with species like lugworms and corophiid amphipods showing stress at high temperatures or enrichment levels. Rather than a clear tipping point, the soft sediment environment of the North Sea demonstrates partial compensation through behavioural and functional adjustments, highlighting its nonlinear response to change. This integrated perspective calls for multi-driver experiments and continuous environmental monitoring, and provides a compelling glimpse into the future of North Sea benthic ecosystem dynamics
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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