1,721,018 research outputs found
Montane Bergmischwälder der Bayerischen Kalkalpen: Reduktion der Schalenwilddichte steigert nicht nur den Verjüngungserfolg, sondern auch die Bodenfruchtbarkeit
No full textMontane Bergmischwälder der Bayerischen Kalkalpen: Reduktion der Schalenwilddichte steigert nicht nur den Verjüngungserfolg, sondern auch die Bodenfruchtbarkeit
No full textFactors influencing the distribution and abundance of earthworm communities in pure and converted Scots pine stands
No full textEarthworm populations were sampled in 19 coniferous or mixed forests in Bavaria. The stands are dominated by Scots pine (Pinus sylvestris L.), or had been pure Scots pine stands before conversion to mixed stands with the broad-leaved tree species European beech (Fagus sylvatica L.), and/or pedunculate oak (Quercus robur L.) and sessile oak (Quercus petraea (Matt.) Liebl.) was started 14–66 years ago. Based on this survey, we tested whether the introduction of beech and oak into pure pine stands resulted in an altered earthworm community. In addition, we tried to explain the high observed variance in earthworm abundance and biomass by regressing them against the factors extracted by principal component analysis (PCA). The variables included in the PCA comprised soil nutrient concentrations in the Of-layer, stand parameters, annual mean precipitation and temperature, the number of diplopods as potential competitors for food and habitat, the number of invertebrate predators, and the distance to agricultural land and roadside as potential sources of earthworm immigration, respectively. Earthworms were found in each stand; however, the variance in earthworm abundance and biomass both among and within the stands was high. At two out of seven sites where pairwise comparisons between pure and converted stands were possible, significantly higher earthworm abundance and biomass were found in the converted stands. Three additional sites showed a non-significant trend towards more numerous earthworms in stands with introduced broad-leaved tree species. Moreover, at stands with broadleaves there was a shift towards an increased earthworm species diversity. The results of the PCA and subsequent regression analyses showed that the mitigation of soil acidity is the key factor for the enhancement of the epigeic earthworm fauna in Scots pine stands. We concluded that on poor sites the introduction of broadleaves influences the earthworm community positively only if it creates improved habitat conditions by, e.g., altering soil chemical properties. This requires the presence of nutrient-rich horizons in the subsoil, and means that only deep rooting and sufficiently old broad-leaved trees which are able to reach these horizons will result in improved chemical properties of the organic layer. On soils with more favourable conditions where even Scots pine stands contain considerable earthworm densities, the introduction of broad-leaved tree species may lead to a relatively prompt increase in the earthworm community and change in its species composition
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
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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