1,720,965 research outputs found
Short-term machinery impact on microbial activity and diversity in a compacted forest soil
Get PDFForest soils are complex ecosystems including a huge biodiversity including different microbial communities that are responsible for soil nutrient cycling and organic matter decomposition. One of the main threats to forest soil health is soil compaction caused by forest exploitation activities and, in particular, by wood extraction operations. These latter may change the physical, chemical and, in turn, biological properties of soil, eventually
impacting tree growth and regeneration. However, there is a significant lack of knowledge in understanding the response of soil microbial communities to soil compaction. Furthermore, most of previous studies did not properly frame the short-term response of soil microbiota to compaction, which could serve as an early indicator of soil health. This study aims to investigate and monitor the short-term response of forest soil to severe compaction stress integrating soil physico-chemical analysis with biological and biochemical analysis. To investigate the early response of soil microbial communities to compaction over time, forest soil was analyzed 8
and 12 months after the repeated passage of a tractor pulling some logs simulating skidding operations in a heavily trafficked area for wood extraction. Despite the initial strong increase in bulk density (up to 42 %), the soil almost recovered from compaction after just one year. Most of the soil chemical parameters (i.e. pH, C, and N content) were not affected by soil compaction, while the analysis of enzymatic activity showed a change of some functions upon soil compaction in the first 8 months, followed by a substantial recovery after one year. The microbial communities showed different responses to compaction, highlighting a greater bacterial community resilience in the short term compared to the fungal community, which showed persistent and significant shifts between compacted and not-compacted soil. We also identified some indicator species that may be useful for monitoring early changes in microbial communities and activities following soil compaction
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
Selection of Rhizobium strains for inoculation of Lithuanian Pisum sativum breeding lines
Get PDFPea (Pisum sativum) is one of the most popular legume crops used in agriculture. Because of the high demand and relatively reasonable price, Lithuania has increased the cultivation of this crop and invested in the research of new effective breeding lines in the last years. Rhizobial inoculants contribute to increasing yield in legumes through N2 fixation. Therefore, the objective of this work was to identify rhizobial strains able to increase the activity of two pea breeding lines (‘DS 3637–2’ and ‘DS 3795–3’) known for high productivity, resistance to biotic and abiotic stresses, and competitiveness in respect to weeds. Six rhizobial strains isolated from pea plants were identified as members of the Rhizobium leguminosarum group and phenotypically characterized in depth by Phenotype Microarray (PM). Phenotypic differences observed were linked to their phylogeny. Then, strains were tested for their ability to stimulate the growth of the breeding lines ‘DS 3637–2’ and ‘DS 3795–3’. Reference strain Rhizobium anhuiense Z1 and Rhizobium leguminosarum sv. viciae 14ZE showed the best symbiotic performances with breeding lines ‘DS 3637–2’ and ‘DS 3795–3’, respectively. Based on the obtained results, R. leguminosarum sv. viciae strain 14ZE appears to be a new effective inoculant of peas
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
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