1,721,151 research outputs found
Changes in the fine root proteome of Fagus sylvatica L. trees associated with P-deficiency and amelioration of P-deficiency
No full textPhosphorus is often the least available macronutrient in soil. Lack in phosphorus has detrimental effect on growth and biomass production of European Fagus sylvatica L., a major trees species in temperate forests. In contrast to leaf tissues, few studies have examined changes in the root system and no study has ever investigated the proteomic changes affected in beech roots by a lack in available phosphate (P). Here, we studied roots of young Fagus sylvatica L. trees in their native soils from two forests sites with contrasting availability of P: one P rich and P poor soil. To understand also the response to P fertilization, the trees were fertilized with triple superphosphate and the proteome of fine roots of all conditions was compared. Gel-free mass-spectrometry-based shotgun proteomics revealed that the proteome was differentially affected by diverging P availabilities. The proteomic changes that took place as the result of P fertilization were dependent on the supply level of P before the fertilization. When P was supplied to the P-rich soil proteins related to cell biogenesis exhibited increased abundances. Addition of P to soil that was strongly limited in P resulted in increased abundance of proteins associated with amino acid metabolism and transport.sponsorship: The authors are grateful to M. Smiatacz and M. Franke-Klein for maintenance of the plants and help during the harvest, Kusay Arat for technical assistance at Sybioma. The Cooperation europeenne dans le domaine de la recherche scientifique et technique is acknowledged for granting a STSM scholarship to Dr. Christoph-Martin Geilfus (Action FA1306) and the Deutsche Forschungsgemeinschaft for the supporting this research by a grant to A. Polle (P0362/22-2) in the Program "Ecosystem nutrition" (SPP 1685). (Cooperation europeenne dans le domaine de la recherche scientifique et technique|Action FA1306, Deutsche Forschungsgemeinschaft|P0362/22-2, Deutsche Forschungsgemeinschaft|SPP 1685)status: Publishe
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
Op zoek naar osmotische stressmerkers in Musa: Integratie van genoomdata en eiwittechnologie in een niet-model gewas
No full textBananas and plantains are a major staple food and export product in more than 120 countries with a worldwide production of over 135 million tonnes per year. The Laboratory of Tropical Crop Improvement hosts the Bioversity International Musa Germplasm Transit Centre which contains the worlds largest banana collection with over 1400 accessions kept as in vitro plants.Water is one of the most limiting abiotic stress factors in banana production. We therefore designed a long term experimental set-up to screen the available Musa biodiversity for drought tolerance in which osmotic stress research is a first step. This research was executed at three levels: cell cultures, heterotrophic in vitro plants and autotrophic plants.Research on banana cell cultures identified more than fifty potential osmotic stress markers via proteomics and transcriptomics. To evaluate the suitability of these stress markers for future use in high-throughput screening of banana varieties, we assessed the four most promising via qPCR. We showed that all four candidates reacted to the stress treatment. One (phosphoglycerate kinase) was validated as an osmotic stress marker.Then our focus shifted from the model on cell cultures towards the plant level. We developed a heterotrophic in vitro growth model to screen five varieties representing different genome constitutions present in Musa. The proteome of the variety with the smallest growth reduction was analyzed by two-dimensional gel electrophoresis. We successfully identified 24 proteins as potential osmotic stress markers of which five (PR10, isoflavone reductase, glutathione-S-transferase, S-adenosyl methionine synthase and phosphoglucomutase) had already been identified in cell cultures and we showed that proteins belonging to the defense and reactive oxygen species metabolism and to the energy metabolism contributed to the new homeostasis in the stressed in vitro plants.Further proteomic research on autotrophic plants again revealed 35 potential stress markers of which six (HSP20, HSP70, glutathione-S-transferase, S-adenosyl methionine synthase, sucrose synthase and phosphoglycerate kinase) had already been identified in cell cultures and/or in vitro plants. Finally we focused our research on one interesting osmotic stress marker protein family, HSP70. It is not uncommon to identify several spots on a gel from two-dimensional gel electrophoresis with the same general identification of the gene family. Gene families in banana consist of paralogs, genes related by duplication within a genome, and allelic variants, genes at the same locus of homologous chromosomes. HSP70 was identified in a trail of six spots. With the availability of the Musa A and B genomes and the combinatorial use of gel-based and gel-free proteomics techniques, we were able to pinpoint in an ABB variety which paralogs and/or allelic variants were expressed and were present in the spots. We also identified an osmotic stress-responsive HSP70 encoded by the paralog located on chromosome 2.The nine osmotic stress markers (HSP20, HSP70, PR10, isoflavone reductase, glutathione-S-transferase, S-adenosyl methionine synthase, sucrose synthase, phosphoglucomutase and phosphoglycerate kinase) identified in this research should now be screened in several varieties and validated under real drought conditions. Combining the validated stress marker genes with phenotyping approaches will help in the future to diagnose the severity of stress and finally drought stress tolerance marker will aid us in the identification of drought tolerant varieties and facilitate banana breeding for drought tolerance.status: Publishe
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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