1,720,973 research outputs found
Model Simulation of Cumulative Carbon Sequestration by Switchgrass (Panicum Virgatum L.) in the Mediterranean Area Using the DAYCENT Model
No full textLiterature lacks large-scale studies on cumulative C storage capacity of perennial grasses in Europe. At the same time, there is raising interest toward growing biomass crops in Europe, especially under marginal lands of the Mediterranean basin. In the present study, we used the DAYCENT model to estimate the potential of switchgrass (Panicum virgatum L.) as a bioethanol crop to store soil C in the Mediterranean basin. Two scenarios were simulated: (i) cultivation only on heathlands, shrublands, and pastures (1.76 Mha) and (ii) cultivation on heathlands, shrublands, and pastures, plus 5 % of arable lands currently used for cereals (2.97 Mha in total). Cumulative biomass resulted in 184 and 303 Mt over 15 years, while soil organic carbon (SOC) storage values were 6.1 and 12.4 Mt, respectively. Mean annual biomass yield ranged between 5.6 and 9.4 Mg ha−1, while annual SOC accumulation was 0.02 to 0.62 Mg ha−1. Fossil fuel displacement resulted in 54 and 89 Mt of C, i.e., 198 and 327 Mt of equivalent CO2 in the first and second scenarios, respectively. In the second scenario, switchgrass SOC storage was much more pronounced. However, a loss of 54 Mt of grain commodities was also caused by switchgrass cultivation on 5 % of arable lands with consequent indirect land use change (ILUC) effects. The latter were, however, quite low (16 %) when compared to environmental benefits as stored SOC
Celiac disease: is it really possible to overcome duodenal biopsy?
Full text linkWe report the case of a two-year-five-month-old child who underwent screening for celiac disease due to strong familiarity. During the first observation body weight and height were at 25th and 50th centile for gender and age. Physical examination did not reveal any sign of disease. Blood tests showed increased transaminases levels and antibodies research showed: tTG IgA: 100 UI/ml, tTG IgG: 36,6 UI/ml, EMA IgA: positive. HLA study revealed homozygous allelic combination DRB1*07;DQA102:01; DQB1* 02:02 with presence of a double copy of beta chain in the composition of the DQ2 heterodymer. Biopsy with histological examination did find neither mucosal alteration nor lymphocytic infiltrates (Marsh 0). During follow up with free diet the patient remained asymptomatic and all antibody titers decreased up to normalization. According to ESPGHAN guidelines the finding of hypertransaminasemia as sign of celiac hepatic inflammation, a more than 10-fold increase of tTG IgA and a high-risk HLA would permit diagnosis of celiac disease but histological examination done due to mismatch between paucity of clinical sings and a "multiple risk combination" excluded it, allowing diagnosis of potential celiac disease. We believe that this case is interesting because of its being in contrast with current literature data that suggest a linear relationship between antibodies levels and histological damage with tTG IgA at the upper reference range in case of potential celiac disease. According to guidelines we could have avoided intestinal biopsy but we would have considered as celiac a patient who is maybe just potentially affected
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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