1,720,958 research outputs found
Environmental and energetic assessment of the use of Italian maize cultivations for bioethanol production: an LCA case study
No full textThis work presents a case study of Life Cycle Assessment (LCA) regarding the production of bioethanol from maize cultivations in Italy. The aim is to evaluate the convenience of using this biomass through the assessment of the environmental and energetic impacts of the entire process: from maize cultivation to production, distribution and final use of the biofuel. The analysis was implemented by resorting to two different approaches: the so-called “Cradle-to-grave” approach, which includes all the production steps, from raw material procurement to the final use and disposal of the product, and the so-called “Cradle-to-gate” approach, which studies, in this case, the supply chain up to the production of the biofuel, without considering its final use. The joint analyses of the individual processes in a production system make it possible to identify its impacts and critical steps, allowing assessments and comparisons with alternative productions systems to be made; in this way, it is possible to choose the more sustainable system from an environmental and energetic point of view. The production system of a traditional fossil fuel was assumed as the reference system which all the impacts of the examined processes relate to. Maize is considered to be one of the less efficient biomasses for biofuel production in terms of energy balance; moreover, it has adverse implications from the socio-economic point of view, due to the use of a food biomass for non-food purposes, which has occasionally caused sudden increases in food commodity prices. Additionally, the development of this supply chain would not be easy due to the limited availability of agricultural soil for non-food purposes, especially in Italy, and owing to high production costs. Despite this, the positive values of the energy balance for all scenarios demonstrate the environmental sustainability of this production system. Compared with petrol, the bioethanol derived from the production cycle under consideration entails a 40% reduction in CO2 emissions; in case bioethanol were to be produced from naturally dried maize, this percentage would rise to 47%; the savings obtained are essentially linked to the decrease in CO2 emissions associated with the petrol combustion process: indeed, in the production, distribution and use of petrol, the largest emissions of greenhouse gases occur during the combustion phase, followed by the production stage and last by the transportation of fuel to petrol stations. In the case of bioethanol, on the contrary, it is the production phase (farming and processing) that causes the largest amount of emissions, followed by the other phases. With reference to energy consumption, a similar trend has been observed, i.e. a 50% and a 66% saving if maize is dried naturally. To this impact category only production, and, to a lesser extent, transportation contribute. In the “Cradle-to-gate” analysis, we limited ourselves to making an energy assessment, only analysing the “Consumption of energy sources” impact category. The results of this analysis show that at equal amounts of energy contained, compared with petrol the production of biofuel requires less energy regardless of the bioethanol scenario analysed
Tuscany beans landraces, on-line identification from seeds inspection by image analysis and linear discriminant analysis
No full text
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
Nuclear DNA contents, rDNAs and Karyotype evolution in subgenus Vicia: III. The heterogeneous section Hypechusa
No full textNuclear DNA contents, automated karyotype analyses, and sequences of internal transcribed spacers from ribosomal genes have been determined in the species belonging to section Hypechusa of the subgenus Vicia.
Karyomorphological results and phylogenetic data generated from the comparison of rDNA (genes coding for rRNA) sequences showed that sect. Hypechusa is not monophyletic; however, some monophyletic units are apparent (one including Vicia galeata, V. hyrcanica, V. noeana, and V. tigridis, another including V. assyriaca, V. hybrida, V. melanops, V. mollis, and V. sericocarpa), which partly correspond tomorphology-based infrasectional groups.
The relationships among these species and the species in sections Faba, Narbonensis, Bithynicae, and Peregrinae have been also investigated
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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