1,720,958 research outputs found
Technical and agronomical aspects in cultivating aromatic herbs in the mediterranean area
No full textContribution of soil to CO2 balance in industrial oil crops
No full textAbstract
The introduction of a oilseed crop, for energy production, in crop rotations typical of Northern Italy is very helpful for mitigating greenhouse effect; CO2 balance for oilseed crops being always positive as stated by Bona et al. (1999). Very little is known on CO2 evolution from cultivated soils. This incertitude is related to the fact that for producing more energy is necessary to increase input levels (tillage, chemicals ...) which very often induce an increase in soil organic matter degradation. On the other side, an extensive management can slowdown soil organic carbon degradation but the quantity of crop residues produced in this case are lower. In this framework it is necessary to find out the most suitable level of crop management for maximizing the CO2 balance.
In the present work the results of some simulations carried out with a model of CO2 evolution from soils (DiSOS model – Bona et al., 2003) applied to sunflower and rapeseed for oil production as a function of soil tillage level are reported. The model was used to simulate the soil organic carbon evolution from 400 cultivations of rapeseed and sunflower which came from a survey made in the Veneto Region (Po valley – northern Italy).
The CO2 balance showed the relative weight of soil tillage and the amount of crop residues in determining soil carbon budget. The main factor influencing this budget was the amount of crop residues thus underlining the relevance of reaching high yields. The tillage inputs resulted less relevant in this context
Problematiche della coltivazione intensiva delle piante infusionali in ambiente mediterraneo
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
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
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