1,721,077 research outputs found
Applicazione di metodi geochimici in aree a intensa pressione antropica. Il caso di studio delle discariche RSU
No full textIn order to identify new survey methods for environmental characterization of areas affected by anthropogenic pressure, several geochemical investigations were conducted in two municipal solid waste landfills of Central Italy: Cerratina landfill and Cerreto landfill.
Cerratina landfill is located in an alluvial plain of the lower Sangro river. The area is characterized by a substrate of marine origin formed by clay and sand at the base and coarse sands upwards to sands and conglomerates at the top of the formation. In this area were conducted geochemical investigations on groundwater beneath the landfill. The results of chemical analyses indicate that the samples collected from boreholes located downgradient from the landfill are contaminated. The principal contaminants are Cl-, NH4+, Fe, As, Cr, B, Hg and Zn, which exceed the limit provided by Dlgs 152/2006 during different monitoring campaigns. The boron, tritium and strontium isotopic composition of the collected water samples was analysed to evaluate the principal water-rock interaction processes and source of contamination. The results indicate that contaminated groundwater show highest tritium data and lower δ11B and 87Sr/86Sr ratio. Boron isotopes show that there are two boron sources in the study area, which are geogenic and anthropogenic sources. Sr isotope results show that sample located upgradient from the site presents lower Sr concentration and highest Sr isotopic values, which reflects weathered bedrock, while boreholes located downgradient from the site show lowest Sr values and 87Sr/86Sr ratio, probably due to pollution by landfill leachate.
Another important result was obtained by rare earths elements analyses. A positive Gadolinium anomaly was reported for one sample of studied area which reflects the anthropogenic input of the REEs in groundwater.
Cerreto landfill is located in an alluvial plain of Lazio, central Italy. The area is characterized by a substrate of continental deposits formed by clay and sand, and alluvial deposits associated with different depositional events of the main rivers presents in the area. Were conducted geochemical investigation on groundwater and soils located in the landfill site. The results show that major and trace elements for soil are below the limit provided by Italian law. Rare earths elements pattern of soils were used to evaluate possible anomalies presence and to investigate soil parent material for identifying background values of study area. The geochemical investigations show that some elements, in topsoil, present higher concentration respect to background values. Geoaccumulation index and enrichment factor show possible contamination phenomena of Ni, Cu, Cd e Pb. The results obtained for groundwater show that Fe, Mn and As exceed the limit provided by Dlgs 152/2006, but according to results obtained for soil, these elements naturally occur in the area so their principal source is geological substrate
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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