1,720,973 research outputs found
Spectroscopy for the characterization of materials and cultural heritage
No full textThe use of radiation or of particles as probes to investigate the matter by spectroscopic techniques is one of the main ways followed by researchers to define its structure and properties. Furthermore, there are several mechanisms of interaction able to provide indirect information about composition, bonds, and interactions, which describe the state of the system under investigation by proposing a proper model. For this reason, Spectroscopy can be considered a powerful tool for the study of materials by the characterization of the features influencing the properties. In the last years, the application fields of spectroscopic techniques was extended from synthetic materials also to the study of goods of interests in the field of cultural heritage, more complex systems for variable composition, and less or absent prior knowledge, which requires non-invasively investigation as the main demand to preserve the integrity of the object. The chemical-physical analysis can reveal, for example, information about the production of the object (raw materials and technology of the manufacture), the aging (the chemical processes involved due to the interaction with the environment permanence in the time) and the conservation state (to tailor the actions in the restoration work or to preserve the object for future) [1]. There are some limits to the amount of information available from spectroscopy so it is necessary to develop approaches to standardize the setup and the methods for investigating a kind of object, extracting the highest amount of information with the lowest impact [2]. My research activity focused on that, developing new approaches devoted mainly to the study of archaeological metals and paintings. During the presentation, firstly a brief description of the research field will be provided, then some cases studios will be described in order to show the potentiality of spectroscopy applied to cultural heritage. One of the study regarding two Montefortino helmets [3] summarize how X-ray and neutron based spectroscopies permits to describe the metal of the goods from the production to the corrosion
Chromosome analysis and FISH mapping of ribosomal DNA (rDNA), telomere (TTAGGG)n and (GATA)n repeats in the leech Haemopis sanguisuga (L.) (Annelida: Hirudinea).
No full textNew insight on metal finds of the Punic Ship of Lilibeum
No full textIn this paper, the investigation of some finds (two nails, a head and a long shaft nail, and a
fragment of Lead sheathing) belonging to the wreck of the Punic ship and exhibited at
Museo Archeologico Regionale Lilibeo (Trapani, Italy), is reported. The X-ray
Fluorescence Spectroscopy (XRF) allowed us to identify the elements constituting them
making some discussion deductions about their composition and degradation occurred
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
Luminescent inks based on Eu:PO4 nanoparticles and polyvinyl alcohol for anti-counterfeiting
No full textVariations 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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