1,720,993 research outputs found
Microstructure and phase composition of bronze Montefortino helmets discovered Mediterranean seabed to explain an unusual corrosion
Full text linkTwo Monterfortino helmets, recovered in the Mediterranean seabed, show unusual features with respect to the more common helmets of the same period and found in underwater environments. Hence, they were investigated by a multi-analytical approach, which allowed us to identify the compounds constituting the helmets and to make some considerations about their metallurgy, although all the metal was converted to degradation products. The helmets, originally made in bronze, have maintained their original shape because of copper sulphides formation. The observed differences in composition between the two helmets were attributed to the position modification, of one of them, into the seabed along centuries. For the first time, a microstructural investigation permits to reconstruct the history of the aging processes involved in the total oxidation of roman bronze helmet metal
New Insight on Archaeological Metal Finds, Nails and Lead Sheathings of the Punic Ship from Battle of the Egadi Islands
Full text linkThe wreck of the Punic ship exhibited at the Archaeological Park of Lilybaeum (Marsala, Italy) is a unique example in the world. In this paper, the investigation of some metal finds (30 nails and 3 fragments of sheathings) belonging to the wreck of the Punic ship is reported. Portable X-ray fluorescence and Raman spectroscopy allowed us to identify the elements and compounds constituting them and make some deductions about their composition. X-ray diffractometry, polarised optical microscopy and scanning electron microscopy of the collected micro-samples allowed us to explain the degradation that occurred in the underwater environment
Caratterizzazione chimico-fisica dei cinturoni della necropoli di Alfedena
No full textLa ricerca descritta in questa presentazione ha riguardato l'analisi di manufatti metallici provenienti dalla necropoli di Alfedena (AQ) dove sono state rinvenute tombe di forma rettangolare scavate nelterreno, circondate e coperte da lastre di pietra, contenenti un ricco corredo funerario costituito da vasi di terracotta, spade di ferro, decorazioni e materiali in bronzo
Synthesis of yttrium aluminum garnet nanoparticles in confined environment III: Cerium doping effect
Full text linkCerium yttrium aluminum garnet (Ce:YAG, CexY3-xAl5O12) nanoparticles doped with different cerium amount were obtained by calcining the precursors synthesized via co-precipitation in w/o microemulsion for 1 h at 900 °C. The structural and morphological properties were investigated by using X-ray Diffraction (XRD), Infrared Spectroscopy (IR) and Transmission Electron Microscopy (TEM) coupled with Energy Dispersive X-ray Spectroscopy (EDS) in order to investigate the effect of doping level on formation and microstructure of obtained nanoparticles. It was found that the composition of the final products strongly depends on the concentration of cerium. The formation of single YAG phase was observed only at 0.5% cerium. For other concentrations, a mixture of YAG and yttria phases was obtained indicating an effect of the cerium on stabilization of sesquioxide phase. Optical properties of the single phase powder were also investigated in details
iViaggio: the app for safe traveling
No full texthe number of people travelling internationally increases
year after year, mainly due to the more and
more affordable cost of travelling and to the evergreater
ease of transportation. Nowadays, any destination
can be reached within 24 hours by plane, and the
improvement of economic conditions facilitates both
business and leisure travelling, as a matter of fact, according
to data from the World Tourism Organization,
the number of international trips is expected to increase
by 3% to 4% per year.1 However, international travelling
poses various health risks depending on travelers’
health conditions and the type of trip undertaken. Indeed,
travelers may experience sudden changes in altitude,
humidity, and temperature that can cause illness.
Furthermore, serious health risks can result from poorquality
housing, poor sanitary conditions, inadequate
medical services, and the unavailability of drinking
water. Potential risks strictly depend on the destination
and the characteristics of the travel, and for this reason,
anybody planning a trip should seek advice on the potential
risks related to their destination and understand
the protective measures needed to minimize the risk of
contracting a disease. The risk of infection is linked to
the epidemiology of the single country and to the different
climatic conditions, which could expose travelers to
etiological agents and vectors which are different from
those which can be found in their countries of origin,
but also to lower sanitary levels. Although doctors and
tour operators can provide great help and good advice,
it is crucial that travelers seek further information, understand
the risks associated with travelling, and take
the necessary precautions during their journey in order
to travel safely. New technologies and application
for smartphone (also known as app) might help more
and more in promoting healthy behaviors.2 The greatest
strength of health-related apps is that information is
provided through channels already used by the citizen
and perceived as “friendly.” Moreover, apps are a great
way to communicate in “one-to-many” mode, in contrast
to the standard “one-to-one” healthcare approach;
this exponentially increases the quantity of educational
content sent. Furthermore, by using the app, users produce
new electronic data and make it available to researchers
and policy makers, thus creating a new field
of big-data-based research.3, 4 The aim of this study was
to develop an applications for smartphones (“iViaggio:
the travel app, traveling in safety”) (Figure 1), designed
to provide information about the main risks associated
with travelling, also taking into consideration the kind
of trip (health risks related to environment, accidents,
traumas, and violence, potential risks of infectious diseases)
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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