1,720,966 research outputs found
Finite element modelling of rocking and sliding effects in the seismic analysis of art objects
No full textA time-history finite element study of the seismic response of art objects is presented in this paper. Attention is focused on slender free-standing members, and metallic artworks including critical geometrical portions. The representative examples selected for the two classes are a marble column and an equestrian bronze statue, respectively. The rocking-sliding model implemented for the development of the analyses corresponds to the basic analytical and numerical simulation of the dynamic phenomenon. The safeguard of the artistic value of the objects is taken into account in the finite element investigation. The results show a high seismic vulnerability of both artworks, as assessed by an overturning-related near-collapse response of the column, and a plasticization-induced collapse of the statue, at the maximum considered earthquake level
Mutual seismic assessment and isolation of different art objects
No full textNew developments of a research programme dedicated to the seismic performance assessment and base isolation protection of art objects are presented in this paper. The investigation field has been extended from massive marble statues, considered at first step of this study, to slender free-standing columns, and bronze statues with highly vulnerable geometrical portions. A semicircular marble column and an equestrian bronze sculpture located in the main hall of the Restoration Laboratories of the Opificio delle Pietre Dure Institute in Florence are examined as representative case studies of the two classes, respectively. Rocking and sliding effects are simulated in the time-history assessment analyses of both artefacts, carried out by introducing all simultaneous components of seismic action as input. The results show an overturning-related near-collapse response of the column, and a plasticization-induced collapse of the statue, at the maximum considered earthquake level. In view of the different material and structural characteristics of the two artworks and several other art objects and equipments situated in the same hall, a mutual advanced seismic protection strategy is adopted, consisting in the base isolation of the floor by means of double curved surface sliders. This retrofit measure guarantees completely undamaged response conditions of the column and the statue, without requiring direct interventions on the two artworks. At the same time, the base-isolated floor constitutes a highly protective support for the hi-tech equipments housed in the Laboratories, as well as for any other artefact to be placed on it in the future
Modelling of rocking and sliding effects in the seismic analysis of a free-standing column
Get PDFA study on the seismic response of a free-standing marble column, including rocking and sliding effects, is presented in this paper. The rocking-sliding model implemented for the development of the analyses corresponds to the basic theoretical and numerical simulation of the dynamic phenomenon. The assessment procedure adopted for the application of the model to the non-linear dynamic incremental time-history investigation is checked by comparison with simplified rigid body-based analytical predictions of the rocking-onset response acceleration and the overturning critical velocity. The results show a high seismic vulnerability of the column, as identified by severe damage at the basic design earthquake level, and an overturning-related near-collapse response at the maximum considered earthquake level
Differential interferon gene expression in bronchiolitis caused by respiratory syncytial virus-A genotype ON1
No full textBronchiolitis severity is determined by a complex interaction among viral replication and antiviral immunity. The current respiratory syncytial virus (RSV)-A, genotype ON1 demonstrated a high replicative capacity but seemed to be clinically less severe than the previously circulating RSV-A, NA1. To learn insights about ON1 innate immune response, we analyzed expression levels of type I/III interferon (IFN)-related genes in the respiratory mucosa of infants with RSV bronchiolitis. We enrolled RSV-positive bronchiolitis patients over 12 epidemic seasons at a university hospital in Rome. From nasopharyngeal washings' cells (46 positive to NA1, 47 to ON1 and 28 to RSV-B, genotype BA), the mRNA copy number of the type III IFN receptor (IFNLR1 and IL10RB subunits), and of the type I/III IFN-stimulated genes, MxA and ISG56, was calculated using the threshold cycle relative quantification method with respect to an invariant gene. Expression levels of type III IFN receptor subunits genes positively correlated to each other and did not differ in infants infected with different RSV genotypes. The ISGs levels also positively correlated between them but differed among groups. MxA levels were significantly higher in NA1-infected infants than in those with ON1 and BA; ISG56 expression was slightly higher in NA1 than in the other strains. Interestingly, a moderate negative correlation existed between viral load and both ISGs values in ON1-infected infants only. The reduced ISG levels elicited during infections with ON1 (and BA) may cause a weaker control of RSV replication and/or an inadequate host immune response which may impact the risk of respiratory sequelae
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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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