1,721,078 research outputs found
A model to estimate the virgin and ultimate effective stiffnesses from the response of a damaged structure to a single earthquake
No full textThe paper presents a model describing the evolution of the effective stiffness of a 'mode' of a structure subjected to an earthquake engaging it in its non-linear phase of behaviour. Such models are available in the literature, however the proposed one allows the estimate of the effective stiffnesses both of the virgin state of the structure and of its ultimate state, even when the considered excitation does not act on an undamaged system nor leads it to ultimate conditions. Only the base input and the response at a significant location of the structure need to be known to apply the procedure. This is satisfactorily checked against the results of shaking table tests performed on masonry buildings
Una procedura per l'identificazione dello stato di danno di costruzioni soggette a sisma
No full textL'articolo presenta un metodo per la valutazione del danno prodotto da un terremoto su una struttura per la quale siano disponibili registrazioni accelerometriche effettuate durante l'evento. Il danneggiamento viene descritto dalle variazioni della rigidezza efficace ( keff) la cui evoluzione durante l'intera 'vita' della struttura' e' modellata mediante un sistema ad elementi distribuiti disposti in parallelo. I parametri del modello sono determinati da una procedura di identificazione intesa a minimizzare lo scarto tra i valori di keff forniti dal modello e quelli ricavati dalla elaborazione dei segnali registrati durante il singolo evento sismico. La conoscenza della funzione rappresentativa dell'evoluzione globale di keff, consente la stima del valore originario della rigidezza efficace che, confrontato con il valore relativo al termine dell'evento sismico considerato, fornisce una stima del livello di danno raggiunto dalla struttura. Il metodo e' applicato utilizzando dati sperimentali forniti da prove su tavola vibrante condotte su edifici in muratura
Juvenile idiopathic arthritis: will etanercept be an improvement over current therapies?
No full textOverexpression of cytokines in inflamed joints plays an important role in joint inflammation and in damage to articular tissue. Biological agents aimed at specifically antagonising tumour necrosis factor (TNF) are effective in the treatment of adult rheumatoid arthritis. A recent trial of etanercept, a genetically engineered fusion protein consisting of the Fc domain of human IgG1 and the TNF receptor p75, has demonstrated that this agent is also well tolerated and effective in patients with juvenile idiopathic arthritis (JIA). Etanercept offers a promising new alternative for patients with JIA who have persistently active arthritis despite treatment with methotrexate. Further studies are needed to clarify whether etanercept is equally effective in the various onset types of JIA (oligoarthritis, polyarthritis and systemic arthritis), whether it can modify disease progression and whether it can be administered safely for long periods of time to children
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
Vulnerabilità sismica degli edifici in muratura e ipotesi per la riduzione del rischio del territorio umbro
No full textIn seguito al terremoto dell'Umbria-Marche, 1997, si riprende una valutazione di vulnerabilità sismica svolta dagli autori nel decennio precedente e se ne confrontano le previsioni con l'osservazione dei danni effettivamente avvenuti
Cytokines in juvenile rheumatoid arthritis.
No full textMost data concerning the role of cytokines in chronic arthritides have been obtained in adult rheumatoid arthritis. In this paper we review the available evidence regarding the role of the inflammatory cytokines interleukin-1, interleukin-6, and tumor necrosis factor in juvenile rheumatoid arthritis, focusing in particular on the differences among the various onset types. Results from the analysis of cytokine expression may provide the basis for the use of specific anticytokine treatment. Recent clinical trials in adult rheumatoid arthritis have demonstrated the feasibility and clinical usefulness of these treatments
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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