1,720,965 research outputs found
Antiviral activity of Coumermycin: identification of resistant and sensitive retrovirus strains.
No full textThe effect of coumermycin A, activity on the infection and replication of murine type C retroviruses was studied in vitro. The infectivity of five prototype ecotropic retroviruses was reduced by 50 to 94%, with viral titres decreased up to even-fold. These values were substantiated by progeny production studies. Similar results were obtained with five strains of xenotropic retroviruses. Delayed inhibition of growth kinetics in mouse SC-1 cells was observed with 7-5 and 10mg/l of
coumermycin A This effect was markedly reduced after three cycles of freezing and thawing of the drug. Changes in the absorption spectra of coumermycin A, were observed after eight cycles of freezing and thawing
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
Architectural Building Techniques’ History
No full textLo studio delle strutture murarie dell’edilizia storica sottintende un sostanziale e significativo collegamento tra il fenomeno costruttivo e le componenti politiche, amministrative, economiche e sociali. Tali fattori sono particolarmente evidenti ed hanno inciso, in ogni tempo, in maniera consistente sulle caratteristiche delle tecniche costruttive e sui meccanismi di diffusione nonché sulle caratteristiche formali. L’indagine delle strutture murarie deve essere svolta con metodo e deve essere articolata in una schedatura e in una classificazione dei singoli casi individuando i ‘caratteri distintivi’ generali della tecnica muraria e le loro varianti. La schedatura fornisce sia una base dove registrare le informazioni e i dati caratterizzanti per una datazione della tipologia muraria sia uno strumento di trasmissione delle stesse notizie per ulteriori future utilizzazioni ed interpretazioni. Essa fornisce, altresì, la base analitico-descrittiva, indispensabile per ogni successivo momento interpretativo e valutativo, volto ad elaborare risposte di tipo architettonico di natura tecnica, storica ed estetica sulle tecniche murarie. Nell’articolo in oggetto si propone un’esemplificazione del metodo d’analisi e schedatura per il rilievo delle strutture murarie.The current landscape of the debate on the analytical study of building techniques, seen as an integral part of the historical-critical study of the historical, finds its roots in the investigations and contributions of historians, of treatises and technical, developed during the nineteenth century, with occasional advances in the sixteenth-XVIII.Lo study of the walls of the building tradition preindustrial implies a substantial and significant connection between the phenomenon and constructive aspects of seemingly unrelated to the nature of this, as the political, administrative, economic and social . These factors are particularly evident and have Incidentally, in a consistent manner on the peculiar characteristics of the construction technique and especially on the mechanisms of diffusion and on the characteristics formali.Il given wall can then be considered as a full document, testimony of a series of phenomena produced by a particular human society in a well-defined period of time: it is therefore to be included as part of the documents relating to a concept of history is understood in a global sense rather than sectoral, able to understand and penetrate the phenomenon of technical and economic reasons, the taste, the culture, the mentality of the different historical periods in a global view of the sequence of events in tempo.Lo study of masonry technique should therefore be approached from multiple points of view in order to reconstruct the complex and varied schedule determined by the customs local reasons for the persistence of social, political, administrative and geographical, from the geological composition of the site, the ease of obtaining the raw materials necessary for the construction and the 'culture' of skilled workers, local or no.Chiariti the assumptions and the general approach of direct research in the area, you must start with a basic analytical and descriptive, which is essential for every subsequent moment of interpretation and evaluation, designed to develop type responses architectural technical, historical and aesthetic techniques murarie.L 'investigation and the filing of the walls should be done by making a thorough classification of individual cases, thus identifying the' distinctive characteristics' general masonry technique (the presence of horizontal courses, rows of constant height, joints staggered, and the conformation and the size of the stone elements assembled on site) and their varianti.Nel classify masonry structures is therefore necessary to identify the key factors in the phenomenon: to evaluate the variables that characterize the single wall structure, so as to uniquely qualify it by certain parameters. On the basis of these will be drawn up a card for the relief of murature.Per analytical cataloging and classification of the walls must therefore operate a summary of the data taken from direct observation of the structure, trying to collect under a number of essential items and brief descriptions, the highest possible number of information. The catalog provides a basis in fact is a place to record information and data for characterizing a dating type of wall is an instrument of transfer of that information for further study interpretazioni.Lo and future uses of the building technique is so open to interpretation and a 'broad and articulated interpretation of concrete data, represented by the same walls, providing important insights to economic considerations and political-administrative, such as issues relating to the organization of the low-medieval shipyard, the influence of the corporate system and its presence in the city and in fact that papale.Per what concerns the possibility of classification and dating of the type of walls 'in tuff', the inductive analysis allowed to identify some general rules of development of the technique, which propagates in the territory Lazio characters of uniqueness and uniqueness
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
Skin papillomas and other neoplasms induced by murine sarcoma viruses in mid-gestation-infected mice.
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