1,720,960 research outputs found
Comparative in vitro activity of imipenem against gram-positive and gram-negative aerobic bacteria from clinical isolates
Possibilità di definizione della specie Methylophilus methylotrophus, con metodiche immunologiche.
Basis for nebulized antibiotics: Droplet characterization and in vitro antimicrobial activity versus Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa
The aims of this study were to (1) quantify the particle size characteristics of several antibiotics considered suitable for aerosol therapy after aerosolization with the PARI IS/2 nebulizer (Pari GmbH, Sarnberg, Germany) and (2) determine the degree to which in vitro antimicrobial activity of these antibiotics is maintained after nebulization. The aerosolized drugs were tobramycin sulfate, streptomycin, and imipenem, with saline solution as the control. Mean mass aerodynamic diameter of the nebulized drugs was 3.25 mu m for tobramycin, 2.26 mu m for imipenem, and 2.38 mu m for streptomycin. In vitro tests showed that tobramycin and imipenem were unaltered in their bacteriostatic activity against strains of Escherichia coli (American Type Culture Collection [ATCC] 25922) and Staphylococcus aureus (ATCC 29213) as well as against Pseudomonas aeruginosa (ATCC 27853) with minimal inhibitory concentration (MIC) values less than 0.3 mu g/mL. Nebulized streptomycin showed significantly higher MIC values against P. aeruginosa (ATCC 27853). These results suggest that tobramycin and imipenem may be prescribed as an aerosol generated by jet nebulization (PARI IS/2) to treat S. aureus, E. coli, and P. aeruginosa infections without any risk of altering the drugs(1) minimum bacteriostatic activity by the nebulization process. Aerosolization of streptomycin with this nebulizer may not be as effective against P. aeruginosa because it seems to alter the bacteriostatic activity
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
We 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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