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COMPONENTI COGNITIVE, PRAGMATICHE E LINGUISTICHE NELLA COSTRUZIONE DELLA COMPETENZA DEFINITORIA IN BAMBINI PRESCOLARI: CONFRONTO TRA NOMI, VERBI E AGGETTIVI
No full textCharacterization of plasmid pAX22, encoding VIM-1 metallo-β-lactamase, reveals a new putative mechanism of In70 integron mobilization
No full textObjectives: VIM-type enzymes are among the most widespread acquired metallo-β-lactamases among Gramnegative pathogens. Integron In70 is a class 1 integron that has emerged as a successful genetic support for blaVIM-1 (one of themostprevalent blaVIM allelic variants) in Gram-negativenon-fermenters, andis usually chromosome borne. The objective of this study was to characterize plasmid pAX22 from Achromobacter xylosoxidans AX22, which represents the only In70-harbouring plasmid known so far, to gather insights into the mechanisms of evolution and dissemination of In70-like elements. Methods: The complete sequence of pAX22was obtained by pyrosequencing and assembled with Roche Newbler software. The draft sequence, completed using a PCR-based strategy, was annotated via the BASys tool and compared with known sequences using BLAST algorithms. Results: The backbone of pAX22 showed significant similarity with that of pNOR-2000, a blaVIM-2-harbouring plasmid from Pseudomonas aeruginosa, and with the TnCP23 transposon. The three elements differed from each other mainly by the class 1 integron cassette arrays and by some integron-associated structures. In pAX22, In70was associated with a novel putative transposon, Tn7017, composed of a defective Tn402-like transposon carrying In70 and the ISPa17 insertion sequence. Conclusion: Plasmid pAX22 belongs to a lineage of plasmids circulating among Gram-negative non-fermenters. In70 was probably acquired by pAX22 by transposition of Tn7017, revealing a novel putative mechanism of In70 mobilization. Our results highlight the potential role that ISPa17couldhave in mobilizing defective Tn402-like transposons carrying class 1 integrons. © The Author 2013. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved
Novel infectious diseases and emerging Gram-positive multi-resistant pathogens in hospital and community acquired infections
No full textReports on the emergence and prevalence of resistant bacterial infections in hospitals and communities raise concerns that we may soon no longer be able to rely on antibiotics as a way to control infectious diseases. Effective medical care would require the constant introduction of novel antibiotics to keep up in the "arms race" with resistant pathogens. This book closely examines the latest developments in the field of antibacterial research and development. It starts with an overview of the growing prevalence of resistant Gram-positive and Gram-negative pathogens, including their various resistance mechanisms, prevalence, risk factors and therapeutic options. The focus then shifts to a comprehensive description of all major chemical classes with antibacterial properties, their chemistry, mode of action, and the generation of analogs; information that provides the basis for the design of improved molecules to defeat microbial infections and combat the emerging resistances. In closing, recently developed compounds already in clinical use, those in preclinical or first clinical studies, and a number of promising targets to be exploited in the discovery stage are discussed
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
Summary of the available molecular methods for detection of SARS-CoV-2 during the ongoing pandemic
Full text linkSince early 2020, the COVID-19 pandemic has caused an excess in morbidity and mortality rates worldwide. Containment strategies rely firstly on rapid and sensitive laboratory diagnosis, with molecular detection of the viral genome in respiratory samples being the gold standard. The reliability of diagnostic protocols could be affected by SARS-CoV-2 genetic variability. In fact, mutations occurring during SARS-CoV-2 genomic evolution can involve the regions targeted by the diagnostic probes. Following a review of the literature and an in silico analysis of the most recently described virus variants (including the UK B 1.1.7 and the South Africa 501Y.V2 variants), we conclude that the described genetic variability should have minimal or no effect on the sensitivity of existing diagnostic protocols for SARS-CoV-2 genome detection. However, given the continuous emergence of new variants, the situation should be monitored in the future, and protocols including multiple targets should be preferred
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
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