1,720,981 research outputs found
Controllo microbiologico di prodotti alimentari ed attrezzature finalizzato alla verifica di sistemi HACCP e GMP.
No full textGenotoxic activity of 4,4',5'-trimethyazopsoralen on plasmid DNA.
No full textTERATOGENESIS, CARCINOGENESIS AND MUTAGENESI
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
Sub-Mic effects of a proline-rich antibacterial peptide on clinical isolates of Acinetobacter baumannii
No full textINTRODUCTION:
Acinetobacter baumannii is one of the most important nosocomial pathogens, mainly due to its ability to accumulate antibiotic-resistances and to persist in the hospital environment - characteristics related to biofilm production. It is well-known that A. baumannii is inhibited by the proline-rich peptide Bac7(1-35), but its putative effects at sub-MICs were never considered.
AIMS:
We examined the sub-MIC effect of Bac7(1-35) on the growth rate, resistance induction and some A. baumannii features linked to virulence.
METHODOLOGY:
Growth kinetics in the presence of sub-MICs of Bac7(1-35) were evaluated spectrophotometrically. Peptide uptake was quantified by cytometric analysis. The ability of Bac7(1-35) to interfere with biofilm production was investigated by the crystal violet method and confocal microscopy. Bacterial motility was observed at the interphase between a layer of a semi-solid medium and the polystyrene bottom of a Petri dish. The induction of resistance was evaluated after serial passages with sub-MICs of the peptide.
RESULTS:
Although the MIC of Bac7(1-35) was between 2-4 μM for all tested strains, its effect on the growth rate at sub-MICs was strain-dependent and correlated with the amount of peptide internalized by each strain. Sub-MICs of Bac7(1-35) induced a strongly strain-dependent effect on biofilm formation and reduced motility in almost all strains, but interestingly the peptide did not induce resistance.
CONCLUSION:
Bac7(1-35) is internalized into A. baumannii and is able to inhibit biofilm formation and bacterial motility, without inducing resistance. This study stresses the importance of considering possible effects that antimicrobials could have at sub-MICs, mimicking a common condition during antibiotic treatment
Discovery and characterisation of novel CHHs involved in the immune response of the red swamp crayfish Procambarus clarkii
No full textCrustacean hyperglycaemic hormone (CHH) has many functions to regulate carbohydrate metabolism, ecdysis and reproduction including ion transport in crustaceans. Furthermore, rapid mobilization of neuropeptides, including CHHs, from the sinus gland in the eyestalks represent the primary response to stress.
Here we report the identification of two potential transcripts pertaining to the CHH family in Procambarus clarkii, thanks to a whole-transcriptome sequencing approach.
These two members, named CHHip (CHH Immune-related Procambarus) and CHHop (CHH homologous Procambarus) share the typical features of the CHH (the presence of a CHH-precursor-related peptides between the signal peptide and the peptide, and 6 conserved cysteines involved in the three typical disulfide bonds of the CHH-superfamily) and they have been found up-regulated following the knock-down of the main CHH isoforms through RNA interference.
To shed light on their possible role in the immune response of P. clarkii two experiments have been performed to evaluate CHHip and CHHop relative expression in the eyestalk in response to a lipopolysaccharide (LPS)- and a Staphylococcus aureus-challenges (1 μg/animal (body weight 40 g) of LPS and S. aureus 3x108 CFU/100 μl per animal, respectively).
Following the LPS injection, only CHHip increased significantly (7-fold at 2 hours post injectionhpi and 14-fold at 4 hpi, p-value ≤ 0.01). S. aureus injection triggered CHHip at 6 and 12 hpi (p-value ≤ 0.05), but not at 24 hpi. Conversely, CHHop resulted up-regulated exclusively at 24 hpi of S. aureus (p-value ≤ 0.05).
These preliminary findings suggest an early immunological response to bacterial infection driven by CHHip followed by an up-regulation of CHHop, with the nearly contemporary down-regulation of CHHip, at 24 hpi. These results seem to support the existence of a combined action of CHHip and CHHop in response to LPS and Gram - bacteria in a time-dependent manner and increase the spectrum of action of this family of hormones up to their direct involvement in the immune response
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