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Tracking the Possible Source of Listeria monocytogenes Contamination Using Random Amplified Polymorphic Deoxyribonucleic Acid (RAPD)
No full textGoing 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
Antibiotic resistance of Escherichia coli and Salmonella enterica isolated from cabbage and lettuce samples in Tamale metropolis of Ghana
No full textAntibiotic resistance of Escherichia coli and Salmonella enterica isolated from cabbage and lettuce samples in Tamale metropolis of Ghana
No full textAbstract Background Contamination of vegetables by multidrug resistant pathogens is of global concern. This is the first report on the antibiotic resistance of Escherichia coli and Salmonella enterica from lettuce and cabbage sources in the Tamale metropolis of Ghana. Method A total of 26 Escherichia coli and 36 Salmonella enterica isolates were screened against nine antibiotics using the disc diffusion method. Results The overall resistance (R), intermediate (I) and susceptibility (S) of Escherichia coli (n = 11) from the cabbages were 54.55%, 9.09% and 36.36%, respectively. Escherichia coli from cabbage samples were resistant to ofloxacin (100%), ampicillin (90.01%) and erythromycin (81.82%). The overall resistance, intermediate and susceptibility of Escherichia coli (n = 15) from lettuce samples were 52.59%, 10.37% and 37.04%, respectively. The isolates were also highly resistant to ofloxacin (100%), erythromycin (93.33%) and ampicillin (86.67%). The resistant patterns AmpOfxE, CroAmpTeOfxEC and AmpTeOfxEC (exhibited by 3 isolates each) were the commonest pattern among the Escherichia coli isolates. Overall resistance, intermediate and susceptibility of Salmonella enterica (n = 18) from cabbages were 48.77%, 11.11% and 40.12%, respectively. Salmonella enterica from cabbage samples were resistant to Ofloxacin (100%) and Erythromycin (94.4%). Overall resistance, intermediate and susceptibility of Salmonella enterica (n = 18) from lettuces were 53.70%, 10.49% and 53.70%, respectively. Lettuce Salmonella enterica isolates were also highly resistant to Ofloxacin (100%) and Erythromycin (94.4%). The resistant pattern AmpOfxE was the commonest among the Salmonella enterica isolates and was exhibited by 12 isolates. Multiple antibiotic index (MAR index) ranged from 0.33 to 0.67 for the Escherichia coli isolates. MAR index for Salmonella enterica also ranged from 0.22 to 0.78. Conclusion This study revealed that cabbage and lettuce samples in the Tamale metropolis are contaminated with antibiotic resistant Escherichia coli and Salmonella enterica
Antibiotic Classes and Antibiotic Susceptibility of Bacterial Isolates from Selected Poultry; A Mini Review
No full textAntibiotic Classes and Antibiotic Susceptibility of Bacterial Isolates from Selected Poultry
No full textABSTRACT Antibiotics are drugs that kill (bactericidal) or slow (bacteriostatic) the growth of bacteria. Broad-spectrum antibiotics treat a wide range of infections, while narrow-spectrum antibiotics are effective against only a few types of bacteria. Antibiotics are very essential in the treatment of human and animal infections caused by bacteria. They are also important for the prevention of secondary infections. Despite the importance of antibiotics, their uses have received much criticism from the consumers, responsible stakeholders and policy makers. Antibiotics have evolved over the years with relatively unprecedented resistant patterns. Various classes of antibiotics such as aminoglycosides, cephalosporins, macrolides, quinolones, tetracyclines and many more have also evolved. For instance cephalosporins have evolved from first generation to the fifth generation. These antibiotic groups use different mechanisms in combating bacteria. These mechanisms include disrupting the formation of bacteria cell wall (penicillins, cephalosporins), interfering with the synthesis of bacteria DNA (fluoroquinolones), inhibiting the bacterial protein synthesis (tetracycline) and destroying protein synthesis (macrolides, aminoglycosides). Bacterial isolates from poultry exhibit different resistance patterns. At times the resistance patterns may be the same or similar among bacterial isolates. The differences in resistance patterns are widely due to factors which include differences in geographical locations, particular bacteria species involved, the animal production systems, the extent to which antibiotics are used, sampling techniques and period of sampling
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
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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