1,720,967 research outputs found
Going 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
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
Development of rapid phage based detection methods for mycobacteria
No full textMAP is the causative agent of a wasting disease in ruminants and other animals called Johne’s disease. Culture of the organism can take months and in the case of some sheep strains of MAP, culture can take up to a year. It can take several years for an animal infected with MAP to show clinical symptoms of disease. During this subclinical stage of infection, MAP can be shed into the environment contaminating their surroundings and infecting other animals. As well as this Johne’s disease is particularly difficult to diagnose during the subclinical stage of infection.
Culture is very difficult and takes too long to be a viable method to diagnose Johne’s disease. Microscopic methods can be used on histological samples to detect MAP, however common acid-fast stains used are not specific for MAP and other mycobacteria and acid-fast organisms can be detected. Molecular methods, such as PCR, exist to rapidly detect the signature DNA sequences of these organisms, however they have the disadvantage of not being able to distinguish between live and dead organisms. Other immunological methods, such as ELISA tests, exist and are routinely used to diagnose Johne’s disease, however their sensitivity is very poor especially during the subclinical stage of disease.
The aim of these studies was to develop novel rapid methods of detecting MAP to act as an alternative to methods already available. Sample processing using magnetic separation was carried out to allow good capture of MAP cells and to allow efficient phage infection. Using the phage assay, a specific, sensitive phage based method was developed that could detect approximately 10 cells per ml of blood within 24 h in the laboratory with a sensitive, specific plaque-PCR.
This optimised detection method was then used to determine whether MAP cells could be detected in clinical blood samples of cattle suffering from Johne’s disease. The results suggest that animals experimentally and naturally infected with MAP harboured cells in their blood during subclinical and clinical stages of infection.
A novel high-throughput method of detecting mycobacteria was also developed. Using phage D29 as a novel mycobacterial DNA extraction tool, viable MAP cells were detected within 8 h and the format of the assay means that it can be adapted to be used in a high-throughput capacity.
Factors affecting phage infection and phage-host interactions were investigated to make sure the phage based methods of detection were as efficient as possible. It was found that periods of recovery were often necessary to not only make sure the phage were not inhibited but to also allow the host cells to be metabolically active as it was found that phage D29 can only infect mycobacteria cells that are metabolically active.
A fluorescent fusion-peptide capable of specifically labelling MAP cells was also developed to be used as an alternative to acid-fast staining. Peptides that were found to specifically bind to MAP cells were fused with green fluorescent protein and cells mounted on slides were specifically labelled with the fluorescent fusion protein. This resulted in a good alternative to the generic acid-fast staining methods.
The blood phage assay has shown that viable MAP cells can be found in the blood of animals suffering from Johne’s disease within 24 h and this can be confirmed using a MAP specific plaque-PCR protocol. A novel faster method to detect MAP was also developed, to cut down the time to detection of viable MAP cells to 8 h, which can be formatted to be used in a high-throughput capacity. The phage assay was used as a tool to determine different metabolic states of mycobacteria, and helped investigate optimal detection conditions when using the phage assay. Finally a novel fluorescent label was developed to detect MAP as an alternative to insensitive acid-fast staining. The development of these novel methods to rapidly, specifically and sensitively detect MAP will push further the understanding of Johne’s disease and help control it
Development of rapid phage based detection methods for mycobacteria
Get PDFMAP is the causative agent of a wasting disease in ruminants and other animals called Johne’s disease. Culture of the organism can take months and in the case of some sheep strains of MAP, culture can take up to a year. It can take several years for an animal infected with MAP to show clinical symptoms of disease. During this subclinical stage of infection, MAP can be shed into the environment contaminating their surroundings and infecting other animals. As well as this Johne’s disease is particularly difficult to diagnose during the subclinical stage of infection.
Culture is very difficult and takes too long to be a viable method to diagnose Johne’s disease. Microscopic methods can be used on histological samples to detect MAP, however common acid-fast stains used are not specific for MAP and other mycobacteria and acid-fast organisms can be detected. Molecular methods, such as PCR, exist to rapidly detect the signature DNA sequences of these organisms, however they have the disadvantage of not being able to distinguish between live and dead organisms. Other immunological methods, such as ELISA tests, exist and are routinely used to diagnose Johne’s disease, however their sensitivity is very poor especially during the subclinical stage of disease.
The aim of these studies was to develop novel rapid methods of detecting MAP to act as an alternative to methods already available. Sample processing using magnetic separation was carried out to allow good capture of MAP cells and to allow efficient phage infection. Using the phage assay, a specific, sensitive phage based method was developed that could detect approximately 10 cells per ml of blood within 24 h in the laboratory with a sensitive, specific plaque-PCR.
This optimised detection method was then used to determine whether MAP cells could be detected in clinical blood samples of cattle suffering from Johne’s disease. The results suggest that animals experimentally and naturally infected with MAP harboured cells in their blood during subclinical and clinical stages of infection.
A novel high-throughput method of detecting mycobacteria was also developed. Using phage D29 as a novel mycobacterial DNA extraction tool, viable MAP cells were detected within 8 h and the format of the assay means that it can be adapted to be used in a high-throughput capacity.
Factors affecting phage infection and phage-host interactions were investigated to make sure the phage based methods of detection were as efficient as possible. It was found that periods of recovery were often necessary to not only make sure the phage were not inhibited but to also allow the host cells to be metabolically active as it was found that phage D29 can only infect mycobacteria cells that are metabolically active.
A fluorescent fusion-peptide capable of specifically labelling MAP cells was also developed to be used as an alternative to acid-fast staining. Peptides that were found to specifically bind to MAP cells were fused with green fluorescent protein and cells mounted on slides were specifically labelled with the fluorescent fusion protein. This resulted in a good alternative to the generic acid-fast staining methods.
The blood phage assay has shown that viable MAP cells can be found in the blood of animals suffering from Johne’s disease within 24 h and this can be confirmed using a MAP specific plaque-PCR protocol. A novel faster method to detect MAP was also developed, to cut down the time to detection of viable MAP cells to 8 h, which can be formatted to be used in a high-throughput capacity. The phage assay was used as a tool to determine different metabolic states of mycobacteria, and helped investigate optimal detection conditions when using the phage assay. Finally a novel fluorescent label was developed to detect MAP as an alternative to insensitive acid-fast staining. The development of these novel methods to rapidly, specifically and sensitively detect MAP will push further the understanding of Johne’s disease and help control it
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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