1,720,991 research outputs found
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
Impact du microbiote intestinal sur les surinfections bactériennes post-grippales
No full textIntroduction: Influenza A virus (IAV) is responsible for epidemics and, every 10-15 years, for pandemics. Secondary bacterial infections (pneumococcus) can develop in the aftermath of influenza and strongly contribute to excessive mortality of influenza. IAV infection leads to dysfunctional pulmonary defense and to altered barrier functions, thus favoring the local bacterial outgrowth and dissemination (bacteriemia). The gut microbiota has a critical role in immune responses. For instance, the depletion of the microbiota by antibiotics or its absence (germ-free animals) leads to enhanced susceptibility to respiratory infections including Streptococcus pneumoniae. We hypothesized that IAV infection may alter the functionality of the gut microbiota to favor secondary bacterial infections. Results: Metagenomic analyses demonstrated a transient alteration of the composition of the gut microbiota during IAV infection and an alteration of its fermentative activity (short chain fatty acids, SCFAs). Fecal transfer experiments revealed that the dysbiotic microbiota (collected from IAV-infected mice) can transfer enhanced susceptibility to bacterial infections in recipient mice. Restoration of SCFAs (exogenous delivery) during IAV infection reduced the incidence of bacterial superinfection. It is mainly the acetate, the main SCFA in the intestine and the blood, which causes these beneficial effects on the control of the bacterial load during superinfection. Following treatment, alveolar macrophages have a greater killing activity that lower the bacterial load in the lung and reduce the risk of mortality during superinfection. Depletion of one of the acetate receptors, GPR43, inhibits its beneficial effect. The use of agonists more specific to GPR43 (mimicking the effect of SCFAs) during influenza infection also reduces the susceptibility to bacterial superinfections. Conclusion: Collectively, these findings provide a novel mechanistic scenario for post-influenza bacterial superinfection and might have therapeutic applications in diseases associated with dysbiosis and secondary bacterial infections.Introduction: Le virus influenza A (IAV) est responsable d’épidémies de grippes chaque année, et de pandémies tous les 10 à 15 ans. Des infections bactériennes graves (infections à pneumocoques) peuvent survenir suite à l’infection grippale et contribuent à la morbidité et à la mortalité excessive de la grippe. L'infection par IAV réduit l'immunité antibactérienne, favorisant le développement local des bactéries et leur dissémination. Il a été démontré que le microbiote intestinal a un impact sur les réponses immunitaires de l'hôte. La déplétion (traitement antibiotique) ou l'absence (souris sans germe) de microbiote augmente la susceptibilité aux infections par IAV et Streptococcus pneumoniae. Nous avons émis l’hypothèse que la perturbation de la composition et de la fonction du microbiote intestinal au cours de l’infection par IAV pourrait influencer les surinfections bactériennes pulmonaires. Résultats: Une analyse métagénomique réalisée au cours de l’infection grippale montre une altération transitoire du microbiote intestinal et une perturbation de son activité de fermentation (acides gras à chaîne courte, AGCC). Des expériences de transfert de flore fécale ont montré que les souris reconstituées avec un microbiote altéré (souris grippées) sont plus sensibles à l'infection bactérienne par rapport aux souris reconstituées avec un microbiote sain. La restauration du défaut de production des AGCC (par apport exogène) chez les souris colonisées et au cours de l'infection grippale réduit la susceptibilité aux (sur)infections bactériennes. C’est principalement l’acétate, AGCC majoritaire dans l’intestin et le sang, qui entraine ces effets bénéfiques sur le contrôle de la charge bactérienne en condition de surinfection. Suite au traitement, les macrophages alvéolaires présentent une capacité plus importante à tuer les bactéries permettant de diminuer la charge bactérienne dans le poumon et diminuer le risque de mortalité au cours de la surinfection. La déplétion d’un des récepteurs de l’acétate, le récepteur couplé à la protéine G 43 (GPR43), inhibe son effet bénéfique. L’utilisation d’agonistes du récepteur GPR43 (mimant l’effet des AGCC) au cours de l’infection grippale réduit également la susceptibilité aux surinfections bactériennes. Conclusion: Ces résultats constituent une avancée majeure dans la lutte contre les surinfections bactériennes et laissent entrevoir des applications thérapeutiques. Notamment par le biais de traitement riche en fibres (source indirect d’AGCC) ou à base de probiotiques producteurs d’AGCC
Effect of the gut microbiota in post-influenza bacterial superinfections
No full textIntroduction: Le virus influenza A (IAV) est responsable d’épidémies de grippes chaque année, et de pandémies tous les 10 à 15 ans. Des infections bactériennes graves (infections à pneumocoques) peuvent survenir suite à l’infection grippale et contribuent à la morbidité et à la mortalité excessive de la grippe. L'infection par IAV réduit l'immunité antibactérienne, favorisant le développement local des bactéries et leur dissémination. Il a été démontré que le microbiote intestinal a un impact sur les réponses immunitaires de l'hôte. La déplétion (traitement antibiotique) ou l'absence (souris sans germe) de microbiote augmente la susceptibilité aux infections par IAV et Streptococcus pneumoniae. Nous avons émis l’hypothèse que la perturbation de la composition et de la fonction du microbiote intestinal au cours de l’infection par IAV pourrait influencer les surinfections bactériennes pulmonaires. Résultats: Une analyse métagénomique réalisée au cours de l’infection grippale montre une altération transitoire du microbiote intestinal et une perturbation de son activité de fermentation (acides gras à chaîne courte, AGCC). Des expériences de transfert de flore fécale ont montré que les souris reconstituées avec un microbiote altéré (souris grippées) sont plus sensibles à l'infection bactérienne par rapport aux souris reconstituées avec un microbiote sain. La restauration du défaut de production des AGCC (par apport exogène) chez les souris colonisées et au cours de l'infection grippale réduit la susceptibilité aux (sur)infections bactériennes. C’est principalement l’acétate, AGCC majoritaire dans l’intestin et le sang, qui entraine ces effets bénéfiques sur le contrôle de la charge bactérienne en condition de surinfection. Suite au traitement, les macrophages alvéolaires présentent une capacité plus importante à tuer les bactéries permettant de diminuer la charge bactérienne dans le poumon et diminuer le risque de mortalité au cours de la surinfection. La déplétion d’un des récepteurs de l’acétate, le récepteur couplé à la protéine G 43 (GPR43), inhibe son effet bénéfique. L’utilisation d’agonistes du récepteur GPR43 (mimant l’effet des AGCC) au cours de l’infection grippale réduit également la susceptibilité aux surinfections bactériennes. Conclusion: Ces résultats constituent une avancée majeure dans la lutte contre les surinfections bactériennes et laissent entrevoir des applications thérapeutiques. Notamment par le biais de traitement riche en fibres (source indirect d’AGCC) ou à base de probiotiques producteurs d’AGCC.Introduction: Influenza A virus (IAV) is responsible for epidemics and, every 10-15 years, for pandemics. Secondary bacterial infections (pneumococcus) can develop in the aftermath of influenza and strongly contribute to excessive mortality of influenza. IAV infection leads to dysfunctional pulmonary defense and to altered barrier functions, thus favoring the local bacterial outgrowth and dissemination (bacteriemia). The gut microbiota has a critical role in immune responses. For instance, the depletion of the microbiota by antibiotics or its absence (germ-free animals) leads to enhanced susceptibility to respiratory infections including Streptococcus pneumoniae. We hypothesized that IAV infection may alter the functionality of the gut microbiota to favor secondary bacterial infections. Results: Metagenomic analyses demonstrated a transient alteration of the composition of the gut microbiota during IAV infection and an alteration of its fermentative activity (short chain fatty acids, SCFAs). Fecal transfer experiments revealed that the dysbiotic microbiota (collected from IAV-infected mice) can transfer enhanced susceptibility to bacterial infections in recipient mice. Restoration of SCFAs (exogenous delivery) during IAV infection reduced the incidence of bacterial superinfection. It is mainly the acetate, the main SCFA in the intestine and the blood, which causes these beneficial effects on the control of the bacterial load during superinfection. Following treatment, alveolar macrophages have a greater killing activity that lower the bacterial load in the lung and reduce the risk of mortality during superinfection. Depletion of one of the acetate receptors, GPR43, inhibits its beneficial effect. The use of agonists more specific to GPR43 (mimicking the effect of SCFAs) during influenza infection also reduces the susceptibility to bacterial superinfections. Conclusion: Collectively, these findings provide a novel mechanistic scenario for post-influenza bacterial superinfection and might have therapeutic applications in diseases associated with dysbiosis and secondary bacterial infections
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
- …
