1,720,971 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
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
Détection et caractérisation des nanoparticules de dioxyde de titane dans les aliments par AF4-ICP-MS et Sp-ICP-MS
Get PDFThe thesis focuses on the development of methods for the titanium dioxide (TiO2) nanoparticles (NPs) characterization in food products. The study was separated distinctly into two axes. The development of the AF4-ICP-MS (I) method within the CEA Nano-Safety Platform in Grenoble and the development of the Sp-ICP-MS (II) method within the Food Safety Laboratory of the Anses in Maisons-Alfort.For the first axis, the electrostatic interactions between the particles and the AF4 membrane were studied. The surface charge (zeta potential) was measured for particles and membranes depending on several solvent parameters such as pH, ionic strength and the presence of surfactants. Following the several analyzes carried out, several solvent conditions have been identified as promoting the electrostatic repulsion between the particles and the membrane, which will make it possible to reduce the losses of particles at the level of the membrane. Several conditions were therefore directly tested for NPs analysis of TiO2 in AF4-ICP-MS. It has thus been shown that the conditions favoring electrostatic repulsions make it possible to improve the efficiency of the particles at the level of the AF4 system. However, the analyzes also showed that the TiO2 NPs were not sufficiently dispersed to obtain a reliable size distribution.The second part of the thesis aimed at first optimizing the data treatment of the Sp-ICP-MS method. Several improvements have been made such as the automatic calculation of the background-particle threshold, the calculation of the transport efficiency or the addition of quality control parameters. This data treatment was then compared to a software dedicated to analyzes by Sp-ICP-MS and made it possible to highlight that the internal spreadsheet gives results with a better accuracy, while providing additional parameters.In a second time an optimization of the Sp-ICP-MS method was carried out. Several parameters were therefore evaluated such as the choice of the titanium isotope, the acquisition time, the type of solvent to disperse the particles, as well as the sample collection mode and its flow rate.Finally, several foods were analyzed after setting up an extraction protocol for NPs. The results obtained made it possible to determine a size distribution of the NPs of TiO2 present in the samples.Les travaux de thèse portent sur le développement de méthodes pour la caractérisation des nanoparticules (NPs) de dioxyde de titane (TiO2) dans les aliments. L’étude a été séparée distinctement en deux axes. Le développement de la méthode AF4-ICP-MS (I) au sein de la Plateforme Nano-Sécurité du CEA de Grenoble et le développement de la méthode Sp-ICP-MS (II) au sein du Laboratoire de la Sécurité Aliments de l’Anses à Maisons-Alfort.Pour le premier axe, les interactions électrostatiques entre les particules et la membrane de l’AF4 ont été étudiées. La charge de surface (potentiel zêta) a été mesuré pour différentes type de particule et membrane en fonction de plusieurs paramètres du solvant tel que le pH, la force ionique ainsi que la présence de tensio-actifs. Suite aux nombreuses analyses effectuées plusieurs conditions de solvant ont été identifiées comme favorable à la répulsion électrostatique entre les particules et la membrane ce qui permettrai de diminuer les pertes de particules au niveau de la membrane. Plusieurs conditions ont donc été testées directement pour l’analyse de NPs de TiO2 en AF4-ICP-MS. Il a ainsi été montré que les conditions favorisant les répulsions électrostatiques permettaient d’améliorer le taux dé récupération des particules au niveau du système AF4. Cependant les analyses ont aussi montré que les NPs de TiO2 n’étaient pas suffisamment dispersées pour pouvoir obtenir une distribution en taille fiable.Le second volet de la thèse, a eu pour but, dans un premier temps, d’optimiser le traitement de données de la méthode Sp-ICP-MS. Plusieurs améliorations ont été réalisées comme le calcul automatique du seuil bruit de fond-particule, le calcul de l'efficacité de transport où encore l'ajout de paramètres de contrôle qualité. Ce traitement de données a ensuite été comparée à un logiciel dédié aux analyses par Sp-ICP-MS et a permis de mettre en avant que la feuille de calcul interne donne des résultats avec une meilleure justesse, tout en fournissant des paramètres supplémentaires.Dans un second temps une optimisation de la méthode Sp-ICP-MS a été réalisée. Plusieurs paramètres ont donc été évalués comme le choix de l’isotope de titane, le temps d’acquisition, le type de solvant pour disperser les particules, ainsi que le mode de prélèvement de l’échantillon et son débit.Enfin, plusieurs aliments ont été analysés après avoir mis en place un protocole d’extraction des NPs. Les résultats obtenus ont permis de déterminer une distribution en taille des NPs de TiO2 présentes dans les échantillons
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
Detection and characterization of titanium dioxide nanoparticles by AF4-ICP-MS and Sp-ICP-MS
No full textLes travaux de thèse portent sur le développement de méthodes pour la caractérisation des nanoparticules (NPs) de dioxyde de titane (TiO2) dans les aliments. L’étude a été séparée distinctement en deux axes. Le développement de la méthode AF4-ICP-MS (I) au sein de la Plateforme Nano-Sécurité du CEA de Grenoble et le développement de la méthode Sp-ICP-MS (II) au sein du Laboratoire de la Sécurité Aliments de l’Anses à Maisons-Alfort.Pour le premier axe, les interactions électrostatiques entre les particules et la membrane de l’AF4 ont été étudiées. La charge de surface (potentiel zêta) a été mesuré pour différentes type de particule et membrane en fonction de plusieurs paramètres du solvant tel que le pH, la force ionique ainsi que la présence de tensio-actifs. Suite aux nombreuses analyses effectuées plusieurs conditions de solvant ont été identifiées comme favorable à la répulsion électrostatique entre les particules et la membrane ce qui permettrai de diminuer les pertes de particules au niveau de la membrane. Plusieurs conditions ont donc été testées directement pour l’analyse de NPs de TiO2 en AF4-ICP-MS. Il a ainsi été montré que les conditions favorisant les répulsions électrostatiques permettaient d’améliorer le taux dé récupération des particules au niveau du système AF4. Cependant les analyses ont aussi montré que les NPs de TiO2 n’étaient pas suffisamment dispersées pour pouvoir obtenir une distribution en taille fiable.Le second volet de la thèse, a eu pour but, dans un premier temps, d’optimiser le traitement de données de la méthode Sp-ICP-MS. Plusieurs améliorations ont été réalisées comme le calcul automatique du seuil bruit de fond-particule, le calcul de l'efficacité de transport où encore l'ajout de paramètres de contrôle qualité. Ce traitement de données a ensuite été comparée à un logiciel dédié aux analyses par Sp-ICP-MS et a permis de mettre en avant que la feuille de calcul interne donne des résultats avec une meilleure justesse, tout en fournissant des paramètres supplémentaires.Dans un second temps une optimisation de la méthode Sp-ICP-MS a été réalisée. Plusieurs paramètres ont donc été évalués comme le choix de l’isotope de titane, le temps d’acquisition, le type de solvant pour disperser les particules, ainsi que le mode de prélèvement de l’échantillon et son débit.Enfin, plusieurs aliments ont été analysés après avoir mis en place un protocole d’extraction des NPs. Les résultats obtenus ont permis de déterminer une distribution en taille des NPs de TiO2 présentes dans les échantillons.The thesis focuses on the development of methods for the titanium dioxide (TiO2) nanoparticles (NPs) characterization in food products. The study was separated distinctly into two axes. The development of the AF4-ICP-MS (I) method within the CEA Nano-Safety Platform in Grenoble and the development of the Sp-ICP-MS (II) method within the Food Safety Laboratory of the Anses in Maisons-Alfort.For the first axis, the electrostatic interactions between the particles and the AF4 membrane were studied. The surface charge (zeta potential) was measured for particles and membranes depending on several solvent parameters such as pH, ionic strength and the presence of surfactants. Following the several analyzes carried out, several solvent conditions have been identified as promoting the electrostatic repulsion between the particles and the membrane, which will make it possible to reduce the losses of particles at the level of the membrane. Several conditions were therefore directly tested for NPs analysis of TiO2 in AF4-ICP-MS. It has thus been shown that the conditions favoring electrostatic repulsions make it possible to improve the efficiency of the particles at the level of the AF4 system. However, the analyzes also showed that the TiO2 NPs were not sufficiently dispersed to obtain a reliable size distribution.The second part of the thesis aimed at first optimizing the data treatment of the Sp-ICP-MS method. Several improvements have been made such as the automatic calculation of the background-particle threshold, the calculation of the transport efficiency or the addition of quality control parameters. This data treatment was then compared to a software dedicated to analyzes by Sp-ICP-MS and made it possible to highlight that the internal spreadsheet gives results with a better accuracy, while providing additional parameters.In a second time an optimization of the Sp-ICP-MS method was carried out. Several parameters were therefore evaluated such as the choice of the titanium isotope, the acquisition time, the type of solvent to disperse the particles, as well as the sample collection mode and its flow rate.Finally, several foods were analyzed after setting up an extraction protocol for NPs. The results obtained made it possible to determine a size distribution of the NPs of TiO2 present in the samples
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
