1,720,956 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
An Evaluative Approach to the Physical Effects of Shear Wave Elastography for Clinical Application in Pregnancy
No full textL'Elastographie par onde de cisaillement ou ShearWave Elastography (SWE) est une technique échographique de caractérisation tissulaire permettant de mesurer in vivo les propriétés élastiques des tissus vivants. Le champ d’application de ce mode est large et a prouvé son utilité dans plusieurs domaines, mais il n’inclut pas le domaine obstétrical malgré son intérêt clinique potentiel. Ce travail de thèse s’inscrit dans l’évaluation des effets sanitaires de la SWE dans le domaine de la périnatalité. Il s’appuie sur deux articles publiés et un article soumis dans des revues à comité de lecture international. Dans un premier temps, une revue de la littérature scientifique a permis de décrire les principes physiques fondamentaux des ultrasons, les différentes variantes des méthodes élastographiques, et surtout la technique SWE développé par la société Supersonic Imagine (SSI), le CHU Estaing à Clermont Ferrand ayant acquis un échographe de cette marque (modèle AIXPLORER®). Dans une seconde partie, en s’appuyant sur la méthode d’Evaluation Quantitative de Risque Sanitaire (méthode EQRS), nous avons tenté d’identifier les effets et les risques sanitaires associés aux ultrasons, d’une manière générale, et plus spécifiquement liés à l’utilisation de techniques d’élastographie sur le foetus [Article 1]. Deux effets biologiques des ultrasons ont été identifiés : un effet mécanique et un effet thermique. La radiation énergétique de l’onde de « push » a été considéré comme le facteur de risque potentiel. Dans un troisième temps, nous avons initié l’étude ELASTORISK-I afin d’évaluer l’effet thermique de cette technique élastographique. Cette étude étant éthiquement inenvisageable chez des foetus humains, elle a été réalisée en deux parties : une étude sur un tissu biologique porcin [Article 2] puis sur un phantom physique homogène (Casper-1) représentatif des tissus foetaux [Article 3].La première partie de l’Etude ELASTORISK-I (article 2, chapitre 3) reposait sur une mesure comparative par caméra infrarouge, en conditions expérimentales identiques, de l’échauffement lié aux techniques échographiques (SWE, Doppler pulsé et B-mode) sur un tissu biologique de porcin. L’objectif était de quantifier cet échauffement et de démontrer l'intérêt et la pertinence de la thermographie infrarouge, qui est une technique non invasive de mesure de la température de surface en champ complet. Cette étude a montré que la thermographie infrarouge pourrait être une approche expérimentale complémentaire aux thermocouples qui sont actuellement la référence. Les résultats ont révèlé que l’échauffement le plus important était associé à la SWE.La deuxième partie d’ELATORISK-I (article 3, chapitre 4) a été dans la continuité de notre réflexion sur la quantification et l’évaluation, dans une approche comparative, de l’échauffement lié aux différentes modalités échographique (SWE, Doppler pulsé et mode-B) en utilisant des thermocouples placés dans un phantom imitant le tissu humain (Casper-1). Les résultats de cette étude ont confirmé les données obtenues en thermographie.Ce travail de thèse a apporté des connaissances sur l’effets biologiques de l’utilisation de SWE et a contribué à initier le débat au sein de la communauté scientifique sur le sujet des risques sanitaires potentiels de l’utilisation SWE en imagerie foetale. Il ouvre le champ à d’autres expérimentations, en particulier en phantom hétérogène intégrant des « tissus osseux » (casper-2) et incite investiguer les effets mécaniques (déplacements créés par l’onde de « push » = étude ELASTORISK-II (en cours)).Shear wave elastography (SWE) is an ultrasound technique used to measure in vivo the elastic properties of tissues. The area of application of this mode is widespread and has proved its relevance in several areas, but it does not include the obstetrical field regardless of its potential clinical interest. This thesis research is part of the evaluation of the health effects of SWE in the field of perinatal care. It is based on two published articles and one article submitted in international peer-reviewed journals. First, a review of the scientific literature described the fundamental physical principles of ultrasound, the different variants of elastographic methods, and especially, the SWE technique developed by Supersonic Imagine (SSI), the CHU Estaing in Clermont Ferrand having acquired an ultrasound scanner from this brand (AIXPLORER® model). In the second part, using the Quantitative Health Risk Assessment method (QHRA method), we reviewed the literature with a view to identifying the health effects and risks of ultrasound associates in general and more specifically those related to the use of elastography techniques on the foetus[Article 1]. Two biological effects of ultrasound were identified: a mechanical effect and a thermal effect. The energetic radiation of the push wave being identified as the potential risk factor. In a third part, we initiated the ELASTORISK-I study to evaluate the thermal effect of this elastographic technique. As this study was ethically unthinkable in human fetuses, it was carried out in two parts: a study on a porcine biological tissue [Article 2] and then on a homogeneous physical phantom (Casper-1) representative of the fetal tissues [Article 3].The first part of ELASTORISK-I (article 2, chapter 3) is a comparative measurement by infrared camera, using identical experimental conditions, of the heating related to ultrasound techniques (SWE, pulsed Doppler and B-mode) on a biological tissue of a porcine. The objective was to quantify this heating and to demonstrate the interest and relevance of infrared thermography, which is a non-invasive technique for measuring surface temperature in the full field. This study shows that infrared thermography could be an experimental approach complementary to the thermocouples that are currently the reference. The results demonstrate that the most significant warm-up is associated with SWE.The second part of ELATORISK-I (article 3, chapter 4) is in the continuation of our reflection on the quantification and evaluation, in a comparative approach, of the heating related to the different ultrasound modalities (SWE, pulsed Doppler and mode-B) by using thermocouples placed in a phantom imitating human tissue (Casper-1). These results confirm the data obtained in thermography. This study has provided us with knowledge about the biological effects of SWE use and has helped to initiate debate within the scientific community about the potential health risks of SWE use in fetal imaging. It opens the field to other experiments, in particular by heterogeneous phantom combining bone (casper-2) and encourages the investigation of mechanical effects (displacements created by the "push" wave
Approche évaluative des effets physiques de l'élastographie par ondes de cisaillement en vue de son application clinique pendant la grossesse
No full textShear wave elastography (SWE) is an ultrasound technique used to measure in vivo the elastic properties of tissues. The area of application of this mode is widespread and has proved its relevance in several areas, but it does not include the obstetrical field regardless of its potential clinical interest. This thesis research is part of the evaluation of the health effects of SWE in the field of perinatal care. It is based on two published articles and one article submitted in international peer-reviewed journals. First, a review of the scientific literature described the fundamental physical principles of ultrasound, the different variants of elastographic methods, and especially, the SWE technique developed by Supersonic Imagine (SSI), the CHU Estaing in Clermont Ferrand having acquired an ultrasound scanner from this brand (AIXPLORER® model). In the second part, using the Quantitative Health Risk Assessment method (QHRA method), we reviewed the literature with a view to identifying the health effects and risks of ultrasound associates in general and more specifically those related to the use of elastography techniques on the foetus[Article 1]. Two biological effects of ultrasound were identified: a mechanical effect and a thermal effect. The energetic radiation of the push wave being identified as the potential risk factor. In a third part, we initiated the ELASTORISK-I study to evaluate the thermal effect of this elastographic technique. As this study was ethically unthinkable in human fetuses, it was carried out in two parts: a study on a porcine biological tissue [Article 2] and then on a homogeneous physical phantom (Casper-1) representative of the fetal tissues [Article 3].The first part of ELASTORISK-I (article 2, chapter 3) is a comparative measurement by infrared camera, using identical experimental conditions, of the heating related to ultrasound techniques (SWE, pulsed Doppler and B-mode) on a biological tissue of a porcine. The objective was to quantify this heating and to demonstrate the interest and relevance of infrared thermography, which is a non-invasive technique for measuring surface temperature in the full field. This study shows that infrared thermography could be an experimental approach complementary to the thermocouples that are currently the reference. The results demonstrate that the most significant warm-up is associated with SWE.The second part of ELATORISK-I (article 3, chapter 4) is in the continuation of our reflection on the quantification and evaluation, in a comparative approach, of the heating related to the different ultrasound modalities (SWE, pulsed Doppler and mode-B) by using thermocouples placed in a phantom imitating human tissue (Casper-1). These results confirm the data obtained in thermography. This study has provided us with knowledge about the biological effects of SWE use and has helped to initiate debate within the scientific community about the potential health risks of SWE use in fetal imaging. It opens the field to other experiments, in particular by heterogeneous phantom combining bone (casper-2) and encourages the investigation of mechanical effects (displacements created by the "push" wave =L'Elastographie par onde de cisaillement ou ShearWave Elastography (SWE) est une technique échographique de caractérisation tissulaire permettant de mesurer in vivo les propriétés élastiques des tissus vivants. Le champ d’application de ce mode est large et a prouvé son utilité dans plusieurs domaines, mais il n’inclut pas le domaine obstétrical malgré son intérêt clinique potentiel. Ce travail de thèse s’inscrit dans l’évaluation des effets sanitaires de la SWE dans le domaine de la périnatalité. Il s’appuie sur deux articles publiés et un article soumis dans des revues à comité de lecture international. Dans un premier temps, une revue de la littérature scientifique a permis de décrire les principes physiques fondamentaux des ultrasons, les différentes variantes des méthodes élastographiques, et surtout la technique SWE développé par la société Supersonic Imagine (SSI), le CHU Estaing à Clermont Ferrand ayant acquis un échographe de cette marque (modèle AIXPLORER®). Dans une seconde partie, en s’appuyant sur la méthode d’Evaluation Quantitative de Risque Sanitaire (méthode EQRS), nous avons tenté d’identifier les effets et les risques sanitaires associés aux ultrasons, d’une manière générale, et plus spécifiquement liés à l’utilisation de techniques d’élastographie sur le foetus [Article 1]. Deux effets biologiques des ultrasons ont été identifiés : un effet mécanique et un effet thermique. La radiation énergétique de l’onde de « push » a été considéré comme le facteur de risque potentiel. Dans un troisième temps, nous avons initié l’étude ELASTORISK-I afin d’évaluer l’effet thermique de cette technique élastographique. Cette étude étant éthiquement inenvisageable chez des foetus humains, elle a été réalisée en deux parties : une étude sur un tissu biologique porcin [Article 2] puis sur un phantom physique homogène (Casper-1) représentatif des tissus foetaux [Article 3].La première partie de l’Etude ELASTORISK-I (article 2, chapitre 3) reposait sur une mesure comparative par caméra infrarouge, en conditions expérimentales identiques, de l’échauffement lié aux techniques échographiques (SWE, Doppler pulsé et B-mode) sur un tissu biologique de porcin. L’objectif était de quantifier cet échauffement et de démontrer l'intérêt et la pertinence de la thermographie infrarouge, qui est une technique non invasive de mesure de la température de surface en champ complet. Cette étude a montré que la thermographie infrarouge pourrait être une approche expérimentale complémentaire aux thermocouples qui sont actuellement la référence. Les résultats ont révèlé que l’échauffement le plus important était associé à la SWE.La deuxième partie d’ELATORISK-I (article 3, chapitre 4) a été dans la continuité de notre réflexion sur la quantification et l’évaluation, dans une approche comparative, de l’échauffement lié aux différentes modalités échographique (SWE, Doppler pulsé et mode-B) en utilisant des thermocouples placés dans un phantom imitant le tissu humain (Casper-1). Les résultats de cette étude ont confirmé les données obtenues en thermographie.Ce travail de thèse a apporté des connaissances sur l’effets biologiques de l’utilisation de SWE et a contribué à initier le débat au sein de la communauté scientifique sur le sujet des risques sanitaires potentiels de l’utilisation SWE en imagerie foetale. Il ouvre le champ à d’autres expérimentations, en particulier en phantom hétérogène intégrant des « tissus osseux » (casper-2) et incite investiguer les effets mécaniques (déplacements créés par l’onde de « push » = étude ELASTORISK-II (en cours))
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
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