1,721,182 research outputs found
Caractérisation des lésions néoplasiques colorectales à l’aide de clips vidéo ou de photographies haute définition : étude comparative randomisée prospective
No full textMédecine (gastro-entérologie, hépatologie)Introduction : aucune étude n'a évalué si les photos ou les vidéos étaient préférables pour la caractérisation des lésions néoplasiques colorectales (LNC). Méthodes : 20 LNC ont été montrées aux participants de l’étude, sous forme de 3-5 photos ou d'un clip vidéo. Les images étaient en lumière blanche haute définition, dont une au moins en chromoendoscopie virtuelle sans grossissement. Les participants devaient prédire la taille et le sous-type histologique des lésions à l’aide d’un formulaire et selon la classification CONECCT. L’histologique définitive et la taille étaient définies par l’anatomopathologie ou des critères combinés pour les lésions CONECCT IIC. Le critère de jugement principal était la prédiction correcte du sous-type histologique. Les critères de jugement secondaires étaient la prédiction correcte de la taille, les prédictions histologiques selon le sous-type et selon l'expérience (interne, gastro-entérologue (GE) ou expert). Résultats : les analyses ont porté sur 233 participants incluant 118 internes, 75 GE et 40 experts, répartis pour 47, 6% (111) d’entre eux dans le groupe photos et 52,4% dans le groupe vidéo (122). Les deux groupes étaient comparables. L’analyse statistique n’a pas permis de démontrer une meilleure prédiction histologique lorsque les opérateurs caractérisaient à l’aide de photos (57,3% de bonnes réponses en moyenne) ou à l’aide d’un clip vidéo (56,5%). Cependant, la taille des lésions était mieux évaluée sur photos (49.4% de bonnes réponses) que sur vidéo (45.8%, p = 0.03). La caractérisation des adénocarcinomes invasifs profonds était mieux faite par photos (47.8%) qu’en vidéo (41.1%, p = 0,02). Il n’y avait pas de différence selon l’expérience sauf chez les GE pour l’estimation de la taille (51,2% en photos, 44,3% en vidéos, p = 0,03). Conclusion : l’utilisation de la vidéo n’améliore pas la prédiction histologique en comparaison aux photographies. La taille des lésions est mieux évaluée à l’aide de photographies.Background : Accurate real-time characterization of colorectal neoplastic lesions (CNLs) during colonoscopy is important for deciding the appropriate treatment. No studies have evaluated whether still images or videoclips are better for characterization. We compared the histological predictions and size estimations of CNLs between two groups of gastroenterologists: one viewing still images and the other videoclips. Methods : Twenty CNLs were shown to the participants, in the format of either three to five still images or a videoclip. Three endoscopy experts obtained the images using high-definition white light and virtual chromoendoscopy without magnification. Stratified randomization was performed according to experience. For each lesion, participants had to assess the size and histological subtype according to the CONECCT classification (hyperplastic polyp (IH), sessile serrated lesion (IS), adenoma (IIA), high-risk adenoma or superficial adenocarcinoma (IIC), or deeply invasive adenocarcinoma (III)). The correct histological status and size were defined by the pathology reports or combined criteria between histology and expert opinion for high-risk adenoma or superficial adenocarcinoma (CONECCT IIC). Results : In total, 332 participants were randomized and 233 performed the characterization. The participants consisted of 118 residents, 75 gastroenterologists, and 40 endoscopy experts; 47.6% were shown still images and 52.4% videoclips. There was no statistically significant difference between the two groups in histological prediction, our primary endpoint. However, the lesion size was better assessed using still images than videoclips (p = 0.025). Conclusion : Videoclips do not improve the histological prediction of CNLs compared with still images. Size is better assessed using still images
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
Use of the animal models for training and research in interventional digestive endoscopy : example of endoscopic submucosal dissection
No full textLa dissection sous-muqueuse est devenue la technique de référence pour le traitement des tumeurs superficielles du tube digestif. Cependant, elle nécessité un haut niveau de technicité et un niveau de formation difficilement applicable hors Japon. Le développement et l’utilisation de modèles animaux ont permis à notre équipe de se former à la dissection sous-muqueuse, d’améliorer le matériel et les stratégies permettant une démocratisation de la technique initialement réservée à de rares centres experts. Cette stratégie est extrapolable pour de nombreuses nouvelles procédures endoscopique où la dextérité nécessaire est inversement proportionnelle au recrutement et les tutelles et les industriels vont devoir intégrer l’importance de ces structures animales de recherche et de formation dans leur accompagnement des cliniciens chercheurs en endoscopie digestive.Endoscopic submucosal dissection has become the gold-standard technique for the treatment of superficial tumors of the gastrointestinal tract. However, it requires a high level of technical skill and a level of training that is difficult to apply outside Japan. The development and use of animal models have allowed our team to train in ESD, to improve the device and strategies allowing a democratization of the technique initially limited to rare expert centers.This strategy can be extrapolated to many new endoscopic procedures where the dexterity required is inversely proportional to recruitment and the supervisors and industrialists will have to integrate the importance of these animal research and training structures in their support of academic institution in digestive endoscopy
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
Diagnostic and therapeutic management of superficial lesions of the digestive tract assisted by digital techniques
No full textLes cancers digestifs font partie des cancers les plus fréquents et leur mortalité est élevée. Ils se développent le plus souvent à partir d’une lésion bénigne qui évolue lentement et fini par devenir cancéreuse. Le dépistage organisé par endoscopie permet d’augmenter les chances de guérison grâce à une détection et à une prise en charge à un stade précoce. Depuis les progrès optiques récents en imagerie endoscopique, une grande diversité de lésions peut être visualisée au cours des examens par coloscopie. Nous avons tout d’abord démontré qu’une fois détectées, les lésions colorectales doivent être caractérisées afin de prédire l’histologie en temps réel au cours de l’endoscopie et choisir la meilleure option thérapeutique pour chaque lésion. Les biopsies (ciblées ou non) sont inutiles et peuvent rendre plus difficile une résection ultérieure. Les nombreuses classifications existantes ont cependant des limites, et nous avons donc fusionné les critères de l’ensemble des classifications usuelles dans la classification CONECCT, qui lors d’une évaluation prospective a démontré sa bonne performance diagnostique permettant un choix de traitement approprié des lésions. Nous avons ensuite cherché à développer la classification CONECCT initiale, en ajoutant d’une part les lésions présentant une zone d’invasion profonde focale, en montrant qu’une dissection sous muqueuse diagnostique est faisable pour ces lésions, et d’autre part en ajoutant les lésions sous muqueuses coliques, en montrant que la plupart n’étant pas malignes, elles ne justifient pas d’une résection endoscopique avancée mais pourraient bénéficier d’une stratégie par étape débutant par un simple échantillonnage histologique avec résection avancée pour les rares lésions malignes dans un deuxième temps. La dégénérescence des lésions n’étant pas homogène, nous avons cherché à améliorer la détection des zones d’intérêt en montrant qu’une zone colorée en vert en chromoendoscopie virtuelle ou green sign pourrait être associée à une histologie plus péjorative des lésions. Et ce d’autant plus que nous avons décrit la difficulté présentée par les systèmes IA pour détecter les lésions planes telles que les lésions festonnées et les tumeurs à extension latérale non granulaires. La caractérisation des lésions colorectales étant essentielle mais très difficile, nous avons ensuite recherché à améliorer la formation des gastroentérologues francophones à la caractérisation, par l’intermédiaire d’un groupe de travail sur un réseau social, comportant des vidéos pédagogiques dédiées à la caractérisation. Cependant, une utilisation passive du groupe avec un degré d'interaction des utilisateurs très faible n’a pas permis de montrer une progression des internes sur un an. Nous avons enfin développé une application gratuite sur ordinateur et smartphone permettant de manière efficace la caractérisation collaborative par un trio d’experts de 20 lésions colorectales publiées par 12 gastroentérologues.Digestive cancers are among the most common cancers, with a high mortality rate. They most often develop from a benign lesion that slowly evolves and eventually becomes cancerous. Organized screening by endoscopy increases the chances of cure, thanks to early detection and treatment. With recent optical advances in endoscopic imaging, a wide variety of lesions can be visualized during colonoscopic examinations. We first demonstrated that, once detected, colorectal lesions need to be characterized in order to predict histology in real time during endoscopy and choose the best therapeutic option for each lesion. Biopsies (targeted or not) are unnecessary and may make subsequent resection more difficult. The many existing classifications have their limitations, however, and we have therefore merged the criteria of all the usual classifications into the CONECCT classification, which in a prospective evaluation demonstrated its good diagnostic performance, enabling appropriate treatment choices to be made for lesions. We then sought to develop the initial CONECCT classification, by adding lesions with a focal zone of deep invasion, showing that diagnostic submucosal dissection is feasible for these lesions, and by adding colonic submucosal lesions, showing that as most are not malignant, they do not warrant advanced endoscopic resection but could benefit from a step-up strategy starting with simple histological sampling with advanced resection for the rare malignant lesions in a second stage. As lesion degeneration is not homogeneous, we sought to improve detection of areas of interest by showing that an area stained green in virtual chromoendoscopy, or green sign, could be associated with a more pejorative lesion histology. All the more so as we have described the difficulty presented by AI systems in detecting flat lesions such as sessile serrated lesions and non-granular laterally spreading tumors. As the characterization of colorectal lesions is essential but very difficult, we then sought to improve the characterization training of French-speaking gastroenterologists, via a working group on a social network, featuring educational videos dedicated to characterization. However, passive use of the group, with a very low degree of user interaction, failed to show any progression among residents over one year. Finally, we have developed a free application on computer and smartphone, enabling collaborative characterization by a trio of experts of 20 colorectal lesions published by 12 gastroenterologists
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
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