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Contribution à l'analyse de textures de radiographies osseuses pour le diagnostic précoce de l'ostéoporose
No full textOsteoporosis is characterized by a significant loss of bone mass and alterations in the microarchitecture of bone tissue. Actually, in clinical routine the diagnosis of osteoporosis is based mainly on measurement of bone mineral density. It turned out that this is not sufficient, it must be accompanied by an analysis of the microarchitecture of the bone to increase the efficiency of diagnosis. This thesis deals with the characterization of images of bone radiographs for the early diagnosis of osteoporosis. To do this, in order to better characterize the texture of bone radiography, we have introduced a new technique for data preprocessing to reduce redundancy and decrease the effect of the noise resulted by the acquisition sensors. For characterization, we propose a new analysis method inspired from the local binary patterns (LBP). The new descriptor called 1DLBP (One Dimensional Local Binary Patterns) applies in one-dimensionally manner. To evaluate the effectiveness of our approach, we conducted two clinical studies where the new descriptor (1DLBP) is compared with the conventional method (LBP) to classify osteoporotic patients and healthy subjects. The classification scores obtained were enhanced by 72% with the conventional LBP descriptor to 91% with 1DLBP descriptor.L’ostéoporose est une maladie osseuse caractérisée par une perte importante de la masse osseuse et des altérations de la microarchitecture du tissu osseux. Aujourd’hui, en routine clinique, le diagnostic de l’ostéoporose est basé principalement sur une mesure de la densité minérale osseuse qui n’est pas suffisante, car elle doit être accompagnée par une analyse de la qualité de la microarchitecture osseuse. Les travaux présentés dans cette thèse concernent la caractérisation des images de radiographies osseuses pour le diagnostic précoce de l’ostéoporose. Pour ce faire, afin de mieux caractériser la texture osseuse sur radiographie, nous avons introduit une nouvelle technique de prétraitement des données pour réduire les redondances et éliminer le bruit issu des capteurs d’acquisition. Pour la caractérisation, nous avons proposé une nouvelle technique d’analyse inspirée des motifs binaires locaux (Local Binary Patterns, LBP). Le nouveau descripteur, appelé 1DLBP (One Dimensional Local Binary Patterns) s’applique de manière unidimensionnelle. Pour tester l’efficacité de notre approche, nous avons réalisé deux études cliniques où le nouveau descripteur LBP1D est comparé à la méthode classique, LBP afin de classifier des patients ostéoporotiques et des sujets sains. Les pourcentages de classification obtenus ont été améliorés de 72% avec la méthode classique LBP à 91% avec le nouveau descripteur 1DLBP
Contribution to texture analysis of bone radiographs for early diagnosis of osteoporosis
No full textL’ostéoporose est une maladie osseuse caractérisée par une perte importante de la masse osseuse et des altérations de la microarchitecture du tissu osseux. Aujourd’hui, en routine clinique, le diagnostic de l’ostéoporose est basé principalement sur une mesure de la densité minérale osseuse qui n’est pas suffisante, car elle doit être accompagnée par une analyse de la qualité de la microarchitecture osseuse. Les travaux présentés dans cette thèse concernent la caractérisation des images de radiographies osseuses pour le diagnostic précoce de l’ostéoporose. Pour ce faire, afin de mieux caractériser la texture osseuse sur radiographie, nous avons introduit une nouvelle technique de prétraitement des données pour réduire les redondances et éliminer le bruit issu des capteurs d’acquisition. Pour la caractérisation, nous avons proposé une nouvelle technique d’analyse inspirée des motifs binaires locaux (Local Binary Patterns, LBP). Le nouveau descripteur, appelé 1DLBP (One Dimensional Local Binary Patterns) s’applique de manière unidimensionnelle. Pour tester l’efficacité de notre approche, nous avons réalisé deux études cliniques où le nouveau descripteur LBP1D est comparé à la méthode classique, LBP afin de classifier des patients ostéoporotiques et des sujets sains. Les pourcentages de classification obtenus ont été améliorés de 72% avec la méthode classique LBP à 91% avec le nouveau descripteur 1DLBP.Osteoporosis is characterized by a significant loss of bone mass and alterations in the microarchitecture of bone tissue. Actually, in clinical routine the diagnosis of osteoporosis is based mainly on measurement of bone mineral density. It turned out that this is not sufficient, it must be accompanied by an analysis of the microarchitecture of the bone to increase the efficiency of diagnosis. This thesis deals with the characterization of images of bone radiographs for the early diagnosis of osteoporosis. To do this, in order to better characterize the texture of bone radiography, we have introduced a new technique for data preprocessing to reduce redundancy and decrease the effect of the noise resulted by the acquisition sensors. For characterization, we propose a new analysis method inspired from the local binary patterns (LBP). The new descriptor called 1DLBP (One Dimensional Local Binary Patterns) applies in one-dimensionally manner. To evaluate the effectiveness of our approach, we conducted two clinical studies where the new descriptor (1DLBP) is compared with the conventional method (LBP) to classify osteoporotic patients and healthy subjects. The classification scores obtained were enhanced by 72% with the conventional LBP descriptor to 91% with 1DLBP descriptor
Contribution à l'analyse de textures de radiographies osseuses pour le diagnostic précoce de l'ostéoporose
No full textOsteoporosis is characterized by a significant loss of bone mass and alterations in the microarchitecture of bone tissue. Actually, in clinical routine the diagnosis of osteoporosis is based mainly on measurement of bone mineral density. It turned out that this is not sufficient, it must be accompanied by an analysis of the microarchitecture of the bone to increase the efficiency of diagnosis. This thesis deals with the characterization of images of bone radiographs for the early diagnosis of osteoporosis. To do this, in order to better characterize the texture of bone radiography, we have introduced a new technique for data preprocessing to reduce redundancy and decrease the effect of the noise resulted by the acquisition sensors. For characterization, we propose a new analysis method inspired from the local binary patterns (LBP). The new descriptor called 1DLBP (One Dimensional Local Binary Patterns) applies in one-dimensionally manner. To evaluate the effectiveness of our approach, we conducted two clinical studies where the new descriptor (1DLBP) is compared with the conventional method (LBP) to classify osteoporotic patients and healthy subjects. The classification scores obtained were enhanced by 72% with the conventional LBP descriptor to 91% with 1DLBP descriptor.L’ostéoporose est une maladie osseuse caractérisée par une perte importante de la masse osseuse et des altérations de la microarchitecture du tissu osseux. Aujourd’hui, en routine clinique, le diagnostic de l’ostéoporose est basé principalement sur une mesure de la densité minérale osseuse qui n’est pas suffisante, car elle doit être accompagnée par une analyse de la qualité de la microarchitecture osseuse. Les travaux présentés dans cette thèse concernent la caractérisation des images de radiographies osseuses pour le diagnostic précoce de l’ostéoporose. Pour ce faire, afin de mieux caractériser la texture osseuse sur radiographie, nous avons introduit une nouvelle technique de prétraitement des données pour réduire les redondances et éliminer le bruit issu des capteurs d’acquisition. Pour la caractérisation, nous avons proposé une nouvelle technique d’analyse inspirée des motifs binaires locaux (Local Binary Patterns, LBP). Le nouveau descripteur, appelé 1DLBP (One Dimensional Local Binary Patterns) s’applique de manière unidimensionnelle. Pour tester l’efficacité de notre approche, nous avons réalisé deux études cliniques où le nouveau descripteur LBP1D est comparé à la méthode classique, LBP afin de classifier des patients ostéoporotiques et des sujets sains. Les pourcentages de classification obtenus ont été améliorés de 72% avec la méthode classique LBP à 91% avec le nouveau descripteur 1DLBP
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
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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