1,721,026 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
Development of innovative techniques for the management of coronary heart disease in nuclear medicine
No full textLes maladies cardiovasculaires sont la première cause de mortalité dans le monde, et la maladie coronaire est responsable de la majorité de ces décès suivi par les accidents vasculaires cérébraux. La prise en charge des patients à risques cardio-vasculaire pourrait être améliorer par deux grands axes peu accessibles actuellement en pratique clinique. Le premier est constitué par l’exploration de la microcirculation coronaire, présent précocement et marqueur pronostique indépendant largement validé dans la littérature. Le deuxième axe est constitué par l’exploration de la plaque d’athérome vulnérable que ce soit au niveau coronaire ou carotidien afin de dépister les sujets à risque d’événement cardio-vasculaire et de monitorer la stratégie thérapeutique. C’est donc en réponse à ces deux axes de la prise en charge des patients que s’inscrit cette thèse avec en première partie le développement en pratique clinique de techniques ayant pour objectif d’explorer la micorcirculation coronaire (entropie perfusionnelle et quantification de la réserve perfusionnelle en scintigraphie myocardique de perfusion) et en deuxième partie de transfert clinique (Phase I) du 99mTc-cAbVCAM1-5 ciblant le VCAM-1 surexprimé dans les plaques d’athérome vulnérables. L’entropie de la perfusion est un marqueur pronostique indépendant et additif dans une population de diabétiques à haut risque cardio-vasculaire. Sa validation en population générale et son lien avec l’atteinte microcirculatoire reste à démontrer. La quantification de la réserve perfusionnelle en CZT est un paramètre fiable et permet dorénavant cette exploration en pratique clinique chez nos patients. La phase I du 99mTc-cAbVCAM1-5 est terminé chez les volontaires sains et présente une innocuité, une dosimétrie acceptable et une biodistribution nous laissant envisager une exploration des patients.Cardiovascular disease is the leading cause of death worldwide. Coronary artery disease is the first cause of these deaths followed by stroke. The management of patients at cardiovascular risk could be improved by two main axes which are not currently accessible in clinical practice. Coronary microcirculation is one of the two main axes. Present early in cardiovascular disease, its impairment is well known as an independent prognostic marker of cardiovascular function. Exploration of vulnerable plaque is the second main axe with the aim to detect patient at high risk of cardiovascular events and to monitor the therapeutic strategy. The aim of this thesis was to improve these two axes of patient care. The first part was the development of molecular imaging techniques to assess coronary microvascular dysfunction The second axis is the (perfusion entropy quantification and quantification of myocardial perfusion reserve in scintigraphy). The second part was the first-in-man injection (Phase I) of a targeting VCAM-1 radiotracer (99mTc-cAbVCAM1-5) which is overexpressed in vulnerable atheroma plaques. Perfusion entropy is an independent and additive prognostic marker in a population of diabetics at high cardiovascular risk. Its validation in the global population and its link with microcirculatory involvement remains unknown. The quantification of the perfusion reserve in CZT is a reliable parameter. Its quantification is now performed in clinical practice in our patients. Phase I of 99mTc-cAbVCAM1-5 is completed in healthy volunteers with excellent safety, acceptable dosimetry and biodistribution, allowing us to consider patient exploration....................................................................................................................................................................................
MEDECINE NUCLEAIRE ET MALADIE CORONARIENNE : EVALUATION DE TRACEURS DE LA PERFUSION MYOCARDIQUE ET DE LA PLAQUE D'ATHEROME VULNERABLE
No full textCORONARY ARTERY DISEASE IS ONE OF THE PRIMARY CAUSE OF MORTALITY WORLDWIDE. NUCLEAR MEDICINE IS THE MAJOR IMAGING TECHNIQUE FOR DIAGNOSIS AND FOLLOWING OF THIS DISEASE. PERFUSION : NOWADAYS, MAJOR RADIOACTIVE AGENTS USED IN CLINICAL PRACTICE ARE MYOCARDIAL PERFUSION TRACERS. THE REFERENCE TRACER IS THALLIUM-201. HOWEVER, 201TL PRESENTS SOME DRAWBACKS. 99MTCN-NOET HAS BEEN PROPOSED FOR ITS REPLACEMENT. THIS STUDY SHOWS THAT IN CONTRAST WITH PREVIOUS STUDIES REALIZED IN VITRO ON CARDIOMYOCYTES, VERAPAMIL, AN L-TYPE CALCIUM CHANNEL INHIBITOR, DOES NOT INHIBIT MYOCARDIAL FIXATION OF 99mTcN-NOET IN VIVO IN DOG. THIS DATA IS IN AGREEMENT WITH THE HYPOTHESIS OF A NON SPECIFIC ENDOTHELIAL FIXATION OF THIS TRACER. MOREOVER, THIS STUDY SHOWS THAT AS A PURE TRACER OF MYOCARDIAL PERFUSION, 99mTcN-NOET CAN ALSO BE USED TO ASSESS MYOCARDIAL VIABILITY ON A MODEL OF MYOCARDIAL CHRONIC INFARCTUS IN RAT. ATHEROSCLEROSIS : DISRUPTION OF VULNERABLE ATHEROSCLEROTIC PLAQUES IS THE MAIN EVENT LEADING TO CORONARY ACCIDENTS. THE SECOND PART OF THIS STUDY CONCERNS THE EVALUATION OF NEW POTENTIAL TRACERS OF THE VULNERABLE ATHEROSCLEROTIC PLAQUE IN AN EXPERIMENTAL MODEL OF RABBIT WITH AN INHERITABLE HYPERCHOLESTEROLEMIA. THE FOUR TRACERS EVALUATED (B2702(R), B2702-I, B2702-TC AND TC-RAFT-B2702) ARE SYNTHETIC PEPTIDES COMPRISING THE RESIDUES 75-84 OF HLA-B2702, A MOLECULE KNOWN TO LINK VCAM-1, AN ADHESION MOLECULE EXPRESSED IN VULNERABLE ATHEROSCLEROTIC PLAQUE. THE AUTORADIOGRAPHY STUDIES SHOW THAT ALL TRACERS ACCUMULATE WITHIN ATHEROSCLEROTIC PLAQUE EXPRESSING VCAM- AND THAT. I-B2702 SHOWS THE BEST PLAQUE/CONTROL FIXATION RATIO.LA MALADIE CORONARIENNE REPRESENTE L'UNE DES PREMIERES CAUSES DE MORTALITE DANS LE MONDE. LA MEDECINE NUCLEAIRE CONSTITUE LA PRINCIPALE MODALITE D'IMAGERIE POUR LE DIAGNOSTIC ET LA PRISE EN CHARGE DE CETTE PATHOLOGIE. PERFUSION : ACTUELLEMENT, LES RADIOTRACEURS UTILISES EN PRATIQUE CLINIQUE SONT DES TRACEURS DE LA PERFUSION MYOCARDIQUE. LE THALLIUM-201, TRACEUR DE REFERENCE, PRESENTE UNE DOSIMETRIE ELEVEE. 99mTcN-NOET A ETE PROPOSE POUR SON REMPLACEMENT. CONTRAIREMENT AUX RESULTATS PRECEDEMMENT OBTENUS IN VITRO SUR DES CARDIOMYOCYTES, LE VERAPAMIL, UN INHIBITEUR CALCIQUE, N'INHIBE PAS LA FIXATION MYOCARDIQUE DE 99mTcN-NOET IN VIVO CHEZ LE CHIEN. CE RESULTAT EST EN ACCORD AVEC L'HYPOTHESE D'UNE FIXATION ENDOTHELIALE DE CE TRACEUR. D'AUTRE PART, LES ETUDES INDIQUENT QU'EN TANT QUE TRACEUR PUR DU DEBIT, 99MTCN-NOET PEUT ETRE UTILISE POUR APPRECIER LA VIABILITE TISSULAIRE MYOCARDIQUE SUR UN MODELE D'INFARCTUS CHRONIQUE DU MYOCARDE CHEZ LE RAT. ATHEROME : LA RUPTURE D'UNE PLAQUE D'ATHEROME VULNERABLE EST L'EVENEMENT RESPONSABLE DE LA MAJORITE DES ACCIDENTS CORONARIENS. LA SECONDE PARTIE DE CETTE THESE PORTE SUR L'EVALUATION DE NOUVEAUX RADIOTRACEURS POTENTIELS DE CES PLAQUES SUR UN MODELE EXPERIMENTAL DE LAPIN GENETIQUEMENT HYPERCHOLESTEROLEMIQUE. LES 4 TRACEURS EVALUES (B2702(R), B2702-I, B2702-TC ET TC-RAFT-B2702) SONT DERIVES D'UN PEPTIDE ISSU D'UNE MOLECULE DE CMH-I DECRIT POUR LIER VCAM-1, UNE MOLECULE D'ADHESION EXPRIMEE AU NIVEAU DES PLAQUES VULNERABLES. LES ETUDES AUTORADIOGRAPHIQUES INDIQUENT QUE LES 4 TRACEURS S'ACCUMULENT DANS LES PLAQUES D'ATHEROME EXPRIMANT VCAM-1 ET QUE C'EST I-B2702 QUI PRESENTE LE MEILLEUR RAPPORT DE FIXATION PLAQUE/REGION SAINE
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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