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Pressure Dependence of the Frequency Permeability Spectra of Soft Ferrite Composite Materials: A Method of Measuring the Natural Ferromagnetic Resonance Frequency
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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
Anticorps anti-récepteur NMDA dans les premiers épisodes psychotiques
Get PDFSchizophrenia is a severe disease whose etiopathogenic mechanisms remaining poorly understood. The autoimmune hypothesis in psychosis is supported by many studies. Peripheral inflammation or low-grade neuroinfammation may contribute to glutamatergic NMDA receptor hypofunction which is a core mechanism in schizophrenia. Anti-NMDA receptor limbic encephalitis is an outstanding topic to study the role of autoimmune process in the genesis of psychotic symptoms. This condition is associated with specific IgG anti-NR1 in CSF inducing NMDA receptor diffusion ouf of the synapse and endocytosis. Isolated psychiatric form of the disease or anti-NMDA-R antibodies detection in the sera of schizophrenic cases may suggest that some schizophrenic patients could be considered as mild-encephalitis. In our study, 5 patients (12.5%) of 40 with a first-episode of psychosis were seropositive for IgG anti-NR1 validating precedent studies in schizophrenia. While the pathogenic effects are clearly demonstrated in encephalitis, the involvement of these markers in the genesis of psychotic symptoms in schizophrenia is debated and their pathogenicity remains to be established. The identification of clinical or paraclinical features in carriers could provide new therapeutic approach aiming pathogenic mechanisms.La schizophrénie est une pathologie sévère dont les mécanismes étiopathogéniques restent mal connus. L’hypothèse de mécanismes auto-immuns pathogènes dans les psychoses est confortée par de nombreux travaux. Une inflammation périphérique ou une neuroinflammation de bas grade sont susceptibles de contribuer à l’hypofonctionnement du récepteur glutamatergique NMDA qui est un mécanisme central dans la schizophrénie. Les encéphalites à anticorps anti-récepteur NMDA constituent un sujet passionnant pour étudier le rôle de processus auto-immuns dans la genèse de symptômes psychotiques. Cette maladie est associée de façon spécifique à des IgG anti-NR1 dans le LCR, induisant une diffusion hors de la synapse et une endocytose du récepteur. L’existence de formes psychiatriques pures et de ces anticorps dans le sérum de patients schizophrènes suggèrent que certains cas de schizophrénies pourraient être considérés comme des encéphalites frustres. Dans notre étude, 5 patients (12,5%) sur 40 ayant un premier épisode de psychose présentaient des IgG anti-NR1 sériques, confirmant les résultats de précédentes études réalisées dans la schizophrénie. Alors que les effets pathogènes sont bien démontrés dans les encéphalites, l’implication de ces marqueurs dans la genèse des symptômes psychotiques dans la schizophrénie est débattue et leur pathogénicité doit être établie. L’identification de caractéristiques cliniques ou paracliniques chez les individus qui en sont porteurs pourraient permettre de proposer des thérapeutiques plus proches des mécanismes étiopathogéniques en cause
Development and realization of magnetodielectric materials for antenna miniaturization in the UHF band
No full textLa miniaturisation des antennes s'accompagne d'une dégradation leurs performances (bande passante, gain, efficacité), surtout avec l'utilisation de substrats matériaux diélectriques. Pour relever le défi « intégration / performances », la conception de nouveaux matériaux tels que les ferrites magnétoélectriques constitue une alternative des plus prometteuses. Ce travail met en avant les principaux paramètres à l'élaboration de ferrite spinelle par coprécipitation. Un traitement thermique modéré a permis l'obtention de céramiques semi poreuses pour la montée en fréquence. En parallèle, l'anisotropie magnétocristalline, liée à la composition (rapport Nickel / Zinc, Cobalt, Fer 2+…) ; ainsi que l'anisotropie magnétoélastique lors de l'application d'une contrainte, étendent encore le domaine des faibles pertes des ferrites de Nickel-Zinc de 400 MHz à plus de 1 GHz. Ces matériaux ont ainsi pu équiper des antennes sur les fréquences du DVH-H (470 – 830 MHz) et répondent aux normes du DVB-H. De façon à profiter pleinement de la miniaturisation, nous avons proposé une antenne imprimée. Une bonne corrélation est trouvée entre les résultats de simulation et de mesure, ainsi que des relations adaptées aux antennes patch. Enfin dans le domaine émergent des communications On / Off bodies, nous avons développé des antennes flexibles sur un substrat de type PDMS. Pour assurer une bonne efficacité de l'antenne, celle-ci est encapsulée, ce qui évite une métallisation hasardeuse (fissures, manque d'adhérence).Antenna miniaturization, especially with dielectric substrates, is accompanied by a radiation loss (bandwidth, gain, efficiency). To meet the challenge "integration / performance", the design of new materials such as magnetodielectrics ferrites is a promising alternative. To satisfy these requirements, this work highlights the main parameters of ferrite spinel development by coprecipitation. A moderate thermal treatment leads to semi porous ceramics. In parallel, the magnetocrystalline anisotropy, related to the composition (ratio Nickel / Zinc, Cobalt, Iron 2+ ...), and the magnetoelastic anisotropy with application of stress, extend the field of low-loss from 400 MHz to over 1 GHz, in the Nickel-Zinc ferrite. These materials were able to equip antennas on DVH-H frequencies (470-830 MHz). In order to take full advantage of miniaturization, we proposed a printed antenna. A good correlation between simulation results and measurement is obtained, together with relations adapted to patch antennas. Finally, in the emerging field of communications On / Off bodies, we have developed flexible antennas on PDMS substrate. To ensure good antenna efficiency, it is encapsulated, thereby avoiding a hazardous metallization (cracks, loss of adhesion)
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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