1,720,998 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
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
Disseminação da Leishmaniose em ambientes urbanos e síntese de análogos de cromanonas com potencial para atividade leishmanicida
Get PDFTese apresentada ao Programa de Pós-Graduação em Ciências Ambientais da Universidade do Extremo Sul
Catarinense para obtenção do título de Doutora em Ciências Ambientais.A leishmaniose é uma doença negligenciada comum em regiões tropicais e subtropicais do mundo, sendo causada por protozoários do gênero Leishmania. É transmitida para seres humanos e outros mamíferos através da picada de insetos vetores. Apresenta diferentes formas clínicas (visceral ou kala-azar, cutânea e mucocutânea) que dependem da espécie do parasita causador da doença e da resposta imune do hospedeiro. A doença vem sendo descrita em vários municípios brasileiros, apresentando mudanças no padrão de disseminação, inicialmente predominando em ambientes silvestres e rurais, e mais recentemente em centros urbanos de médio e grande porte. A leishmaniose possui tratamento, no entanto, a maioria dos medicamentos apresenta limitações, como: toxicidade, efeitos adversos, difícil administração e podem causar resistência ao parasita. Considerando estes fatores que perpassam por questões ambientais e saúde, o presente trabalho buscou analisar os fatores associados à disseminação da leishmaniose em ambientes urbanos e sintetizar compostos do tipo Calea spp. com potencial para a atividade leishmanicida. A primeira etapa da pesquisa
contou com análise sistemática e bibliométrica executadas no software StArt, contemplando todos os artigos originais e de revisão entre 1959 a 2021. Na busca dos artigos, foram utilizados três descritores: “leishmaniasis” AND “urban” AND “rural”. Foram avaliados 304 estudos, os quais indicam que os fatores associados à disseminação da leishmaniose em áreas urbanas estão inter-relacionados, envolvendo as diferentes formas clínicas da doença, desmatamento, presença de vetores, participação de diferentes reservatórios da doença, ocupação desordenada do espaço geográfico, condições sanitárias precárias e questões econômicas que favorecem as tendências migratórias humanas. A análise bibliométrica mostrou que a maioria dos estudos foram desenvolvidos no Brasil. O número de publicações, em geral, tem crescido ao longo dos anos, principalmente em 2021, sendo a maioria direcionada à área epidemiológica. A segunda etapa do trabalho buscou obter por síntese total o composto uniflorol-B e análogos, apontados na literatura com potencial atividade leishmanicida. A rota sintética contou com sete etapas: I) acetilação; II) rearranjo de Fries; III) ciclização; IV) redução; V) esterificação; VI) Morita-Bailys-Hilman e VII) Isomerização (via bromação). A estratégia utilizada para a concretizar a síntese do uniflorol-B foi a realização das duas últimas etapas. Os compostos foram avaliados in silico. A rota sintética proposta se mostrou eficiente, onde foi possível sintetizar o composto uniflorol-B de modo inédito e seus análogos. A avaliação in silico das propriedades físico-quimicas sugere que todos os compostos sintetizados apresentam boa predição de perfil de biodisponibilidade oral. A
avaliação in vitro preliminar de atividade leishmanicida tem apontado resultados promissores para dois compostos sintetizados (41 e 57), que motivam para a continuidade da investigação da atividade biológica dessas moléculas
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
Synthesis of mycosporin analogues by gold catalysis and evaluation of their photoprotective activities
No full textLe nombre de cancers et notamment de cancers photoinduits étant en augmentation, il est indispensable d’identifier de nouvelles molécules protectrices de type filtres UV, réparatrices vis-à-vis des altérations de l’ADN mais également favorisant la réponse pigmentaire. Les lichens sont des organismes originaux qui possèdent des qualités de résistance remarquables aux rayonnements solaires dues notamment à la production de métabolites photoprotecteurs tels que les mycosporines. A partir de ce motif structural original, nous avons synthétisé divers analogues par catalyse à l’or en utilisant un outil de la chimie théorique (TD-DFT) pour orienter les synthèses. Les premières évaluations de leurs propriétés physico-chimiques des molécules ont montré des activités prometteuses.For several years, melanoma is the cancer with 84,000 new cases per year in Europe, including over 7000 cases in France, in 2010. One of the major causes of this cancer is the excessive exposure to UV radiations and it has been suggested that UV-A may be the primary cause of sunlight-induced melanoma. Hence, sunscreens with a good absorption in the UV-A spectral range need to be developed with a good efficacy and photostability. Lichens are original sources for the development of new UV filters because they possess ability to absorb UV due to the presence of metabolites such as mycosporines or MAAs (mycosporines like aminoacid). Based on the general structure of mycosporines, we have synthesized various analogues of mycosporines using a gold-catalyzed strategy. To orientate the synthesis, we used the method of the quantum chemistry: TD-DFT (Time-dependent density functional theory). These products were analyzed for their UV profiles and some of them showed good absorbing properties in UVA range. The cytotoxicity assay showed no toxicity of all products evaluated
Development of a novel blood-brain-barrier permeable IRE1 inhibitors for adjuvant therapy in glioblastoma.
No full textLe glioblastome multiple est l’un des cancers primaires les plus agressifs et le traitement actuel, basé sur le protocole de Stupp, montre ses limites avec une survie médiane proche de 15 mois et une rechute quasi-systématique. Récemment, des études ont montrées la possibilité de resensibiliser les cellules cancéreuses à la chimiothérapie par l’utilisation de petites molécules actives sur IRE1, une protéine transmembranaire du réticulum endoplasmique. Cette protéine est activée en conditions de stress protéique, intrinsèques des cellules cancéreuses, et permet à la cellule de s’adapter aux différentes modifications physiologiques qu’elle peut subir, traitements pharmacologiques compris. Depuis quelques années, les recherches effectuées au sein de l’équipe PROSAC ont permis la découverte d’une molécule nommée Z4P. Cette dernière, capable de passer la barrière hémato-encéphalique, inhibe IRE1 et ses activités associées afin de resensibiliser les cellules de glioblastome à la chimiothérapie. Lorsque Z4P est utilisé en combinaison avec un agent de chimiothérapie, le Témozolomide, on observe sur des modèles murins xénogreffés de GB humain une diminution significative de la taille des tumeurs, sans rechute. Ce manuscrit relate le travail de thèse effectué pour l’étude des Relations Structure-Activité de Z4P afin de mieux comprendre son mode de liaison et d’en améliorer les propriétés physico-chimiques.Glioblastoma multiform is one of the most aggressive primary brain cancers and the current treatment, based on Stupp protocol, marginally improves survival (15 months) with near-systematic relapse. Recently, studies have shown the possibility to resensitize cancer cells to chemotherapy using small molecules active on IRE1, a transmembrane protein of the endoplasmic reticulum. This protein is activated under proteic stress, intrinsic conditions of cancer cells, and allows the cell to adapt to the various physiological modifications it may undergo, including pharmacological treatments. Recently, research conducted by the PROSAC team has led to the discovery of a small molecule named Z4P. This blood-brain-barrier permeable compound can inhibits IRE1 and its associated activities in order to resensitize glioblastoma cells to chemotherapy. When Z4P is used in combinaison with Temozolomide, a chemotherapy agent, we observe in murine models xenografted with human GB a significant decrease in tumor size, without relapse. This manuscript relates the work carried out on the Structure-Activity Relationships study of Z4P in order to better understand its binding mode and to improve its drug-likeness
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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