1,720,955 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
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
Acción antiinflamatoria del acetato de cacalol sobre la vía de señalización de NF-KB activada por LPS
Get PDFLa inflamación es una respuesta biológica natural en donde interaccionan factores solubles celulares, diferentes poblaciones celulares del sistema inmune innato y adaptativo y otras poblaciones celulares como las células endoteliales. Este proceso puede surgir en cualquier tejido vascularizado en respuesta a estímulos externos (lesión traumática o infecciones) o internos (reacciones autoinmunes) que han lesionado su integridad. El proceso normalmente al control y resolución de la infección, a la recuperación tisular y la curación. La inflamación parece estar diseñada para funcionar en microambientes tisulares de forma rápida y aislada. Las vías de señalización intracelular que activan a las células que participan en la reacción inflamatoria requieren de la activación del sistema del control transcripcional NF-ΚB. En ocasiones esta respuesta puede alterarse produciendo daño permanente y consecuencias patológicas asociadas con enfermedades cardiovasculares, respiratorias, digestivas o autoinmunes. Un caso extremo se presenta durante el choque séptico en donde deja de haber procesos locales y la inflamación se convierte en un proceso sistémico. La presentación de formas descontroladas de la inflamación han llevado a la búsqueda y desarrollo de compuestos capaces de interferir con el proceso inflamatorio diferentes niveles. Existe un gran número de fármacos antiinflamatorios, esteroideos y no esteroideos, los cuales ejercen su acción farmacológica mediante el bloqueo de moléculas mediadoras de la iniciación y amplificación de la respuesta inflamatoria. Sin embargo, se ha reportado que, independientemente de la naturaleza esteroidea o no esteroidea de los fármacos antiinflamatorios, cuando se consumen por periodos largos pueden generar efectos adversos, lo cual justifica la búsqueda de nuevos compuestos antiinflamatorios. México cuenta con gran variedad de especies vegetales con diferentes usos medicinales. Psacalium decompositum se usa en la medicina tradicional como antidiabética y antiinflamatoria. Entre los principales compuestos identificados en P. decompositum se encuentra el cacalol el cual se ha reportado que presenta actividad antinflamatoria en modelos de inflamación aguda. Así mismo se ha reportado que el compuesto es muy fácil de oxidar, pero, al acetilarlo en su grupo OH su estructura se vuelve es más estable, produciendo acetato de cacalol (CA). Sin embargo, poco se ha avanzado en el conocimiento de las actividades de este compuesto y del mecanismo de acción antiinflamatoria que podría presentar.Inflammation is a natural biological response in which soluble cellular factors, different populations of the innate and adaptive immune response in others cells type, such the endothelial cells interact. This process can arise in any vascularized tissue in response to external stimuli (traumatic injury or infections) or internal stimuli (autoimmune reactions) that have damaged its integrity. Inflammation is designed to function within the tissue-microenvironment to provide a local and insolated response. The signaling pathway activated in this cells populations is NF-ΚB system. The process normally leads to recovery from infection and healing. Sometimes this response can be altered, producing permanent damage and pathological consequences associated with cardiovascular, respiratory, digestive or autoimmune diseases. A extreme case occurs during septic shock were the local effect becomes systemic. There is a large number of steroidal and non-steroidal anti-inflammatory drugs, which exert their pharmacological action by blocking molecules that mediate the initiation and amplification of the inflammatory response. However, it has been reported that, regardless of the steroidal or non-steroidal nature of anti-inflammatory drugs, when consumed for long periods of time they can generate adverse effects, which justifies the search for new anti-inflammatory compounds. Mexico has a great variety of plant species with different medicinal uses. Psacalium decompositum is used in traditional medicine as both an antidiabetic and anti-inflammatory. Among the identified compounds in P. decompositum the main is cacalol, which has been reported to have anti-inflammatory activity in acute inflammation models. Likewise, it has been reported that the compound is very easy to oxidize, but, when acetylated in its OH group, its structure becomes more stable, producing cacalol acetate (CA). However, little progress has been made in understanding the activities of this compound and the mechanism of anti-inflammatory action that it could present
Actividad anti-inflamatoria de compuestos sesquiterpénicos aislados de Psacalium decompositum (Gray) Rob. & Brett. en modelo de TPA y en la línea celular de macrófagos RAW 264.7
Get PDFInflammation is an adaptative response, triggered by various harmful stimuli, its aim is to eliminate injurious agents, as well as the restoration and normal functioning of the affected tissue or organ. However, this response can be altered and produce permanent damage, which often have pathological consequences, like cardiovascular, respiratory, digestive or autoimune diseases. For this reason, there is a large number of anti-inflammatory drugs nowadays, such as esteroideal and non-steroideal drugs, they have pharmacological action mainly by blocking initiation and amplification mediators of the inflammatory response. It has been reported, nevertheless, that the consumption of anti-inflammatory drugs for long periods may cause adverse effects, which brings us to the pursuit of new anti-inflammatory compounds. Mexico is a country with a very large variety of plant species with diverse medicinal uses, an example of this is Psacalium decompositum, a plant with diverse uses in traditional medicine, among which its antidiabetical and anti-inflammatory properties stand out. Among the main compounds that have been identified in P. decompositum, are cacalol and a rich in fructooligosaccharides (FOS) fraction. It remains unknown if this compounds are responsible for anti-inflammatory action.Objective. Determine the anti-inflammatory activity of the cacalol, cacalol acetate and the fraction rich in fructooligosaccharides of Psacalium decompositum in RAW 264.7 macrophages. Materials and methods. For the in vivo model, male mice of the CD-1 strain were used to induce topical inflammation by the administration of TPA (2.5 μg) in the ear and subsequently the compounds cacalol, cacalol acetate and the fraction FOS as well as the hexanic extract and the aqueous extract (1 μg/ear). For the in vitro study, RAW 264.7 macrophages were cultured and stimulated with LPS (5 μg/mL) to induce an inflammatory response an inflammatory response and subsequently treated at different times (15, 30, 60, 90 and 240 minutes) with the compounds cacalol (100 µM), cacalol acetate (100 µM), the FOS fraction (1µg/mL) and the aqueous extract (10 μg/mL), using dexamethasone as positive control (50 µM). After the treatments, the expression of the TNF- α, IL-6, IL-1β, IL-10 and COX.2 mRNAs was assessed by qPCR, cytokine concentrations (TNF-α, IL-6, IL-1β, IL-10) were measured in the culture medium by the ELISA method and phosphorylation of p65 subunit of NF-κB by the ELISA method. Results. The results showed that both cacalol and cacalol acetate significantly inhibited the development of ear edema by up to 40% compared to the control (only treated with vehicle), unlike the hexanic extract that inhibited 39.2% and the FOS fraction which only inhibited it by 28%. Furthermore, in RAW 264.7 macrophages the compounds significantly decreased the expression of TNF-α, IL-6 and IL-1β, as well as their concentrations in the culture medium. No changes were detected in the expression or concentration of IL-10. The concentrations of the phosphorylated p65 subunit decreased with the extracts and with the isolated compounds.Conclusion. Cacalol, cacalol acetate, as well as the FOS fraction and hexane and aqueous extract, reduce inflammation through the modulation of inflammatory cytokines, suppressing the pro-inflammatory ones; however, they do not modify anti-inflammatory citokines. This effects could be involved in the inhibition of the NF-κB pathway as it decreases the level of the phosphorylated p65 subunit. Even so, it is necessary to continue the study with the transcription factors involved in the regulation of these cytokines.La inflamación es una repuesta adaptativa que se desencadena por diversos estímulos nocivos y cuyo objetivo es la eliminación de un agente dañino, así como el restablecimiento y funcionamiento normal del tejido u órgano afectado. Esta respuesta puede alterarse produciendo daño permanente y consecuencias patológicas asociadas con enfermedades cardiovasculares, respiratorias, digestivas o autoinmunes. Hoy en día existe un gran número de fármacos antiinflamatorios, esteroideos y no esteroideos, los cuales ejercen su acción farmacológica mediante el bloqueo de moléculas mediadoras de la iniciación y amplificación de la respuesta inflamatoria. Sin embargo, se ha reportado que, independientemente de la naturaleza esteroidea o no esteroidea de los fármacos antiinflamatorios, cuando se consumen por periodos largos pueden generar efectos adversos, lo cual justifica la búsqueda de nuevos compuestos antiinflamatorios. México cuenta con gran variedad de especies vegetales con diferentes usos medicinales. Psacalium decompositum se usa en la medicina tradicional como antidiabética y antiinflamatoria. Entre los principales compuestos identificados en P. decompositum se encuentran el cacalol y una fracción rica en fructooligosacáridos (FOS), los cuales se han reportado con actividad antinflamatoria en modelos de inflamación aguda y en modelo de síndrome metabólico respectivamente. Sin embargo, se desconoce el mecanismo por el cual estos compuestos ejercen su acción antiinflamatoria.Objetivo. Determinar la actividad antiinflamatoria del cacalol, acetato de cacalol y la fracción rica en fructooligosacáridos de Psacalium decompositum en macrófagos RAW 264.7. Materiales y métodos. Para el modelo in vivo se utilizaron ratones machos de la cepa CD-1, a los que se les indujo inflamación tópica mediante la administración de TPA (2.5 µg) en la oreja; posteriormente se administraron los compuestos cacalol, acetato de cacalol y la fracción FOS, así como el extracto hexánico y el extracto acuoso (1 µg/oreja). Para el estudio in vitro se cultivaron macrófagos de la línea RAW 264.7, los cuales fueron estimulados con LPS (5 µg/mL) para inducir una respuesta inflamatoria; posteriormente se trataron por diferentes tiempos (15, 30, 60, 90 y 240 minutos), con los compuestos cacalol (100 µM), acetato de cacalol (100 µM) y la fracción FOS (1 µg/mL), así como el extracto hexánico (10 µg/mL) y el extracto acuoso (10 µg/mL), utilizando como control positivo dexametasona (50 µM). Al final de los tratamientos la expresión del ARNm de TNF-α, IL-6, IL-1β, IL-10 y COX-2 se midió por qPCR; las concentraciones de las citocinas TNF- α, IL-6, IL-1β e IL-10 en el medio de cultivo y la fosforilación de la subunidad p65 de NF-κB se determinaron por el método de ELISA. Resultados. Los resultados mostraron que tanto el cacalol como su acetato inhibieron significativamente el desarrollo del edema auricular en un 40% con respecto al control (vehículo), el extracto hexánico lo inhibió en un 39.2% y la fracción FOS en un 28%. En macrófagos RAW 264.7 los compuestos disminuyeron significativamente la expresión de TNF-α, IL-6 e IL-1β, así como sus concentraciones en el cultivo. No se detectaron cambios en la expresión ni en la concentración de IL-10. La concentración de la subunidad p65 fosforilada disminuyó con los extractos y con los compuestos aislados. Conclusión. El cacalol, el acetato de cacalol, la fracción FOS y los extracto hexánico y acuoso redujeron la inflamación y suprimieron las concentraciones de citocinas proinflamatorias, sin afectar las antiinflamatorias, lo cual podría estar relacionado con inhibición de la vía NF-κB, ya que los nivel de la subunidad de p65 fosforilada fueron reducidos. Es necesario continuar el estudio de losfactores de transcripción implicados en la regulación de dichas citocinas
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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