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Quantitative study of the thymus vascularization in dogs
No full textDurante a vida fetal e no período neonatal, o timo é órgão de grande importância imunológica e, anatomicamente é o maior órgão linfático e com alta atividade linfopoiética, constando como precursor da linfopoiese. No que diz respeito à irrigação do timo em cães, a literatura é escassa, visto que os autores quando se reportam ao assunto fazem-no na sua maioria de maneira genérica. Com isso, aspectos morfológicos como número de vasos, tamanho do órgão foram estudados considerando as variáveis sexo e faixas etárias. Para este estudo, foram utilizados 24 fetos de cães domésticos, sem raça definida, machos e fêmeas, divididos em quatro grupos etários. Os timos foram processados para o estudo da microscopia de luz, e as análises estereológicas foram realizadas utilizando o método do disector físico associado com o princípio de ConnEulor. O volume do órgão (Vref), comprimento, espessura e largura aumentaram gradativamente com o desenvolvimento, sendo maior nos machos do que nas fêmeas. As variáveis estereológicas analisadas (densidade de comprimento do vaso - Lv, comprimento do vaso - L, densidade de superfície de área - Sv, superfície de área - S, estimação da densidade numérica vascular ? Nv(vasc) número total de vasos no órgão - N (vasc) ), tiveram um aumento gradativo, sendo que o Lv foi maior nas fêmeas e as demais os machos apresentaram maior valor. Aumento na Nv(vasc) e N (vasc) foi observado nos animais do grupo IV.During phoetal life and neonatal period, the thymus is the organ that has a wide immunological relevance and, anatomically speaking is the largest lymphoid organ presenting high limphopoietic activity presented as the predecessor of limphopoiesis. The literature about thymus irrigation in dogs is scarce, becouse most authors refer to the subject in a general way. Then, morphological aspects as number, shape, size, irrigation, and quantitative were study considering sexy and differents ages of development of the dogs. To the study, were used twenty-four fetus of the mongrel domestics dogs, males and females, divided into four different well defined aged groups (fetus 30, 40, 50 and 60 days). The thymus were processed for the light microscopy study, and the stereological analyses were done using the physical disector method associated with the ConnEulor principle. The volume of the organ, length, thickness and wide increased gradually with the development, in males is great that female. The stereological variables analysed (length density ? Lv, length od vascullar ? L, surface area density ? Sv, surface area ? S, vascullar number density ? N.v(vasc) , and vascullar total number - N. (vasc) ), had the gradual high, the Lv was more in female and the others variables were more in males. The rise of N.v(vasc) and N. (vasc) was observed on the group four animals
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
Spatio-temporal expression of the vascular endothelial growth factor (VEGF system and EG-VEGF in the thymus of dogs
No full textO objetivo deste trabalho foi avaliar a expressão de fatores de crescimento responsáveis pelo processo vasculogênico durante o desenvolvimento e involução do timo em cães. Para este propósito, timos de fetos de cães (30, 40 50 e 60 dias de desenvolvimento), cães jovens (6 meses de idade) e cães adultos (1 ano de idade) foram coletados. Os tecidos foram analisados estereológicamente e submetidos à imunohistoquímica, PCR tempo real e western blot para os componentes do sistema VEGF (VEGF-A, VEGF-C, Flt-1, KDR e Flt-4) e endocrine gland-derived (EG)-VEGF. Pela estereologia, observamos um aumento no número dos vasos durante o desenvolvimento do órgão e uma diminuição durante a involução (p<0.05). Todos os componentes do sistema VEGF e do EG-VEGF foram detectados em todos os estágios durante o desenvolvimento e involução. As proteínas correspondentes foram localizadas nas células endoteliais e células epiteliais da região cortical e medular, sendo que o EG-VEGF foi observado apenas nas células epiteliais da região medular. A expressão do RNAm do sistema VEGF e do EG-VEGF apresentou um perfil tempo-dependente durante o desenvolvimento e involução. O sistema VEGF apresentou uma expressão constante durante o desenvolvimento e um aumento progressivo durante a involução, com exceção do KDR que se mostrou crescente durante todo o período de desenvolvimento e involução e do VEGF-C que apresentou alta expressão durante a involução. A expressão do RNAm do EG-VEGF foi crescente durante as fases estudadas, já a expressão da sua proteína foi alta no início do desenvolvimento do timo e diminui na involução, onde permanece praticamente constante durante todo o período. Nossos resultados sugerem que o sistema VEGF e o EG-VEGF possuem atividades biológicas similares nas glândulas endócrinas e diferentes papéis durante o desenvolvimento e involução, o qual pode ser especificado em estudos futuros. Possíveis funções incluem um efeito modulatório na vasculogênese tímica e microambiente, influenciando na diferenciação e proliferação de timócitos, maturação de células T, interação célula-célula e secreção de hormônios tímicos.The aim this study was therefore to evaluate the expression of growth factors responsible for the vasculogenic process throughout development and initial involution of the canine thymus. For that purpose, thymuses from fetuses (30, 40, 50 and 60 days), juvenile (6 months) and adult (1 year) dogs were collected. The tissues were examined stereologically and subjected to immunohistochemistry, Real Time PCR and western blot for components of the VEGF-system (VEGF-A, VEGF-C, Flt-1, KDR and Flt-4) and endocrine gland-derived (EG)-VEGF. By means of stereology, the total number of blood vessels increased during development and decreased during involution. These changes were statistically significant (p<0.05). All components of the VEGF-system and EG-VEGF were detected in all stages during development and involution. The corresponding proteins were localized in endothelial and epithelial cells of cortical and medullar regions, and EG-VEGF was detected only in epithelial cells of medular region. The VEGF-system and EG-VEGF protein and mRNA expression showed a specific time-dependent profile during development and involution. The VEGF system showed a constant expression during development and a progressive increase during involution, except KDR that showed increased during all development and involution and VEGF-C that showed high expression during involution. The EG-VEGF RNAm expression was increased during development and involution, but protein expression was high in early thymus development and decreased in involution, and remains constant during all period. Our results suggest that VEGF-system and EG-VEGF have similar biological activities in endocrine glands and different roles during thymus development and involution which have to be specified in further studies. Possible functions include a modulatory effect on thymic vasculogenesis and microenvironment, influencing thymocyte proliferation and differentiation, T-cell maturation, cell-cell interaction and thymic hormonal secretion
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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