117,624 research outputs found
Teste de ligação à zona pelúcida: avaliação de dois métodos para contagem de espermatozóides.
No full textA zona pelúcida é a maior barreira que o espermatozóide precisa ultrapassar para que possa penetrar e fecundar um oócito. Somente os espermatozóides capacitados e com membrana íntegra podem se ligar à zona, sofrer a reação do acrossoma e fecundar. Portanto, a avaliação da interação do espermatozóide com a zona pelúcida é considerado um teste funcional para avaliar a fertilidade de uma amostra de sêmen. O presente estudo teve por objetivo avaliar a ligação à zona utilizando dois métodos para contagem de espermatozóides: microscopia de constraste de fase (CF) e microscopia de epifluorescência (FL)
Effect of sex on survival of bovine in vitro produced embryos vitrified by Cryotop.
No full textProceedings of the 31st Annual Meeting of the Brazilian Embryo Technology Society (SBTE); Cabo de Santo Agostinho, PE, Brazil, August 17th to 19th, 2017. Abstract
Anatomy of bark of Populus tremula L. and P. davidiana Dode in relation with their systematics
No full textThe data of comparative-anatomical study of structure of stem bark of two vicarious species (Populus tremula L. and P. davidiana Dode) are represented in this article. Methodic of the study was traditional in anatomy of plants. It was established that having a great similarity in the structure of the bark, which is justified by belonging to the same genus of Populus L., nevertheless studied species differ clearly on the anatomical features of the bark. In particular, P. davidiana different from P. tremula by heterogeneous phellem in young stems, lack of sclereids in the primary bark, the formation of sclerenchyma already in the secondary phloem of one-year stem, as well as by lack of sclereids in secondary phloem in the bark of the trunk region
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Square Dancing with the Stars to Enhance Dynamic Hirschman Linkages?
No full textIn this Presidential Address, the author takes the reader on a reconnaissance of his life and time as a regional scientist. He points out scenery he found scintillating along the way, hoping that some may pick up the banner and chew on a few of the ideas for a while. He suggests a revisit to Albert O. Hirschman’s notion of key sectors and more empirical analysis related to Marcus Berliant’s and Masahisa Fujita’s notion of knowledge creation and transfer.Presidential Address, San Antonio, Texas, March 29, 2014 (53rd Meetings of the Southern Regional Science Association
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
Effect of insulin-transferrin-selenium (ITS) and L-ascorbic acid (AA) during in vitro maturation on in vitro bovine embryo development.
No full textDesenvolvimento de embriões clones a partir de fibroblastos de bovino adulto transfectados ou não.
No full textApresentado também no evento: CONGRESSO NACIONAL DE GENÉTICA, 49., 2003, Águas de Lindóia. A dupla hélice do DNA: anais. Águas de Lindóia: Sociedade Brasileira de Genética, 2003. Autores: Iguma, L. T.; Melo, E. O.; Sousa, R. V.; Campos, H. da C. F.; Franco, M. M.; Dode, M. A. N.; Rech, E.; Rumpf, R
Letter from unknown writer to Jesse L. Boyce
No full textLetter to Jesse L. Boyce from unknown author (possibly Jack) about the investigation into the powder magazine located in the Grand Canyon. Some personal news is included in the letter such as the writer's marriage to the daughter of C.A. Taylor, former Supervisor of Cochise County
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
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