1,720,972 research outputs found
Cell collagen interaction in 3D networks: structural features and mechanical properties
No full textIntroduction: An attractive alternative to synthetic
scaffolds is represented by reconstituted collagen gels
populated by cells. Such devices possess noteworthy
advantages since the collagen is one of the most
important mammalian protein and the collagen gel itself
constitutes an environment to host cells which is closer
to the native one. Cell populated collagen gels have
been successfully employed in tissue engineering
applications, as well as model to study cell-collagen
interaction in 3D constructs. However, in order to
improve the physical/biological performance of the gels
and to better understand cell/collagen interactions,
quantitative relationships must be developed between
the cell constructs and their mechanical properties. Aim
of this work is to develop an experimental model to
evaluate how cell reconfigure collagen gel and modify
its mechanical behaviour
Testicular activity of Mos in the frog, Rana esculenta: a new role in spermatogonial proliferation
No full textMos is a MAPK kinase kinase with an expression that is highly
restricted to the gonads. Its function is mainly associated to the
meiotic metaphase II arrest occurring during female gametogenesis,
whereas to our knowledge, its role during spermatogenesis
has not yet clarified. In the present paper, we report the
isolation of c-mos cDNA and the identification of a 60-kDa Mos
protein from the testis of the anuran amphibian, Rana esculenta.
Both the transcript and the protein are always present at low
levels in the testis during the frog annual sexual cycle, with single
significant peaks of expression in March and May, respectively.
Mos is mainly localized in the cytoplasm of primary and
secondary spermatogonia (SPG). Therefore, we have used treatments
with ethane-dimethane sulphonate (EDS), which blocks
spermatogonial mitosis in frogs. Four days after a single EDS
injection, Mos expression in SPG highly increases concomitantly
with the temporary arrest of mitosis. From 8 to 28 days after
the injection, the normal proliferative activity of SPG is restored,
and Mos expression gradually decreases to control levels. These
results strongly indicate that the c-mos proto-oncogene exerts a
new role associated to the regulation of spermatogonial proliferation
Inhibition of the basal and oestradiol-stimulated mitotic activity of primary spermatogonia by melatonin in the testis of the frog, Rana esculenta, in vivo and in vitro
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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