1,721,060 research outputs found
Sidestream dark field videomicroscopy for in vivo evaluation of vascularization and perfusion of mammary tumors in HER-2/neu transgenic mice.
No full textAngiogenesis plays a key role in tumor growth and formation of metastases. Angiogenesis inhibitors and anti-vascular agents may prove useful in the treatment of breast cancer. A comprehensive characterization of the vasculature and perfusion of mammary tumors is a prerequisite for developing new specific drugs. We applied sidestream dark field videomicroscopy to evaluate in vivo the vascular network of spontaneous mammary tumors in HER-2/neu transgenic mice. The tumor masses showed higher vessel density as compared to the healthy mammary gland (total vessel density of 16.8 [13.4-20.5] mm/mm(2) versus 9.1 [8.1-10.9] mm/mm(2) , p<0.001). Tumor vessel density was reduced in mice treated with the anti-angiogenesis agent berberine (total vessel density of 12.1 [10.6-13.1] mm/mm(2) ). SDF imaging is a versatile technique that may be useful for understanding the role of angiogenesis in the progression of breast cancer and its relationship with outcome. It may represent a valuable tool for a dynamic monitoring of the effects of new anti-angiogenesis therapies. This article is protected by copyright. All rights reserved
Going 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
Gestione dell’energia radiante nelle piante da frutto: utilizzazione, foto-protezione e foto-danno. Quali implicazioni per la produttività?
No full textThe energetic basis of orchard productivity lies in the interaction between the tree and sunlight. The light intercepted by a plant is linearly related to the amount of dry matter it produces. This concept drew the evolution of the new, intensive orchard planting systems, although this dependence seems to be more subordinate to planting system rather than light intensity. At whole plant level not always the increase of irradiance determines productivity improvement. One of the reasons can be the plant intrinsic un-efficiency in using energy. Generally in full light only the 5–10% of the total incoming photosynthetic photon flux density (PPFD) is allocated to net photosynthesis. Therefore preserving or improving this efficiency becomes pivotal for scientist and fruit growers. Net photosynthesis increases with light until the saturation point and additional PPFD doesn’t improve carboxylation. In several parts of the world, under clear sky the PPFD reaches commonly 2000 μmol photons m-2 s-1 or above, and about 50% of the incoming light is enough for reaching the saturating point in most plant species. On the other hand, about half of the available light may be in excess. Even tough a conspicuous energy amount is reflected or transmitted, plants can not avoid to absorb photons in excess. The chlorophyll over-excitation promotes the reactive oxygen species (ROS) production increasing the photoinhibition (photo-damage) risks. The dangerous consequences of photoinhibition forced plants to evolve a complex and multilevel machine able to dissipate the energy excess quenching heat (Non Photochemical Quenching), moving electrons (water-water cycle, cyclic transport around PSI, glutathione-ascorbate cycle and photorespiration) and scavenging the generated ROS. The price plants must pay for this equipment is the use of CO2 and reducing power with a consequent decrease of the photosynthetic efficiency, both because some photons are not used for carboxylation and an effective CO2 and reducing power loss occurs. The wide photo-protective apparatus, although is not able to cope with the excessive incoming energy, therefore photo-damage occurs. Each event increasing the photon pressure and/or decreasing the efficiency of the described photo-protective mechanisms (i.e. thermal stress, water and nutritional deficiency) can emphasize the photoinhibition. Likely in nature a small amount of not damaged photo-systems is found because of the effective, efficient and energy consuming recovery system. Since the damaged PSII is quickly repaired with energy expense, it would be interesting to investigate how much PSII recovery costs to plant productivity.
This review purposes to improve the knowledge about the several strategies accomplished for managing the incoming energy and the light excess implication on photo-damage in plants. Furthermore the chlorophyll fluorescence measure technique is described. This is the most useful method, particularly because it can be used in vivo as well and it is possible to quantify and discriminate the contribution of pathways in which the incoming photon pressure is engaged. Finally some cases of light excess linked with abiotic stresses and particular physiological condition on fruit species are reported
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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