1,721,017 research outputs found
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
Confined cavitation: an experimental study
Full text linkThe behavior of a cavitation bubble is greatly influenced by its surroundings. In an unbounded liquid a cavitation bubble grows and collapses spherically but a nearby solid boundary changes everything. Now the bubble collapses towards the wall and looses its spherical shape. During collapse a thin jet is formed piercing through the center of the bubble aimed towards the wall. Upon impacting on the boundary the jet spreads out radially exerting a strong shear stress on the wall. The shear strength drops with a -11=4 power law. The strength of the jet depends strongly on the starting distance between the bubble and the wall. The jet impact velocity increases the closer the bubble gets to the wall up to a maximum for a standoff distance of about » 0.6. For bubbles closer than that the jet velocity decreases. This jet flow can be utilized to temporarily porate the membranes of living cells; adherent cells are grown on the wall of a culture flask and exposed to a single cavitation bubble. As the jet impacts on the cell monolayer it detaches cells in a circular region around the point of impact. Surrounding the cleared area there is a ring where the shear stress was to weak to detach the cells but strong enough to rip small holes in the cell membrane. This permeabilization of the membrane can be detected by adding a dye to the liquid such that only the porated cells will be stained. Afterwards the cells are tracked for an entire day to make sure they survive the treatment. Interestingly enough when a bubble is created with a standoff distance smaller than ° = 0.6 the amount of stained cells keeps increasing while the circular detachment area shrinks. The cause for this is the bubble growth on top off the surface which is also strong enough to porate cells. This finding can be used for instance in microfluidics. If a bubble is created in a thin liquid film between two parallel plates the bubble takes on a flat pancake like shape. This quasi 2-dimensional bubble grows and collapses in a circular fashion and no jets are formed. But as was shown before bubble growth across a surface can also porate cells and by growing cells on one of the two walls in such a system this was also proven the case in microfluidics. Cells in suspension can also be porated but during bubble growth they take on a ”tear” shape which is expected to be a result of entraining the cell from the boundary layer into the main flow. A way to circumvent this instability we created a second bubble on the other side of the cell. The cell becomes compressed and simultaneously sheared yet it remains in place. Bubbles in confined geometries jet in the presence of a channel wall; even when a small channel opening is present. By positioning the bubble such that the jet does not impact on the wall but flows into the a channel opening realizes a pump. This idea which was put forward for larger millimeter sized bubbles by Khoo’s group (Khoo, et.al. 2005) has now been for the first time realized on the microscale for lab on a chip devices. Similar to the step from 3D to 2D the addition of second side wall close the first side wall takes us from 2D to a quasi 1-dimensional bubble. A bubble generated in such a long and thin channel only grows and collapses in the lengthwise direction of the channel. A one dimensional model does indeed describe the bubble dynamics quite accurately but only if the temperature inside the bubble is taken into account. This time another solid boundary will not induce jetting in the bubble. A free interface close to the jet however does result in a jet. It is however not a jet penetrating through the bubble but the result of the rapidly growing bubble pushing liquid out of the open end of the channel. We demonstrate on demand and reproducible jetting on the micrometer scale with more than 100 m/s
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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