1,720,999 research outputs found
A Phenomenological Description of BslA Assemblies Across Multiple Length Scales
No full textIntrinsically interfacially active proteins have garnered considerable interest recently due to their
potential use in a range of materials applications. Notably, the fungal hydrophobins are known to
form robust and well organized surface layers with high mechanical strength. Recently it was shown
that the bacterial biofilm protein BslA also forms highly elastic surface layers at interfaces. Here we
describe several self-assembled structures formed by BslA, both at interfaces and in bulk solution,
over a range of length scales spanning from nanometers to millimeters. First, we observe transiently
stable and highly elongated air bubbles formed in agitated BslA samples. We study their behavior
in a range of solution conditions and hypothesize that their dissipation is a consequence of the slow
adsorption kinetics of BslA to an air/water interface. Second, we describe elongated tubules formed
by BslA interfacial films when shear stresses are applied in both a Langmuir trough and rheometer.
These structures bear a striking resemblance, although much larger in scale, to the elongated air
bubbles formed during agitation. Taken together, this knowledge will better inform the conditions
and applications of how BslA can be utilized in the stabilization of multiphase materials
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
Density and temperature controlled fluid extraction in a bacterial biofilm is determined by poly-gamma-glutamic acid production
No full textA hallmark of microbial biofilms is the self-production of extracellular matrix that encases the cells resident within the community. The matrix provides protection from the environment, while spatial heterogeneity of expression influences the structural morphology and colony spreading dynamics. Bacillus subtilis is a model bacterial system used to uncover the regulatory pathways and key building blocks required for biofilm growth and development. Previous reports have suggested that poly-gamma-glutamic acid (PGA) production is suppressed during biofilm formation and does not play a major role in biofilm morphology of the undomesticated isolate NCIB 3610. In this work we report on the observation of multiple travelling fronts that develop during the early stage of B. subtilis colony biofilm formation. We find the emergence of a highly motile population of bacteria that is facilitated by the extraction of fluid from the underlying agar substrate. Motility develops behind a moving front of fluid that propagates from the boundary of the biofilm towards the interior. The extent of proliferation is strongly modulated by the presence of extracellular polysaccharides (EPS). We trace the origin of this moving front of fluid to the production of PGA. We find that PGA production is correlated with higher temperatures, resulting in a mature biofilm morphology that is distinct from the biofilm architecture typically associated with B. subtilis. Our results suggest that B. subtilis NCIB 3610 produces distinct biofilm matrices in response to environmental conditions.DataDescription.xls
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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