1,721,121 research outputs found
Rhodamine phalloidin F-actin. Critical concentration versus tensile strength
No full textThe mechanic and elastic properties of rhodamine phalloidin F-actin were investigated as a function of the ionic strength and in the absence of Mg2+. By increasing ionic strength from 3 to 19 mM, critical concentration decreased from 146 to 36 nM and the yield strength increased from 5.6 pN to 28.6 pN. At the ionic strength of 12-13 mm, the elastic modulus by stretching increased by 330-430 kP·nm-1 up to the break point, where it was 38-44.2 MP. The work required to break the filament, 403-439 kJ·M-1 provides an estimate of the free energy of annealing of rhodamine phalloidin F-actin, the annealing constant being 2.8 x 1074 M-1
Scattering for the L2supercritical point NLS
Full text linkWe consider the 1D nonlinear Schrödinger equation with focusing point nonlinearity. "Point"means that the pure-power nonlinearity has an inhomogeneous potential and the potential is the delta function supported at the origin. This equation is used to model a Kerr-type medium with a narrow strip in the optic fibre. There are several mathematical studies on this equation and the local/global existence of a solution, blow-up occurrence, and blowup profile have been investigated. In this paper we focus on the asymptotic behavior of the global solution, i.e., we show that the global solution scatters as t → ±∞ in the L2 supercritical case. The main argument we use is due to Kenig-Merle, but it is required to make use of an appropriate function space (not Strichartz space) according to the smoothing properties of the associated integral equation
A nonlinear quantum walk induced by a quantum graph with nonlinear delta potentials
No full textWe study a nonlinear quantum walk naturally induced by a quantum graph with nonlinear delta potentials. We find a strongly ballistic spreading in the behavior of this nonlinear quantum walk with some special initial states
Quantum graphs and dimensional crossover: The honeycomb
Full text linkWe summarize features and results on the problem of the existence of Ground States for the Nonlinear Schrödinger Equation on doubly-periodic metric graphs. We extend the results known for the two-dimensional square grid graph to the honeycomb, made of infinitely-many identical hexagons. Specifically, we show how the coexistence between one-dimensional and two-dimensional scales in the graph structure leads to the emergence of threshold phenomena known as dimensional crossover
Fabrication of rice flour films reinforced with hemp hurd and loaded with grapefruit seed oil: A simple way to valorize agro-waste resources toward low cost materials with added value
No full textNovel biodegradable films based on rice flour loaded with hemp hurd powder and grapefruit seed oil, as a mixture of natural compounds with potential antimicrobial activity, were fabricated and morphologically analyzed. Mechanical and thermal analysis were correlated to the hemp hurd content showing that no increase in thermal stability occurred for the rice flour composite while a noticeable improvement in mechanical properties was achieved after the addition of hemp hurd (up to 300 % of the pure rice flour film for a reinforcement loading of 20 % wt). Barrier properties were then studied aiming of evaluating the effect of hemp hurd on water sorption and diffusion. The decrease in polar site of rice flour and the hydrophobic character of either hemp hurd or essential oil led to a reduction of either the sorption parameter (about 85 % with a hemp hurd amount of 20 %wt) or the diffusion one (up to 96 % with a hemp hurd amount of 20 %wt). Optical properties appeared to not be pretty sensitive to hemp hurd presence. The release of a grapefruit seed oil was then studied through a second-order model and correlated with the effect of hemp hurd loading
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
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