97,297 research outputs found
Counterion distribution near a monolayer of variable charge density
No full textWe study the bromide counterion distribution near a solid-supported monolayer in the case of vanishing bulk electrolyte concentration by resonant X-ray reflectivity. The surface charge density of the monolayer was varied by using different molar ratios of the cationic Di-Octadecyl-Di-methyl-Ammonium-Bromide (DODAB) and the neutral Di-Palmitoyl-Glycero-Phosphocholine (DPPC). The analysis, either
based on a conventional box model with an additional counterion contribution, or based on an independent unbiased global optimization approach, yields a good agreement with the classical Poisson-Boltzmann theory for the salt-free case
Joshua Davis: Author of Spare Parts
Full text linkCitation: K-State First (2016). Joshua Davis: Author of Spare Parts [Flier]. Manhattan, Kansas: K-State First.Flyer advertising Joshua Davis's author talk at Kansas State University
Holographic and diffractive x-ray imaging using waveguides as quasi-point sources
No full textWe report on lensless nanoscale imaging using x-ray waveguides as ultra-small sources for quasi-point-like illumination. We first give a brief account of the basic optical setup, an overview of the progress in waveguide fabrication and characterization, as well as the basics of image formation. We then compare one-step holographic and iterative ptychographic reconstruction, both for simulated and experimental data collected on samples illuminated by waveguided beams. We demonstrate that scanning the sample with partial overlap can substantially improve reconstruction quality in holographic imaging, and that divergent beams make efficient use of the limited dynamic range of current detectors, regardless of the reconstruction scheme. Among different experimental settings presented, smallest source dimensions of 29 nm (horizontal) x 17 nm have been achieved, using multi-modal interference effects. These values have been determined by ptychographic reconstruction of a Ta test structure at 17.5 keV and have been corroborated by simulations of field propagation inside the waveguide
Steven Johnson Author Talk Poster
No full textK-State Book NetworkA poster advertising an author talk by Steven Johnson at Kansas State University on September 3, 2014. Steven Johnson's book "The Ghost Map" was the 2014-2015 common book
Non-iterative coherent diffractive imaging using a phase-shifting reference frame
No full textLensless imaging is a high potential and currently intensely targeted research goal, in view of those fields of applications for which aberration-free high-resolution lenses are not available, for example for x-ray imaging. A recently proposed (direct inversion) variant of lensless imaging combines the advantages of two classical routes toward lensless imaging, the high-resolution characteristics of iterative object reconstruction, and the direct and deterministic nature of holographic reconstruction. Here, we use a simple standard optical setup using visible wavelength, a lithographic test object and a phase-shifting reference object to demonstrate the approach. Importantly, we show that a phase-shifting reference object, instead of the absorption mask proposed earlier, is sufficient for object reconstruction. This is relevant in view of the much easier implementation in future x-ray applications
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
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
Expanding “Communities and Collections” in the K-State Research Exchange (K-REx) to benefit the K-State Community and Beyond
No full textKansas State University has used its institutional repository, the K-State Research Exchange (K-REx), to store and share its first year experience program, K-State First, and notably its common reading program, K-State First Book. We have done so with the aim that the accessibility and preservation of these documents ensures program stability, promotes engagement with first year programming, and provides the ability to foster growth,educational opportunities, and community building outside of K-State. Moving away from research concentrated repositories and taking a more holistic approach to scholarship, especially when realizing the pedagogical significance of collaborative campus programming, institutions can showcase, discover, preserve, and grow programs that shape campus communities and engagement.
This session will provide an overview of K-REx and spotlight the digital archive of the university’s first year experience program and common reading program, K-State First Book. We will discuss the benefits and challenges to expanding the purview of your repositories. We talkthrough the types of materials we decide to host in our repository and why we share what we do. We will also provide recommendations on new ways to evaluate what belongs in institutional repositories and how this diversity can benefit your program, your institution, the community, and others
Ready Player One Program Event Poster
No full textK-State Book NetworkA poster advertising an author talk by Ernest Cline at Kansas State University on October 10, 2013. Ernest Cline's book "Ready Player One" was selected as the 2013-2014 common book
Depolarization and decreased surface expression of K+ channels contribute to NSAID-inhibition of intestinal restitution
No full textNon-steroidal anti-inflammatory drugs (NSAIDs) contribute to gastrointestinal ulcer formation by inhibiting epithelial cell migration and mucosal restitution; however, the drug-affected signaling pathways are poorly defined. We investigated whether NSAID inhibition of intestinal epithelial migration is associated with depletion of intracellular polyamines, depolarization of membrane potential (Em) and altered surface expression of K+ channels. Epithelial cell migration in response to the wounding of confluent IEC-6 and IEC-Cdx2 monolayers was reduced by indomethacin (100μM), phenylbutazone (100μM) and NS-398 (100μM) but not by SC-560 (1μM). NSAID-inhibition of intestinal cell migration was not associated with depletion of intracellular polyamines. Treatment of IEC-6 and IEC-Cdx2 cells with indomethacin, phenylbutazone and NS-398 induced significant depolarization of Em, whereas treatment with SC-560 had no effect on Em. The Em of IEC-Cdx2 cells was: −38.5±1.8mV under control conditions; −35.9±1.6mV after treatment with SC-560; −18.8±1.2mV after treatment with indomethacin; and −23.7±1.4mV after treatment with NS-398. Whereas SC-560 had no significant effects on the total cellular expression of Kv1.4 channel protein, indomethacin and NS-398 decreased not only the total cellular expression of Kv1.4, but also the cell surface expression of both Kv1.4 and Kv1.6 channel subunits in IEC-Cdx2. Both Kv1.4 and Kv1.6 channel proteins were immunoprecipitated by Kv1.4 antibody from IEC-Cdx2 lysates, indicating that these subunits co-assemble to form heteromeric Kv channels. These results suggest that NSAID inhibition of epithelial cell migration is independent of polyamine-depletion, and is associated with depolarization of Em and decreased surface expression of heteromeric Kv1 channels.ID: S0006295207001931; M3: Article; Accession Number: S0006295207001931; Author: L.C. Freeman (b); Author: D.F. Narvaez (a); Author: A. McCoy (a); Author: F.B. von Stein (c); Author: S. Young (b); Author: K. Silver (a); Author: S. Ganta (b); Author: D. Koch (b); Author: R. Hunter (b); Author: R.F. Gilmour (c); Author: J.D. Lillich (a, ⁎); Affiliation: Department of Clinical Sciences, Kansas State University, Manhattan, KS 66506, United States; Affiliation: Department of Anatomy and Physiology, Kansas State University, Manhattan, KS 66506, United States; Affiliation: Department of Biomedical Sciences, Cornell University, Ithaca, NY 14853, United States; Keyword: Non-steroidal anti-inflammatory drugs; Keyword: Intestinal epithelial cells; Keyword: Membrane potential; Keyword: Potassium channels; Number of Pages: 12; Language: English;Source type: Electronic(1)http://search.ebscohost.com/login.aspx?direct=true&db=edselp&AN=S0006295207001931&site=eds-live&scope=sit
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