3,718 research outputs found

    A Web Portal Approach to Improving Higher Education Accessibility: CFNC.ORG

    Get PDF
    This purpose of this research is to document the initial development, evolution, and outcomes of a web portal, CFNC.org which was designed to provide a comprehensive college access program for North Carolina citizens. The initiative’s focus is to support five critical areas of access: (1) aspirations, (2) academic preparation, (3) application, (4) affordability, and (5) availability. In identifying critical success factors, the research will examine environmental issues and potential obstacles that could impact successful implementation of such a web portal. Diffusion of innovations (DOI) research can provide insight into the factors that might impact successful adoption of the CFNC.org web portal. One outcome measure of importance is the college-going rate. Other measures include trends in student accounts created, college admissions application submitted through the web portal, school counselors trained to use the web portal, and overall usage of the web portal

    Self-assembling DNA-caged particles: nanoblocks for hierarchical self-assembly

    Full text link
    DNA is an ideal candidate to organize matter on the nanoscale, primarily due to the specificity and complexity of DNA based interactions. Recent advances in this direction include the self-assembly of colloidal crystals using DNA grafted particles. In this article we theoretically study the self-assembly of DNA-caged particles. These nanoblocks combine DNA grafted particles with more complicated purely DNA based constructs. Geometrically the nanoblock is a sphere (DNA grafted particle) inscribed inside a polyhedron (DNA cage). The faces of the DNA cage are open, and the edges are made from double stranded DNA. The cage vertices are modified DNA junctions. We calculate the equilibriuim yield of self-assembled, tetrahedrally caged particles, and discuss their stability with respect to alternative structures. The experimental feasability of the method is discussed. To conclude we indicate the usefulness of DNA-caged particles as nanoblocks in a hierarchical self-assembly strategy.Comment: v2: 21 pages, 8 figures; revised discussion in Sec. 2, replaced 2 figures, added new reference

    Optimal self-assembly of finite shapes at temperature 1 in 3D

    Full text link
    Working in a three-dimensional variant of Winfree's abstract Tile Assembly Model, we show that, for an arbitrary finite, connected shape XZ2X \subset \mathbb{Z}^2, there is a tile set that uniquely self-assembles into a 3D representation of a scaled-up version of XX at temperature 1 in 3D with optimal program-size complexity (the "program-size complexity", also known as "tile complexity", of a shape is the minimum number of tile types required to uniquely self-assemble it). Moreover, our construction is "just barely" 3D in the sense that it only places tiles in the z=0z = 0 and z=1z = 1 planes. Our result is essentially a just-barely 3D temperature 1 simulation of a similar 2D temperature 2 result by Soloveichik and Winfree (SICOMP 2007)

    Binary pattern tile set synthesis is NP-hard

    Full text link
    In the field of algorithmic self-assembly, a long-standing unproven conjecture has been that of the NP-hardness of binary pattern tile set synthesis (2-PATS). The kk-PATS problem is that of designing a tile assembly system with the smallest number of tile types which will self-assemble an input pattern of kk colors. Of both theoretical and practical significance, kk-PATS has been studied in a series of papers which have shown kk-PATS to be NP-hard for k=60k = 60, k=29k = 29, and then k=11k = 11. In this paper, we close the fundamental conjecture that 2-PATS is NP-hard, concluding this line of study. While most of our proof relies on standard mathematical proof techniques, one crucial lemma makes use of a computer-assisted proof, which is a relatively novel but increasingly utilized paradigm for deriving proofs for complex mathematical problems. This tool is especially powerful for attacking combinatorial problems, as exemplified by the proof of the four color theorem by Appel and Haken (simplified later by Robertson, Sanders, Seymour, and Thomas) or the recent important advance on the Erd\H{o}s discrepancy problem by Konev and Lisitsa using computer programs. We utilize a massively parallel algorithm and thus turn an otherwise intractable portion of our proof into a program which requires approximately a year of computation time, bringing the use of computer-assisted proofs to a new scale. We fully detail the algorithm employed by our code, and make the code freely available online

    A Single Dose of Prednisolone as a Modulator of Undercarboxylated Osteocalcin and Insulin Sensitivity Post-Exercise in Healthy Young Men: A Study Protocol

    Get PDF
    Background: Undercarboxylated osteocalcin (ucOC) increases insulin sensitivity in mice. In humans, data are supportive, but the studies are mostly cross-sectional. Exercise increases whole-body insulin sensitivity, in part via ucOC, while acute glucocorticoid treatment suppresses ucOC in humans and mice.Objectives: A single dose of prednisolone reduces the rise in ucOC produced by exercise, which partly accounts for the failed increase in insulin sensitivity following exercise.Methods: Healthy young men (n=12) aged 18 to 40 years will be recruited. Initial assessments will include analysis of fasting blood, body composition, aerobic power (VO2peak), and peak heart rate. Participants will then be randomly allocated, double-blind, to a single dose of 20 mg of prednisolone or placebo. The two experimental trials will involve 30 minutes of interval exercise (90%-95% peak heart rate), followed by 3 hours of recovery and 2 hours of euglycaemic- hyperinsulinaemic clamp (insulin clamp). Seven muscle biopsies and blood samples will be obtained at rest, following exercise and post-insulin clamps.Results: The study is funded by the National Heart Foundation of Australia and Victoria University. Enrollment has already commenced and data collection will be completed in 2016.Conclusion: If the hypothesis is confirmed, the study will provide novel insights into the potential role of ucOC in insulin sensitivity in human subjects and will elucidate pathways involved in exercise-induced insulin sensitivity

    Elasticity of entangled polymer loops: Olympic gels

    Full text link
    In this note we present a scaling theory for the elasticity of olympic gels, i.e., gels where the elasticity is a consequence of topology only. It is shown that two deformation regimes exist. The first is the non affine deformation regime where the free energy scales linear with the deformation. In the large (affine) deformation regime the free energy is shown to scale as Fλ5/2F \propto \lambda^{5/2} where λ\lambda is the deformation ratio. Thus a highly non Hookian stress - strain relation is predicted.Comment: latex, no figures, accepted in PRE Rapid Communicatio
    corecore