2,421 research outputs found

    Octahedron-based Projections as Intermediate Representations for Computer Imaging: TOAST, TEA, and More

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    This paper defines and discusses a set of rectangular all-sky projections that have no singular points, notably the Tesselated Octahedral Adaptive Spherical Transformation (or TOAST) developed initially for the WorldWide Telescope. These have proven to be useful as intermediate representations for imaging data where the application transforms dynamically from a standardized internal format to a specific format (projection, scaling, orientation, etc.) requested by the user. TOAST is strongly related to the Hierarchical Triangular Mesh pixelization and is particularly well adapted to situations where one wishes to traverse a hierarchy of images increasing in resolution. Because it can be recursively computed using a very simple algorithm it is particularly adaptable to use with graphical processing units

    Nanoscale fillers. Fillers for high oxygen permeability polymer films

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    A wide range of polymer film products are available with varying degrees of permeability to a variety of gases, from oxygen to water to aromatic species. The barrier properties are determined primarily by the choice of the matrix polymer, and fine tailoring can be introduced through the addition of filler materials such as inorganic platelets and polymer blend materials. It was identified that hollow and porous addition of such particles appears little studied. Gel particles were prepared by free radical emulsion polymerisation of styrene and DVB in presence of hydrophobic solvents. Porous particles were prepared by the surfactant free emulsion copolymerisation of VBC and DVB, followed by Friedel- Crafts alkylation to yield hypercrosslinked microporous nanoparticles. Porous and gel particles were added to polymer films and the oxygen permeability and mechanical properties of these films determined. It was found that the addition of hypercrosslinked microporous nanoparticles increased the oxygen permeability of the films up to 〜50 % when added at 40 wt% loading. Further to these studies, hollow nanoparticles were prepared by the emulsion phase ATRP of DVB when initiated by mPEG-6-PS inisurf in the presence of a hydrophobic solvent

    WorldWide Telescope in Research and Education

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    The WorldWide Telescope computer program, released to researchers and the public as a free resource in 2008 by Microsoft Research, has changed the way the ever-growing Universe of online astronomical data is viewed and understood. The WWT program can be thought of as a scriptable, interactive, richly visual browser of the multi-wavelength Sky as we see it from Earth, and of the Universe as we would travel within it. In its web API format, WWT is being used as a service to display professional research data. In its desktop format, WWT works in concert (thanks to SAMP and other IVOA standards) with more traditional research applications such as ds9, Aladin and TOPCAT. The WWT Ambassadors Program (founded in 2009) recruits and trains astrophysically-literate volunteers (including retirees) who use WWT as a teaching tool in online, classroom, and informal educational settings. Early quantitative studies of WWTA indicate that student experiences with WWT enhance science learning dramatically. Thanks to the wealth of data it can access, and the growing number of services to which it connects, WWT is now a key linking technology in the Seamless Astronomy environment we seek to offer researchers, teachers, and students alike.Comment: 4 pages, 2 figures, describes software available at worldwidetelescope.or

    PSICIC: Noise and Asymmetry in Bacterial Division Revealed by Computational Image Analysis at Sub-Pixel Resolution

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    Live-cell imaging by light microscopy has demonstrated that all cells are spatially and temporally organized. Quantitative, computational image analysis is an important part of cellular imaging, providing both enriched information about individual cell properties and the ability to analyze large datasets. However, such studies are often limited by the small size and variable shape of objects of interest. Here, we address two outstanding problems in bacterial cell division by developing a generally applicable, standardized, and modular software suite termed Projected System of Internal Coordinates from Interpolated Contours (PSICIC) that solves common problems in image quantitation. PSICIC implements interpolated-contour analysis for accurate and precise determination of cell borders and automatically generates internal coordinate systems that are superimposable regardless of cell geometry. We have used PSICIC to establish that the cell-fate determinant, SpoIIE, is asymmetrically localized during Bacillus subtilis sporulation, thereby demonstrating the ability of PSICIC to discern protein localization features at sub-pixel scales. We also used PSICIC to examine the accuracy of cell division in Esherichia coli and found a new role for the Min system in regulating division-site placement throughout the cell length, but only prior to the initiation of cell constriction. These results extend our understanding of the regulation of both asymmetry and accuracy in bacterial division while demonstrating the general applicability of PSICIC as a computational approach for quantitative, high-throughput analysis of cellular images

    Ensuring that the outcome domains proposed for use in burns research are relevant to adult burn patients:a systematic review of qualitative research evidence

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    Background There have been several attempts to define core outcome domains for use in research focused on adult burns. Some have been based in expert opinion, whilst others have used primary qualitative research to understand patients’ perspectives on outcomes. To date there has not been a systematic review of qualitative research in burns to identify a comprehensive list of patient-centred outcome domains. We therefore conducted a systematic review of qualitative research studies in adult burns. Methods We searched multiple databases for English-language, peer-reviewed, qualitative research papers. We used search strategies devised using the SPIDER tool for qualitative synthesis. Our review utilized an iterative three-step approach: (1) outcome-focused coding; (2) development of descriptive accounts of outcome-relevant issues; and (3) revisiting studies and the broader theoretical literature in order to frame the review findings. Results Forty-one articles were included. We categorized papers according to their primary focus. The category with the most papers was adaptation to life following burn injury (n = 13). We defined 19 outcome domains across the 41 articles: (1) sense of self; (2) emotional and psychological morbidity; (3) sensory; (4) scarring and scar characteristics; (5) impact on relationships; (6) mobility and range of joint motion; (7) work; (8) activities of daily living and self-care; (9) treatment burden; (10) engagement in activities; (11) wound healing and infection; (12) other physical manifestations; (13) financial impact; (14) impact on spouses and family members; (15) analgesia and side effects; (16) cognitive skills; (17) length of hospital stay; (18) access to healthcare; and (19) speech and communication. We suggest that sense of self is a core concern for patients that, to date, has not been clearly conceptualized in the burns outcome domain literature. Conclusions This outcome domain framework identifies domains that are not covered in previous attempts to outline core outcome domains for adult burn research. It does so with reference to existing theoretical perspectives from the sociology and psychology of medicine. We propose that this framework can be used as a basis to ensure that outcome assessment is patient-centred. Sense of self requires further consideration as a core outcome domain

    Chauffeur braking

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    An experienced driver will `feather' the brakes so as to unwind the suspension compliance and stop the vehicle with only just enough torque in the brakes to hold the vehicle stationary on any gradient, or against the residual torque from an automatic transmission’s torque converter. An optimal stopping problem that minimises the total jerk was formulated and solved. This model was extended by including a linear relationship between the brake pressure and the acceleration of the car where the coefficients are estimated by linear regression. Finally, a Kalman filter estimates the state of the car using the tone wheel
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