545 research outputs found

    Translating a Regular Grid over a Point Set

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    We consider the problem of translating a (finite or infinite) square grid G over a set S of n points in the plane in order to maximize some objective function. We say that a grid cell is k-occupied if it contains k or more points of 5. The main set of problems we study have to do with translating an infinite grid so that the number of fe-occupied cells is maximized or minimized. For these problems we obtain running times of the form O(kn polylog n). We also consider the problem of translating a finite size grid, with m cells, in order to maximize the number of fe-occupied cells. Here we obtain a running time of the form O(knm polylog nm)

    Using participatory design to develop (public) health decision support systems through GIS

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    <p>Abstract</p> <p>Background</p> <p>Organizations that collect substantial data for decision-making purposes are often characterized as being 'data rich' but 'information poor'. Maps and mapping tools can be very useful for research transfer in converting locally collected data into information. Challenges involved in incorporating GIS applications into the decision-making process within the non-profit (public) health sector include a lack of financial resources for software acquisition and training for non-specialists to use such tools. This on-going project has two primary phases. This paper critically reflects on Phase 1: the participatory design (PD) process of developing a collaborative web-based GIS tool.</p> <p>Methods</p> <p>A case study design is being used whereby the case is defined as the data analyst and manager dyad (a two person team) in selected Ontario Early Year Centres (OEYCs). Multiple cases are used to support the reliability of findings. With nine producer/user pair participants, the goal in Phase 1 was to identify barriers to map production, and through the participatory design process, develop a web-based GIS tool suited for data analysts and their managers. This study has been guided by the Ottawa Model of Research Use (OMRU) conceptual framework.</p> <p>Results</p> <p>Due to wide variations in OEYC structures, only some data analysts used mapping software and there was no consistency or standardization in the software being used. Consequently, very little sharing of maps and data occurred among data analysts. Using PD, this project developed a web-based mapping tool (EYEMAP) that was easy to use, protected proprietary data, and permit limited and controlled sharing between participants. By providing data analysts with training on its use, the project also ensured that data analysts would not break cartographic conventions (e.g. using a chloropleth map for count data). Interoperability was built into the web-based solution; that is, EYEMAP can read many different standard mapping file formats (e.g. ESRI, MapInfo, CSV).</p> <p>Discussion</p> <p>Based on the evaluation of Phase 1, the PD process has served both as a facilitator and a barrier. In terms of successes, the PD process identified two key components that are important to users: increased data/map sharing functionality and interoperability. Some of the challenges affected developers and users; both individually and as a collective. From a development perspective, this project experienced difficulties in obtaining personnel skilled in web application development and GIS. For users, some data sharing barriers are beyond what a technological tool can address (e.g. third party data). Lastly, the PD process occurs in real time; both a strength and a limitation. Programmatic changes at the provincial level and staff turnover at the organizational level made it difficult to maintain buy-in as participants changed over time. The impacts of these successes and challenges will be evaluated more concretely at the end of Phase 2.</p> <p>Conclusion</p> <p>PD approaches, by their very nature, encourage buy-in to the development process, better addresses user-needs, and creates a sense of user-investment and ownership.</p

    C–H Borylation Catalysis of Heteroaromatics by a Rhenium Boryl Polyhydride

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    Transition metal complexes bearing metal–boron bonds are of particular relevance to catalytic C–H borylation reactions, with iridium polyboryl and polyhydrido-boryl complexes the current benchmark catalysts for these transformations. Herein, we demonstrate that polyhydride boryl phosphine rhenium complexes are accessible and catalyze the C–H borylation of heteroaromatic substrates. Reaction of [K(DME)(18-c-6)][ReH4(Bpin)(η2-HBpin)(κ2-H2Bpin)] 1 with 1,3-bis(diphenylphosphino)propane (dppp) produced [K(18-c-6)][ReH4(η2-HBpin)(dppp)] 2 through substitution of two equivalents of HBpin, and protonation of 2 formed the neutral complex [ReH6(Bpin)(dppp)] 3. Combined X-ray crystallographic and DFT studies show that 2 is best described as a σ-borane complex, whereas 3 is a boryl complex. Significantly, the boryl complex 3 acted as a catalyst for the C(sp2)–H borylation of a variety of heteroarenes (14 examples including furan, thiophene, pyrrole and indole derivatives) and displayed similar reactivity to the iridium analogues

    Examining the effect of peer helping in a coping skills intervention: a randomized controlled trial for advanced gastrointestinal cancer patients and their family caregivers

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    PURPOSE: At the end of life, spiritual well-being is a central aspect of quality of life for many patients and their family caregivers. A prevalent spiritual value in advanced cancer patients is the need to actively give. To address this need, the current randomized trial examined whether adding a peer helping component to a coping skills intervention leads to improved meaning in life and peace for advanced gastrointestinal cancer patients and their caregivers. Feasibility and acceptability outcomes were also assessed. METHODS: Advanced gastrointestinal cancer patients and caregivers (n = 50 dyads) were randomly assigned to a 5-session, telephone-based coping skills intervention or a peer helping + coping skills intervention. One or both dyad members had moderate-severe distress. Peer helping involved contributing to handouts on coping skills for other families coping with cancer. Patients and caregivers completed measures of meaning in life/peace, fatigue, psychological symptoms, coping self-efficacy, and emotional support. Patient pain and caregiver burden were also assessed. RESULTS: Small effects in favor of the coping skills group were found regarding meaning in life/peace at 1 and 5 weeks post-intervention. Other outcomes did not vary as a function of group assignment, with both groups showing small decreases in patient and caregiver fatigue and caregiver distress and burden. High recruitment and retention rates supported feasibility, and high participant satisfaction ratings supported acceptability. CONCLUSIONS: Although a telephone-based intervention is feasible and acceptable for this population, peer helping in the context of a coping skills intervention does not enhance spiritual well-being relative to coping skills alone

    Creation and Curation of the Society of Imaging Informatics in Medicine Hackathon Dataset

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    In order to support innovation, the Society of Imaging Informatics in Medicine (SIIM) elected to create a collaborative computing experience called a "hackathon." The SIIM Hackathon has always consisted of two components, the event itself and the infrastructure and resources provided to the participants. In 2014, SIIM provided a collection of servers to participants during the annual meeting. After initial server setup, it was clear that clinical and imaging "test" data were also needed in order to create useful applications. We outline the goals, thought process, and execution behind the creation and maintenance of the clinical and imaging data used to create DICOM and FHIR Hackathon resources

    Polar ferromagnet induced by fluorine positioning in isomeric layered copper halide perovskites

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    We acknowledge the University of St Andrews and the China Scholarship Council (studentship to CH) and the University of St Andrews (studentship to AJB).We present the influence of positional isomerism on the crystal structure of fluorobenzylammonium copper (II) chloride perovskites A2CuCl4, by incorporating ortho, meta and para- fluorine substitution in the benzylamine structure. Two-dimensional (2D) polar ferromagnet (3-FbaH)2CuCl4 (3-FbaH+ = 3-fluorobenzylammonium) is successfully obtained, which crystallizes in a polar orthorhombic space group Pca21 at room temperature. In contrast, both (2-FbaH)2CuCl4 (2-FbaH+ = 2-fluorobenzylammonium) and (4-FbaH)2CuCl4 (4-FbaH+ = 4-fluorobenzylammonium) crystallize in centrosymmetric space groups P21/c and Pnma at room temperature, respectively, displaying significant differences in crystal structures. These differences indicate that the position of the fluorine atom is a driver for the polar behaviour in (3-FbaH)2CuCl4. Preliminary magnetic measurements confirm that these three perovskites possess dominant ferromagnetic interactions within the inorganic [CuCl4]∞ layers. Therefore, (3-FbaH)2CuCl4 is a polar ferromagnet, with potential as a type I multiferroic. This work is expected to promote further development of high performance 2D copper (II) halide perovskite multiferroic materials.Publisher PDFPeer reviewe

    Discovery of the Transiting Planet Kepler-5B

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    We present 44 days of high duty cycle, ultra precise photometry of the 13th magnitude star Kepler-5 (KIC 8191672, T(eff) = 6300 K, log g = 4.1), which exhibits periodic transits with a depth of 0.7%. Detailed modeling of the transit is consistent with a planetary companion with an orbital period of 3.548460 +/- 0.000032 days and a radius of 1.431(-0.052)(+0.041) R(J). Follow-up radial velocity measurements with the Keck HIRES spectrograph on nine separate nights demonstrate that the planet is more than twice as massive as Jupiter with a mass of 2.114(-0.059)(+0.056) M(J) and a mean density of 0.894 +/- 0.079 g cm(-3).NASA's Science Mission DirectorateAstronom
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