1,257 research outputs found

    EFFECTS OF SLOW MASS TRANSFER WHEN USING MICROPOROUS ADSORBENTS IN GAS-- SOLID CHROMATOGRAPHY.

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    Diabetes topics associated with engagement on Twitter

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    INTRODUCTION: Social media are widely used by the general public and by public health and health care professionals. Emerging evidence suggests engagement with public health information on social media may influence health behavior. However, the volume of data accumulating daily on Twitter and other social media is a challenge for researchers with limited resources to further examine how social media influence health. To address this challenge, we used crowdsourcing to facilitate the examination of topics associated with engagement with diabetes information on Twitter. METHODS: We took a random sample of 100 tweets that included the hashtag “#diabetes” from each day during a constructed week in May and June 2014. Crowdsourcing through Amazon’s Mechanical Turk platform was used to classify tweets into 9 topic categories and their senders into 3 Twitter user categories. Descriptive statistics and Tweedie regression were used to identify tweet and Twitter user characteristics associated with 2 measures of engagement, “favoriting” and “retweeting.” RESULTS: Classification was reliable for tweet topics and Twitter user type. The most common tweet topics were medical and nonmedical resources for diabetes. Tweets that included information about diabetes-related health problems were positively and significantly associated with engagement. Tweets about diabetes prevalence, nonmedical resources for diabetes, and jokes or sarcasm about diabetes were significantly negatively associated with engagement. CONCLUSION: Crowdsourcing is a reliable, quick, and economical option for classifying tweets. Public health practitioners aiming to engage constituents around diabetes may want to focus on topics positively associated with engagement

    Harvesting graphics power for MD simulations

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    We discuss an implementation of molecular dynamics (MD) simulations on a graphic processing unit (GPU) in the NVIDIA CUDA language. We tested our code on a modern GPU, the NVIDIA GeForce 8800 GTX. Results for two MD algorithms suitable for short-ranged and long-ranged interactions, and a congruential shift random number generator are presented. The performance of the GPU's is compared to their main processor counterpart. We achieve speedups of up to 80, 40 and 150 fold, respectively. With newest generation of GPU's one can run standard MD simulations at 10^7 flops/$.Comment: 12 pages, 5 figures. Submitted to Mol. Si

    Entrepreneurial decision making in a microcosm

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    This study investigates when, how and why students use causation, effectuation and bricolage behaviours within a fundraising project that acted as a microcosm of the entrepreneur’s world. Such a pedagogical device reveals students use of different OM behaviours over the different stages of entrepreneurship. Although research has confirmed the use of these behaviours by entrepreneurs, how student entrepreneurs learn, and practice, them, remains underexplored. Causation is the predominant focus for university teaching, yet our data reveal that students adopted all three behaviours at different stages of the fundraising project as they responded to different contextual forces. Our findings suggest that opportunity management theories should take a more prominent role in the higher education entrepreneurship curriculum. Educators also need to provide a better means of facilitating students to learn about, and practice, a greater repertoire of opportunity management behaviours than is currently the case

    Building better Sex Robots: Lessons from Feminist Pornography

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    How should we react to the development of sexbot technology? Taking their cue from anti-porn feminism, several academic critics lament the development of sexbot technology, arguing that it objectifies and subordinates women, is likely to promote misogynistic attitudes toward sex, and may need to be banned or restricted. In this chapter I argue for an alternative response. Taking my cue from the sex positive ‘feminist porn’ movement, I argue that the best response to the development of ‘bad’ sexbots is to make better ones. This will require changes to the content, process and context of sexbot development. Doing so will acknowledge the valuable role that technology can play in human sexuality, and allow us to challenge gendered norms and assumptions about male and female sexual desire. This will not be a panacea to the social problems that could arise from sexbot development, but it offers a more realistic and hopeful vision for the future of this technology in a pluralistic and progressive society

    Longitudinal-Transverse Separations of Structure Functions at Low Q2Q^{2} for Hydrogen and Deuterium

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    We report on a study of the longitudinal to transverse cross section ratio, R=σL/σTR=\sigma_L/\sigma_T, at low values of xx and Q2Q^{2}, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Lab Hall C spanning the four-momentum transfer range 0.06 <Q2<2.8 < Q^{2} < 2.8 GeV2^{2}. Even at the lowest values of Q2Q^{2}, RR remains nearly constant and does not disappear with decreasing Q2Q^{2}, as expected. We find a nearly identical behaviour for hydrogen and deuterium.Comment: 4 pages, 2 gigure

    HIGH-PRECISION GAS CHROMATOGRAPHY.

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    Relating geologic units and mobility system kinematics contributing to Curiosity wheel damage at Gale Crater, Mars

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    Curiosity landed on plains to the north of Mount Sharp in August 2012. By June 2016 the rover had traversed 12.9 km to the southwest, encountering extensive strata that were deposited in a fluvial-deltaic-lacustrine system. Initial drives across sharp sandstone outcrops initiated an unacceptably high rate of punctures and cracks in the thin aluminum wheel skin structures. Initial damage was found to be related to the drive control mode of the six wheel drive actuators and the kinematics of the rocker-bogie suspension. Wheels leading a suspension pivot were forced onto sharp, immobile surfaces by the other wheels as they maintained their commanded angular velocities. Wheel damage mechanisms such as geometry-induced stress concentration cracking and low-cycle fatigue were then exacerbated. A geomorphic map was generated to assist in planning traverses that would minimize further wheel damage. A steady increase in punctures and cracks between landing and June 2016 was due in part because of drives across the sharp sandstone outcrops that could not be avoided. Wheel lifetime estimates show that with careful path planning the wheels will be operational for an additional ten kilometers or more, allowing the rover to reach key strata exposed on the slopes of Mount Sharp
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