4,710 research outputs found

    Regular expressions as violin bowing patterns

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    String players spend a significant amount of practice time creating and learning bowings. These may be indicated in the music using up-bow and down-bow symbols, but those traditional notations do not capture the complex bowing patterns that are latent within the music. Regular expressions, a mathematical notation for a simple class of formal languages, can describe precisely the bowing patterns that commonly arise in string music. A software tool based on regular expressions enables performers to search for passages that can be handled with similar bowings, and to edit them consistently. A computer-based music editor incorporating bowing patterns has been implemented, using Lilypond to typeset the music. Our approach has been evaluated by using the editor to study ten movements from six violin sonatas by W. A. Mozart. Our experience shows that the editor is successful at finding passages and inserting bowings; that relatively complex patterns occur a number of times; and that the bowings can be inserted automatically and consistently

    Biomechanical mechanisms underlying exosuit-induced improvements in walking economy after stroke

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    Stroke-induced hemiparetic gait is characteristically asymmetric and metabolically expensive. Weakness and impaired control of the paretic ankle contribute to reduced forward propulsion and ground clearance—walking subtasks critical for safe and efficient locomotion. Targeted gait interventions that improve paretic ankle function after stroke are therefore warranted. We have developed textile-based, soft wearable robots that transmit mechanical power generated by off-board or body-worn actuators to the paretic ankle using Bowden cables (soft exosuits) and have demonstrated the exosuits can overcome deficits in paretic limb forward propulsion and ground clearance, ultimately reducing the metabolic cost of hemiparetic walking. This study elucidates the biomechanical mechanisms underlying exosuit-induced reductions in metabolic power. We evaluated the relationships between exosuit-induced changes in the body center of mass (COM) power generated by each limb, individual joint powers, and metabolic power. Compared to walking with an exosuit unpowered, exosuit assistance produced more symmetrical COM power generation during the critical period of the step-to-step transition (22.4±6.4% more symmetric). Changes in individual limb COM power were related to changes in paretic (R2= 0.83, P= 0.004) and nonparetic (R2= 0.73, P= 0.014) ankle power. Interestingly, despite the exosuit providing direct assistance to only the paretic limb, changes in metabolic power were related to changes in nonparetic limb COM power (R2= 0.80, P= 0.007), not paretic limb COM power (P> 0.05). These findings provide a fundamental understanding of how individuals poststroke interact with an exosuit to reduce the metabolic cost of hemiparetic walking.Accepted manuscript2019-03-0

    Development of the South Canterbury / Otago southern bluefin tuna fishery

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    There is concern that many of New Zealand's inshore fish species are being overfished to the extent that fishing effort will have to be reduced to ensure the continued existence of some species as commercial stocks. A dual solution of both reducing the total level of fishing effort and transferring fishing effort to alternative fisheries to alleviate the problem is possible. This report examines the economics of transferring fishing effort to southern bluefin tuna capture off the South Canterbury / Otago coast, and is therefore an example of the problems and potential in transferring fishing effort. The study pays particular attention to the extension needs in developing fisheries using the results of a census of skippers in the region. Two chapters have been included to give the reader some background to the southern bluefin tuna fishery and the South Canterbury/Otago fishery. From this information the potential benefits of development, the direct cost of catching bluefin and the opportunity cost of foregoing catching traditional species have been estimated. The indirect costs of providing the necessary infrastructure for development were estimated from the survey. The survey also provided information on the readiness of fishermen and their vessels to undertake southern bluefin tuna fishing. This paper does not consider the effect on the traditional fish stocks of transferring catching effort to alternative fisheries. However, consideration is given to the economics of transferring catching effort to alternative fisheries regardless of the reasons for having an effort reduction scheme. The cost benefit analysis has seven scenarios based on the extent to which developing the bluefin fishing is able to alleviate the present inshore fisheries management problems

    Fractional flow reserve vs. angiography in guiding management to optimize outcomes in non-ST-segment elevation myocardial infarction: the British Heart Foundation FAMOUS-NSTEMI randomized trial

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    Aim: We assessed the management and outcomes of non-ST segment elevation myocardial infarction (NSTEMI) patients randomly assigned to fractional flow reserve (FFR)-guided management or angiography-guided standard care. Methods and results: We conducted a prospective, multicentre, parallel group, 1 : 1 randomized, controlled trial in 350 NSTEMI patients with ≥ coronary stenosis ≥30% of the lumen diameter assessed visually (threshold for FFR measurement) (NCT01764334). Enrolment took place in six UK hospitals from October 2011 to May 2013. Fractional flow reserve was disclosed to the operator in the FFR-guided group (n = 176). Fractional flow reserve was measured but not disclosed in the angiography-guided group (n = 174). Fractional flow reserve ≤0.80 was an indication for revascularization by percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). The median (IQR) time from the index episode of myocardial ischaemia to angiography was 3 (2, 5) days. For the primary outcome, the proportion of patients treated initially by medical therapy was higher in the FFR-guided group than in the angiography-guided group [40 (22.7%) vs. 23 (13.2%), difference 95% (95% CI: 1.4%, 17.7%), P = 0.022]. Fractional flow reserve disclosure resulted in a change in treatment between medical therapy, PCI or CABG in 38 (21.6%) patients. At 12 months, revascularization remained lower in the FFR-guided group [79.0 vs. 86.8%, difference 7.8% (−0.2%, 15.8%), P = 0.054]. There were no statistically significant differences in health outcomes and quality of life between the groups. Conclusion: In NSTEMI patients, angiography-guided management was associated with higher rates of coronary revascularization compared with FFR-guided management. A larger trial is necessary to assess health outcomes and cost-effectiveness

    The effects of room design on computer-supported collaborative learning in a multi-touch classroom.

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    While research indicates that technology can be useful for supporting learning and collaboration, there is still relatively little uptake or widespread implementation of these technologies in classrooms. In this paper, we explore one aspect of the development of a multi-touch classroom, looking at two different designs of the classroom environment to explore how classroom layout may influence group interaction and learning. Three classes of students working in groups of four were taught in the traditional forward-facing room condition, while three classes worked in a centered room condition. Our results indicate that while the outcomes on tasks were similar across conditions, groups engaged in more talk (but not more off-task talk) in a centered room layout, than in a traditional forward-facing room. These results suggest that the use of technology in the classroom may be influenced by the location of the technology, both in terms of the learning outcomes and the interaction behaviors of students. The findings highlight the importance of considering the learning environment when designing technology to support learning, and ensuring that integration of technology into formal learning environments is done with attention to how the technology may disrupt, or contribute to, the classroom interaction practices
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