322 research outputs found

    Electrochemical Solutions for Advanced Life Support

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    The Oxygen Generating Assembly (OGA) on-board the International Space Station (ISS) employs a polymer electrolyte membrane (PEM) water electrolysis cell stack to electrochemically dissociate water into its two components oxygen and hydrogen. Oxygen is provided to the cabin atmosphere for crew respiration while the hydrogen is delivered to a carbon dioxide reduction system to recover oxygen as water. The design of the OGA evolved over a number of years to arrive at the system solution that is currently operational on ISS. Future manned missions to space will require advanced technologies that eliminate the need for resupply from earth and feature in-situ resource utilization to sustain crew life and to provide useful materials to the crew. The architects planning such missions should consider all potential solutions at their disposal to arrive at an optimal vehicle solution that minimizes crew maintenance time, launch weight, installed volume and energy consumption demands. Skyre is developing new technologies through funding from NASA, the Department of Energy, and internal investment based on PEM technology that could become an integral part of these new vehicle solutions. At varying stages of Technology Readiness Level (TRL) are: an oxygen concentrator and compressor that can separate oxygen from an air stream and provide an enriched oxygen resource for crew medical use and space suit recharge without any moving parts in the pure oxygen stream; a regenerative carbon dioxide removal system featuring a PEM-based sorbent regenerator; a carbon dioxide reduction system that electrochemically produces organic compounds that could serve as fuels or as a useful intermediary to more beneficial compounds; and an electrochemical hydrogen separator and compressor for hydrogen recycle. The technical maturity of these projects is presented along with pertinent performance test data that could be beneficial in future study efforts

    Nonlinear optics of fibre event horizons

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    The nonlinear interaction of light in an optical fibre can mimic the physics at an event horizon. This analogue arises when a weak probe wave is unable to pass through an intense soliton, despite propagating at a different velocity. To date, these dynamics have been described in the time domain in terms of a soliton-induced refractive index barrier that modifies the velocity of the probe. Here, we complete the physical description of fibre-optic event horizons by presenting a full frequency-domain description in terms of cascaded four-wave mixing between discrete single-frequency fields, and experimentally demonstrate signature frequency shifts using continuous wave lasers. Our description is confirmed by the remarkable agreement with experiments performed in the continuum limit, reached using ultrafast lasers. We anticipate that clarifying the description of fibre event horizons will significantly impact on the description of horizon dynamics and soliton interactions in photonics and other systems.Comment: 7 pages, 5 figure

    Morally Respectful Listening and its Epistemic Consequences

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    What does it mean to listen to someone respectfully, that is, insofar as they are due recognition respect? This paper addresses that question and gives the following answer: it is to listen in such a way that you are open to being surprised. A specific interpretation of this openness to surprise is then defended

    Coronary CT Angiography and 5-Year Risk of Myocardial Infarction.

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    BACKGROUND: Although coronary computed tomographic angiography (CTA) improves diagnostic certainty in the assessment of patients with stable chest pain, its effect on 5-year clinical outcomes is unknown. METHODS: In an open-label, multicenter, parallel-group trial, we randomly assigned 4146 patients with stable chest pain who had been referred to a cardiology clinic for evaluation to standard care plus CTA (2073 patients) or to standard care alone (2073 patients). Investigations, treatments, and clinical outcomes were assessed over 3 to 7 years of follow-up. The primary end point was death from coronary heart disease or nonfatal myocardial infarction at 5 years. RESULTS: The median duration of follow-up was 4.8 years, which yielded 20,254 patient-years of follow-up. The 5-year rate of the primary end point was lower in the CTA group than in the standard-care group (2.3% [48 patients] vs. 3.9% [81 patients]; hazard ratio, 0.59; 95% confidence interval [CI], 0.41 to 0.84; P=0.004). Although the rates of invasive coronary angiography and coronary revascularization were higher in the CTA group than in the standard-care group in the first few months of follow-up, overall rates were similar at 5 years: invasive coronary angiography was performed in 491 patients in the CTA group and in 502 patients in the standard-care group (hazard ratio, 1.00; 95% CI, 0.88 to 1.13), and coronary revascularization was performed in 279 patients in the CTA group and in 267 in the standard-care group (hazard ratio, 1.07; 95% CI, 0.91 to 1.27). However, more preventive therapies were initiated in patients in the CTA group (odds ratio, 1.40; 95% CI, 1.19 to 1.65), as were more antianginal therapies (odds ratio, 1.27; 95% CI, 1.05 to 1.54). There were no significant between-group differences in the rates of cardiovascular or noncardiovascular deaths or deaths from any cause. CONCLUSIONS: In this trial, the use of CTA in addition to standard care in patients with stable chest pain resulted in a significantly lower rate of death from coronary heart disease or nonfatal myocardial infarction at 5 years than standard care alone, without resulting in a significantly higher rate of coronary angiography or coronary revascularization. (Funded by the Scottish Government Chief Scientist Office and others; SCOT-HEART ClinicalTrials.gov number, NCT01149590 .)

    Blueberry Advisory Committee Research Report

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    The 1985 edition of the Blueberry Progress Reports was prepared for the Maine Blueberry Commission and the University of Maine Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include: 1. Control of secondary blueberry pest insects 2. Effect of pruning practices on blueberry insect abundance 3. Effect of hexazinone on species distribution in lowbush blueberry fields 4. Dichlobenil for control of bunchberry 5. Evaluation of postemergence herbicides for grass control 6. Hand-wiper applications of herbicides on woody weeds 7. Evaluation of steam as a pruning practice for lowbush blueberry fields 8. Evaluation of glyphosate and 2,4-D applied with a commercial weed roller to control woody weeds 9. Hand-wiping and cutting treatments for dogbane 9. Evaluation of airblast-sprayer application of asulam for bracken fern control 10. Spot treatment of woody weeds with 2,4-D in oil 11. Chemical control of Botrytis blossom blight 12. Evaluation of preliminary steam treatments (1984) at Blueberry Hill Farm 13. Long term effects of N and NPK fertilizer on plant growth and yield 14. Nutritional survey of selected lowbush blueberry fields 15. Interaction of fertility and pruning practices on soil characteristics and lowbush blueberry growth and yield 16. Frequency of fertility application for establishment of lowbush blueberry seedlings 17. Slow release vs. liquid fertilizer for establishment of lowbush blueberry seedlings 18. The effect of several mulches on frost heaving, soil moisture, soil temperature and rhizome development 19. Blueberry product development: raisin-type blueberries 20. Blueberry product development: blueberry puree 21. Addendum: 1985 Report from Moody Trevet

    Using a picture-based book to support epilepsy care in clinical consultations for people with intellectual disabilities

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    Background and aims People with intellectual disabilities are more likely to have epilepsy than the general population. A picture-based book, Getting on with Epilepsy, may help to improve their epilepsy management and quality of life. The present study aimed to explore how the book could be best used in routine clinical care. Methods Twenty people with epilepsy and intellectual disabilities were video-recorded using the Getting on with Epilepsy book with a nurse or doctor. This was analysed using conversation analytic methods. Eighteen patients and five clinicians took part in interviews to explore their views on book use, which were thematically analysed. All data were then synthesised to form themes. Results Three themes were identified which demonstrated the importance of (1) understanding the book depicted seizures (2) relating the book to the participants’ experiences (3) using the book as an education and information tool. The themes highlighted the techniques and approaches that clinicians used to facilitate understanding. Some tensions and differences were noted between training and implementation in routine practice, particularly around prompts in themes 1 and 3 intended to correct or change participants’ interpretation of the book. Conclusions The Getting on with Epilepsy book can be used in routine clinical practice to support people with intellectual disabilities and epilepsy. There was a balance between exploring patients’ narratives and understanding with the need to convey clinical information, and this may also apply to the use of other accessible resources
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