322 research outputs found
Electrochemical Solutions for Advanced Life Support
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
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
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
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De novo assembly of the cattle reference genome with single-molecule sequencing.
BackgroundMajor advances in selection progress for cattle have been made following the introduction of genomic tools over the past 10-12 years. These tools depend upon the Bos taurus reference genome (UMD3.1.1), which was created using now-outdated technologies and is hindered by a variety of deficiencies and inaccuracies.ResultsWe present the new reference genome for cattle, ARS-UCD1.2, based on the same animal as the original to facilitate transfer and interpretation of results obtained from the earlier version, but applying a combination of modern technologies in a de novo assembly to increase continuity, accuracy, and completeness. The assembly includes 2.7 Gb and is >250Ă more continuous than the original assembly, with contig N50 >25 Mb and L50 of 32. We also greatly expanded supporting RNA-based data for annotation that identifies 30,396 total genes (21,039 protein coding). The new reference assembly is accessible in annotated form for public use.ConclusionsWe demonstrate that improved continuity of assembled sequence warrants the adoption of ARS-UCD1.2 as the new cattle reference genome and that increased assembly accuracy will benefit future research on this species
Prenatal Vitamin D Supplementation and Child Respiratory Health: A Randomised Controlled Trial
PMCID: PMC3691177This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Coronary CT Angiography and 5-Year Risk of Myocardial Infarction.
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
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
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 participantsâ 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 participantsâ 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 patientsâ 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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