102 research outputs found

    A five-stage treatment train for water recovery from urine and shower water for long-term human Space missions

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    Long-term human Space missions will rely on regenerative life support as resupply of water, oxygen and food comes with constraints. The International Space Station (ISS) relies on an evaporation/condensation system to recover 74-85% of the water in urine, yet suffers from repetitive scaling and biofouling while employing hazardous chemicals. In this study, an alternative non-sanitary five-stage treatment train for one "astronaut" was integrated through a sophisticated monitoring and control system. This so-called Water Treatment Unit Breadboard (WTUB) successfully treated urine (1.2-L-d with crystallisation, COD-removal, ammonification, nitrification and electrodialysis, before it was mixed with shower water (3.4-L-d(-1)). Subsequently, ceramic nanofiltration and single-pass flat-sheet RO were used. A four-months proof-of-concept period yielded: (i) chemical water quality meeting the hygienic standards of the European Space Agency, (ii) a 87- +/- -5% permeate recovery with an estimated theoretical primary energy requirement of 0.2-kWh p -L-1, (iii) reduced scaling potential without anti-scalant addition and (iv) and a significant biological reduction in biofouling potential resulted in stable but biofouling-limited RO permeability of 0.5 L-m(-2)-h(-1)-bar(-1). Estimated mass breakeven dates and a comparison with the ISS Water Recovery System for a hypothetical Mars transit mission show that WTUB is a promising biological membrane-based alternative to heat-based systems for manned Space missions

    Comparison of plasma endothelin levels between osteoporotic, osteopenic and normal subjects

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    BACKGROUND: It has been demonstrated that endothelins (ET) have significant roles in bone remodeling, metabolism and physiopathology of several bone diseases. We aimed to investigate if there was any difference between the plasma ET levels of osteoporotic patients and normals. METHODS: 86 patients (70 women and 16 men) with a mean age of 62.6 (ranges: 51–90) years were included in this study. Patients were divided into groups of osteoporosis, osteopenia and normal regarding reported T scores of DEXA evaluation according to the suggestions of World Health Organization. According to these criteria 19, 43 and 24 were normal, osteopenic and osteoporotic respectively. Then total plasma level of ET was measured in all patients with monoclonal antibody based sandwich immunoassay (EIA) method. One-way analysis of variance test was used to compare endothelin values between normals, osteopenics and osteoporotics. RESULTS: Endothelin total plasma level in patients was a mean of 98.36 ± 63.96, 100.92 ± 47.2 and 99.56 ± 56.6 pg/ml in osteoporotic, osteopenic and normal groups respectively. The difference between groups was not significant (p > 0.05). CONCLUSION: No significant differences in plasma ET levels among three groups of study participants could be detected in this study

    Co-production: towards a utopian approach

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    This article outlines how co-production might be understood as a utopian method, which both attends to and works against dominant inequalities. It suggests that it might be positioned ‘within, against, and beyond’ current configurations of power in academia and society more broadly. It develops this argument by drawing on recent research funded through the UK’s Connected Communities programme, led by the Arts and Humanities Research Council; and by attending to arguments from the field of Utopian Studies. It explores particular issues of power and control within the field of co-production, acknowledging that neoliberalism both constrains and co-opts such practice; and explores methodological and infrastructural issues such that its utopian potential might be realised

    Water Treatment Unit Breadboard : ground test facility for the recycling of urine and shower water for one astronaut

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    One of the major challenges for long-term manned Space missions is the requirement of a regenerative life support system. When minimizing the amount of water available per astronaut to 13 L d-1, a mission of 6 crew members requires almost 30 ton of fresh water supplies per year, i.e. the International Space Station (ISS) weighs approximately 400 ton. Therefore, the development of an efficient water recovery system is essential to future Space exploration. A Water Treatment Unit Breadboard (WTUB) has been developed to recover 90% of the water in urine, condensate and shower water produced by one crew member and this life support testbed facility was inspired by the MELiSSA loop concept, ESA's Life Support System. In the WTUB, a water recovery of >85% was achieved by an integrated bio-physicochemical urine treatment combined with NF/RO filtration
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