Medium-term performance and maintenance of SUDS:a case-study of Hopwood Park Motorway Service Area, UK

One of the main barriers to implementing SUDS is concern about performance and maintenance costs since there are few well-documented case-studies. This paper summarizes studies conducted between 2000 and 2008 of the performance and maintenance of four SUDS management trains constructed in 1999 at the Hopwood Park Motorway Service Area, central England. Assessments were made of the wildlife value and sedimentation in the SUDS ponds, the hydraulic performance of the coach park management train, water quality in all management trains, and soil/sediment composition in the grass filter strip, interceptor and ponds. Maintenance procedures and costs were also reviewed. Results demonstrate the benefits of a management train approach over individual SUDS units for flow attenuation, water treatment, spillage containment and maintenance. Peak flows, pond sediment depth and contaminant concentrations in sediment and water decreased through the coach park management train. Of the 2007 annual landscape budget of £15,000 for the whole site, the maintenance costs for SUDS only accounted for £2,500 compared to £4,000 for conventional drainage structures. Furthermore, since sediment has been attenuated in the management trains, the cost of sediment removal after the recommended period of three years was only £554 and, if the design is not compromised, less frequent removal will be required in future

Evaluation of the pathways of tropospheric nitrophenol formation using a multiphase model

International audiencePhenols are a major class of volatile organic compounds (VOC) whose reaction within, and partitioning between, the gas and liquid phases affects their lifetime within the atmosphere, the local oxidising capacity, and the extent of production of nitrophenols, which are toxic chemicals. In this work, a zero-dimension box model was constructed to quantify the relative nitration pathways, and partitioning into the liquid phase, of mono-aromatic compounds in order to help elucidate the formation pathways of 2- and 4-nitrophenol in the troposphere. The liquid phase contributed significantly to the production of nitrophenols for liquid water content (Lc) values exceeding 3×10-9, and for a range of assumed liquid droplet diameter, even though the resultant equilibrium partitioning to the liquid phase was much lower. For example, in a ''typical'' model scenario, with Lc=3×10-7, 58% of nitrophenol production occurred in the liquid phase but only 2% of nitrophenol remained there, i.e. a significant proportion of nitrophenol observed in the gas phase may actually be produced via the liquid phase. The importance of the liquid phase was enhanced at lower temperatures, by a factor ~1.5?2 at 278 K cf. 298 K. The model showed that nitrophenol production was particularly sensitive to the values of the rate coefficients for the liquid phase reactions between phenol and OH or NO3 reactions, but insensitive to the rate coefficient for the reaction between benzene and OH, thus identifying where further experimental data are required

Believing in Multiple Equilibria

If agents have common priors concerning the probability with which equilibrium is selected, they have an incentive to trade beforehand. If their trading process satisfies a certain notion of individual rationality, these trades will reduce and ultimately remove all uncertainty concerning equilibrium selection. In this sense, multiple equilibria engender institutions which can uniquely determine equilibrium

The effects of arthritis gloves on hand pain in people with rheumatoid or inflammatory arthritis : a randomised controlled trial (A-GLOVES TRIAL)

Background: Arthritis (compression) gloves are commonly provided to people with rheumatoid arthritis (RA) and undifferentiated inflammatory arthritis (IA) in the UK health service. These apply pressure and warmth to relieve hand pain, stiffness and improve hand function. A systematic review identified little evidence to support their use.[1] Objectives: This randomised controlled trial tested effectiveness and cost-effectiveness of mid-finger length compression (intervention) gloves (20% Lycra: commonest glove model provided) with control gloves (i.e. oedema gloves: 11% Lycra: fitted at least one size too big) in people with RA and IA. Methods: Both gloves, which had similar thermal qualities although the control gloves did not provide compression, were provided by rheumatology occupational therapists, following training.[2] Participants were also given brief advice on hand exercise and joint protection. Adults with RA/IA and persistent hand pain were randomised 1:1 to the two glove types, stratified by disease modifying anti-rheumatic drug (DMARD) change in previous 12 weeks. The primary outcome was dominant hand pain on activity Visual Analogue Scale (VAS:0–10); other outcomes included night hand pain, hand stiffness (both 0–10 VAS); Measure of Activity Performance Hand (MAP-HAND: 0–3). Multiple linear regression was undertaken to estimate the effect of group allocation on hand pain during activity, adjusting for the stratification variable and baseline values. Cost-effectiveness used individual patient level costs (intervention plus healthcare utilisation) and health benefit data (EQ-5D) to calculate costs and QALYs. Results: 206 participants were randomised (103 to each glove type): median age 59 years [IQR 51,67]; women:166 (81%); mean disease duration: 8.2 (SD 9.5) years; employed:76 (37%); right hand dominant:185 (90%). Of these, 163 (79%) completed 12 week follow-up questionnaires. Both groups reported similar adherence to glove wear (mean 5.2 days/week). At 12 w, hand pain scores in both groups similarly improved: the between-groups mean difference of 0.1 was not statistically significant (95% CI: −0.47 to 0.67; p=0.72). There were no significant differences between groups on any measures, with both groups improving similarly between baseline and 12 w. 73% in both groups considered gloves beneficial. Intervention gloves had higher costs (£552 (SD £464); control £391 (SD £543) but comparable benefits to control gloves. Intervention gloves would cost £83 700 to gain one QALY and were not likely to be cost-effective. Conclusions: Compression (intervention) and loose-fitting arthritis (control) gloves had similar effects on hand pain, stiffness and function. Therefore, compression is not the ‘active ingredient’ in arthritis gloves. Loose fitting gloves providing warmth were perceived as equally effective by participants. We do not know if the therapist effect is important or whether ordinary gloves providing warmth would provide similar results. References: Hammond, et al. Clin Rehabil 2016 30:213–24. Prior, et al. Rheumatology 2017. www.abstractsonline.com/pp8/#!/4205 Acknowledgements: This project was funded by the NIHR Research for Patient Benefit Programme (PB-PG-0214–33010). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health

Rigidity analysis of HIV-1 protease

We present a rigidity analysis on a large number of X-ray crystal structures of the enzyme HIV-1 protease using the 'pebble game' algorithm of the software FIRST. We find that although the rigidity profile remains similar across a comprehensive set of high resolution structures, the profile changes significantly in the presence of an inhibitor. Our study shows that the action of the inhibitors is to restrict the flexibility of the beta-hairpin flaps which allow access to the active site. The results are discussed in the context of full molecular dynamics simulations as well as data from NMR experiments.Comment: 4 pages, 3 figures. Conference proceedings for CMMP conference 2010 which was held at the University of Warwic

The Integrability of Pauli System in Lorentz Violating Background

We systematically analyze the integrability of a Pauli system in Lorentz violating background at the non-relativistic level both in two- and three-dimensions. We consider the non-relativistic limit of the Dirac equation from the QED sector of the so-called Standard Model Extension by keeping only two types of background couplings, the vector a_mu and the axial vector b_mu. We show that the spin-orbit interaction comes as a higher order correction in the non-relativistic limit of the Dirac equation. Such an interaction allows the inclusion of spin degree non-trivially, and if Lorentz violating terms are allowed, they might be comparable under special circumstances. By including all possible first-order derivative terms and considering the cases a\ne 0, b\ne 0, and b_0\ne 0 one at a time, we determine the possible forms of constants of motion operator, and discuss the existence or continuity of integrability due to Lorentz violating background.Comment: 19 page

Analysis of clogging in constructed wetlands using magnetic resonance

In this work we demonstrate the potential of permanent magnet based magnetic resonance sensors to monitor and assess the extent of pore clogging in water filtration systems. The performance of the sensor was tested on artificially clogged gravel substrates and on gravel bed samples from constructed wetlands used to treat wastewater. Data indicate that the spin lattice relaxation time is linearly related to the hydraulic conductivity in such systems. In addition, within biologically active filters we demonstrate the ability to determine the relative ratio of biomass to abiotic solids, a measurement which is not possible using alternative techniques