1,224 research outputs found
Terrestrial organic carbon storage in a British moorland
Accurate estimates for the size of terrestrial organic carbon (C) stores are needed to determine their importance in regulating atmospheric CO2 concentrations. The C stored in vegetation and soil components of a British moorland was evaluated in order to: (i) investigate the importance of these ecosystems for C storage and (ii) test the accuracy of the United Kingdom's terrestrial C inventory. The area of vegetation and soil types was determined using existing digitized maps and a Geographical Information System (GIS). The importance of evaluating C storage using 2D area projections, as opposed to true surface areas, was investigated and found to be largely insignificant. Vegetation C storage was estimated from published results of productivity studies at the site supplemented by field sampling to evaluate soil C storage. Vegetation was found to be much less important for C storage than soil, with peat soils, particularly Blanket bog, containing the greatest amounts of C. Whilst the total amount of C in vegetation was similar to the UK national C inventory's estimate for the same area, the national inventory estimate for soil C was over three times higher than the value derived in the current study. Because the UK's C inventory can be considered relatively accurate compared to many others, the results imply that current estimates for soil C storage, at national and global scales, should be treated with caution
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
Systematic biases in measurement of urban nitrogen dioxide using passive diffusion samplers
Measurement of nitrogen dioxide using passive diffusion tube over 22 months in Cambridge,
U.K. are analysed as a function of sampler exposure time, and compared with NO2 concentrations
obtained from a co-located chemiluminescence analyser. The average ratios of passive sampler
to analyser NO2 at a city centre site (mean NO2 concentration 22 ppb) are 1.27 (n = 22), 1.16 (n
= 34) and 1.11 (n = 7) for exposures of 1, 2 and 4-weeks, respectively. Modelling the generation
of extra NO2 arising from chemical reaction between co-diffusing NO and O3 in the tube gave a
ratio (modelled/measured) of 1.31 for 1-week exposures. Such overestimation is greatest when NO2
constitutes, on average, about half of total NOx (= NO + NO2) at the monitoring locality. Although 4-
week exposures gave concentrations which were not significantly different from analyser NO2, there
was no correlation between the datasets. At both the city-centre site and another semi-rural site (mean
NO2 concentration 11 ppb) the average of the aggregate of four consecutive 1-week sampler exposures
or of two consecutive 2-week sampler exposures was systematically greater than for a single
4-week exposure. The results indicate two independent and opposing systematic biases in measurement
of NO2 by passive diffusion sampler: an exposure-time independent chemical overestimation
with magnitude determined by local relative concentrations of NO and O3 to NO2, and an exposuretime
dependent reduction in sampling efficiency. The impact of these and other potential sources of
systematic bias on the application of passive diffusion tubes for assessing ambient concentrations of
NO2 in short (1-week) or long (4-week) exposures are discussed in detail
Evaluation of Complex Whole-School Interventions: Methodological and Practical Considerations
Evaluating the impact of complex whole-school interventions (CWSIs) is challenging.
However, what evidence there is suggests that school leadership and other elements of
whole-school contexts are important for pupils’ attainment (Leithwood et al., 2006),
suggesting that interventions aimed at changing these have significant potential to
improve pupil outcomes. Furthermore, strong leadership is likely important for the effective
implementation of many interventions funded by the EEF since even class-level or
targeted programmes are more likely to work best within supportive and effective settings.
We therefore welcome the EEF’s commitment to exploring the issues inherent in
evaluating CWSIs. Developing design and practice for evaluations of this type of
intervention, focusing on the issues of complexity and managing change across a whole
school, increases the scope of projects of which the EEF may confidently fund evaluations.
In this document, we provide key messages for EEF evaluators on how to get the most out
of evaluations of CWSIs, including considerations for both design and implementation. As
far as possible, our suggestions aim to be practical steps that evaluators can implement
immediately. A number of issues, and points 13 and 14 below in particular, require either
further investigation or decisions from the EEF
Improving the visibility of hydrological sciences from developing countries
The increasing level of competition in scientific publishing arguably has a greater negative impact on hydrologists from developing countries and specifically young scientists. This paper discusses the constraints they face and offers suggestions to authors and the hydrological community about how these may be mitigated. These include a lack of access to resources to assist with creating good publications, the difficulty of publishing research based on relatively scarce data, a common problem in many developing countries, and a lack of familiarity with the process of publishing scientific material together with limited access to mentorship from experienced authors. A key point is to ensure that the research question addressed has a broad interest beyond the local study area. However, the more limited hydrological knowledge and the water resources problems of developing countries represent opportunities for internationally relevant research, particularly within the nexus between hydrology and society, or between science and practice. Both of these are high on the international hydrological research agenda
Chapter 17 - Economics of adaptation
This chapter assesses the literature on the economics of climate change adaptation, building on the Fourth Assessment Report (AR4) and the increasing role that economic considerations are playing in adaptation decisionmaking and policy. AR4 provided a limited assessment of the costs and benefits of adaptation, based on narrow and fragmented sectoral and regional literature (Adger et al, 2007). Substantial advances have been made in the economics of climate change adaptation after AR4
The influence of weather-type and long-range transport on airborne particle concentrations in Edinburgh, UK
This study investigated the influence of regional-scale synoptic weather type and
geographical source regions of air masses on two-particle concentration metrics
(Black Smoke (BS) and PM10) in the city of Edinburgh, UK, between 1981 and 1996.
Twenty-seven classifications of Jenkinson Daily Weather Types (JWT) were subdivided
into 9 directional categories and 3 vorticity categories, and the influence of
JWT category on BS and PM10 determined. Four-day air mass back-trajectories for 1
July 1995–30 June 1996 were computed and grouped into 8 categories depending on
the geographical route followed. Significantly elevated concentrations of BS (median
values 2, 5 and 4 μg m−3 greater than median for 1981–1996) and PM10 (median
values 3, 5.5 and 8 μg m−3 greater than median for 1992–1996) were observed for
anticyclonic, southerly and south-easterly weather types, respectively. These
differences were not identified at conventional levels of significance for BS in 1995–
1996. This may reflect a shift in more recent times to lower concentrations of
predominantly locally emitted BS less affected by regional scale meteorology.
Conversely, significant inter-trajectory category differences were observed for PM10
during 1995–1996, with highest concentrations associated with Eastern European
trajectories and south-easterly weather type categories (11.4 and 10.7 μg m−3 greater
than annual means, respectively). The variation in particle concentration across
weather-type was a significant proportion of total median particle concentration, and
of a magnitude associated with adverse health outcomes. Thus current PM10
concentrations (and associated health outcomes) in Edinburgh are likely to be
significantly influenced by regional-scale meteorology independent of local air quality
management areas. Furthermore, changes in long-term trends in distributions of
synoptic weather types indicate that future climate change may influence exposure to
PM10 and the PM10:BS ratio in Edinburgh. Further definition of the relationships
between long-range transport and particle concentration will improve classification of
human exposure in epidemiological studies
Illusory perceptions of space and time preserve cross-saccadic perceptual continuity
When voluntary saccadic eye movements are made to a silently ticking clock, observers sometimes think that the second hand takes longer than normal to move to its next position. For a short period, the clock appears to have stopped (chronostasis). Here we show that the illusion occurs because the brain extends the percept of the saccadic target backwards in time to just before the onset of the saccade. This occurs every time we move the eyes but it is only perceived when an external time reference alerts us to the phenomenon. The illusion does not seem to depend on the shift of spatial attention that accompanies the saccade. However, if the target is moved unpredictably during the saccade, breaking perception of the target's spatial continuity, then the illusion disappears. We suggest that temporal extension of the target's percept is one of the mechanisms that 'fill in' the perceptual 'gap' during saccadic suppression. The effect is critically linked to perceptual mechanisms that identify a target's spatial stability
Myocardial infarction, ST-elevation and non-ST-elevation myocardial infarction and modelled daily pollution concentrations; a case-crossover analysis of MINAP data
Objectives: To investigate associations between daily concentrations of air pollution and myocardial infarction (MI), ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI).
Methods: Modelled daily ground-level gaseous, total and speciated particulate pollutant concentrations and ground-level daily mean temperature, all at 5 km x 5 km horizontal resolution, were linked to 202,550 STEMI and 322,198 NSTEMI events recorded on the England and Wales Myocardial Ischaemia National Audit Project (MINAP) database. The study period was 2003-2010. A case-crossover design was used, stratified by year, month, and day of the week. Data were analysed using conditional logistic regression, with pollutants modelled as unconstrained distributed lags 0-2 days. Results are presented as percentage change in risk per 10 µg/m3 increase in the pollutant relevant metric, having adjusted for daily mean temperature, public holidays, weekly flu consultation rates, and a sine-cosine annual cycle.
Results: There was no evidence of an association between MI or STEMI and any of O3, NO2, PM2.5, PM10 or selected PM2.5 components (sulphate and elemental carbon). For NSTEMI there was a positive association with daily maximum 1-hour NO2 (0.27% (95% CI: 0.01 to 0.54)), which persisted following adjustment for O3 and adjustment for PM2.5. The association appeared to be confined to the midland and southern regions of England and Wales.
Conclusions: The study found no evidence of an association between the modelled pollutants (including components) investigated and STEMI but did find some evidence of a positive association between NO2 and NSTEMI. Confirmation of this association in other studies is required
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