3,781 research outputs found
Viscoelastic properties of green wood across the grain measured by harmonic tests in the range of 0\degree C to 95\degree C. Hardwood vs. softwood and normal wood vs. reaction wood
The viscoelastic properties of wood have been investigated with a dynamic
mechanical analyser (DMA) specifically conceived for wooden materials, the
WAVET device (environmental vibration analyser for wood). Measurements were
carried out on four wood species in the temperature range of 0\degree C to
100\degree C at frequencies varying between 5 mHz and 10 Hz. Wood samples were
tested in water-saturated conditions, in radial and tangential directions. As
expected, the radial direction always revealed a higher storage modulus than
the tangential direction. Great differences were also observed in the loss
factor. The tan\delta peak and the internal friction are higher in tangential
direction than in radial direction. This behaviour is attributed to the fact
that anatomical elements act depending on the direction. Viscoelastic behaviour
of reaction wood differs from that of normal or opposite wood. Compression wood
of spruce, which has higher lignin content, is denser and stiffer in transverse
directions than normal wood, and has lower softening temperature (Tg). In
tension wood, the G-layer is weakly attached to the rest of the wall layers.
This may explain why the storage modulus and the softening temperature of
tension wood are lower than those for the opposite wood. In this work, we also
point out that the time-temperature equivalence fits only around the transition
region, i.e. between Tg and Tg + 30\degree C. Apart from these regions, the
wood response combines the effect of all constitutive polymers, so that the
equivalence is not valid anymore
Halving warming with idealized solar geoengineering moderates key climate hazards
Solar geoengineering (SG) has the potential to restore average surface temperatures by increasing planetary albedo1,2,3,4, but this could reduce precipitation5,6,7. Thus, although SG might reduce globally aggregated risks, it may increase climate risks for some regions8,9,10. Here, using the high-resolution forecast-oriented low ocean resolution (HiFLOR) modelâwhich resolves tropical cyclones and has an improved representation of present-day precipitation extremes11,12âalongside 12 models from the Geoengineering Model Intercomparison Project (GeoMIP), we analyse the fraction of locations that see their local climate change exacerbated or moderated by SG. Rather than restoring temperatures, we assume that SG is applied to halve the warming produced by doubling CO_{2} (half-SG). In HiFLOR, half-SG offsets most of the CO_{2}-induced increase of simulated tropical cyclone intensity. Moreover, neither temperature, water availability, extreme temperature nor extreme precipitation are exacerbated under half-SG when averaged over any Intergovernmental Panel on Climate Change (IPCC) Special Report on Extremes (SREX) region. Indeed, for both extreme precipitation and water availability, less than 0.4% of the ice-free land surface sees exacerbation. Thus, while concerns about the inequality of solar geoengineering impacts are appropriate, the quantitative extent of inequality may be overstated13
Mass Dependence of M3Y-Type Interactions and the Effects of Tensor Correlations
The mass dependence of the M3Y-type effective interactions and the effects of
tensor correlations are examined. Two-body nuclear matrix elements are obtained
by the lowest order constrained variational (LOCV) technique with and without
tensor correlations. We have found that the tensor correlations are important
especially in the triplet-even (TE) and tensor-even (TNE) channels in order to
reproduce the G-matrix elements obtained previously. Then M3Y-type potentials
for inelastic scattering are obtained by fitting our two-body matrix elements
to those of a sum of Yukawa functions for the mass numbers A=24, A=40 and A=90.Comment: 13 pages, 6 table
An occupational therapy intervention for residents with stroke related disabilities in UK care homes (OTCH): cluster randomised controlled trial
Objective To evaluate the clinical efficacy of an established programme of occupational therapy in maintaining functional activity and reducing further health risks from inactivity in care home residents living with stroke sequelae.
Design Pragmatic, parallel group, cluster randomised controlled trial.
Setting 228 care homes (>10 beds each), both with and without the provision of nursing care, local to 11 trial administrative centres across the United Kingdom.
Participants 1042 care home residents with a history of stroke or transient ischaemic attack, including those with language and cognitive impairments, not receiving end of life care. 114 homes (n=568 residents, 64% from homes providing nursing care) were allocated to the intervention arm and 114 homes (n=474 residents, 65% from homes providing nursing care) to standard care (control arm). Participating care homes were randomised between May 2010 and March 2012.
Intervention Targeted three month programme of occupational therapy, delivered by qualified occupational therapists and assistants, involving patient centred goal setting, education of care home staff, and adaptations to the environment.
Main outcome measures Primary outcome at the participant level: scores on the Barthel index of activities of daily living at three months post-randomisation. Secondary outcome measures at the participant level: Barthel index scores at six and 12 months post-randomisation, and scores on the Rivermead mobility index, geriatric depression scale-15, and EuroQol EQ-5D-3L questionnaire, at all time points.
Results 64% of the participants were women and 93% were white, with a mean age of 82.9 years. Baseline characteristics were similar between groups for all measures, personal characteristics, and diagnostic tests. Overall, 2538 occupational therapy visits were made to 498 participants in the intervention arm (mean 5.1 visits per participant). No adverse events attributable to the intervention were recorded. 162 (11%) died before the primary outcome time point, and 313 (30%) died over the 12 months of the trial. The primary outcome measure did not differ significantly between the treatment arms. The adjusted mean difference in Barthel index score at three months was 0.19 points higher in the intervention arm (95% confidence interval â0.33 to 0.70, P=0.48). Secondary outcome measures also showed no significant differences at all time points.
Conclusions This large phase III study provided no evidence of benefit for the provision of a routine occupational therapy service, including staff training, for care home residents living with stroke related disabilities. The established three month individualised course of occupational therapy targeting stroke related disabilities did not have an impact on measures of functional activity, mobility, mood, or health related quality of life, at all observational time points. Providing and targeting ameliorative care in this clinically complex population requires alternative strategies
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Designing live energy performance feedback for public buildings in Leicester
Buildings represent a huge potential for energy savings, in the UK buildings account for 45 % of energy consumption. Buildings owned and managed by the public sector make up more than 10 % of the EU building stock. In recent years there has been much interest in the use of feedback systems to encourage energy behaviour change but very little literature on the design of feedback systems in the non-domestic setting.
The EU âSMARTSPACESâ project is developing ICT services using data generated from smart metering systems in public buildings at 11 pilot sites across Europe. The SMARTSPACES system being developed in the Leicester pilot site will provide users with a live, half-hourly comparison of energy (electricity and gas) performance across 20 public buildings.
A new indicator of energy performance is proposed. The indicator relates consumption for the current half-hour with the distribution of equivalent historical values. The indicator is robust and unambiguous, reflecting progress in energy saving activity, normalised to each building.
The context in which the indicator is presented is also described along with the wider project which is intended to support a change of organisational culture to an active, energy aware community of staff and visitors communicating with energy professionals in the context of ubiquitous building energy performance information
Pathways for nutrient loss to water with emphasis on phosphorus
Teagasc wishes to acknowledge the support of the Environmental Research Technological
Development and Innovation (ERTDI) Programme under the Productive Sector Operational
Programme which was financed by the Irish Government under the National Development
Plan 2000-2006.End of project reportThe main objective of this project was to study phosphorus (P) loss from agricultural land under a range of conditions in Ireland, to quantify the main factors influencing losses and make recommendations on ways to reduce these losses. This report is a synthesis of the main conclusions and recommendations from the results of the studies. The final reports from the individual sub-projects in this project are available from the EPA (www.epa.ie).Environmental Protection Agenc
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