Green Guide to Composites: an environmental profiling system for composite materials and products

Products made from composite materials can offer significant environmental benefits because of their characteristically low weight, good mechanical properties and excellent resistance to corrosion. For example, composites used in cars can reduce the overall weight of the car and so offer fuel savings through the lifetime of the vehicle. However, although the in-service environmental benefits of composites are known, there is far less understanding of the environmental and social implications associated with the manufacture of composite materials and products. Issues affecting the industry include health and safety, the emission of volatile organic compounds (VOCs), energy consumption and toxicity from manufacture. Alternative materials and technologies (such as closed mould processes, natural fibres and low-styrene resins) have been developed to address these problems, but to date there has still been confusion within the industry as to the detailed benefits of these alternatives. This guide has been created to enable the composites sector to understand the environmental and social impacts associated with composite production and assist with the decisions made about material and process choice. The materials and processes modelled are rated from A (good) through to E (poor). Twelve different environmental impacts are individually scored and totalled to give an overall environmental impact summary rating. Two social impact ratings are also given. When measuring environmental impact it is important to consider all the influences through the life of the product. This process is known as Life Cycle Assessment (LCA) and it has been used in this guide for environmental investigation. Because this guide concentrates on materials and manufacturing, as opposed to in-service performance, the impacts associated with products beyond the factory gate (the use, maintenance and disposal stages of the life cycle) have not been assessed. Within the system boundaries for the LCA, three typical product types have been chosen to reflect a range of different components commonly manufactured using composites: • A double curvature panel – this has a surface area of 1m2 with a panel stiffness equivalent to a 4mm thick chopped strand mat laminate. • A flat sandwich panel – measuring 1m x 8m with a 25mm thick core, having a panel bending stiffness equivalent to a sandwich panel with a 4mm thick chopped strand mat skin. • A complex moulded component – with a volume of 770cm3. Similarly, production processes and materials have been selected to provide a balance between systems that are commonly used across the majority of the composites industry and emerging materials with the potential to provide an environmental benefit. For this reason, materials such as hemp fibre and self-reinforced polypropylene have been included in the guide, but materials that are more specific to a single sector (eg aramid fibre) have not been included. Within each specific process there are still many processing variations (eg methods for mixing, curing and trimming) in addition to the material choice possibilities. To enable fair comparisons, a base case has been selected for each process. This is used throughout the guide to allow the merits of each process variation to be assessed

Time trials versus time to exhaustion tests: Effects on critical 1 power, W′ and oxygen uptake kinetics

Purpose: To investigate single-day time-to-exhaustion (TTE) and time trial (TT) based laboratory tests values of critical power (CP), Wprime (W') and respective oxygen kinetics responses. Methods: Twelve cyclists performed a maximal ramp test followed by three TTE and three TT efforts interspersed by a 60-min recovery between efforts. Oxygen uptake was measured during all trials. The mean response time (MRT) was calculated as a description of the overall V ̇O2 kinetic response from the onset to 2 min of exercise. Results: TTE determined CP was 279 ± 52W and TT determined CP was 276 ± 50W (P = 0.237). Values of W were 14.3 ± 3.4 kJ (TTE W') and 16.5± 4.2 kJ (TT W') (P = 0.028). Whilst a high level of agreement (-12 to 17 W) and a low prediction error of 2.7% was established for CP, for W limits of agreements were markedly lower (-8 to 3.7 kJ) with a prediction error of 18.8%. The mean standard error for TTE CP values was significantly higher than that for TT CP values (2.4 ± 1.9% vs. 1.2 ± 0.7% W). The standard error for TTE W and TT W were 11.2 ± 8.1% and 5.6 ± 3.6%, respectively. The V ̇O2 response was significantly faster during TT (~22 s) than TTE (~28 s). Conclusions: The time-trial protocol with a 60-min recovery period offers a valid, time-saving and less error containing alternative to conventional and more recent testing methods. Results however cannot be transferred to W'

Spin-Peierls Dimerization of a s=1/2 Heisenberg Antiferromagnet on a Square Lattice

Dimerization of a spin-half Heisenberg antiferromagnet on a square lattice is investigated for several possible dimerized configurations, some of which are shown to have lower ground state energies than the others. In particular, the lattice deformations resulting in alternate stronger and weaker couplings along both the principal axes of a square lattice are shown to result in a larger gain in magnetic energy. In addition, a `columnar' configuration is shown to have a lower ground state energy and a faster increase in the energy gap parameter than a `staggered' configuration. The inclusion of unexpanded exchange coupling leads to a power law behaviour for the magnetic energy gain and energy gap, which is qualitatively different from that reported earlier. Instead of increasing as $\delta ^{x}$, the two quantities depend on $\delta$ as $\delta ^{\nu}/| \ln \delta | .$ This is true both in the near critical regime $(0\leq \delta \leq 0.1)$ as well as in the far regime $(0\leq \delta <1)$. It is suggested that the unexpanded exchange coupling is as much a source of the logarithmic dependence as a correction due to the contribution of umklapp processes. Staggered magnetization is shown to follow the same $\delta$-dependence in all the configurations in the small $\delta$-regime, while for $0\leq \delta <1$, it follows the power law $\delta ^{x}$.Comment: 12 pages, 7 Postscript figures, RevTex forma

What can clinical leaders contribute to the governance of integrated care systems?

Background: Integrated care systems present enduring governance challenges associated with fostering interorganisational collaboration. Aim: To understand how clinical leaders can make a distinct contribution to the governance and system leadership of integrated care systems. Methods: A qualitative interview study carried out between 2018 and 2019 with 24 clinical leaders, and a further 47 non-clinical leaders, involved in the governance of three Sustainability and Transformation Partnership in the English National Health Service. Results: Clinical leaders were found to make four distinct contributions: (1) making analytical insights into integration strategies that ensured their relevance and quality to clinical communities; (2) representing the views of clinicians in system decision-making thereby enhancing the legitimacy of change; (3) translation and communication activities to articulate integration strategies in favourable ways and ensure clinical engagement; and (4) relational work in the form of brokering and building connections and mediating conflict between multiple stakeholders. These activities varied across the levels of system governance and at different stages in the processes of change. Conclusions: Clinical leaders can make a distinct contribution to the governance and leadership of integrated care systems based on their clinical expertise, membership professional networks, reputation and formal authority

Acceptability of a vocational advice service for patients consulting in primary care with musculoskeletal pain: A qualitative exploration of the experiences of general practitioners, vocational advisers and patients

Aims: To explore the experiences of GPs, vocational advisors and patients towards a new vocational advice (VA) service in primary care, using qualitative interviews. Methods This study was nested within the Study of Work And Pain (SWAP) cluster randomised controlled trial. The SWAP trial located a VA service within three general practices in Staffordshire. Interviews took place with 10 GPs 12 months after the introduction of the VA service, 4 vocational advisors whilst the VA service was running and 20 patients on discharge from the VA service. The data were analysed using the 'constant comparative' method, which is a variation of grounded theory. Results: The key factors determining the acceptability and perceived effectiveness of the VA service from the perspective of the three groups of stakeholders were 1) the timing of referrals to the VA, 2) the perceived lack of patient demand for the service, and 3) role uncertainty experienced by VAs. Conclusions: Early vocational intervention may not be appropriate for all musculoskeletal patients with work difficulties. Indeed, many patients felt they did not require the support of a VA, either because they had self-limiting work difficulties and/or already had support mechanisms in place to return to work. Future VA interventions may be better implemented in a targeted way so that appropriate patients are identified with characteristics which can best be addressed by the VA service

The role of metaphor in shaping the identity and agenda of the United Nations: the imagining of an international community and international threat

This article examines the representation of the United Nations in speeches delivered by its Secretary General. It focuses on the role of metaphor in constructing a common ‘imagining’ of international diplomacy and legitimising an international organisational identity. The SG legitimises the organisation, in part, through the delegitimisation of agents/actions/events constructed as threatening to the international community and to the well-being of mankind. It is a desire to combat the forces of menace or evil which are argued to motivate and determine the organisational agenda. This is predicated upon an international ideology of humanity in which difference is silenced and ‘working towards the common good’ is emphasised. This is exploited to rouse emotions and legitimise institutional power. Polarisation and antithesis are achieved through the employment of metaphors designed to enhance positive and negative evaluations. The article further points to the constitutive, persuasive and edifying power of topic and situationally-motivated metaphors in speech-making

Immunization of Mice With Vibrio cholerae Outer-Membrane Vesicles Protects Against Hyperinfectious Challenge and Blocks Transmission

Background. Vibrio cholerae excreted by cholera patients is “hyperinfectious” (HI), which can be modeled by passage through infant mice. Immunization of adult female mice with V. cholerae outer-membrane vesicles (OMVs) passively protects suckling mice from challenge. Although V. cholerae is unable to colonize protected pups, the bacteria survive passage and have the potential to be transmitted to susceptible individuals. Here, we investigated the impact of OMV immunization and the HI state on V. cholerae transmission

SARS Risk Perception, Knowledge, Precautions, and Information Sources, the Netherlands

Severe acute respiratory syndrome (SARS)–related risk perceptions, knowledge, precautionary actions, and information sources were studied in the Netherlands during the 2003 SARS outbreak. Although respondents were highly aware of the SARS outbreak, the outbreak did not result in unnecessary precautionary actions or fears

Whole genome sequencing increases molecular diagnostic yield compared with current diagnostic testing for inherited retinal disease

Abstract not availableJamie M. Ellingford, Stephanie Barton, Sanjeev Bhaskar, Simon G. Williams, Panagiotis I. Sergouniotis, James O, Sullivan, Janine A. Lamb, Rahat Perveen, Georgina Hall, William G. Newman, Paul N. Bishop, Stephen A. Roberts, Rick Leach, Rick Tearle, Stuart Bayliss, Simon C. Ramsden, Andrea H. Nemeth, Graeme C.M. Blac