7,550 research outputs found

    The spectral signature of recent climate change

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    Spectrally resolved measurements of the Earth’s reflected shortwave (RSW) and outgoing longwave radiation (OLR) at the top of the atmosphere intrinsically contain the imprints of a multitude of climate relevant parameters. Here, we review the progress made in directly using such observations to diagnose and attribute change within the Earth system over the past four decades. We show how changes associated with perturbations such as increasing greenhouse gases are expected to be manifested across the spectrum and illustrate the enhanced discriminatory power that spectral resolution provides over broadband radiation measurements. Advances in formal detection and attribution techniques and in the design of climate model evaluation exercises employing spectrally resolved data are highlighted. We illustrate how spectral observations have been used to provide insight into key climate feedback processes and quantify multi-year variability but also indicate potential barriers to further progress. Suggestions for future research priorities in this area are provided

    Adoption of "eco-advantage" by SMEs: emerging opportunities and constraints

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    Purpose: A recent study has asserted that businesses need to adopt “eco-advantage”. This paper aims to explore the viability of small and medium enterprises (SMEs) achieving “eco-advantage” by exploring their understanding of sustainability issues, how they adopt and innovate in terms of sustainability and the benefits and obstacles they face. Design/methodology/approach: The research approach is exploratory, comprised of 15 SME embedded cases based in the UK. The cases are participants in short interventions in sustainable product and process design as a part of a university knowledge transfer project, representing the overall case. Cases are based on interviews with company participants and collaborating academics, supplemented by documentary and observational evidence. Findings: The results build on the work on “eco-advantage” found in a recent study, highlighting marketing, rather than compliance issues as a catalyst for change. The newly aware SME enters a development process which involves cumulative capabilities, gaining a nascent inner confidence, which includes espousing wider sustainable values. Research limitations/implications: The results reveal the scope and challenges for SMEs to adopt more sustainable practices, encompassing innovations and a broad set of capabilities. Further research points to the need to monitor benefits as well as inputs in evaluating sustainability improvements and to consider longitudinal business sustainability issues. Originality/value: The paper informs the emerging debate on sustainability in SMEs, providing a rich source of data to enhance the provision of business support and knowledge transfer activities, where a more holistic and customised approach is required to realise the real environmental and economic benefits accrued from implementing sustainable improvements

    Hydrogen peroxide thermochemical oscillator as driver for primordial RNA replication

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    This paper presents and tests a previously unrecognised mechanism for driving a replicating molecular system on the prebiotic earth. It is proposed that cell-free RNA replication in the primordial soup may have been driven by self-sustained oscillatory thermochemical reactions. To test this hypothesis a well-characterised hydrogen peroxide oscillator was chosen as the driver and complementary RNA strands with known association and melting kinetics were used as the substrate. An open flow system model for the self-consistent, coupled evolution of the temperature and concentrations in a simple autocatalytic scheme is solved numerically, and it is shown that thermochemical cycling drives replication of the RNA strands. For the (justifiably realistic) values of parameters chosen for the simulated example system, the mean amount of replicant produced at steady state is 6.56 times the input amount, given a constant supply of substrate species. The spontaneous onset of sustained thermochemical oscillations via slowly drifting parameters is demonstrated, and a scheme is given for prebiotic production of complementary RNA strands on rock surfaces.Comment: Submitted 14 Nov 2013 to J. Roy. Soc. Interface, accepted in final form 25 Feb 2014. An article on this paper appears on https://theconversation.com/au. A new recipe for primordial soup on the pre-biotic earth may help answer questions about the origin of life, and explain why new life does not emerge from non-living precursors on the modern eart

    Regional resilience in recessionary times: a case study of the East Midlands

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    Purpose: Since the 1990's the fashion industry has reflected the issues generally arising in the manufacturing sector, namely rapid and deep structural changes, the development of new supply chain relationships, ICT impacts and increasing globalisation with the attendant issues of ethical sourcing, off-shoring, new emerging markets and recessionary ripples. This paper focuses on one particular aspect of the fashion industry, namely the apparel sector and in particular 'fast fashion' to explore the issues arising for the SMEs in the supply chain. Approach: The research adopts a qualitative methodology and is longitudinal in nature, spanning 5 years from August 2006. The first stage of the research is reported here, where a series of focussed interview scenarios were conducted over an eighteenth month period. The sample of 12 SMEs was a convenience one, drawn from the 30 participants who took part in a business to business event in Leicester, a geographical location which acts as a microcosm of the apparel industry. Interviews were used to elicit narrative data about was what was actually happening in these apparel supply chains. Findings: The apparel supply chain has changed significantly due to recessionary ripples and structural changes. The SMEs have had more success in managing the upstream rather than the downstream relationships and relationships between buyer and suppliers continue to be fractious. Innovation has occurred but is hampered by the relationships that persist. Culture has proved to be a key dimension

    Development of a new generation of high-temperature composite materials

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    Intermetallic matrix composites proposed to meet advanced aeropropulsion requirements are discussed. The powder metallurgy fabrication process currently being used to produce these intermetallic matrix composites will be presented, as will properties of one such composite, SiC/Ti3Al+Nb. In addition, the direction of future research will be outlined, including plans for enhanced fabrication of intermetallic composites by the arc-spray technique and fiber development by the floating-zone process

    A 7-year follow-up of sacral anterior root stimulation for bladder control in patients with a spinal cord injury: quality of life and users' experiences\ud

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    Study design: Cross-sectional descriptive study.\ud \ud Objectives: To assess long-term effects and quality of life (QoL) of using sacral anterior root stimulation (SARS) in spinal cord injured patients.\ud \ud Setting: Neurosurgical and Urological Departments of a large teaching hospital and a large rehabilitation centre in the Netherlands.\ud \ud Methods: In all, 42 patients with complete spinal cord injury (SCI) implanted between 1987 and 2000 were included. A questionnaire was constructed to determine complications, technical failures and personal experiences of the patients. The Qualiveen questionnaire was used and the outcome was compared with data obtained from a reference group of 400 SCI patients with neurogenic bladder problems not using the bladder controller. The Qualiveen questionnaire measures disease-specific aspects in four domains with respect to limitations, constraints, fears and feelings and general QoL aspects, suitable for use in SCI patients with urinary disorders.\ud \ud Results: The results of 37 patients are presented. Our results with the bladder controller with respect to medical and technical complications and infection rates are similar to the results presented by others. From users' experiences, the most important advantages reported were a decreased infection rate (68%), improved social life (54%) and continence (54%). Comparison of the obtained results of our patient group with the Qualiveen questionnaire with a reference group not using the bladder controller indicates that the specific impact of urinary disorders in the four domains on QoL is reduced and that general QoL is improved.\ud \ud Conclusion: SARS is effective and safe for neurogenic bladder management in patients with complete SCI. Users' experiences are positive. Furthermore, this therapy seems to reduce the effects of urinary-disorder-specific QoL aspects, and to increase the QoL in general\u

    Auto-tuning for high performance autopilot design

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    A novel auto-tuning method for the RIDE controller algorithm is presented. The RIDE controller is applied to a high performance aircraft model. The tuner utilises a constrained genetic algorithm to automate the tuning process. The results of the tuner are compared with that of another tuning method which utilises unconstrained optimisation so as to highlight the efficacy of constrained optimisation for this application. It is shown from the results that the constrained genetic algorithm optimisation scheme offers a highly effective tuning solution which can be used to attain safe and high performance control with the RIDE control algorithm
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