928 resultados para compromise
Resumo:
Chain is a commonly used component in offshore moorings where its ruggedness and corrosion resistance make it an attractive choice. Another attractive property is that a straight chain is inherently torque balanced. Having said this, if a chain is loaded in a twisted condition, or twisted when under load, it exhibits highly non-linear torsional behaviour. The consequences of this behaviour can cause handling difficulties or may compromise the integrity of the mooring system, and care must be taken to avoid problems for both the chain and any components to which it is connected. Even with knowledge of the potential problems, there will always be occasions where, despite the utmost care, twist is unavoidable. Thus it is important for the engineer to be able to determine the effects. A frictionless theory has been developed in Part 1 of the paper that may be used to predict the resultant torques and movement or 'lift' in the links as non-dimensional functions of the angle of twist. The present part of the paper describes a series of experiments undertaken on both studless and stud-link chain to allow comparison of this theoretical model with experimental data. Results are presented for the torsional response and link lift for 'constant twist' and 'constant load' type tests on chains of three different link sizes.
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This paper describes a structural design technique for rehabilitation robot intended for upper-limb post-stroke therapy. First, a novel approach to a rehabilitation robot is proposed and the features of the robot are explained. Second, the direct kinematics and the inverse kinematics of the proposed robot structure are derived. Finally, a mechanical design procedure is explained that achieves a compromise between the required motion range and assuring the workspace safety. The suitability of a portable escort type structure for upper limb rehabilitation of both acute and chronic stroke is discussed
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In financial decision-making, a number of mathematical models have been developed for financial management in construction. However, optimizing both qualitative and quantitative factors and the semi-structured nature of construction finance optimization problems are key challenges in solving construction finance decisions. The selection of funding schemes by a modified construction loan acquisition model is solved by an adaptive genetic algorithm (AGA) approach. The basic objectives of the model are to optimize the loan and to minimize the interest payments for all projects. Multiple projects being undertaken by a medium-size construction firm in Hong Kong were used as a real case study to demonstrate the application of the model to the borrowing decision problems. A compromise monthly borrowing schedule was finally achieved. The results indicate that Small and Medium Enterprise (SME) Loan Guarantee Scheme (SGS) was first identified as the source of external financing. Selection of sources of funding can then be made to avoid the possibility of financial problems in the firm by classifying qualitative factors into external, interactive and internal types and taking additional qualitative factors including sovereignty, credit ability and networking into consideration. Thus a more accurate, objective and reliable borrowing decision can be provided for the decision-maker to analyse the financial options.
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The tap-length, or the number of the taps, is an important structural parameter of the linear MMSE adaptive filter. Although the optimum tap-length that balances performance and complexity varies with scenarios, most current adaptive filters fix the tap-length at some compromise value, making them inefficient to implement especially in time-varying scenarios. A novel gradient search based variable tap-length algorithm is proposed, using the concept of the pseudo-fractional tap-length, and it is shown that the new algorithm can converge to the optimum tap-length in the mean. Results of computer simulations are also provided to verify the analysis.
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Gerry Anderson’s 1960s puppet series have hybrid identities in relation to their medial, geographical, and production histories. This chapter ranges over his science fiction series from Supercar (1961) to Joe 90 (1968), arguing that Anderson’s television science fiction in that period crossed many kinds of boundary and border. Anderson’s television series were a compromise between his desire to make films for adults versus an available market for children’s television puppet programs, and aimed to appeal to a cross-generational family audience. They were made on film, using novel effects, for a UK television production culture that still relied largely on live and videotaped production. While commissioned by British ITV companies, the programs had notable success in the USA, achieving national networked screening as well as syndication, and they were designed to be transatlantic products. The transnational hero teams and security organisations featured in the series supported this internationalism, and simultaneously negotiated between the cultural meanings of Britishness and Americanness. By discussing their means of production, the aesthetic and narrative features of the programs, their institutional contexts, and their international distribution, this chapter argues that Anderson’s series suggest ways of rethinking the boundaries of British science fiction television in the 1960s.
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Each year, small Member States receive a disproportionate share of the European Union's (EU's) budget. A prominent explanation for this is that Council decision-making involves a healthy dose of vote selling, whereby large Member States offer small states generous fiscal transfers in exchange for influence over policy. But nobody has investigated whether net budget contributors actually get anything for their money. In this paper I identify the vote selling model's observable implications and find virtually no evidence consistent with Council cash-for-votes exchanges. I also show that a compromise model – the leading model of EU decision-making to date – modified to incorporate vote selling does not outperform a standard one that assumes votes are traded rather than sold. Taken together, the results suggest that Council decision-making operates with little or no vote selling, and that regardless of whatever they think they might be buying, net budget contributors get little or nothing in return for their money. These findings call for further investigation into how Member States approach the issue of fiscal transfers, and into the factors other than formal voting weight that affect the power of actors engaged in EU decision-making.
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Warfarin is a first generation anticoagulant that relies on multiple feeding events to achieve lethality in susceptible rodents. For the Bandicoot rat, warfarin susceptibility baselines were established using the lethal feeding period (LFP) test methodology. Against a 0.003% warfarin formulation, LFP50 values of 2 and 4 days, and LFP99 values of 16 and 10 days were obtained for males and females respectively. However, consumption of rodenticide was significantly reduced after the 4th and 5th days of test, at a time when animals would be expected to experience symptoms of warfarin toxicity. This would seriously compromise the Probit analysis, particularly for estimates of higher percentiles. Possible modifications to the methodology are discussed to overcome this problem. Although the majority of animals were highly susceptible to warfarin, one female animal that survived a high dose of active ingredient (79.1 mg kg-1) may bode for future resistance
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The United Nation Intergovernmental Panel on Climate Change (IPCC) makes it clear that climate change is due to human activities and it recognises buildings as a distinct sector among the seven analysed in its 2007 Fourth Assessment Report. Global concerns have escalated regarding carbon emissions and sustainability in the built environment. The built environment is a human-made setting to accommodate human activities, including building and transport, which covers an interdisciplinary field addressing design, construction, operation and management. Specifically, Sustainable Buildings are expected to achieve high performance throughout the life-cycle of siting, design, construction, operation, maintenance and demolition, in the following areas: • energy and resource efficiency; • cost effectiveness; • minimisation of emissions that negatively impact global warming, indoor air quality and acid rain; • minimisation of waste discharges; and • maximisation of fulfilling the requirements of occupants’ health and wellbeing. Professionals in the built environment sector, for example, urban planners, architects, building scientists, engineers, facilities managers, performance assessors and policy makers, will play a significant role in delivering a sustainable built environment. Delivering a sustainable built environment needs an integrated approach and so it is essential for built environment professionals to have interdisciplinary knowledge in building design and management . Building and urban designers need to have a good understanding of the planning, design and management of the buildings in terms of low carbon and energy efficiency. There are a limited number of traditional engineers who know how to design environmental systems (services engineer) in great detail. Yet there is a very large market for technologists with multi-disciplinary skills who are able to identify the need for, envision and manage the deployment of a wide range of sustainable technologies, both passive (architectural) and active (engineering system),, and select the appropriate approach. Employers seek applicants with skills in analysis, decision-making/assessment, computer simulation and project implementation. An integrated approach is expected in practice, which encourages built environment professionals to think ‘out of the box’ and learn to analyse real problems using the most relevant approach, irrespective of discipline. The Design and Management of Sustainable Built Environment book aims to produce readers able to apply fundamental scientific research to solve real-world problems in the general area of sustainability in the built environment. The book contains twenty chapters covering climate change and sustainability, urban design and assessment (planning, travel systems, urban environment), urban management (drainage and waste), buildings (indoor environment, architectural design and renewable energy), simulation techniques (energy and airflow), management (end-user behaviour, facilities and information), assessment (materials and tools), procurement, and cases studies ( BRE Science Park). Chapters one and two present general global issues of climate change and sustainability in the built environment. Chapter one illustrates that applying the concepts of sustainability to the urban environment (buildings, infrastructure, transport) raises some key issues for tackling climate change, resource depletion and energy supply. Buildings, and the way we operate them, play a vital role in tackling global greenhouse gas emissions. Holistic thinking and an integrated approach in delivering a sustainable built environment is highlighted. Chapter two demonstrates the important role that buildings (their services and appliances) and building energy policies play in this area. Substantial investment is required to implement such policies, much of which will earn a good return. Chapters three and four discuss urban planning and transport. Chapter three stresses the importance of using modelling techniques at the early stage for strategic master-planning of a new development and a retrofit programme. A general framework for sustainable urban-scale master planning is introduced. This chapter also addressed the needs for the development of a more holistic and pragmatic view of how the built environment performs, , in order to produce tools to help design for a higher level of sustainability and, in particular, how people plan, design and use it. Chapter four discusses microcirculation, which is an emerging and challenging area which relates to changing travel behaviour in the quest for urban sustainability. The chapter outlines the main drivers for travel behaviour and choices, the workings of the transport system and its interaction with urban land use. It also covers the new approach to managing urban traffic to maximise economic, social and environmental benefits. Chapters five and six present topics related to urban microclimates including thermal and acoustic issues. Chapter five discusses urban microclimates and urban heat island, as well as the interrelationship of urban design (urban forms and textures) with energy consumption and urban thermal comfort. It introduces models that can be used to analyse microclimates for a careful and considered approach for planning sustainable cities. Chapter six discusses urban acoustics, focusing on urban noise evaluation and mitigation. Various prediction and simulation methods for sound propagation in micro-scale urban areas, as well as techniques for large scale urban noise-mapping, are presented. Chapters seven and eight discuss urban drainage and waste management. The growing demand for housing and commercial developments in the 21st century, as well as the environmental pressure caused by climate change, has increased the focus on sustainable urban drainage systems (SUDS). Chapter seven discusses the SUDS concept which is an integrated approach to surface water management. It takes into consideration quality, quantity and amenity aspects to provide a more pleasant habitat for people as well as increasing the biodiversity value of the local environment. Chapter eight discusses the main issues in urban waste management. It points out that population increases, land use pressures, technical and socio-economic influences have become inextricably interwoven and how ensuring a safe means of dealing with humanity’s waste becomes more challenging. Sustainable building design needs to consider healthy indoor environments, minimising energy for heating, cooling and lighting, and maximising the utilisation of renewable energy. Chapter nine considers how people respond to the physical environment and how that is used in the design of indoor environments. It considers environmental components such as thermal, acoustic, visual, air quality and vibration and their interaction and integration. Chapter ten introduces the concept of passive building design and its relevant strategies, including passive solar heating, shading, natural ventilation, daylighting and thermal mass, in order to minimise heating and cooling load as well as energy consumption for artificial lighting. Chapter eleven discusses the growing importance of integrating Renewable Energy Technologies (RETs) into buildings, the range of technologies currently available and what to consider during technology selection processes in order to minimise carbon emissions from burning fossil fuels. The chapter draws to a close by highlighting the issues concerning system design and the need for careful integration and management of RETs once installed; and for home owners and operators to understand the characteristics of the technology in their building. Computer simulation tools play a significant role in sustainable building design because, as the modern built environment design (building and systems) becomes more complex, it requires tools to assist in the design process. Chapter twelve gives an overview of the primary benefits and users of simulation programs, the role of simulation in the construction process and examines the validity and interpretation of simulation results. Chapter thirteen particularly focuses on the Computational Fluid Dynamics (CFD) simulation method used for optimisation and performance assessment of technologies and solutions for sustainable building design and its application through a series of cases studies. People and building performance are intimately linked. A better understanding of occupants’ interaction with the indoor environment is essential to building energy and facilities management. Chapter fourteen focuses on the issue of occupant behaviour; principally, its impact, and the influence of building performance on them. Chapter fifteen explores the discipline of facilities management and the contribution that this emerging profession makes to securing sustainable building performance. The chapter highlights a much greater diversity of opportunities in sustainable building design that extends well into the operational life. Chapter sixteen reviews the concepts of modelling information flows and the use of Building Information Modelling (BIM), describing these techniques and how these aspects of information management can help drive sustainability. An explanation is offered concerning why information management is the key to ‘life-cycle’ thinking in sustainable building and construction. Measurement of building performance and sustainability is a key issue in delivering a sustainable built environment. Chapter seventeen identifies the means by which construction materials can be evaluated with respect to their sustainability. It identifies the key issues that impact the sustainability of construction materials and the methodologies commonly used to assess them. Chapter eighteen focuses on the topics of green building assessment, green building materials, sustainable construction and operation. Commonly-used assessment tools such as BRE Environmental Assessment Method (BREEAM), Leadership in Energy and Environmental Design ( LEED) and others are introduced. Chapter nineteen discusses sustainable procurement which is one of the areas to have naturally emerged from the overall sustainable development agenda. It aims to ensure that current use of resources does not compromise the ability of future generations to meet their own needs. Chapter twenty is a best-practice exemplar - the BRE Innovation Park which features a number of demonstration buildings that have been built to the UK Government’s Code for Sustainable Homes. It showcases the very latest innovative methods of construction, and cutting edge technology for sustainable buildings. In summary, Design and Management of Sustainable Built Environment book is the result of co-operation and dedication of individual chapter authors. We hope readers benefit from gaining a broad interdisciplinary knowledge of design and management in the built environment in the context of sustainability. We believe that the knowledge and insights of our academics and professional colleagues from different institutions and disciplines illuminate a way of delivering sustainable built environment through holistic integrated design and management approaches. Last, but not least, I would like to take this opportunity to thank all the chapter authors for their contribution. I would like to thank David Lim for his assistance in the editorial work and proofreading.
Resumo:
Near-isogenic lines (NILs) of winter wheat varying for alleles for reduced height (Rht), gibberellin (GA) response and photoperiod insensitivity (Ppd-D1a) in cv. Mercia background (rht (tall), Rht-B1b, Rht-D1b, Rht-B1c, Rht8c+Ppd-D1a, Rht-D1c, Rht12) and cv. Maris Widgeon (rht (tall), Rht-D1b, Rht-B1c) backgrounds were compared to investigate main effects and interactions with tillage (plough-based, minimum-, and zero-tillage) over two years. Both minimum- and zero- tillage were associated with reduced grain yields allied to reduced harvest index, biomass accumulation, interception of photosynthetically active radiation (PAR), and plant populations. Grain yields were optimized at mature crop heights of around 740mm because this provided the best compromise between harvest index which declined with height, and above ground biomass which increased with height. Improving biomass with height was due to improvements in both PAR interception and radiation-use efficiency. Optimum height for grain yield was unaffected by tillage system or GA-sensitivity. After accounting for effects of height, GA insensitivity was associated with increased grain yields due to increased grains per spike, which was more than enough to compensate for poorer plant establishment and lower mean grain weights compared to the GA-sensitive lines. Although better establishment was possible with GA-sensitive lines, there was no evidence that this effect interacted with tillage method. We find, therefore, little evidence to question the current adoption of wheats with reduced sensitivity to GA in the UK, even as tillage intensity lessens.
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This is vol. I of my two-volume study of the nuclear strategies/strategy preferences of NATO collectively, and individually of Britain, France, and West Germany in the Cold War. It shows that NATO strategy was a fragile compromise, and that these three countries, all within range of Soviet medium/intermediate range nuclear missiles and thus with less geostrategic difference than in previous military threat contexts, had wildly divergent strategies/preferences which cannot be explained merely by geography. It raises the question of what made them so different, addressed in Volume II "Nuclear Mentalities" (q.v.)
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One definition of food security is having sufficient, safe, and nutritious food to meet dietary needs. This paper highlights the role of plant mineral nutrition in food production, delivering of essential mineral elements to the human diet, and preventing harmful mineral elements entering the food chain. To maximise crop production, the gap between actual and potential yield must be addressed. This gap is 15–95% of potential yield, depending on the crop and agricultural system. Current research in plant mineral nutrition aims to develop appropriate agronomy and improved genotypes, for both infertile and productive soils, that allow inorganic and organic fertilisers to be utilised more efficiently. Mineral malnutrition affects two-thirds of the world's population. It can be addressed by the application of fertilisers, soil amelioration, and the development of genotypes that accumulate greater concentrations of mineral elements lacking in human diets in their edible tissues. Excessive concentrations of harmful mineral elements also compromise crop production and human health. To reduce the entry of these elements into the food chain, strict quality requirements for fertilisers might be enforced, agronomic strategies employed to reduce their phytoavailability, and crop genotypes developed that do not accumulate high concentrations of these elements in edible tissues.
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Each human body plays host to a microbial population which is both numerically vast (at around 1014 microbial cells) and phenomenally diverse (over 1,000 species). The majority of the microbial species in the gut have not been cultured but the application of culture-independent approaches for high throughput diversity and functionality analysis has allowed characterisation of the diverse microbial phylotypes present in health and disease. Studies in monozygotic twins, showing that these retain highly similar microbiota decades after birth and initial colonisation, are strongly indicative that diversity of the microbiome is host-specific and affected by the genotype. Microbial diversity in the human body is reflected in both richness and evenness. Diversity increases steeply from birth reaching its highest point in early adulthood, before declining in older age. However, in healthy subjects there appears to be a core of microbial phylotypes which remains relatively stable over time. Studies of individuals from diverse geopraphies suggest that clusters of intestinal bacterial groups tend to occur together, constituting ‘enterotypes’. So variation in intestinal microbiota is stratified rather than continuous and there may be a limited number of host/microbial states which respond differently to environmental influences. Exploration of enterotypes and functional groups may provide biomarkers for disease and insights into the potential for new treatments based on manipulation of the microbiome. In health, the microbiota interact with host defences and exist in harmonious homeostasis which can then be disturbed by invading organisms or when ‘carpet bombing’ by antibiotics occurs. In a portion of individuals with infections, the disease will resolve itself without the need for antibiotics and microbial homeostasis with the host’s defences is restored. The administration of probiotics (live microorganisms which when administered in adequate amounts confer a health benefit on the host) represents an artificial way to enhance or stimulate these natural processes. The study of innate mechanisms of antimicrobial defence on the skin, including the production of numerous antimicrobial peptides (AMPs), has shown an important role for skin commensal organisms. These organisms may produce AMPs, and also amplify the innate immune responses to pathogens by activating signalling pathways and processing host produced AMPs. Research continues into how to enhance and manipulate the role of commensal organisms on the skin. The challenges of skin infection (including diseases caused by multiply resistant organisms) and infestations remain considerable. The potential to re-colonise the skin to replace or reduce pathogens, and exploring the relationship between microbiota elsewhere and skin diseases are among a growing list of research targets. Lactobacillus species are among the best known ‘beneficial’ bacterial members of the human microbiota. Of the approximately 120 species known, about 15 are known to occur in the human vagina. These organisms have multiple properties, including the production of lactic acid, hydrogen peroxide and bacteriocins, which render the vagina inhospitable to potential pathogens. Depletion of the of the normal Lactobacillus population and overgrowth of vaginal anaerobes, accompanied by the loss of normal vaginal acidity can lead to bacterial vaginosis – the commonest cause of abnormal vaginal discharge in women. Some vaginal anaerobes are associated with the formation of vaginal biofilms which serve to act as a reservoir of organisms which persists after standard antibiotic therapy of bacterial vaginosis and may help to account for the characteristically high relapse rate in the condition. Administration of Lactobacillus species both vaginally and orally have shown beneficial effects in the treatment of bacterial vaginosis and such treatments have an excellent overall safety record. Candida albicans is a frequent coloniser of human skin and mucosal membranes, and is a normal part of the microbiota in the mouth, gut and vagina. Nevertheless Candida albicans is the most common fungal pathogen worldwide and is a leading cause of serious and often fatal nosocomial infections. What turns this organism from a commensal to a pathogen is a combination of increasing virulence in the organism and predisposing host factors that compromise immunity. There has been considerable research into the use of probiotic Lactobacillus spp. in vaginal candidiasis. Studies in reconstituted human epithelium and monolayer cell cultures have shown that L. rhamnosus GG can protect mucosa from damage caused by Candida albicans, and enhance the immune responses of mucosal surfaces. Such findings offer the promise that the use of such probiotic bacteria could provide new options for antifungal therapy. Studies of changes of the human intestinal microbiota in health and disease are complicated by its size and diversity. The Alimentary Pharmabiotic Centre in Cork (Republic of Ireland) has the mission to ‘mine microbes for mankind’ and its work illustrates the potential benefits of understanding the gut microbiota. Work undertaken at the centre includes: mapping changes in the microbiota with age; studies of the interaction between the microbiota and the gut; potential interactions between the gut microbiota and the central nervous system; the potential for probiotics to act as anti-infectives including through the production of bacteriocins; and the characterisation of interactions between gut microbiota and bile acids which have important roles as signalling molecules and in immunity. The important disease entity where the role of the gut microbiota appears to be central is the Irritable Bowel Syndrome (IBS). IBS patients show evidence of immune activation, impaired gut barrier function and abnormal gut microbiota. Studies with probiotics have shown that these organisms can exert anti-inflammatory effects in inflammatory bowel disease and may strengthen the gut barrier in IBS of the diarrhoea-predominant type. Formal randomised trials of probiotics in IBS show mixed results with limited benefit for some but not all. Studies confirm that administered probiotics can survive and temporarily colonise the gut. They can also stimulate the numbers of other lactic acid bacilli in the gut, and reduce the numbers of pathogens. However consuming live organisms is not the only way to influence gut microbiota. Dietary prebiotics are selectively fermented ingredients that can change the composition and/or activity of the gastrointestinal microbiota in beneficial ways. Dietary components that reach the colon, and are available to influence the microbiota include poorly digestible carbohydrates, such as non-starch polysaccharides, resistant starch, non-digestible oligosaccharides (NDOs) and polyphenols. Mixtures of probiotic and prebiotic ingredients that can selectively stimulate growth or activity of health promoting bacteria have been termed ‘synbiotics’. All of these approaches can influence gut microbial ecology, mainly to increase bifidobacteria and lactobacilli, but metagenomic approaches may reveal wider effects. Characterising how these changes produce physiological benefits may enable broader use of these tactics in health and disease in the future. The current status of probiotic products commercially available worldwide is less than ideal. Prevalent problems include misidentification of ingredient organisms and poor viability of probiotic microorganisms leading to inadequate shelf life. On occasions these problems mean that some commercially available products cannot be considered to meet the definition of a probiotic product. Given the potential benefits of manipulating the human microbiota for beneficial effects, there is a clear need for improved regulation of probiotics. The potential importance of the human microbiota cannot be overstated. ‘We feed our microbes, they talk to us and we benefit. We just have to understand and then exploit this.’ (Willem de Vos).
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The low-molecular-weight (LMW) glutenin subunits are components of the highly cross-linked glutenin polymers that confer viscoelastic properties to gluten and dough. They have both quantitative and qualitative effects on dough quality that may relate to differences in their ability to form the inter-chain disulphide bonds that stabilise the polymers. In order to determine the relationship between dough quality and the amounts and properties of the LMW subunits, we have transformed the pasta wheat cultivars Svevo and Ofanto with three genes encoding proteins, which differ in their numbers or positions of cysteine residues. The transgenes were delivered under control of the high-molecular-weight (HMW) subunit 1Dx5 gene promoter and terminator regions, and the encoded proteins were C-terminally tagged by the introduction of the c-myc epitope. Stable transformants were obtained with both cultivars, and the use of a specific antibody to the c-myc epitope tag allowed the transgene products to be readily detected in the complex mixture of LMW subunits. A range of transgene expression levels was observed. The addition of the epitope tag did not compromise the correct folding of the trangenic subunits and their incorporation into the glutenin polymers. Our results demonstrate that the ability to specifically epitope-tag LMW glutenin transgenes can greatly assist in the elucidation of their individual contributions to the functionality of the complex gluten system.
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We describe development of a questionnaire to elicit pain symptoms and experience, for use by people with dementia or their carers, at hospital admission. The questionnaire provided contextual information to support professionals’ use of the Abbey Pain Scale, a validated tool used by nursing staff internationally. Appropriate information and physical design were required in order, not only to create an approachable questionnaire for patients and carers, but also to ensure fit with hospital processes. Fit with hospital process had significant influence on the final form of the questionnaire, compromising some aspects of design for patients and carers, but this compromise was considered essential to ensure pain management procedures were supplemented by wider, contextual information.
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The endocannabinoid system (ECS) was only 'discovered' in the 1990s. Since then, many new ligands have been identified, as well as many new intracellular targets--ranging from the PPARs, to mitochondria, to lipid rafts. It was thought that blocking the CB-1 receptor might reverse obesity and the metabolic syndrome. This was based on the idea that the ECS was dysfunctional in these conditions. This has met with limited success. The reason may be that the ECS is a homeostatic system, which integrates energy seeking and storage behaviour with resistance to oxidative stress. It could be viewed as having thrifty actions. Thriftiness is an innate property of life, which is programmed to a set point by both environment and genetics, resulting in an epigenotype perfectly adapted to its environment. This thrifty set point can be modulated by hormetic stimuli, such as exercise, cold and plant micronutrients. We have proposed that the physiological and protective insulin resistance that underlies thriftiness encapsulates something called 'redox thriftiness', whereby insulin resistance is determined by the ability to resist oxidative stress. Modern man has removed most hormetic stimuli and replaced them with a calorific sedentary lifestyle, leading to increased risk of metabolic inflexibility. We suggest that there is a tipping point where lipotoxicity in adipose and hepatic cells induces mild inflammation, which switches thrifty insulin resistance to inflammation-driven insulin resistance. To understand this, we propose that the metabolic syndrome could be seen from the viewpoint of the ECS, the mitochondrion and the FOXO group of transcription factors. FOXO has many thrifty actions, including increasing insulin resistance and appetite, suppressing oxidative stress and shifting the organism towards using fatty acids. In concert with factors such as PGC-1, they also modify mitochondrial function and biogenesis. Hence, the ECS and FOXO may interact at many points; one of which may be via intracellular redox signalling. As cannabinoids have been shown to modulate reactive oxygen species production, it is possible that they can upregulate anti-oxidant defences. This suggests they may have an 'endohormetic' signalling function. The tipping point into the metabolic syndrome may be the result of a chronic lack of hormetic stimuli (in particular, physical activity), and thus, stimulus for PGC-1, with a resultant reduction in mitochondrial function and a reduced lipid capacitance. This, in the context of a positive calorie environment, will result in increased visceral adipose tissue volume, abnormal ectopic fat content and systemic inflammation. This would worsen the inflammatory-driven pathological insulin resistance and inability to deal with lipids. The resultant oxidative stress may therefore drive a compensatory anti-oxidative response epitomised by the ECS and FOXO. Thus, although blocking the ECS (e.g. via rimonabant) may induce temporary weight loss, it may compromise long-term stress resistance. Clues about how to modulate the system more safely are emerging from observations that some polyphenols, such as resveratrol and possibly, some phytocannabinoids, can modulate mitochondrial function and might improve resistance to a modern lifestyle.