288 research outputs found

    'If it's a medical issue I would have covered it by now': learning about fibromyalgia through the hidden curriculum: a qualitative study

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    BACKGROUND: Fibromyalgia syndrome (FMS) is a long-term condition that affects between 1 and 5% of the general population and lies within the spectrum of medically unexplained symptoms (MUS). FMS can be difficult to diagnose and is usually done so as a diagnosis of exclusion. There is continuing debate regarding its legitimacy excluding other causes of symptoms. It is known that the diagnosis and management of MUS, including FMS, receives little attention in medical curricula and attitudes towards patients with FMS amongst medical professionals and trainees can be negative. The purpose of this study was to investigate how attitudes and perspectives of undergraduate medical students towards FMS are acquired during their training. METHODS: Qualitative interviews with 21 medical students were conducted to explore their views on FMS, encounters with patients with FMS, and where learning about FMS occurs. Participants were recruited from two English medical schools and the study was approved by two University Ethics committees. Interviews were digitally recorded with consent and data analysed thematically, using principles of constant comparison. RESULTS: The data were organised within three themes: i) FMS is a complex, poorly understood condition; ii) multiple sources for learning about FMS; and iii) consequences of negative attitudes for patients with FMS. CONCLUSION: Undergraduate medical students have limited understanding of, and are sceptical over the existence of FMS. These attitudes are influenced by the 'hidden curriculum' and witnessing attitudes and actions of their clinical teachers. Students interpret a lack of formal curriculum teaching around FMS to mean that it is not serious and hence a low priority. Encountering a patient, friend or family member with FMS can increase knowledge and lead to altered perceptions of the condition. Teaching and learning about FMS needs to be consistent to improve knowledge and attitudes of clinicians. Undergraduate students should be exposed to patients with FMS so that they better understand patients with FMS

    Constant amplitude and post-overload fatigue crack growth behavior in PM aluminum alloy AA 8009

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    A recently developed, rapidly solidified, powder metallurgy, dispersion strengthened aluminum alloy, AA 8009, was fatigue tested at room temperature in lab air. Constant amplitude/constant delta kappa and single spike overload conditions were examined. High fatigue crack growth rates and low crack closure levels compared to typical ingot metallurgy aluminum alloys were observed. It was proposed that minimal crack roughness, crack path deflection, and limited slip reversibility, resulting from ultra-fine microstructure, were responsible for the relatively poor da/dN-delta kappa performance of AA 8009 as compared to that of typical IM aluminum alloys

    Environmental risk assessment of genetically modified plants - concepts and controversies

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    Background and purpose: In Europe, the EU Directive 2001/18/EC lays out the main provisions of environmental risk assessment (ERA) of genetically modified (GM) organisms that are interpreted very differently by different stakeholders. The purpose of this paper is to: (a) describe the current implementation of ERA of GM plants in the EU and its scientific shortcomings, (b) present an improved ERA concept through the integration of a previously developed selection procedure for identification of non-target testing organisms into the ERA framework as laid out in the EU Directive 2001/18/EC and its supplement material (Commission Decision 2002/623/EC), (c) describe the activities to be carried out in each component of the ERA and (d) propose a hierarchical testing scheme. Lastly, we illustrate the outcomes for three different crop case examples. Main features: Implementation of the current ERA concept of GM crops in the EU is based on an interpretation of the EU regulations that focuses almost exclusively on the isolated bacteria-produced novel proteins with little consideration of the whole plant. Therefore, testing procedures for the effect assessment of GM plants on non-target organisms largely follow the ecotoxicological testing strategy developed for pesticides. This presumes that any potential adverse effect of the whole GM plant and the plant-produced novel compound can be extrapolated from testing of the isolated bacteriaproduced novel compound or can be detected in agronomic field trials. This has led to persisting scientific criticism. Results: Based on the EU ERA framework, we present an improved ERA concept that is system oriented with the GM plant at the centre and integrates a procedure for selection of testing organisms that do occur in the receiving environment. We also propose a hierarchical testing scheme from laboratory studies to field trials and we illustrate the outcomes for three different crop case examples. Conclusions and recommendations: Our proposed concept can alleviate a number of deficits identified in the current approach to ERA of GM plants. It allows the ERA to be tailored to the GM plant case and the receiving environment

    Microscopy techniques for determining water-cement (w/c) ratio in hardened concrete: A round-robin assessment

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    Water to cement (w/c) ratio is usually the most important parameter specified in concrete design and is sometimes the subject of dispute when a shortfall in concrete strength or durability is an issue. However, determination of w/c ratio in hardened concrete by testing is very difficult once the concrete has set. This paper presents the results from an inter-laboratory round-robin study organised by the Applied Petrography Group to evaluate and compare microscopy methods for measuring w/c ratio in hardened concrete. Five concrete prisms with w/c ratios ranging from 0.35 to 0.55, but otherwise identical in mix design were prepared independently and distributed to 11 participating petrographic laboratories across Europe. Participants used a range of methods routine to their laboratory and these are broadly divided into visual assessment, measurement of fluorescent intensity and quantitative backscattered electron microscopy. Some participants determined w/c ratio using more than one method or operator. Consequently, 100 individual w/c ratio determinations were collected, representing the largest study of its type ever undertaken. The majority (81%) of the results are accurate to within ± 0.1 of the target mix w/c ratios, 58% come to within ± 0.05 and 37% are within ± 0.025. The study shows that microscopy-based methods are more accurate and reliable compared to the BS 1881-124 physicochemical method for determining w/c ratio. The practical significance, potential sources of errors and limitations are discussed with the view to inform future applications

    Environmental risk assessments for transgenic crops producing output trait enzymes

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    The environmental risks from cultivating crops producing output trait enzymes can be rigorously assessed by testing conservative risk hypotheses of no harm to endpoints such as the abundance of wildlife, crop yield and the rate of degradation of crop residues in soil. These hypotheses can be tested with data from many sources, including evaluations of the agronomic performance and nutritional quality of the crop made during product development, and information from the scientific literature on the mode-of-action, taxonomic distribution and environmental fate of the enzyme. Few, if any, specific ecotoxicology or environmental fate studies are needed. The effective use of existing data means that regulatory decision-making, to which an environmental risk assessment provides essential information, is not unnecessarily complicated by evaluation of large amounts of new data that provide negligible improvement in the characterization of risk, and that may delay environmental benefits offered by transgenic crops containing output trait enzymes

    Cultural experience tourist motives dimensionality : a cross-cultural study

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    This empirical research of tourists&rsquo; cultural experiences aims to advance theory by developing a measurement model of tourists&rsquo; motives towards attending cultural experiences for samples of Western and Asian tourists visiting Melbourne, Australia. Drawing upon Iso-Ahola&rsquo;s (1989) seeking/avoiding dichotomy theory for tourist motivation dimensions, the hypothesized dimensions primarily included escape and seeking-related dimensions, and some hedonic dimensions because of their relevance to aesthetic products (Hirschman &amp; Holbrook, 1982; Holbrook &amp; Hirschman, 1982), which are the context for this study. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to crossvalidate the underlying dimensionality structure of cultural experience motives. A four-factor model was extracted from the EFA consistent with some theoretical formulations and was retained in the CFA. Specific cultural language group differences for the motive dimensions were also hypothesized between Western and Asian tourist samples, and within the Chinese- and Japanese-speaking Asian tourist samples, but not within the different cultural groups of English-speaking Western tourists. These cross-cultural hypotheses were tested for the motive dimension measurement model using invariance testing in CFA. The findings for the motive dimensions differing by cultural group were not as expected. Significant cultural differences between Western and Asian tourists were not found, but a new finding of this study was significant differences between English-speaking tourists in their motives for attending cultural experiences. Marketing implications of these findings are also presented.<br /

    The acute effects of a lunch containing capsaicin on energy and substrate utilisation, hormones, and satiety

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    BACKGROUND: Addition of capsaicin to the diet has been shown to increase satiety and thermogenesis. The effects of capsaicin on ghrelin, peptide YY (PYY) and glucagon-like peptide 1 (GLP-1), in relation to changes in hunger and satiety are unknown. AIM: To test the acute effects of a lunch containing capsaicin on gut derived hormones (GLP-1, ghrelin, and PYY), energy expenditure (EE), substrate oxidation and satiety at lunch in the postprandial state. METHODS: Thirty subjects (age: 31 +/- 14 years, BMI: 23.8 +/- 2.8 kg/m(2)) were studied twice in a crossover design. After 30 min resting on a bed, resting metabolic rate was measured by a ventilated hood system. Subsequently lunch (35% of daily energy intake) was served. The two lunch conditions were: (1) lunch without capsaicin and (2) lunch with capsaicin (CAPS). The macronutrient composition (energy percentage) of the lunches was 60% carbohydrates, 10% protein and 30% fat. During 3 h after the lunch diet-induced thermogenesis was measured. Furthermore, anchored 100 mm visual analogue scales on the appetite profile were collected (t = 0, 30, 60, 120, 150, 180 and 240) and blood samples were taken for analysis of GLP-1, PYY, and ghrelin concentrations (t = 0, 45, 60, 120, and 180). RESULTS: Satiety and EE were not different after CAPS lunch as compared to the control lunch. Fifteen minutes after lunch CAPS lunch increased GLP-1 (p < 0.05) and tended to decrease ghrelin (p = 0.07) as compared to the control lunch. PYY responses were not different between the CAPS lunch and the control lunch. CONCLUSIONS: An acute lunch containing capsaicin had no effect on satiety, EE, and PYY, but increased GLP-1 and tended to decrease ghrelin

    What Can Causal Networks Tell Us about Metabolic Pathways?

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    Graphical models describe the linear correlation structure of data and have been used to establish causal relationships among phenotypes in genetic mapping populations. Data are typically collected at a single point in time. Biological processes on the other hand are often non-linear and display time varying dynamics. The extent to which graphical models can recapitulate the architecture of an underlying biological processes is not well understood. We consider metabolic networks with known stoichiometry to address the fundamental question: β€œWhat can causal networks tell us about metabolic pathways?”. Using data from an Arabidopsis BaySha population and simulated data from dynamic models of pathway motifs, we assess our ability to reconstruct metabolic pathways using graphical models. Our results highlight the necessity of non-genetic residual biological variation for reliable inference. Recovery of the ordering within a pathway is possible, but should not be expected. Causal inference is sensitive to subtle patterns in the correlation structure that may be driven by a variety of factors, which may not emphasize the substrate-product relationship. We illustrate the effects of metabolic pathway architecture, epistasis and stochastic variation on correlation structure and graphical model-derived networks. We conclude that graphical models should be interpreted cautiously, especially if the implied causal relationships are to be used in the design of intervention strategies

    Revisiting the relevance of economic theory to hotel revenue management education and practice in the era of Big Data

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    Abstract This paper explores the role of economics in hospitality education and industry practice, with a particular focus on revenue management, and puts forward an argument for a return to the inclusion of economic theory in UK hospitality education, not seen since the 1990s. Given the increasing amounts of pricing data available to both managers and customers and the consequent market complexities now seen, developing economic literacy is demonstrated to be a crucial skill required for future hospitality graduates, allowing them to make successful revenue decisions and sense-check with confidence the decisions made by automated revenue systems. Economic literacy is defined as a balanced understanding of economic theory that can be applied in real-life business scenarios, extending beyond simple consideration of supply and demand to a mixture of neoclassical and behavioural approaches to economics
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