84 research outputs found

    Computational modelling and experimental tank testing of the multi float WaveSub under regular wave forcing

    Get PDF
    A submerged wave device generates energy from the relative motion of floating bodies. In WaveSub, three floats are joined to a reactor; each connected to a spring and generator. Electricity generated damps the orbital movements of the floats. The forces are non-linear and each float interacts with the others. Tuning to the wave climate is achieved by changing the line lengths, so there is a need to understand the performance trade-offs for a large number of configurations. This requires an efficient, large displacement, multidirectional, multi-body numerical scheme. Results from a 1/25 scale wave basin experiment are described. Here, we show that a time domain linear potential flow formulation (Nemoh, WEC-Sim) can match the tank testing provided that suitably tuned drag coefficients are employed. Inviscid linear potential models can match some wave device experiments; however, additional viscous terms generally provide better accuracy. Scale experiments are also prone to mechanical friction, and we estimate friction terms to improve the correlation further. The resulting error in mean power between numerical and physical models is approximately 10%. Predicted device movement shows a good match. Overall, drag terms in time domain wave energy modelling will improve simulation accuracy in wave renewable energy device design

    Computational modelling and experimental tank testing of the multi float WaveSub under regular wave forcing

    Get PDF
    A submerged wave device generates energy from the relative motion of floating bodies. In 1 WaveSub, three floats are joined to a reactor; each connected to a spring and generator. Electricity generated 2 damps the orbital movements of the floats. The forces are non-linear and each float interacts with the others. 3 Tuning to the wave climate is achieved by changing the line lengths so there is a need to understand the 4 performance trade-offs for a large number of configurations. This requires an efficient, large displacement, 5 multidirectional, multi-body numerical scheme. Results from a 1/25 scale wave basin experiment are described. 6 Here we show that a time domain linear potential flow formulation (Nemoh, WEC-Sim) can match the tank 7 testing provided that suitably tuned drag coefficients are employed. Inviscid linear potential models can match 8 some wave device experiments, however, additional viscous terms generally provide better accuracy. Scale 9 experiments are also prone to mechanical friction and we estimate friction terms to improve the correlation 10 further. The resulting error in mean power between numerical and physical models is approximately 10%. 11 Predicted device movement shows a good match. Overall, drag terms in time domain wave energy modelling 12 will improve simulation accuracy in wave renewable energy device design

    From Traditional Farming in Morocco to Early Urban Agroecology in Northern Mesopotamia: Combining Present-day Arable Weed Surveys and Crop Isotope Analysis to Reconstruct Past Agrosystems in (Semi-)arid Regions

    Get PDF
    Published by Informa UK Limited, trading as Taylor & Francis GroupWe integrate functional weed ecology with crop stable carbon and nitrogen isotope analysis to assess their combined potential for inferring arable land management practices in (semi-)arid regions from archaeobotanical assemblages. Weed and GIS survey of 60 cereal and pulse fields in Morocco are combined with crop sampling for stable isotope analysis to frame assessment of agricultural labour intensity in terms of manuring, irrigation, tillage and hand-weeding. Under low management intensity weed variation primarily reflects geographical differences, whereas under high management intensity fields in disparate regions have similar weed flora. Manured and irrigated oasis barley fields are clearly discriminated from less intensively manured rain-fed barley terraces in southern Morocco; when fields in northern and southern Morocco are considered together, climatic differences are superimposed on the agronomic intensity gradient. Barley δ13C and δ15N values clearly distinguish among the Moroccan regimes. An integrated approach combines crop isotope values with weed ecological discrimination of low- and high-intensity regimes across multiple studies (in southern Morocco and southern Europe). Analysis of archaeobotanical samples from EBA Tell Brak, Syria suggests that this early city was sustained through extensive (low-intensity, large-scale) cereal farming

    Pharmacokinetics of ibuprofen in man IV: Absorption and disposition

    Full text link
    Fifteen normal male volunters received 400, 800, and 1200 mg doses of ibuprofen as 1, 2, or 3 tablets, respectively, in crossover fashion, then 420 mg in solution form during the fourth week. Plasma concentration of ibuprofen was measured by an HPLC method. Individual subject concentration-time (C,t) data following the solution were analyzed by two different methods, and results unequivocally indicated the open two compartment model with first order absorption. However, the computer fitting of both arithmetic and geometric mean concentrations led to a different model. A method was developed to obtain absorption data (fraction of drug absorbed , F a , versus time) for a multicompartmental system from oral data alone, without intravenous data. The method assumes that V p is constant intrasubject and that absorption is complete following administration of both the solution and tablets. The method was successfully applied to the ibuprofen tablet data. It was shown also that such a method is necessary to obtain ibuprofen absorption data since intrasubject variation of the microscopic rate constants k 12 , k a21 , and k el ( as reflected by the intrasubject variation of the hybrid rate parameters λ 1 and λ 2 or Β and a) is of the same order of magnitude as intersubject variation. Absorption of ibuprofen from tablets was shown not to be simple first order as for the solution. The absorption profiles following one tablet were S- shaped, while those following 2 or 3 tablets had partial linear segments indicating zero order absorption .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45032/1/10928_2005_Article_BF01062664.pd

    Clinical impact of genomic testing in patients with suspected monogenic kidney disease

    Get PDF
    Purpose: To determine the diagnostic yield and clinical impact of exome sequencing (ES) in patients with suspected monogenic kidney disease. Methods: We performed clinically accredited singleton ES in a prospectively ascertained cohort of 204 patients assessed in multidisciplinary renal genetics clinics at four tertiary hospitals in Melbourne, Australia. Results: ES identified a molecular diagnosis in 80 (39%) patients, encompassing 35 distinct genetic disorders. Younger age at presentation was independently associated with an ES diagnosis (p < 0.001). Of those diagnosed, 31/80 (39%) had a change in their clinical diagnosis. ES diagnosis was considered to have contributed to management in 47/80 (59%), including negating the need for diagnostic renal biopsy in 10/80 (13%), changing surveillance in 35/80 (44%), and changing the treatment plan in 16/80 (20%). In cases with no change to management in the proband, the ES result had implications for the management of family members in 26/33 (79%). Cascade testing was subsequently offered to 40/80 families (50%). Conclusion: In this pragmatic pediatric and adult cohort with suspected monogenic kidney disease, ES had high diagnostic and clinical utility. Our findings, including predictors of positive diagnosis, can be used to guide clinical practice and health service design

    Beyond the ‘Tomlinson Trap’: analysing the effectiveness of section 1 of the Compensation Act 2006

    Get PDF
    One of the intentions underpinning section 1 of the Compensation Act 2006 was to provide reassurance to individual volunteers, and voluntary organisations, involved in what the provision called ‘desirable activities’ and including sport. The perception was that such volunteers, motivated by an apprehension about their increased vulnerability to negligence liability, and as driven by a fear of a wider societal compensation culture, were engaging excessively in risk-averse behaviour to the detriment of such socially desirable activities. Academic commentary on section 1 of the Compensation Act 2006 has largely regarded the provision as unnecessary and doing little more than restating existing common law practice. This article argues otherwise and, on critically reviewing the emerging jurisprudence, posits the alternative view that section 1, in practice, affords an enhanced level of protection and safeguarding for individuals undertaking functions in connection with a desirable activity. Nonetheless, the occasionally idiosyncratic judicial interpretation given to term ‘desirable activity’, potentially compounded by recent enactment of the Social Action, Responsibility and Heroism Act 2015, remains problematic. Two points of interest will be used to inform this debate. First, an analysis of the then House of Lords’ decision in Tomlinson and its celebrated ‘balancing exercise’ when assessing reasonableness in the context of negligence liability. Second, a fuller analysis of the application of section 1 in the specific context of negligence actions relating to the coaching of sport where it is argued that the, albeit limited, jurisprudence might support the practical utility of a heightened evidential threshold of gross negligence

    Sports coaching and the law of negligence: implications for coaching practice

    Get PDF
    The ordinary principles of the law of negligence are applicable in the context of sport, including claims brought against volunteer and professional coaches. Adopting the perspective of the coach, this article intends to raise awareness of the emerging intersection between the law of negligence and sports coaching, by utilising an interdisciplinary analysis designed to better safeguard and reassure coaches mindful of legal liability. Detailed scrutiny of two cases concerning alleged negligent coaching, with complementary discussion of some of the ethical dilemmas facing modern coaches, reinforces the legal duty and obligation of all coaches to adopt objectively reasonable and justifiable coaching practices when interacting with athletes. Problematically, since research suggests that some coaching practice may be underpinned by ‘entrenched legitimacy’ and ‘uncritical inertia’, it is argued that coach education and training should place a greater emphasis on developing a coach’s awareness and understanding of the evolving legal context in which they discharge the duty of care incumbent upon them

    Recent developments in protein–ligand affinity mass spectrometry

    Get PDF
    This review provides an overview of direct and indirect technologies to screen protein–ligand interactions with mass spectrometry. These technologies have as a key feature the selection or affinity purification of ligands in mixtures prior to detection. Specific fields of interest for these technologies are metabolic profiling of bioactive metabolites, natural extract screening, and the screening of libraries for bioactives, such as parallel synthesis libraries and small combichem libraries. The review addresses the principles of each of the methods discussed, with a focus on developments in recent years, and the applicability of the methods to lead generation and development in drug discovery
    • …
    corecore