1,654 research outputs found

    Quantitative Assessment of Deformation-Induced Damage in a Semisolid Aluminum Alloy via X-ray Microtomography

    Get PDF
    Semisolid tensile testing combined with X-ray microtomography (XMT) was used to characterize the development of internal damage as a function of strain in an aluminum-magnesium alloy, AA5182. Novel techniques were developed to allow the quantification of both the size evolution and orientation of the damage to determine mechanisms controlling the early stage growth and localization. During the initial stages of semisolid deformation, it was observed that strain was accommodated by both the growth of as-cast porosity and the detection of new damage-based voids. As the volume fraction of damage increases, the growth of voids occurs in an orientation perpendicular to the loading direction, both through expansion within the grain boundary liquid and void coalescence. The damage then localizes, causing failur

    Knowledge Wars: Professionalisation, Organisational Justice and Competing Knowledge Paradigms in British Policing

    Get PDF
    The professionalisation agenda in British policing is being driven by the College of Policing. Whilst there are a number of definitions of professionalism (Sklansky, 2014), the basic tenets of a professional organisation are that the employees follow a code of ethics, there is a commitment to use expert knowledge and that there is an element of self-regulation. Within the professionalisation agenda for the British police there are a number of strands. These include the implementation of a police code of ethics, the development of a police education qualification framework (PEQF) and wide support of police and academic collaborations to ensure police practice becomes increasingly evidence based. This chapter focuses on the latter strand of work, evidence based policing (EBP), particularly as there has been extensive debate in both the academic and policing fields about the extent to which police officers are both supportive and understanding of this concept and the extent to which they feel involved in EBP at all stages of the process (Fleming and Wingrove, 2017). In doing so, the chapter will seek to explore some of the potential issues which arise in respect of EBP by using the theory and principles of organisational justice. This will be used to explore the changing conceptualisation of knowledge within police organisations and the link this has with the professionalisation of policing. We will attempt to do this firstly, by exploring the concept and principles of organisational justice and applying this to the context of policing, EBP and knowledge work. Secondly, we will explore what we mean by knowledge in a police context and, thirdly, we will examine the potential to apply the concept of organisational justice to current views on the constitution of knowledge and knowledge outputs in the modern policing milie

    Assessment of resource availability and sustainability for subsistence fishers in South Africa, with a review of resource management procedures

    Get PDF
    The availability of resources and their suitability for subsistence and small-scale commercial fishers in South Africa were assessed and appropriate options for the management of resources recommended. Assessment of current resource utilization and recommendations for future subsistence and/or small-scale commercial use were based on information gathered during a nationwide survey of 144 subsistence fishing communities in South Africa and a review of relevant published and unpublished literature. Current patterns of resource use in three regions of the coast (West, South and East coasts) revealed that most true subsistence fisheries occur in the eastern half of the country. These fisheries are primarily focused on invertebrate species found on intertidal rocky shores and sandy beaches, or in estuaries. Fish are harvested by rod or handline, netting or traditional fishing methods (fishtraps, spearing, baited baskets). No “new” or previously underutilized resources were identified as suitable for subsistence fishing in any of the three regions. The potential for several new small-scale commercial fisheries was identified, but the need to retain certain resources for subsistence fisheries (rather than converting them to small-scale commercial fisheries) was evident in certain areas. Resources with high commercial value were not considered suitable for subsistence fishing, but rather for the introduction of small-scale commercial fisheries. The overall management strategy for the subsistence sector, which is currently in the process of being developed, must ensure sufficient flexibility to be able to take into account regional and site-specific requirements. It will also need to develop co-management structures, protect traditional fishing practices, avoid user conflict and provide for no-take areas, all within the framework of sustainable resource utilization.Keywords: estuarine resources, fisheries management, intertidal resources, subsistence fisheries, subtidal resourcesAfrican Journal of Marine Science 2002, 24: 489–50

    Role of Leukotriene Receptor Antagonists in the Treatment of Exercise-Induced Bronchoconstriction: A Review

    Get PDF
    Asthma is a very common disorder that still causes significant morbidity and mortality. A high percentage of individuals with asthma also experience exercise-induced bronchoconstriction (EIB). This article reviews the current literature and updates the reader on the safety, efficacy, and clinical applications of leukotriene modifiers in the treatment of EIB

    Revisiting the need for a literature search narrative: A brief methodological note

    Get PDF
    This is the author accepted manuscript. The final version is available from Wiley via the DOI inthis recordIn this method note, we question if the primary search strategy in a systematic review should be accompanied by a search narrative. A search narrative could offer a conceptual and contextual report on the search strategy, which we suggest might benefit the peer review of literature searches and increase engagement with, and discussion of, the literature search strategy from review stakeholders, topic experts, and lay users of research. Search narratives would also increase the transparency of decision-making in literature searching.Centre for Outcomes Research and Effectiveness (CORE)National Institute for Health Research (NIHR)Cochrane Common Mental Disorders (CCMD) Grou

    The EPICure study: association between hemodynamics and lung function at 11 years after extremely preterm birth.

    Get PDF
    To investigate the relationship between disturbed lung function and large-artery hemodynamics in school-age children born extremely preterm (EP) (at 25 completed weeks of gestation or less)

    Does pulmonary rehabilitation address cardiovascular risk factors in patients with COPD?

    Get PDF
    Background Patients with COPD have an increased risk of cardiovascular disease. Whilst pulmonary rehabilitation has proven benefit for exercise tolerance and quality of life, any effect on cardiovascular risk has not been fully investigated. We hypothesised that pulmonary rehabilitation, through the exercise and nutritional intervention, would address these factors. Methods Thirty-two stable patients with COPD commenced rehabilitation, and were compared with 20 age and gender matched controls at baseline assessment. In all subjects, aortic pulse wave velocity (PWV) an independent non-invasive predictor of cardiovascular risk, blood pressure (BP), interleukin-6 (IL-6) and fasting glucose and lipids were determined. These measures, and the incremental shuttle walk test (ISWT) were repeated in the patients who completed pulmonary rehabilitation. Results On commencement of rehabilitation aortic PWV was increased in patients compared with controls (p < 0.05), despite mean BP, age and gender being similar. The IL-6 was also increased (p < 0.05). Twenty-two patients completed study assessments. In these subjects, rehabilitation reduced mean (SD) aortic PWV (9.8 (3.0) to 9.3 (2.7) m/s (p < 0.05)), and systolic and diastolic BP by 10 mmHg and 5 mmHg respectively (p < 0.01). Total cholesterol and ISWT also improved (p < 0.05). On linear regression analysis, the reduction in aortic PWV was attributed to reducing the BP. Conclusion Cardiovascular risk factors including blood pressure and thereby aortic stiffness were improved following a course of standard multidisciplinary pulmonary rehabilitation in patients with COPD

    Further Definition of the Mass-Metallicity Relation in Globular Cluster Systems Around Brightest Cluster Galaxies

    Full text link
    We combine the globular cluster data for fifteen Brightest Cluster Galaxies and use this material to trace the mass-metallicity relations (MMR) in their globular cluster systems (GCSs). This work extends previous studies which correlate the properties of the MMR with those of the host galaxy. Our combined data sets show a mean trend for the metal-poor (MP) subpopulation which corresponds to a scaling of heavy-element abundance with cluster mass Z ~ M^(0.30+/-0.05). No trend is seen for the metal-rich (MR) subpopulation which has a scaling relation that is consistent with zero. We also find that the scaling exponent is independent of the GCS specific frequency and host galaxy luminosity, except perhaps for dwarf galaxies. We present new photometry in (g',i') obtained with Gemini/GMOS for the globular cluster populations around the southern giant ellipticals NGC 5193 and IC 4329. Both galaxies have rich cluster populations which show up as normal, bimodal sequences in the colour-magnitude diagram. We test the observed MMRs and argue that they are statistically real, and not an artifact caused by the method we used. We also argue against asymmetric contamination causing the observed MMR as our mean results are no different from other contamination-free studies. Finally, we compare our method to the standard bimodal fitting method (KMM or RMIX) and find our results are consistent. Interpretation of these results is consistent with recent models for globular cluster formation in which the MMR is determined by GC self-enrichment during their brief formation period.Comment: 35 pages, 20 figures. Accepted by Astronomical Journal. Complete preprint including high resolution figures available at http://www.physics.mcmaster.ca/~cockcroft/MMRpape
    • …
    corecore