1,742 research outputs found

    Topology of the Galaxy Distribution in the Hubble Deep Fields

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    We have studied topology of the distribution of the high redshift galaxies identified in the Hubble Deep Field (HDF) North and South. The two-dimensional genus is measured from the projected distributions of the HDF galaxies at angular scales from 3.83.8'' to 6.1 6.1''. We have also divided the samples into three redshift slices with roughly equal number of galaxies using photometric redshifts to see possible evolutionary effects on the topology. The genus curve of the HDF North clearly indicates clustering of galaxies over the Poisson distribution while the clustering is somewhat weaker in the HDF South. This clustering is mainly due to the nearer galaxies in the samples. We have also found that the genus curve of galaxies in the HDF is consistent with the Gaussian random phase distribution with no significant redshift dependence.Comment: 14 pages, 4 figures, submitted to Ap

    Formality and informality in the summative assessment of motor vehicle apprentices: a case study

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    This article explores the interaction of formal and informal attributes of competence‐based assessment. Specifically, it presents evidence from a small qualitative case study of summative assessment practices for competence‐based qualifications within apprenticeships in the motor industry in England. The data are analysed through applying an adaptation of a framework for exploring the interplay of formality and informality in learning. This analysis reveals informal mentoring as a significant element which influences not only the process of assessment, but also its outcomes. We offer different possible interpretations of the data and their analysis, and conclude that, whichever interpretation is adopted, there appears to be a need for greater capacity‐building for assessors at a local level. This could acknowledge a more holistic role for assessors; recognise the importance of assessors’ informal practices in the formal retention and achievement of apprentices; and enhance awareness of inequalities that may be reinforced by both informal and formal attributes of assessment practices

    Collaboration and contestation in further and higher education partnerships in England: a Bourdieusian field analysis

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    Internationally, ‘College for All’ policies are creating new forms of vocational higher education (HE), and shifting relationships between HE and further education (FE) institutions. In this paper, we consider the way in which this is being implemented in England, drawing on a detailed qualitative case study of a regional HE–FE partnership to widen participation. We focus on the complex mix of collaboration and contestation that arose within it, and how these affected socially differentiated groups of students following high- and low-status routes through its provision. We outline Bourdieu’s concept of ‘field’ as a framework for our analysis and interpretation, including its theoretical ambiguities regarding the definition and scale of fields. Through hermeneutic dialogue between data and theory, we tentatively suggest that such partnerships represent bridges between HE and FE. These bridges are strong between higher-status institutions, but highly contested between lower-status institutions competing closely for distinction. We conclude that the trajectories and outcomes for socially disadvantaged students require attention and collective action to address the inequalities they face, and that our theoretical approach may have wider international relevance beyond the English case

    Challenges to enabling and implementing Natural Flood Management in Scotland

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    The research for this paper was supported by the Scottish Government RESAS Strategic Research Programme 2011–2016.We explore factors that constrain implementation of Natural Flood Management (NFM), based on qualitative analysis of interviews with those influencing and enabling flood risk management in Scotland. NFM entails collaboration by multiple individuals and organisations to plan and deliver measures such as re-meandering or buffer strips. Our interviewees identified many interacting issues. They particularly focused on difficulties in securing resources, and evidence gaps and uncertainties associated with NFM. Co-ordination was not simple, often requiring new types of skill, expertise, and resources. NFM is thus outside the ‘comfort zone’ of many leading or engaged with flood risk management. These experiences echo and elaborate on other studies of attempts to encourage sustainable flood management. To tackle these challenges, practitioners should reflect how pre-existing ideas and practices may shape and constrain new approaches to managing floods, while research is needed on specific strategies that can assist in enabling change.Publisher PDFPeer reviewe

    Human schistosomiasis

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    Human schistosomiasis-or bilharzia-is a parasitic disease caused by trematode fl ukes of the genus Schistosoma. By conservative estimates, at least 230 million people worldwide are infected with Schistosoma spp. Adult schistosome worms colonise human blood vessels for years, successfully evading the immune system while excreting hundreds to thousands of eggs daily, which must either leave the body in excreta or become trapped in nearby tissues. Trapped eggs induce a distinct immune-mediated granulomatous response that causes local and systemic pathological eff ects ranging from anaemia, growth stunting, impaired cognition, and decreased physical fi tness, to organ-specifi c eff ects such as severe hepatosplenism, periportal fi brosis with portal hypertension, and urogenital infl ammation and scarring. At present, preventive public health measures in endemic regions consist of treatment once every 1 or 2 years with the isoquinolinone drug, praziquantel, to suppress morbidity. In some locations, elimination of transmission is now the goal; however, more sensitive diagnostics are needed in both the fi eld and clinics, and integrated environmental and health-care management will be needed to ensure elimination. © Chataway et al. Open Access article distributed under the terms of CC BY

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    Study and implementation of urogenital schistosomiasis elimination in Zanzibar (Unguja and Pemba islands) using an integrated multidisciplinary approach

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    ABSTRACT: BACKGROUND: Schistosomiasis is a parasitic infection that continues to be a major public health problem in many developing countries being responsible for an estimated burden of at least 1.4 million disability-adjusted life years (DALYs) in Africa alone. However, morbidity due to schistosomiasis has been greatly reduced in some parts of the world, including Zanzibar. The Zanzibar government is now committed to eliminate urogenital schistosomiasis. Over the next 3--5 years, the whole at-risk population will be administered praziquantel (40 mg/kg) biannually. Additionally, snail control and behaviour change interventions will be implemented in selected communities and the impact measured in a randomized intervention trial. METHODS: In this 5-year research study, on both Unguja and Pemba islands, urogenital schistosomiasis will be assessed in 45 communities with urine filtration and reagent strips in 4,500 schoolchildren aged 9--12 years annually, and in 4,500 first-year schoolchildren and 2,250 adults in years 1 and 5. Additionally, from first-year schoolchildren, a finger-prick blood sample will be collected and examined for Schistosoma haematobium infection biomarkers. Changes in prevalence and infection intensity will be assessed annually. Among the 45 communities, 15 were randomized for biannual snail control with niclosamide, in concordance with preventive chemotherapy campaigns. The reduction of Bulinus globosus snail populations and S. haematobium-infected snails will be investigated. In 15 other communities, interventions triggering behaviour change have been designed and will be implemented in collaboration with the community. A change in knowledge, attitudes and practices will be assessed annually through focus group discussions and in-depth interviews with schoolchildren, teachers, parents and community leaders. In all 45 communities, changes in the health system, water and sanitation infrastructure will be annually tracked by standardized questionnaire-interviews with community leaders. Additional issues potentially impacting on study outcomes and all incurring costs will be monitored and recorded. DISCUSSION: Elimination of schistosomiasis has become a priority on the agenda of the Zanzibar government and the international community. Our study will contribute to identifying what, in addition to preventive chemotherapy, needs to be done to prevent, control, and ultimately eliminate schistosomiasis, and to draw lessons for current and future schistosomiasis elimination programmes in Africa and elsewhere.Trial registrationISRCTN4883768
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