647 research outputs found

    A Survey of Plasmas and Their Applications

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    Plasmas are everywhere and relevant to everyone. We bath in a sea of photons, quanta of electromagnetic radiation, whose sources (natural and artificial) are dominantly plasma-based (stars, fluorescent lights, arc lamps.. .). Plasma surface modification and materials processing contribute increasingly to a wide array of modern artifacts; e.g., tiny plasma discharge elements constitute the pixel arrays of plasma televisions and plasma processing provides roughly one-third of the steps to produce semiconductors, essential elements of our networking and computing infrastructure. Finally, plasmas are central to many cutting edge technologies with high potential (compact high-energy particle accelerators; plasma-enhanced waste processors; high tolerance surface preparation and multifuel preprocessors for transportation systems; fusion for energy production)

    The influence of school and teaching quality on children’s progress in primary school

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    This report investigates the way school and classroom processes affect the cognitive progress and social/behavioural development of children between the ages of 6 (Year 1) and 10 (Year 5) in primary schools in England. The research is part of the larger longitudinal study of Effective Pre-School and Primary Education (EPPE 3-11) funded by the Department for Children, Schools and Families (DCSF) that is following children’s cognitive and social/behavioural development from ages 3 to 11 years. The EPPE 3-11 study investigates both pre-school and primary school influences on children’s attainment, progress and social/behavioural development. This report describes the results of quantitative analyses based on a subsample of 1160 EPPE children across Year 1 to 5 of primary education. The research builds on the earlier analyses of children’s Reading and Mathematics attainments and social/behavioural outcomes in Year 5 for the full EPPE 3-11 sample (see Sammons, 2007a; 2007b), by investigating relationships between children’s outcomes and measures of classroom processes, collected through direct observation of Year 5 classes in 125 focal schools chosen from the larger EPPE 3-11 data set. The analyses also explore patterns of association between children’s outcomes and broader measures of overall school characteristics derived from teacher questionnaires and Ofsted inspection reports for this sub-sample of schools

    Relationships between pupils’ self-perceptions, views of primary school and their development in Year 5

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    The Effective Pre-school and Primary Education Project 3-11 (EPPE 3-11) is a largescale longitudinal study of the impact of pre-school and primary school on children’s developmental outcomes, both cognitive and social/behavioural. The study has been following children from the start of pre-school (at age 3 years plus) through to the end of primary school. Previous reports have focused on the educational and social/behavioural outcomes of the EPPE 3-11 sample at the end of Year 5 (age 10) and progress from the end of Year 1 (age 6) to the end of Year 5 (age 10) in primary school (Sammons et al., 2007a; 2007b). The research also explored the predictive power of a wide variety of child, parent, and family characteristics on attainment and development, including the Early years home learning environment (HLE) during the years of preschool and aspects of the later HLE during Key stage 1 of primary school (Sammons et al., 2002; 2003; Sylva et al., 2004). This research builds on earlier reports (Sammons et al., 2007a; 2007b) by investigating relationships between children’s outcomes in Year 5 and aspects of pupils’ selfperceptions and their views of primary school, measured in Year 5 (age 10) and in Year 2 (age 7) of primary school, controlling for background characteristics. These measures have been derived from a self-report instrument completed by EPPE 3-11 children. The analyses explored associations between children’s progress and development over time and their self-perceptions and views of primary school

    Pupils' self-perceptions and views of primary school in year 5

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    The Effective Pre-School and Primary Education 3-11 (EPPE 3-11) project investigates the impact of preschool, primary school and family on a range of outcomes for a national sample of approximately 2,800 children in England between the ages of 3 and 11 years. This Research Brief presents findings on pupils’ Self-perceptions (‘Enjoyment of school’, ‘Anxiety and Isolation’, ‘Academic self-image’ and ‘Behavioural self-image’) and their views of different features of primary school (‘Teachers’ support for pupils’ learning’, ‘Headteacher qualities’ and ‘Positive social environment’) in Year 5. The analyses involved two steps: first, differences in pupils’ Self-perceptions and Views of primary school measured at Year 5 were explored, in relation to child, family and Home Learning Environment (HLE) characteristics. Second, the relationships between pupils’ Self-perceptions and their Views of primary school and educational outcomes and progress, both cognitive (Reading and Mathematics) and social/behavioural (‘Self-regulation’, ‘Hyperactivity’, ‘Pro-social’ and ‘Anti-social’ behaviour) were investigated. The analyses also explored pupils’ Self-perceptions measured at a younger age (Year 2) and how they relate to children’s later cognitive and social/behavioural outcomes in Year 5 and progress from Year 1 to Year 5

    Effiziente ZwischenfrĂŒchte zur Rekultivierung landwirtschaftlicher FlĂ€chen beim Bau einer 380 KV Höchstspannungs-Erdkabelleitung in der westfĂ€lischen Tieflandsbucht

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    In der westfĂ€lischen Tieflandsbucht wurden zwei parallele KabelgrĂ€ben mit je 5,5 m Sohlbreite errichtet, die 4 Gigawatt Stromleistung ĂŒbertragen. Das Bauverfahren der Erdkabeltrasse verursacht eine enorme Störung des Bodens aller physikalischen, chemischen und biologischen Bodenkennwerte. Der Naturraum, indem die 3,5 km lange Erdkabelleitung verlĂ€uft, wird intensiv, landwirtschaftlich genutzt und zeichnet sich bodenkundlich durch eine ausgeprĂ€gte HeterogenitĂ€t aus. Mithilfe eines speziellen Konzeptes sollen die Böden ĂŒber der Kabeltrasse rekultiviert an die Landwirte ĂŒbergeben werden. Zur ÜberprĂŒfung der Rekultivierungsleistung unterschiedlicher Zwischenfruchtkulturen sowie deren Mischungen wurden Parzellen auf einem TeilstĂŒck der Kabeltrasse in einem Langzeitversuch angelegt. Erste Versuchsergebnisse zeigen eine Differenzierung der verschiedenen Kulturen/Mischungen in Hinblick auf das Rekultivierungspotential

    Interaction of Dendritic Cells with Skin Endothelium: A New Perspective on Immunosurveillance

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    The goal of this study was to determine the mechanisms by which dendritic cells (DCs) in blood could interact with endothelium, a prerequisite to extravasation into tissues. Our results indicate that DCs express both HECA-452–reactive and nonreactive isoforms of P-selectin glycoprotein ligand 1 (PSGL-1) and can tether and roll efficiently on E- and P-selectin under flow conditions in vitro. Freshly isolated blood DCs were further observed to roll continuously along noninflamed murine dermal endothelium in vivo. This interaction is strictly dependent on endothelial selectins, as shown by experiments with blocking antibodies and with E- and P-selectin–deficient mice. We hypothesize that DCs in blood are constitutively poised at the interface of blood and skin, ready to extravasate upon induction of inflammation, and we showed that cutaneous inflammation results in a rapid recruitment of DCs from the blood to tissues. We propose that this is an important and previously unappreciated element of immunosurveillance
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