76 research outputs found

    Educational aspirations in inner city schools

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    The research aimed to assess the nature and level of pupils’ educational aspirations and to elucidate the factors that influence these aspirations. A sample of five inner city comprehensive secondary schools were selected by their Local Authority because of poor pupil attendance, below average examination results and low rates of continuing in full-time education after the age of 16. Schools were all ethnically mixed and co-educational. Over 800 pupils aged 12-14 completed a questionnaire assessing pupils’ experience of home, school and their peers. A sub-sample of 48 pupils selected by teachers to reflect ethnicity and ability levels in individual schools also participated in detailed focus group interviews. There were no significant differences in aspirations by gender or year group, but differences between ethnic groups were marked. Black African, Asian Other and Pakistani groups had significantly higher educational aspirations than the White British group, who had the lowest aspirations. The results suggest the high aspirations of Black African, Asian Other and Pakistani pupils are mediated through strong academic self-concept, positive peer support, a commitment to schooling and high educational aspirations in the home. They also suggest that low educational aspirations may have different mediating influences in different ethnic groups. The low aspirations of White British pupils seem to relate most strongly to poor academic self-concept and low educational aspirations in the home, while for Black Caribbean pupils disaffection, negative peers and low commitment to schooling appear more relevant. Interviews with pupils corroborated the above findings and further illuminated the factors students described as important in their educational aspirations. The results are discussed in relation to theories of aspiration which stress its nature as a cultural capacity

    Mirror coating solution for the cryogenic Einstein telescope

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    Planned, cryogenic gravitational-wave detectors will require improved coatings with a strain thermal noise reduced by a factor of 25 compared to Advanced LIGO. In this article, we present investigations of HfO2 doped with SiO2 as a new coating material for future detectors. Our measurements show an extinction coefficient of k=6×10−6 and a mechanical loss of ϕ=3.8×10−4 at 10,K, which is a factor of 2 below that of SiO2, the currently used low refractive-index coating material. These properties make HfO2 doped with SiO2 ideally suited as a low-index partner material for use with a-Si in the lower part of a multimaterial coating. Based on these results we present a multimaterial coating design which, for the first time, can simultaneously meet the strict requirements on optical absorption and thermal noise of the cryogenic Einstein Telescope

    Genetic Engineering in Streptomyces roseosporus to Produce Hybrid Lipopeptide Antibiotics

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    SummaryDaptomycin is a lipopeptide antibiotic produced by a nonribosomal peptide synthetase (NRPS) in Streptomyces roseosporus. The holoenzyme is composed of three subunits, encoded by the dptA, dptBC, and dptD genes, each responsible for incorporating particular amino acids into the peptide. We introduced expression plasmids carrying dptD or NRPS genes encoding subunits from two related lipopeptide biosynthetic pathways into a daptomycin nonproducing strain of S. roseosporus harboring a deletion of dptD. All constructs successfully complemented the deletion in trans, generating three peptide cores related to daptomycin. When these were coupled with incomplete methylation of 1 amino acid and natural variation in the lipid side chain, 18 lipopeptides were generated. Substantial amounts of nine of these compounds were readily obtained by fermentation, and all displayed antibacterial activity against gram-positive pathogens

    Mechanical loss of laser-welded fused silica fibers

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    The mechanical quality factor of a carbon dioxide laser-welded fiber was measured and compared to flame-welded fibers to determine the suitability of laser welding for attaching suspension fibers to test masses in precision experiments. The loss in the fiber was found to be limited primarily by thermoelastic damping and surface loss, rather than loss from the weld. This technique is attractive for the attachment of fused silica suspensions where low thermal noise and precision location of the weld are considered. © 2006 American Institute of Physics.Gregory Harry, Thomas Corbitt, Marat Freytsis, David Ottaway, and Nergis Mavalval

    Mechanical loss of laser-welded fused silica fibers

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    The mechanical quality factor of a carbon dioxide laser-welded fiber was measured and compared to flame-welded fibers to determine the suitability of laser welding for attaching suspension fibers to test masses in precision experiments. The loss in the fiber was found to be limited primarily by thermoelastic damping and surface loss, rather than loss from the weld. This technique is attractive for the attachment of fused silica suspensions where low thermal noise and precision location of the weld are considered. © 2006 American Institute of Physics.Gregory Harry, Thomas Corbitt, Marat Freytsis, David Ottaway, and Nergis Mavalval

    The virtual construction site: a decision support system for construction planning (VIRCON)

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    The pregnant man: race, difference and subjectivity in Alan Paton’s Kalahari writing

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    In South African imaginative writing and scholarly research, there is currently an extensive and wide-ranging interest in the ‘Bushman’, either as a tragic figure of colonial history, as a contested site of misrepresentation, or even as an exemplary model of environmental consciousness. Writing and research about ‘Bushmen’ has not only become pervasive in the academy, but also a site of controversy and theoretical contestation. It is in this context that this paper investigates the meaning and significance of ‘Bushmen’ for Alan Paton, one of South Africa’s most well-known writers. Paton’s writing is not usually associated with ‘Bushman’ studies, yet this article shows that the ‘Bushman’ became a highly charged and ambivalent figure in his imagination. Paton’s problematic ideas are contextualised more carefully by looking at the broader context of South African letters. The article initially analyses Paton’s representation of ‘Bushmen’ in his Lost City of the Kalahari travel narrative (1956, published in 2005. Pietermaritzburg: KZN Press), and also discusses unpublished archival photographs. A study of the figure of the ‘Bushman’ throughout the entire corpus of his writing, ranging from early journalism to late autobiography, allows us to trace the shift of his views, enabling us to reflect not only on Paton’s thinking about racial otherness, but also gauge the extent to which his encounter with the Kalahari Bushmen destabilised his sense of self, finally also preventing the publication of the travelogueDepartment of HE and Training approved lis

    Cost-effectiveness of Out-of-Hospital Continuous Positive Airway Pressure for Acute Respiratory Failure

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    Study objective: We determine the cost-effectiveness of out-of-hospital continuous positive airway pressure (CPAP) compared with standard care for adults presenting to emergency medical services with acute respiratory failure. Methods: We developed an economic model using a United Kingdom health care system perspective to compare the costs and health outcomes of out-of-hospital CPAP to standard care (inhospital noninvasive ventilation) when applied to a hypothetical cohort of patients with acute respiratory failure. The model assigned each patient a probability of intubation or death, depending on the patient's characteristics and whether he or she had out-of-hospital CPAP or standard care. The patients who survived accrued lifetime quality-adjusted life-years (QALYs) and health care costs according to their age and sex. Costs were accrued through intervention and hospital treatment costs, which depended on patient outcomes. All results were converted into US dollars, using the Organisation for Economic Co-operation and Development purchasing power parities rates. Results: Out-of-hospital CPAP was more effective than standard care but was also more expensive, with an incremental cost-effectiveness ratio of £20,514 per QALY (29,720/QALY)anda49.529,720/QALY) and a 49.5% probability of being cost-effective at the £20,000 per QALY (29,000/QALY) threshold. The probability of out-of-hospital CPAP's being cost-effective at the £20,000 per QALY ($29,000/QALY) threshold depended on the incidence of eligible patients and varied from 35.4% when a low estimate of incidence was used to 93.8% with a high estimate. Variation in the incidence of eligible patients also had a marked influence on the expected value of sample information for a future randomized trial. Conclusion: The cost-effectiveness of out-of-hospital CPAP is uncertain. The incidence of patients eligible for out-of-hospital CPAP appears to be the key determinant of cost-effectiveness
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