5,296 research outputs found

    Beyond everyday care:exploring the experience of foster carers in holding the stories and relationships of the children in their care

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    Section A Section A presents a systematic review of the research exploring the relationship between children’s birth parents and foster carers. Fifteen studies were identified and synthesised using thematic analysis. The review highlighted power differentials between birth parents and foster carers and emphasised the importance of carers holding attitudes of compassion and understanding rather than judgement and hostility. It outlined actions which can promote positive relationships from both carers and professionals. The results are discussed in the context of existing literature and implications for clinical practice and further research are outlined. Section B Section B presents an Interpretative Phenomenological Analysis of foster carer’s experience in relating to and holding the stories of the children in their care. Ten foster carers were interviewed. Three super-ordinate themes were identified relating to the carer’s experience of processing their child’s story, holding the wider relationships surrounding children, and managing the complex dynamic between the personal role of care within the professional system. The results are discussed in the context of existing literature and recommendations for clinical practice and future research are made

    Development of freeze-thaw processing technique for disaggregation of indurated mudrocks and enhanced recovery of calcareous microfossils

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    Microfossil extraction from indurated mudrocks is widely acknowledged as challenging, especially for foraminifera. Here we report development of the freeze–thaw extraction method through the addition of rapid heating, detergent and ultrasound stages. We use indurated mudrock samples from the Toarcian (Early Jurassic) of Yorkshire, UK to assess the effectiveness and develop the freeze–thaw method. We compare our results from freeze–thaw with those from standard foraminifera processing techniques, including the use of hydrogen peroxide. Processing by freeze–thaw increased the degree of mudrock disaggregation and resulted in no damage or dissolution of foraminifera. Following the freeze–thaw method with treatment in white spirit and sodium hexametaphosphate aided the separation of foraminifera from the disaggregated clays and was twice as efficient as pressure washing. Samples processed with hydrogen peroxide contained damaged microfossils and an under representation of delicate calcareous foraminifera. Many other studies of indurated mudrocks have used hydrogen peroxide to extract foraminifera, and this might have resulted in apparently barren intervals. The freeze–thaw method outlined here provides a low-cost, low-risk and successful method of disaggregating and extracting calcareous microfossils from indurated mudrocks. We anticipate our method may be relevant for other fossil groups and merits further development

    Influence of optimized leading-edge deflection and geometric anhedral on the low-speed aerodynamic characteristics of a low-aspect-ratio highly swept arrow-wing configuration

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    An investigation conducted in the Langley 7 by 10 foot tunnel to determine the influence of an optimized leading-edge deflection on the low speed aerodynamic performance of a configuration with a low aspect ratio, highly swept wing. The sensitivity of the lateral stability derivative to geometric anhedral was also studied. The optimized leading edge deflection was developed by aligning the leading edge with the incoming flow along the entire span. Owing to spanwise variation of unwash, the resulting optimized leading edge was a smooth, continuously warped surface for which the deflection varied from 16 deg at the side of body to 50 deg at the wing tip. For the particular configuration studied, levels of leading-edge suction on the order of 90 percent were achieved. The results of tests conducted to determine the sensitivity of the lateral stability derivative to geometric anhedral indicate values which are in reasonable agreement with estimates provided by simple vortex-lattice theories

    Effects of wing leading-edge deflection on low-speed aerodynamic characteristics of a low-aspect-ratio highly swept arrow-wing configuration

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    Static force tests were conducted in the Langley V/STOL tunnel at a Reynolds number (based on the mean aerodynamic chord) of about 2.0 x 10 to the 6th power for an angle-of-attack range from about - 10 deg to 17 deg and angles of sideslip of 0 and + or - 5 deg. Limited flow visualization studies were also conducted in order to provide a qualitative assessment of leading-edge upwash characteristics

    Results of recent NASA research on low-speed aerodynamic characteristics of supersonic cruise aircraft

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    The relatively low values of lift-curve slope produced by highly swept arrow wings, coupled with the low scrape angle of the fuselage, resulted in relatively low values of take-off and approach lift coefficients. Through the use of more efficient high-lift systems and the application of propulsive-lift concepts, it is possible to optimize the engine-airframe design for maximum range potential and also to provide good low-speed performance. Nose strakes provide significant improvements in directional stability characteristics and the use of a propulsive lateral control system provides a solution to problems associated with inherently low levels of lateral control

    A major outburst from the X-ray binary RX J0520.5-6932

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    We report on the analysis of 8 years of MAssive Compact Halo Objects (MACHO) data for the source RX J0520.5-6932. A regular period of 24.4 days has been confirmed, however this is manifest almost entirely in the red part of the spectrum. A major outburst, lasting approximately 200 days, was observed which increased the apparent brightness of the object by approximately 0.15 magnitudes without significantly altering its V-R colour index. This outburst was also seen in X-ray data. The evidence from this analysis points to the identification of this object as a Be/X-ray binary with a periodically variable circumstellar disk and a very early optical counterpart.Comment: Paper has been accepted by MNRA

    Distributed upper-surface blowing concept

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    A low speed investigation was conducted in the Langley V/STOL tunnel to determine the powered lift aerodynamic performance of a distributed upper surface blown propulsive lift transport model. The model used blowing slots across the span of the wing to produce a thin jet efflux near the leading edge and at the knee of the trailing edge flap (internally blown jet flap). Results indicate that these concepts have both good propulsive related lift and low drag due to lift characteristics because of uniform spanwise propulsive thrust. The leading edge blowing concept provides low speed lift characteristics which are competitive with the flap-hinge-line blowing concept and does not require additional leading edge treatment for prevention of abrupt stall

    Low-speed aerodynamic characteristics of a highly swept, untwisted uncambered arrow wing

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    An investigation was conducted in the Langley 4- by 7-Meter Tunnel to provide a detailed study of wing pressure distributions and forces and moments acting on a highly swept arrow-wing model at low Mach numbers (0.25). A limited investigation of the effect of spoilers at several locations was also conducted. Analysis of the pressure data shows that for the configuration with undeflected leading edges, vortex separation occurs on the outboard wing panel for angles of attack on the order of only 3 deg, whereas conventional leading-edge separation occurs at a nondimensional semispan station of 0.654 for the same incidence angle. The pressure data further show that vortex separation exists at wing stations more inboard for angles of attack on the order of 7 deg and that these vortices move inboard and forward with increasing angle of attack. The force and moment data show the expected nonlinear increments in lift and pitching moment and the increased drag associated with the vortex separation. The pressure data and corresponding force and moment data confirm that deflecting the entire wing leading edge uniformly to 30 deg is effective in forestalling the onset of flow separation to angles of attack greater than 8.6 deg; however, the inboard portion of the leading edge is overdeflected. The investigation further identifies the contribution of the trailing-edge flap deflection to the leading-edge upwash fields

    Vocal mimicry in the spotted bowerbird Chlamydera maculata

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