2,240 research outputs found

    Predicted and hot-film measured Tollmien-Schlichting wave characteristics

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    The Tollmien-Schlichting (TS) instability is a time-dependence instability which can lead to transition of laminar boundary layers on airfoils. A comparison of theoretical predictions and experimental observations of the TS instability on the NLF(1)-0414F airfoil designed by Viken and Pfenninger. The theoretical predictions were obtained using the SALLY stability code. Test results, from the same hot films that were used to detect transition, revealed that TS waves could be detected by the hot films if the hot-film signal was adequately modified

    Design and experimental evaluation of a swept supercritical Laminar Flow Control (LFC) airfoil

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    A large chord swept supercritical laminar flow control (LFC) airfoil was designed, constructed, and tested in the NASA Langley 8-ft Transonic Pressure Tunnel (TPT). The LFC airfoil experiment was established to provide basic information concerning the design and compatibility of high-performance supercritical airfoils with suction boundary layer control achieved through discrete fine slots or porous surface concepts. It was aimed at validating prediction techniques and establishing a technology base for future transport designs and drag reduction. Good agreement was obtained between measured and theoretically designed shockless pressure distributions. Suction laminarization was maintained over an extensive supercritical zone up to high Reynolds numbers before transition gradually moved forward. Full-chord laminar flow was maintained on the upper and lower surfaces at M sub infinity = 0.82 up to R sub c is less than or equal to 12 x 10 to the 6th power. When accounting for both the suction and wake drag, the total drag could be reducted by at least one-half of that for an equivalent turbulent airfoil. Specific objectives for the LFC experiment are given

    The Attitudes about Complex Therapy Scale (ACTS) in Type 2 Diabetes and Cardiovascular Disease: Development, Validity and Reliability

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    Background: Type 2 diabetes is associated with cardiovascular disease, and patients with both conditions are prescribed complex medication regimens. Aim: The aim was to develop a reliable and valid measure of attitudes associated with the prescription and management of multiple medicines in patients with Type 2 diabetes and cardiovascular disease. Methods: Principal component analysis (PCA) and Cronbach alpha assessed the reliability of the Attitudes about Complex Therapy Scale (ACTS). Examinations of relationships with related measures inform concurrent validity. Questionnaires were sent to a cross-sectional sample of 480 people prescribed multiple medicines for co-morbid Type 2 diabetes. Results: Cronbach alpha was 0.76, indicating the scale had good internal reliability. PCA rotated a four factor model accounting for 37% of the variance. Four subscales identified; 1. Concerns about multiple medicines and increasing numbers of medicines; 2.Anxiety over missed medicines; 3. Desires to substitute medicines and reduce the number of medicines prescribed and; 4. Perceptions related to organising and managing complex therapy. The ACTS showed significant relationships with measures of anxiety, depression, general beliefs about medicines and self-efficacy. Also, the ACTS significantly correlated with adherence to medicines, showing good predictive validity. Conclusion: The ACTS was designed to assess negative attitudes towards complex therapy and multiple medication management. This tool could aid prescribing decisions and may identify people who are intentionally non-adherent to all or some of their medicines

    String Tension from Monopoles in SU(2) Lattice Gauge Theory

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    The axis for Figure 2 was wrong. It has been fixed and the postscript file replaced (The file was called comp.ps).Comment: (22 pages latex (revtex); 2 figures appended as postscript files - search for mono.ps and comp.ps. Figures mailed on request--send a note to [email protected]) Preprint ILL-(TH)-94-#1

    Large Loops of Magnetic Current and Confinement in Four Dimensional U(1)U(1) Lattice Gauge Theory

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    We calculate the heavy quark potential from the magnetic current due to monopoles in four dimensional U(1)U(1) lattice gauge theory. The magnetic current is found from link angle configurations using the DeGrand-Toussaint identification method. The link angle configurations are generated in a cosine action simulation on a 24424^4 lattice. The magnetic current is resolved into large loops which wrap around the lattice and simple loops which do not. Wrapping loops are found only in the confined phase. It is shown that the long range part of the heavy quark potential, in particular the string tension, can be calculated solely from the large, wrapping loops of magnetic current.Comment: 15 pages (Latex file plus 3 postscript files appended), Univeristy of Illinois Preprint ILL-(TH)-93-\#1

    Representations of sport in the revolutionary socialist press in Britain, 1988–2012

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    This paper considers how sport presents a dualism to those on the far left of the political spectrum. A long-standing, passionate debate has existed on the contradictory role played by sport, polarised between those who reject it as a bourgeois capitalist plague and those who argue for its reclamation and reformation. A case study is offered of a political party that has consistently used revolutionary Marxism as the basis for its activity and how this party, the largest in Britain, addresses sport in its publications. The study draws on empirical data to illustrate this debate by reporting findings from three socialist publications. When sport did feature it was often in relation to high profile sporting events with a critical tone adopted and typically focused on issues of commodification, exploitation and alienation of athletes and supporters. However, readers’ letters, printed in the same publications, revealed how this interpretation was not universally accepted, thus illustrating the contradictory nature of sport for those on the far left

    EC03-1884 Wheat Disease Profiles I

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    This two-page, 4-color extension circular covers the disease and symptoms of wheat in Nebraska. The diseases listed are: barley yellow dwarf, soil-borne wheat mosaic, wheat streak mosaic, leaf rust, stem rust, stripe rust, tan spot, septoria leaf blotch, common root rot, crown rot, Fusarium head blight (scab)

    Patient perceptions of treatment and illness when prescribed multiple medicines for co-morbid type 2 diabetes

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    Illness and treatment perceptions are vital for people self-managing co-morbid conditions with associated cardiovascular disease, such as type 2 diabetes (T2D). However, perceptions of a co-morbid condition and the use of multiple medicines have yet to be researched. This study investigated the illness and treatment perceptions of people with co-morbid T2D. The Brief Illness Perception Questionnaire (repeated for T2D, hypertension, and hyperlipidemia) and the Beliefs about Medicines Questionnaire Specific Concerns Scales (repeated for Oral hypoglycemic agents, anti-hypertensive medicines, and statins) were sent to 480 people managing co-morbid T2D. Data on the number of medicines prescribed were collected from medical records. Significantly different perceptions were found across the illnesses. The strongest effect was for personal control; the greatest control reported for T2D. Illness perceptions of T2D differed significantly from perceptions about hyperlipidemia. Furthermore, illness perceptions of T2D also differed from perceptions of hypertension with the exception of perceptions of illness severity. Hypertension and hyperlipidemia shared similar perceptions about comprehensibility, concerns, personal control, and timeline. Significant differences were found for beliefs about treatment necessity, but no difference was found for treatment concerns. When the number of medicines was taken as a between-subjects factor, only intentional non-adherence, treatment necessity beliefs, and perceptions of illness timeline were accounted for. Co-morbid illness and treatment perceptions are complex, often vary between illnesses, and can be influenced by the number of medicines prescribed. Further research should investigate relationships between co-morbid illness and treatment perception structures and self-management practices

    EC03-1884 Wheat Disease Profiles I

    Get PDF
    This two-page, 4-color extension circular covers the disease and symptoms of wheat in Nebraska. The diseases listed are: barley yellow dwarf, soil-borne wheat mosaic, wheat streak mosaic, leaf rust, stem rust, stripe rust, tan spot, septoria leaf blotch, common root rot, crown rot, Fusarium head blight (scab)
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