95 research outputs found

    Evaluation of seven tumour markers in pleural fluid for the diagnosis of malignant effusions

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    Carcinoembryonic antigen (CEA), carbohydrate antigens 15–3, 19–9 and 72–4 (CA 15–3, CA 19–9 and CA 72–4), cytokeratin 19 fragments (CYFRA 21–1), neuron-specific enolase (NSE) and squamous cell carcinoma antigen (SCC) were evaluated in pleural fluid for the diagnosis of malignant effusions. With a specificity of 99%, determined in a series of 121 benign effusions, the best individual diagnostic sensitivities in the whole series of 215 malignant effusions or in the subgroup of adenocarcinomas were observed with CEA, CA 15–3 and CA 72–4. As expected, a high sensitivity was obtained with SCC in squamous cell carcinomas and with NSE in small-cell lung carcinomas. CYFRA and/or CA 15–3 were frequently increased in mesotheliomas. Discriminant analysis showed that the optimal combination for diagnosis of non-lymphomatous malignant effusions was CEA + CA 15–3 + CYFRA + NSE: sensitivity of 94.4% with an overall specificity of 95%. In malignant effusions with a negative cytology, 83.9% were diagnosed using this association. The association CYFRA + NSE + SCC was able to discriminate adenocarcinomas from small-cell lung cancers. Regarding their sensitivity and their complementarity, CEA, CA 15–3, CYFRA 21–1, NSE and SCC appear to be very useful to improve the diagnosis of malignant pleural effusions. © 1999 Cancer Research Campaig

    The James Webb Space Telescope Mission

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    Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4m4m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5m6.5m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

    Validation and Assessment of DLR and ONERA Euler Codes for Multibladed Rotors in Hover

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    Two different Euler codes for hovering rotor calculations, developed by DLR and ONERA, are compared and assessed using common computational grids. The tests are based on the Caradonna-Tung data base and on the new HELISHAPE tests with 4-bladed 7A rotor, scheduled for end of 1995. For all test cases the predicted pressure distributions of both codes are in good agreement. Considering that Euler calculation do not account for viscous effects the predicted surface data also compare well with experiments. A detailed comparison of the wake and tip vortex representation by both Euler methods shows some differences. The strong effects of numerical diffusion on wake resolution are demonstrated. It is found that a detailed wake and vortex representation hinders the convergence to steady state of the Euler methods, particularly the integrated flow quantities oscillate with iteration in a low-

    Euler Calculations of Multibladed Rotors in Hover by DLR and ONERA Methods and Comparison with HELISHAPE Tests

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    Within the European Project HELISHAPE, the Euler methods of multibladed rotors in hoverflight, developed respectively by DLR and ONERA, have been compared and assessed. No wake model is used by both methods. The computations are performed as blind-test calculations on common single-block structured grids. The test cases arae the HELISHAPE hover experiments with the 4-bladed 7A rotor and 7A-D1 rotor. These rotors are scaled versions of realistic helicopter rotors with an aspect ratio of 15. For all test cases the predicted pressure distributions of both codes are in good agreement. Considering that Euler calculation do not account for viscous effects the predicted surface data also compare well with experiments. A detailed comparison of the wake and tip vortex representation by both Euler methods shows some differences. The strong effects of numerical diffusion on wake resolution are demonstrated

    Helicopter Rotor Noise Prediction Using ONERA and DLR Euler/ Kirchhoff Methods

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    Euler/Kirchhoff methods have been developed at ONERA and DLR to predict the High Speed Impulsive (HSI) noise generated by helicopter rotors in hover or in forward flight. The main purpose of this common work is to validate the aeroacoustic computations with delocalized test cases. In hover, the aerodynamic and acoustic results obtained by each partner are in good agreement with experiment. In forward flight, a first set of computations is performed with three different sized "classical" grids. For both partners, the pressure coefficients on the blade are in better correlation with experiment when the grid is refined. However, the capture of the shock waves propagation beyond the blade is not accurate enough to perform satisfactory Kirchhoff computations. The minimum pressure peak and the recompression slope of the acoustic pressure signatures are not accurately predicted, whatever the grid refinement of the Kirchhoff surface locations may be. An

    Experimental investigation of spray combustion regimes in aeroengine combustors

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    At ONERA Fauga-Mauzac center, a new air-breathing propulsion test setup, Prométhée-LACOM, has been recently developed. In this paper, both nonreacting and reacting two-phase flows (nonpremixed spray) were investigated. Under reactive conditions, simultaneous OH-PLIF (planar laser-induced fluorescence) and Mie scattering imaging were implemented in order to characterize the spray flame structure. The different behaviors observed in this study seem to support the existence of spray combustion regimes. Moreover, statistical analysis was performed on the spatial distribution of droplets and indicated that the center-to-center interdroplet distance (nearest neighbor) could be described by means of a perfectly random distribution

    Low Mach Number Preconditioning for Unsteady Flow in General "ALE" Formulation

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