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41.
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LP Bignold 《Canadian Metallurgical Quarterly》1980,12(2):169-179
Increased vascular permeability of synovium induced by experimental haemarthrosis was studied in the stifle joint of the rat. Abnormal permeability was detected by injecting animals intravenously with colloidal carbon and examining the synovial vessels for intramural deposits of carbon. Both fresh and heparinized whole blood injected into the joint induced a marked permeability response of synovial venules which persisted for 18 hours. Platelets suspended in heparinized Tyrode solution induced a similar response, but one lasting only 12 hours. The permeability effects of suspensions of leucocytes and erythrocytes on the synovial vasculature were relatively mild and were maximal 5 and 12 h respectively after intra-articular injection. Heparinized platelet-free plasma had no significant permeability effects. These results indicate that platelets may play an important role in the pathogenesis of synovial inflammation in haemarthrosis. 相似文献
43.
The reliable pressure readings with a capacitance manometer are the basis for a new type of instrument designed for accurate and rapid measurements of capillary volumes. The basic measuring principle is based on expansion of air atmospheric pressure enclosed in a known volume into a pre-evacuated cylinder so that the enclosed volume will cause a reduced pressure in the cyllinder. The same is done with the air in an unknown volume into another identical pre-evacuated cylinder. A differential capacitance manometer is then used to measure the difference in pressure between the two cylinders with a high degree of accuracy. This difference in pressure is shown to be ainear function of the difference in volume between the unknown and the known volume. The accuracy and repeatability of the instrument is better than 0.5%. 相似文献
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JM Koelman HJ Noteborn de Goey LP BJ Verhaar JT Walraven 《Canadian Metallurgical Quarterly》1985,32(11):7195-7198
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Alexandre Pimenta Ciniro A. L. Nametala Frederico G. Guimarães Eduardo G. Carrano 《Computational Economics》2018,52(1):125-144
Stock market automated investing is an area of strong interest for the academia, casual, and professional investors. In addition to conventional market methods, various sophisticated techniques have been employed to deal with such a problem, such as ARCH/GARCH predictors, artificial neural networks, fuzzy logic, etc. A computational system that combines a conventional market method (technical analysis), genetic programming, and multiobjective optimization is proposed in this work. This system was tested in six historical time series of representative assets from Brazil stock exchange market (BOVESPA). The proposed method led to profits considerably higher than the variation of the assets in the period. The financial return was positive even in situations in which the share lost market value. 相似文献
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Marcos Pimenta de Abreu 《Computer Physics Communications》2008,179(6):380-384
In this article, we make use of recently developed spectral nodal methods for anisotropically scattering media and we derive mathematical conditions for the diffuse reflection and transmission of radiation in the discrete ordinates formulation of particle transport theory for plane-parallel applications. The conditions arise from a suitable reformulation of spatially discretized equations defined on the boundary layers of a multislab domain. As a result, the boundary layers can be removed from the radiation transport calculations and replaced with exact and numerically stable equivalent conditions. In order to illustrate the applicability and computational merit of our discrete ordinates conditions for diffuse reflection and transmission in radiation transport calculations, we perform numerical experiments with atmospheric radiative transfer and nuclear reactor core models. 相似文献