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31.
Ten axenic isolates of Trichomonas vaginalis were subcutaneously injected to the BALB/c mice in order to assess their pathogenicity by means of so-called "mouse assay" method. All the isolates revealed neutral and acid proteinase activities both in their lysates and in culture media, but the specific activities of both proteinases in the severely pathogenic group were significantly higher than the mildly pathogenic group (p < 0.05). In the SDS-PAGE system in which the electrophoretic gels contained 0.4% gelatin as the substrate, five different banding patterns of trichomonal proteinases were detected, and the patterns were closely related with the pathogenicity of the isolates of T. vaginalis. All five bands might be regarded as cysteine proteinases group in the inhibitor assays. The cytotoxicity of the lysates of T. vaginalis to the target Chinese hamster ovarian (CHO) cell line was also significantly different according to the pathogenicity of the isolates, and generally lower in the lysates treated with cysteine proteinase inhibitors than in the control lysates. In summarizing the results, it might be considered that the proteinases of T. vaginalis showing five electrophoretic banding patterns are closely related with the pathogenicity and cytotoxicity of the isolates of T. vaginalis. 相似文献
32.
为了缓解状态空间爆炸问题,减小模型检测过程中生成的状态空间,加快模型检测速度,引入有限精度时间自动机(finite precision timed automata,简称FPTA)作为实时系统的形式模型,并提出了一种数据结构SDS(series of delay sequence)符号化表示状态空间中的状态集.FPTA只记录时钟变量的整数值及时钟变化的先后次序,从而减小生成的状态空间.在一定的时间约束下,Alur与Dill提出的时间自动机的可达性检测可简化为FPTA的可达性检测.举例描述了状态空间的生成过程和表示方法.最后,列出部分初步的实验结果,分析了SDS的特点及不足. 相似文献
33.
Young‐Sam Cho Seyoung Im 《International journal for numerical methods in engineering》2006,65(4):494-516
Two‐dimensional variable‐node elements compatible with quadratic interpolation are developed using the moving least‐square (MLS) approximation. The mapping from the parental domain to the physical element domain is implicitly obtained from MLS approximation, with the shape functions and their derivatives calculated and saved only at the numerical integration points. It is shown that the present MLS‐based variable‐node elements meet the patch test if a sufficiently large number of integration points are employed for numerical integration. The cantilever problem with non‐matching meshes is chosen to check the feasibility of the present MLS‐based variable‐node elements, and the result is compared with that from the lower‐order case compatible with linear interpolation. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
34.
C. H. Brown Elliott T. L. Credelle S. Han M. H. Im M. F. Higgins P. Higgins 《Journal of the Society for Information Display》2003,11(1):89-98
Abstract— Color subpixel rendering is enhanced by co‐optimizing the color subpixel architecture and algorithms with respect to human vision. This has resulted in the PenTile? display technology, which provides double the information content per subpixel when compared to a conventional RGB Stripe display. Output performance results from mathematical modeling, software simulations, and prototype AMLCDs displays demonstrate significant quality improvements to both text and full‐color images in comparison to images from RGB Stripe displays that have the same number of subpixels and column drivers. 相似文献
35.
I. Karaman J. Robertson J.- -T. Im S. N. Mathaudhu K. T. Hartwig Z. P. Luo 《Metallurgical and Materials Transactions A》2004,35(1):247-256
In this study, gas-atomized amorphous Zr58.5Nb2.8Cu15.6Ni12.8Al10.3 (Vitreloy 106a) containing 1280 ppmw oxygen was consolidated by equal-channel angular extrusion (ECAE). The powder was vacuum
encapsulated in copper cans and subjected to one extrusion pass in the temperature region above the glass transition temperature
(T
g) and below the crystallization temperature (T
x). The effects of extrusion temperature and the extrusion rate on microstructure, thermal stability, hardness, and compressive
strength are investigated. Compression fracture surfaces were examined to determine the deformation mechanisms. The consolidates
in which the time-temperature-transformation (TTT) boundary was not crossed during processing exhibit differential scanning
calorimetry (DSC) patterns similar to the initial powder, with a slight decrease in T
x. Compressive strengths of about 1.6 GPa are recorded in the consolidates processed at 30 °C and 40 °C below T
x, which is close to what is observed in cast counterparts. The fracture surfaces exhibit vein patterns covering up to 90 pct
of the surface area in some samples, which are characteristic of glassy material fracture. The slight decrease in T
x after consolidation is attributed to thermal-history-dependent short-range order and formation of nanocrystalline islands.
The present results show that ECAE is successful in consolidation of metallic glass powder. This processing avenue opens a
new opportunity to fabricate bulk metallic glasses (BMGs) with dimensions that may be impossible to achieve by casting methods. 相似文献
36.
O. Auciello S. Saha D.Y. Kaufman S.K. Streiffer W. Fan B. Kabius J. Im P. Baumann 《Journal of Electroceramics》2004,12(1-2):119-131
Thin films of Ba1?x Sr x Ti1+y O3+z (BST), were fabricated using both by RF-magnetron sputtering and MOCVD to demonstrate application to high frequency devices. Precise control of composition and microstructure is critical for the production of (Ba x Sr1?x )Ti1+y O3+z (BST) dielectric thin films with the large dependence of permittivity on electric field, low losses, and high electrical breakdown fields that are required for successful integration of BST into tunable high frequency devices. Here we review results on composition-microstructure-electrical property relationships of polycrystalline BST films produced by magnetron sputter deposition that are appropriate for microwave devices such as phase shifters. BST films with a multilayer structure were also developed with different Ti-elemental ratio in each layer to minimize losses and leakage current. Interfacial contamination from C and H species was studied and implications on electrical properties are highlighted. Finally, York's group at the University of California-Santa Barbara successfully integrated our BST films onto phase shifter arrays. The results show potential of BST films in such applications. Results from initial work on the integration of Cu-electrodes with BST films are also presented. 相似文献
37.
38.
Young?Tae?Im Seung?Tae?ChoiEmail author Tae?Sang?Park Jae?Hyun?Kim 《Journal of Mechanical Science and Technology》2004,18(1):12-19
Using LSM (laser scanning method), the radius of curvature due to thermal deformation in polyimide film coated on Si substrate
is measured. Since the polyimide film shows viscoelastic behavior, i.e., the modulus and deformation of the film vary with
time and temperature, we estimate the relaxation modulus and the residual stresses of the polyimide film by measuring the
radius of curvature and subsequently by performing viscoelastic analysis. The residual stresses relax by an amount of 10%
at 100°C and 20% at 150°C for two hours. 相似文献
39.
Kapp N Kreyling W Schulz H Im Hof V Gehr P Semmler M Geiser M 《Microscopy research and technique》2004,63(5):298-305
Epidemiologic studies have associated cardiovascular morbidity and mortality with ambient particulate air pollution. Particles smaller than 100 nm in diameter (ultrafine particles) are present in the urban atmosphere in very high numbers yet at very low mass concentration. Organs beyond the lungs are considered as targets for inhaled ultrafine particles, whereby the route of particle translocation deeper into the lungs is unclear. Five rats were exposed to aerosols of ultrafine titanium dioxide particles of a count median diameter of 22 nm (geometric standard deviation, GSD 1.7) for 1 hour. The lungs were fixed by intravascular perfusion of fixatives immediately thereafter. TiO(2) particles in probes of the aerosol as well as in systematic tissue samples were analyzed with a LEO 912 transmission electron microscope equipped with an energy filter for elemental microanalysis. The characteristic energy loss spectra were obtained by fast spectrum acquisition. Aerosol particles as well as those in the lung tissue were unambiguously identified by electron energy loss spectroscopy. Particles were mainly found as small clusters with a rounded shape. Seven percent of the particles in the lung tissue had a needle-like shape. The size distribution of the cluster profiles in the tissue had a count median diameter of 29 nm (GSD 1.7), which indicates no severe clustering or reshaping of the originally inhaled particles. Electron energy loss spectroscopy and related analytical methods were found to be suitable to identify and localize ultrafine titanium dioxide particles within chemically fixed and resin-embedded lung tissue. 相似文献
40.
Kyoungo Nam Hyunki Park Kihak Im Dongjin Kim Heejae Ahn Jaehyuk Lee Jaewhan Moon Emma Watson Robert Shaw 《Fusion Engineering and Design》2013,88(6-8):701-704
The purpose-built, ITER tokamak assembly tools, which are to be provided by Korea, should be designed to meet: the assembly plan, space reservations, safety standards, simple operations, efficient maintenance, and so on. It is very important that the ITER assembly tools are able to lift and transfer ITER components or their sub-assemblies to their assembled position safely. Furthermore, the lifting tools will lift and handle very heavy loads that can be more than 1200 tonnes sometimes. Therefore, the ITER lifting tools must be designed to endure these heavy load conditions with regard to their structural integrity. Also, these designs should be verified through an appropriate method. The preliminary design of the sector lifting tool and associated lifting attachments are introduced in this paper. The sector lifting tool was designed especially to lift and handle various ITER components by adjusting the lifting centre. The structural analysis results using ANSYS are described considering the heaviest load condition. The results of the analysis show that; all stresses applied on the lifting tool are lower than the allowable stress of the applied material. 相似文献