The multimedia proxy plays an important role in media streaming applications. In this paper, we propose an architecture for a multimedia proxy across the wireless Internet. By considering multiple ...objectives of the multimedia proxy, we design a unified cost metric to measure proxy performance in the wireless Internet. Furthermore, we propose a cost-based replacement policy for the wireless Internet to improve performance such as throughput, media quality, and startup delay. Simulation results demonstrate that our policy achieves significantly better performance than the conventional replacement policy.
In order to realize the practical application of TiAl alloys in automobile industry, the possibility of decreasing cost of engine components by applying low-cost and recycled raw materials, in place ...of expensive elemental powders, was investigated. The TiAl exhaust valves with a relative density of 99% were made from chip Al and sponge Ti/Titanium Hydride (TiH2) through the Mechanical Alloying-Pulse Discharge Sintering technique (MA-PDS). The sintered specimens from the sponge TiH2/chip-Al system have the same level of fracture strength as those sintered from the powdered Ti/Al system, although the commercial price of TiH2 is only one third that of Ti powder and the price of chip Al is one sixteenth that of Al powder. XRD results showed that specimens from the TiH2/chip-Al system consisted of duplex phases of TiAl and Ti3Al, which is identical with that of specimens from the Ti/Al powder system. On the other hand, the specimens from sponge-Ti/chip-Al system with the lowest cost have slightly lower mechanical properties caused by the unexpected coarse Al-rich phase.
Diethyldithiocarbamate (DTC), a biological augmenting agent specific for T cells, was applied to treat patients with incipient oral lichen planus (OLP) who had been refractory to traditional therapy. ...DTC was administered orally (5 mg.kg-1, twice a week) for at least 3 months. Interleukin 2 (IL-2) production and lymphocyte proliferation of peripheral blood mononuclear cells (PBMC) were measured before and after the treatment. The bioactivity of IL-2 was determined by the use of IL-2 dependent cell line CTLL-2 and human recombinant IL-2. The results indicated that both IL-2 production of PBMC and lymphocyte proliferation increased (P less than 0.01). Clinical symptoms were improved significantly. The effective rate in 30 patients was 86.7%. It is suggested that the mechanism involves that DTC improves the cellular immunity of the patients.
Staphylococcus aureus rich in protein A when coated with monoclonal antibodies (MoAb) to Japanese encephalitis virus (JEV) gave a highly specific reaction with flavivirus antigens. The bacteria ...coated with JEV species-specific MoAb gave a strong co-agglutination with fifty-six JEV isolates from various parts of China, but no co-agglutination with Murray Valley encephalitis (MVE) and Kunjin (Kun) virus antigens. The flavivirus- and subgroup-specific MoAbs were reactive with MVE and Kun, as well as with the majority of the JEV strains. Blocking test with homologous MoAbs abolished co-agglutination further confirming its specificity. Numerous virus particles were observed on the surface of MoAb-coated staphylococci under the electron microscope after co-agglutination. The test appeared rapid, specific, simple to perform, and useful for rapid detection and identification of flaviviruses.
A damage model of low cycle shear fatigue has been developed in dislocation theory. On the basis of this model, a formula including the factors of thermal cycle temperature, dwell time, and ...atmospheric oxidation has been established to predict the life of surface mount technology (SMT) solder joints under thermal cycling. This formula has been verified by experiments on the specimens of actual SMT assemblies. The results show that the life formula established coincides with the experimental results.< >
Solid tumors require an adequate vascular supply to grow beyond a certain dimension. It is known that formation of new blood vessels in tumor is mediated by unbalanced expression of angiogenic ...factors and their inhibitors. Among the former, the vascular endothelial growth factor (VEGF) has been assumed prime candidacy as a major positive physiological effector. To investigate the role of VEGF in angiogenesis associated with development of breast cancer, a sense VEGF and an anti-sense VEGF expression plasmids were constructed, and then were introduced into a human breast carcinoma cell line, MCF-7, expressing middle level of endogenous VEGF. Anti-sense VEGF(121) transfected MCF-7 cells that expressed reduced constitutive levels of VEGF and showed the same growing potential as untransfected MCF-7 cells in vitro, but it showed longer latency, smaller tumor, slower growth and prolonged survival time compared to parental or sense VEGF(165) transfected MCF-7 cells in vivo. Moreover, the tumors derived from anti-sen
A simple new method is reported for the identification of arbovirus isolates and the titration of arboviruses. Horseradish peroxidase conjugated Staphylococcus aureus protein A was used for the ...indirect staining of virus antigens grown in an Aedes albopictus cell line, C6/36 cells. Thirty-five isolates from Culex tritaeniorhynchus mosquitoes were examined by this method and 20 of these were identified as Japanese encephalitis virus (JEV). These results were confirmed by immunofluorescent assay and plaque neutralization test. Comparative titration of JEV, Murray Valley encephalitis (MVE) and Kunjin viruses showed that this method was as sensitive as the chick embryo plaque assay. Specific enzymatic reactions on these virus-infected cells began to appear before day 3 and reached the end-point on day 5 post-infection of C6/36 cells, whereas the cytopathic effect (CPE) appeared about 2 days later than the positive enzymatic reactions. Fixation with 10% formalin for 0.5-8 h did not damage the positive reaction in infected cells and did not increase the background colour of uninfected cells.
PDF
