680 research outputs found
Real-time simulation of jet engines with digital computer. 1: Fabrication and characteristics of the simulator
The fabrication and performance of a real time jet engine simulator using a digital computer are discussed. The use of the simulator in developing the components and control system of a jet engine is described. Comparison of data from jet engine simulation tests with actual engine tests was conducted with good agreement
The chemotherapeutic agent DMXAA as a unique IRF3-dependent type-2 vaccine adjuvant
5,6-Dimethylxanthenone-4-acetic acid (DMXAA), a potent type I interferon (IFN) inducer, was evaluated as a chemotherapeutic agent in mouse cancer models and proved to be well tolerated in human cancer clinical trials. Despite its multiple biological functions, DMXAA has not been fully characterized for the potential application as a vaccine adjuvant. In this report, we show that DMXAA does act as an adjuvant due to its unique property as a soluble innate immune activator. Using OVA as a model antigen, DMXAA was demonstrated to improve on the antigen specific immune responses and induce a preferential Th2 (Type-2) response. The adjuvant effect was directly dependent on the IRF3-mediated production of type-I-interferon, but not IL-33. DMXAA could also enhance the immunogenicity of influenza split vaccine which led to significant increase in protective responses against live influenza virus challenge in mice compared to split vaccine alone. We propose that DMXAA can be used as an adjuvant that targets a specific innate immune signaling pathway via IRF3 for potential applications including vaccines against influenza which requires a high safety profile
Linear-stability analysis of plane beds under flows with suspended loads
Plane beds develop under flows in fluvial and marine environments; they are recorded as parallel lamination in sandstone beds, such as those found in turbidites. However, whereas turbidites typically exhibit parallel lamination, they rarely feature dune-scale cross-lamination. Although the reason for the scarcity of dune-scale cross-lamination in turbidites is still debated, the formation of dunes may be dampened by suspended loads. Here, we perform, for the first time, linear-stability analysis to show that flows with suspended loads facilitate the formation of plane beds. For a fine-grained bed, a suspended load can promote the formation of plane beds and dampen the formation of dunes. These results of theoretical analysis were verified with observational data of plane beds under open-channel flows. Our theoretical analysis found that suspended loads promote the formation of plane beds, which suggests that the development of dunes under turbidity currents is suppressed by the presence of suspended loads.</p
Pressure dependent electronic properties of MgO polymorphs: A first-principles study of Compton profiles and autocorrelation functions
The first-principles periodic linear combination of atomic orbitals method
within the framework of density functional theory implemented in the CRYSTAL06
code has been applied to explore effect of pressure on the Compton profiles and
autocorrelation functions of MgO. Calculations are performed for the B1, B2,
B3, B4, B8_1 and h-MgO polymorphs of MgO to compute lattice constants and bulk
moduli. The isothermal enthalpy calculations predict that B4 to B8_1, h-MgO to
B8_1, B3 to B2, B4 to B2 and h-MgO to B2 transitions take place at 2, 9, 37, 42
and 64 GPa respectively. The high pressure transitions B8_1 to B2 and B1 to B2
are found to occur at 340 and 410 GPa respectively. The pressure dependent
changes are observed largely in the valence electrons Compton profiles whereas
core profiles are almost independent of the pressure in all MgO polymorphs.
Increase in pressure results in broadening of the valence Compton profiles. The
principal maxima in the second derivative of Compton profiles shifts towards
high momentum side in all structures. Reorganization of momentum density in the
B1 to B2 structural phase transition is seen in the first and second
derivatives before and after the transition pressure. Features of the
autocorrelation functions shift towards lower r side with increment in
pressure.Comment: 19 pages, 8 figures, accepted for publication in Journal of Materials
Scienc
A nested case–control study of the association of Helicobacter pylori infection with gastric adenocarcinoma in Korea
In a nested case–control study of 86 cases of gastric adenocarcinoma in relation to Helicobactor pylori infection in the Korean Multi-center Cancer Cohort, the H. pylori IgG seropositivity was 83.7% and that of the 344 matched controls was 80.8%, with a matched odds ratio for H. pylori infection of 1.06 (95% CI, 0.80–1.40)
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