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The aerodynamic configuration study of ATLLAS-M6 transport aircraft proposed by the German Aerospace Center (DLR) is presented and discussed. The ATLLAS-M6 has a turbine-based combined cycle (TBCC) propulsion system, and it's aerodynamic configuration has the following characteristics, double delta-wing with low-aspect ratio, axial vertical tail, high-set horizontal tail and lifting body with high-fineness ratio. In this paper, a parameterized configuration is proposed via the "class function and shape function transformation technique" (CST) method. The aerodynamic characteristics are investigated, such as the trim characteristic, static/dynamic stability and control efficiency of control surfaces. The detail research indicated that the ATLLAS-M6 analog has a high hypersonic lift to drag ratio at the cruise state of low trimming angle of attack. The hypersonic stability derivatives predicted by the "dahlem-buck" method and the "prandtl-meyer" method shown that the transporter is static and dynamic stable in both lateral and directional directions and the proposed configuration is one of the feasible transporter choices. Yet, the aerodynamic configuration conceptual design of the hypersonic transport aircraft is a highly integrated project, several disciplines involved must be considered farther, such as structured materials and thermal protection system. Therefore, the "multidisciplinary design optimization" (MDO) method would be used to optimize the ATL LAS-M6 analog aerodynamic configuration at the farther work. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the efficacy and safety of entecavir (ETV) treatment for chronic severe hepatitis B., Methods: 78 patients with chronic severe hepatitis B and positive HBV DNA were divided into ETV group and control group, each group had 39 patients. ETV group was given the same conventional therapy as control group, and was treated with ETV. The change of liver function, PTA, HBV DNA level were observed, and adverse events were recorded. The effective rate of treatment between ETV group and control group, the baseline characteristics between the effective cases and non-responsive cases after ETV treatment were compared at week 12., Results: The baseline characteristics were well balanced between ETV group and control group. The effective rate of ETV group was 56.41% versus 33.33% of control group at week 12 (P = 0.0405). The effective rate of ETV group was higher than that of control group, in the early stage of chronic severe hepatitis B (P = 0.0275), but there was no statistically significant in the middle or late stage (P = 0.4687). The comparison result of baseline characteristics between the effective and non-responsive cases after ETV treatment showed: there were statistically different in age, bilirubin level, HBV DNA level and stage of the severe hepatitis, proportion of cirrhosis, but no statistically different in cholinesterase level, alpha-fetoprotein level and sex ratio, the proportion of ascites, positive HBeAg (P > 0.05). No serious adverse events occurred., Conclusions: ETV improves the curative effect when used in the early stage of chronic severe hepatitis B, and may not in the middle and late stage. The curative effect of ETV may be affected by age, bilirubin level, HBV DNA level and stage of the severe hepatitis, cirrhosis. ETV has good security in the treatment for chronic severe hepatitis B.