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Mifepristone (RU486) is a chemical contraceptive marketed in more than 55 countries and used by hundreds of millions of women worldwide. Current studies reported its uses by both genders for a safe and long-term psychotic depression and particularly for traditional cancer chemotherapy. Here, we investigated the multidisciplinary data from recent large epidemiological chemoprevention studies for long-term use of oral contraceptives to reduce cancer risk, and from the unsuccessful clinical trials of mifepristone used as a post-metastatic anticancer drug, and elucidated the similarities and differences in cellular and molecular processes between embryonic implantation to endometrium and adhesion/invasion of circulating tumor cells (CTCs) to vascular endothelium. The deep analyses provide a stronger scientific basis for repurposing abortifacients for safe and effective cancer metastatic chemoprevention. Initiation of such cancer drug development strategy represents a paradigm shift from traditional post-metastasis treatments to novel pre-metastasis chemoprevention.

The performance of an optimized aerodynamic shape is further improved by a second-step optimization using the design knowledge discovered by a data mining technique based on Proper Orthogonal Decomposition (POD) in the present study. Data generated in the first-step optimization by using evolution algorithms is saved as the source data, among which the superior data with improved objectives and maintained constraints is chosen. Only the geometry components of the superior data are picked out and used for constructing the snapshots of POD. Geometry characteristics of the superior data illustrated by POD bases are the design knowledge, by which the second-step optimization can be rapidly achieved. The optimization methods are demonstrated by redesigning a transonic compressor rotor blade, NASA Rotor 37, in the study to maximize the peak adiabatic efficiency, while maintaining the total pressure ratio and mass flow rate. Firstly, the blade is redesigned by using a particle swarm optimization method, and the adiabatic efficiency is increased by 1.29%. Then, the second-step optimization is performed by using the design knowledge, and a 0.25% gain on the adiabatic efficiency is obtained. The results are presented and addressed in detail, demonstrating that geometry variations significantly change the pattern and strength of the shock wave in the blade passage. The former reduces the separation loss, while the latter reduces the shock loss, and both favor an increase of the adiabatic efficiency. Keywords: Aerodynamic shape optimization, Computational fluid dynamics, Data mining, Particle swarm optimization, Proper Orthogonal Decomposition, Transonic flow, Turbomachinery

Grid adaption is a popular method to enhance the resolution of flow field and the precision of numerical simulation, which automatically optimizes the grid distribution instead of manual complicated work. There exist usually two grid adaptation methods, the feature based grid adaption and adjoint based grid adaption, the former focuses on shocks, vortexes and other features of flow field, and the latter focuses on lift, drag and other aerodynamic characteristics. The comparison of adjoint based grid adaption and feature based grid adaption method is investigated in this paper. Numerical simulations show that both feature adaption and adjoint adaption could improve the resolution of flow field and the precision of numerical simulation such as lift and drag. As for the flow features, the feature adaptation could capture the obvious shock waves and vortexes in the flow field, the adjoint adaptation, however, only captures the flow features that are contributory to the accuracy of aerodynamic characteristics. As for the aerodynamic characteristics, some shock waves and vortexes have little influences to the forces, so the feature adaptation is not efficient as adjoint adaptation, which could greatly improve the accuracy of aerodynamic characteristics.

Tilt-rotor aircraft combines the vertical take-off and landing function of helicopters with the high-speed cruise function of fixed-wing aircraft, which has given rise to extensive attention in the aviation field, but the complex aerodynamic characteristics of the rotor flow field and the interference of rotor/fuselage have always been tough problems. In recent years, the continuous development of high-performance computer and the combination of high-precision CFD method and dynamic overset grid technology, make it possible to perform fine numerical simulation of tilt-rotor aircraft’s flow field. In this paper, the low-dissipation fifth-order Roe-WENO scheme and overset grid method are used to solve the unsteady N-S equation, and the hovering state of tilt-rotor aircraft is numerically simulated. The result shows: under the interference of ground effect and fountain effect, the lift coefficient of blade when the azimuth angle is 180° to 360° is obviously smaller than that when the azimuth angle is 0° to 180°. The vortex structure of the hovering flow field of V-22 tilt-rotor aircraft is mainly composed of the fountain effect recirculation zone, the tip vortex wake and the root vortex wake. The tip vortex wake develops downwards, shrinks inward and approaches the fuselage. After the root wake falls off, it converges and fuses on the surface of nacelles. The root vortex wake is strong and moves towards the front of the fuselage and the plane of symmetry.

Numerical investigations of the NASA Common Research Model from the 6th AIAA CFD Drag Prediction Workshop are performed with in-house solver MFlow. The solver is based on a cell-centered finite vol...

Molecular dynamics (MD) simulations coupling multi-scale shock technique (MSST) are performed to study the shock Hugoniot and Mie-Gruneisen equation of state (EOS) for TiAl alloy. The accuracy of the EAM potential for TiAl is examined by both melting temperature at a free pressure and Hugoniot curve. The material composition seriously affects the linear relation of shock wave velocity and particle velocity, Hugoniot curve, and internal energy. The Born-Mayer potential and Morse potential both can describe the cold curve at lower compressions, while the cold curve described via the Born-Mayer potential is larger than that of Morse potential at higher compressions. The shock melting temperature (Tm) is totally determined by Gruneisen coefficient γ, which shows an opposite trend as compared with the increasing Tm at the whole compressions. Mie-Gruneisen EOS presents a concave surface in pressure – specific volume – internal energy (P-V-E) space, which is independent of the reference curves utilized the cold curve and Hugoniot curve.

The severe soil deterioration and the accompanying decline in maize yield are the main factors jeopardizing the sustainability of agricultural production in the black soil region of Northeast China. Conservation tillage practices have been proposed as new practices to enhance soil fertility and to produce food from a dwindling land resource in this region, but wide adoption of these practices can occur only when the practices demonstrate a steady increase in agricultural production. To compare the effects of tillage on corn yield, the structural equation modeling (SEM) was used in analyzing the relationships between maize growth/yield and soil properties (physical and chemical characteristics) based on a long-term (12 years) tillage study that included no tillage (NT), ridge tillage (RT) and conventional tillage (CT) practices. Compared with CT, NT and RT had higher maize grain yield, soil carbon/nitrogen ratio and soil moisture, and lower soil temperature and seedling emergence rate. The advantages of NT and RT in maize yield were primarily ascribed to the favorable soil nutrients and soil water content, which could increase plant size at the later growing season and ultimately yield more maize grain. The lower soil temperature and subsequently lower emergence rates in NT and RT at early stages (sowing to emergence) of maize growth did not exert negative effects on maize yield. These adverse effects of low soil temperature and low emergence rates could be offset by postponing sowing date without compromising the maize yield. Our study indicated that both NT and RT practices could offer a potentially significant improvement over the current conventional tillage practice in the black soil region of Northeast China.

Bulky 2-pyridinemethanamine nickel complex activated by MAO was used as a catalyst to conduct longstanding living ethylene polymerization under atmospheric pressure to produce branched polyethylene.