BRMS1 performs an anti-tumor effect on renal cell carcinoma via inhibition of PI3K/AKT/mTOR signaling pathway

Objective:To explore the anti-tumor of breast cancer metastasis suppressor 1(BRMS1)on renal cell carcinoma.Methods:BRSM1 stabilized overexpressed and knockdown cell models were constructed to detect the effect of BRMS1 overexpression and knockdown on viability rate of 769-P cells.Activation of PI3K/AKT-mTOR-NFκB signaling pathway,expression of cellular apoptosis-related proteins,DNA damage repair-related proteins and angiogenesis-related proteins were detected using Western blotting analysis.Results:The viability rate of 769-P cells were significantly decreased in BRMS1 overexpression cells while significantly increased in BRMS1 knockdown cells(P<0.05).The activity of PI3K/AKT-mTOR-NFκB signaling pathway was significantly inhibited with BRMS1 overexpression(P<0.05),and expression of BAX was significantly increased with significantly decreased expression of Bcl-2(P<0.05).Besides,BRMS1 overexpression could significantly decrease the expression of DNA damage repair-related proteins and angiogenesis and cell-matrix degradation related proteins(P<0.05).Conclusion:BRMS1 induces apoptosis of renal cell carcinoma and performs an anti-tumor effect via inhibition of PI3K/AKT-mTOR-NFκB signaling pathway,expression of DNA damage repair-related proteins and angiogenesis-related proteins.

Flame quenching process in cavity based on model scramjet combustor

The flame quenching process in combustors was observed by high speed camera and Schlieren system, at the inflow conditions of Ma = 2.64, To = 1483K, P0 = 1.65 MPa, T = 724 K and P -- 76.3 kPa. Changing process of the flame and shock structure in the combustor was clearly observed. The results revealed that the precom- bustion shock disappeared accompanied with the process in which the flame was blown out and withdrawed from the mainflow into the cavity and vanished after a short while. The time of quenching process was extended by the cavity flame holder, and the ability of flame holding was enhanced by arranging more cavities in the downstream as well. The flame was blown from the upstream to the downstream, so the flame in the downstream of the cavity was quenched out later than that in the upstream.

Similarity measurement of Chinese medicine ingredients for cold-hot nature identification

目的:中药药性理论是中医药的核心基础理论,其中寒热药性是当前研究的重点。研究发现中药成分是产生药性的物质基础。因此,我们推断成分相似的中药具有相似的药性。由于中药指纹图谱可以反映中药的物质成分,因此,当前热点集中于通过中药指纹图谱技术研究中药药性。方法:为了验证上述假说,本文研究量化中药成分的相似性为指纹图谱的相似性,探索中药成分与寒热药性之间的关系。首先,我们利用紫外指纹图谱分析61味寒热药性明确的中药(30味寒性药和31味热性药)。其次,一个距离度量学习算法被研究度量中药指纹图谱的相似性。最后,一个检索方案被提出构建预测识别模型用于中药寒热药性的识别。结果:大量的实验发现,石油醚溶剂下的紫外图谱可以更好的区分寒热药性。与已有的识别方案相比,提出的模型具有更好的识别性能。结论:实验结果证明了我们的推论,成分相似的中药具有相似的药性。提出的预测模型被证明是可行和有效的。

Erosion behavior of a ship propeller material of QAl9-4 alloy

The erosion behavior of a QA19-4 alloy as a ship propeller material was investigated.The effects of the solution,the impact angles and the sand content were considered.The test results demonstrate that the mass loss of the alloy in 3.5 wt%NaCl solution is 1.35 times that in tap water,due to the corrosive effect of Cl^(-).The mass loss of the alloy increases as the impact angle increases up to~30°and consequently decreases as the impact angle increases.Also,this feature is typical for the ductile metal behavior.At the impact angle of 0°,this feature is associated with the predominant erosion mechanisms,such as shallow plowing and surface fatigue;at 30°,this feature is micro-cutting,deep plowing and surface fatigue;and at 45°,it becomes indentation accompanied by extruded lips.The mass loss and surface roughness of the alloy increase as the sand content increases under the testing conditions.

Progress of the 10 J water-cooled Yb:YAG laser system in RCLF

The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported.The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow.In the main amplifier,the laser is four-pass,and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test.The far-field of the output beam is approximately 10 times the diffraction limit.Because of the higher levels of amplified spontaneous emission(ASE) in the main amplifier,the output energy is lower than expected.At the end we discuss some measures that can improve the properties of the laser system.

Tribological behaviour of biomedical Ti–Zr-based shape memory alloys

The tribological behaviour of Ti-30Zr, Ti-20Zr-10Nb and Ti-19Zr-10Nb-1Fe alloys was investigated using reciprocating friction and wear tests. X-ray diffraction（XRD） results indicate that Ti-30Zr, Ti-20Zr-10Nb and Ti-19Zr-10Nb-1Fe alloys are composed of hexagonal a＇-martensite, orthorhombic a＇＇-martensite and bcc β phases,respectively. Ti-30Zr alloy has the highest hardness of HV（273.1 ± 9.3）, while Ti-20Zr-10Nb alloy exhibits the lowest hardness of HV（235.2 ± 20.4） among all the alloys.The tribological results indicate that Ti-30Zr alloy shows the best wear resistance among these alloys, corresponding to the minimum average friction coefficient of 0.052 and the lowest wear rate of 6.4x10^-4mm3·N^-1·m^-1. Ti-20Zr-10Nb alloy displays better wear resistance than Ti-19Zr-10Nb-1Fe alloy, because the iron oxide is easy to fall off and less Nb2O5 films form on the worn surface of the latter.Delamination and abrasive wear in association with adhesive wear are the main wear mechanism of these alloys.

火箭基组合循环发动机总体布局研究进展（英文）

本综述从总体布局层面综述火箭基组合循环(RBCC)发动机在各个国家的发展现状,旨在展现该型发动机在单级入轨任务中的发展前景,为设计组合循环发动机以及进行空天往返任务规划提供参考。本文将RBCC按照构型特点进行归类并举例介绍,概述了发动机-机身一体化设计情况,并简要介绍了RBCC动力飞行器的任务规划和多目标优化方法。当前,尽管RBCC的研究面临着很多艰难的挑战,但是RBCC具有单级入轨的潜力,能够降低空天往返的成本。对RBCC发动机系统中各个子系统的研究也有利于促进其他相关学科的发展。

Design method for hypersonic bump inlet based on transverse pressure gradient

Transverse pressure gradient(TPG)is one of the key factors influencing the boundary layer airflow diversion in a bump inlet.This paper proposes a novel TPG-based hypersonic bump inlet design method.This method consists of two steps.First,a parametric optimization approach is employed to design a series of 2D inlets with various compression efficiencies.Then,according to the prescribed TPG,the optimized inlets are placed in different osculating planes to generate a 3D bump inlet.This method provides a means to directly control the aerodynamic parameters of the bump rather than the geometric parameters.By performing this method to a hypersonic chin inlet,a long and wide bump surface is formed in the compression wall,which leads to good integration of the bump/inlet.Results show that a part of the near-wall boundary layer flow is diverted by the bump,resulting in a slight decrease in the mass flow but a significant improvement in the total pressure recovery.In addition,the starting ability is significantly improved by adding the bump surface.Analysis reveals that the bump has a 3D rebuilding effect on the large-scale separation bubble of the unstarted inlet.Finally,a mass flow correction is performed on the designed bump inlet to increase the mass flow to full airflow capture.The results show that the mass flow rate of the corrected bump inlet reaches up to 0.9993,demonstrating that the correction method is effective.

基于数值计算方法的翼型参数化、建模与优化研究（英文）

目的:1.比较并改善翼型参数化方法,获得设计变量少、拟合精度高的参数化方法;2.在参数化的基础上利用数值模拟的方法获取翼型流场参数,优化并获得特定条件下升阻比最大的翼型。创新点:1.通过与多项式拟合方法的对比证明了类别/形状函数转换(CST)法在翼型拟合方面的优越性,并通过调整控制点分布,在不增加设计变量的基础上改善了CST方法;2.通过建立响应面模型,利用多岛遗传算法与非线性序列二次规划法相结合的方式获得了更好的翼型优化效果。方法:1.利用修饰后的CST法对翼型进行参数化拟合与设计,并通过与二项式拟合法比较来验证其优越性;2.通过数值方法对翼型周围流场进行计算并与实验结果对比,获得精确计算气动参数的仿真条件;3.通过拉丁超立方采样获得设计变量,建立设计变量与翼型升阻比之间的响应面模型,通过多岛遗传算法与非线性序列二次规划法的结合和优化,得到一定条件下升阻比最大的翼型。结论:1.CST法是一种优秀的参数化方法,本文的优化改善了形状函数控制点选取法则,使其对翼型头部和尾部的描述更加精确;与多项式相比,CST法可以通过更少的设计变量得到更高的拟合精度。2.基于多岛遗传算法的非线性序列二次规划法在本文中用以优化翼型使其具有更高升阻比。优化前后翼型的比较显示,两种优化方法的结合可以得到比单独使用各优化方法更好的结果。

High-temperature deformation behavior of a beta Ti-3.0Al-3.5Cr-2.0Fe-0.1B alloy

The high-temperature deformation behavior of a beta Ti-3.0 Al-3.5 Cr-2.0 Fe-0.1 B alloy was investigated by a Gleeble-1500 D thermal simulator. The height reduction was 50%, corresponding to a true strain of 0.693. The strain rate ranging from 0.01 to 10.00 s^-1 and the deformation temperature ranging from 800 to 950 ℃ were considered.The flow stress and the apparent activation energy for deformation, along with the constitutive equation, were used to analyze the behavior of the Ti-3.0 Al-3.5 Cr-2.0 Fe-0.1 B alloy. The processing map was established. The effect of strain rate on the microstructure at 850 ℃ was evaluated.The flow stress-strain curves indicated that the peak flow stresses increased along with an increase in the strain rate and decreased as the deformation temperature increased.Based on the true stress-true strain curves, the constitutive equation was established and followed as the ε= 6.58×10-（10）[sinh（0.0113σ）]-（3.44）exp（-245481.3/RT）. The processing map exhibited the ＂unsafe＂ region at the strain rate of10 s^-1 and the temperature of 850 ℃,and the rest region was ＂safe＂. The deformation microstructure demonstrated that both dynamic recovery（DRV） and dynamic recrystallization（DRX） existed during deformation. At the lower strain rate of 0.01 s^-1, the main deformation mechanism was the DRV, and the DRX was the dominant deformation mechanism at the higher strain rate of 1.00 s^-1.

Influence of thermal reduced depolarization on a repetition-frequency laser amplifier and compensation

Thermal stress can induce birefringence in a laser medium, which can cause depolarization of the laser. The depolarization effect will be very severe in a high-average-power laser. Because the depolarization will make the frequency doubling efficiency decline, it should be compensated. In this paper, the thermal characteristics of two kinds of materials are analyzed in respect of temperature, thermal deformation and thermal stress. The depolarization result from thermal stress was simulated. Depolarization on non-uniform pumping was also simulated, and the compensation method is discussed.

Effects of bump parameters on hypersonic inlet starting performance

Unstart is an unwanted flow phenomenon in a hypersonic inlet. When an unstart occurs, the captured airflow flowing through the engine significantly decreases with strong unsteady characteristics, which may lead to thrust loss or even combustor flameout. In this study, various bump configurations were designed to be integrated with a hypersonic inlet to improve its starting ability. A bump was defined as an integrated 3D compression surface installed upstream of the inlet entrance. The starting processes of these bump inlets were numerically simulated to investigate the effect laws and flow mechanisms of the bump parameters. Tests on bump height revealed that the starting performance could be significantly improved by increasing bump height, with the starting Mach number decreasing by 0.55 for the inlet with the highest bump. The high bump facilitates the side movement of the subsonic flow in the separation zone, which leads to a small separation bubble, thus accelerating the starting process. Further, the starting ability can be improved by designing a relatively wide bump, which results in a decline in the starting Mach number by 0.44. When the bump has the same or greater width compared with the airflow capture range, a growing spillage along the transverse direction can be formed so that the airflow in the separation bubble can be easily excluded, improving the starting ability.

Stabilization mechanisms of lifted flames in a supersonic stepped-wall jet combustor

Flame stabilization is the key to extending scramjets to hypersonic speeds;accordingly,this topic has attracted much attention in theoretical research and engineering design.This study performed large eddy simulations(LESs)of lifted hydrogen jet combustion in a stepped-wall combustor,focusing on the flame stabilization mechanisms,especially for the autoignition effect.An assumed probability density function(PDF)approach was used to close the subgrid chemical reaction source.The reliability of the solver was confirmed by comparing the LES results with experimental data and published simulated results.The hydrogen jet and the incoming stream were first mixed by entraining large-scale vortices in the shear layer,and stable combustion in the near-wall region was achieved downstream of the flame induction region.The autoignition cascade is a transition of fuel-rich flame to stoichiometric ratio flame that plays a role in forming the flame base,which subsequently causes downstream flame stabilization.Three cases with different jet total temperatures are compared,and the results show that the increase in the total temperature reduces the lift-off distance of the flame.In the highest total temperature case,an excessively large scalar dissipation rate inhibits the autoignition cascade,resulting in a fuel-rich low-temperature flame.