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It is believed that isolated defects within the capsule (e.g., void, high-density inclusion) can be one of the essential factors for implosion performance degradation by seeding hydrodynamic instabilities in implosions. Nonetheless, a systematic study on how the isolated defects evolve and why they are not stabilized by ablation given the length scale comparable with the typical cutoff wavelength is still lacking. This paper addresses the above concerns by looking into a simplified model where a planar shell (without convergent geometry) is driven by laser direct-drive, with a single defect (low/high density) of micrometer or sub-micrometer scale residing at different locations inside. The underlying dynamics of two key physical processes are analyzed, i.e., the shock–bubble interactions as well as the subsequent nonlinear evolution of ablative hydrodynamic instabilities initiated by the direct interaction of the deformed defect and ablation front, revealing that compressibility and baroclinic effects drive vorticity production during the interactions between the shock wave and the isolated defect. In the “light-bubble” case, the vortex pair generated in the first process is further strengthened by the laser ablation. Hence, a directed flow is formed in companion with the persistent flow entering the bubble of the surrounding ablator. The bubble exhibits a remarkable growth both laterally and deeply, seriously threatening the shell's integrity. The positive feedback mechanism of the vortex pair is absent in the “heavy-bubble” counterpart, and the ablation stabilization manifested itself in the reduction of spike amplitude. A systematic study of localized perturbation growth as a function of defect placement, size, and preheating intensity is presented.

The influence of thin-shell effects on the nonlinear evolution of two-dimensional single-mode ablative Rayleigh–Taylor instability (ARTI) is studied in the parameter range of inertial confinement fusion implosions. A new phase of unsaturated nonlinear bubble evolution caused by thin-shell effects is found. This is different from the traditional opinion that the bubble velocity becomes saturated after the ARTI evolution enters a highly nonlinear regime. A modified bubble velocity formula is proposed, based on the Betti–Sanz model [Betti and Sanz, Phys. Rev. Lett. 97, 205002 (2006)], considering the thin-shell effects. It is shown that the bubble velocity becomes saturated in the thick-target case after the ARTI evolution enters a highly nonlinear regime. In this case, the Betti–Sanz bubble dynamics model can predict the evolution of bubble velocity. However, when the thin-shell effects become significant in the case of [Formula: see text] < 100, where [Formula: see text] is the initial thickness of the target and k is the perturbation wavenumber, the difference of the average acceleration between the bubble vertex and the spike tip can be much more significant than that of the thick-target case. In this situation, the nonlinear evolution of the ARTI bubbles will accelerate without saturation until the target breakup, which cannot be depicted by the Betti–Sanz model while the improved theory formula is applicative. The Betti–Sanz model and the improved theory formula are independent of the initial perturbation amplitude.

A weakly nonlinear (WN) theoretical model for the two-dimensional incompressible Kelvin–Helmholtz instability (KHI) is proposed. Its solution form is the complete expansion in real space. The transition from linear to nonlinear growth is analytically studied via third-order solutions of plane KHI initiated by a single-mode surface perturbation. The difference between the WN growth of the Rayleigh–Taylor instability (RTI) in plane geometry and the WN growth of the KHI in plane geometry is discussed. It is found that there are resonance solutions in the higher harmonics of KHI but not in RTI. The vertex of spikes and bubbles is deflected because of the shearing effect in KHI compared with that in RTI. The spike velocity increases with the Atwood number before a particular time and then inversely after that time. There is no such reversal in RTI. However, the bubble velocity with the Atwood number of KHI has the same evolution rule as that of RTI. In addition to the influence of initial perturbation on the nonlinear saturation amplitude, the influence of Atwood number on the nonlinear saturation amplitude of the fundamental mode is obtained. Finally, compared with the numerical simulations, at the same initial conditions, the analytical solutions up to the third harmonics are well consistent with the simulated datum in the linear and weakly nonlinear stages for a widely varied Atwood number.

耳鸣严重影响患者的生活质量，目前认为其产生机制与听觉通路信号改变所引起的神经元可塑性变化有关，其中可能涉及神经元兴奋性和抑制性传导失衡。A型γ-氨基丁酸受体（γ-aminobutyric acid a receptor,GABA(A)R）和N-甲基-D天冬氨酸受体（N-methyl-D-aspartic acid receptor,NMDAR）是重要的神经元抑制性和兴奋性受体，NMDAR功能亢进和GABA(A)R功能抑制可能是耳鸣发生中的关键性事件。钙/钙调蛋白激酶Ⅱ(Ca(2+)/calmodulin-dependent protein kinaseⅡ,Ca(2+)/CaMKⅡ）是一种丝氨酸/苏氨酸蛋白激酶，介导NMDAR和GABA(A)R的磷酸化及其相互作用，在神经突触受体活性调节过程中发挥重要作用，并可能参与耳鸣的发生发展过程。本文就Ca(2+)/CaMKⅡ介导NMDAR与GABA(A)R的相互作用及其与耳鸣的关系展开综述，并结合临床试验介绍相关耳鸣治疗最新研究成果，以期为临床耳鸣的治疗提供新的作用靶点和干预思路。.

The high-temperature flow behavior of an aerospace structural material Al-0.62 Mg-0.73Si aluminum alloy was researched in this work. The isothermal compression tests were carried out in the temperature range of 683-783 K and strain rate range of 0.001-1 s−1. Based on the obtained true stress-true strain curves, the constitutive relationship of the alloy was revealed by establishing the Arrhenius-type constitutive model and a modified Johnson-Cook model. It was found that the flow characteristics were closely related to deformation temperature and strain rate. The activation energy of the studied material was calculated to be approximately 174 kJ mol−1. A comparative study has been conducted on the accuracy and reliability of the proposed models using statistics analysis method. It was proved by error analysis that the Arrhenius-type model had a better performance than the modified Johnson-Cook model.

To investigate the expression of annexin A7 (ANXA7) in the differentiation and lymphatic metastasis of gastric cancer (GC), and to investigate the relationship between ANXA7 and biological characteristics of GC.The clinicopathological data of 124 patients with gastric cancer who underwent surgical treatment in our hospital were retrospectively reviewed and analyzed. Immunohistochemical staining and Western blot were performed to analyze the expression of ANXA 7 in primary GC tissues. Logistic regression analysis was conducted to evaluate the association between ANXA7 expression level and differentiation of the GC.A total of 124 GC patients were enrolled in this study, and the expression rate of ANXA7 was 65.3% in the GC. The survival rate of ANXA7-positive patients was significantly lower than that in the patients with negative expression (P0.001). The results of Cox regression analysis showed that the positive expression of ANXA7, submucosal confinement and pathological stage of GC were associated with poor clinical outcomes. The ratio of pixel density value of primary GC tissues with lymph node metastasis was significantly higher than those in the tissues without lymph node metastasis (0.51±0.07 vs. 0.39±0.06, P0.001). ROC analysis showed a high area under the curve for the ratio of pixel density value of annexin A7 in the primary GC tissues. At a cut-off level of0.419, the ratio of pixel density value of ANXA7 exhibited a sensitivity of 91.2% and a specificity of 72.7% for detecting lymph node metastasis of GC.High annexin A7 expression is associated with poor differentiation of gastric cancer, and it may become a predictor for lymphatic metastasis of GC.

Experimental studies are presented on drying of soybean milk in a vibrated fluidized bed of inert particles. The effects of inlet air temperature, superficial air velocity, static bed height, and the feed rate on the bed pressure drop, product hold-up and the convective heat transfer coefficient are discussed. The thermal efficiency of the dryer as well as some basic characteristics for the vibrated fluid bed of glass beads and Teflon pellets are given and compared to the ones for conventional fluid beds. A regression equation for the volumetric heat transfer coefficient is provided.

While progress towards hot-spot ignition has been made achieving an alpha-heating dominated state in high-foot implosion experiments [Hurricane et al., Nat. Phys. 12, 800 (2016)] on the National Ignition Facility, improvements are needed to increase the fuel compression for the enhancement of the neutron yield. A strategy is proposed to improve the fuel compression through the recompression of a shock/compression wave generated by the end of the main drive portion of a high-foot pulse shape. Two methods for the peak pulse recompression, namely, the decompression-and-recompression (DR) and simple recompression schemes, are investigated and compared. Radiation hydrodynamic simulations confirm that the peak pulse recompression can clearly improve fuel compression without significantly compromising the implosion stability. In particular, when the convergent DR shock is tuned to encounter the divergent shock from the capsule center at a suitable position, not only the neutron yield but also the stability of stagnating hot-spot can be noticeably improved, compared to the conventional high-foot implosions [Hurricane et al., Phys. Plasmas 21, 056314 (2014)].

It is demonstrated that the growth of acceleration-phase instabilities in inertial confinement fusion implosions can be controlled, especially in the high-foot implosions [O. A. Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility. However, the excessive growth of the deceleration-phase instabilities can still destroy the hot spot ignition. A scheme is proposed to retard the deceleration-phase Rayleigh–Taylor instability growth by shock collision near the waist of the inner shell surface. Two-dimensional radiation hydrodynamic simulations confirm the improved deceleration-phase hot spot stability properties without sacrificing the fuel compression.

The evolution of the ablative Rayleigh-Taylor instability in the presence of preheating of the cold pristine plasma ahead of the ablative front is investigated by two-dimensional numerical simulation. When the dependence of the linear ARTI growth rate on the excitation wavelength has a sharp maximum, a secondary spike-bubble structure at a harmonic of the excitation wavelength will be generated, leading to rupture of the original mode. On the other hand, for stronger preheating the linear growth rate has no sharp maximum and in the nonlinear evolution no competing secondary spike-bubble structure is generated. Instead, the original excitation evolves into an elongated jet. These results are in agreement with that from an analytical single-mode theory.

By using the arrhythmic animal models, the effect of 6,7-dimethoxycoumarin (DMOC) on arrhythmia was investigated. The arrhythmia in anaesthetized rat were induced by iv aconitine 20 micrograms.kg-1 or CaCl2 5 mg.kg-1. The arrhythmia in anesthetized guinea pigs was induced by iv ouabain 3.6 micrograms.kg-1.min-1. Procainamide (PA) was used as a positive control. DMOC (33-500 mg.kg-1, ig) and PA (100-800 mg.kg-1, ig) in anaesthetized rats could delay the time of onset of arrhythmia induced by aconitine. The ED50 of DMOC and PA for postponing the occurrence of ventricular extrasystole (VE) were 88 mg.kg-1 (95% confidence interval was 43-165 mg.kg-1) and 183 mg.kg-1 (95% confidence interval was 109-304 mg.kg-1), respectively. The results suggested that the anti-arrhythmia potency of DMOC was higher than that of PA (P0.01).

The in vitro effects of polyglycosides of Tripterygium wilfordii Hook (T II) on immunoglobulin (Ig) production by peripheral blood mononuclear cells (PB-MC) from seventeen healthy persons and eight rheumatoid arthritis (RA) patients were studied. PBMCs, monocytes and lymphocytes were treated separately with different doses of T II for different periods of time. Cells in different combinations were cultured for two weeks under pokeweed mitogen (PWM) stimulation and the IgG and IgM content of culture supernatants were determined using the double antibody solid-phase immunoradiometric assay. There was no difference in the inhibitory effect of T II on in vitro IgM and IgG production by PB-MCs either between the two types of Ig or between healthy individuals and RA patients. T II acts both on monocytes and lymphocytes, but more strongly on the latter. This observation appears to differ from the reported actions of gold and penicillamine. The results obtained in this study correlate well with those of clinical trials, suggesting that the therapeutic effect of T II is associated with its immunosuppressive activity.