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Dynamics of tungsten wire-array Z-pinch implosions driven by a current of 3 MA has been studied on the Angara-5-1 facility by using a UV laser probe developed in the Institute of Nuclear Physics and Chemistry. The single-wire-array results including implosion trajectory, an implosion velocity of 3.7 X [10.sup.7] cm/s, and a minimum pinch size of no more than 0.9 mm were obtained. The numerical analysis indicates that the measured trajectory, velocity, and minimum pinch size were of the plasma with electron density of the order of 2 x [10.sup.20] [cm.sup.-3]. Index Terms--Implosion dynamics, UV laser probing, wire-array plasmas.

In this paper, the tension-tension fatigue behavior of unidirectional SiC/Si 3 N 4 ceramic-matrix composite with strong and weak interface bonding at room temperature has been investigated using a micromechanical approach. The hysteresis loops models considering different interface slip cases have been developed to establish the relationships between fatigue hysteresis loops, hysteresis dissipated energy, hysteresis modulus, and the interface shear stress. The damage evolution process under tension-tension fatigue loading has been analyzed using hysteresis loops. By comparing experimental fatigue hysteresis dissipated energy with theoretical computational values, the interface shear stresses of SiC/Si 3 N 4 composite with weak and strong interface bonding were obtained for different cycle numbers. The fatigue life S‒N curves and broken fibers fraction versus cycle number curves corresponding to different fatigue peak stresses have been predicted. For SiC/Si 3 N 4 with strong interface bonding, the fatigue limit stress approaches to 75% tensile strength, which is much higher than that of composite with weak interface bonding, i.e., 58% tensile strength, due to the higher interface shear stress degradation rate for weak bonding interface. [ABSTRACT FROM AUTHOR]

Abstract: Si films with <111> preferred orientation have been prepared on 6H–SiC(000−1) C-face. HRTEM and SAED results indicate that the Si film has epitaxial connection with the 6H–SiC substrate and the parallel-plane relationship of the Si/6H–SiC heterostructure is (111)Si//(000−1)6H–SiC. Using fast Fourier transform and Fourier mask filtering technique, misfit dislocations are clearly observed at the Si/6H–SiC interface, which accommodate the most of lattice mismatch strain. Every four Si (111) lattice planes are registered with five 6H–SiC(000−1) lattice planes along the interface. Based on the 4:5 lattice matching mode, the lattice structure of the Si/6H–SiC interface and its stability were energetically investigated by molecular dynamics simulations. When the Si films grow preferentially along <111> orientation on 6H–SiC(000−1) C-face, the misfit strain in Si layer significantly reduces due to the relaxation of C atoms in SiC layer near the Si/6H–SiC interface, and thus the Si/6H–SiC heterostructure has a stable interface with a small interface formation energy of −14.24eV. [Copyright &y& Elsevier]

Abstract: Stress-induced martensitic transformation of as-sputtered and post-annealed Ti50.1Ni40.8Cu9.1 thin films was investigated using in-situ synchrotron X-ray diffraction (S-XRD) technique. For the as-deposited film, in-situ S-XRD analysis showed a martensitic transformation from parent phase to martensite during initial loading, followed by reorientation of martensite variants via detwinning. This detwinning process induced a strong 〈020〉 fiber texture along the loading direction and a strong 〈002〉 fiber texture perpendicular to the loading direction. For the 650°C annealed film, there is only elastic deformation, followed by a martensitic transformation during deformation. [Copyright &y& Elsevier]

Abstract: In the present study, we examined changes in the firing rate and firing pattern of putative slow-spiking (SS) and fast-spiking (FS) interneurons in medial prefrontal cortex (mPFC) and the effect of 5-hydroxytryptamine-3 (5-HT3) receptor agonist SR 57227A on the neuronal firing in rats with 6-hydroxydopamine lesions of the substantia nigra pars compacta (SNc) by using extracellular recording. The lesion of the SNc in rats decreased the firing rate of FS interneurons and the firing pattern of both SS and FS interneurons changed towards a more burst-firing. Systemic administration of SR 57227A (40–640 μg/kg, i.v.) increased the firing rate of SS interneurons, and decreased FS interneurons in sham-operated and the lesioned rats, respectively. The doses producing excitation or inhibition in the lesioned rats were higher than sham-operated rats. The local application of SR 57227A (0.01 μg) in mPFC excited SS interneurons, and inhibited FS interneurons in sham-operated rats, while having no effects on firing rate in the lesioned rats. Systemic administration of GABAA receptor antagonist bicuculline (2 mg/kg, i.v.) excited FS interneurons in sham-operated rats, whereas bicuculline did not change the activity of FS interneurons in the lesioned rats. Our findings indicate that the putative SS and FS interneurons activity is modulated through activation of 5-HT3 receptor by direct or indirect action, and the lesion of the SNc leads to changes in firing activity of the SS and FS interneurons and decreased response of these interneurons to SR 57227A, suggesting dysfunction and/or down-regulation of 5-HT3 receptor on interneurons in the 6-hydroxydopamine-lesioned rats. [ABSTRACT FROM AUTHOR]

Background: The risk/benefit tradeoff of dual antiplatelet therapy after percutaneous coronary intervention may vary in East Asian patients as compared with their non-East Asian counterparts., Methods: The double-blind, placebo-controlled, randomized TWILIGHT trial (Ticagrelor With Aspirin or Alone in High-Risk Patients After Coronary Intervention) enrolled patients undergoing high-risk percutaneous coronary intervention. After 3 months of treatment with ticagrelor plus aspirin, event-free and adherent patients remained on ticagrelor and were randomly assigned to receive aspirin or placebo for 1 year. The primary end point was Bleeding Academic Research Consortium type 2, 3, or 5 bleeding; the key secondary end point was the first occurrence of death from any cause, nonfatal myocardial infarction, or nonfatal stroke., Results: Of 9006 enrolled and 7119 randomized patients in TWILIGHT, 1169 patients (13.0%) were enrolled at 27 Chinese sites in this prespecified substudy, of whom 1028 (14.4%) patients were randomized after 3 months. The incidence of the primary end point was 6.2% in the ticagrelor+aspirin group versus 3.5% in the ticagrelor+placebo group between randomization and 1 year (hazard ratio, 0.56 [95% CI, 0.31-0.99]; P =0.048). The key secondary end point occurred in 3.4% of patients in the ticagrelor+aspirin group versus 2.4% in the ticagrelor+placebo group (hazard ratio, 0.70 [95% CI, 0.33-1.46]; P =0.34). There was no interaction between the region of randomization (China versus the rest of the world) and randomized treatment assignment in terms of the primary or key secondary end points., Conclusions: Ticagrelor monotherapy significantly reduced clinically relevant bleeding without increasing ischemic events as compared with ticagrelor plus aspirin in Chinese patients undergoing high-risk percutaneous coronary intervention., Registration: URL: https://www., Clinicaltrials: gov; Unique identifier: NCT02270242.