Influence of stirring speed on SiC particles distribution in A356 liquid

A straight-blade mechanical stirrer was designed to stir A356-3.5vol%SiCp liquid in a cylindrical crucible with the capability of systematically investigating the influence of rotating speed of stirrer on the distribution of SiC particles in A356 liquid. The experimental results show that the vertical distribution of SiC particles in A356 liquid can be uniform when the rotating speed of stirrer is 200 rpm, but the radial distribution of SiC particles in A356 liquid is always nonhomogeneous regardless of the rotating speed of stirrer. The radial centrifugalization ratio of SiC particles in A356 liquid between the center and the periphery of crucible increases with the rotating speed of stirrer. The results were explained in the light of SiC particles motion subject to a combination of stirring and centrifugal effect

Steady Bell state generation via magnon-photon coupling

We show that parity-time ($\mathcal{PT}$) symmetry can be spontaneously broken in the recently reported energy level attraction of magnons and cavity photons. In the $\mathcal{PT}$-broken phase, magnon and photon form a high-fidelity Bell state with maximum entanglement. This entanglement is steady and robust against the perturbation of environment, in contrast to the general wisdom that expects instability of the hybridized state when the symmetry is broken. This anomaly is further understood by the compete of non-Hermitian evolution and particle number conservation of the hybridized system. As a comparison, neither $\mathcal{PT}$-symmetry broken nor steady magnon-photon entanglement is observed inside the normal level repulsion case. Our results may open a novel window to utilize magnon-photon entanglement as a resource for quantum technologies.Comment: 5 pages, 4 figure

Propensity score regression for causal inference with treatment heterogeneity

Understanding how treatment effects vary on individual characteristics is critical in the contexts of personalized medicine, personalized advertising and policy design. When the characteristics are of practical interest are only a subset of full covariate, non-parametric estimation is often desirable; but few methods are available due to the computational difficult. Existing non-parametric methods such as the inverse probability weighting methods have limitations that hinder their use in many practical settings where the values of propensity scores are close to 0 or 1. We propose the propensity score regression (PSR) that allows the non-parametric estimation of the heterogeneous treatment effects in a wide context. PSR includes two non-parametric regressions in turn, where it first regresses on the propensity scores together with the characteristics of interest, to obtain an intermediate estimate; and then, regress the intermediate estimates on the characteristics of interest only. By including propensity scores as regressors in the non-parametric manner, PSR is capable of substantially easing the computational difficulty while remain (locally) insensitive to any value of propensity scores. We present several appealing properties of PSR, including the consistency and asymptotical normality, and in particular the existence of an explicit variance estimator, from which the analytical behaviour of PSR and its precision can be assessed. Simulation studies indicate that PSR outperform existing methods in varying settings with extreme values of propensity scores. We apply our method to the national 2009 flu survey (NHFS) data to investigate the effects of seasonal influenza vaccination and having paid sick leave across different age groups

Acoustic transmission enhancement through a periodically-structured stiff plate without any opening

We report both experimentally and theoretically that the enhanced acoustic transmission can occur in the subwavelength region through a thin but stiff structured-plate without any opening. This exotic acoustic phenomenon is essentially distinct from the previous related studies originated from, either collectively or individually, the interaction of the incident wave with openings in previous structures. It is attributed to the structure-induced resonant excitation of the non-leaky Lamb modes that exist intrinsically in the uniform elastic plate. Our finding should have impact on ultrasonic applications.Comment: 11 pages, 4 figure

Accelerating 3-D GPU-based Motion Tracking for Ultrasound Strain Elastography Using Sum-Tables: Analysis and Initial Results.

Now, with the availability of 3-D ultrasound data, a lot of research efforts are being devoted to developing 3-D ultrasound strain elastography (USE) systems. Because 3-D motion tracking, a core component in any 3-D USE system, is computationally intensive, a lot of efforts are under way to accelerate 3-D motion tracking. In the literature, the concept of Sum-Table has been used in a serial computing environment to reduce the burden of computing signal correlation, which is the single most computationally intensive component in 3-D motion tracking. In this study, parallel programming using graphics processing units (GPU) is used in conjunction with the concept of Sum-Table to improve the computational efficiency of 3-D motion tracking. To our knowledge, sum-tables have not been used in a GPU environment for 3-D motion tracking. Our main objective here is to investigate the feasibility of using sum-table-based normalized correlation coefficient (ST-NCC) method for the above-mentioned GPU-accelerated 3-D USE. More specifically, two different implementations of ST-NCC methods proposed by Lewis et al. and Luo-Konofagou are compared against each other. During the performance comparison, the conventional method for calculating the normalized correlation coefficient (NCC) was used as the baseline. All three methods were implemented using compute unified device architecture (CUDA; Version 9.0, Nvidia Inc., CA, USA) and tested on a professional GeForce GTX TITAN X card (Nvidia Inc., CA, USA). Using 3-D ultrasound data acquired during a tissue-mimicking phantom experiment, both displacement tracking accuracy and computational efficiency were evaluated for the above-mentioned three different methods. Based on data investigated, we found that under the GPU platform, Lou-Konofaguo method can still improve the computational efficiency (17-46%), as compared to the classic NCC method implemented into the same GPU platform. However, the Lewis method does not improve the computational efficiency in some configuration or improves the computational efficiency at a lower rate (7-23%) under the GPU parallel computing environment. Comparable displacement tracking accuracy was obtained by both methods

Tutorial: Nonlinear magnonics

Nonlinear magnonics studies the nonlinear interaction between magnons and other physical platforms (phonon, photon, qubit, spin texture) to generate novel magnon states for information processing. In this tutorial, we first introduce the nonlinear interactions of magnons in pure magnetic systems and hybrid magnon-phonon and magnon-photon systems. Then we show how these nonlinear interactions can generate exotic magnonic phenomena. In the classical regime, we will cover the parametric excitation of magnons, bistability and multistability, and the magnonic frequency comb. In the quantum regime, we will discuss the single magnon state, Schr\"{o}dinger cat state and the entanglement and quantum steering among magnons, photons and phonons. The applications of the hybrid magnonics systems in quantum transducer and sensing will also be presented. Finally, we outlook the future development direction of nonlinear magnonics.Comment: 50 pages, 26 figure

lncRNA ANCR regulating the effects of miR-497-5p on vascular lumen formation and apoptosis of gastric cancer cells

Objective To explore the effects of lncRNA ANCR regulating miR-497-5p on vascular lumen formation, apoptosis and PI3K/AKT signaling pathway of gastric cancer cells. Methods Gastric cancer cells were collected and divided into gastric cancer cell (GC) group, gastric cancer cell +lncRNA ANCR-NC (AN) group, gastric cancer cell + lncRNA ANCR overexpressed plasmid (AM) group, gastric cancer cell + lncRNA ANCR siRNA (AI) group, gastric cancer cells + miR-497-5p-NC (MN) group, gastric cancer cells + miR-497-5p siRNA (MI) group, gastric cancer cells +miR-497-5p mimics (MM) group, and gastric cancer cells + lncRNA ANCR siRNA+miR-497-5p mimics (IM) group. Vascular lumen formation was observed by lumen formation assay, cell apoptosis was detected by PI staining method, and protein expression of PI3K and AKT was detected by western blotting. The interaction between lncRNA ANCR and miR-497-5p was confirmed by double luciferase reporting assay. Results Compared with AN group and MN group, the apoptosis rate of AM group and MI group was significantly decreased (P＜0.05), the number of vascular lumen formation and the expression of PI3K and AKT protein were significantly increased (P＜0.05). Compared with AM and MI groups, the apoptosis rate of AI and MM groups was significantly increased (P＜0.05), while the number of vascular lumen formation and the expression of PI3K and AKT protein were significantly decreased (P＜0.05). Compared with AI and MM groups, the apoptosis rate of IM group was significantly increased (P＜0.05), the number of vascular lumen formation and the expression of PI3K and AKT protein were significantly decreased (P＜0.05). The results of double luciferase report showed that transfection of lncRNA ANCR could significantly reduce the luciferase activity of miR-497-5p-3′-UTR-WT (P＜0.05), but had no significant effect on mutant genes (P＞0.05). Conclusion Inhibition of lncRNA ANCR can effectively inhibit the formation of vascular lumen, promote cell apoptosis, and inhibit the expression of PI3K/AKT signaling pathway in gastric cancer cells, which may be related to the targeted activation of miR-497-5p