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Typical Al-Ti-B master alloys are good inoculant for aluminum alloys, which have shown obvious dependence on some alloying elements. In this work, in situ AlN-TiN-TiB2/Al composite refiner was successfully prepared by nitrogen alloying based on an Al-8Ti-1B melt. It is found that the refining, tensile strength, yield strength, and hardness of the pure aluminum modified by in situ AlN-TiN-TiB2/Al composite inoculant were all obviously improved. The enhanced refining and reinforcing effects of the refiner can be attributed to the following aspects: the formation of AlN and TiN particles, the homogeneous distribution of AlN, TiN, and TiB2 particles and the miniaturization of Al3Ti phases. The above three factors are all caused by nitridation and have a combining effect for improving the nucleation rate of α-Al. [ABSTRACT FROM AUTHOR]

microRNAs (miRNAs) regulate gene expression at the post-transcriptional level and play important roles in tumor initiation and progression. Recently, we examined the global miRNA expression profile of esophageal squamous cell carcinoma (ESCC) and demonstrated that miR-92a was highly expressed in tumor tissues. In this study, we found that the upregulation of miR-92a was significantly correlated with the status of lymph node metastasis and TNM stage in 107 ESCC patients. Moreover, the upregulation of miR-92a was associated with poor survival of ESCC patients and might be used as an independent prognostic factor. Next, we investigated the role and mechanism of miR-92a in ESCC cells, and found that miR-92a modulated the migration and invasion but not apoptosis and proliferation of ESCC cells in vitro. We further demonstrated that miR-92a directly targeted the CDH1 3′- UTR and repressed the expression of CDH1, a tumor metastasis suppressor. In addition, restoring of miR-92a-resistant CDH1 expression in miR-92a-overexpression cells recovered the pro-metastasis activity of miR-92a. Taken together, we demonstrated that miR-92a promotes ESCC cell migration and invasion at least partially via suppression of CDH1 expression, and patients with up-regulated miR-92a are prone to lymph node metastasis and thus have poor prognosis. [ABSTRACT FROM AUTHOR]

We present the exact analytical solution of stripe solitons on different backgrounds in Bose–Einstein condensates with helicoidal spin–orbit coupling (SOC). They are divided into two categories, one is stationary stripe soliton on zero background or period-wave background, the other is moving stripe soliton on zero background or plane-wave background. The period of stripe is determined by both strength and frequency of helicoidal SOC, and the oscillation amplitude of stripe is adjustable in the case of fixed total density. The corresponding spin polarization is expressed on Bloch sphere. For stationary soliton, the spin density vector take values in three directions, which is different from the Rashba–Dresslhaus coupling scheme. The spin density vectors display more complicated spatial distribution for moving stripe solitons. Meanwhile, the formation mechanism of stripe soliton and the interaction properties of moving stripe solitons are discussed. Our work enhances the understanding of stripe solitons, and is helpful for the observation of stripe phase. • Four kinds of exact stripe soliton solutions in Bose–Einstein condensates with helicoidal spin–orbit coupling (SOC) are represented. • The influence of helicoidal SOC on the structure of stripe solitons are described in detail. • The corresponding spin polarization is expressed on the Bloch sphere. • The formation mechanism of stripe solitons and the interaction properties of moving stripe solitons are discussed. [ABSTRACT FROM AUTHOR]

Exact analytical soliton solutions play an important role in soliton fields. Soliton solutions were obtained with some special constraints on the nonlinear parameters in nonlinear coupled systems, but they usually do not hold in real physical systems. We successfully release all usual constrain conditions on nonlinear parameters for exact analytical vector soliton solutions in N-component coupled nonlinear Schrödinger equations. The exact soliton solutions and their existence condition are given explicitly. Applications of these results are discussed in several present experimental parameter regimes. The results would motivate experiments to observe more novel vector solitons in nonlinear optical fibers, Bose-Einstein condensates, and other nonlinear coupled systems.

Dark soliton is usually seen as one of the simplest topological solitons, due to phase shift across its intensity dip. We investigate phase characters of single-valley dark soliton (SVDS) and double-valley dark soliton (DVDS) in a single-mode optical fiber with third-order dispersion and delayed nonlinear response. Notably, two different phase shifts can produce an SVDS with the same velocity under some conditions, which is not admitted for a dark soliton with only the second-order dispersion and self-phase modulation, whose phase shift and velocity is a one-to-one match. This phase property of SVDS can be used to explain the generation of previously reported DVDS in Hirota equation and make DVDSs show two types of phase profiles. Moreover, the different topological vector potentials underlying the distinct phase profiles have been uncovered. We further explore the collision properties of the DVDSs by analyzing their topological phases. Strikingly, the inelastic collision can lead to the conversion between the two types of phase profiles for DVDS. The results reveal that inelastic or elastic collision can be judged by analyzing virtual topological magnetic fields.

Weak Gaussian perturbations on a plane wave background could trigger lots of rogue waves (RWs), due to modulational instability. Numerical simulations showed that these RWs seemed to have similar unit structure. However, to the best of our knowledge, there are no relative results to prove that these RWs have the similar patterns for different perturbations, partly due to that it is hard to measure the RW pattern automatically. In this work, we address these problems from the perspective of computer vision via using deep neural networks. We propose a rogue wave detection network (RWD-Net) model to automatically and accurately detect RWs in the images, which directly indicates they have the similar computer vision patterns. For this purpose, we herein meanwhile have designed and release the corresponding dataset, termed as rogue wave dataset-10K (RWD-10K), which has 10191 RW images with bounding box annotations for each RW unit. In our detection experiments, we get 99.29% average precision on the test splits of the proposed dataset. Finally, we derive our metric, termed as the density of RW units, to characterize the evolution of Gaussian perturbations and obtain the statistical results on them.

We study numerically the evolutions of perturbations at critical points between modulational instability and stability regimes. It is demonstrated that W-shaped solitons and rogue waves can be both excited from weak resonant perturbations at the critical points. The rogue wave excitation at the critical points indicates that rogue wave comes from modulation instability with resonant perturbations, even when the baseband modulational instability is absent. The perturbation differences for generating W-shaped solitons and rogue waves are discussed in detail. These results can be used to generate W-shaped solitons and rogue waves controllably from weak perturbations.

Objective: To evaluate the predictive value of Type D personality on in-stent restenosis (ISR) rates at 1 and 2 years post-percutaneous coronary intervention (PCI) in patients with coronary artery disease., Methods: Consecutive patients with coronary artery disease who underwent PCI for drug-eluting stents (n = 173) completed the Type D Scale-14 (DS14) at baseline. Follow-up coronary angiographic evaluation was routinely planned at 1 and 2 years after the procedure., Results: Follow-up coronary angiography was performed in 159 and 112 patients at 1 and 2 years post-PCI, respectively. On multivariate analysis, Type D personality was found to be an independent predictor of ISR at 1 year (odds ratio [OR] = 2.67, 95% confidence interval [CI] = 1.16-6.14, p = .021) and 2 years (OR = 4.92, 95% CI = 1.82-9.60, p = .017) after adjusting for cardiovascular risk factors. However, Type D did not predict ISR when the analysis was performed using the interaction between negative affectivity and social inhibition. The main effect of negative affectivity emerged as a significant risk factor for 1-years (OR = 4.22, 95% CI = 1.18-7.86, p = .034) and 2-year ISR (OR = 6.93, 95% CI = 2.25-11.50, p = .016)., Conclusions: In this study, Type D personality was an independent predictor of ISR at 1 and 2 years post-PCI; the association strengthened with time. The negative affectivity component seems to drive the relationship between Type D and ISR over time. Our findings provide new insights into the mechanisms involved in the association between Type D and adverse clinical outcomes of PCI.

We investigate linear interference effects between a nonlinear plane wave and bright solitons, which are admitted by a pair-transition coupled two-component Bose-Einstein condensate. We demonstrate that the interference effects can induce several localized waves possessing distinctive wave structures, mainly including anti-dark solitons, W-shaped solitons, multi-peak solitons, Kuznetsov-Ma like breathers, and multi-peak breathers. Specifically, the explicit conditions for them are clarified by a phase diagram based on the linear interference properties. Furthermore, the interactions between these localized waves are discussed. The detailed analysis indicates that the soliton-soliton interaction induced phase shift brings the collision between these localized waves which can be inelastic for solitons involving collision and can be elastic for breathers. These characters come from the fact that the profile of solitons depends on the relative phase between bright solitons and a plane wave, and the profile of breathers does not depend on the relative phase. These results would motivate more discussions on linear interference between other nonlinear waves. Specifically, the solitons or breathers obtained here are not related to modulational instability. The underlying reasons are discussed in detail. In addition, possibilities to observe these localized waves are discussed in a two species Bose-Einstein condensate.