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Current-induced spin torques provide efficient data writing approaches for magnetic memories. Recently, the spin splitting torque (SST) was theoretically predicted (R. Gonz\'alez-Hern\'andez et al. Phys. Rev. Lett. 126, 127701 (2021)), which combines advantages of conventional spin transfer torque (STT) and spin-orbit torque (SOT) as well as enables controllable spin polarization. Here we provide the experimental evidence of SST in collinear antiferromagnet RuO2 films. The spin current direction is found to be correlated to the crystal orientation of RuO2 and the spin polarization direction is dependent on (parallel to) the N\'eel vector. These features are quite characteristic for the predicted SST. Our finding not only present a new member for the spin torques besides traditional STT and SOT, but also proposes a promising spin source RuO2 for spintronics., Comment: 18 pages, 4 figures, accepted by Phys. Rev. Lett

The present study is motivated by the shock response of a nano-cantilever component in nano-scaled electromechanical system (NEMS). For this purpose, the mechanical properties of a cantilevered nano-beams subjected to impact load are presented for the first time. Our work is concerned with the special moment that the impact deformation gets most and the impact velocity reduces to zero. The nonlocal theory proposed by Eringen is applied to reveal the nonlocal effect involved in impact behaviors at nano-scale. To this end, the classical impact stress is determined first using the law of conservation of energy. Subsequently, the nonlocal impact stress is obtained from the nonlocal constitutive equation and clamped-free boundary constraints of cantilevered nano-beams, where an imaginary equivalent symmetrical nano-structure is constructed to solve the unknown coefficients in general solution of stress of nonlocal field. The bending moment in nonlocal theory is gained from the stress of nonlocal field and the deflection in nonlocal field under impact load is calculated. Finally, the nonlocal dynamical load coefficient is derived via the maximal nonlocal impact deflection divided by the corresponding traditional static deflection at free edge. In numerical examples, the maximal stress of nonlocal field, the maximal nonlocal impact deflection, and the nonlocal dynamical load coefficient are calculated, respectively, to show the significant nonlocal small-scale effect in cantilevered nano-beams subjected to impact load. The conclusion is that the nonlocality plays a remarkable role in nano-scaled impact behaviors and it cannot be neglected. The existence of scale coefficient decreases the nonlocal impact stress, deflection, and dynamical load coefficient. On the contrary, the impact velocity results in a higher nonlocal impact stress, deflection, and dynamical load coefficient. With increasing the scale coefficient, the nonlocal effect increases and the strengthening physical manifestation of nano-structural equivalent stiffness becomes even more pronounced. The results reported herein are expected to provide a useful reference for understanding the scale effect in dynamic impact that often occurs in the working process of NEMS.

Bi(1+x)Fe0.95Mn0.05O3 thin films with different bismuth contents (abbreviated as B1+xFMO, x = − 0.05, 0, 0.05, 0.1) were fabricated by chemical solution deposition on ITO/glass substrates. The effects of Bi nonstoichiometry on the microstructure, leakage current, ferroelectric and dielectric properties of BFMO films are investigated. The B1.05FMO and B1.1FMO thin films possess single perovskite structure, while the secondary phase of Bi2Fe4O9 can be observed in BFMO and B0.95FMO thin films. Compared with the other three samples in this work, drastically reduced leakage current can be found in B1.05FMO. For each film, the dominant conduction mechanisms are the Ohmic conduction and the space charge limited conduction at lower electric fields and the interface-limited Fowler–Nordheim tunneling at higher electric regions, respectively. Among the B1+xFMO films (x = − 0.05, 0, 0.05, 0.1), the B1.05FMO film possesses significantly improved electrical properties, reflected by a large remanent polarization (Pr ~ 68.3 µC/cm2), lower dielectric loss (tanδ ~ 0.02), large dielectric constant (er ~ 210) and high tunability (88%). These results suggest that the 5 mol% excess of Bi is the prior content to get better insulation, optimize ferroelectric as well as dielectric properties of BiFeO3 film, giving reference to modify electrical performances of ferroelectric materials through regulation of volatile element.

Additional file 1. Revised supporting information.

Two-dimensional (2D) ferromagnetic (FM) semiconductors are highly desirable in next generation spintronic devices. Herein, we report an intrinsic FM semiconductor, an FeI3 monolayer which can be exfoliated from its bulk crystal owing to the small cleavage energy and the high in-plane stiffness. The FeI3 monolayer is dynamically and mechanically stable. Additionally, the FeI3 monolayer has sizable magneto-crystalline anisotropy energy (MAE) and the Curie temperature is higher than the liquid-nitrogen temperature (77 K), and there is a big discrepancy (Δcbm) between the conduction band minimum of the two spin-channels and negligible thermally induced hop. Carrier doping less than 0.1 e per unit cell further improves the relevant properties by modulating the MAE, Curie temperature, and Δcbm. Moreover, the isoelectronic analogue FeI1.5Cl1.5 monolayer is a bipolar FM semiconductor with a high Curie temperature (260 K). Our results demonstrate promising applications of the FeI3 monolayer in next-generation spintronic devices owing to its robust intrinsic ferromagnetism and novel semiconducting properties.

Increasing evidence indicated that N6-methyl-adenosine (M6A) played a key role in a variety of pathophysiological processes. Methylases could promote the processing of mature mi-RNA in a M6A-dependent manner, thereby participating in the pathological cells' occurrence and development. However, the regulatory mechanism of M6A in atherosclerosis (AS) was still unclear.Quantificational Real-time polymerase chain reaction (qRT-PCR) was used to detect the relative expression levels of M6A, methyltransferase, demethylase transferase, miR-19a and other mi-RNA in atherosclerotic vascular endothelial cells (ASVEC). Cell Counting Kit (CCK8) was used to detect cell proliferation, the expression of PCNA was measured by Western Blot (WB) and qRT-PCR. Transwell assays were used to detect the invasion ability of ASVEC. Co-immunoprecipitation (Co-IP) was used to detect the binding of METTL14 to DGCR8. RNA Immunoprecipitation (RIP) was used to detect the binding of METTL14 to miR-19a.M6A modification levels and METTL14 methylation transferase were significantly overexpressed in ASVEC. Silencing METTL14 inhibited the proliferation and invasion of ASVEC. Low expression of METTL14 suppressed the binding of methylated RNA and RNA splicing related protein DGCR8. Moreover, silencing METTL14 significantly inhibited the expression of miR-19a while promoted the expression of primary pre-miR-19a. However, high expression of METTL14 obviously increased the expression of DGCR8 and methylated m6A. Furthermore, silencing miR-19a inhibited the proliferation and invasion of ASVEC.METTL14 increased the M6A modification of pri-miR-19a and promoted the processing of mature miR-19a, thus promoting the proliferation and invasion of ASVEC. These results suggested that METTL14/ M6A/ miR-19a signaling pathway may be a new target for atherosclerosis treatment.

本文报道了1例因挖耳勺刺入过深导致镫骨前庭脱位的患者，女，48岁，因鼓膜穿透伤后眩晕伴恶心呕吐1 d入院，结合患者症状、体征及影像学检查诊断为外伤性镫骨前庭内脱位（左侧），予以减轻水肿及抗眩晕、止吐等对症治疗后症状完全缓解。随访3个月无异常。.