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To overcome the interfacial nature of spin‐orbit torque (SOT) in bilayers, novel bulk SOT (BSOT) is widely investigated to implement high‐density and low‐power spintronic devices. However, the underlying mechanism of efficient BSOT switching remains unclear, especially the anomalously enhanced effective spin Hall angle (θSH) with increasing ferromagnet thickness (tFM), due to lacking simple and high‐tunable material systems. Here, a series of Pt/Co multilayers with invariable thickness gradient and varying stacking numbers is designed to systematically explore BSOT origin and enable efficient switching via engineering symmetry breaking. As tFM increases, the critical current density decreases while the switching efficiency and θSH build up. Comparative experiments directly demonstrate that gradient‐induced local spin current is more efficient than that in the bilayer. Moreover, x‐ray absorption spectroscopy (XAS) results reveal that the increasing stacking number can effectively engineer the symmetry breaking at Pt/Co interface to induce strong interfacial spin‐orbit coupling. On this basis, it is concluded that the BSOT effect, as well as the anomalously enhanced switching efficiency, and θSH arises from gradient‐induced bulk and interface symmetry breaking. These findings clarify the underlying mechanism of BSOT, and broaden the scope of material engineering to improve switching efficiency and inspire more memory and computing applications. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to evaluate the clinical value and biological function of long non-coding RNA (lncRNA) LINC-P21 in type 2 diabetes mellitus (T2DM), and explore the underlying mechanisms. Methods The expression of LINC-P21 was estimated using quantitative real-time PCR. The functional role of LINC-P21 was explored by gain- and loss-of-function experiments. INS-1 cell proliferation was analyzed using a cell counting kit-8 (CCK-8)assay, and the glucose-stimulated insulin secretion was measured using an ELISA kit. The miRNAs that might be sponged by LINC-P21 were analyzed, and the subsequent target genes were predicted and assessed in INS-1 cells. Results Serum expression of LINC-P21 was elevated in T2DM patients, which was correlated with fasting blood glucose levels and disease diagnosis. The glucose-stimulated insulin secretion and the proliferation of INS-1 cells were enhanced by LINC-P21 knockdown, but the overexpression of LINC-P21 led to opposite effects. miR-766-3p could be directly inhibited by LINC-P21 in INS-1 cells and reverse the effects of LINC-P21 on β-cell function. Additionally, NR3C2 was determined as a target of miR-766-3p, which could be positively regulated by LINC-P21 and had same effects with LINC-P21 on INS-1 cell proliferation and insulin secretion. Conclusion All the data demonstrated that serum elevated LINC-P21 and decreased miR-766-3p serve as candidate diagnostic biomarkers in T2DM patients. LINC-P21 acts as a potential regulator in insulin secretion and proliferation of pancreatic β-cells through targeting miR-766-3p to upregulate NR3C2. [ABSTRACT FROM AUTHOR]

Spin–orbit torque (SOT) effect is considered as an efficient way to switch the magnetization and can inspire various high-performance spintronic devices. Recently, topological insulators (TIs) have gained extensive attention, as they are demonstrated to maintain a large effective spin Hall angle (), even at room temperature. However, molecular beam epitaxy (MBE), as a precise deposition method, is required to guarantee favorable surface states of TIs, which hinders the prospect of TIs towards industrial application. In this paper, we demonstrate that Bi2Te3 films grown by magnetron sputtering can provide a notable SOT effect in the heterostructure with perpendicular magnetic anisotropy CoTb ferrimagnetic alloy. By harmonic Hall measurement, a high SOT efficiency (8.7 ± 0.9 Oe/(109 A/m2)) and a large (3.3±0.3) are obtained at room temperature. Besides, we also observe an ultra-low critical switching current density (9.7×109 A/m2). Moreover, the low-power characteristic of the sputtered Bi2Te3 film is investigated by drawing a comparison with different sputtered SOT sources. Our work may provide an alternative to leverage chalcogenides as a realistic and efficient SOT source in future spintronic devices. [ABSTRACT FROM AUTHOR]

Spin–orbit torque (SOT) effect is considered as an efficient way to switch the magnetization and can inspire various high-performance spintronic devices. Recently, topological insulators (TIs) have gained extensive attention, as they are demonstrated to maintain a large effective spin Hall angle (), even at room temperature. However, molecular beam epitaxy (MBE), as a precise deposition method, is required to guarantee favorable surface states of TIs, which hinders the prospect of TIs towards industrial application. In this paper, we demonstrate that Bi2Te3 films grown by magnetron sputtering can provide a notable SOT effect in the heterostructure with perpendicular magnetic anisotropy CoTb ferrimagnetic alloy. By harmonic Hall measurement, a high SOT efficiency (8.7 ± 0.9 Oe/(109 A/m2)) and a large (3.3±0.3) are obtained at room temperature. Besides, we also observe an ultra-low critical switching current density (9.7×109 A/m2). Moreover, the low-power characteristic of the sputtered Bi2Te3 film is investigated by drawing a comparison with different sputtered SOT sources. Our work may provide an alternative to leverage chalcogenides as a realistic and efficient SOT source in future spintronic devices. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of dexmedetomidine on the cognitive dysfunction of aged rats after open tibia fracture surgery and the expression of inflammatory cytokines in the hippocampus., Methods: A total of 45 aged healthy male Sprague Dawley rats were divided into control group, sham group, and dexmedetomidine group. The open tibia fracture surgery rat model was established, and dexmedetomidine was intraperitoneally injected before operation. The cognitive function of aged rats was examined by Morris Water-Maze Test, open field experiment, and passive avoidance memory test. The expression levels of IL-6, IL-1β, and TNF-α in the hippocampus were examined by enzyme-linked immunosorbent assay (ELISA)., Results: The escape latency over 5 continuous days in the dexmedetomidine group was significantly shorter than that in the control group (all P<0.05). The number of swimming times and the percentage of swimming time in the dexmedetomidine group were significantly higher and longer than those in the control group (all P<0.05). Moreover, rats in the dexmedetomidine group exhibited shorter time of stay at the central square and higher number of standing times in comparison with the control group (all P<0.05). Compared with the control group, dexmedetomidine intraperitoneally injected before surgery significantly inhibited the expression levels of IL-6, IL-1β, and TNF-α in the hippocampus (all P<0.05)., Conclusion: Dexmedetomidine could significantly relieve the postoperative cognitive dysfunction in aged rats. The mechanism may be associated with the decreased inflammatory cytokines in the hippocampus., Competing Interests: None., (AJTR Copyright © 2024.)

Objective: Atherosclerosis (AS) is a chronic inflammatory disease with high mortality. miRNAs perform a vital role in its development. This study aimed to discuss the effect of miR-145 in AS occurrence and development., Methods: The effects of miR-145 mimics and inhibitors on IL-6, IL-1β and TNF-α expressions were assessed by qRT-PCR and ELISA. CCK-8 was applied to examine the influence of miR-145 on macrophage proliferation. The influence of miR-145 on the QKI transcriptional activity was analyzed using luciferase reporter gene assy., Results: Overexpression of miR-145 could enhance the expression of IL-6, IL-1β, and TNF-α. Down-regulation of miR-145 could inhibit the proliferation of macrophages and the expression level of inflammatory cytokines. The effect of miR-145 inhibitor on the expression of inflammatory factors was partially reversed by interfering with the transcription of QKI with siRNA., Conclusion: miR-145 regulates the inflammatory response induced by macrophage activation through targeting QKI. It provides a means for AS targeted therapy., Competing Interests: None., (AJTR Copyright © 2022.)