Nonreciprocal Spin Waves Driven by Left-Hand Microwaves

It is a conventional wisdom that a left-hand microwave cannot efficiently excite the spin wave (SW) in ferromagnets, due to the constraint of angular momentum conservation. In this work, we show that the left-hand microwave can drive nonreciprocal SWs in the presence of a strong ellipticity-mismatch between the microwave and precessing magnetization. A critical frequency is predicted, at which the left-hand microwave cannot excite SWs. Away from it the SW amplitude sensitively depends on the ellipticity of left-hand microwaves, in sharp contrast to the case driven by right-hand ones. By tuning the microwave frequency, we observe a switchable SW non-reciprocity in a ferromagnetic single layer. A mode-dependent mutual demagnetizing factor is proposed to explain this finding. Our work advances the understanding of the photon-magnon conversion, and paves the way to designing diode-like functionalities in nano-scaled magnonics

Magnetic skyrmion generation by reflective spin-wave focusing

We propose a method to generate magnetic skyrmions by focusing spin waves totally reflected by a curved film edge. Based on the principle of identical magnonic path length, we derive the edge contour that is parabolic and frequency-independent. Micromagnetic simulations are performed to verify our theoretical design. It is found that under proper conditions, magnetic droplet first emerges near the focal point where the spin-wave intensity has been significantly enhanced, and then converts to magnetic skyrmion accompanied by a change of the topological charge. The phase diagram about the amplitude and frequency of the driving field for skyrmion generation is obtained. Our finding would be helpful for the designment of spintronic devices combing the advantage of skyrmionics and magnonics.Comment: 5 pages, 5 figure

Liquid gating elastomeric porous system with dynamically controllable gas/liquid transport

【Abstract】The development of membrane technology is central to fields ranging from resource harvesting to medicine, but the existing designs are unable to handle the complex sorting of multiphase substances required for many systems. Especially, the dynamic multiphase transport and separation under a steady-state applied pressure have great benefits for membrane science, but have not been realized at present. Moreover, the incorporation of precisely dynamic control with avoidance of contamination of membranes remains elusive. We show a versatile strategy for creating elastomeric microporous membrane-based systems that can finely control and dynamically modulate the sorting of a wide range of gasesandliquids underasteady-stateapplied pressure,nearlyeliminate fouling,and can be easily applied over many size scales, pressures, and environments. Experiments and theoretical calculation demonstrate the stability of our system and the tunability of the critical pressure. Dynamic transport of gas and liquid can be achieved through our gating interfacial design and the controllable pores’ deformation without changing the applied pressure. Therefore, we believe that this system will bring new opportunities for many applications, such as gas-involved chemical reactions, fuel cells, multiphase separation, multiphase flow, multiphase microreactors, colloidal particle synthesis, and sizing nano/microparticles.This work was supported by the National Natural Science Foundation of China (grant no. 21673197), the Young Overseas High-level Talents Introduction Plan, the 111 Project (grant no. B16029). 研究工作得到国家自然科学基金委（项目批准号：21673197）和厦门大学校长基金（项目批准号：20720170050）等资助与支持

Protective effect of five-flavor sophora flavescens enteric-coated capsules on inflammatory bowel disease and its molecular mechanism

Abstract This study aims to investigate the effect of five-flavor sophora flavescens enteric-coated capsules (FSEC) on TNF-α-induced inflammatory bowel disease and its molecular mechanism. Wistar Rats were divided divided into 6 groups: Normal control group (group A): normal diet, drinking water; Model group (group B): 100 μg/L TNF-α; FSEC high-dose group (group C): 100μg/L TNF-α + FSEC (432 mg/kg); FSEC medium-dose group (group D): 100 μg/L TNF-α + FSEC (216 mg/kg); FSEC low-dose group (group E): 100 μg/L TNF-α + FSEC (108 mg/kg); Positive control group (group F): 100 μg/L TNF-α + 500 mg/kg sulfasalazine (SAZ). Animals in each group were intragastrically administered twice daily for 7 days. Animals were sacrificed 24 hours after the last treatment and colon tissues were collected for subsequent experiments. The results of HE staining showed that the colonic tissue of TNF-α-fed animals appeared damage, while the colonic tissue of animals treated with FSEC was improved to various degrees, and the histological characteristics of colon were basically recovered in the high-dose group, suggesting that FSEC could be used to treat TNF-α-induced colonic tissue damage. According to the results of ELISA and immunohistochemistry, the recovery of colonic tissue structure in rats treated with different doses of FSEC might be related to the decrease of TNF-α, IL-6, IL-17, TLR-4 and NF-κB proteins expression. According to the results of Western blotting, TNF-α-pretreated IEC-6 cells cultured with medicated serum decreased the expression of TRIF and IFN-γ proteins. These results suggest that FSEC has a protective effect on ulcerative colitis (UC), and the mechanism may be through inhibiting the activation of TLR-4/NF-κB signaling pathway and preventing the release of related inflammatory factors