Unifying ultrafast demagnetization and intrinsic Gilbert damping in Co/Ni bilayers with electronic relaxation near the Fermi surface

The ability to controllably manipulate the laser-induced ultrafast magnetic dynamics is a prerequisite for future high speed spintronic devices. The optimization of devices requires the controllability of the ultrafast demagnetization time, , and intrinsic Gilbert damping, . In previous attempts to establish the relationship between and , the rare-earth doping of a permalloy film with two different demagnetization mechanism is not a suitable candidate. Here, we choose Co/Ni bilayers to investigate the relations between and by means of time-resolved magneto-optical Kerr effect (TRMOKE) via adjusting the thickness of the Ni layers, and obtain an approximately proportional relation between these two parameters. The remarkable agreement between TRMOKE experiment and the prediction of breathing Fermi-surface model confirms that a large Elliott-Yafet spin-mixing parameter is relevant to the strong spin-orbital coupling at the Co/Ni interface. More importantly, a proportional relation between and in such metallic films or heterostructures with electronic relaxation near Fermi surface suggests the local spin-flip scattering domains the mechanism of ultrafast demagnetization, otherwise the spin-current mechanism domains. It is an effective method to distinguish the dominant contributions to ultrafast magnetic quenching in metallic heterostructures by investigating both the ultrafast demagnetization time and Gilbert damping simultaneously. Our work can open a novel avenue to manipulate the magnitude and efficiency of Terahertz emission in metallic heterostructures such as the perpendicular magnetic anisotropic Ta/Pt/Co/Ni/Pt/Ta multilayers, and then it has an immediate implication of the design of high frequency spintronic devices

Role of glabridin in maintaining residual kidney function in dialysis patients

Purpose: To demonstrate the effect of glabridin on peritoneal function and residual renal function (RRF) in peritoneal dialysis (PD) patients.Methods: Twenty five patients (age range, 24 - 58 years) with a glomerular filtration rate of above 2 mL/min/1.73 m2 and on PD were subjected to glabridin therapy. The patients were treated daily with glabridin (30 mg) for 6 months. The baseline parameters for serum high-sensitivity C-reactive protein (hs-CRP), vascular endothelial growth factor (VEGF), and transforming growth factor β (TGF-β) were compared with those found after 6 months of glabridin treatment. In addition, end-to-initial dialysate concentration of glucose (D4/D0 glucose), dialyzer clearance of urea (K), dialysis time (t), volume of distribution of urea (V), peritoneal transport status as well as dialysate cancer antigen 125 (CA125) were also compared.Results: The results revealed a significant increase in mean dialysate CA125 after glabridin treatment (25.6 ± 2.7 U/mL) compared with baseline value (19.7 ± 3.2 U/mL). However, serum hs-CRP, VEGF, TGF-β, CTGF, daily ultrafiltration, D4/D0 glucose, Kt/V, and peritoneal transport status remained unaffected. Residual glomerular filtration rate in all the patients decreased. Glabridin treatment also led to a decrease in the decline of peritoneal function, suppression of elevation of profibrotic markers, and increased mesothelial cell mass in PD patients.Conclusion: Thus, glabridin is a potent candidate for the treatment of residual kidney function in dialysis patients.Keywords: Glabridin, Residual renal function, Peritoneal function, Dialysate, Profibrotic markers, Mesothelial cell mass, Glomerular filtration rat

Towards Understanding Theoretical Advantages of Complex-Reaction Networks

Complex-valued neural networks have attracted increasing attention in recent years, while it remains open on the advantages of complex-valued neural networks in comparison with real-valued networks. This work takes one step on this direction by introducing the \emph{complex-reaction network} with fully-connected feed-forward architecture. We prove the universal approximation property for complex-reaction networks, and show that a class of radial functions can be approximated by a complex-reaction network using the polynomial number of parameters, whereas real-valued networks need at least exponential parameters to reach the same approximation level. For empirical risk minimization, our theoretical result shows that the critical point set of complex-reaction networks is a proper subset of that of real-valued networks, which may show some insights on finding the optimal solutions more easily for complex-reaction networks

Study on Safety Control of Composite Roof in Deep Roadway based on Energy Balance Theory

Improving the safety and stability of composite roof in deep roadway is the strong guarantee for safe mining and sustainable development of coal mines. With three roadways of different composite roofs in Hulusu Coal Mine and Menkeqing Coal Mine as the research background, this paper explores the mechanical properties and energy dissipation law of coal-rock structures with different height ratios from the perspective of energy release and dissipation through lab experiments. The results indicate that the key to the stability of coal-rock structures lies in maintaining relatively low dissipation energy. Based on experimental results and the energy balance theory, two support principles were put forward and applied to experimental roadways. The field monitoring results show that the anchoring force on different composite roof displays different characteristics, proving that the work done by the support can adjust timely to the energy release and conversion so as to improve the safety and stability of roadways with different composite roofs. This study provides a reference for the deformation control in deep roadways with composite roofs under similar conditions