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The lithology and hardness of the coal seam roof are directly related to the stability and water permeability of the roadway and the safe production of the coal mine. It has become a common method to predict gas content based on AVO inversion, but the conventional AVO inversion formula is a simplified approximation of Zoeppritz equation in different degrees under certain conditions, which affects the inversion accuracy to some extent. On the basis of petrophysical analysis of the roof, the pre-stack inversion of quasi-linear Zoeppritz equation with the smallest overall angle error was employed to lithology and hardness prediction of coal seam roof in Yangquan Mining Area, Shanxi Province. The results show that the expression of quasi-linear Zoeppritz equation is simple, and through the AVO characteristic analysis of different Zoeppritz approximate formulas, found that the precision of quasi-linear Zoeppritz equation is the highest, second only to that of accurate Zoeppritz equation. The analysis of rock mechanics characteristics shows that Young’s modulus multiplied by density is the most sensitive to hardness, and pseudo-gamma P-wave velocity can effectively reflect roof lithology. The lithology and hardness characterization parameters obtained from inversion are combined with the parameter well data and geological data to comprehensively evaluate the roof stability, provide geological evidence for roadway excavation and reduce the coal mine production risk.

With topological spin texture, magnetic domain walls have soliton-like dynamic behaviors in magnetic nanowires, which can be used in information transmission and storage technology. Therefore, precisely controlling the dynamic behavior of the magnetic domain wall and its pinning behavior is one of the important technical challenges in realizing domain-wall-based spintronic devices. In this work, a geometrically defect-free scheme for domain wall pinning/depinning is proposed using micromagnetic simulations based on a tie-shaped asymmetric nanowire, which can precisely control the position of the magnetic domain wall in an external magnetic field. The results show that the domain wall in tie-shaped nanowires exhibits excellent linear response and ultrafast time response to external magnetic fields, which endow them with potential applications for high-frequency weak-magnetic-field detection. We further propose a scheme for constructing a magnetic-field sensor using the tie-structured nanowire, and we study its feasibility. [ABSTRACT FROM AUTHOR]

As one of the most promising information carriers, the generation, manipulation, and detection of magnetic skyrmions have emerged as a hot topic in the field of spintronics. However, a major bottleneck to their practical application lies in the existing limitations of detection technology, which fails to accurately locate skyrmions or monitor their real-time motion behavior. In this work, we propose a patterned heterostructure scheme comprising a nanodot chain (NDC) layer and a skyrmion nano-racetrack layer for precise monitoring of skyrmion motion. By exploiting the stray field generated by the moving skyrmion within the racetrack layer, magnetization changes are induced in nanodots within the NDC layer. These changes then translate into high-frequency magnetization oscillation signals that encode valuable information about the dynamic characteristics of driven skyrmions, such as speed and acceleration of the skyrmion, either by spin waves or spin currents. This scheme holds great potential for advancing spintronic devices based on a profound understanding of skyrmion dynamics. [ABSTRACT FROM AUTHOR]

In LPS‐stimulated mouse inflammation model, Laoshan black tea polysaccharides (BTPSs) showed significant anti‐inflammatory activity. Three water‐soluble acidic polysaccharides (BTPS 3‐1, BTPS 3‐2, and BTPS 3‐3) were purified. They contained glucose (Glc), galactose (Gal), fucose (Fuc), rhamnose (Rha), glucuronic acid (GlcA), and mannose (Man) at molar ratios of 9.0 : 4.9 : 4.9 : 1.7 : 1.5 : 1.0, 9.5 : 5.3 : 4.9 : 1.7 : 1.6 : 1.0, and 5.3 : 3.5 : 2.0 : 2.1 : 0.9 : 1.0 with average molecular weights of 28.38, 14.39, and 11.00 kDa, respectively. Three polysaccharides reduced the levels of NO, TNF‐α, and IL‐6 in LPS‐induced RAW 264.7 cells, and BTPS 3‐2 had the strongest anti‐inflammatory effects. Based on analyses of the monosaccharide composition, methylation, and NMR, the main chain of BTPS 3‐2 was composed of ⟶4) ‐β‐D‐Glcp‐ (1⟶, ⟶2) ‐α‐L‐Fucp‐ (1⟶, and ⟶6) ‐β‐D‐Galp‐ (1⟶, and Rhap, GlcpA, and Manp units were attached as side chains to the backbone. BTPS 3‐2 also downregulated the expression levels of p‐NF‐κB p65, p‐IκBα, TLR4, MyD88, COX‐2, TNF‐α, and IL‐6. BTPS 3‐2 ameliorated LPS‐induced inflammation by regulating the TLR4/MyD88/NF‐κB signaling pathway. [ABSTRACT FROM AUTHOR]

This paper investigates a free boundary tumor model with time-dependent in the presence of inhibitors. The model consists of two diffusion equations representing nutrients and inhibitors respectively, and an ordinary differential equation describing the radius of the tumor $ R(t) $. We know that angiogenesis is not a steady-state process, in general, it changes over time, so it is reasonable to assume that tumors stimulate angiogenesis at a rate proportional to $ \alpha (t) $. We find the properties of the tumor radius $ R(t) $ is greatly tied to the properties of $ \alpha (t) $. When $ \alpha \left(t \right) $ is time-dependent, we prove that for any sufficiently small $ c_1 $: If $ \alpha (t) $ remains uniformly bounded, then $ R(t) $ also remains uniformly bounded; If $ \alpha (t) $ tends to zero as $ t \to \infty $, so does the tumor radius $ R(t) $; If $ \lim_{t \to \infty}\inf \alpha \left (t \right)>0, $ then $ \lim_{t \to \infty} \inf R\left (t \right)>0 $. Moreover, the global asymptotic stability of the steady-state solution is proved, and it is surprising to find that when $ \tilde u + \bar v $ is sufficiently small and $ \frac{\lambda }{{\mu \bar u}} < {c_1} \le{c_2} $, the solution will blow up. [ABSTRACT FROM AUTHOR]