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We study the magnetohydrodynamic flow around a circular cylinder confined in a rectangular duct. In this configuration, both the circular cylinder and the walls of the rectangular duct are electrically insulating, while the magnetic field aligns with the axial direction of the cylinder. The experimental measurements are performed by controlling two parameters Re and N (N is the ratio of electromagnetic forces to inertial forces) in the ranges of (180–722) and (0.8–264), respectively. Utilizing the electrical potential method, we employ both movable and wall probes to obtain the local flow velocities in the wake of the cylinder. By analyzing the space correlation of the signals obtained from the wall probes, a distinct transition in the flow behavior is observed, transitioning from a three-dimensional state to a quasi-two-dimensional (Q2D) state when the external magnetic field reaches a sufficient strength (N > 3). Additionally, the Q2D state allows for a further subdivision based on the scaling relationship R e / H a ∼ (0.41 – 0.42) in the stability map, thereby distinguishing between steady and unsteady flow states, which is consistent with findings from previous studies. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to analyze the physicochemical properties, primary structure and antioxidant activity of polysaccharide from Zizyphus jujuba cv. Banzao. Methods: The polysaccharides were prepared by water extraction and alcohol precipitation, deproteinization with trichloroacetic acid and decolorization with hydrogen peroxide. The physicochemical properties of polysaccharides were studied, and the possible structures were predicted by Ultraviolet-visible (UV-Vis) and infrared (IR) spectroscopy. Finally, the free radical scavenging ability was determined. Results: The polysaccharide from Z. jujuba cv. Banzao contained the content of total sugar and uronic acid with 52.30% and 46.22%, respectively, and showed 64.70% of esterification degree, which was an acidic pectin polysaccharide; UV-VIS and IR spectroscopy showed that the polysaccharide from Z. jujuba cv. Banzao had typical polysaccharide absorption peak, and contained no protein or nucleic acid. It was a pyranose with α-glycosidic bond, mainly composed of galacturonic acid, galactose, arabinose, glucose. The polysaccharides from Z. jujuba cv. Banzao displayed certain antioxidant activity and the free radical clearance of the polysaccharide at 1 mg/mL for DPPH radical, ·OH and ABTS+· were 23.64%, 21.01% and 13.84%, respectively. Conclusion: The polysaccharide from Z. jujuba cv. Banzao was an acidic pectin sugar mainly composed of galacturonic acid. Besides, it had α-glycosidic bond and showed strong antioxidant capacity, which can be used as a potential antioxidant.

The role of ASMase/ceramide signaling pathway in the development of silicosis needs to be verified by in vivo experiments. We investigated the role of the ASMase/ceramide signaling pathway in the progression of silicosis and the effect of desipramine (DMI) (1 mg/mL) on the development of silicosis, by establishing a silica (1 mL, 50 mg/mL) dust‐contaminated rat silicosis model and administering the ASMase inhibitor, DMI, to the dust‐contaminated rats. The results showed that the levels of interleukin (IL)‐1β and IL‐6 were increased in the lung tissues of the rats in the dust‐contaminated group at the initial stage after dusting; the inflammatory cell aggregation in the lung tissue was increased. With time progression, the hydroxyproline content in the lung tissue increased, and alpha‐smooth muscle actin (α‐SMA), collagen I, and vimentin substantially increased, suggesting that silicosis was formed in the lung tissue of the rats 28 days after SiO2 dust treatment. Moreover, the levels of ASMase, ceramide, and sphingosine‐1‐phosphate (S1P) were increased in the lung tissue of rats. The expression of β‐catenin, fibronectin, and caspase‐3 protein was increased, and E‐cadherin protein expression was decreased in the lung tissue of the rats in the late stage of dust contamination. The ASMase and ceramide in the lung tissues of the rats in the DMI intervention group were reduced, as were the lung tissue inflammation levels, collagen expression, and lung fibrosis. These results suggest that SiO2 dust may activate the ASMase/ceramide signaling pathway in rat lung tissue, promoting pulmonary fibrosis. DMI inhibited this activation, attenuated apoptosis, blocked epithelial–mesenchymal transition, and halted silica dust‐induced silicofibrosis. The aim of this study was to investigate the role of ASMase/ceramide signaling pathway in silica dust‐induced pulmonary fibrosis in rats. The results showed that inhibition of ASMase resulted in decreased indicators related to the ASMase/ceramide signaling pathway, reduced inflammatory responses and collagen in silicosis rats, and reduced degrees of apoptosis and EMT. Therefore, SiO2 dust may promote lung fibrosis formation by activating the ASMase/ceramide signaling pathway in rat lung tissue. [ABSTRACT FROM AUTHOR]

The southern Yidun Terrane formed in response to the westward subduction of the Garzê–Litang oceanic lithosphere. The Xiuwacu pluton, consisting of the Late Triassic biotite granite and Late Cretaceous monzogranite porphyry, is located in the northern portion of the southern Yidun Terrane. It hosts the Late Cretaceous quartz‐vein‐type Mo–W deposit genetically related to the intraplate monzogranite porphyry. However, the petrogenesis and magmatic fertility of the biotite granite remain unclear. Sixteen zircons from the biotite granite yield a weighted mean 206Pb/238U age of 217 ± 1.2 Ma, indicating that the biotite granite emplaced synchronously with the arc‐related andesites and porphyries in the southern Yidun Terrane. Unlike these slab melt‐derived adakitic rocks, the Xiuwacu biotite granites show typical I‐type granite affinities, with relatively high SiO2 contents, low Sr/Y ratios, and high Y contents. These granites display depleted zircon Hf isotopic signatures (ƐHf(t) = 0.6–3.8) but enriched whole‐rock Sr–Nd and zircon O isotopic signatures, suggesting that the mixing between juvenile materials and external enriched melts might have contributed to the generation of biotite granite. Moreover, they show relatively high Al2O3/(FeOT + MgO + TiO2), Th/Yb, and Th/Nb ratios, which are collectively indicative of the input of sediment melts extracted from subducting slab into the melt source of biotite granite. The high MgO, TiO2, F, and Cl contents of biotite and the excess Al of plagioclase suggest that the Xiuwacu biotite granites formed under high oxygen fugacities, magmatic water contents, and volatiles components and they might have Cu prospecting potentials. [ABSTRACT FROM AUTHOR]