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A bolter miner is a new type of mining machinery with cutting and anchoring functions. In order to study the best pick layout of bolter miner cutting head. Based on the constitutive relation of Holmquist-Johnson-Cook (HJC), three simulation models of different cutting heads were established, and the whole crushing process of coal-rock was simulated by finite element method (FEM). The influence of the cutting head on the cutting performance under the condition of different rotational speeds and pick layouts was intensively studied. The results show that the relationship of load fluctuation coefficient among the three pick layouts is as follows: sequential type > hybrid type I > checkerboard type. The circumferential pick layouts can reduce the load fluctuation coefficient of cutting head. The rotational speed from 20 to 40 r/min, the torque linearly decreases with the increase of rotational speed. The rotational speed increases from 40 to 50 r/min, the cutting torque is relatively stable. The specific energy of chessboard type is relatively higher than the other three cutting heads. The difference of specific energy between sequential type and hybrid type I is not more than 5.5%, and the reality of the simulation is verified by cutting experiments. The results were successfully applied to the first shield type bolter miner in China. [ABSTRACT FROM AUTHOR]

A labyrinth microstructure interconnected by micron and submicron acicular structures was successfully prepared by immersing nickel-aluminum bronze in 9 wt% FeCl3·6H2O solution at room temperature for 40 min. After being modified with 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane (FAS-17), the microstructure surface displays robustly low-adhesion superhydrophobicity, and the water contact angle is above 160 ° on it. In addition, the superhydrophobic surface exhibits excellent corrosion resistance and stability in 3.5wt % NaCl aqueous solution and corrosion solution with different pH values. [ABSTRACT FROM AUTHOR]

Aiming at the complex conditions of the first shielded bolter miner in the actual work, the mechanical model of bolter miner cutting head was established. Based on cutting mechanism of the conical pick and the cutting head, the cutting head load and torque analysis model under complex coal seam were established. The dynamic characteristics of load and torque in the process of cutting head are analyzed under three different working conditions of cutting roof-coal layers, coal-floor layers and coal seam by finite element method. The results show that when the damage variable D = 1, the coal-rock completely lacks the bearing capacity, and it forms arc-shaped crushing groove on the coal-rock. The large difference of torque between roof-coal layers and the roof-coal layers in the conical pick is 112 Nm, which indicates that the cutting head has the best performance with cutting the coal seam first and then cutting the rock. In the process of excavation, the load fluctuation coefficient of cutting the coal-floor layers and roof-coal layers is about 1.2 times of that of the coal seam. The results can provide a reference for the efficient cutting and performance evaluation of the bolter miner. [ABSTRACT FROM AUTHOR]

Background: Kimura's disease (KD) is a rare chronic inflammatory condition characterized by nodules and lymphadenopathy in the head and neck region, exhibiting type II inflammation. Dupilumab is commonly used against type II inflammation., Aim: To evaluate the efficacy and safety of dupilumab in KD patients., Design: The real-world study was conducted in a hospital in China., Methods: Six male patients with a mean age of 24.50 ± 15.47 years were treated with dupilumab following the same protocol as that for atopic dermatitis (AD). Clinical and laboratory indicators, such as maximum nodule diameter, blood eosinophil count, eosinophil percentage, and total serum IgE levels were assessed at baseline, Week 12 and Week 24. Adverse events were documented. Paired t-tests and one-way ANOVA were used for statistical analysis., Results: The results showed significant reductions in the longest nodule diameter at Week 12 (P = 0.006) and Week 24 (P = 0.017) compared to baseline. Blood eosinophil count decreased by 57.95% (P = 0.024) at Week 12 and 90.59% (P = 0.030) at Week 24. Eosinophil percentage decreased by 58.44% (P = 0.026) at Week 12 and 89.37% (P = 0.013) at Week 24. Total serum IgE levels decreased by 78.02% (P = 0.040) at Week 12 and 89.55% (P = 0.031) at Week 24. The presence of AD did not affect the results. One patient experienced temporary facial erythema after 32 weeks of treatment, which resolved with topical treatment. No other adverse events were reported., Conclusion: Dupilumab demonstrated effectiveness in treating KD without severe adverse events., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective: To analyze the role of oxycodone in acute lung injury(ALI) induced by lipopolysaccharide (LPS) in rats., Methods: Male SD rats were randomly allocated into 4 groups: control group, oxycodone group, LPS group, LPS+ oxycodone group. The effects of oxycodone on LPS-induced neutrophils influx, inflammatory cytokines release, pulmonary edema, apoptotic cell were examined. In addition, the toll-like receptor 4 (TLR4) in lung tissues was detected by Western blotting., Results: Oxycodone significantly attenuated LPS-induced pulmonary histopathologic changes, alveolar hemorrhage, and neutrophil infiltration. The lung wet-to-dry weight ratio, was markedly decreased by oxycodone(5.60±0.24 vs 6.80±0.27, P<0.05 ). Moreover, oxycodone decreased the productions of the inflammatory cytokines including IL-1β, TNF-α, HMGB-1((1 208±18)pg/ml, (1 660±14) pg/ml, (61±4) pg/ml , all P<0.05). Oxycodone treatment also reduced the concentration of apoptosis in lung tissues(18.6%±0.5%, P<0.05). Furthermore, the expression of TLR4 was significantly suppressed by oxycodone treatment in lung tissues(1.20±0.15, P<0.05)., Conclusions: Oxycodone exerts protective effects on LPS-induced ALI in rats. The potential mechanism of this action may attribute partly to the inhibition of TLR4 activation.