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An experimental study is conducted to investigate the surface integrity in spindle barrel finishing of 14CrMnSiNi2MoA aviation cylindrical spur gears. The surface morphology, residual stress, microhardness, microstructure of aviation gears before and after barrel finishing are systematically studied by professional instruments. The results indicate that the gear surface integrity can be significantly improved by spindle barrel finishing. The surface roughness of the gear reduces to less than 0.2 μm and the average residual compressive stress of the gear surface increases by about 45%. The hardness of the gear surface also increases. The results of surface roughness and residual stress distribution before and after barrel finishing reveal that the increase of residual compressive stress and decrease of roughness of the gear surface increase gradually from the root to the top of the gear, which provides a basis for the setting and designing of processing parameters in barrel finishing.

In this paper, we mainly concern with the system of the coupled nonlinear Schrödinger equation with initial data in critical spaces in dimension 3. We first obtain the global well-posedness of the solution to the coupled nonlinear Schrödinger equation with initial data in a critical space $ W^{\frac {11}{7}, \frac 76}({\mathbb {R}}^3) $ W 11 7 , 7 6 ( R 3). The key is to derive a uniform bound of a modified energy $ \mathcal {E}(t) $ E (t) based on a decomposition for the solution as in Dodson [Global well-posedness for the defocusing, cubic nonlinear Schrödinger equation with initial data in a critical space. Rev Mat Iberoam. 2022;38:1087–1100]. In addition, inspired by Dodson [Scattering for the defocusing, cubic nonlinear Schrödinger equation with initial data in a critical space. International mathematics research notices; 2023], we make a new decomposition for the solution and show the scattering to the coupled nonlinear Schrödinger equation with radially symmetric initial data in a critical Besov space $ B_{1,1}^2({\mathbb {R}}^3) $ B 1 , 1 2 ( R 3). [ABSTRACT FROM AUTHOR]

Introduction: Subglottic stenosis, manifested by granulation tissue hyperplasia, is challenging and requires multiple repeated treatments and stent maintenance at times. Corticosteroids prevent severe subglottic stenosis development owing to their antifibrotic and anti-inflammatory properties. Submucosal injection of glucocorticoids, a useful adjuvant therapeutic method, improves the mean interval between endoscopic procedures and reduces airway restenosis risks. Case Presentation: We report a rare case of a man with complex subglottic stenosis who underwent balloon dilatation combined with cryotherapy, stent placement, and adjuvant submucosal triamcinolone injection. The drug was injected efficiently and safely into the submucosal layer under percutaneous ultrasound guidance, and subglottic stenosis was well-controlled at a low cost. Conclusion: POCUS-guided medication injections may be a useful adjuvant medical therapy for subglottic stenosis. [ABSTRACT FROM AUTHOR]

Background: Cancer burden from the elderly has been rising largely due to the aging population. However, research on the long‐term epidemiological trends in cancer of the elderly is lacking. Methods: Registry data of this population‐based cross‐sectional study were from the Surveillance, Epidemiology, and End Results (SEER) database. The study population aged 65 years or more, from geographically distinct regions. Joinpoint regression and JP Surv method were used to analyze cancer trends and survival. Results: Mortality rate during 1975–2020 decreased from 995.20 to 824.99 per 100,000 elderly persons, with an average annual decrease of 0.421% (95% CI, 0.378–0.464). While overall incidence increased with no significance. Prostate (29%) and breast (26%) cancer were the most common malignancies, respectively, in elderly males and females, and the mortality for both of the two (prostate 15%, breast 14%) ranked just behind lung and bronchus cancer, which had the highest mortality rates in males (29%) and females (23%). Many cancers showed adverse trends in the latest follow‐up periods (the last period calculated by the Joinpoint method). For intrahepatic cholangiocarcinoma, incidence (male Annual Percentage Change [APC] = 7.4*; female APC = 6.7*) and mortality (male APC = 3.0*; female APC = 3.3*) increased relatively fast, and its survival was also terrible (3‐year survival only 10%). Other cancers with recent increasing mortality included cancer of anus, anal canal and anorectum, retroperitoneum, pleura, peritoneum, etc. Most cancers had favorable trends of survival during the nearest follow‐up period. Conclusion: Against the background of overall improvement, many cancers showed adverse trends. Further research for the underlying mechanisms and targeted implements towards adverse trends is also urgent. [ABSTRACT FROM AUTHOR]