Search

This study addresses the issue of carbody hunting in an electric locomotive induced by low wheel-rail contact conicity. The main objective is to mitigate this unstable motion by optimising the location of yaw dampers while ensuring bogie stability under high conicity conditions. A field test was first conducted to observe the carbody hunting behaviour, and a detailed locomotive dynamics model was then developed and validated using experimental data. The impact of yaw damper locations on locomotive stability was investigated, taking into consideration different carbody modes. The findings reveal the mechanism behind the deterioration of carbody stability due to the yaw damper installation angle and two installation layouts were proposed to enhance the carbody stability. Comparisons were then made with traditional solutions using both linear and nonlinear analysis, and experimental validation confirmed the effectiveness of the optimised yaw damper locations in improving carbody stability. This research highlights the importance of optimising the yaw damper's location to suppress carbody hunting, providing valuable insights for railway engineers and offering a promising solution for enhancing stability in high-speed train. [ABSTRACT FROM AUTHOR]

Purpose: To explore the influence of circulating lymphocyte subsets, serum markers, clinical factors, and their impact on overall survival (OS) in locally advanced nasopharyngeal carcinoma (LA-NPC). Additionally, to construct a nomogram predicting OS for LA-NPC patients using independent prognostic factors. Methods: A total of 530 patients with LA-NPC were included in this study. In the training cohort, Cox regression analysis was utilized to identify independent prognostic factors, which were then integrated into the nomogram. The concordance index (C-index) was calculated for both training and validation cohorts. Schoenfeld residual analysis, calibration curves, and decision curve analysis (DCA) were employed to evaluate the nomogram. Kaplan-Meier methods was performed based on risk stratification using the nomogram. Results: A total of 530 LA-NPC patients were included. Multivariate Cox regression analysis revealed that the circulating CD8+T cell, platelet-to-lymphocyte ratio (PLR), lactate dehydrogenase (LDH), albumin (ALB), gender, and clinical stage were independent prognostic factors for LA-NPC (p < 0.05). Schoenfeld residual analysis indicated overall satisfaction of the proportional hazards assumption for the Cox regression model. The C-index of the nomogram was 0.724 (95% CI: 0.669–0.779) for the training cohort and 0.718 (95% CI: 0.636-0.800) for the validation cohort. Calibration curves demonstrated good correlation between the model and actual survival outcomes. DCA confirmed the clinical utility enhancement of the nomogram over the TNM staging system. Significant differences were observed in OS among different risk stratifications. Conclusion: Circulating CD8+ T cell, PLR, LDH, ALB, gender and clinical stage are independent prognostic factors for LA-NPC. The nomogram and risk stratification constructed in this study effectively predict OS in LA-NPC. [ABSTRACT FROM AUTHOR]

Recently, research on complex networks has become a hot topic. Community detection, as a main task in social network analysis, plays an important role in complex networks. In this paper, we survey and summarize the development and trend of community detection and analyze typical algorithms presented in recent years. We first discuss the algorithms from algorithmic thinking, key technology and the advantages and disadvantages. Second, evaluation metrics and datasets are introduced. Finally, some application scenarios are pointed out for the potential application in the future. It is hoped that this review will serve as the steppingstone for those interested in community detection. [ABSTRACT FROM AUTHOR]

OBJECTIVE:Hepatitis B virus infection is a major social and economic burden in developing countries, especially in China. We aimed to evaluate the effects of hepatitis B surface antigen (HBsAg) positive status on the pregnancy outcomes in the Chinese population. METHODS:This retrospective cohort study was performed using data from the Medical Birth Registry of Xiamen, China, from January 2011 to March 2018. Multivariate logistic regression analysis was used to assess the association between the HBsAg status and pregnancy outcomes. RESULTS:This study included 3,789 HBsAg-positive women and 29, 648 non-exposed women. The HBsAg-positive pregnant women were slightly older in age (29.3±4.3 vs. 28.9±4.4, P< 0.001). Additionally, pregnant women with a positive HBsAg status had higher odds of gestational diabetes mellitus (GDM) (adjusted odds ratio [aOR], 1.13; 95% confidence interval [CI], 1.03-1.23), and cesarean delivery (aOR, 1.12; 95%CI, 1.03-1.21). The risk of infants being large or small-for-gestational age, having low-birth weight, and of macrosomia, preterm birth, and stillbirth did not differ significantly between the HBsAg-positive and-negative women. CONCLUSION:In Xiamen, China, the slightly higher risk of GDM and cesarean section in women positive for HBsAg should not be neglected. Further studies should be conducted to evaluate the effects of HBsAg positivity on the pregnancy outcomes in different ethnic populations.

In our work, a totally anomalous thermal quenching phenomenon of red-shifted and enhanced charge transfer state (CTS) absorption is found for the first time in LiTaO3:xPr3+ phosphors. The crystal structure, luminescent properties and the mechanism of abnormal thermal quenching were investigated in detail. [ABSTRACT FROM AUTHOR]

Praseodymium (Pr3+) ion and the transition metal vanadium (V5+) ion with d0 electronic configuration can form an intervalence charge transfer (IVCT) band, which can function both as a compensatory channel for its red emission and as a quenching channel, thus affecting the luminescence thermal stability of the phosphors. Research studies reveal that the emission of Pr3+ in the YVO4 matrix can be quenched by the IVCT mechanism, thereby limiting the application of phosphors. As such, the present contribution is based on the solid solution replacement strategy to inhibit the constitutent of the IVCT quenching channel and thus improve thermal stability. Therefore, phosphonium (P5+) with a valence state matching V5+ and a similar ion radius was selected for the V/P substitution. It lacks a d0 electron configuration, preventing the formation of an IVCT band with Pr3+ and thereby inhibiting the construction of the quenching channels to enhance thermal stability. While the empirical formula of IVCT indicates a decrease in the IVCT energy level from 3.32438 to 3.06251 eV upon the introduction of P5+, the PLE spectra demonstrate a sharp reduction in IVCT intensity, i.e., weakening of the quenching channel. The thermal stability of the phosphors at different excitation locations was enhanced with the rise of P5+ concentration. When excited at the 3P2 level, the Y0.995PO4:0.5%Pr3+ phosphor demonstrated highly stable red emission from 303 to 523 K, with a luminescence integrated intensity ranging from 95.5% to 105.3% compared to that at 303 K. This research provides a novel approach for inhibiting the IVCT quenching channel and broadens the commercial value of YVO4:Pr3+ phosphor for various applications. [ABSTRACT FROM AUTHOR]