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Abstract Under the background of urbanization and the rapid development of urban rail transit (URT), serious attention has been focused on URT network reliability in recent years. In this work, in order to measure network reliability, three indicators are constructed based on passengers’ tolerable travel paths, passenger travel efficiency and passenger travel realization on a URT network. The passenger tolerability coefficient, which is the ratio of passengers’ tolerable travel time to the shortest possible travel time, is proposed and added to the indicators. It reflects passengers’ behavior with respect to choice of travel paths. The ratio of affected passenger volume (RAPV) is proposed to identify important stations. Finally, the connectivity reliability of Wuhan’s subway network is analyzed by simulating attacks on stations. The results show that the degree centrality, betweenness centrality and RAPV indicators of stations can effectively identify the important stations that have a significant impact on the connectivity reliability of the network. In particular, the RAPV indicator effectively identifies stations that have the greatest influence on passenger travel realization. The connectivity reliability of Wuhan’s subway network is sensitive to passenger tolerability coefficient, and reliability is greater during non-peak hours than during peak hours. In addition, the stations that are important to the connectivity reliability of the Wuhan subway have two features, i.e., they are located at the center of the city, and they are important for connecting subgraphs of the network.

In daily operation, urban rail transit (URT) systems often experience disturbances that result in a partial reduction in transport capacity [partial disturbances (PDs)] rather than disturbances leading to a complete reduction in transport capacity. However, research that assesses the resilience of URT networks under PDs remains limited. This paper addresses this gap by proposing a passenger-oriented resilience assessment model for URT networks under PDs, considering the travel behaviors of passengers and different relations (i.e., linear, concave, and convex) between the velocity coefficient and failure severity. A simulation-based assessment approach was developed to solve the resilience assessment model. A numerical experiment was conducted on the Chengdu subway network in China. The results demonstrate that the performance indicator employed herein reflects the impact of passenger travel time distribution on network performance. Deliberate PDs cause more significant performance losses than random PDs. Moreover, the network is the least resilient under PDs considering the convex relation between the velocity coefficient and failure severity. The resilience-based critical link of each line is not fixed and varies with the failure severity and disturbance occurrence time. Increasing the failure severity of PDs results in more severe performance losses than increasing the number of PDs. Additionally, the passenger-oriented resilience of a URT network can be enhanced by improving the passengers’ tolerable delay time and disturbance duration. [ABSTRACT FROM AUTHOR]

Bladder cancer that occurs on the bladder mucosa is the most common malignant tumor in the urinary system. Exposure to aromatic amine chemicals and cigarette smoking are the two risk factors which causes bladder cancer. The mechanism of complex molecular signaling during its progress is still not understood clearly. High expression of metastasis associated gene 2 (MTA2) in malignant tumors such as ovarian cancer and hepatocellular carcinoma indicates its possible relationship with migration and invasion. However, expression level and biological function of MTA2 in bladder cancer tissues have not been studied. Here, we investigated the biological function, regulation mechanism and clinical application of metastasis-related genes 2 (MTA2). The expression level of MTA2 in various bladder tumor cells was determined by Western Blot. T24 and EJ cells were selected for in vitro study. T24 cells and EJ cells were transfected with viral vector and SiMTA2, respectively, to induce MTA2 over- or low- expression. MTS colorimetric assay was used to explore the proliferative ability of bladder cancer cells in vitro under MTA2 over- or low-expression. Matrigel invasion assay and Transwell migration assay were used to detect the invasion and migration of cancer cells in vitro under different MTA2 expression conditions. The results of Western Blot assay on bladder cancer cell lines have shown that the MTA2expression level to be significantly lower in T24 cells compared to that of EJ and J82 cells. MTA2 level was significantly higher in MTA2 overexpressed T24 cells than those in the non-transfected and CD511B transfected bladder cancer cells, while the level of MTA2 was much lower in the MTA2-knockdown EJ cells than that in the non-transfected and si-NC transfected. The MTS colorimetric assay significant increase in proliferation of T24 cells with MTA2 overexpression, while the proliferation of EJ cells with MTA2 knockdown was decreased. Results of Transwell migration assay showed that MTA2 overexpression could significantly increase the migration ability of T24 cells, and MTA2 knockdown could significantly reduce the migration ability of EJ cells. Matrigel invasion assay showed that MTA2 overexpression could enhance the invasive ability of T24 cells significantly, while MTA2 knockdown weaken the invasive ability of EJ cells. The expression level of E-cadherin was lower in the T24 cells with MTA2 overexpression than that in the non-transfected group and CD511B transfected group, but the expression level of N-cadherin protein was significantly higher in the T24 cells with MTA2 overexpression compared to the other two groups. The expression level of E-cadherin protein was significantly higher in the EJ cells with MTA2 knockdown than that of the non-transfected group and si-NC transfected group, while the expression level of N-cadherin protein was significantly lower than that in the non-transfected group and si-NC transfected group. [ABSTRACT FROM AUTHOR]