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Mounting evidence indicates the potential involvement of ATP-citrate lyase (ACLY) in the modulation of various cancer types. Nevertheless, the precise biological significance of ACLY in gastric cancer (GC) remains elusive. This study sought to elucidate the biological function of ACLY and uncover its influence on peritoneal metastasis in GC. The expression of ACLY was assessed using both real-time quantitative PCR and western blot techniques. To investigate the impact of ACLY on the proliferation of gastric cancer (GC) cells, colony formation and 5-ethynyl-2'-deoxyuridine (EdU) assays were performed. The migratory and invasive abilities of GC were evaluated using wound healing and transwell assays. Additionally, a bioinformatics analysis was employed to predict the correlation between ACLY and HIF-1A. This interaction was subsequently confirmed through a chromatin immunoprecipitation (ChIP) assay. ACLY exhibited upregulation in gastric cancer (GC) as well as in peritoneal metastasis. Its overexpression was found to facilitate the proliferation and metastasis of GC cells in both in vitro and in vivo experiments. Moreover, ACLY was observed to play a role in promoting angiogenesis and epithelial-mesenchymal transition (EMT). Notably, under hypoxic conditions, HIF-1A levels were elevated, thereby acting as a transcription factor to upregulate ACLY expression. Under the regulatory influence of HIF-1A, ACLY exerts a significant impact on the progression of gastric cancer, thereby facilitating peritoneal metastasis. [ABSTRACT FROM AUTHOR]

In this study, the effect of the freight train formation on the train aerodynamic performance was studied. Six cases involving a locomotive (LM) and three different freight vehicles – a boxcar (BC), a tanker (TK), and a double-container freight wagon (DW), were compared and analyzed. The results showed that the aerodynamic drag was significantly affected by the freight train formation type, and the total drag force in Case 2 (LM + BC + DW + TK) was the smallest. Furthermore, the flow field around the train was analyzed to reveal the influence mechanism of the different types of freight train formations on the aerodynamic drag. The car position and the adjacent cars had significant effects on the aerodynamic characteristics of the train. The DW had a greater effect on the pressure and velocity distributions around the train. In addition, the variations of the vortices in the near wake of the same tail car were inconsistent, although there were similar characteristics for the same tail car. [ABSTRACT FROM AUTHOR]

Field tests were carried out to measure the wheel-rail forces of a high-speed train passing by a windbreak breach with a crosswind speed and a train speed of 32 m/s and 120 km/h, respectively. Unsteady Reynolds-averaged Navier-Stokes simulations and multibody dynamic simulations were carried out to reproduce the field test experiments. The results obtained indicated that the side force and yawing moment of the train plays a key role in the safety of the head and the tail of the train when it passes by a windbreak breach. By analysing the flow structures, the reasons behind the different aerodynamic loads on the train head and tail were discussed. Based on the vehicle movement, the maximum derailment coefficient (0.8) of the train head appeared to be at a higher risk of danger as compared to the maximum derailment coefficient (0.2) of the train tail. This is due to the wind loads on the train head which compel the bogies to relatively move with the carbody along the lateral direction one more time than the train tail. Whereas, for the train tail, there is no relative motion between the carbody and bogies on the tail. [ABSTRACT FROM AUTHOR]

It is of great significance to analyze the influence mechanism of MIG welding parameters during thermo-mechanical coupling to improve the MIG welding process. In this paper, the Python script and the birth and death element method are used to realize the transient growth of a weld, the moving load of the welding heat source was realized by a Fortran subroutine, and a thermo-mechanical coupling model for the SUS301L-HT stainless steel MIG welding process is established. The temperature field and the thermal stress field are calculated. On this basis, a response surface model is established by the BOX-Behnen Design (BBD) method, and the sensitivity of welding process parameters to the influence of welding process is calculated by combining the Monte Carlo method with the response surface model. The calculation shows that the welding current and the welding speed have the most significant effect during the MIG welding of SUS301L-HT stainless steel, while the arc voltage has a relatively weak effect on the welding. The V-shaped angle has a great influence on the deformation angle of the welded workpiece. [ABSTRACT FROM AUTHOR]

To reduce the impact of a mountain ridge on the crosswind flow field of a specific section of the Lanzhou-Xinjiang high-speed railway, a portion of the mountain ridge was removed to increase the distance from the windbreak. To verify the effects of this flow optimization measure, the wind speed and wind angle were tested in this mountain ridge region. In this paper, under the actual conditions of this specific case study, the average and transient wind characteristics were analyzed based on the test results. Then, based on the actual terrain model, using the computational fluid dynamics (CFD) method with two inlet boundary conditions, namely, constant wind and exponential wind, the results obtained from the two boundary conditions were validated. Furthermore, the visualized flow structures and wind speed distributions along the railway under both boundary conditions were compared. Finally, along the railway, the impacts of different terrain types on the flow field of the railway were compared. [ABSTRACT FROM AUTHOR]

Double unit trains running at high speeds may create additional aerodynamic challenges due to two streamlined structures with close proximity, exploring the aerodynamic performance of double unit trains is now critical. In this study, detached eddy simulation (DES) approach was employed to study the aerodynamic performance and the nearby flow patterns of a double unit train, whose results were compared and analyzed with that of a single-unit train with a same length. The results showed that the coupling method could change the aerodynamic drag on each car and tended to increase the overall drag of the double unit train. The lift force of the front car near the coupler was significantly increased. Similar slipstream distributions were found around the front half single and double-unit train except in a region close to the coupler. Due to the coupling structure, the slipstream of the rear half of double unit train was much stronger compared to single unit train. The vortex region behind the double-unit train was much wider than that of the single-unit train and was accompanied by greater vortex-shedding. [ABSTRACT FROM AUTHOR]

A certain gap spacing between adjacent vehicles is usually inevitable in wind tunnel force tests of high-speed trains under no crosswind, which may affect the wind tunnel test results. Thus, to understand the influence of gap spacings on the train aerodynamics, the aerodynamic drag, pressure distributions and airflow structures of 1/8th-scale high-speed train models with gap spacings of 0, 5, 8, 10, 20, and 30 mm were studied using RANS based on SST k-ω turbulence model. The simulation method was verified by the wind tunnel experiment data. The results show that the gap spacing significantly affects the airflow structure around inter-car gap and aerodynamic resistances of train models. For the high-speed train model scaled at 1/8th at zero yaw, compared with gap spacing of 0 mm, the gap spacings lead to a significant reduction in the aerodynamic drag of the head car and an increase in that of the tail car, whereas which of the middle car is not significant. The maximum difference of the drag coefficient of the entire train model is smaller than 2.0%. When the gap spacing does not exceed 8 mm, the discrepancies of the drag coefficients of three cars are within 6.15%. [ABSTRACT FROM AUTHOR]

In areas with strong wind, windbreaks are built along railways to reduce the impact of wind on trains. However, because of the restrictions imposed by actual terrain, windbreak structures are often not uniform, such as from a cutting to an embankment, resulting in a discontinuous transition region. When a train runs through this region, a distinct yawing phenomenon occurs. This study numerically explored the aerodynamic features of a train running through a rectangular windbreak transition region. The variations in the pressure, side force, and moment of a train were analyzed, and the flow field features were clarified. Furthermore, the yawing motion of the car body with time was described. Finally, based on EN14067-6, the critical wind speed was obtained using the safety assessment of a train running through a windbreak transition region. [ABSTRACT FROM AUTHOR]