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High-power insulated gate bipolar transistors (IGBTs) are important components of traction inverter. It is important to ensure the suitable temperature of the IGBT module for keeping the operation of trains efficient and safe. Due to the significant differences in train operating environment and traction performance, the cooling requirements for IGBT are also different. Therefore, identifying and matching various parameters of operating parameters of flow and heat transfer in high-power-density IGBT module liquid-cooling plate is of great significance to achieve optimal energy efficiency. Based on the Reynolds-averaged Navier–Stokes equations, shear stress transport k–ω turbulence model, and orthogonal experimental design, the flow and heat transfer characteristics of the liquid-cooling plate were simulated, and the numerical method and settings were verified experimentally. The results show that the single-parameter mapping relationship between the operating parameters and cooling performance indices (pressure drop, temperature rise, and maximum surface temperature, corresponding to Δp, ΔT, and Tmax, respectively) of the liquid-cooling plate is clear, and the flow rate and physical properties of the cooling liquid have significant effects on the cooling performance. The multi-objective optimization method based on the radial basis function surrogate model and nondominated sorting genetic algorithm II can match operating parameters under the minimum of Δp, Tmax and maximum of ΔT. Considering the appropriate values of the three indexes comprehensively based on Pareto optimal solution set, the error between the calculated value and the predicted value is less than 8 % when the inlet flow rate is 20 L/min, the temperature is 330.68 K, the pressure is 2.2 bar and the calorific value is 75.2 kW/m2. The results can be to provide a method and database for engineers to design liquid-cooling plate for high-speed train IGBT to achieve the highest efficiency.

Development of power packs suspended under the diesel train towards high power and high integration has been driven by the development of technology. The wind environment of the railway lines is complex and variable, strong crosswind would exacerbate the complexity of the airflow around the train, impacting the cooling-fan performance of power pack, smoke dispersion, posing safety concerns. Using incompressible RANS equations and SST k-ω model, flow field around a diesel train, and effect of train speed, crosswind, and skirt board on cooling-fan flow and smoke dispersion are simulated and analyzed. Results reveal that airflow in power pack fans is affected by train speed and location, with the upstream fan exhibiting slightly higher airflow, especially in tail car power packs, with a difference of up to 7% (at 160 km/h). Skirt boards reduce fan airflow by about 6%. Crosswinds positively correlate with fan airflow variation, with windward and leeward fans experiencing increased and decreased airflow, respectively. Skirt board effectively reduces crosswind effects on power pack fans. Smoke intake into air-conditioning units (ACUs) correlates positively with train speed, particularly in downstream air-intakes of ACUs near smoke vents. Crosswinds significantly alter smoke distribution between leeward and windward sides of ACUs, especially at low crosswind speed. Smoke rarely enters ACUs when crosswind speed exceeds train speed. These findings offer insights for combustion-powered train operation and smoke vent design on train roofs.

Lithium compounds, a classic class of metal complex medicine that target GSK 3β and are widely known as mood-stabilizer, have recently been reported as potential anti-tumor drugs. The objective of this investigation was to explore the anticancer potential of lithium chloride (LiCl) and elucidate its mode of action in pancreatic cancer cells. The MTT, colony formation, and Edu assay were used to evaluate the impact of LiCl on pancreatic cancer cell proliferation. Various methods were employed to investigate the anti-tumor activity of LiCl and its underlying mechanisms. Cell cycle analysis and apoptosis detection assays were utilized for in vitro experiments, while the orthotopic pancreatic cancer mouse model was employed to evaluate the effectiveness of LiCl treatment in vivo. Furthermore, the impact of LiCl on the proliferation of patient-derived organoids was also studied. The results demonstrated that LiCl inhibited the proliferation of pancreatic cancer (PC) cells, induced G2/M phase arrest, and activated apoptosis. Notably, the triggering of endoplasmic reticulum (ER) stress by LiCl was observed, leading to the activation of the PERK/CHOP/GADD34 pathway, which subsequently promoted apoptosis in PC cells. In the future, Lithium compounds could become an essential adjunct in the treatment of human pancreatic cancer.

Depression has several negative effects on emotion as well as learning and memory abilities. Previous studies showed that depression could exacerbate inflammation, which in turn further aggravated depression. Deferoxamine (DFO) is a chelating agent binding iron and aluminium, and is clinically applied to treat acute ion poisoning and hemochromatosis. Researches showed that it could reduce inflammation via increasing the expression of hypoxia-inducible factor-1alpha (HIF-1α). Here, we established a chronic unpredictable mild stress (CUMS) model to investigate whether DFO exerted a neuroprotective function in depression. The results demonstrated that CUMS (4 weeks) effectively induced depression-like behaviors in mice based on sucrose preference test (SPT), forced swim test (FST), tail suspension test (TST), open field test (OFT), and elevated plus-maze test (EPT). It also brought cognitive deficits based on Morris water maze (MWM) test and the impairment of synaptic plasticity based on in vivo electrophysiological recordings. Additionally, CUMS exposure significantly decreased the expression of hippocampal synapse related proteins and the spine density of neurons in the DG region, accompanied by increasing the expression of hippocampal inflammatory cytokines, and promoted the activation of microglia in the hippocampus. The expression of HIF-1α was down-regulated as expected. However, DFO distinctly reversed the CUMS-induced impairments. The mechanism is associated with the DFO inhibition of inflammation by upregulating HIF-1 expression, thereby alleviating a series of pathology changes. Together, these findings suggest that DFO likely plays a protective role in cognitive impairments and synaptic plasticity deficits resulting from depression.