Search

The generation and evaluation of severely high thermal stress (σ) is known to be responsible for failure of thermal barrier coatings (TBCs) during thermal cycling. It is crucial and challenging to capture fluctuations in σ caused by the phase transition, which has motivated us to develop a high-throughput multiscale evaluation method for σ in TBCs that considers the phase transition of the top ceramic materials by coupling first-principles calculations with finite element simulations. The method quantitatively evaluates and visualizes σ of the real TBC structure under thermal cycling by multifield coupling. Additionally, the thermophysical properties calculated by the first-principles calculations consider the effects of temperature and phase transition, which not only reduces the cost of obtaining data but also has a more physical connotation. In this work, rare earth tantalites (RETaO4) are introduced as ceramic layers, and the results demonstrate that σ undergoes a rapid escalation near the phase transition temperature (Tt), particularly in the TBCs_GdTaO4 system, where it rises from 224 to 435 MPa. This discontinuity in σ may originate from the significant alterations in Young’s modulus (increase by 27%–78%) and thermal conductivity (increase by 53%–146%) near Tt. The TBCs_NdTaO4 and TBCs_SmTaO4 systems exhibit noteworthy temperature drop gradients and minimal σ fluctuations, which are beneficial for extending service lifetime of TBCs. This approach facilitates the prediction of failure mechanisms and provides theoretical guidance for the reverse design of TBC materials to obtain low thermal stress systems.

The improvement of cetane number of gasoline diesel blend fuel (GDBF) with the addition of 2-ethylhexyl nitrate (EHN) is rarely mentioned or quantified in the reported studies. In this work, combustion and emission characteristics of GDBF with 50 % gasoline (G50) with 1‰–3‰ EHN addition were compared on a single cylinder compression ignition engine. Then New European Driving Cycle driving cycle test was conducted on a commercial SUV equipped with the same 4-cylinder engines running with diesel and G50 with 3 ‰ EHN. The results show that with EHN addition, ignition delay of G50 were shortened and the coefficient of variation were reduced, indicating the improved combustion stability. Adding 3 ‰ EHN, the total hydrocarbon (THC) and carbon monoxide (CO) emissions of G50 were reduced by up to 85 %, and 50 %, respectively, while nitric oxide (NOx) was increased slightly. The cetane number of G50 added by 1 ‰, 2 ‰, and 3 ‰ EHN were 40.83, 44.25 and 45.8, respectively. The driving cycle test shows that the vehicle can run smoothly and well catch the speed demand of the driving cycle. Compared with diesel, G50E3 exhibits lower the exhaust absorption coefficient and fuel consumption with higher but comparable emission factors of CO, THC and NOx.

Abstract In order to reduce the thermal stress in high chromium cast iron (HCCI) matrix composites reinforced by zirconia toughened alumina (ZTA) ceramic particles, finite element simulation is performed to optimize the geometric configuration of ceramics perform. The previous model simplifies the overall structure of the ceramic particle preform and adds boundary conditions to simulate the particles, which will cause uncontrollable error in the results. In this work, the equivalent grain models are used to describe the actual preform, making the simulation results closer to the actual experimental results. The solidification process of composite material is simulated, and the infiltration between molten iron and ceramic particles is realized. Thermal stress in solidification process and compression stress distribution are obtained. The results show that adding 10-mm round holes on the preform can improve the performance of the composite, which is helpful to prevent the cracks and increases the plasticity of the material.

Abstract Background Docetaxel resistance represents a significant obstacle in the treatment of prostate cancer. The intricate interplay between cytokine signalling pathways and transcriptional control mechanisms in cancer cells contributes to chemotherapeutic resistance, yet the underlying molecular determinants remain only partially understood. This study elucidated a novel resistance mechanism mediated by the autocrine interaction of interleukin-11 (IL-11) and its receptor interleukin-11 receptor subunit alpha(IL-11RA), culminating in activation of the JAK1/STAT4 signalling axis and subsequent transcriptional upregulation of the oncogene c-MYC. Methods Single-cell secretion profiling of prostate cancer organoid was analyzed to determine cytokine production profiles associated with docetaxel resistance.Analysis of the expression pattern of downstream receptor IL-11RA and enrichment of signal pathway to clarify the potential autocrine mechanism of IL-11.Next, chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) was performed to detect the nuclear localization and DNA-binding patterns of phosphorylated STAT4 (pSTAT4). Coimmunoprecipitation and reporter assays were utilized to assess interaction between pSTAT4 and the cotranscription factor CREB-binding protein (CBP) as well as their role in c-MYC transcriptional activity. Results Autocrine secretion of IL-11 was markedly increased in docetaxel-resistant prostate cancer cells. IL-11 stimulation resulted in robust activation of JAK1/STAT4 signalling. Upon activation, pSTAT4 translocated to the nucleus and associated with CBP at the c-MYC promoter region, amplifying its transcriptional activity. Inhibition of the IL-11/IL-11RA interaction or disruption of the JAK1/STAT4 pathway significantly reduced pSTAT4 nuclear entry and its binding to CBP, leading to downregulation of c-MYC expression and restoration of docetaxel sensitivity. Conclusion Our findings identify an autocrine loop of IL-11/IL-11RA that confers docetaxel resistance through the JAK1/STAT4 pathway. The pSTAT4-CBP interaction serves as a critical enhancer of c-MYC transcriptional activity in prostate cancer cells. Targeting this signalling axis presents a potential therapeutic strategy to overcome docetaxel resistance in advanced prostate cancer. Graphical Abstract

Abstract Background Prostate cancer is a leading cause of cancer-related deaths among men worldwide. Docetaxel chemotherapy has proven effective in improving overall survival in patients with castration-resistant prostate cancer (CRPC), but drug resistance remains a considerable clinical challenge. Methods We explored the role of Ribonucleotide reductase subunit M2 (RRM2), a gene associated with senescence, in the sensitivity of prostate cancer to docetaxel. We evaluated the RRM2 expression, docetaxel resistance, and ANXA1 expression in prostate cancer cell lines and tumour xenografts models. In addition, We assessed the impact of RRM2 knockdown, ANXA1 over-expression, and PI3K/AKT pathway inhibition on the sensitivity of prostate cancer cells to docetaxel. Furthermore, we assessed the sensitivity of prostate cancer cells to the combination treatment of COH29 and docetaxel. Results Our results demonstrated a positive association between RRM2 expression and docetaxel resistance in prostate cancer cell lines and tumor xenograft models. Knockdown of RRM2 increased the sensitivity of prostate cancer cells to docetaxel, suggesting its role in mediating resistance. Furthermore, we observed that RRM2 stabilizes the expression of ANXA1, which in turn activates the PI3K/AKT pathway and contributes to docetaxel resistance. Importantly, we found that the combination treatment of COH29 and docetaxel resulted in a synergistic effect, further augmenting the sensitivity of prostate cancer cells to docetaxel. Conclusion Our findings suggest that RRM2 regulates docetaxel resistance in prostate cancer by stabilizing ANXA1-mediated activation of the PI3K/AKT pathway. Targeting RRM2 or ANXA1 may offer a promising therapeutic strategy to overcome docetaxel resistance in prostate cancer. Graphical Abstract

To alleviate farmer poverty, this paper investigates the effect of a retailer’s different socially responsible practices on a two-echelon supply chain consisting of one rural (poor) farmer, one suburban farmer, and one common retailer. Different from a commercial supply chain (whose members’ objectives are to maximize their profits) and a humanitarian supply chain (whose objective is to save more people, rather than to prioritize profits), the paper aims to study a development supply chain where the CSR-conscious retailer aims to lift the poor farmer out of poverty through cost sharing, altruistic practices, or fairness practices. Can the CSR-conscious retailer (and the development supply chain) do well by doing good? To answer the above question, four models of potential CSR investment are established and analyzed. Considering the different influences of the retailer’s CSR practices, this paper uses a Stackelberg game to analyze the decisions and profits of the farmers and the retailer in these four models. Our study finds that, first, the retailer’s CSR practices can improve the whole supply chain’s performance, which means that the supply chain has the potential to achieve the Pareto improvement for both the farmers and the retailer. Second, the retailer’s CSR practices yield benefits while implementing cost-sharing or fairness practices. Third, the rural farmer always benefits from the retailer’s CSR practices and may prefer the altruistic practice from which they can benefit the most. In addition, to benefit their profit more, the rural farmer should grow high- or low-value-added crops rather than medium-value-added ones. Fourth, from the suburban farmer’s perspective, the retailer’s CSR practices are not beneficial for their performance. However, the extent to which the suburban farmer’s performance decreases is much lower than the extent to which the rural farmer’s performance improves. The results of this paper might be used by stakeholders to alleviate poverty.