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Thermal barrier coatings (TBCs) are critical for protecting hot-section components in gas turbines and aero-engines. Traditional yttria-stabilized zirconia (YSZ) coatings are prone to phase transformation and sintering-induced failure at elevated temperatures. This study fabricated CeScYSZ (4 mol% CeO2 and 6 mol% Sc2O3 co-doped YSZ)/NiCrAlY TBCs using atmospheric plasma spraying (APS). A five-factor, four-level orthogonal experimental design was employed to optimize spraying parameters, investigating the influence of powder feed rate, spray distance, current, hydrogen flow rate and primary gas flow rate on the coating’s microstructure and mechanical properties. The resistance to calcium–magnesium–alumino–silicate (CMAS) corrosion was compared between CeScYSZ and YSZ coatings. The results indicate that the optimal parameters are a spray distance of 100 mm, current of 500 A, argon flow rate of 30 L/min, hydrogen flow rate of 6 L/min, and powder feed rate of 45 g/min. Coatings produced under these conditions exhibited moderate porosity and excellent bonding strength. After exposure to CMAS corrosion at 1300 °C for 2 h, the CeScYSZ coating demonstrated significantly superior corrosion resistance compared to YSZ. This enhancement is attributed to the formation of a CaZrO3 physical barrier and the synergistic effect of Ce and Sc in suppressing deleterious phase transformations. This study provides an experimental basis for the preparation and application of high-performance TBCs.

Input error is one of the main sources of uncertainty in hydrological models. It mainly comes from the uncertainty of precipitation data, which is caused by inaccurate measurement at the point scale and imperfect representation at the regional scale. The structural error of the hydrological model is dependent on the input, and the uncertainty interaction between the model input and structural will increase the cumulative error of the hydrological process. Therefore, the objective of this study is to investigate the impacts of the uncertainties of rain gauge station input levels and hydrological models on flows with different magnitudes by setting nine input levels of rain gauge stations using three hydrological models (i.e., HyMod, XAJ and HBV). The variance decomposition method based on subsampling was used to dynamically quantify the contribution rates of rain gauge station input levels, hydrological models, and their interaction to the runoff simulation uncertainty. The results show that different rain gauge station input levels and hydrological models dynamically affected the hydrological simulation due to an uneven spatiotemporal distribution of precipitation. Moreover, the simulation accuracy was poor at low flow but better at high flow. Increasing the number of rainfall stations input under a certain threshold could significantly improve the hydrological simulation accuracy. In addition, the contributions of the uncertainties of the rain gauge station input levels and its interaction with the hydrological model to runoff were significantly enhanced in the flood season, but the contribution of the hydrological model uncertainty was still dominant. The results of this study can provide a decision-making basis and scientific guidance for the management and planning of water resources within basins under the influence of a changing environment.

Radix Astragali is commonly used in traditional Chinese medicine, and its quality is closely related to ecological factors, such as climate and soil, in the production area. To provide high-quality Radix Astragali to Chinese and foreign markets, we used maximum entropy model and statistical analysis method, combined with data on ecological factors, Astragalus membranaceus var. mongholicus geographical distribution, and index component content to predict the ecological suitability distribution of A. membranaceus var. mongholicus and establish the relationship between astragaloside IV and calycosin-7-glucoside in this species and ecological factors. Subsequently, we could determine the suitability regionalization of high-quality A. membranaceus var. mongholicus in Inner Mongolia, China. The results showed that the standard deviation of seasonal changes in temperature (40.6%), precipitation in October (15.7%), vegetation type (14.3%), soil type (9.2%), and mean sunshine duration in the growing season (9.1%) were the top five most influential factors out of the 17 main ecological factors affecting the distribution of A. membranaceus var. mongholicus . The standard deviation of seasonal changes in temperature, precipitation in October, precipitation in April, soil pH, and mean sunshine duration in the growing season were found to be the key ecological factors affecting the accumulation of astragaloside IV and calycosin-7-glucoside in A. membranaceus var. mongholicus . The regions with the highest-quality A. membranaceus var. mongholicus were distributed in Baotou (Guyang County), Hohhot (Wuchuan County), and central Wulanchabu (Chahar Right Middle Banner, Chahar Right Back Banner, and Shangdu County) and its surroundings in Inner Mongolia. Baotou, Hohhot, and their surrounding areas were the main traditional production areas of A. membranaceus var. mongholicus , and central Wulanchabu was a potentially suitable distribution area of this species . The main production areas were consistent with the actual production base of A. membranaceus var. mongholicus . This study therefore provides a scientific basis to guide the cultivation of A. membranaceus var. mongholicus .

This paper explains the relationship between public services expenditure and agglomeration economy from the perspective of spatial structure, considering that the allocation of public service expenditure by local governments does not fully leverage the benefits of agglomeration effects. We constructed a general equilibrium model that examines the close relationship between public service expenditure and agglomeration effect. From a spatial structure perspective, regions are categorized into monocentric and polycentric spatial structures. We discussed the scale of urban expansion and the level of public service expenditure in secondary cities across these different types of spatial structures. It was examined 31 provincial capitals of China as research samples to validate the applicability of theoretical mechanism analysis. Six models were constructed using 2S-GMM to investigate the relationship between the public service expenditure and agglomeration effect. Meanwhile, the PTR method was employed to develop 36 models to assess the threshold effect of urban expansion scale and public service expenditure in the second city of the region, focusing on the influence mechanism of public service expenditure allocation on the agglomeration effect. Three noteworthy conclusions are as follows: (1) the scale and structure of public service expenditure has a positive influence on agglomeration effect. (2) in monocentric structure areas, we should focus on the impact of the public services expenditure structure on agglomeration effect in the changes of urban scale. (3) in polycentric structure areas, we should focus on the impact of the public services expenditure structure on agglomeration effect in the changes of scale of public services in the second central city. This research not only have enhanced the theoretical influence mechanism of public service expenditure on the agglomeration effect from the perspective of spatial structure, but also offers guidance on the allocation of public service expenditure in provincial capital cities.

Continental shale oil fracturing dynamics are governed by interactions between hydraulic fractures and pre-existing natural fractures. This study establishes a fluid–solid coupling model using globally embedded cohesive elements to simulate fracture propagation in naturally fractured reservoirs. Key factors affecting fracture network complexity were quantified: (1) Weakly cemented natural fractures (bond strength coefficient <0.5) promote 23% higher fracture tortuosity compared to strongly cemented formations. (2) Optimal horizontal stress differentials (Δσ = 8–10 MPa) balance fracture length (increased by 35–40%) and branching complexity. (3) Injection rate elevation from 0.06 to 0.132 m3/min enhances the stimulated volume by 90% through improved fracture dimensions. The findings provide mechanistic insights for optimizing fracture network complexity in shale reservoirs.

Previous studies of injection-induced earthquake sequences have shown that the maximum magnitude (M ) of injection-induced seismicity increases with the net injected volume (V); however, different proposed seismic-hazard paradigms predict significantly different values of M . Using injection and seismicity data from two project areas in northeastern British Columbia, Canada, where hydraulic fracturing induced seismicity was observed, we test the predictive power and robustness of three existing and one novel method to estimate M . Due to their vastly different values of seismogenic index (Σ), these two project areas represent end-member cases of seismogenic response. Our novel method progressively adjusts the M forecast under the assumption that each recorded event embodies an incremental release of fluid-induced stress. The results indicate that our method typically provides the lowest upper bound of the tested methods and it is less sensitive to site-specific calibration parameters such as Σ. This makes the novel method appealing for operational earthquake forecasting schemes as a real-time mitigation strategy to manage the risks of induced seismicity.

Sphingosine-1-phosphate (S1P) is an important bioactive lipid molecule in cell membrane metabolism and binds to G protein-coupled S1P receptors (S1PRs) to regulate embryonic development, physiological homeostasis, and pathogenic processes in various organs. S1PRs are lipid-sensing receptors and are therapeutic targets for drug development, including potential treatment of COVID-19. Herein, we present five cryo-electron microscopy structures of S1PRs bound to diverse drug agonists and the heterotrimeric Gi protein. Our structural and functional assays demonstrate the different binding modes of chemically distinct agonists of S1PRs, reveal the mechanical switch that activates these receptors, and provide a framework for understanding ligand selectivity and G protein coupling.

IntroductionThe economic value realization of blue carbon is crucial for promoting ocean sustainable development and addressing global climate change. In today's blue carbon development context, the synergy between green finance and technological innovation is increasingly prominent, serving as a key channel to activate the latent value of blue carbon resources.MethodsThis study examines the coupling of green finance and technological innovation in nine Chinese coastal provinces from 2005 to 2021 by constructing an indicator system and a coupling coordination model, and analyzes how they jointly enhance marine carbon sink value.ResultsResearch findings reveal that the interaction between green finance and technological innovation exhibits a U-shaped effect on realizing marine carbon sink value. Specifically, the U-shaped influence of the coupling coordination degree between green finance and technological innovation on marine carbon sink value is mediated through marine carbon sink efficiency and marine aquaculture structure. Moreover, this influence exhibits distinct regional heterogeneity.DiscussionBased on these findings, this paper proposes policy recommendations to formulate differentiated green finance policies, innovate marine carbon sink financial instruments, and promote corporate technological synergy and management optimization. These measures aim to enhance the synergistic effects between green finance and technological innovation, thereby further unlocking the potential for marine carbon sequestration.

Thoracic aortic aneurysm (TAA) is a localized or diffuse dilatation of the thoracic aortas, and causes many sudden deaths each year worldwide. However, there is no effective pharmacologic therapy. Here, we show that AGGF1 effectively blocks TAA-associated arterial inflammation and remodeling in three different mouse models (mice with transverse aortic constriction, Fbn1 C1041G/+ mice, and β-aminopropionitrile-treated mice). AGGF1 expression is reduced in the ascending aortas from the three models and human TAA patients. Aggf1 +/- mice and vascular smooth muscle cell (VSMC)-specific Aggf1 smcKO knockout mice show aggravated TAA phenotypes. Mechanistically, AGGF1 enhances the interaction between its receptor integrin α7 and latency-associated peptide (LAP)-TGF-β1, blocks the cleavage of LAP-TGF-β1 to form mature TGF-β1, and inhibits Smad2/3 and ERK1/2 phosphorylation in VSMCs. Pirfenidone, a treatment agent for idiopathic pulmonary fibrosis, inhibits TAA-associated vascular inflammation and remodeling in wild type mice, but not in Aggf1 +/- mice. In conclusion, we identify an innovative AGGF1 protein therapeutic strategy to block TAA-associated vascular inflammation and remodeling, and show that efficacy of TGF-β inhibition therapies require AGGF1. Thoracic aortic aneurysm (TAA) causes many sudden deaths each year, however, no effective drug treatment is available. Here, the authors show that AGGF1 protein therapy attenuates TAA in three different mouse models through integrin α7-mediated inhibition of TGF-β1 maturation and ERK1/2 signalling.

Previous studies attempting to quantify the contributions of climate change and human activities to runoff variations in a changing environment have widely focused on an annual scale, while seasonal scales are rarely involved. China is the largest socialist country in the world, and its economic development is affected by its Five-year Plan policy. To this end, the upper Han River Basin, the largest tributary of the Yangtze River Basin, was selected as a case study. A seasonal-scale Budyko framework was extended based on the monthly abcd model in this study for quantifying the effects of climate and human activities changes on seasonal runoff variations, especially exploring the effect of China’s Five-year Plan policy. Results disclose that: (1) the change point in the annual runoff series is 1990, and the monthly abcd model achieves good performance in the prechange and postchange period; (2) the relative contribution of climate change to runoff variations is 62.99%, 70.20%, 87.54%, and 90.30% in spring, summer, autumn, and winter, respectively, indicating that climate change is the dominant factor controlling runoff variations in every season; (3) the contributions of climate change and human activities show obvious dynamic and seasonal characteristics, which are strongly impacted by the implementation of the Five-year Plan policy. Generally, the findings of this study provide valuable references for local reasonable water resource planning and management to make timely and appropriate use of the water supply.