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The service performance of welded parts is directly impacted by the microstructure of the Inconel 718 welded joint； however， there is a lack of comprehensive research on the impact of the Mn element on the microstructure and perfor⁃ mance of the welded junction. In this study， the solid-solution Inconel 718 hot-rolled plates with varied Mn concentrations of

The effects of 0.0001%，0.0018% and 0.0037% S content on the solidification characteristics of K417G alloy were studied by isothermal solidification experiment in the temperature range of 1340-1230 ℃. The results show that S can reduce the solidus temperature of the alloy and enlarge the solid-liquid two phase region. When the S content increases from 0.0001% to 0.0037%， the solidus temperature of the alloy decreases from 1255 ℃ to 1245 ℃. During the solidification process， the S element segregates in the liquid phase and precipitates out as the Y phase in the final solidification zone. And S promotes the enrichment of Al and Cr elements at the solid-liquid interface. At the same isothermal temperature， the increase of S content promotes the increase of the volume fraction of MC carbide，γ+γ΄ eutectic and Y phase， and has little effect on the morphology and precipitation temperature of MC carbide and γ+γ΄ eutectic， but the precipitation temperature of the Y phase is increased from 1230 ℃ to 1240 ℃.

Increased secretion of exosomes in precancerous lesions of hepatocellular carcinoma can directly promote the disease from inflammatory response to cancer through intercellular communication. Exosomes participate in the occurrence and development of hepatocellular precancerous lesions by affecting angiogenesis, epithelial-mesenchymal transition and immunoregulation,so exomes may become a new therapeutic target for hepatocellular precancerous lesions and provide new ideas for the diagnosis and treatment of hepatocellular carcinomas.

Titanium dioxide nanoparticles (TiO2 NPs) can cause apoptosis in TM4 cells; however, the underlying mechanism has not been entirely elucidated. The purpose of this study was to investigate the effects of TiO2 NPs on ROS, Ca2+ level, p38/AKT/mTOR pathway, and apoptosis in TM4 cells and to evaluate the role of Ca2+ in p38/AKT/mTOR pathway and apoptosis. After exposure to different concentrations (0, 50, 100, 150, and 200 μg/mL) of TiO2 NPs for 24 h, cell viability, ROS, Ca2+ level, Ca2+‐ATPase activity, p38/AKT/mTOR pathway‐related proteins, apoptosis rate, and apoptosis‐related proteins (Bax, Bcl‐2, Caspase 3, Caspase 9, and p53) were detected. The ROS scavenger NAC was used to determine the effect of ROS on Ca2+ level. The Ca2+ chelator BAPTA‐AM was used to evaluate the role of Ca2+ in p38/AKT/mTOR pathway and apoptosis. TiO2 NPs significantly inhibited cell viability, increased ROS level, and elevated Ca2+ level while suppressing Ca2+‐ATPase activity. TiO2 NPs regulated the p38/AKT/mTOR pathway via increasing p‐p38 level and decreasing p‐AKT and p‐mTOR levels. TiO2 NPs significantly enhanced the apoptosis. NAC attenuated Ca2+ overload and reduction in Ca2+‐ATPase activity caused by TiO2 NPs. BAPTA‐AM alleviated TiO2 NPs‐induced abnormal expression of p38/AKT/mTOR pathway‐related proteins. BAPTA‐AM assuaged the apoptosis caused by TiO2 NPs. Altogether, this study revealed that TiO2 NPs elevated intracellular Ca2+ level through ROS accumulation. Subsequently, the heightened intracellular Ca2+ level was observed to exert regulation over the p38/AKT/mTOR pathway, ultimately culminating in apoptosis. These results provides a complementary understanding to the mechanism of TiO2 NPs‐induced apoptosis in TM4 cells. We investigated the relation between ROS, Ca2+, and p38/AKT/mTOR pathway in TiO2 NPs‐induced apoptosis of TM4 cells. TiO2 NPs prompted an excessive accumulation of Ca2+ through ROS‐mediated mechanisms. Additionally, Ca2+ overload was found to modulate the p38/AKT/mTOR pathway, leading to apoptosis in TM4 cells via the mitochondrial pathway. [ABSTRACT FROM AUTHOR]

Communities in dryland ecosystems face multiple stressors that threaten their livelihood resilience. While community resilience in socio‐ecological systems is largely determined by access to and sustainable management of natural resources, the underlying mechanisms are still poorly understood. This study, which uses grounded theory integrated with discourse analysis, aims to contribute addressing this knowledge gap. First, we explore global literature describing trends and patterns in the various stressors—including climate change, frequent drought, and famine, ecological, socio‐economic, and institutional stressors—that impact the livelihood resilience of these communities, with the goal of summarizing how multiple stressors impact the sustainability of dryland social‐ecological systems. Then, using the sustainable development goals (SDGs) as a reference target, we propose potential entry points to support livelihood resilience pathways. These include land, water, livestock and agroforestry, and institutional and social capital. Lastly, we suggest an integrated multi‐scalar pathway embedded with cross‐sectorial policies and differential cross‐social strategies towards combining resilience with SDGs targets. This research can help stakeholders to adapt to and mitigate the impacts of various stressors, ultimately strengthening livelihood resilience in dryland ecosystems. [ABSTRACT FROM AUTHOR]

Bi-based halide perovskites have the characteristics of low toxicity, air stability, long carrier diffusion lifetime, and large light absorption coefficient, making them promising candidates for imaging sensors. However, existing approaches for preparing arrays still have challenges due to the sensitivity of Bi-based perovskites to polar solvents. Herein, we present 25 × 25 array devices based on Cs3Bi2Br9/GaN photodetectors (PDs) using a laser-scribing technique, which has the advantages of low cost, high accuracy, and being lithography-free. The optimized Cs3Bi2Br9/GaN PD showed outstanding self-powered photodetection capability with an ultralow dark current of 10−12 A under zero bias. Notably, the device exhibits remarkably weak light detection capability, enabling effective detection under 13.4 nW cm−2 illumination. In addition, the unencapsulated PD can maintain 95.1% of its initial performance after 5000 cycles of consecutive operation, and the device can perfectly follow light signals of different waveforms even after 3 months of storage in air, proving its excellent working stability. Finally, the arrays were used as sensors in an imaging system, and high-resolution imaging patterns were obtained. The results highlight a simple method for the fabrication of high-resolution imaging sensors and are expected to promote the development of low-cost and reliable imaging sensors. [ABSTRACT FROM AUTHOR]

With the extensive application of titanium dioxide nanoparticles (TiO2 NPs), their impacts on calcium homeostasis have aroused extensive attention from scholars. However, there are still some controversies in relevant reports. Therefore, a systematic review was performed followed by a meta-analysis to explore whether TiO2 NPs could induce the imbalance in calcium homeostasis in vivo and in vitro through Revman5.4 and Stata15.0 in this research. Fourteen studies were included through detailed database retrieval and literature screening. Results indicated that the calcium levels were significantly increased and the activity of Ca2+-ATPase was significantly decreased by TiO2 NPs in vivo and in vitro. Subgroup analysis of the studies in vivo showed that TiO2 NPs exposure caused a significant increase in calcium levels in rats, exposure to large-sized TiO2 NPs (>10 nm) and long-term (>30 days) exposure could significantly increase calcium levels, and the activity of Ca2+-ATPase showed a concentration-dependent downward trend. Subgroup analysis of the studies in vitro revealed that intracellular calcium levels increased significantly in animal cells, exposure to small-sized TiO2 NPs (≤10 nm) and high concentration (>10 μg/mL) exposure could induce a significant increase in Ca2+ concentration, and the activity of Ca2+-ATPase also showed a concentration-dependent downward trend. This research showed that the physicochemical properties of TiO2 NPs and the experimental scheme could affect calcium homeostasis [ABSTRACT FROM AUTHOR]