Chronic inflammation-induced metastases have long been regarded as one of the significant obstacles in treating cancer. Tumor necrosis factor-α (TNF-α), a main inflammation mediator within tumor microenvironment, affects tumor development by inducing multiple chemokines to establish a complex network. Recent reports have revealed that CXCL10/CXCR3 axis affects cancer cells invasiveness and metastases, and Epithelial-mesenchymal transition (EMT) is the main reason for frequent proliferation and distant organ metastases of colon cancer (CC) cells, However, it is unclear whether TNF-α-mediated chronic inflammation can synergically enhance EMT-mediated CC metastasis through promoting chemokine expression. According to this study, TNF-α activated the PI3K/Akt and p38 MAPK parallel signal transduction pathways, then stimulate downstream NF-κB pathway p65 into the nucleus to activate CXCL10 transcription. CXCL10 enhanced the metastases of CC-cells by triggering small GTPases such as RhoA and cdc42. Furthermore, overexpression of CXCL10 significantly enhanced tumorigenicity and mobility of CC cells in vivo. We further clarified that CXCL10 activated the PI3K/Akt pathway through CXCR3, resulting in suppression of GSK-3β phosphorylation and leading to upregulation of Snail expression, thereby regulating EMT in CC cells. These outcomes lay the foundation for finding new targets to inhibit CC metastases.

Exploiting advanced electrocatalysts for the sluggish oxygen reduction reaction (ORR) of the cathode is greatly crucial for proton-exchange membrane fuel cell (PEMFC) commercial application but still exhibit a significant challenge, especially the stability issues that have drawn attractive attention. Therefore, we introduced a nitrogen-doped carbon layer into the Pt/C surface, which not only prevents aggregation of Pt nanoparticles but also endows the electrocatalyst with enhanced performance without hiding the internal Pt active sites. The accelerated durability tests show an ignorable ORR activity loss (10 mV) in the as-prepared Pt/C@NC-0.06 sample compared to the pristine Pt/C catalyst (37 mV) after 5000 cyclic voltammetry cycles. Furthermore, in comparison to the pristine Pt/C catalyst (0.28 mA cm–2), the as-obtained Pt/C@NC-0.06 sample exhibits 2.32-fold improvement for the specific activity. The enhanced ORR properties of the Pt/C@NC-X catalyst in this work supplies a promising way to facilitate the electrocatalytic performance of catalysts in PEMFCs.

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Improving the activity and stability of Pt‐based electrocatalysts is essential for large‐scale commercial applications of fuel cells. The ordered Pt‐based alloy nanomaterials encapsulated by coating have attracted significant attention. Here, we displayed a surface coating strategy to synthesize structurally ordered PtCo alloy catalysts featuring nitrogen‐doped carbon (NC). Experimental results reveal that the sample with appropriate dopamine feeding content shows enhanced oxygen reduction activity and stability, which exhibits a mass activity of 1.36 mA ⋅ mg−1Pt and specific activity of 1.98 mA ⋅ cm−2, superior to those of excessive or low dopamine adding content samples and commercial Pt/C catalyst. The enhanced electrocatalytic performance of this catalyst was attributed to the combined effect including the protection of suitable thickness NC shells, strong electronic interaction and high ordering degree. In this work, the surface coating strategy provides available references to further improve the oxygen reduction performance of PtM alloy catalysts.

The high cost and deficiency of long-term durability of carbon supported Pt catalysts have been regarded as obstacle that impeding their practical proton exchange membrane fuel cells (PEMFCs) technologies. Furtherly, iron and nitrogen co-doped carbons (Fe/NC) are emerging as a steady electrocatalyst. Unfortunately, there are less-active sites in acidic electrolyte. Herein, combining the advantages of Fe/NC and Pt catalysts, we propose an in-situ surfactant-free self-templating solution reduction strategy to construct Pt nanoparticles (NPs) onto well-devised Fe/NC porous nanostructures in order to manufacture highly performing PtÀ Fe/NC catalyst for oxygen reduction reaction (ORR). The obtained PtÀ Fe/NC catalyst displays excellent ORR performance, realizing an account of 2.53 improvement in specific activity and an account of 1.20 strengthening in mass activity toward ORR compared to the commercial Pt/C catalysts. Stability tests confirm that the assynthesized PtÀ Fe/NC catalyst is more electrochemically steady than the commercial Pt/C catalysts on account of the electronic interaction between Pt and N which result from the difference in electronegativity. Our work provides a promising strategy for exploring the accomplishment of better ORR in acid electrolytes.

Coal and coal by-products are considered as the potential raw materials for critical elements (e.g., rare earth elements, Li, Ga, Ge, etc.), which have attracted much attention in recent years. The purpose of this study is to investigate the mineralogical and geochemical characteristics, and controlling geological factors of lithium and rare earth elements in the Lopingian (Wujiaping Formation) coal from the Donggou Mine, southeastern Chongqing Coalfield, China. Results indicate that lithium and rare earth elements are significantly enriched in the Donggou coals, which could be new potential alternative sources for critical elements. Concentrations of lithium and rare earth elements in the Donggou coals gradually increase from top to bottom. Lithium is mainly associated with kaolinite, while rhabdophane, florencite, goyazite, and xenotime are the main hosts of rare earth elements. The controlling geological factor is the groundwater leaching of underlying tuff, and to a lesser extent, the terrigenous clastic materials input from the top layer of the Kangdian Upland. This study provides mineralization information for lithium and rare earth elements exploration in coal measures.

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