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Efficient synthesis of large-scale vertically aligned nitrogen-doped carbon nanotube arrays (VA-NCNTs) has always been a challenge. In this study, we proposed a facile way to obtain mass VA-NCNTs between vermiculite layers by horizonal chemical vapor deposition (CVD). Vermiculite with layered compound as the catalyst substrate, Fe and Mo as the active metal phase is evenly distributed between the vermiculite layers, melamine is pyrolyzed as a single source for both carbon and nitrogen to synthesize nitrogen-doped carbon nanotube (CNT) array materials with relatively uniform length and diameter at an optimum temperature of 800 °C. We explored the effect of temperature on synthesis of VA-NCNTs, the results indicated that the VA-NCNTs are sensitive to temperature changes during the CVD synthesis process, the arrangement, diameter, nitrogen content, and the type of nitrogen function of CNTs could be modified. This work contributes to the study of how the growth temperature affecting the morphology of the as-prepared CNTs, and provides a potential method for the controllable mass production of oriented NCNTs. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) derived from cancer cells are crucial mediators of intercellular communication during tumor progression. The cargo in tumor-derived EVs that facilitates the establishment of a tumor-supportive microenvironment could serve as a therapeutic target to improve cancer treatment. Here, we demonstrated that hepatocellular carcinoma (HCC) cells secreted the acyl-CoA synthetase ACSL4 in large extracellular vesicles (lEVs) to modulate tumor-microenvironment interactions that promote HCC progression. HCC-derived lEV ACSL4 increased the intracellular abundance of polyunsaturated fatty acid-containing lipids and remodeled the lipid profile to potentiate lipid peroxidation in peritumoral hepatocytes, resulting in hepatocyte senescence accompanied by the senescence-associated secretory phenotype (SASP). Depletion of senescent hepatocytes by senolytic treatment suppressed tumor progression. In HCC cells, SREBP2-mediated transcriptional activation upregulated ACSL4 expression, and Akt-mediated phosphorylation of ACSL4 induced its packaging into lEVs by augmenting its interaction with Annexin A2. This study identified the critical regulatory function of ACSL4 secreted from HCC cells in inducing lipid remodeling and senescence in hepatocytes to support HCC progression, suggesting that targeting lEV ACSL4 is a potential therapeutic strategy for HCC.

Inorganic chalcogenides containing cations with lone-pair electrons have attracted considerable attention because of their potential applications in photocatalysis. In this research, two new copper thioarsenates with the lowest Cu-to-As ratio in the quaternary X/Cu/As/Q (X = inorganic cations; Q = chalcogen) system, namely Cs 3 CuAs 4 Q 8 (Q = S, Se), were obtained by a simple surfactant-thermal method at a low temperature. These two isostructural compounds belong to the monoclinic space group C 2/ c (no. 15) and are composed charge-balanced Cs + cations and two-dimensional anionic [CuAs 4 Q 8 ] 3- layers. Notably, photo-electrochemical measurements indicate that Cs 3 CuAs 4 Q 8 possesses a remarkable photocurrent response under simulated solar-light illumination. Further theoretical studies were performed to gain insights into the relationships between electronic structure and optical properties.