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Continuous flow synthesis is pivotal in dye production to address batch‐to‐batch variations. However, synthesizing water‐insoluble dyes in an aqueous system poses a challenge that can lead to clogging. This study successfully achieved the safe and efficient synthesis of azo dyes by selecting and optimizing flow reactor modules for different reaction types in the two‐step reaction and implementing cascade cooperation. Integrating continuous flow microreactor with continuous stirred tank reactor (CSTR) enabled the continuous flow synthesis of Sudan Yellow 3G without introducing water‐soluble functional groups or using organic solvents to enhance solubility. Optimizing conditions (acidity/alkalinity, temperature, residence time) within the initial modular continuous flow reactor resulted in a remarkable 99.5% isolated yield, 98.6 % purity, and a production rate of 2.90 g h−1. Scaling‐up based on different reactor module characteristics further increased the production rate to 74.4 g h−1 while maintaining high yield and purity. The construction of this small 3D‐printing modular cascaded reactor and process scaling‐up provide technical support for continuous flow synthesis of water‐insoluble dyes, particularly high‐market‐share azo dyes. Moreover, this versatile methodology proves applicable to continuous flow processes involving various homogeneous and heterogeneous reaction cascades. [ABSTRACT FROM AUTHOR]

Intervertebral disc degeneration (IDD) is one of the main causes of low back pain, which affects the patients' quality of life and health and imposes a significant socioeconomic burden. Despite great efforts made by researchers to understand the pathogenesis of IDD, effective strategies for preventing and treating this disease remain very limited. Sirtuins are a highly conserved family of (NAD+)‐dependent deacetylases in mammals that are involved in a variety of metabolic processes in vivo. In recent years, sirtuins have attracted much attention owing to their regulatory roles in IDD on physiological activities such as inflammation, apoptosis, autophagy, aging, oxidative stress, and mitochondrial function. At the same time, many studies have explored the therapeutic effects of sirtuins‐targeting activators or micro‐RNA in IDD. This review summarizes the molecular pathways of sirtuins involved in IDD, and summarizes the therapeutic role of activators or micro‐RNA targeting Sirtuins in IDD, as well as the current limitations and challenges, with a view to provide possible solutions for the treatment of IDD. [ABSTRACT FROM AUTHOR]

State-of-the-art multidimensional catalysts have been developed to realize high-performance proton exchange membrane fuel cells (PEMFCs). However, local oxygen transport resistance significantly limits the catalytic performance of catalysts in actual PEMFC application. Therefore, we comprehensively investigated the ionomer film morphologies and local oxygen transport mechanisms near representative multidimensional catalysts with various structures to reveal the effect of catalyst structures on local oxygen transport. We demonstrate that the one-dimensional nanowire structure of catalysts shows a much lower local oxygen transport resistance than three-dimensional ones owing to broader and shorter oxygen transport paths in well-layered ionomer films on one-dimensional catalysts. Moreover, the core–shell and hollow structures of catalysts achieve local oxygen transport capacity identical to the solid one while greatly reducing platinum usage. Therefore, the one-dimensional core–shell or hollow structures of catalysts can highly reduce local oxygen transport resistance in PEMFCs with low platinum usage. The findings are valuable for catalyst designs to achieve low local oxygen transport in actual PEMFC application. [ABSTRACT FROM AUTHOR]

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