Xufeng Yin

1. Introduction With the rapid development of science and technology, human exploration of space has progressed from the initial exploration of near-Earth space to the current exploration of deep space. In the process of exploring the universe, a variety of space launch vehicles have been developed, such as airships, airplanes, space shuttles, rockets, starships, and so on. The above space launch vehicles are simply huge fuel storage tanks containing a large amount of liquid or solid fuel.

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1. Introduction Keloids are a fibroproliferative disorder, characterized by abnormal proliferation of fibroblasts and excessive deposition of extracellular matrix (ECM) [1]. Usually benign, they may still grow aggressively beyond their original boundary, causing deformity, itching, pain, and functional or even psychological disorders [1].