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Roll-to-roll fabrication setup for self-folding films has been developed to enable high-throughput production of three-dimensional self-folding microstructures, a significant step towards successful commercialization. 

The indirect exchange interaction between local magnetic moments via surface electrons has been long predicted to bolster the surface ferromagnetism in magnetic topological insulators (MTIs), which facilitates the quantum anomalous Hall effect. This unconventional effect is critical to determining the operating temperatures of future topotronic devices. However, the experimental confirmation of this mechanism remains elusive, especially in intrinsic MTIs. Here, we combine time-resolved photoemission spectroscopy with time-resolved magneto-optical Kerr effect measurements to elucidate the unique electromagnetism at the surface of an intrinsic MTI MnBi₂Te₄. Theoretical modeling based on 2D Ruderman-Kittel-Kasuya-Yosida interactions captures the initial quenching of a surface-rooted exchange gap within a factor of two but overestimates the bulk demagnetization by one order of magnitude. This mechanism directly explains the sizable gap in the quasi-2D electronic state and the nonzero residual magnetization in even-layer MnBi₂Te₄. Furthermore, it leads to efficient light-induced demagnetization comparable to state-of-the-art magnetophotonic crystals, promising an effective manipulation of magnetism and topological orders for future topotronics. 

Abstract Rapidly expanding biopharmaceutical market demands more cost‐effective platforms to produce protein therapeutics. To this end, novel approaches, such as perfusion culture or concentrated fed‐batch, have been explored for higher yields and lower manufacturing costs. Although these new approaches produced promising results, but their wide‐spread use in the industry is still limited. In this study, a dialysis rolled scaffold bioreactor was presented for long‐term production of monoclonal antibodies with reduced media consumption. Media dialysis can selectively remove cellular bio‐wastes without losing cells or produced recombinant proteins. The dialysis process was streamlined to significantly improve its efficiency. Then, extended culture of recombinant CHO cells for 41 days was successfully demonstrated with consistent production rate and minimal media consumption. The unique configuration of the developed bioreactor allows efficient dialysis for media management, as well as rapid media exchange to harvest produced recombinant proteins before they degrade. Taken together, it was envisioned that the developed bioreactor will enable cost‐effective and long‐term large‐scale culture of various cells for biopharmaceutical production.