NSRRC Activity Report 2023

038 NSRRC ACTIVITY REPORT 2023 information on how structural variations of cell walls are tailored for different biological functions. Furthermore, this study also solved a thousand-year-old mystery regarding the most valuable musical instrument in Chinese culture—the guqin zither. Back in the Tang dynasty, a famous guqin maker once said, “Five centuries of aging is required for optimal acoustic properties.” For more than a millennium, guqin makers have wondered how aging promoted wood transformations. The research team showed that as hemicellulose spontaneously degrades over time, CMFs would form dimeric aggregates, accompanied by increases in SAXS cross-section areas but not XRD crystallite widths. The breakdown of hemicellulose matrixes and formation of CMF dimers would alter how sound waves propagate through wood fibers, giving antique guqin a rounded tone and rich harmonics. (Reported by Cheng- Si Tsao, National Taiwan University, and Hwan-Ching Tai, Xiamen University, China) Fig. 1 : Proposed structural models of the hierarchical CMF structure in wood cell walls. (a) Most wood CMFs originate from the S2 layer of longitudinal cells with a core–shell structure. (b) A monoclinic unit cell of cellulose Iβ. (c) CMF models with 18, 24, and 30 chains, each showing just one of many possible configurations. (d) Horizontal cross-section of a CMF pair in fusion and aggregation states. (e) Vertical cross-section of a CMF pair in segregation, partial fusion, and partial aggregation states. [Reproduced from Ref. 1] This report features the work of Cheng-Si Tsao, Hwan-Ching Tai, and their collaborators published in Nat. Plants 9 , 1154 (2023). TPS 13A Biological Small-angle X-ray Scattering TLS 23A Small/Wide Angle X-ray Scattering TLS 01C2 X-ray Powder Diffraction • GIWAXS, GISAXS, WAXS, SAXS, and XRD • Chemistry, Materials Science Reference 1. H.-C. Tai, C.-H. Chang, W. Cai, J.-H. Lin, S.-J. Huang, Q.-Y. Lin, E. C.-Y. Yuan, S.-L. Li, Y.-C. J. Lin, J. C. C. Chan, C.-S. Tsao, Nat. Plants 9 , 1154 (2023).