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Three-dimensional (3D) extrusion-based bioprinting is the most widely used bioprinting technology to fabricate bionic tissue or organ constructs by combining biomaterial ink and living cells for tissue engineering and regenerative medicine. One critical issue of this technique is the selection of suitable biomaterial ink to simulate extracellular matrix (ECM) that provides mechanical support for cells and regulates their physiological activities. Previous studies have demonstrated that it is an enormous challenge to form and maintain reproducible 3D constructs and eventually achieve the balance among biocompatibility, mechanical properties, and printability. This review highlights the properties of extrusion-based biomaterial inks and recent developments as well as details various biomaterial inks classified by their function. Key approaches related to their modification methods according to the functional requirements are also discussed, along with the selection strategies by varying extrusion paths and methods in extrusion-based bioprinting. This systematical review will assist researchers in identifying the most suitable extrusion-based biomaterial inks based on their requirements, as well as in elaborating current challenges and prospects of extrudable biomaterial inks in the field of bioprinting of in vitro tissue models., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright: © 2023 Li X, Zheng F, Wang X, et al.)

Historical sources describe irrigation and intensive agriculture being practiced in lowland Yunnan from at least the first century AD, but so far archaeobotanical remains allowing investigation of this issue have been scarce. Here, we present new archaeobotanical evidence, including macro-botanical and phytoliths results, from the Dian settlement site of Dayingzhuang, with direct AMS radiocarbon dates on two wheat grains falling between 750 and 390 BC. We compare these results with contemporary Dian sites and analyse the agricultural systems in Central Yunnan between the eight and fourth centuries BC. We propose that agriculture was intensified toward the end of the Dian through both multiple cropping seasons and increased evidence for irrigated rice fields., Supplementary Information: The online version contains supplementary material available at 10.1007/s12520-020-01268-y., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Author(s) 2021.)