Abstract: Described herein are apparatuses, systems, and methods for fabricating tissue constructs, such as by fabricating perfusable tissue constructs by embedding a sacrificial material into a composite matrix yield stress support bath. A composite matrix bath can include a microgel filler and a hydrogel precursor. An extrusion tip can be used for embedded printing of perfusable tissue constructs by disposing sacrificial material into the composite matrix bath while the extrusion tip travels along a predefined course through the composite matrix bath. This sacrificial material can be the printed tissue construct or can be removed to render the matrix bath a perfusable tissue construct. The composite matrix bath can include acellular or cell-laden hydrogels. The sacrificial material can include a salt and a physiological buffer or a non-cytotoxic porogen material. The hydrogel precursor can include at least one of gellan and gelatin. Cross-linking can be carried out chemically, thermally, enzymatically, or physically.

Abstract: Described herein are injectable composite inks composed of a hydrogel continuous phase with a plurality of microgels present within the hydrogel continuous phase. The inks described herein have unique chemical and physical properties that enable them to be printed into a number of different types of articles. The articles produced by the injectable composite inks have numerous medical applications.

Abstract: A conveying system, comprising: a conveying carrier (3) that is provided with a first connection structure (31); a rolling bed (1) that comprises a rolling bed base (11) and a plurality of rolling components (12), wherein the rolling components (12) are connected to the rolling bed base (11); a driving mechanism comprising a second connection structure (26) and a driving assembly, wherein the driving assembly can drive the second connection structure (26) to reciprocate between a first position and a second position along a conveying direction, the second connection structure (26) at the first position is connected to the first connection structure (31), and the second connection structure (26) at the second position is separated from the first connection structure (31); and a positioning mechanism (4) comprising an X-direction positioning assembly, a Y-direction positioning assembly, and a Z-direction positioning assembly, wherein the Z-direction positioning assembly lifts the conveying carrier (3), so that