by Keyword: Topological defects
Velez-Ceron, Ignasi, Guillamat, Pau, Sagues, Francesc, Ignes-Mullol, Jordi, (2024). Probing active nematics with in situ microfabricated elastic inclusions Proceedings Of The National Academy Of Sciences Of The United States Of America 121, e2312494121 
In this work, we report a direct measurement of the forces exerted by a tubulin/kinesin active nematic gel as well as its complete rheological characterization, including the quantification of its shear viscosity, lb and its activity parameter, a. For this, we develop a method that allows us to rapidly photo -polymerize compliant elastic inclusions in the continuously remodeling active system. Moreover, we quantitatively settle longstanding theoretical predictions, such as a postulated relationship encoding the intrinsic time scale of the active nematic in terms of n and a. In parallel, we infer a value for the nematic elasticity constant, K, by combining our measurements with the theorized scaling of the active length scale. On top of the microrheology capabilities, we demonstrate strategies for defect encapsulation, quantification of defect mechanics, and defect interactions, enabled by the versatility of the microfabrication strategy that allows to combine elastic motifs of different shapes and stiffnesses that are fabricated in situ.
JTD Keywords: Dynamics, Hydrogel, Micro fabricatio, Motio, Rheology, Soft active matter, Topological defects
Matejcic, M, Trepat, X, (2023). Mechanobiological approaches to synthetic morphogenesis: learning by building Trends In Cell Biology 33, 95-111
Tissue morphogenesis occurs in a complex physicochemical microenvironment with limited experimental accessibility. This often prevents a clear identification of the processes that govern the formation of a given functional shape. By applying state-of-the-art methods to minimal tissue systems, synthetic morphogenesis aims to engineer the discrete events that are necessary and sufficient to build specific tissue shapes. Here, we review recent advances in synthetic morphogenesis, highlighting how a combination of microfabrication and mechanobiology is fostering our understanding of how tissues are built.Copyright © 2022 Elsevier Ltd. All rights reserved.
JTD Keywords: cell dynamics, elongation, endothelial-cells, epithelium, growth, lumen, mechanical tension, patterns, self-organization, synthetic morphogenesis, tissue folding, tissue mechanics, topological defects, Cell dynamics, Humans, Morphogenesis, Stem-cells, Synthetic morphogenesis, Tissue folding, Tissue mechanics, Tissue shape
