Deep Learning for Size-Agnostic Inverse Design of Random-Network 3D Printed Mechanical Metamaterials

Practical applications of mechanical metamaterials often involve solving inverse problems aimed at finding microarchitectures that give rise to certain properties. The limited resolution of additive manufacturing techniques often requires solving such inverse problems for specific specimen sizes. Moreover, the candidate microarchitectures...

Deep learning for the rare-event rational design of 3D printed multi-material mechanical metamaterials

Emerging multi-material 3D printing techniques enables the rational design of metamaterials with not only complex geometries but also arbitrary distributions of multiple materials within those geometries, yielding unique combinations of elastic properties. However, discovering the rare designs that lead to highly unusual combinations of...

Nuclear factor erythroid 2–related factor 2 (Nrf2) deficiency causes age-dependent progression of female osteoporosis

Background: Nuclear factor erythroid 2–related factor 2 (Nrf2) is a crucial transcription factor for cellular redox homeostasis. The association of Nrf2 with elderly female osteoporotic has yet to be fully described. The aim was to elucidate a potential age-dependent Nrf2 contribution to female osteoporosis in mice. Methods: Eighteen female...

Semi-automated digital workflow to design and evaluate patient-specific mandibular reconstruction implants

The reconstruction of large mandibular defects with optimal aesthetic and functional outcomes remains a major challenge for maxillofacial surgeons. The aim of this study was to design patient-specific mandibular reconstruction implants through a semi-automated digital workflow and to assess the effects of topology optimization on the...

Spiral honeycomb microstructured bacterial cellulose for increased strength and toughness

Natural materials, such as nacre and silk, exhibit both high strength and toughness due to their hierarchical structures highly organized at the nano-, micro-, and macroscales. Bacterial cellulose (BC) presents a hierarchical fibril structure at the nanoscale. At the microscale, however, BC nanofibers are distributed randomly. Here, BC self...

Non-affinity in multi-material mechanical metamaterials

Non-affine deformations enable mechanical metamaterials to achieve their unusual properties while imposing implications for their structural integrity. The presence of multiple phases with different mechanical properties results in additional non-affinity of the deformations, a phenomenon that has never been studied before in the area of...

Auxeticity and stiffness of random networks: Lessons for the rational design of 3D printed mechanical metamaterials

The emergence of advanced 3D printing techniques and the recent interest in architected materials have sparked a surge of interest in mechanical metamaterials whose unusual properties are defined by their highly ordered microarchitectures. Mechanical metamaterials with disordered microarchitectures have, however, not received as much...

Multi-material 3D printed mechanical metamaterials: Rational design of elastic properties through spatial distribution of hard and soft phases

Up until recently, the rational design of mechanical metamaterials has usually involved devising geometrical arrangements of micro-architectures that deliver unusual properties on the macro-scale. A less explored route to rational design is spatially distributing materials with different properties within lattice structures to achieve the...