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Researchers at Rice University in Texas have developed a sustainable method for 3D printing using ink made from recycled wood. By breaking down leftover wood into lignin and cellulose, the team created nanofibers and nanocrystals that could be combined with water to form an ink-like substance. The ink was then used to 3D print objects, which were strengthened by freeze-drying and heating. The researchers hope that this method could eventually be used to build larger structures, such as houses, without the need for cutting down trees. [Extracted from the article]

In an unconstrained elastic body, emergence of zero natural frequencies is an expectable outcome on account of the body's ability to purely translate or rotate with no structural deformation. Recent advances in literature have pushed such conventional definition and demonstrated properties transcending typical zero-frequency modes, such as localization of deformation at a structural edge or corner. In this paper, a spring–mass honeycomb lattice with an elastic foundation, referred to here as mechanical graphene, is designed to exhibit zero-frequency corner modes. A central element in the proposed design is the elastic foundation, and the zero-frequency corner modes are enabled by intricate modulation of the elastic-foundation's stiffness. These modes are proven to have their origins from the dynamics of a diatomic chain, made from a single strip of the mechanical graphene with free boundaries. Different shapes of finite mechanical graphene with free boundaries are considered and conditions leading to the manifestation of corner modes are correlated with the angle of corners and stiffness of springs supporting them. Finally, the effect of defects on zero-frequency corner modes is briefly discussed, demonstrating robustness against structural defects that are distant from corners. • The concept of zero-frequency corner modes in a mechanical graphene is introduced. • Elastic foundation of positive-negative springs enables zero-frequency corner modes. • Corner modes origin is connected to edge modes in a comparable diatomic lattice. • Corner modes only occur in mechanical graphene having 60°-angle corners. • Theory is verified numerically using different shapes of mechanical graphene. [Display omitted] [ABSTRACT FROM AUTHOR]

Extensive studies on hexagonal honeycombs under in-plane compression have demonstrated that the structure's symmetry plays a decisive part in the emergence of deformation patterns in post-bifurcated configurations. In this work, the aim is to take advantage of this property by presenting a new group-theoretic approach to list the various attainable post-bifurcated patterns of periodic architectured materials. As of today, some group-theoretic approaches have been elaborated for determining the post-bifurcated paths and thus patterns of a symmetric system submitted to specific loading conditions. However, the application of these approaches requires knowledge of the system's governing equations. By making use of another group-theoretic tool, this work predicts the various possible post-bifurcated configurations of a periodic architectured material a priori of any non-linear computation by simply assessing the symmetry group of its undeformed configuration. This approach is applied, as an example, to the buckling of regular hexagonal honeycombs but can be easily transferred to any periodic architectured material. This work is a first step towards the elaboration of a more general process for the design of architectured materials when harnessing post-bifurcated behaviour is essential. [ABSTRACT FROM AUTHOR]

Investigation of the geometrical nonlinear action of doubly curved shell panels (DCSPs) in micro scale is the main target of this paper. The proposed microshell panels (MSPs) are assumed to be made of an auxetic honeycomb core (AHOC), leading to negative magnitudes of Poisson's ratio, covered by two nanocomposite enriched coating layers (NCECLs). To conduct the size-dependent nonlinear analysis and achieve the corresponding nonlinear equilibrium path (EQP) of the proposed MSPs, the nonlocal strain gradient theory (NLSGT) is utilized. The governing equations containing the equilibrium and compatibility nonlinear partial differential equations in terms of the deformation components are analytically solved based on the Galerkin technique for different types of simply-supported panels. The achieved results of the present solution exhibit the fact that nonlocal and material length scale parameters significantly affect the EQP of the proposed MSPs especially at their post-buckling stage during their snap-through instability. By solving several numerical examples, the effects of various parameters on the size-dependent EQP of the proposed MSPs are investigated. The results indicate that the influences of size-dependency are significantly affected by the curvature and also boundary conditions of the microshells. [ABSTRACT FROM AUTHOR]

Two patients, a 12-year-old boy and a 75-year-old woman, developed honeycomb hypertrophy while being treated with netarsudil for ocular conditions. The boy had a history of corticosteroid-induced ocular hypertension and the woman had neovascular glaucoma. Both patients experienced resolution of their symptoms after discontinuing netarsudil treatment. The article provides a concise description of the cases without making any judgments or assumptions. [Extracted from the article]

The article discusses a study on synthesizing 2D silicon carbide conducted by researchers at the University of New Mexico and Lund University, Chalmers University of Technology, and Linköping University, published in the journal "Nanomaterials" and "Physical Review Letters," respectively. Two different approaches, top-down and bottom-up synthesis methods, were employed to achieve monolayer silicon carbide, showcasing it applications in luminescent devices and micro/nano electronic circuits.