Recipe for Simultaneously Achieving Customizable Sound Absorption and Mechanical Properties in Lattice Structures

\ua9 2024 The Author(s). Advanced Materials Technologies published by Wiley-VCH GmbH.Lattice structures with customizable acoustical and mechanical properties show significant promise as practical engineering materials. However, the geometry of traditional lattice structures simultaneously dictates both acoustical and mechanical properties, with alterations in one impacting the other, leaving little room for customization. Herein, leveraging the mechanism of Helmholtz resonators, a general recipe is presented to independently introduce sound absorption and mechanical properties in lattice structures. The sound absorption component is based on a perforated plate, while the mechanical component is based on a truss structure. Through a high-fidelity analytical acoustics model is developed, and finite element analysis outlines the range of properties achievable through the proposed structures. The design encompasses structures with effective absorption, characterized by a resonance peak with coefficient ≥0.7, across almost every frequency in a broad range from 1000 to 5000 Hz, within a range of lattice thicknesses from 21 to 25.5 mm. Also, diverse range of stiffness and strength, and large-strain deformation modes, can be achieved through the implementation of different trusses. Finally, the concept is validated experimentally through 3D-printed samples. This innovative approach allows for the tailored creation of lattice structures that specifically address the acoustical and mechanical requirements in diverse applications

Horsetail-inspired lattice structures for bone scaffold applications

\ua9 2024 Author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution License, permitting distribution, and reproduction in any medium, provided the original work is properly cited.A well-design bone scaffold is critical for facilitating post in vivo implantation recovery. Key factors, such as elastic moduli matching to alleviate stress shielding, anisotropic characteristics, and sufficient porosity for cell ingrowth, shape the design consideration for bone scaffolds. Herein, we propose a novel body-centered cubic (BCC) lattice with modified horsetail inspired cross-section strut members as the building block for synthetic bone scaffold application. We demonstrated that geometrical parameters can be varied to attain expected desirable mechanical properties. We also successfully matched the performance of the physical compression tests of Ti-6Al-4V-based samples manufactured using selective laser melting to that of the simulation environment to facilitate design. Through our work, we created Ti-6Al-4V-based lattices, which match the mechanical performance of native bone in terms of elastic moduli and yield strength. Biologically, the lattices provide in-strut pore dimensions that facilitate bone cell ingrowth as well as yield point that is beyond the strain required to promote secondary healing. The good energy absorption capability of our lattices also adds resilience to accidental damage when applied for use in bone scaffold design. We also discovered that the isotropy characteristic is decoupled from the outer radius of the designed lattice; this avoids convolution that would otherwise increase design difficulties. Through this novel design, the tuning of the mechanical properties to attain the key considerations with geometrical variations is made possible

Genome-Wide Functional Profiling Reveals Genes Required for Tolerance to Benzene Metabolites in Yeast

Benzene is a ubiquitous environmental contaminant and is widely used in industry. Exposure to benzene causes a number of serious health problems, including blood disorders and leukemia. Benzene undergoes complex metabolism in humans, making mechanistic determination of benzene toxicity difficult. We used a functional genomics approach to identify the genes that modulate the cellular toxicity of three of the phenolic metabolites of benzene, hydroquinone (HQ), catechol (CAT) and 1,2,4-benzenetriol (BT), in the model eukaryote Saccharomyces cerevisiae. Benzene metabolites generate oxidative and cytoskeletal stress, and tolerance requires correct regulation of iron homeostasis and the vacuolar ATPase. We have identified a conserved bZIP transcription factor, Yap3p, as important for a HQ-specific response pathway, as well as two genes that encode putative NAD(P)H:quinone oxidoreductases, PST2 and YCP4. Many of the yeast genes identified have human orthologs that may modulate human benzene toxicity in a similar manner and could play a role in benzene exposure-related disease

Singapore

10.1016/B978-0-08-100853-9.00031-2539-55