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  1. A novel amphibious strain sensor with a periodic cut pattern and a unique interface design offers an unprecedented combination of high gauge factor, linear sensing response, and excellent stability in water/saline solution.

     
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    Free, publicly-accessible full text available October 14, 2025
  2. Functional electrical stimulation (FES) is a vital method in neurorehabilitation used to reanimate paralyzed muscles, enhance the size and strength of atrophied muscles, and reduce spasticity. FES often leads to increased muscle fatigue, necessitating careful monitoring of the patient’s response. Ultrasound (US) imaging has been utilized to provide valuable insights into FES-induced fatigue by assessing changes in muscle thickness, stiffness, and strain. Current commercial FES electrodes lack sufficient US transparency, hindering the observation of muscle activity beneath the skin where the electrodes are placed. US-compatible electrodes are essential for accurate imaging and optimal FES performance, especially given the spatial constraints of conventional US probes and the need to monitor muscle areas directly beneath the electrodes. This study introduces specially designed body-conforming US-compatible FES (US-FES) electrodes constructed with a silver nanowire/polydimethylsiloxane (AgNW/PDMS) composite. We compared the performance of our body-conforming US-FES electrode with a commercial hydrogel electrode. The findings revealed that our US-FES electrode exhibited comparable conductivity and performance to the commercial one. Furthermore, US compatibility was investigated through phantom and in vivo tests, showing significant compatibility even during FES, unlike the commercial electrode. The results indicated that US-FES electrodes hold significant promise for the real-time monitoring of muscle activity during FES in clinical rehabilitative applications.

     
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    Free, publicly-accessible full text available August 1, 2025
  3. Soft robots often draw inspiration from nature to navigate different environments. Although the inching motion and crawling motion of caterpillars have been widely studied in the design of soft robots, the steering motion with local bending control remains challenging. To address this challenge, we explore modular origami units which constitute building blocks for mimicking the segmented caterpillar body. Based on this concept, we report a modular soft Kresling origami crawling robot enabled by electrothermal actuation. A compact and lightweight Kresling structure is designed, fabricated, and characterized with integrated thermal bimorph actuators consisting of liquid crystal elastomer and polyimide layers. With the modular design and reprogrammable actuation, a multiunit caterpillar-inspired soft robot composed of both active units and passive units is developed for bidirectional locomotion and steering locomotion with precise curvature control. We demonstrate the modular design of the Kresling origami robot with an active robotic module picking up cargo and assembling with another robotic module to achieve a steering function. The concept of modular soft robots can provide insight into future soft robots that can grow, repair, and enhance functionality.

     
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    Free, publicly-accessible full text available May 14, 2025
  4. Abstract

    Direct disposal of used soft electronics into the environment can cause severe pollution to the ecosystem due to the inability of most inorganic materials and synthetic polymers to biodegrade. Additionally, the loss of the noble metals that are commonly used in soft electronics leads to a waste of scarce resources. Thus, there is an urgent need to develop “green” and sustainable soft electronics based on eco‐friendly manufacturing that may be recycled or biodegraded after the devices’ end of life. Here an approach to fabricating sustainable soft electronics is demonstrated where the expensive functional materials can be recycled and the soft substrate can be biodegradable. A stretchable agarose/glycerol gel film is used as the substrate, and silver nanowires (AgNWs) are printed on the film to fabricate the soft electronic circuits. The mechanical and chemical properties of the agarose/glycerol gel films are characterized, and the functionality of the printed AgNW electrodes for electrophysiological sensors is demonstrated. The demonstration of the biodegradability of the agarose/glycerol and the recyclability of AgNWs points toward ways to develop sustainable and eco‐friendly soft electronics.

     
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    Free, publicly-accessible full text available June 1, 2025
  5. Free, publicly-accessible full text available March 20, 2025
  6. Abstract

    Cobamides, a class of essential coenzymes synthesized only by a subset of prokaryotes, are model nutrients in microbial interaction studies and play significant roles in global ecosystems. Yet, their spatial patterns and functional roles remain poorly understood. Herein, we present an in-depth examination of cobamide-producing microorganisms, drawn from a comprehensive analysis of 2862 marine and 2979 soil metagenomic samples. A total of 1934 nonredundant metagenome-assembled genomes (MAGs) potentially capable of producing cobamides de novo were identified. The cobamide-producing MAGs are taxonomically diverse but habitat specific. They constituted only a fraction of all the recovered MAGs, with the majority of MAGs being potential cobamide users. By mapping the distribution of cobamide producers in marine and soil environments, distinct latitudinal gradients were observed: the marine environment showed peak abundance at the equator, whereas soil environments peaked at mid-latitudes. Importantly, significant and positive links between the abundance of cobamide producers and the diversity and functions of microbial communities were observed, as well as their promotional roles in essential biogeochemical cycles. These associations were more pronounced in marine samples than in soil samples, which suggests a heightened propensity for microorganisms to engage in cobamide sharing in fluid environments relative to the more spatially restricted soil environment. These findings shed light on the global patterns and potential ecological roles of cobamide-producing microorganisms in marine and soil ecosystems, enhancing our understanding of large-scale microbial interactions.

     
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  7. A framework integrating life cycle assessment, Green Chemistry, and techno-economic analysis to identify cost-effective, greener pathways for nanomaterial production, demonstrated with cellulose nanomaterials.

     
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    Free, publicly-accessible full text available March 18, 2025
  8. Abstract

    This study describes the production of biodegradable and recyclable flexible electronic devices created by screen‐printing silver nanowires (AgNWs) onto regenerated cellulose films (RCFs). RCFs, derived from microcrystalline cellulose (MCC), are developed and further enhanced for flexibility with additives such as glycerol and poly(ethylene glycol) diglycidyl ether (PEGDE). The resulting cellulose films display relatively high tensile strength (up to 120 MPa), low Young's Modulus (down to 1500 MPa), and 90% optical transparency. Ink with AgNWs and poly(ethylene oxide) (PEO) as a binder is screen‐printed on regenerated cellulose films. The printed AgNWs patterns exhibit high electrical conductivity, excellent electromechanical performance, and strong interfacial adhesion with RCFs. To demonstrate the application of printed AgNWs on RCFs for soft electronics, transparent conductive electrodes (TCEs) are fabricated. Grid and honeycomb structures are printed separately and evaluated in terms of sheet resistance and optical transparency. TCEs with ≈80% transparency and very low sheet resistance (0.045 Ω sq−1) are obtained. Furthermore, enzymatic hydrolysis of the cellulose substrate and the recovery for reuse of the AgNWs are demonstrated, showing the potential of integrating natural polymers and recyclable nanomaterials for eco‐friendly and sustainable soft flexible electronics.

     
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