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Cellular materials with ultralow density (e.g., < 5 mg cm−3) are attractive candidates for acoustic applications due to their lightweight and other unique properties. However, it has remained a challenge to fabricate such materials. Here, we synthesized a series of graphene-based cellular monoliths (GMs) with densities from 4.01 to 0.82 mg cm−3 using a facile and cost-effective freeze-casting procedure. The sound absorption behaviors of the ultralight GMs were explored, and the results demonstrate that the GMs with a density over 2.24 mg cm−3 could effectively dissipate the incident sound wave energy with the sound absorption coefficient > 0.8 in a broad frequency of ranges. Together with their high mechanical stability, fire retardancy and thermal insulation capability, GMs may find applications in the domestic, industrial and defence areas. [ABSTRACT FROM AUTHOR]

Human bodily movements are primarily controlled by the contractions of skeletal muscles. Unlike joint or skeletal movements that are generally performed in the large displacement range, the contractions of the skeletal muscles that underpin these movements are subtle in intensity yet high in frequency. This subtlety of movement makes it a formidable challenge to develop wearable and durable soft materials to electrically monitor such motions with high fidelity for the purpose of, for example, muscle/neuromuscular disease diagnosis. Here we report that an intrinsically fragile ultralow-density graphene-based cellular monolith sandwiched between silicone rubbers can exhibit a highly effective stress and strain transfer mechanism at its interface with the rubber, with a remarkable improvement in stretchability (>100%). In particular, this hybrid also exhibits a highly sensitive, broadband-frequency electrical response (up to 180 Hz) for a wide range of strains. By correlating the mechanical signal of muscle movements obtained from this hybrid material with electromyography, we demonstrate that the strain sensor based on this hybrid material may provide a new, soft and wearable mechanomyography approach for real-time monitoring of complex neuromuscular–skeletal interactions in a broad range of healthcare and human–machine interface applications. This work also provides a new architecture-enabled functional soft material platform for wearable electronics. [ABSTRACT FROM AUTHOR]

Diabetic wound healing still faces great challenges due to the excessive inflammation, easy infection, and impaired angiogenesis in wound beds. The immunoregulation of macrophages polarization toward M2 phenotype that facilitates the transition from inflammation to proliferation phase has been proved to be an effective way to improve diabetic wound healing. Herein, an M2 phenotype‐enabled anti‐inflammatory, antioxidant, and antibacterial conductive hydrogel scaffolds (GDFE) for producing rapid angiogenesis and diabetic wound repair are reported. The GDFE scaffolds are fabricated facilely through the dynamic crosslinking between polypeptide and polydopamine and graphene oxide. The GDFE scaffolds possess thermosensitivity, self‐healing behavior, injectability, broad‐spectrum antibacterial activity, antioxidant and anti‐inflammatory ability, and electronic conductivity. GDFE effectively activates the polarization of macrophages toward M2 phenotype and significantly promotes the proliferation of dermal fibroblasts, the migration, and in vitro angiogenesis of endothelial cells through paracrine mechanisms. The in vivo results from a full‐thickness diabetic wound model demonstrate that GDFE can rapidly promote the diabetic wound repair and skin regeneration, through fast anti‐inflammation and angiogenesis and M2 macrophage polarization. This study provides highly efficient strategy for treating diabetic wound repair through designing the M2 polarization‐enabled anti‐inflammatory, antioxidant, and antibacterial bioactive materials. [ABSTRACT FROM AUTHOR]

Novel biodegradable flexible implant materials require precise fabrication and novel design on top of the biocompatibility and biodegradability. By injection modeling technic, the thin and well-designed circuits can be precisely manufactured. Therefore, it emerged as an attractive method toward the research of advanced implant. In this study, a simple two-step method, natural precipitation and galvanization, was introduced to prepare a chitosan-zinc composite for conducting circuit and electrodes fabrications. The chitosan-zinc composite is biocompatible and biodegradable. The unique bond between chitosan and zinc solves the conventional unstable connection problem and secures the structural stability of our products. To optimize this processing, the effect of composition and galvanization time on viscosity and ohm resistance were investigated. The high structural stability, good shear-thinning characteristics, and fine high pass signal transferring ability were verified by viscosity test, scanning electronic microscopy (SEM) and electronic impedance spectroscopy (EIS), separately. [ABSTRACT FROM AUTHOR]

Rechargeable lithium–oxygen (Li–O2) cells have aroused great attention due to their high theoretical energy density. However, a great challenge remains for the practical applications of Li–O2 cells. One of the obstacles is the instability of the Li anode with organic electrolytes, even for relatively stable ether-based electrolytes. In this work, a quasi-solid state electrolyte, composed of a polymer, an inorganic ceramic electrolyte, Li salt and a plasticizer, was prepared. The quasi-solid state electrolyte plasticized by a hybrid of an ether and ionic liquid exhibits a stable interfacial contact with the metallic Li anode. At a limited capacity of 1000 mA h g−1, the Li–O2 cell with the quasi-solid-state electrolyte can be stably cycled for 196 cycles at 400 mA g−1. The good cycling stability of the cell can be attributed to the stable metallic Li/electrolyte interface enabled by the F-containing protective layer formed in situ from the decomposition of the ionic liquid during cycling. This work provides a new design of solid state electrolytes for long-life Li–O2 cells. [ABSTRACT FROM AUTHOR]

The experiment was conducted to determine the genetic relationship between polymorphism of lipoprotein lipase(LPL) gene and intramuscular fat content in goat. 337 goats were collected from 6 goat populations including Anhui white goats, Boer goats, Linqu dairy goats, Minshan black fur goats, Jining grey goats and Matou goats. The genetic variations in exon 1,6, and 7 of LPL gene were detected by PCR-SSCP. Genetic effect of LPL gene on intramuscular fat content was analyzed by Anhui White and Boar populations. The results exhibited as follows: one polymorphism site was found in the exon1 of LPL and five genotypes were defined. Besides that, one polymorphism site was found in exon 6 and 7 of LPL gene, respectively, andthree genotypes AA, AB and BB were defined in both of exon 6 and 7. LPL gene increased intramuscular in the order of P1 (exon 1 of LPL): BB>AB>AA, P6 (exon 6 of LPL): AA>AB>BB, and P7 (exon 7 of LPL): BB>AB>AA. These results indicated that LPL gene could be considered as a candidate gene affecting intramuscular fat content in special goat populations. [ABSTRACT FROM AUTHOR]