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Abstract Load bearing/energy storage integrated devices (LEIDs) allow using structural parts to store energy, and thus become a promising solution to boost the overall energy density of mobile energy storage systems, such as electric cars and drones. Herein, with a new high-strength solid electrolyte, we prepare a practical high-performance load-bearing/energy storage integrated electrochemical capacitors with excellent mechanical strength (flexural modulus: 18.1 GPa, flexural strength: 160.0 MPa) and high energy storage ability (specific capacitance: 32.4 mF cm−2, energy density: 0.13 Wh m−2, maximum power density: 1.3 W m−2). We design and compare two basic types of multilayered structures for LEID, which significantly enhance the practical bearing ability and working flexibility of the device. Besides, we also demonstrate the excellent processability of the LEID, by forming them into curved shapes, and secondarily machining and assembling them into complex structures without affecting their energy storage ability.

Abstract Methane activation by photocatalysis is one of the promising sustainable technologies for chemical synthesis. However, the current efficiency and stability of the process are moderate. Herein, a PdCu nanoalloy (~2.3 nm) was decorated on TiO2, which works for the efficient, stable, and selective photocatalytic oxidative coupling of methane at room temperature. A high methane conversion rate of 2480 μmol g−1 h−1 to C2 with an apparent quantum efficiency of ~8.4% has been achieved. More importantly, the photocatalyst exhibits the turnover frequency and turnover number of 116 h−1 and 12,642 with respect to PdCu, representing a record among all the photocatalytic processes (λ > 300 nm) operated at room temperature, together with a long stability of over 112 hours. The nanoalloy works as a hole acceptor, in which Pd softens and weakens C-H bond in methane and Cu decreases the adsorption energy of C2 products, leading to the high efficiency and long-time stability.

Abstract Optical coherence tomography (OCT) images is widely used in ophthalmic examination, but their qualities are often affected by noises. Shearlet transform has shown its effectiveness in removing image noises because of its edge-preserving property and directional sensitivity. In the paper, we propose an adaptive denoising algorithm for OCT images. The OCT noise is closer to the Poisson distribution than the Gaussian distribution, and shearlet transform assumes additive white Gaussian noise. We hence propose a square-root transform to redistribute the OCT noise. Different manufacturers and differences between imaging objects may influence the observed noise characteristics, which make predefined thresholding scheme ineffective. We propose an adaptive 3D shearlet image filter with noise-redistribution (adaptive-SIN) scheme for OCT images. The proposed adaptive-SIN is evaluated on three benchmark datasets using quantitative evaluation metrics and subjective visual inspection. Compared with other algorithms, the proposed algorithm better removes noise in OCT images and better preserves image details, significantly outperforming in terms of both quantitative evaluation and visual inspection. The proposed algorithm effectively transforms the Poisson noise to Gaussian noise so that the subsequent shearlet transform could optimally remove the noise. The proposed adaptive thresholding scheme optimally adapts to various noise conditions and hence better remove the noise. The comparison experimental results on three benchmark datasets against 8 compared algorithms demonstrate the effectiveness of the proposed approach in removing OCT noise.

Abstract The mammalian cochlea possesses unique acoustic sensitivity due to a mechanoelectrical ‘amplifier’, which requires the metabolic support of the cochlear lateral wall. Loud sound exposure sufficient to induce permanent hearing damage causes cochlear blood flow reduction, which may contribute to hearing loss. However, sensory epithelium involvement in the cochlear blood flow regulation pathway is not fully described. We hypothesize that genetic manipulation of the mechanoelectrical transducer complex will abolish sound induced cochlear blood flow regulation. We used salsa mice, a Chd23 mutant with no mechanoelectrical transduction, and deafness before p56. Using optical coherence tomography angiography, we measured the cochlear blood flow of salsa and wild-type mice in response to loud sound (120 dB SPL, 30 minutes low-pass filtered noise). An expected sound induced decrease in cochlear blood flow occurred in CBA/CaJ mice, but surprisingly the same sound protocol induced cochlear blood flow increases in salsa mice. Blood flow did not change in the contralateral ear. Disruption of the sympathetic nervous system partially abolished the observed wild-type blood flow decrease but not the salsa increase. Therefore sympathetic activation contributes to sound induced reduction of cochlear blood flow. Additionally a local, non-sensory pathway, potentially therapeutically targetable, must exist for cochlear blood flow regulation.