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In this paper, a Wiener filtering algorithm in the wavelet domain is proposed to filter the laser self-mixing interference (SMI) signals, which is used to improve the accuracy of displacement reconstruction. The Wiener filter is theoretically constructed and applied to filter both high-frequency coefficients and low-frequency coefficients in the wavelet domain, which are obtained by two-level discrete wavelet transformation (DWT) decomposition from unfiltered SMI signals. Two-level wavelet decomposition in wavelet threshold filtering is determined without any manual judgment. Subsequently, the inverse DWT is employed to generate the filtered SMI signals. Compared with that, using wavelet threshold denoising, the results of the simulation and experiments demonstrate that the displacement reconstruction from the filtered SMI signals exhibits better accuracy when using Wiener filtering in the wavelet domain with two levels of wavelet decomposition. Also, the fake peaks due to local oscillation caused by wavelet threshold filtering can be eliminated effectively. The proposed method employs two-level wavelet decomposition, ensuring computational efficiency and achieving an 11.3% improvement in displacement reconstruction accuracy compared to wavelet threshold filtering. The maximum error ratio of the micro-displacement reconstruction is reduced to 2.7% using the Wiener filter in the wavelet domain. [ABSTRACT FROM AUTHOR]

The construction of heterogeneous interfaces is the most effective strategy to enhance the activity of catalysts for the HER. However, facile fabrication of exceptional heterogeneous interfaces remains a formidable challenge. In this work, novel heterogeneous interfaces of Ni-doped MoS2 grown on epitaxial N-doped porous carbon cages are prepared with the modified CC as a conductive carrier. Significant phase transformation (from the 2H to the 1T phase) and lattice distortion occur at the heterogeneous interface, resulting in the formation of defects and exposure of active sites. Notably, the overpotential of the Ni-MoS2/NCR/CC-2 catalyst to achieve 10 mA cm−2 is only 136 mV with a Tafel slope of 77 mV dec−1. Moreover, the catalyst exhibits remarkable catalytic stability, with a nearly imperceptible decline in performance observed after 36 h of rigorous stability testing. [ABSTRACT FROM AUTHOR]

Preparing high‐quality 2D semiconductors represented by transition metal dichalcogenides (TMDCs) is of great importance for the next‐generation devices. However, currently available 2D TMDCs contain many atomic defects, which greatly affect their electronic and optical properties. This review starts with the formation of atomic defects and their effects on the properties of 2D TMDCs. Then, techniques for characterizing atomic defects are systematically summarized, including atomic‐resolution imaging and spectroscopy measurements. Further, recent progress on defect suppression during growth and defect repair after growth is reviewed. Finally, challenges and opportunities in this important field are discussed. [ABSTRACT FROM AUTHOR]

Background and Aim: Acute liver failure (ALF) is a fatal clinical syndrome of severe hepatic dysfunction. Chemokines promote liver diseases by recruiting and activating immune cells. We aimed to investigate the role of C–C chemokine ligand 25 (CCL25) in ALF. Methods: An ALF mouse model induced by D‐galactosamine/lipopolysaccharide was evaluated through liver hematoxylin and eosin staining and serum transaminase and cytokine measurement. CCL25 expression in serum was analyzed by ELISA and in liver by immunohistochemical staining and western blot. C–C chemokine receptor 9 (CCR9)‐expressing cells in the liver were identified by immunofluorescence staining. The effects of anti‐CCL25 on ALF were evaluated in vivo. Cytokine expression and migration of CCL25‐stimulated RAW264.7 macrophages were studied. We also investigated the role of anti‐CCL25 and BMS‐345541, an NF‐κB signaling inhibitor, in vitro. NF‐κB activation was assessed via western blot, and p65 nuclear translocation was detected using cellular immunofluorescence. Results: ALF mice showed severe histological damage and high serum levels of aminotransferase and inflammatory cytokines. Elevated CCL25 and NF‐κB activation was observed in vivo. CCR9 was expressed on macrophages in ALF mouse liver. ALF was suppressed after anti‐CCL25 treatment, with significant NF‐κB inhibition. In vitro, CCL25 induced strong migration and cytokine release in RAW264.7 macrophages, which were eliminated by anti‐CCL25 and BMS‐345541. Furthermore, the NF‐κB activation and p65 nuclear translocation induced by CCL25 were also inhibited by anti‐CCL25 and BMS‐345541. Conclusion: CCL25 contributes to ALF development by inducing macrophage‐mediated inflammation via activation of the NF‐κB signaling. [ABSTRACT FROM AUTHOR]

This paper introduces a multi‐degree of freedom bionic crocodile robot designed to tackle the challenge of cleaning pollutants and debris from the surfaces of narrow, shallow rivers. The robot mimics the "death roll" motion of crocodiles which is a technique used for object disintegration. First, the design incorporated a swinging tail mechanism using a multi‐section oscillating guide‐bar mechanism. By analyzing three‐, four‐, and five‐section tail structures, the four‐section tail was identified as the most effective structure, offering optimal strength and swing amplitude. Each section of the tail can reach maximum swing angles of 8.05°, 20.95°, 35.09°, and 43.84°, respectively, under a single motor's drive. Next, the robotic legs were designed with a double parallelogram mechanism, facilitating both crawling and retracting movements. In addition, the mouth employed a double‐rocker mechanism for efficient closure and locking, achieving an average torque of 5.69 N m with a motor torque of 3.92 N m. Moreover, the robotic body was designed with upper and lower segment structures and waterproofing function was also considered. Besides, the kinematic mechanism and mechanical properties of the bionic crocodile structure were analyzed from the perspectives of modeling and field tests. The results demonstrated an exceptional kinematic performance of the bionic crocodile robot, effectively replicating the authentic movement characteristics of a crocodile. [ABSTRACT FROM AUTHOR]

The waste electrical and electronic equipment (WEEE) recycling industry in China has been booming since the beginning of the millennium and plays a critical role in pollution control and resource efficiency. And the fast growth of the WEEE recycling industry reflects the development of China's circular economy. This paper gives an outline of China's circular economy with respect to law-making actions and promotional measures, including the implementation of clean production and the building-up of recycling and remanufacturing parks. In addition, it reviews the roadmap of China's WEEE recycling industry as an example of circular economy development. Furthermore, the current status of China's WEEE recycling industry is introduced and its social-economic impacts are discussed. Finally, trends and challenges surrounding WEEE recycling and the circular economy in China are presented. [ABSTRACT FROM AUTHOR]