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Amorphous intergranular films (AIFs) have been proven in experiments to improve the damage tolerance of nanocrystalline materials. However, a quantitative study is still lacking. Molecular dynamics simulations were performed here to investigate the effect of CuNb AIFs on the fracture toughness of nanocrystalline Nb. In order to clarify the role of AIFs, a bicrystal Nb model with one straight symmetrical tilt grain boundary and a mode-I crack in one of the grains was constructed, in which the AIF effect was introduced by replacing the normal grain boundary with a CuNb AIF. Then, AIF thickness-dependent tensile deformation of the bicrystal Nb samples was simulated. The work-of-fracture, which is defined as the released strain energy due to the newly generated unit area in the crack during stretching, was employed to quantify the fracture toughness of the bicrystal systems. The results show that the fracture toughness of the AIF sample can be tripled due to the blunted crack tip and the relieved stress concentration at the crack tip as compared to the AIF-free one that exhibits a brittle crack propagation behavior. Also, the thicker the AIFs, the more pronounced this reinforcing effect. More importantly, it is found that there exists a critical AIF width of 1.7 nm, below which the crack will eventually break through the AIF, and above which the crack failed to do this. It is revealed that the enhanced fracture toughness originated from the transformation of brittle crack propagation to abundant dislocation emission from AIFs. [ABSTRACT FROM AUTHOR]

Air pollution has become an important environmental and public health problem in China; improving air quality has become one of the most important tasks of the Chinese central government in recent years. In all aspects of environmental governance, the public's pro-environmental behavior is crucial to comprehensively improve air quality. This study used data provided by the 2021 China General Social Survey (CGSS) to explore the relationship between air pollution perception, environmental knowledge, and pro-environmental behavior. The results of the study indicated that: (1) Residents' subjective perception of air pollution has a significant positive impact on residents' pro-environmental behaviors. The more serious the air pollution in the surrounding area is, the more likely residents are to adopt more pro-environmental behaviors; (2) Environmental knowledge also has a positive impact on residents' pro-environmental behaviors and individuals with higher environmental knowledge are more likely to adopt more pro-environment behaviors; and (3) Environmental knowledge plays a positive regulating role in the relationship between air pollution perception and pro-environmental behavior. Individuals with higher environmental knowledge are more willing to engage in more pro-environmental behaviors when they perceive air pollution. To promote the residents' pro-environmental behaviors, we should further strengthen the education of environmental knowledge and strengthen the disclosure of environmental information. This study provides valuable insights for China to formulate environmental governance policies, enrich the research on pro-environmental behavior to a certain extent, and provide lessons for other developing countries and high-polluting countries to find environmental governance methods. [ABSTRACT FROM AUTHOR]

Purpose: Companies allowing employees to self-report business expenses face the risk of expense fraud because some occasionally engage in dishonest behavior to receive reimbursements for their use. Drawing on the technology acceptance model, this study aims to investigate the effects of perceived usefulness, perceived ease of use and perceived security on the trust in e-reimbursement systems and the relationship with honest disclosure intention. Design/methodology/approach: A self-administered questionnaire was distributed to 254 respondents, with the partial least squares structural equation modeling used to analyze the data. Findings: The findings showed that perceived security and perceived usefulness explained trust in e-reimbursement systems, whereas perceived ease of use had no significant effect on it. Corporate governance and trust in e-reimbursement systems have a positive relationship with whistleblowing intention. At the same time, corporate governance mediates the relationship between trust in e-reimbursement systems and honest disclosure intention. Originality/value: This study sheds light on using e-reimbursement systems within organizations to prevent fraudulent reimbursements and offers recommendations to management on enhancing employees' intention to engage in honest disclosure behavior through e-reimbursement systems. [ABSTRACT FROM AUTHOR]

The ADAMTS (a disintegrin and metalloprotease with thrombospondin motifs) family metalloprotease MIG-17 plays a crucial role in the migration of gonadal distal tip cells (DTCs) in Caenorhabditis elegans. MIG-17 is secreted from the body wall muscle cells and localizes to the basement membranes (BMs) of various tissues including the gonadal BM where it regulates DTC migration through its catalytic activity. Missense mutations in the BM protein genes, let-2/collagen IV a2 and fbl-1/fibulin-1, have been identified as suppressors of the gonadal defects observed in mig-17 mutants. Genetic analyses indicate that LET-2 and FBL-1 act downstream of MIG-17 to regulate DTC migration. In addition to the control of DTC migration, MIG-17 also plays a role in healthspan, but not in lifespan. Here, we examined whether let-2 and fbl-1 alleles can suppress the age-related phenotypes of mig-17 mutants. let-2(k196) fully and fbl-1(k201) partly, but not let-2(k193) and fbl-1(k206), suppressed the senescence defects of mig-17. Interestingly, fbl-1(k206), but not fbl-1(k201) or let-2 alleles, exhibited an extended lifespan compared to the wild type when combined with mig-17. These results reveal allele specific interactions between let-2 or fbl-1 and mig-17 in age-related phenotypes, indicating that basement membrane physiology plays an important role in organismal aging. [ABSTRACT FROM AUTHOR]

Fuzzy broad learning system (FBLS) is a newly proposed fuzzy system, which introduces Takagi–Sugeno fuzzy model into broad learning system. It has shown that FBLS has better nonlinear fitting ability and faster calculation speed than the most of fuzzy neural networks proposed earlier. At the same time, compared to other fuzzy neural networks, FBLS has fewer rules and lower cost of training time. However, label errors or missing are prone to appear in large-scale dataset, which will greatly reduce the performance of FBLS. Therefore, how to use limited label information to train a powerful classifier is an important challenge. In order to address this problem, we introduce Mean-Teacher model for the fuzzy broad learning system. We use the Mean-Teacher model to rebuild the weights of the output layer of FBLS, and use the Teacher–Student model to train FBLS. The proposed model is an implementation of semi-supervised learning which integrates fuzzy logic and broad learning system in the Mean-Teacher-based knowledge distillation framework. Finally, we have proved the great performance of Mean-Teacher-based fuzzy broad learning system (MT-FBLS) through a large number of experiments. [ABSTRACT FROM AUTHOR]

Soil phosphorus (P) loss induced by erosion is an imminent threat to global food security, and as the linkage between erosion and P loss, aggregate is the unit for soil P storage. This study investigated the impacts of soil texture on aggregate‐associated P and its enrichment rate by using soils with four typical textures (silty clay, clay loam, silty clay loam, and loam) from croplands with the same field management in Danjiangkou (Hubei, China), the water source for the Middle Route of South‐to‐North Water Diversion. The initial P concentration in the range of 36.5 to 411.2 mg kg−1 was generated by laboratory incubation, and aggregate‐associated P was determined by the combination of wet sieving and molybdenum blue colorimetric method. Aggregate‐associated P was shown to be mainly concentrated in <0.05 mm aggregates (23.20–315.52 mg kg−1), accounting for 30.71%–35.28% of P concentration for a unit mass of soil. In addition, aggregate‐associated P and its enrichment rate generally decreased with the decline of clay content (333.76–63.25 mg kg−1 in 1–0.5 mm size aggregate) under the same aggregate size fraction, while they all exhibited a unimodal distribution (increasing first and then decreasing) with decreasing aggregate size. Moreover, clay content made the most contribution to the increase of aggregate‐associated P (R2 > 0.56) and its enrichment rate (R2 = 64.4%, p < 0.01), while CaCO3 showed a contrary trend (R2 > 0.56, and R2 = 49.1%, p < 0.01). Collectively, variations of aggregate‐associated P and ERi were mainly attributed to soil clay fraction‐regulated P adsorption. [ABSTRACT FROM AUTHOR]

Respiratory tract infections caused by multi-drug-resistant (MDR) bacteria have been a severe risk to human health. Colistin is often used to treat the MDR Gram-negative bacterial infections as a last-line therapy. Inhaled colistin can achieve a high concentration in the lung but none of aerosolized colistin products has been approved in the USA. Liposome has been reported as an advantageous formulation strategy for antibiotics due to its controlled release profile and biocompatibility. We have developed colistin liposomal formulations in our previous study. In the present study, the cellular uptake and transport of colistin in colistin liposomes were examined in two human lung epithelium in vitro models, Calu-3 monolayer and EpiAirway 3D tissue models. In both models, cellular uptake (p < 0.05) and cellular transport (p < 0.01) of colistin were significantly reduced by the colistin liposome compared to the colistin solution. Our findings indicate that inhaled colistin liposomes could be a promising treatment for extracellular bacterial lung infections caused by MDR Pseudomonas aeruginosa (P. aeruginosa). [ABSTRACT FROM AUTHOR]

The authors have noticed that the statement of the equal contribution of the first two authors is missing in the Author Contributions of the original article.[1] The said statement should be added in the Author Contributions as follows: "Yijing Huang and Feng Qin contributed equally to this work."By Yijing Huang; Feng Qin; Kaiqing Dai; Shaohua Chen; Jiejie Li and Jianjun LiReported by Author; Author; Author; Author; Author; Author [Extracted from the article]

This study presents a lightweight, secure audio steganography system for hiding text messages for transmission over the Internet, with the aim of addressing the current problems of high computational cost and insufficient security identified in earlier studies. We propose a two-phase functioning mechanism. Text characters are first transformed into ASCII code and stored in a vector, which is then divided into three sub-vectors. These sub-vectors are scrambled using two low-complexity operations, namely a forward-backward reading technique and an odd-even index. Two scrambling loops are performed, the first on the small sub-vectors the second on the vector as a whole. In the hiding phase, the speech signal samples are divided into 256 blocks using only 200 values per block, and low-complexity quadratic and the Hénon maps are used to hide the speech signal in a random manner. The conditional LSB is applied as a low-complexity algorithm to identify hidden bits, and a special hyperchaotic map algorithm is developed to randomly choose locations. The proposed approach provides good security for a scrambled text message, with high SNR and PSNR, small MSE and PESQ, a SSIM value of close to one (As indicated in Tables 1, 2, 3, and 4), a BER value of close to zero (as shown in table 8), NCC value near +1 (as shown in table 8), and an MOS value of near five (as described in table 6), as well as a low computational hiding cost. [ABSTRACT FROM AUTHOR]

In order to solve the problems of complex reaction conditions, high energy consumption, serious pollution and unsatisfactory effect in functional finishing of textiles, the theoretical research status of click-chemical reaction in the field of textiles was summarized. The concept, characteristics, reaction types and applications of click chemistry are introduced, which include thio-ene click chemistry, thiolisocyanate click chemical reaction and thio-maleimide click chemical reaction and their applications in functional finishing such as water repellent, flame retardant, felt shrinkage and antibacterial. It is pointed out that click chemical reaction itself will be used as "Accelerant" to further promote the development of functional finishing such as flame-retardant, antibacterial, water-repellent, oil-repellent, antistatic, photochromic and felt shrinkage. Finally, the prospect of click chemistry is given, which can provide research ideas and theoretical reference for the application of click chemistry in the field of textile functional finishing. [ABSTRACT FROM AUTHOR]

Among the various factors affecting creativity and innovation, workspace environment has not been fully considered by most organizations. The literature on innovation shows that few empirical studies have investigated the influence of workspace environment on creativity and innovation. Using Ucommune (i.e., one of the largest makerspaces and entrepreneurial ecosystems in China) as an example, this research explored to what extent workspace environments affect individual and team creativity and innovation in organizations. The main results include that physical and non‐physical environments contribute positively to employees' individual and team behaviors. In addition, individual behavior can help improve employee creativity and enhance team behavior, but the direct impact of individual behavior on innovation is insignificant. Finally, team behavior can enhance organizational innovation. The findings thus provide empirical support for the increasing importance of the impact of workspace environments – especially their physical aspects – on creativity and innovation. [ABSTRACT FROM AUTHOR]

Smith–Purcell radiation (SPR) with broadly tunable spectra has attracted attention in light emission, and this free‐electron‐driven source shows great potential in illumination fields, such as terahertz sources, ultra‐compact light sources, free‐electron lasers, etc. However, it remains difficult to control the polarization properties of SPR and realize a free‐electron chiral light source. In this work, the chiral SPR with the maximum chirality (>40%) is acquired in a periodic stacked nanosquare light‐well, and the radiation chirality is manipulated by variations of the designed electron beam excitation positions. Furthermore, this work reveals that the chiroptical effect originates in the superposition of SPRs with different phases and polarization, which are derived from adjacent sidewalls. This work may deepen the comprehension of electron‐matter interaction and facilitate the development of compact electron‐driven chirality‐tunable source‐on‐chip, highlighting potential applications in photonic integration and binary data processing. [ABSTRACT FROM AUTHOR]

This study focuses on the preparation of fine-grained WC/Co composite powder using rolling ball milling and spray drying techniques. The cemented carbide composition achieved through low-pressure sintering technology was WC-10Co-0.5 Cr 3 C 2 -1TaC-0.5Ru (wt.%). To study the effect of sintering temperature on the microstructure and mechanical properties of WC-10 wt.% cemented carbide, the microstructure and phase constituents of the material were analyzed using X-ray diffractometry and scanning electron microscopy. Additionally, the physical and mechanical properties of the material were examined. The results indicate that as the sintering temperature increased from 1390 °C to 1450 °C, the grain size of WC in the alloy increased, resulting in a slight decrease in hardness, an increase in fracture toughness, and the transverse fracture strength increasing first and then decreasing. The sintered hard alloy prepared at 1410 °C exhibited fewer pores and a uniform and fine grain size, reaching a density of 99.98%, a hardness of 91.8 HRA, a fracture strength of 3962 MPa, and a fracture toughness of 14.7 MPa ⋅ m 1 / 2 [ABSTRACT FROM AUTHOR]

In recent years, researchers have increasingly directed their attention towards modulating light fields through the unique properties of two-dimensional materials and the free designability of meta-structures. Graphene, transition metal sulfides, transition metal nitrides, and other two-dimensional materials have emerged as star materials in recent years due to their extraordinary properties that are vastly different from those of traditional three-dimensional materials. As a result, these materials hold immense potential for further exploration and research. Taking advantage of the free designability of meta-structures can be an effective means of unlocking the full potential of 2D materials. Accordingly, this review presents an overview of recent research progress in the area of light field modulation achieved by combining 2D materials with meta-structures. The review initially covers the properties of 2D materials, followed by the concepts, principles, design, and preparation of meta-structures. Then the review delves into the concrete examples of the impact and effect of the combination on light field modulation. Lastly, the review concludes with a comprehensive summary and analysis of the current challenges and potential future developments of combining 2D materials with meta-structures. [ABSTRACT FROM AUTHOR]

An exoskeleton is a kind of intelligent wearable device with bioelectronics and biomechanics. To realize its effective assistance to the human body, an exoskeleton needs to recognize the real time movement pattern of the human body in order to make corresponding movements at the right time. However, it is of great difficulty for an exoskeleton to fully identify human motion patterns, which are mainly manifested as incomplete acquisition of lower limb motion information, poor feature extraction ability, and complicated steps. Aiming at the above consideration, the motion mechanisms of human lower limbs have been analyzed in this paper, and a set of wearable bioelectronics devices are introduced based on an electromyography (EMG) sensor and inertial measurement unit (IMU), which help to obtain biological and kinematic information of the lower limb. Then, the Dual Stream convolutional neural network (CNN)-ReliefF was presented to extract features from the fusion sensors' data, which were input into four different classifiers to obtain the recognition accuracy of human motion patterns. Compared with a single sensor (EMG or IMU) and single stream CNN or manual designed feature extraction methods, the feature extraction based on Dual Stream CNN-ReliefF shows better performance in terms of visualization performance and recognition accuracy. This method was used to extract features from EMG and IMU data of six subjects and input these features into four different classifiers. The motion pattern recognition accuracy of each subject under the four classifiers is above 97%, with the highest average recognition accuracy reaching 99.12%. It can be concluded that the wearable bioelectronics device and Dual Stream CNN-ReliefF feature extraction method proposed in this paper enhanced an exoskeleton's ability to capture human movement patterns, thus providing optimal assistance to the human body at the appropriate time. Therefore, it can provide a novel approach for improving the human-machine interaction of exoskeletons. [ABSTRACT FROM AUTHOR]

The Bowden cable is a significant force transmission equipment for a flexible exoskeleton. However, the previous researches of Bowden cable had emphasized on the data from experimenting test board, instead of on human body, which produced the inaccurate assisting analysis of the flexible exoskeleton. In this paper, a flexible exoskeleton for assisting knee extension was proposed, which provided an on-body condition. Then, the friction force and its influencing factors between the wire rope and sheath of the Bowden cable from the motor to the anchor of knee have been analyzed. The segment models of force transmission with the concern of three kinds of friction modes were established, and the relationship between various lengths and bending angles of Bowden cable was fitted to the equations of curve. Furthermore, the association rule between the force transmission and the lengths of Bowden cable was obtained, based on which, the optimal force transmission efficiency was 78.68% when the length value of the Bowden cable was 475 mm. A flexible exoskeleton prototype was assembled; then, the experiments with force transmission and metabolic cost have been developed. The results showed that the force transmission efficiency had strong association with the lengths of Bowden cable, instead of the transmission velocities. Furthermore, this knee assistance exoskeleton reduced the net metabolic cost of the testees during walking. These experiments results corroborated the force transmission modeling and simulation of the Bowden cable on body we proposed in this paper. [ABSTRACT FROM AUTHOR]

Polydopamine (PDA) nanoparticles have emerged as an attractive biomimetic photothermal agent in photothermal antibacterial therapy due to their ease of synthesis, good biodegradability, long‐term safety, and excellent photostability. However, the therapeutic effects of PDA nanoparticles are generally limited by the low photothermal conversion efficiency (PCE). Herein, PDA@Ag nanoparticles are synthesized via growing Ag on the surface of PDA nanoparticles and then encapsulated into a cationic guar gum (CG) hydrogel network. The optimized CG/PDA@Ag platform exhibits a high PCE (38.2%), which is more than two times higher than that of pure PDA (16.6%). More importantly, the formulated CG/PDA@Ag hydrogel with many active groups can capture and kill bacteria through effective interactions between hydrogel and bacteria, thereby benefiting the antibacterial effect. As anticipated, the designed CG/PDA@Ag system combined the advantages of PDA@Ag nanoparticles (high PCE) and hydrogel (preventing aggregation of PDA@Ag nanoparticles and possessing inherent antibacterial ability) is demonstrated to have superior antibacterial efficacy both in vitro and in vivo. This study develops a facile approach to boost the PCE of PDA for photothermal antibacterial therapy, providing a significant step forward in advancing the application of PDA nano‐photothermal agents. [ABSTRACT FROM AUTHOR]

The widespread screen sharing poses a great challenge in the visual quality control of industrial applications, as there is a significant difference between the visual quality perception of natural content (NC) and screen content (SC) images (or videos) during acquisition, compression, distribution, and display. Apart from the foreground distortion, artifacts appeared in the smooth background of SC images also play a key role in its perceived quality. In this article, a robust approach is designed for quality measurement of SC images, which embodies both foreground perception and background suppression (FPBS) in a satisfying way. Specifically, the extraction of foreground perceptual features is investigated by considering both the local contrast variation and the local edge response features, while for the first time, a suppression strategy is devised to eliminate the influences of artifacts appeared in the simple and homogeneous background. Experimental results show that, based on only two simple features, the proposed scheme achieves the state-of-the-art results on two latest benchmark databases. We believe that the feature engineering method can further improve the performance of the FPBS framework on the quality measurement of screen images. [ABSTRACT FROM AUTHOR]

Urban pluvial flooding now occurs more frequently than it has in past decades, mainly due to an increasing number of extreme precipitation events occurring in the context of a changing climate. To limit the evolving risks of urban pluvial flooding in a more environmentally friendly manner, the research community has recently paid increasing attention to Nature‐Based Solutions (NBS), which are based on new green technologies. To meet the urgent demand for a comprehensive review of the most recent literature, this review conducts a systematic survey of the literature to characterize various NBS adopted in different regions of the world and to elaborate on the benefits and limitations of such NBS. The review highlights the role of NBS in urban flood risk management under ongoing climate change and rapid urbanization. It shows that NBS could effectively mitigate urban flooding caused by high‐frequency precipitation events, with additional economic, ecological, and social benefits. However, NBS are less effective at helping cope with pluvial flooding caused by extreme precipitation events over a short period of time, while gray infrastructures also have limitations as a mitigation measure against extreme pluvial flooding. We thus recommend identifying flood risk management strategies by evaluating the performance of alternative combinations of NBS with gray infrastructures in preventing pluvial flooding in the cities. Finally, recent advances made in the applications of NBS are presented with suggestions (e.g., long‐term monitoring) to improve urban flood adaptive management. This article is categorized under:Engineering Water > Planning WaterEngineering Water > Sustainable Engineering of WaterScience of Water > Water Extremes [ABSTRACT FROM AUTHOR]

Abstract: Conducting ferroelectric domain walls attract a wide range of research interest due to their promising applications in nanoelectronics. In this study, we reveal an unexpected enhanced conductivity near the well‐aligned 71° nonpolar domain walls in BiFeO3. Such an interfacial conductivity is induced by the creation of up‐polarized nano‐domains near the 71° domain walls, as revealed by the combination of the piezo‐response force microscopy (PFM) and conducting atomic force microscopy (c‐AFM) imaging techniques, as well as phase‐field simulations. The upward polarized domains are suggested to lower the Schottky barrier at the interface between the tip and sample surface, and then give rise to the enhanced interfacial conductivity. The result provides a new strategy to tune the local conductance in ferroelectric materials and opens up new opportunities to design novel nanoelectronic devices. [ABSTRACT FROM AUTHOR]

The front cover image is based on the Overview Nature‐based solutions for urban pluvial flood risk management, Zhan Tian et al., https://doi.org/10.1002/wat2.1421 [ABSTRACT FROM AUTHOR]