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Preschool teachers’ teaching innovation is an important factor in enhancing teaching quality and improving children’s creativity. Based on ecological systems theory and self-determination theory, the purpose of this study was to investigate the relationship between kindergartens’ organizational climate and preschool teachers’ teaching innovation and the mediating role of teaching efficacy in it. In this study, an online questionnaire was distributed to 2092 preschool teachers from different provinces using an Organizational Climate Scale, Teaching Efficacy Scale, and Teaching Innovation Scale. The study used SPSS 25.0 software and the SPSS PROCESS macro program for data processing. The results showed that there was a positive correlation among kindergartens’ organizational climate, teaching efficacy, and teaching innovation, and that kindergartens’ organizational climate not only directly and positively predicted teaching innovation, but also indirectly predicted teaching innovation through the mediating role of teaching efficacy. The study explored the internal and external influences on preschool teachers’ teaching innovation and revealed their underlying mechanisms, providing theoretical support for research and educational practice on preschool teachers’ teaching innovation and children’s creativity.

Increased stiffness of tissues has been recognised as a diagnostic feature of pathologies. Tissue stiffness characterisation usually involves the detection of tissue response from mechanical stimulation. Air-puff optical coherence elastography (OCE) can generate impulse surface acoustic waves (SAWs) on tissue surface without contact and evaluate the mechanical properties of tissue. This study endeavours to explore the optimal excitation angle for air-puff OCE, a parameter that lacks standardisation at present, by investigating the relationship between the frequency bandwidth and peak-to-peak signal-to-noise ratio (SNR) of SAWs for different excitation angles (relative to the normal surface) of air-puff on the sample, from 5° to 85°, with an interval of 5° applied on the phantom. Due to the unevenness of human hands, 20°, 45° and 70° angles were employed for human skin (10 healthy adults). The results show that a smaller excitation angle could produce higher wave frequency bandwidth; a 5° angle generated an SAW with 1747 Hz frequency bandwidth, while an 85° angle produced an SAW with 1205 Hz. Significant differences were not shown in peak-to-peak SNR comparison between 5° and 65° on the phantom, but between 65° and 85° at the excitation position, a reduction of 48.6% was observed. Furthermore, the group velocity of the SAWs was used to evaluate the bulk Young’s modulus of the human tissue. The outcomes could provide essential guidance for air-puff-based elastography studies in clinical applications and future tissue research.

Candida albicans seriously threatens human health, especially for immunosuppressed groups. The antifungal agents mainly include azoles, polyenes and echinocandins. However, the few types of existing antifungal drugs and their resistance make it necessary to develop new antifungal drugs. Bacillus and its metabolites has antifungal activity against pathogenic fungi. This review introduces the application of Bacillus metabolites in the control of C. albicans in recent years. Firstly, several compounds produced by Bacillus spp. are listed. Then the isolation and identification techniques of Bacillus metabolites in recent years are described, including high-precision separation technology and omics technology for the separation of similar components of Bacillus metabolites. The mechanisms of Bacillus metabolites against C. albicans are distinguished from the inhibition of pathogenic fungi and inhibition of the fungal virulence factors. The purpose of this review is to systematically summarize the recent studies on the inhibition of pathogenic fungi by Bacillus metabolites. The review is expected to become the reference for the control of pathogenic fungi such as C. albicans and the application of Bacillus metabolites in the future.

Left-behind children seem to be more sensitive in interpersonal communication, find it more difficult to establish a stable, safe relationship with surrounding people, and have fewer positive coping styles when encountering problems, thus the aim of the present study was to explore the association between left-behind experiences and cyberbullying behavior among Chinese college students through the mediation of sense of security and the moderation of gender. A questionnaire survey comprised 553 college students with left-behind experiences and 526 college students without such experiences. The results showed that, firstly, cyberbullying behavior was significantly higher in college students with left-behind experiences than those without such experiences; secondly, left-behind experiences and cyberbullying behavior in college students was partially mediated by a sense of security; and finally, that gender moderated the mediation of the sense of security between left-behind experiences and cyberbullying behavior. This study suggests the family environment is important for individual growth and illustrates how the influence of childhood left-behind experience persists in individuals.

In the realm of civil engineering, ultra-high-performance concrete-filled steel tube composite columns (UCFSTCs) constitute a new type of building material and structure, exhibiting high compressive strength and commendable durability. Given their promising characteristics, the prospects of their application are highly promising and are worthy of further exploration. However, current research has primarily focused on scaled-down specimens, thereby limiting a broader understanding of UCFSTCs’ full-scale mechanical properties in real-world scenarios. This study aimed to investigate the mechanical properties of full-scale UHPC-filled steel tube composite columns (FUCFSTCs) in practical engineering applications. With the steel tube strength, steel tube thickness, concrete strength, aspect ratio, and steel tube diameter used as design parameters and the finite element software ABAQUS as the analytical tool, a total of 21 FUCFSTCs were designed and analyzed. Through a comparison with experimental curves, the rationality of both the material constitutive model and finite element model was verified, and the maximum error was 6.54%. Furthermore, this study analyzed the influence of different design parameters on FUCFSTCs’ ultimate bearing capacity, ductility coefficient, and the stress–strain relationship of their concrete. The ductility coefficient remained around 1.3, and the cross-sectional size had the greatest impact on the bearing capacity of the composite column, with a maximum increase of 145.90%. Additionally, this paper provides an in-depth analysis of FUCFSTCs’ mechanical behavior, failure mode, and stress process under an axial load. In conclusion, this research proposes an axial compression limit bearing capacity formula for FUCFSTCs via statistical regression, with a maximum error of 3.04%, meeting engineering accuracy requirements. Consequently, this study lays a strong foundation for the future application of FUCFSTCs in practical engineering.

For human–machine collaborative driving conditions, a hierarchical chassis multi-objective cooperative control method is proposed in this paper. Firstly, based on the phase plane theory, vehicle dynamics analysis is carried out to complete the definition of vehicle stability region. Secondly, based on the linear time-varying (LTV) system model, a cooperative control strategy combining fuzzy control with model predictive control (MPC) is proposed in the upper layer. In this strategy, the assisted driving weight adjustment coefficient and the stability weight adjustment coefficient are obtained by fuzzy mapping combining human–machine cooperation index and the vehicle stability region, respectively, and the optimization objectives of MPC are designed based on the above coefficients. In the lower layer torque allocation strategy, the stability weight adjustment coefficient is introduced to achieve multi-objective optimization of tire load rate and energy efficiency. For energy efficiency optimization, an optimal energy efficiency point-based tracking method is proposed to avoid nonlinearity caused by the introduction of motor loss models. Simulation analysis results show that the proposed strategy can effectively alleviate human–machine conflicts and improve vehicle handing stability. It also can achieve smaller tire load rate optimization through torque allocation and can reduce energy consumption by approximately 8% compared with the inter-axle torque allocation strategy. This study helps to promote the improvement of the comprehensive performance of assisted driving vehicles in human–machine cooperation, handling stability, and energy-saving torque distribution.

In order to investigate the bearing capacity of composite columns composed of ultra-high performance concrete, (UHPC)-filled high-strength elliptical steel tube with encased high-strength H-shape steel (HUCFESTCs) were subjected to eccentric load. Forty-four HUCFESTCs were designed with varying parameters: yield strength of the steel tube (fy), yield strength of the H-shape steel (fy1), concrete-cube compressive strength (fcu), steel tube thickness (t), eccentricity (e), slenderness ratio (λ), the section area of the H-shape steel (AHS), and long–short axis ratio (ψ). Based on a bilinear elastic–plastic constitutive model of steel that considered stress hardening and a nonlinear constitutive model of UHPC, 44 HUCFESTCs models were established by ABAQUS software. The influence of different parameters on the ultimate bearing capacity of the HUCFESTCs was analyzed. The whole process of HUCFESTCs under eccentric load was studied, and the typical failure modes of HUCFESTCs are described. The results show that the main failure mode of the HUCFESTCs subjected to eccentrical load is bulging outward of the steel tube, the buckling of the H-shape steel, and crushing of the concrete in the middle part of the column and the inner part of the H-shape steel. The stiffness of HUCFESTCs increases gradually with the increase in fy, t, and e. The ultimate eccentrical compression bearing capacity of HUCFESTCs improves gradually with increases in fy, t, fy1, AHS, ψ, and fcu, but it decreases gradually with increases in λ and e. By using statistical regression and introducing the reduction coefficient of eccentricity, the calculation formula for the eccentric bearing capacity of HUCFEST columns is developed, which can provide a basis for the application of HUCFESTCs in practical engineering.

This study aims to introduce and discuss the recent research, development and application of wave energy marine buoys. The topic becomes increasingly appealing after the observation that wave energy technologies have been evolving in the recent decades, yet have not reached convergence. The power supply is usually the bottleneck for marine distributed systems such as buoys. Wave energy technologies are especially useful in this sense, as they can capture and convert the promising “native” renewable energy in the ocean (i.e., wave energy) into electricity. The paper enumerates the recent developments in wave energy capture (e.g., oscillating bodies) and power take-off (e.g., nanogenerators). The study also introduces the typical marine buoys and discusses the applicability of wave energy technologies on them. It is concluded that the wave energy technologies could be implemented as a critical addition to the comprehensive power solution of marine distributed systems. Wave energy buoys are likely to differentiate into “wave energy converter buoys” and “wave-energy-powered buoys”, which is indicated by the ratio of the generated power to the load power.

Marine distributed devices are essential infrastructure for exploring and utilizing the ocean. As the most common carrier of these devices, floating and submerged buoys are subject to a bottleneck of power supply. Recent progress in nanogenerators could convert the high-entropy marine kinetic energy (e.g., wave) robustly, which may form an in-situ power solution to marine distributed devices. This study is devoted to develop a stackable triboelectric nanogenerator (S-TENG), while each layer of it is made into multiple channels carrying PTFE balls in between Aluminum electrodes. In the experiments based on forced motion, the peak power density of the S-TENG reaches 49 W/m3, about 29% promotion from our previous benchmark. The S-TENG has also become less vulnerable to directional variation of the excitation, making its integration on various platforms more flexible in real conditions. In practice, the S-TENG has demonstrated its capability of powering LEDs as well as various sensors measuring salinity, temperature and acidity, which means the S-TENG could self-power many compact marine buoys.

Compared with the one immobilized in the conventional mesoporous microspheres, the enzyme immobilized in gigaporous microspheres showed much higher activity and better stability. To gain a deeper understanding, we herein selected lipase as a prototype to comparatively analyze the adsorption behavior of lipase at interfaces in gigaporous and mesoporous polystyrene microspheres at very low lipase concentration, and further compared with the adsorption on a completely flat surface (a chip). Owing to the limited space of narrow pores, lipase molecules were inclined to be adsorbed as a monolayer in mesoporous microspheres. During this process, the interaction between lipase molecules and the interface was stronger, which could result in the structural change of lipase molecular and compromised specific activity. In addition to monolayer adsorption, more multilayer adsorption of enzyme molecules also occurred in gigaporous microspheres. Besides the adsorption state, the pore curvature also affected the lipase adsorption. Due to the multilayer adsorption, the excellent mass transfer properties for the substrate and the product in the large pores, and the small pore curvature, lipase immobilized in gigaporous microspheres showed better behaviors.