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• Broadband waterborne absorptive metamaterial with hydrostatic pressure resistance is proposed. • Acousto-electric analogy is adopted to determine the equivalent parameters for transfer matrix method. • Oscillators of helical configurations demonstrate strong hydrostatic pressure resistance. • Experimental results confirm the superior performance of the configurations at 3 MPa. Underwater absorptive metamaterials are rapidly developed duo local resonance mechanisms, but they still suffer from the disadvantages of poor hydrostatic resistance. The poor acoustic absorption performance at high hydrostatic pressure mainly attributes to the decreased damping coefficient and increased modulus of substrate at high hydrostatic pressure. Acoustic metastructures with helical oscillators are proposed and optimized with simulating annealing algorithm, where the helical oscillators are beneficial for easing the stress in the polymer substrate and resulting in good acoustic absorption abilities. Four acoustic absorptive metastructures without any oscillators (pure polymer substrate), with cylindrical oscillators, with helical oscillators, with both cylindrical and helical oscillators are proposed and experimentally verified in this study. All three metastructures with oscillators demonstrate excellent acoustic absorption coefficient with the absence of the hydrostatic pressure, while the metastructures with helical oscillators exhibit better hydrostatic pressure resistance compared with the metastructures with cylindrical oscillators. Besides, the coupling of helical oscillators and helical oscillators enhanced the acoustic performance furtherly. It is revealed that the acoustic metamaterials with a combination of cylindrical oscillator and helical oscillator exhibit superior performance under hydrostatic pressure up to 3 MPa in the frequency range of 0.5kHz∼10 kHz compared with the others, demonstrating a new avenue for underwater acoustic metamaterials application. [Display omitted] [ABSTRACT FROM AUTHOR]

Depression is a common mental illness characterised by abnormal and depressed emotions. Total paeony glycoside (TPG) is a naturally active saponin extracted from the traditional Chinese medicine Radix Paeoniae rubra. However, the antidepressant and neuroinflammatory effects of TPG have not been thoroughly studied. To study the therapeutic potential of TGP in depression caused by neuronal injury and neuroinflammation and to explore the mechanism of TGP and the relationship between the NLRP3 inflammasome, pyroptosis, and autophagy. A chronic unpredictable mild stress (CUMS)-induced depression model and a cell model of corticosterone (CORT)-induced hippocampal neuron injury were established to evaluate the therapeutic effects of TPG. The composition of TPG was analysed using high-performance liquid chromatography and mass spectrometry. The effects of TPG and fluoxetine on depression-like behaviour, neuronal injury, neuroinflammation, pyroptosis, and mitochondrial autophagy in the mice models were evaluated. TGP alleviated depression-like behaviours in mice and inhibited hippocampal neuronal apoptosis. The secretion of inflammatory cytokines was significantly reduced in CORT-induced hippocampal neuron cells and in the serum of a mouse model of CUMS-induced depression. In addition, TGP treatment reduced the levels of NLRP3 family pyrin structural domains, including NLRP3, pro-caspase-1, caspase-1, and IL-1β, and the pyroptosis related proteins such as GSDMD-N. Importantly, TPG attenuated mitochondrial dysfunction, promoted the clearance of damaged mitochondria, and the activation of mitochondrial autophagy, which reduced ROS accumulation and NLRP3 inflammasome activation. An in-depth study observed that the regulatory effect of TPG on autophagy was attenuated by the autophagy inhibitor 3-methyladenine (3-MA) in vitro and in vivo. However, administration of the caspase-1 inhibitor Belnacasan (VX-765) successfully inhibited pyroptosis and showed a synergistic therapeutic effect with TPG. These results indicate that TPG can repair neuronal damage by activating autophagy, restoring mitochondrial function, and reducing inflammation-mediated pyroptosis, thereby playing an important role in the alleviation of neuroinflammation and depression. This study suggests new potential drugs and treatment strategies for neuroinflammation-related diseases and depression. [Display omitted] [ABSTRACT FROM AUTHOR]

• A new safety lane change trajectory model for autonomous vehicles. • Minimum safety distances in different steering frequency domain. • Vehicle collision avoidance control strategies are proposed. • Typical lane change scenarios for intelligent vehicles are designed. Lane change maneuvers, are important contributors to road traffic accidents on highway. In this paper, we propose a new safe lane change trajectory model and collision avoidance control method for Society of Automotive Engineers (SAE)-level 2 automatic driving vehicles. First, a Gaussian distribution is used to describe the new trajectory model that uses pure steering and combined braking. According to regional and progressive states, a new safe lane change meaning is defined. Second, we design a new four-level automatic driving mode and an effective decision mechanism that considers safety and ergonomics. Moreover, a new trajectory tracking controller combined with a decision mechanism was designed using feedback linearization, verified using typical lane-change scenarios. Finally, based on a physical simulation platform, PreScan, the hardware-in-the-loop simulation result demonstrate the feasibility and effectiveness of our method. This paper provides a valuable reference on an expert and intelligent system methodology for automatic driving vehicles, which will be helpful for improving highway traffic safety and efficiency. [ABSTRACT FROM AUTHOR]

In this study, Al 2 O 3 –TiC composites synergistically reinforced with multi-walled carbon nanotubes (MWCNTs) and graphene nanoplates (GNPs) were prepared via spark plasma sintering (SPS). The effects of the MWCNT and GNP contents on the phase composition, mechanical properties, fracture mode, and toughening mechanism of the composites were systematically investigated. The experimental results indicated that the composite grains became more refined with the addition of MWCNTs and GNPs. The nanocomposites presented high compactness and excellent mechanical properties. The composite with 0.8 wt% MWCNTs and 0.2 wt% GNPs presented the best properties of all analysed specimens, and its relative density, hardness, and fracture toughness were 97.3%, 18.38 ± 0.6 GPa, and 9.40 ± 1.6 MPa m1/2, respectively. The crack deflection, bridging, branching, and drawing effects of MWCNTs and GNPs were the main toughening mechanisms of Al 2 O 3 –TiC composites synergistically reinforced with MWCNTs and GNPs. [ABSTRACT FROM AUTHOR]

Indoor simulation experiment with 2.76 L microcosms using sediment from Taihu Lake were conducted to investigate the relationship between algae bloom and heavy metals release into a lake aquatic environment. The results showed that Microcystic aeruginosa (M. aeruginosa) growth can enhance cadmium (Cd) mobilization from sediments to overlying water due to increasing pH and DO content of overlying water and changing the redox condition of surface sediment (0–2 cm) from weak oxidation to weak reduction. The dissolved Cd concentration in overlying water can be decreased during algal growth process. The remobilization of Cd from sediment can effectively reduce the ecological risk of total Cd in sediments. The results of this study showed that both I geo and E r i can be used to effectively evaluate the ecological risk of heavy metal Cd in different fractions. [ABSTRACT FROM AUTHOR]

The gene therapy attracted more and more attention for the tumor therapy. To obtain a safe gene therapy system, the new gene vectors beyond the virus were developed for a high gene therapy efficiency. The ultrasound mediated gene therapy was safer and the plasmid DNA could be delivered by the microbubbles and combined with the ultrasound to increase the gene transfection efficiency. In this work, the cationic microbubbles decorated with Cyclo(Cys-Arg-Gly-Asp-Lys-Gly-Pro-AspCys) (iRGD peptides) and magnetic Fe 3 O 4 nanoparticles (MB iM) was designed for targeted ultrasound contrast imaging guided gene therapy of tumors. The ultrasound image intensity was dramatically enhanced at the tumor site that received MB iM with the magnet applied, compared to those administrated the non-targeted microbubbles (MB b) or the microbubbles with only one target material on the surface (MB M and MB bi). The pGPU6/GFP/Neo-shAKT2 was used as a sample gene, which down regulate the AKT2 protein expression for the cancer therapy. It illustrated that MB iM /AKT2 had the highest gene transfection efficiency in the studied microbubbles mediated by the ultrasound, leading to the AKT2 protein expression downregulation and the strongest tumor killing effect in vitro and in vivo. In summary, a novel and biocompatible gene delivery platform via MB iM with both the endogenous and external targeting effects for breast cancer theranostics was developed. [Display omitted] • iRGD dual-targeted magnetic microbubbles (MB iM) designed for targeted gene delivery. • The ultrasound image intensity at the tumor site was enhanced by MB iM. • The gene therapy efficiency was improved by MB iM mediated by ultrasound. [ABSTRACT FROM AUTHOR]

Abstract: Ethylene propylene diene monomer rubber composites reinforced with micro- and nano-sized short fibers were made by mechanically blending of silanized fibrillar silicate (FS) nanofibers and polyamide 66 (PA-66) microfibers. A synergistic reinforcement on static and dynamic mechanical properties was revealed. When FS nanofibers and PA-66 microfibers were used together in an appropriate volume ratio, static and dynamic mechanical properties (such as tensile stress, mechanical anisotropy, compression modulus, dynamic storage modulus and tensile fatigue property) of the resulting composites were substantially improved. The co-reinforcement mechanism of nano- and micro-sized fibers was discussed in terms of composite fracture morphology. The synergetic reinforcement effect on the dynamic fatigue properties is attributed to the result of competitive factors including stress transfer, crack initiation and propagation, and matrix reinforcement, whereas the synergetic reinforcement effect on the static tensile properties is achieved due to the strong interfacial adhesion between FS nanofibers and rubber. [Copyright &y& Elsevier]