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Finite element simulation is one of the effective means to study the stress evolution of thermally grown oxides （TGO） at the interface of thermal barrier coatings （TBCs）， which can provide theoretical support for exploring the failure mechanism of TBCs. Advanced thermal barrier coating multifactor coupling test equipment was used to conduct thermal-mechanical coupling cycle tests and thermal cycling tests on circular tube specimens coated with TBCs， simulating engine operating conditions. Finite element modeling was conducted on TBCs containing real initial TGO morphology using finite element software ABAQUS， and the stress and deformation patterns of the coatings during tests were analyzed. The results show that without considering TGO and interface cracking， both the thermal-mechanical coupling model and the thermal cycle model exhibit an increase in Mises stress as the number of cycles increases. During the heating process， TGO is subjected to tension， while during the cooling process， TGO is compressed. The stress during the heating process is much lower than that during cooling to room temperature. After the same number of cycles， the stress values in thermal-mechanical coupling model are higher than those in the thermal cycle model. After 20， 45， 70 thermal cycles， the TGO stresses at room temperature reach 2.85， 3.65 GPa and 3.55 GPa， respectively. After the same number of thermal-mechanical coupling cycles；when cooling to room temperature，TGO stresses at the same position at room temperature reach 4.01 GPa， 5.0 GPa and 4.81 GPa， respectively. Compared with thermal cycles， under thermal coupling conditions， the TGO stress significantly increased after the same cycles when cooling to room temperature.

This study was designed to evaluate the acaricidal effect and the mode of action of lemongrass essential oil (LEO) against Aleuroglyphus ovatus. Contact and fumigant mortality indicated that LEO had higher acaricidal activities at a low concentration, and the acaricidal action of LEO was significantly more effective by contact effects than by fumigant bioassay. Repellent rate against A. ovatus at different concentrations of LEO increased with application time. Observation on the toxic symptoms revealed that almost all mites were in immobilized type (IM type) in 30 min, but the symptom of knock-down type (KD type) appeared later. Cuticles of mites killed by LEO exhibited obvious colour change and deformation. Detoxification enzyme activity assay showed that glutathione S-transferase (GST) activity increased in mites treated by LEO compared to the controls. LEO increased catalase (CAT) activity of A. ovatus but inhibited superoxide dismutase (SOD) after 20 h. LEO also increased nitric oxide synthetase (NOS) and inhibited acetylcholine esterase (AChE) activities. Moreover, LEO acted as a fast-acting neurotoxin on A. ovatus. Our results suggest that LEO has an acaricidal potential and is a promising agent in control of A. ovatus. [ABSTRACT FROM AUTHOR]

Toxoplasmosis, a parasitic disease resulting from Toxoplasma gondii infection, remains prevalent worldwide, and causes great harm to immunodepressed patients, pregnant women and newborns. Although various molecular approaches to detect T. gondii infection are available, they are either costly or technically complex. This study aimed at developing a rapid visual detection assay using recombinase-aided amplification (RAA) and lateral flow dipstick (LFD) coupled with CRISPR-Cas13a fluorescence (RAA-Cas13a-LFD) to detect T. gondii. The RAA-Cas13a-LFD assay was performed in an incubator block at 37 °C within 2 h, and the amplification results were visualized and determined through LFD by the naked eye. The detection limit was 1 × 10−6 ng/μL by our developed RAA-Cas13a-LFD protocol, 100-fold higher than that by qPCR assay (1 × 10−8 ng/μL). No cross-reaction occurred either with the DNA of human blood or Ascaris lumbricoides, Digramma interrupta, Entamoeba coli, Fasciola gigantica, Plasmodium vivax, Schistosoma japonicum, Taenia solium, and Trichinella spiralis, and the positive rate by RAA-Cas13a-LFD assay was identical to that by qPCR assay (1.50% vs. 1.50%) in detecting T. gondii infection in the unknown blood samples obtained from clinical settings. Our findings demonstrate that this RAA-Cas13a-LFD assay is not only rapid, sensitive, and specific and allows direct visualization by the naked eye, but also eliminates sophisticated and costly equipment. More importantly, this technique can be applied to on-site surveillance of T. gondii.

Rosemary (Rosmarinus officinalis L) essential oil (REO) has an inhibitory effect against pests and is regarded as a safe alternative to synthetic acaricides. This study investigated the acaricidal and repellent activity of REO and underlying mechanisms against Aleuroglyphus ovatus, an important mite pest of stored products. Gas Chromatography-Mass Spectrometry analysis of REO indicated that the compounds of 1,8-cineole (25.20%) was the highest. REO at 13% concentration provided the highest repellent effect (92.67%) on A. ovatus, and the lowest repellent activity (48.67%) was at 0.8% concentration. Microscopic observations revealed that the mite epidermis started to shrink after treatment with REO at 6 h post-treatment. The enzyme level of catalase (CAT), acetylcholinesterase (AChE) and superoxide dismutase (SOD) decreased significantly (P < 0.05), whereas there was a significant increase (P < 0.05) in nitric oxide synthase (NOS) and glutathione-s-transferases (GST) activities in A. ovatus treated with REO. In the molecular docking study, camphor and 1,8-cineole, the main monoterpenes of REO, bind more closely with CAT and AChE, and PI-conjugated interaction, hydrogen bonding, and hydrophobic were found by molecular docking 3D model. Overall, our results indicate the potential of REO as an effective botanical acaricide to manage A. ovatus. [ABSTRACT FROM AUTHOR]

Lenses are ubiquitously used for imaging. Compared with conventional lenses containing rigid translating components driven by mechanical motors, nonmechanical tunable lenses have been drawing attention owing to their advantages in compactness, lightweight, low power consumption, and fast response. Herein, inspired by the accommodation mechanism of the human eye, an all‐solid electromechanically tunable lens driven by a dielectric elastomer actuator is presented. A soft, stretchable, transparent, and ionically conductive polyelectrolyte elastomer, poly(3‐acrylamidopropyl)trimethylammonium chloride, is synthesized and used as the electrodes, one of which is plano‐convex and the other planar. A mold‐free procedure is elaborated to eliminate the contamination by molding and for facile fabrication. Subject to voltage, the resulting tunable lens achieves a relative change of focal length of ≈46.4%, superior to that of the human eye. The electro–mechano–optical coupling of the lens is modeled and the theoretical predictions agree well with the experimental results. Moreover, the tunable lens responds fast, operates stably in the ambient and desiccated environment, maintains performances over 1000 cycles, and exhibits a shelf‐life longer than 12 weeks. The polyelectrolyte elastomer‐based all‐solid tunable lens promises a potential solution for lightweight, compact, and durable imaging systems. [ABSTRACT FROM AUTHOR]