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Triboelectric nanogenerators (TENGs) are a novel technology for harvesting environmental micro/nanoenergy to produce electricity. The electric field generated by different electrode properties of materials plays a crucial role in regulating the dynamic behavior of triboelectric charges between the dielectric layer and the metallic electrode. In this work, a model of dual-electric field mutual inductance TENG (DEF-TENG) is proposed, which aims to systematically study the effect of electric field mutual inductance of bilateral motors on the amount of charge in the TENG. The changed state of the dynamic electric field is obtained through theoretical analysis. By introducing an external charge from the metal, the model strengthens the effect of bilateral electric field mutual inductance, thereby improving the ability of the metal electrode surface to carry the charge and establishing a new dynamic equilibrium of triboelectric charge. The relationship between the structural parameters and the electric field mutual inductance is analyzed by deriving the theoretical formula of the DEF-TENG. The experimental results show that the open-circuit voltage and the transferred charge of the DEF-TENG are 156% and 154% higher than those of a single-electric field TENG (SEF-TENG) after introducing external charges. This study provides a novel method and guidance for linear-to-rotary triboelectric nanogenerators to improve power generation. [ABSTRACT FROM AUTHOR]

Background: Sleep disorders are a significant health issue that urgently needs to be addressed among undergraduate students, and one of the potential underlying problems could be problematic smartphone use (PSU). This study aimed to clarify the relationship between PSU and poor sleep quality by investigating the independent and serial mediating roles of anxiety and depressive symptoms in a population of university students in Tibet, China. Methods: A total of 2993 Tibetan college students completed three waves of data surveys, with all participants completing questionnaires on PSU, anxiety, depressive symptoms, and sleep quality (Time 1 (T1) -Time 3 (T3)). Bootstrapped mediation analysis was used to explore the mediating role of anxiety and depressive symptoms in the longitudinal relationship between PSU and sleep quality. Results: Both direct and indirect effects of PSU on poor sleep quality were found. PSU (T1) can had not only a direct negative influence on poor sleep quality (T3) among young adults (direct effect = 0.021, 95% CI = 0.010– 0.033) but also an indirect negative impact via three pathways: the independent mediating effect of anxiety symptoms (T2) (indirect effect 1 = 0.003, 95% CI = 0.001– 0.006), the independent mediating effect of depressive symptoms (T2) (indirect effect 2 = 0.004, 95% CI = 0.002– 0.006), and the serial mediating effects of anxiety (T2) and depressive symptoms (T2) (indirect effect 3 = 0.008, 95% CI=0.005– 0.011). Conclusion: These findings highlight the role of anxiety and depression symptoms as joint mediating factors in the relationship between PSU and sleep disturbances. Interventions focused on improving sleep that incorporate behavioural measures could benefit from treatment approaches targeting mental disorders. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) can effectively collect low-frequency, disordered mechanical energy and are therefore widely studied in the field of ocean energy collection. Most of the rotary TENGs studied so far tend to have insufficient rotation, resulting in slow charge transfer rates in low-frequency ocean environments. For this reason, in this paper, we propose a wind-wave synergistic triboelectric nanogenerator (WWS-TENG). It is different from the traditional rotary TENGs based on free-standing mode in that its power generation unit has two types of rotors, and the two rotors rotate in opposite directions under the action of wind energy and wave energy, respectively. This type of exercise can more effectively collect energy. The WWS-TENG has demonstrated excellent performance in sea wind and wave energy harvesting. In the simulated ocean environment, the peak power can reach 13.5 mW under simulated wind-wave superposition excitation; the output of the WWS-TENG increased by 49% compared to single-wave power generation. The WWS-TENG proposal provides a novel means of developing marine renewable energy, and it also demonstrates broad application potential in the field of the self-powered marine Internet of Things (IoT). [ABSTRACT FROM AUTHOR]

Recent studies have indicated that functional abnormalities in the KNa1.2 channel are linked to epileptic encephalopathies. However, the role of KNa1.2 channel in traumatic brain injury (TBI) remains limited. We collected brain tissue from the TBI mice and patients with post-traumatic epilepsy (PTE) to determine changes in KNa1.2 channel following TBI. We also investigated whether the MAPK pathway, which was activated by the released cytokines after injury, regulated KNa1.2 channel in in vitro. Finally, to elucidate the physiological significance of KNa1.2 channel in neuronal excitability, we utilized the null mutant-Kcnt2−/− mice and compared their behavior patterns, seizure susceptibility, and neuronal firing properties to wild type (WT) mice. TBI was induced in both Kcnt2−/− and WT mice to investigate any differences between the two groups under pathological condition. Our findings revealed that the expression of KNa1.2 channel was notably increased only during the acute phase following TBI, while no significant elevation was observed during the late phase. Furthermore, we identified the released cytokines and activated MAPK pathway in the neurons after TBI and confirmed that KNa1.2 channel was enhanced by the MAPK pathway via stimulation of TNF-α. Subsequently, compared to WT mice, neurons from Kcnt2−/− mice showed increased neuronal excitability and Kcnt2−/− mice displayed motor deficits and enhanced seizure susceptibility, which suggested that KNa1.2 channel may be neuroprotective. Therefore, this study suggests that enhanced KNa1.2 channel, facilitated by the inflammatory response, may exert a protective role in an acute phase of the TBI model. [ABSTRACT FROM AUTHOR]

Abstract The relationship between T-2 toxin and deoxynivalenol (DON) and the risk of Kashin-Beck disease is still controversial since it is poorly known about their selectivity in cartilage damage. We aimed to compare the cytotoxicity of T-2 toxin and DON on cell lines representative of cell types encountered in vivo, including human chondrocytes (C28/I2), human hepatic epithelial cells (L-02) and human tubular epithelial cells (HK-2). In addition, we determined the distribution of T-2 toxin and DON in Sprague-Dawley (SD) rats after a single dose exposure. T-2 toxin or DON decreased proliferation in a time- and concentration-dependent manner and their combination showed a similar antagonistic effect in C28/I2, L-02 and HK-2 cells. Moreover, we observed cell cycle arrest and apoptosis, associated with increased oxidative stress and decline in mitochondrial membrane potential induced by T-2 toxin and/or DON. In vivo study showed that T-2 toxin and DON did not accumulate preferentially in the knee joint compared to liver and kidney after an acute exposure in SD rats. These results suggest that T-2 toxin and/or DON inhibit proliferation and induce apoptosis through a possible mechanism involving reactive oxygen species-mediated mitochondrial pathway that is not specific for chondrocytes in vitro or joint tissues in vivo.

Fluid energy is one of the most common, widely distributed, and significant renewable energy sources globally, which generally exists in gases and liquids such as wind energy, airflow energy, droplet energy, water flow energy, and wave energy. Since Wang's research group first invented the triboelectric nanogenerators (TENGs) in 2012, it has been widely utilized and developed rapidly as a new energy conversion method and as a promising sensing technology. Especially in fluid sensing, the TENGs get a lot of attention. This paper comprehensively reviews the latest research on triboelectric fluid sensors (TFSs). First, the fundamental theories and basic operation modes of TFSs are briefly introduced. Then, the research status of TFSs in different functions, structural design, and output performance is summarized according to the form of fluid energy (gas‐based, liquid‐based, and multi‐phase flow‐based). In addition, the application of TFSs in different fields is also discussed in this paper. Finally, this research presents its views on the challenges and future development trends of TFSs. [ABSTRACT FROM AUTHOR]

Combined PBL with some advanced foreign reading teaching strategies, we choose the most suitable way to give lessons and bring up students ability to think of questions. Based on teaching experience for several years, we propose some teaching strategies in English reading teaching to help students improve the efficiency and accuracy of reading with the help of PBL. After practice, students’ innovation and cooperation are strengthened and the width and depth of their questions are improved.