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Dielectric capacitors, which can achieve tremendous power density and ultrafast charge/discharge speed, are crucial components for high power equipment. Yet, the synchronous achievement in high recoverable energy density (Wrec) and high efficiency (η) is a long‐term difficulty for dielectric ceramics. Herein, the (0.85 − x)NaNbO3–0.15BaTiO3–xBi(Mg1/3Ta2/3)O3 (NN–BT–xBMT) relaxor ferroelectric ceramics were proposed and studied. The doping of BMT was conducive to promoting the microstructure and bandgap and improving the dielectric relaxation properties of NN–BT ceramics. Finally, the sample of x = 0.10 presented a high Wrec of 5.9 J/cm3 and a high η of 90% simultaneously. In addition, the sample also exhibited superb charge/discharge performances with large power density (PD = 137 MW/cm3) and fast charge/discharge speed (t0.9 = 39 ns). The above results reveal that the NaNbO3‐based ceramics could serve as potential alternatives for advanced dielectric capacitors. [ABSTRACT FROM AUTHOR]

The migratory and omnivorous common crane (Grus grus) uses a nature reserve with crucial ecological value that provides supplementary food resources, although the extent of their use by these cranes is unknown. In this study, we used DNA metabarcoding of plants through the chloroplast rbcL gene to investigate the diets of 25 common crane fecal samples and performed analyses in conjunction with supplementary feeding. The results showed that common cranes preferred plants of the families Poaceae and Cyperaceae, similar to common cranes in other nature reserves. Before supplementary feeding, Poaceae and Cyperaceae accounted for 43.83 ± 20.58% and 53.51 ± 19.24%, respectively, while after that, they accounted for 61.23 ± 35.19% and 24.07 ± 28.20%, respectively. The relative abundance of Hordeum increased significantly in January, accounting for 33.88 ± 31.32%, which was mainly affected by supplementary feeding. Therefore, under supplementary feeding, foraging grounds and feeding preferences of common cranes may change correspondingly. The quantity of corn kernels and wheat grains can be increased appropriately in supplementary feeding measures in the nature reserve, and more supplementary feeding sites should be set up in response to the shortage of wild bird food resources. This study applied an effective method to study the diet preference of common cranes under supplementary feeding and further provided insights to improve management measures in the nature reserve. [ABSTRACT FROM AUTHOR]

In this study, a high‐entropy perovskite oxide Sr(Zr0.2Sn0.2Hf0.2Ti0.2Nb0.2)O3 (SZSHTN) was first introduced to Na0.5Bi0.5TiO3 (NBT) lead‐free ferroelectric ceramics to boost both the high‐temperature dielectric stability and energy storage performance. Excellent comprehensive performance was simultaneously obtained in the 0.8NBT–0.2SZSHTN ceramic with high ε′ value (> 2000), wide ε′‐temperature stable range (TCC < 5%, 52.4–362°C), low tanδ value in a wide range (<0.01, 90–341°C) and high energy storage performance (Wrec = 3.52 J/cm3, Wrec and η varies ±6.08% and ±7.4% from 20 to 150°C), which endows it the promising potential to be used in high‐temperature environments. [ABSTRACT FROM AUTHOR]

Optogenetics has become a widely used technique in neuroscience research, capable of controlling neuronal activity with high spatiotemporal precision and cell‐type specificity. Expressing exogenous opsins in the selected cells can induce neuronal activation upon light irradiation, and the activation depends on the power of incident light. However, high optical power can also lead to off‐target neuronal activation or even cell damage. Limiting the incident power, but enhancing power distribution to the targeted neurons, can improve optogenetic efficiency and reduce off‐target effects. Here, the use of optical lenses made of polystyrene microspheres is demonstrated to achieve effective focusing of the incident light of relatively low power to neighboring neurons via photonic jets. The presence of microspheres significantly localizes and enhances the power density to the target neurons both in vitro and ex vivo, resulting in increased inward current and evoked action potentials. In vivo results show optogenetic stimulation with microspheres that can evoke significantly more motor behavior and neuronal activation at lowered power density. In all, a proof‐of‐concept of a strategy is demonstrated to increase the efficacy of optogenetic neuromodulation using pulses of reduced optical power. [ABSTRACT FROM AUTHOR]

The comprehensive design of uniform robust exact disturbance observer (UREDO) and fixed‐time controller for reusable launch vehicles is investigated. A UREDO which can estimate the disturbance after a fixed‐time independent of the initial error is presented. Based on the disturbance estimation, a non‐singular terminal sliding mode controller is designed to ensure that the guidance command can be tracked within a fixed‐time in the presence of model uncertainties and external disturbances. A proof of the fixed‐time convergence of the closed‐loop system under the control scheme is derived with complete stability analysis using the Lyapunov technique. The features of the proposed control scheme contain that the disturbance estimation, as well as the attitude tracking, can be achieved within a fixed‐time, which is independent of initial conditions and the derivative information of states is not essential, which is valuable in engineering application. Numerical simulations are performed to demonstrate the fixed‐time convergence performance of the proposed control scheme. [ABSTRACT FROM AUTHOR]