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The micro-discharge effect limits the development of high-frequency microwave power components to miniaturization and integration. Therefore, it has become a focus of research to effectively suppress the micro-discharge effect, increase the micro-discharge threshold, and strengthen the environmental stability of high-frequency microwave devices. In this study, different elemental ratios of carbon (C)/silver (Ag)/titanium (Ti) composite films were obtained by multi-target magnetron co-sputtering technology and then systematically analyzed for micro-discharge effects. When the doping ratio of C/Ag/Ti was 3.538/1/0.013, the corresponding maximum secondary electron emission coefficient (δmax) decreased to 1.01 owing to the suppression of secondary electron emission by the increase in the content of sp2 hybrid bond. The micro-discharge threshold of Ku band waveguide filters coated with moderate C/Ag/Ti composite films showed an optimal performance of 10 000−12 500 W, which was increased by approximately 20 times. Moreover, the microstructure of the composite films exhibited higher density and flatness with a tiny increase in the titanium doping ratio, representing good environmental stability. Thus, the effective suppression of the secondary electron emission yield, significant improvement in the micro-discharge threshold, and enhancement of the environment stability of microwave components could be realized simultaneously by reasonably controlling the content of titanium in silver and titanium co-doped carbon-based composite films. [ABSTRACT FROM AUTHOR]

Objective To evaluate the clinical effect of integrated Traditional Chinese and Western medicine on abdominal distention and constipation after surgery for thoracolumbar fracture. Methods The CNKI, CBM, VIP and Wanfang Date databases were searched by computer. Randomized controlled trials (RCTs) on the efficacy of integrated Traditional Chinese and Western medicine in the treatment of abdominal distention and constipation after surgery for thoracolumbar fracture were included. RevMan 5. 4 software was used for data analysis from database construction to March 2022, and Jadad scale was used to evaluate the literature quality and funnel plot was used to analyze whether there were publication offset results in the included literature. Results After screening, 7 literatures were included, including 590 subjects: 301 in the experimental group and 289 in the control group. Meta-analysis showed that the nursing measures of integrated Traditional Chinese and Western medicine were significantly better than conventional nursing measures in treating and relieving postoperative abdominal distention and constipation(P＜0. 05). Conclusion Based on the current clinical evidence, the full application of the dialectical theory of traditional Chinese medicine and the adoption of appropriate Chinese medicine prescriptions combined with routine orthopedic nursing measures can effectively relieve the symptoms of abdominal distension and constipation in patients with thoracolumbar fracture after surgery, relieve discomfort and improve nursing satisfaction, which can provide clinical reference (目的 通过Meta分析系统评价中西医结合治疗胸腰段骨折术后腹胀便秘的临床效果。方法 计算机检索中国知网(CNKI)、中国生物医学文献库(CBM)、维普数据库(VIP)和万方数据(Wanfang Data)数据库, 纳入中西医结合治疗胸腰段骨折术后腹胀便秘疗效的随机对照试验(RCTs), 选取文献时间从建库至2022年3月。采用RevMan 5. 4软件进行数据分析、Jadad量表对文献质量进行评价、漏斗图分析纳入的文献是否存在发表偏移。结果 经筛选后最终纳入7个文献, 共590人, 试验组301人, 对照组289人。Meta分析结果表明中西医结合的护理措施在治疗和缓解患者术后腹胀便秘的症状明显优于常规护理措施(P＜0. 05)。结论 基于目前临床证据表明, 充分应用中医辨证论治理论, 采用合适的中药方剂结合骨科护理常规等措施, 能有效缓解胸腰段骨折术后患者腹胀便秘症状, 减轻不适感, 提高护理满意度, 可为临床提供参考。)

Featured Application: The research provides a theoretical reference for transformer closing-control strategies, in which the superposition effect decreases as the reclosing interval increases. When a transformer suffers a permanent fault, it will suffer a short-circuit impulse again after reclosing. If the previous vibration of the winding is not attenuated completely and the winding is subjected to a secondary impulse within a short time, the secondary vibration response will have a superposition. The aim of this study was to analyze the effect of the anti-short-circuit ability of operational transformers subjected to a secondary short-circuit current impulse. In this paper, a model is established for calculating axial vibration in transformer windings and effects on the vibration response of windings under different closing phase angles and short-circuit intervals are analyzed. The results show that the vibration acceleration of windings is a V-shaped variation at phase angles from 0° to 180°, reaching the maximum values at 0° and 180° and reaching the minimum value at 90°. When the transformer recloses on a permanent short circuit, due to the superposition effect, the vibration acceleration amplitude of the secondary impulse will be greater than that of the primary impulse, but as the reclosing interval increases, the superposition effect decreases continuously. When the interval is 600 ms, the superposition effect for the vibration acceleration of the secondary impulse attenuates to 83.3%. The superposition effect is not significant after 600 ms. The research provides a theoretical reference for transformer closing-control strategies. [ABSTRACT FROM AUTHOR]

To improve the performances of AlGaN solar‐blind ultraviolet (UV) avalanche photodetectors (APDs), we propose a separate absorption and multiplication (SAM) AlGaN APD with a gradually doped charge layer. The calculation results indicate that the designed APD can significantly increase the maximum gain by almost 40%, and reduce the breakdown voltage by about 9% compared with the conventional AlGaN APD. The parameters of multiplication layer and p‐type layer are optimized, and the physical mechanism is described in detail, which provides theoretical guidance for high‐performance device structure design and experimental preparation. [ABSTRACT FROM AUTHOR]

Human body temperature not only reflects vital signs, but also affects the state of various organs through blood circulation, and even affects lifespan. Here a wireless body temperature detection scheme was presented that the temperature was extracted by investigating the out-of-plane (OP) ferromagnetic resonance (FMR) field of 10.2 nm thick La0.7Sr0.3MnO3 (LSMO) film using electron paramagnetic resonance (EPR) technique. Within the range of 34–42 °C, the OP FMR field changes linearly with the increasing or decreasing temperature, and this variation comes from the linear responses of magnetization to the fluctuant temperature. Using this method, a tiny temperature change (< 0.1 °C) of organisms can be detected accurately and sensitively, which shows great potential in body temperature monitoring for humans and mammals. [ABSTRACT FROM AUTHOR]

Obesity is associated with an increasing tendency which is a typical metabolic syndrome resulting from metabolic disorders due to the excessive food intake, and thus leading to a citical threat to human health. Studies were proved that food reward was an important factor affecting feeding behavior and played a key role in the occurrence and development of obesity. Recent studies indicated that brain-gut peptide, leptin, insulin and gut microflora could directly or indirectly regulate appetite and stabilize body weight through dialogue between intestine and brain, which mediated a crucial role in preventing obesity. Therefore, this review highlighted the role of the dialogue between intestine and brain in food reward and expanded strategies for the prevention and treatment of obesity. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) MoS2 was grown on AlGaN(GaN) substrates by chemical vapor deposition (CVD) and 2D-3D MoS2-AlGaN(GaN) heterostructures were formed. The MoS2 crystal on AlGaN surface has a mixed and irregular shape including single and multiple layers, while the single layer of triangular MoS2 is basically prepared on GaN surface. Combined with theoretical first-principles analysis, it is found the adsorption of AlGaN to MoS2 is lower than that of GaN, which leads to the deposition of MoS2 molecules on AlGaN surface, forming multilayer shapes. In addition, Both the MoS2-AlGaN(GaN) heterostructures exhibit indirect band gaps and broad-band light absorption performances. [ABSTRACT FROM AUTHOR]

The ultrahigh flexibility and elasticity achieved in freestanding single-crystalline ferroelectric oxide membranes have attracted much attention recently. However, for antiferroelectric oxides, the flexibility limit and fundamental mechanism in their freestanding membranes are still not explored clearly. Here, we successfully fabricate freestanding single-crystalline PbZrO 3 membranes by a water-soluble sacrificial layer technique. They exhibit good antiferroelectricity and have a commensurate/incommensurate modulated microstructure. Moreover, they also have good shape recoverability when bending with a small radius of curvature (about 2.4 μm for the thickness of 120 nm), corresponding to a bending strain of 2.5%. They could tolerate a maximum bending strain as large as 3.5%, far beyond their bulk counterpart. Our atomistic simulations reveal that this remarkable flexibility originates from the antiferroelectric-ferroelectric phase transition with the aid of polarization rotation. This study not only suggests the mechanism of antiferroelectric oxides to achieve high flexibility but also paves the way for potential applications in flexible electronics., (© 2024. The Author(s).)