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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]

As China transitions into a deeply aging society, the elderly population's growth has driven a rapid increase in elderly care institutions and facilities during the "13th Five-Year Plan" period, rising by over 235% compared to the "12th Five-Year Plan". The ongoing normalization of COVID-19 prevention measures has underscored the urgent need to improve natural ventilation in elderly care residential facilities. This study conducted empirical surveys to assess the current state of natural ventilation in typical elderly care facilities and analyzed the architectural elements influencing it. By examining the needs and preferences of the elderly for natural ventilation, two basic living space layout types were identified through typological analysis. Suitable CFD simulation software was then employed to model key elements, and effective methods to enhance ventilation were summarized. This study found that modifying the floor plan to reduce the depth of south-facing rooms to 8.4 m, relocating external openings to the center of the rooms, adjusting the ratio of ventilation openings to room area to greater than 1/12, and adding 0.5 m high windows facing internal traffic roads can significantly improve indoor ventilation while maintaining privacy. Furthermore, placing the main activity and resting areas of the elderly in well-ventilated zones with minimal drafts can enhance both comfort and ventilation effectiveness. The research provides a scientific basis and methodological guidance for the construction and renovation of elderly care residential facilities. [ABSTRACT FROM AUTHOR]

Heat shock transcription factor (Hsf) plays a pivotal role in promoting rapid heat‐induced transcriptional reprogramming in plants. The thermotolerance regulatory function of Hsfs is influenced by their own alternative splicing. In this study, we found that ZmHsf17‐II, an intron retention isoform of subclass A2 gene ZmHsf17 of maize (Zea mays), accumulated in large amounts as a result of severe or sustained heat stress. It was confirmed by expression and purification that ZmHsf17‐II encodes a small truncated peptide with 115 amino acids. ZmHsf17‐II was found to be located in the nucleus and have no transcriptional activity. Overexpressing ZmHsf17‐I in Arabidopsis could enhance plants' thermotolerance, while overexpressing ZmHsf17‐II does not. Based on the results of molecular docking, Y2H and split LUC experiments, we found that ZmHsf17‐II could bind to DBD region of ZmHsf17‐I through the hydrogen bond interaction between the truncated DBD of ZmHsf17‐II and three amino acid residues (Arg105, Thr109 and Lys142) of ZmHsf17‐I DBD region. Further experiments showed that ZmHsf17‐I could bind to its own promoter and exhibited transcriptional activation activity, while ZmHsf17‐I interaction with ZmHsf17‐II, transcriptional activation activity was interfered. Those findings indicate that ZmHsf17 can negatively regulate its own transcription by producing more intron retention isoforms via alternative splicing under heat stress. [ABSTRACT FROM AUTHOR]