Ischemia-reperfusion injury (IRI) is an inherent issue in organ transplantation. Because of the allograft shortage, more and more extended criteria donor (ECD) organs are used, unfortunately these grafts are more susceptible to IRI. Although machine perfusion technology has brought hope to alleviate IRI, this technology is still unable to eradicate IRI-related organ damage. Ischemia-free liver transplantation (IFLT) can completely avoid IRI, thereby improve graft function and recipient outcome, and allow to expand organ pool. This review summarized the latest progresses in IFLT, and speculated the future development of this concept.
Global climate change has intensified the water cycle, leading to frequent extreme precipitation events, posing a significant threat to railway infrastructure and safety operations. Based on the analysis of past and future precipitation changes in China, this study investigates the impact of climate change on railway safety operations. The study reveals the following findings: (1) Under the influence of the intensified East Asian summer monsoon and the northward shift of the subtropical high during the 2017–2021 compared to the 2012–2016, precipitation has significantly decreased (120 mm) in the regions south of the Yangtze River and South China, while it has increased (60 mm) in the regions from the eastern of Northwest China to the middle and lower reaches of Yangtze River; The operational precipitation risk has decreased for Urumqi, Lanzhou, Qinghai-Tibet Group, Xi’an, and Wuhan railway bureaus (abbreviated as Bureau), while it has increased for Nanchang, Chengdu, Zhengzhou, Shanghai, and Shenyang Bureaus. Particularly noteworthy is that despite a decrease in total annual precipitation for Nanchang bureau (15.3 mm/a), the frequency of intense precipitation events has increased, leading to an increased operational precipitation risk. (2) During the 21st century, under high (SSP5-8.5), medium (SSP2-4.5), and low (SSP1-2.6) forcing scenarios, all projections indicate that most of the China will experience an increasing trend in precipitation, with significant increases in precipitation observed in the regions south of the Yangtze Rive, South and Southwest China. The higher the greenhouse gas emissions, the more pronounced the increasing trend in precipitation. (3) Compared to the 20th century, under high (SSP5-8.5), medium (SSP2-4.5), and low (SSP1-2.6) forcing scenarios, all projections indicate that the total annual precipitation hours, railway inspection, speed limit, and closure risk hours have all increased on a national scale during the 21st century. The operational precipitation risk for railways has also increased. The higher the alert level for railway precipitation (precipitation < inspection < speed limit < closure), the higher the proportion of risk hours compared to the 20th century. By the late 21st century, the railway inspection, speed limit, and closure risk hours have increased by 175%, 463%, and 647%, respectively, compared to the 20th century.
Next Generation Train Control System (NGTC) based on train-train communication can efficiently realize train tracking control through constant distance strategy. How to ensure the stability of the platoon with the control strategy is very crucial since the leader train action is random in the platoon control. Based on Stochastic Priced Timed Game (SPTG), we propose a train-train communication control strategy modeling and verification method. Firstly, according to the control strategy's requirements, a platoon control model including a leader train and follower trains are established and the stability are verified by SPTG automata. Secondly, using time expansion as the cost function, the optimal operation strategy of the platoon is obtained through combination of the cooperative game of the platoon's SPTG automata model and Q-learning. Finally, the stability optimization objection of the platoon is simulated in single-train operation, two-train operation and multi-train operation tracking scenarios. Compared with the random operation of the platoon, the result shows that this method can make the platoon stability error smaller.
技术在养老领域的应用一直是研究人员关注的焦点,基于对老年群体生理和认知层面自然衰老规律,梳理了适老化设计的研究方法的演化与发展,总结了更具人文关怀的科技适老化设计要素.对智能技术支持老年人拍照、运动和居家照护的3个场景进行了设计调研,挖掘了设计过程中要关注的发展方向.分析表明,在交互设计方面,应充分考虑老年人的感官状态,采用简洁友好的界面和多模态交互方式;在人文关怀方面,关注老年人对于科技的接受程度和使用时的情感体验,有助于老年人更好地融入数字化时代.
表面光催化材料广泛用于表面自清洁、污水处理、水制氢等领域.特别是复合半导体纳米材料,利用p-n结原理可以大幅度提高表面自由电子和电子空穴浓度,从而提高吸收太阳光的能力,具有广阔的应用前景.阐述了纳米光催化材料领域的研究进展,以及在食品包装、医疗器械、交通设备及建筑材料领域抗菌自清洁的应用前景.
