Climate warming is likely to weaken the performance of two-phase closed thermosyphon on the Qinghai-Tibet Plateau

Over the years,numerous geotechnical approaches have been implemented to mitigate the adverse effects of climate warming on various infrastructures in the permafrost region of the Qinghai-Tibet Plateau(QTP),such as the Qinghai-Tibet Highway and Railway,and achieved the expected engineering outcomes.However,little attention has been given to whether the performance of these geotechnical approaches has changed during the ongoing process of climate warming.To investigate the performance variation of one of these geotechnical approaches,which is two-phase closed thermosyphon(TPCT),during sustained climate warming,we conducted a statistical analysis of soil temperature monitoring data in 2003-2020 from eight regular embankments and six TPCT embankments in our permafrost monitoring network.The results indicate that TPCT undeniably has a cooling effect on the permafrost beneath embankments,even rapidly eliminated previously formed taliks beneath embankment.However,further analysis reveals that the performance of TPCT has been weakening during sustained climate warming,which has confirmed by the re-forming of the taliks beneath embankment where they had been previously eliminated.Based on the current understanding,we attributed the weakening of thermosyphon performance to a significant reduction in the air temperature freezing index caused by ongoing climate warming.Through this study,we aimed to draw attention to the evolving performance of geotechnical approaches in permafrost regions amid climate warming,prompting necessary engineering innovations to address this situation and ensure the sustainable development of the permafrost region on the QTP.

底泥中的十溴二苯乙烷的短期暴露对斑马鱼胚胎和幼鱼神经毒性的研究（英文）

目的:评估底泥中的十溴二苯乙烷(DBDPE)对斑马鱼早期发育阶段的胚胎毒性和神经行为毒性,并探索其潜在影响机制。创新点:底泥暴露能更真实地反应DBDPE等强疏水性污染物在实际环境中的暴露情况,有利于污染物生态风险评估的科学性和准确性。方法:将受精后4小时(4 hpf)的斑马鱼胚胎置于对照底泥和染毒底泥(DBDPE系列浓度)中进行短期暴露,观察不同发育阶段的存活率、孵化率、畸形率以及行为(包括触碰反应和自由泳动)效应;并通过斑马鱼幼鱼的乙酰胆碱酶活性、神经系统的相关基因(α1-tubulin和gap43)的转录水平以及斑马鱼整体组织的细胞凋亡情况的检测探讨其神经毒性的潜在机制。结论:DBDPE从4 hpf处理至120 hpf,各浓度组的斑马鱼均未出现明显的畸形和死亡。在72 hpf时,最低浓度组(62.5μg/kg)DBDPE轻微加快了斑马鱼的孵化,而最高浓度组(1000.0μg/kg)DBDPE轻微延迟斑马鱼的孵化。所有浓度组的DBDPE对48 hpf时斑马鱼的触碰反应没有任何影响,最高浓度组(1000.0μg/kg)DBDPE对120 hpf时斑马鱼的自由泳动总距离有显著的抑制作用(P<0.05)。但是,斑马鱼的乙酰胆碱酶活性、α1-tubulin和gap43的转录水平未发生显著变化,所有浓度组的DBDPE亦均未诱发斑马鱼整体组织的细胞凋亡。