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Objectives: Lanzhou New Area is an important window for the development of northwest China. In recent years, the large‐scale construction of mountain excavation and city construction project has led to different degrees of land subsidence, which has seriously threatened the economic and social development of the new area. Methods: Taking Lanzhou New Area as the research object, this paper uses small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) to process 58 ascending Sentinel-1A image data covering the study area from May 2017 to February 2021. The distribution characteristics and spatio temporal evolution of land subsidence in the study area were obtained, and the SBAS-InSAR measurement results were verified by field investigation. Then the related factors affecting land subsidence were discussed. Results: The results show that land subsidence in Lanzhou New Area is mainly concentrated in mountain excavation and city construction area, with an area of about 33.5 km² and a maximum subsidence rate of-68 mm/a. In space, with the development of excavation and filling projects, the land subsidence develops to the southeast of the new district, and the land surface presents a long‐term continuous settlement process. Conclusions: Land subsidence is closely related to many factors such as mountain excavation and city construction project, thickness of excavation and filling, geology and road. Specifically, mountain excavation and city construction project control the spatial extent of land subsidence, and then the filling thickness control the magnitude of land subsidence. The nature of artificial fill is an intrinsic factor causing land subsidence, while road construction will also accelerate the process of land subsidence. The research results can provide scientific basis for the sustainable and safe development of the new district and urban planning and construction. [ABSTRACT FROM AUTHOR]

Objective: To evaluate and compare the effects of intradialytic cycling and respiratory training on exercise endurance, pulmonary function and quality of life of maintenance hemodialysis(MHD)patients. Method: From July 2022 to July 2023, 60 MHD patients in our hospital were randomly divided into control group (n=20), cycling group (n=20), and respiratory group (n=20). The control group was given routine hemodialysis treatment. The cycling group was given moderate-intensity intradialytic cycling training on the basis of routine hemodialysis treatment, for 12 weeks, 3 times a week, 40 minutes each time. The respiratory group was given respiratory training (abdominal breathing exercise, pursed-lip breathing exercise and diaphrag matic breathing exercise) on the basis of routine hemodialysis treatment, for 12 weeks, 3 times a week, 40 minutes each time. VO2peak, AT and VO2/HRpeak were used to evaluate the exercise endurance. FVC, FEV1 and MVV were used to evaluate the pulmonary function, which were expressed as a percentage of the predicted values, i.e. FVC%, FEV1%, MVV%. SF-36 was used to assess the quality of life, which includes PCS, MCS and total score. Result: There were no significant difference in VO2peak, AT, VO2/HRpeak, FVC%, FEV1%, MVV%, PCS, MCS and total score among the three groups before intervention(P>0.05); after 12 weeks of intervention, VO2peak, AT, VO2/HRpeak, PCS, and total score of the cycling group were increased compared with those before intervention and were better than that of the control group (P<0.05); FVC%, FEV1%, MCS, and total score of the respiratory group were increased compared with those before intervention and were better than that of the control group(P<0.05). Conclusion: Both intradialytic cycling and respiratory training can improve cardiorespiratory function and quality of life of MHD patients. The intradialytic cycling is more effective in improving exercise endurance and physical health, and respiratory training is more effective in improving lung function and mental health. [ABSTRACT FROM AUTHOR]