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The western margin of the Ordos Basin and its adjacent regions have undergone a complex tectonic evolution from the Mesozoic to the Cenozoic era. However, the question of tectonic uplift since the Cenozoic era remains a topic of contention, and the regional thermal evolution history necessitates precise chronological evidence. Situated close to the thrust belt within the western margin of the Ordos Basin, the Niushoushan-Luoshan area holds pivotal significance in unraveling the Mesozoic tectonic events within the basin's confines. Through a meticulous exploration employing apatite fission track (AFT) analysis and thermal history simulation, this study delineates the Mesozoic uplift sequence and its temporal confines in the Niushoushan-Luoshan area. The results reveal that the Mesozoic uplift within this region predominantly occurred during the Middle Jurassic period (170 Ma) to the end of the Early Cretaceous (110 Ma). Furthermore, we observe a slightly earlier onset of uplift in the Luoshan area (170 Ma) compared to the Niushoushan area (160 Ma). This uplift is primarily attributed to the north-eastward extrusion of the Qilian orogenic belt. Combining our findings with existing research, we propose that the Cenozoic uplift in the western margin of the Ordos Basin and its adjacent areas started during the Late Triassic, comprising two distinct phases: the first phase unfolding from the Late Triassic (220 Ma) to the end of the Early Jurassic (185 Ma), and the second phase occurring from the Middle Jurassic (175 Ma) to the end of the Early Cretaceous (110 Ma); the uplift in the Niushoushan-Luoshan area is part of the second phase of uplift along the western margin of the Ordos Basin. The two Cenozoic tectonic uplift phases along the western margin of the Ordos Basin display characteristics of north-to-south and southwest-to-northeast propagation, respectively. It is inferred to be associated with the Late Triassic collision between the North China and South China blocks, as well as the movement of the Lhasa Block converging toward the northeast during the Middle to Late Jurassic.

Seabed fluid migration is a critical process that involves the transport and movement of liquids, gases, and seawater within and outside the seabed, which has significant impacts on the genesis, development, and evolution of seabed geological disasters. Notably, typical disasters such as submarine landslides in the sea area of China demonstrate a strong relevance with seabed fluid migration phenomena. In this paper, we analyze the distribution characteristics of typical fluid migration system types and geological disaster causes taking the northern South China Sea as an example, and we summarize the observation and investigation methods of seabed fluid migration. Furthermore, we propose the primary issues and content that must be addressed in the study of disasters induced by seabed fluid migration and their prevention and control. Specifically, we suggest that research should focus on the three phases, namely disaster genesis induced by deep high-pressure fluid migration, disaster development caused by gas hydrate decomposition and fluid migration, and disaster triggering resulting from ocean water movement. Based on breakthroughs in technological bottlenecks such as multi-system integration, multi-scale cooperation, and multi-dimensional information processing in deep-sea exploration, we must conduct in-depth research on the evolution mechanisms of seabed disaster genesis, development, and triggering under the influence of seabed fluid migration. Additionally, we must develop theoretical methods for seabed disaster risk prevention and control under the coupled effects of seabed fluid migration, geological environment, and human activities.

Against the background of strengthening the marine industry, China’s marine resource development activities have gradually extended to the deep sea. However, due to harsh geological conditions, major submarine geological hazards pose constraints on marine resource evelopment and engineering. It is necessary to comprehensively understand the typical characteristics and causallaws of submarine geological hazards and summarize the monitoring techniques and methods for typical submarine geological hazards. This study provides an overview of the research history of submarine geological hazards and their monitoring. It summarizes the common types and characteristics of submarine geological hazards, and reviews the research on the mechanisms of submarine geological hazard evolution as well as the progress in monitoring techniques and networks for submarine geological hazards. The study suggests that it is important to improve the evaluation theory and methods of submarine geological hazards in circumcontinental shelf basins, strengthen the study of disaster mechanisms and prediction for these hazards, and conduct research on detection and monitoring methods and precursory identification of submarine geological hazards to enhance our understanding of key scientific issues. Furthermore, the study emphasizes the need to establish a comprehensive database of submarine geological hazards in the circumcontinental shelf basins, create a detailed information repository of submarine resource distribution and engineering facilities in the South China Sea’s circumcontinental shelf area, develop visualization and simulation techniques for the dynamic evolution process of submarine geological hazards, and construct a multi-level and multi-hazard cooperative monitoring system and early warning network for submarine geological hazards, aiming to overcome key technological bottlenecks.

In this work, a dynamic model considering time-varying mesh stiffness and backlash was proposed and a test rig was built to investigate the vibration behavior of the idle gear set in a gerotor pump. The effects of input shaft speed, torque fluctuation, and gear tooth backlash on the dynamic performance of gerotor pump were analyzed according to the numerical and experimental results. Results demonstrate that when the torque fluctuation is neglected, the dynamic transmission error of drive gear is dominated by the first three mesh harmonic components; however, the RMS values of vibration acceleration have high frequency characteristics. When the torque fluctuation is considered, the dynamic responses of gerotor pump are modulated by the torque fluctuation. The effect of tooth backlash on the dynamic performance of gerotor pump is limited and mostly depended on the torque fluctuation condition. The gerotor pump noise is dominated by the low frequency component around the mesh frequency. The vibration energy can be divided into two parts in the frequency domain. In the low frequency band, the vibration energy is caused by the mechanical vibration. However, in the high frequency band, the cavitation phenomena may cause the concentration of the vibration energy and resonant of pump structure. [ABSTRACT FROM AUTHOR]

Context: Few studies have directly compared the cognitive characteristics of patients with mild autonomous cortisol secretion (MACS) and Cushing's syndrome (CS). The effect of surgical or conservative treatment on cognitive function in patients with MACS is still unclear., Objective: To compare the differences in cognitive function between patients with MACS and CS and evaluate the effect of surgery or conservative treatment on cognitive function., Methods: We prospectively recruited 59 patients with nonfunctional adrenal adenoma (NFA), 36 patients with MACS, and 20 patients with adrenal CS who completed the global cognition and cognitive subdomains assessments. Seventeen MACS patients were re-evaluated for cognitive function after a 12-month follow-up period; of these, eleven underwent laparoscopic adrenalectomy and six received conservative treatment., Results: Patients with MACS and CS performed worse in the global cognition and multiple cognitive domains than those with NFA (all P<0.05). No statistical difference was found in cognitive functions between patients with MACS and CS. Logistic regression analysis showed that patients with MACS (odds ratio [OR]=3.738, 95% confidence intervals [CI]: 1.329-10.515, P=0.012) and CS (OR=6.026, 95% CI: 1.411-25.730, P=0.015) were associated with an increased risk of immediate memory impairment. Visuospatial/constructional, immediate and delayed memory scores of MACS patients were significantly improved at 12 months compared with pre-operation in the surgical treatment group (all P<0.05), whereas there was no improvement in the conservative treatment group., Conclusion: Patients with MACS have comparable cognitive impairment as patients with CS. Cognitive function was partially improved in patients with MACS after adrenalectomy. The current data support the inclusion of cognitive function assessment in the clinical management of patients with MACS., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Liu, Zhao, Zhang, Tian, Zhang, Lou, Zhang, Yang, Zhu and Li.)