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Soil moisture (SM) plays a crucial role in the dynamics of coupled atmosphere, water, energy, and carbon cycles. In this study, the spatiotemporal distribution and variations of SM in the Mongolian Plateau were investigated for the period of 1982–2018 based on four gridded SM datasets. Taking the observed SM from 33 monitoring stations as a reference, the reliability of these four gridded products was validated, and the three-cornered hat (TCH) method was also applied to evaluate their uncertainties. Major results indicated that all these four products underestimated the SM in this region at different levels. The ERA-Interim SM performed much better than other three products, with a higher R of 0.53 and lower ubRMSE of 0.0378 m3·m−3. Except for ECV, the surface SM exhibited a decreasing trend at −0.0004 to −0.0008 m3·m−3/decade in the warm season (from April to October) over the past 37 years. The greatest decreases in SM occurred in the summer season. Precipitation change plays a more important role in explaining the variations of SM than temperature reported by partial correlation analysis. The results of this study will benefit our understanding of the climate change effects and the protection of the ecological systems in this region. [ABSTRACT FROM AUTHOR]

The arid and semi‐arid areas in Central Asia have scarce water resources and fragile ecosystems that are especially sensitive and vulnerable to climate change. Reliable information regarding future projections of change in climate is crucial for long‐term planning of water resources management and structural adjustment of agriculture in this region. However, the low‐density meteorological observation network brings great challenges for investigating the effects of climate variations. In this study, variations of precipitation and temperature in Central Asia were examined by a combination of gridded climate dataset of the Climate Research Unit and the latest general circulation models (GCMs) under a representative concentration pathway 4.5. Three downscaling methods, Delta, Advanced Delta, and Bayesian model averaging (BMA) methods, translate the coarse GCMs to local climatic variations for the period 2021–2060 relative to 1965–2004. Major results suggested that the Advanced Delta and BMA methods outperformed the Delta method in precipitation downscaling. Projected precipitation exhibited a general increasing trend at a rate of 4.63 mm/decade for entire Central Asia with strong spatiotemporal heterogeneity. While a declining trend was observed in the southwestern and central parts of Central Asia in summer. The projected temperature was revealed an obvious ascending at 0.37°C/decade, while the warming rate accelerated in higher latitude and mountainous areas. [Correction added on 03 December 2018, after first online publication: The preceding statement has been corrected in this version.] The surface land coverage had significant effects on the variations of precipitation and temperature, respectively. The driven factors of local climate were suggested by analysing the relationships between climate variations and large‐scale atmospheric circulation fields anomalies. The findings of this study aims to provide useful information to improve our understanding for future climate change and benefit local decision makers. The performance of three downscaling methods in terms of precipitation and temperature from general circulation model (GCM) outputs were compared in this study. The relationships between climatic variations and different land cover types were detected based on Land‐Use and Land‐Cover Change (LUCC) and NDVI datasets. The possible drivers of local climatic variations were also suggested by analysing the relationships between local climatic variations and large‐scale atmospheric circulation fields. [ABSTRACT FROM AUTHOR]

The current research proposes a novel method for printing continuous carbon fiber composite parts. At first, continuous carbon fiber prepreg filament for Fused Deposition Modeling 3D printing was manufactured, followed by modification of extruder head of 3D printers to print the filament. Thereafter, three-point flexural test and Response Surface Methodology were adopted to study the mechanical properties of the composite parts printed with the filament. After testing, a mathematical model was developed to describe and analyze the relationship between the printing parameters (printing temperature, printing speed, and layer thickness) and the flexural strength of printed composite parts. We discovered that the flexural strength and flexural modulus of printed composites significantly improved with the proposed method with specified printing parameters, and while of all the parameters, the layer thickness had the greatest contribution towards the final flexural strength. The results indicate that the discussed method could be a promising approach to print CCF composites. [ABSTRACT FROM AUTHOR]

Flooding, one of the most serious natural disasters, poses a significant threat to people's lives and property. At present, the forecasting method uses simple snowmelt accumulation and has certain regional restrictions that limit the accuracy and timeliness of flood simulation and prediction. In this paper, the influence of accumulated temperature (AT) and maximum temperature (MT) on snow melting was considered in order to (1) reclassify the precipitation categories of the watershed using a separation algorithm of rain and snow that incorporates AT and MT, and (2) develop a new snow-melting process utilizing the algorithm in the Soil and Water Assessment Tool Model (SWAT) by considering the effects of AT and MT. The SWAT model was used to simulate snowmelt and flooding in the Tizinafu River Basin (TRB). We found that the modified SWAT model increased the value of the average flood peak flow by 43%, the snowmelt amounts increased by 45%, and the contribution of snowmelt to runoff increased from 44.7% to 54.07%. In comparison, we concluded the snowmelt contribution to runoff, flood peak performance, flood process simulation, model accuracy, and time accuracy. The new method provides a more accurate simulation technique for snowmelt floods and flood simulation. [ABSTRACT FROM AUTHOR]

Objective: To compare the effectiveness of robot-assisted and traditional freehand screw placement in the treatment of atlantoaxial dislocation., Methods: The clinical data of 55 patients with atlantoaxial dislocation who met the selection criteria between January 2021 and January 2024 were retrospectively analyzed. According to different screw placement methods, they were divided into the traditional group (using the traditional freedhand screw placement, 31 cases) and the robot group (using the Mazor X robot-assisted screw placement, 24 cases). There was no significant difference in gender, age, body mass index, etiology, and preoperative visual analogue scale (VAS) score, cervical spine Japanese Orthopaedic Association (JOA) score between the two groups ( P >0.05). The operation time, intraoperative blood loss, operation cost, and intraoperative complications were recorded and compared between the two groups. The VAS score and cervical spine JOA score were used to evaluate the improvement of pain and cervical spinal cord function before operation and at 1 month after operation. CT examination was performed at 3 days after operation, and the accuracy of screw placement was evaluated according to Neo grading criteria., Results: All the 55 patients successfully completed the operation. The operation time, intraoperative blood loss, and operation cost in the robot group were significantly higher than those in the traditional group ( P <0.05). A total of 220 C 1 and C 2 pedicle screws were inserted in the two groups, and 94 were inserted in the robot group, with an accuracy rate of 95.7%, among them, 2 were inserted by traditional freehand screw placement due to bleeding caused by intraoperative slip. And 126 pedicle screws were inserted in the traditional group, with an accuracy rate of 87.3%, which was significantly lower than that in the robot group ( P <0.05). There were 1 case of venous plexus injury in the robot group and 3 cases in the traditional group, which improved after pressure hemostasis treatment. No other intraoperative complication such as vertebral artery injury or spinal cord injury occurred in both groups. All patients were followed up 4-16 months with an average of 6.6 months, and there was no significant difference in the follow-up time between the two groups ( P >0.05). Postoperative neck pain significantly relieved in both groups, and neurological symptoms relieved to varying degrees. The VAS score and cervicle spine JOA score of both groups significantly improved at 1 month after operation when compared with preoperative scores ( P <0.05), and there was no significant difference in the score change between the two groups ( P >0.05)., Conclusion: In the treatment of atlantoaxial dislocation, the accuracy of robot-assisted screw placement is superior to the traditional freedhand screw placement.

Percutaneous Endoscopic Transforaminal Discectomy (PETD) has been widely used for minimally invasive treatment of lumbar disc herniation (LDH), and percutaneous disc target puncture has a steep learning curve and high radiation exposure. Proper technology grafting can improve the surgical procedure and clinical outcomes. The changes brought by grafting surgical robots into PETD are worth investigating. A retrospective analysis was performed on the information of patients who received PETD in our hospital from March 2019 to July 2020. A total of 102 of patients who received 2D-guided robot-assisted PETD were included in Group A, and 102 of patients who received C-arm fluoroscopy-guided bare-handed PETD were included in Group B. The number of punctures, number of fluoroscopies, operation duration, intraoperative anxiety score, complications, and visual analogue scale (VAS) score and Oswestry disability index (ODI) before operation, on Day 1 after operation and at the last follow-up visit of the two groups were compared. All 204 patients received successful operations. Group A received 1.20±0.42 punctures, 10.49±2.16 fluoroscopies and 60.69±5.63 minutes of operation, significantly fewer than the 4.84±1.94 punctures, 17.41±3.23 fluoroscopies and 71.19±5.11 minutes of operation of Group B (all P<0.05), and Group A had significantly lower intraoperative anxiety scores and incidence of complications than Group B (both P<0.05). Both groups had comparable VAS and ODI scores on Day 1 after operation and at the last follow-up visit, which were both significantly higher than those before operation (P<0.05). 2D-guided robot-assisted PETD can enable precise planning of the puncture path, make it easier for operators to complete targeted punctures at pathogenic targets, reduce the number of punctures and fluoroscopies, shorten the operation duration to optimize the operation process, and reduce complications and alleviate intraoperative anxiety for better clinical results. Therefore it mayb be a better choice to assist PETD., Competing Interests: None., (AJTR Copyright © 2022.)