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In response to the challenges of poor engineering properties and the high difficulty in improving peat soil, a composite cement solidification agent (CCS) comprising ultra-fine cement (UFC) and ordinary Portland cement (OPC) was proposed for the solidification of simulated peat soil. The influence of UFC on the permeability of cement-soil samples was investigated through osmotic pressure tests and X-ray diffraction (XRD) experiments. Osmotic pressure tests results indicate that, under constant CCS dosage, the permeability coefficient k of specimens decreases with increasing UFC mass fraction, with a significant attenuation of the decreasing trend observed when the UFC mass fraction exceeds 12%. For CCS with a UFC mass fraction of 12%, k decreases with increasing CCS dosage, and the declining trend is notably attenuated when the dosage exceeds 25%. XRD results indicate that the diffraction peak intensity of calcium silicate hydrate (C-S-H) in the samples increases with both the increase in the UFC mass fraction and the curing time. Compared to OPC, CCS achieves superior solidification efficiency with a reduced cement dosage, facilitating the attainment of carbon reduction objectives. [ABSTRACT FROM AUTHOR]

Objective: To analyze the predictors of successful weaning off extracorporeal membrane oxygenation (ECMO) after extracorporeal cardiopulmonary resuscitation (ECPR)., Methods: The clinical data of 56 patients with cardiac arrest who underwent ECPR in Hunan Provincial People's Hospital (the First Affiliated Hospital of Hunan Normal University) from July 2018 to September 2022 were retrospectively analyzed. According to whether ECMO was successfully weaning off, patients were divided into the successful weaning off group and the failed weaning off group. The basic data, duration of conventional cardiopulmonary resuscitation (CCPR, the time from cardiopulmonary resuscitation to ECMO), duration of ECMO, pulse pressure loss, complications, and the use of distal perfusion tube and intra-aortic balloon pump (IABP) were compared between the two groups. Univariate and multivariate Logistic regression analyses were performed to identify the risk factors for weaning failure of ECMO., Results: Twenty-three patients (41.07%) were successfully weaned from ECMO. Compared with the successful weaning off group, patients in the failed weaning off group were older (years old: 46.7±15.6 vs. 37.8±16.8, P < 0.05), higher incidence of pulse pressure loss and ECMO complications [81.8% (27/33) vs. 21.7% (5/23), 84.8% (28/33) vs. 39.1% (9/23), both P < 0.01], and longer CCPR time (minutes: 72.3±19.5 vs. 54.4±24.6, P < 0.01), shorter duration of ECMO support (hours: 87.3±81.1 vs. 147.7±50.8, P < 0.01), and worse improvement in arterial blood pH and lactic acid (Lac) levels after ECPR support [pH: 7.1±0.1 vs. 7.3±0.1, Lac (mmol/L): 12.6±2.4 vs. 8.9±2.1, both P < 0.01]. There were no significant differences in the utilization rate of distal perfusion tube and IABP between the two groups. Univariate Logistic regression analysis showed that the factors affecting the weaning off ECMO of ECPR patients were pulse pressure loss, ECMO complications, arterial blood pH and Lac after installation [pulse pressure loss: odds ratio (OR) = 3.37, 95% confidence interval (95%CI) was 1.39-8.17, P = 0.007; ECMO complications: OR = 2.88, 95%CI was 1.11-7.45, P = 0.030; pH after installation: OR = 0.01, 95%CI was 0.00-0.16, P = 0.002; Lac after installation: OR = 1.21, 95%CI was 1.06-1.37, P = 0.003]. After adjusting for the effects of age, gender, ECMO complications, arterial blood pH and Lac after installation, and CCPR time, showed that pulse pressure loss was an independent predictor of weaning failure in ECPR patients (OR = 1.27, 95%CI was 1.01-1.61, P = 0.049)., Conclusions: Early loss of pulse pressure after ECPR is an independent predictor of failed weaning off ECMO in ECPR patients. Strengthening hemodynamic monitoring and management after ECPR is very important for the successful weaning off ECMO in ECPR.

Objective: To investigate the pre-treatment preventive maintenance and quality control procedure of MRI system and transcranial MRI-guided focused ultrasound (TcMRgFUS) treatment system by monitoring quality control of these two systems., Methods: The general performance index and image quality control index of MRI system, as well as the quality assurance program of TcMRgFUS EXABLATE 4000 system were tested and recorded., Results: The general performance index and image quality control index of MRI system met requirements., Conclusions: Through system detection, the system performance could be monitored, ensuring the accuracy and safety of surgery.