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To evaluate the crack sensitivity of Q350EW high-chromium weathering resistant steel during continuous cast⁃ ing， the high-temperature thermoplastic characteristics of Q350EW high-chromium weathering resistant steel were studied using Gleeble3500 thermal simulation testing machine， and the distribution of precipitates in the steel was calculated us⁃ ing Thermo-Calc thermodynamic software. Scanning electron microscopy and optical microscopy were used to observe and analyze the macrostructure and microstructure morphology of high-temperature tensile fractures and microstructure at the fractures. The research results indicate that as the heating temperature increases， the tensile strength of the test steel de⁃ creases； The cross-sectional shrinkage curve shows a concave valley around 700 ℃-800 ℃， with the lowest cross-sectional shrinkage of 64. 9% at 775 ℃. The fracture morphology within the range of concave valley temperature is mainly composed of ductile dimples， and its fracture mechanism is ductile fracture. Microscopic analysis shows that ferrite appears at the grain boundaries of the original austenite， leading to a decrease in plasticity. However， due to the high content of ferrite， the plasticity of Q350EW high chromium weather resistant steel still remains at a high level. By optimizing key process pa⁃ rameters such as secondary cooling during continuous casting， the risk of cracking in Q350EW high chromium weather re⁃ sistant steel billets can be reduced. It is recommended that the temperature of the corner bending and straightening section of the billets be less than 750 ℃.

Objective To study the optimization measures for treating waterlogged collapsible loess stratum, it is necessary to investigate the deformation characteristics of tunnel structures after loess collapse by waterlogging. Method The foundation treatment for the waterlogged collapsible loess tunnels is introduced. Taking a shield metro tunnel crossing through waterlogged collapsible loess stratum as example, the method of three-axis mixing pile is adopted as the foundation treatment method. By establishing a numerical calculation model using MIDAS GTS software， the influence of waterlogged deformation of loess foundation on the vertical displacement of various metro tunnel structure parts and the internal force of lining structure is analyzed under different treatment depths and treatment widths. The treatment scheme is optimized based on the changing trends of tunnel parts vertical displacement and lining structure internal force, the construction economy and relevant requirements. Under conditions of three treatment widths and seven treatment depths, variation laws of vertical displacement, bending moment, and principal stress at the tunnel arch waist, vault, and invert are analyzed for the most suitable treatment recommendation. Result & Conclusion The greater the treatment depth, the smaller the vertical displacement of tunnel structure parts and the larger the lining structure internal force; the larger the treatment width, the smaller the vertical displacement and the internal force mentioned above. In this case study engineering, the optimal treatment depth is 7 m, and the optimal treatment width is 16 m.

Background The hypertensive population has a large base in China, and its preventive and treatment measures rely mainly on the chronic disease management service program within the National Basic Public Health Service. However, current studies have shown low utilization rate of it, so it is of great significance for improving the participation of the National Chronic Disease Management Service and health level in the hypertensive population to conduct a survey of participants to determine the factors affecting their treatment adherence. Objective To investigate and analyze the current status and influencing factors of treatment adherence of hypertension management services within the National Basic Public Health Service, and provide reference for improving treatment adherence in hypertensive patients. Methods A total of 295 participants of hypertension management services in the community served by a community healthcare center in Guangzhou City from June to September 2022 as the study subjects by using a multi-stage sampling method. The General Information Questionnaire and the Emotional Balance Scale (positive and negative emotions) were used to investigate the basic information of the study subjects, and the Hypertension Treatment Adherence Scale was used to investigate the current status of treatment adherence among the study subjects. Multivariate Logistic regression analysis was used to explore the influencing factors of treatment adherence to the National Chronic Disease Management Service in the hypertensive population, and the influence of the combined positive and negative emotion status on treatment adherence to the National Chronic Disease Management Service in the hypertensive population. Results A total of 310 valid questionnaires were distributed, 295 valid questionnaires were recovered, with a validity rate of 95.2%; the total score of the Hypertension Treatment Adherence Scale was (94.24±8.67), of which the score of medication adherence was (21.06±2.45), medication malpractice was (31.33±3.90), tobacco and alcohol management was (8.44±1.88), and management of daily life was (33.41±4.61), with good adherence rate of 52.2% (154/295) ; the positive emotion score in the Emotional Balance Scale was (3.76±1.02), and the negative emotion score was (2.63±1.12) ; the results of multivariate Logistic regression analysis showed that gender, age, BMI, education level, blood pressure control, self-perceived physical condition, satisfaction with the point of care, more positive emotions and less negative emotions were the influencing factors for good treatment adherence to the National Chronic Disease Management Service in the hypertensive population (P

To study the mechanism of sand surge disaster in tunnel construction in the Neoproterozoic sandstone stratum and to develop corresponding treatment measures, the Xiangshan Tunnel of the Yinchuan-Lanzhou High-speed Railway was taken as the research object. Firstly, the sand surge phenomenon during the construction process were analyzed, quantitative analysis of the composition of the surrounding rock particle size, the water content of the rock layer, mud content was made and the mechanism of the sand surge in this type of stratum was researched. Secondly, the reinforcement measures taken after the disaster occurred were summarized, and the reasons that the reinforcement measures adopted in the process failed to meet expectations were analyzed. Finally, the curtain grouting + surface precipitation program was explained. Through the study, it is concluded that: (1) The phenomenon of sand gushing in the Neoproterozoic soft rock tunnel is mainly related to the particle size, water content, mud content, and force on the critical surface. (2) When the sand layer water content increased to 20%, the phenomenon of sand surge intensified leading to large area slip. (3) For different sizes of the sand surge to take a small conduit in advance combined with backward grouting way reinforcement and cave precipitation measures, due to the high content of fine sand and the impact of groundwater, the effects do not reach expectations. (4) Curtain grouting and surface precipitation are used to reinforce the surrounding rock, which achieve the expected effect. [ABSTRACT FROM AUTHOR]

Objective: To explore the risk factors for Type 1 cardio-renal syndrome (CRS1) after ST-segment elevation myocardial infarction (STEMI)., Methods: A total of 378 patients with STEMI were divided into two groups: a CRS1 group (n=98) and a non-CRS1 group (n=280). Clinical characteristics in the 2 groups were compared, and independent risk factors for CRS1 after STEMI were analyzed, and the effect of emergency percutaneous coronary intervention (PCI) on CRS1 in patients after STEMI were assessed., Results: In the 378 STEMI patients, CRS1 was found in 98 patients (25.9%). Between the 2 groups, there was significant difference in 12 parameters, including age, history of diabetes, admission mean arterial pressure, admission systolic blood pressure, admission heart rate, Killip classification, left ventricular ejection fraction, baseline serum creatinine, baseline evaluated glomerular filtration rate (eGFR), emergency PCI, β-blockers and angiotensin converting enzyme inhibitor/angiotensin, receptor antagonist (ACEI/ARB) application (all P<0.05). Multivariate logistic regression showed that age, history of diabetes, admission systolic blood pressure, Killip classification, reduced left ventricular ejection fraction, reduced eGFR, emergency PCI nonundergo and ACEI/ARB non-use were independent risk factors for CRS1 after STEMI. In the 256 patients undergoing emergency PCI, 50 patients (19.5%) had CRS1. The door-ball time and the amount of contrast agent in the CRS1 group were significantly higher than those in the non- CRS1 group (both P<0.05), but there was no significant difference in the blood flow in the "culprit vessel" after the PCI (P>0.05)., Conclusion: CRS1 is a common complication of STEMI, which is associated with many factors. Immediate revascularization can reduce the incidence of CRS1 in patients with ST-segment elevation myocardial infarction.

Objective: To estimate the therapeutic effect and safety of intra-aortic balloon pumps (IABP) in patients with serious cardiovascular diseases., Methods: We retrospectively analyzed the clinical data of 68 patients with serious cardiovascular diseases, who were enrolled in Hunan Provincial People's Hospital between 2009 and 2011. All patients received IABP support. The systolic blood pressure, diastolic blood pressure,heart rate, N-terminal precursor of brain natriuretic peptide (NT-proBNP), and renal function of all patients were determined before and after the IABP. Cardiac events and mortality were observed after IABP support., Results: The disease in 51 patients improved after IABP support. The systolic blood pressure, diastolic blood pressure,heart rate, and NT-proBNP were significantly lower than those before the IABP. Thirty-seven patients with acute myocardial infarction successfully completed percutaneous coronary intervention surgery after the IABP support. Five patients had IABP-related complications, but no serious complication occurred., Conclusion: IABP is an effective and safe procedure for critical cardiovascular patients. IABP should be applied early for the patients with appropriate indications.

Objective: To construct a plasmid for analyzing gene functions and expressions and to study the MXAN1334 gene in Myxococcus xanthus with the plasmid., Methods: We constructed the plasmid vector pZCY11, amplified MXAN1334 gene fragment from M. xanthus DK1622 by PCR, and inserted the fragment into a site upstream of lacZ, resulting in the recombinant plasmid pZCY13. The plasmid pZCY13 was transformed by electroporation to DK1622, producing a mutant ZC16-18 (deltaMXAN1334)., Results: The plasmid pZCY11 carried the resistance gene aph as the selectable marker, the replication origin of OriR6K and promoterless reporter gene lacZ. We examined the swarm expansions of ZC16-18 on CTT hard and soft agar, and the result indicated that MXAN1334 gene was probably involved in gliding motility in M. xanthus. In addition, beta-galactosidase activity of ZC16-18 was detected by X-gal assay and the blue color developed was used to mark the colony growth. Time of colour showed that MXAN1334 gene was expressed in the early stage in M. xanthus., Conclusion: The plasmid vector pZCY11 made it more convenient for the study on functions and the expressions of target gene in M. xanthus.