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Objective Bedding deep cutting slopes containing weak interlayers are commonly found in slope engineering, whose stability is influenced by two key factors: The strength of the sliding zone soil and the reserved thickness of the base (the distance from the base of an excavated slope to the weak interlayer). Methods In this research, taking the K42 cutting slope of the Yang-Xuan Expressway as an example, the evolution process of slope deformation was analyzed, especially the characteristics of basal heave deformation. The properties of the deep sliding zone soil in the slope were revealed by ring shear tests, which are suitable for studying the shear strength of soil that has experienced large shear displacements. Moreover, the residual strength parameters of the saturated sliding zone soil were applied to analyze the reserved thickness of the base. Results The results show that sliding zone soils exhibit obvious strain softening characteristics, which become more evident as the normal stress decreases. As the soil shear strength transitions from peak strength to residual strength, both the cohesion force and internal friction angle decrease, with the cohesion force decreasing to a greater extent than the internal friction angle. The residual cohesion force of sliding zone soil varies slightly with the shear rate, while the relationship between the residual internal friction angle and shear rate varies as a logarithmic function. When the shear rate is less than 2 mm/min, the residual shear strength parameter of sliding zone soil is more sensitive to the shear rate and vice versa. Conclusion Furthermore, according to the regression equations of the critical states of slope stability, the reserved thickness of the base under different slope rates was divided into four zones: A (extremely unstable zone), B (unstable zone), C (basically stable zone) and D (stable zone), and based on this, the criterion and early warning model of the reserved thickness of the base for slope excavation were established.

Background Since the number of chronic disease patients is increasing, relevant prevention and treatment services have become important long-term tasks for primary care institutions. However, problems in the provision of primary care services seriously affect the perception of such services in residents, especially chronic disease patients. Objective To understand chronic disease patients' assessment of the quality of primary care services, providing evidence for improving the quality of chronic disease management services in primary care. Methods A survey was conducted between July and August, 2020 with chronic disease patients (n=630) selected from primary care settings in Guangdong's Chaozhou by use of multistage stratified random sampling. The Primary Care Assessment Tool-Adult Simplified Version (PCAT-AS) (consists of 10 domains, including first contact accessibility, coordination, ongoing, comprehensiveness, community orientation and other 5 domains) was used in the survey for understanding chronic disease patients' assessment of the quality of primary care services. Multiple linear regression was adopted to identify factors potentially associated with the PCAT-AS score. Results Altogether, 553 cases (87.8%) who returned responsive questionnaires were enrolled for analysis. The average total PCAT-AS score for all respondents was (95.88±13.44) . The top three domains ranked in terms of average standardized score were comprehensiveness (services needed) (7.89) , first contact accessibility (7.72) , and first contact utilization (7.58) , and the bottom three-ranked domains were coordination (referrals) (5.61) , community orientation (6.11) and patient and family centeredness (6.40) . Multiple linear regression analysis indicated that higher total PCAT-AS score was associated with living in urban areas in contrast to rural areas〔b (95%CI) =-6.983 (-10.598, -3.368) 〕, senior high school and higher education level instead of junior high school and lower education level〔b (95%CI) =4.046 (0.966, 7.125) 〕, permanent residents without the local hukou in contrast to those with local hukou〔b (95%CI) =-5.360 (-9.517, -1.202) 〕, good self-rated health instead of relatively poor self-rated health〔b (95%CI) =-4.962 (-8.438, -1.486) 〕 or poor self-rated health〔b (95%CI) =-7.787 (-12.789, -2.786) 〕, having a contracted family doctor instead of having no contracted family doctor〔b (95%CI) =4.686 (2.508, 6.865) 〕, first choosing a community health center for treating common diseases instead of a village clinic〔b (95%CI) =-5.865 (-9.951, -1.779) 〕 or a district/county-level hospital or tertiary hospital〔b (95%CI) =-6.061 (-11.330, -0.792) 〕, 4-6 primary care visits instead of 1-3 primary care visits〔b (95%CI) =5.876 (3.367, 8.384) or 7 or more primary care visits instead of 1-3 primary care visits〔b (95%CI) =9.045 (6.512, 11.579) 〕, and high satisfaction with primary care services instead of fair satisfaction〔b (95%CI) =-2.844 (-4.817, -0.870) 〕 or dissatisfaction〔b (95%CI) =-10.418 (-17.050, -3.786) 〕. Conclusion Overall, Chaozhou chronic disease patients reported a sound level of treatment experience in primary care. Specifically, they reported good primary care experience in three domains, including comprehensiveness, first contact accessibility and first contact utilization, but poor experience in community orientation, and coordination (including information systems and referrals) . However, urban patients reported better primary care experience than rural patients. So continued efforts are needed to strengthen primary care performance in rural areas.