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In the Wuxia section of the Three Gorges Reservoir area, it is found that there are many deformation signs of sliding-bending along the bedding bank slope, and the cyclic fluctuation of reservoir water worsens the deterioration and instability of the bank leading edge. Taking Qingshi #6 slope in the Wuxia section as an example, an laboratory generalized model is constructed to study the catastrophe mechanism of bedding limestone bank slope under the deterioration of rock mass in hydro-fluctuation belt. The research shows that: the bank slope is in a stable state as a whole for a long time before impoundment. After impoundment, with the deterioration aggravation of rock mass, the bank slope deformation intensifies until buckling failure. The deterioration of rock mass shortens the instability process of ‘deterioration-buckling’. Kinematic analysis shows that the peak velocity of the same rock stratum is similar during buckling failure. The movement characteristics of the rear part of the ‘buckling point’ of rock mass are relatively consistent, but the front part is relatively discrete. The buckling failure is the turning point and apex of bank slope energy release. Both displacement and stress show signs of premature failure after gradually increasing with deterioration evolution. The stress produces ‘concentration-release’ around the buckling failure. On the whole, the stress variation is earlier than the displacement variation, indicating that the stress monitoring is more effective. The core of stress monitoring is to determine the ‘key section’. For the ‘deterioration-buckling’ bank slope, the sharp increase of stress at the ‘deflection section’ of the front edge can be an important characterization of the critical instability of the bank slope. The trailing edge pushing always exists in the evolution process of ‘deterioration buckling’, which is the premise of bank slope catastrophe failure. However, the dominant factor of bank slope instability is the continuous deterioration of the rock mass in the hydro-fluctuation belt. The Qingshi #6 slope is currently in the process of evolution toward ‘strong bending uplift’, it may gradually evolve from a stable/basically stable state to an understable state, due to the continuous deterioration of the rock mass in the hydro-fluctuation belt.

Background: China is one of the countries that set the goal to eliminate mother-to-child transmission (EMTCT) of syphilis by a target date. Active screening for syphilis among pregnant women, followed by effective treatment of maternal syphilis, is critical for achieving the goal. The China health authority issued national implementation protocols to guide EMTCT practice in health facilities. Methods: Within a cohort of infants born to mothers infected with syphilis, we obtained the data of regimens used for treatment of maternal syphilis from the National Information System of Prevention of Mother-to-Child Transmission of HIV, Syphilis and Hepatitis B, and analysed the physician's treatment behaviour and its associated factors in a public hospital in Suzhou of China. Results: A total of 450 pregnant women who were positive for treponemal or non-treponemal antibody, or had previous infection with syphilis were included into the study for analysis. Of them, 260 (57.8%) were positive for both treponemal and non-treponemal antibodies (syphilis seropositivity), and 353 (78.4%) were treated for syphilis according to the protocol in which 123 (34.8%) were treated with two courses. Non-adherence to treatment recommended by the protocol for maternal syphilis was significantly associated with antenatal visits in the third trimester (AOR 6.65, 95% CI 2.20–20.07, P = 0.001), being positive only for a treponemal test (AOR 5.34, 95% CI 3.07–9.29, P < 0.001) or having a syphilis infection before the pregnancy (AOR 2.05, 95% CI 1.14–3.69, P = 0.017), whereas the uptake of treatment for two treatment courses was associated with attending antenatal care in 2020 or before (AOR 3.49, 95% CI 1.89–6.42, P < 0.001), being positive for treponemal and non-treponemal tests (AOR 5.28, 95% CI 2.78–10.06, P < 0.001) or having non-treponemal antibody titre of ≥1:8 (AOR 3.71, 95% CI 1.77–7.78, P = 0.001). Conclusions: Implementation of the current recommendation to offer a universal treatment for syphilis among all pregnant women who are shown to be positive for a treponemal test alone is challenging in some clinical settings in China. To meet the WHO goals for elimination of congenital syphilis by 2015, the Government of China incorporated a nationwide prevention of mother-to-child transmission program for HIV, syphilis and hepatitis B into the existing maternal and child healthcare system followed by issuing the Protocol for Prevention of Mother-to-Child Transmission of HIV, Syphilis and Hepatitis B in 2011, which was updated in 2015 and 2020. This study reported the adherence to the treatment recommendation for maternal syphilis in Suzhou, China. The findings have important implications for updating our knowledge on treatment of maternal syphilis for prevention of mother-to-child transmission of syphilis. [ABSTRACT FROM AUTHOR]

Ceftriaxone has been used to treat gonorrhea in China and most other countries for >1 decade, but the level of decreased susceptibility or clinical resistance to ceftriaxone has increased (1). [...]