Different concentrations of hyaluronic acid eye drops for dry eye syndrome: a systematic review and Meta-analysis.

AIM: To compare high or low concentration of hyaluronic acid eye drops (HY) for dry eye syndromes (DES). METHODS: Randomized controlled trials (RCTs) comparing various concentrations of HY were searched in PubMed, Embase, Web of Science, Cochrane, SinoMed, CNKI, Wanfang Database, CQVIP, and Chinese journals databases between inception and July 2023. Pooled standardized mean differences (SMD) or weighted mean difference (WMD) with 95% confidence intervals (CI) from RCTs evaluating Schirmer's I test (SIT), corneal fluorescein staining score (CFS), tear breakup time (TBUT), DES score (DESS), and Ocular Surface Disease Index (OSDI) were calculated. Sensitivity analysis, Egger's test and Meta-regression analysis were performed for all indicators. RESULTS: We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria, involving 1796 cases. High-concentrations group significantly improved the outcome of CFS according to random effects modelling (SMD, -3.37; 95%CI, -5.25 to -1.48; P=0.0005). The rest of the results were not statistically significant, including indicators such as SIT, TBUT, DESS and OSDI. CONCLUSION: For dry eyes with positive corneal staining, a high concentration of HY is recommended, whereas in other cases, a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes.

Lagged settlement in sandy cobble strata and earth pressure on shield tunnel.

Lagged settlement is a typical accident induced by shield construction in sandy cobble strata. This paper analyzed the process and mechanism of lagged settlement, results show that all phases are in accord with the characteristics of ellipsoid theory of particle flows. Based on this theory, a method for calculating coefficient of lateral earth pressure and loosened earth pressure is proposed in this research. For the coefficient of lateral earth pressure, the boundary of loosened ellipsoid is divided into two parts, the arch zone and the excavation zone, and the lateral pressure coefficients are derived respectively according to the stress state. For loosened earth pressure on tunnel, the Terzaghi earth pressure theory and Protodyakonov earth pressure theory are adapted in different conditions according to the state of loosened cobble soil. Theories developed in this study can be applied on determination of shield excavation parameters, as well as calculation of loosened earth pressure and control of tunnel support.

Equivalent deformation modulus of sandy pebble soil-Mathematical derivation and numerical simulation.

This study aims to investigate the mechanical properties of sandy pebble soil through theoretical deduction and finite element analysis. Based on the assumption of stress uniformity or strain uniformity, the analytical formulas for calculating the equivalent deformation modulus of pebble soil are derived through RVEs. To verify the accuracy of the formulas, a series of numerical experiments are conducted through ABAQUS. Results show that theoretical calculation values match numerical simulation results well and the analytical formulas are effective when the pebble content is 0-60%. For pebble content lower than 20%, the equivalent deformation modulus could be described by "Stress Uniformity Model". When content is 20%-60%, pebble soil is a transition state from "Stress Uniformity" to "Strain Uniformity", for which the constitutive model could be expressed as a modified transition formula. This research is helpful for further investigation of mechanical properties of pebble soil. The theories developed in this study can be used in determining shield excavation parameters, and predicting the ground settlement caused by shield excavation.

Three new lupane-type triterpenes from Ceriops tagal.

Three new lupane-type triterpenes, 3 alpha-O-trans-feruloylbetulinic acid (1), 3 alpha-O-trans-coumaroylbetulinic acid (2) and 3beta-O-cis-feruloylbetulin (3), together with 10 known triterpenes (4-13), were isolated from the aerial parts of the mangrove plant Ceriops tagal. The structures of the three new compounds were established by means of spectroscopic data analyses and chemical methods.

A new dolabrane-type diterpene from Ceriops tagal.

A new dolabrane-type diterpene named tagalsin O 1, together with six known analogues 2-7, were isolated from the aerial part of the mangrove plant Ceriops tagal. The structures and relative configurations were elucidated on the basis of their spectroscopic data. Cytotoxicity of the isolated compounds against HeLa human cervical carcinoma cancer cell line was evaluated.