Numerical analysis of downward progressive landslides in long natural slopes with sensitive clay

Landslides occurring in sensitive clay often result in widespread destruction,posing a significant risk to human lives and property due to the substantial decrease in undrained shear strength during deformation.Assessing the consequences of these landslides is challenging and necessitates robust numerical methods to comprehensively investigate their failure mechanisms.While studies have extensively explored upward progressive landslides in sensitive clays,understanding downward progressive cases remains limited.In this study,we utilised the nodal integration-based particle finite element method(NPFEM)with a nonlinear strain-softening model to analyse downward progressive landslides in sensitive clay on elongated slopes,induced by surcharge loads near the crest.We focused on elucidating the underlying failure mechanisms and evaluating the effects of different soil parameters and strainsoftening characteristics.The simulation results revealed the typical pattern for downward landslides,which typically start with a localised failure in proximity to the surcharge loads,followed by a combination of different types of failure mechanisms,including single flow slides,translational progressive landslides,progressive flow slides,and spread failures.Additionally,inclined shear bands occur within spread failures,often adopting distinctive ploughing patterns characterised by triangular shapes.The sensitive clay thickness at the base,the clay strength gradient,the sensitivity,and the softening rate significantly influence the failure mechanisms and the extent of diffused displacement.Remarkably,some of these effects mirror those observed in upward progressive landslides,underscoring the interconnectedness of these phenomena.This study contributes valuable insights into the complex dynamics of sensitive clay landslides,shedding light on the intricate interplay of factors governing their behaviour and progression.

Scutellarin alleviates liver injury in type 2 diabetic mellitus by suppressing hepatocyte apoptosis in vitro and in vivo

Objective: Scutellarin is a primary active composition come from Erigeron breviscapus. It is well known that scutellarin has anti-infammatory and antioxidant physiological functions. In this study, we detected the effects of scutellarin on hepatocyte cell apoptosis in type 2 diabetes mellitus(T2DM) rats.Methods: Sprague Dawley(SD)(6–8 weeks, 160–180 g) rats were randomly divided into six groups: control, model, scutellarin low-dose, medium-dose, high-dose treatment, and rosiglitazone positive groups;with 10 SD rats in each group(n = 10). The changes of biochemical factors in serum were detected by automatic biochemical instrument, the pathological changes of liver tissue were detected by hematoxylin and eosin(HE) staining, the apoptosis of liver tissue and cells was detected by tissue staining and fow analyzer, and the expression of apoptosis-related factors were determined by q PCR, Western blot and immunohistochemistry in liver tissues or cells.Results: The results showed that scutellarin decreased the levels of fasting blood glucose, total cholesterol, triglyceride, and low-density lipoprotein and increased the levels of high-density lipoprotein.Meanwhile, scutellarin decreased the levels of alanine transaminase(ALT) and aspartate transaminase(AST) and improved liver function. In addition, scutellarin suppressed the secretion of interleukin-1(IL-1), interleukin-6(IL-6) and tumor necrosis factor-a(TNF-a) and reduced hepatocyte apoptosis.Furthermore, scutellarin inhibited the expression of cleaved Caspase-3, Bax, and cytochrome C(Cyt-C)and promoted the expression of Bcl-2.Conclusion: Scutellarin can inhibit the apoptotic pathway, thereby relieving T2DM.