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The impact of geohazards on mountainous settlement have been focused in recent years. Despite the booming development in the modeling of hazards and vulnerability, the risk assessment in mountainous area still have difficulty in absence of refined data. Moreover, development imbalances widely exist in mountainous areas, which ignored in previous researches. In this study, the development imbalances were quantified and integrated into risk assessment framework, which be applied in Lushan and Baoxing mountainous areas. The refined distribution of soc-economic data is obtained by using spatialization from the census, which eases the situation of the lack of data. Then, a frequency ratio-random forest (FR-RF) model is conducted to evaluate the geohazards hazard. Meanwhile, vulnerability was evaluated using triangular fuzzy number‑based analytic hierarchy process (TFN-AHP). In vulnerability assessment, the inhomogeneity index is integrated to evaluate the imbalance between indicators, the use of which can reward a more realistic vulnerability result. Finally, risk map was produced by multiplying hazard and vulnerability. The risk assessment framework is successfully applied in Lushan and Baoxing counties of Southwestern China, which is a typical mountainous area with frequent earthquakes, uneven development, and a lack of high-precision data. The total area of high and extremely high hazard (868.82 km2), vulnerability (258.66 km2), and risk (113.49 km2) are estimated and mapped.

The upper reaches of Min River (The upper Min River) is located in Southwest China with significant mountain settlements, which are vulnerable to frequent geological hazards. Based on a field investigation, collation of yearbook data, and analysis through the use of SPSS statistical software, a vulnerability evaluation index system of geological hazards was devised. According to the actual field situation and the acquired data of the study area in 2006, 2009, and 2015, 16 indicators were selected as settlement vulnerability evaluation indexes of geological hazards. The indexes included population density, building coverage, and economic density. Based on the comprehensive evaluation model of entropy value, the dynamic change in the settlement vulnerability of geological hazards was analyzed. The results showed that population density, building coverage, economic density, and road density were the factors that affected the settlement vulnerability of geological hazards the most—Wenchuan earthquake caused considerable damage to the upper Min River, making the area the most vulnerable in 2009. However, its vulnerability decreased in 2015, which indicated that postearthquake reconstruction achieved significant results. Thus, the vulnerability has emerged as an important indicator reflecting the safety and healthy development of mountain settlements.

The development and outbursts of glacial lake debris flow pose threats to downstream infrastructures. Thus, rational assessment of its potential hazards is necessary to mitigate geological hazards along the Sichuan–Tibet railway lines. In this paper, we used logistic regression models and Rapid Mass Movement Simulation methods to assess the multiyear dynamic evolutionary characteristics and outburst risks of the glacial lake and to conduct numerical simulation of the debris flow process. The adopted methodology used remote sensing images from the Landsat 1-Landsat 8 series for the period 1973–2018, combined with the pieces of information of the geological expedition in the glacial lake Dongcuoqu, Luolong County, Tibet, China. The results revealed that the probability of collapse risk of the Dongcuoqu glacial lake dam was 0.39, and its risk extent reached level I, which indicates medium hazardousness and severe loss. The debris flow process simulation comprises of four stages: initiation, acceleration, deceleration, and termination. The outburst floods flow through the proposed location of the Sichuan–Tibet railway. Specifically, the flow velocity in the vicinity of the Luolong station of nearly 5 m/s, which poses a significant threat to the safe construction of the railway. In the flood and non-flood periods, the change in the amount of snow and ice melt was distinctive, and the maximum storage capacities of the glacial lake during these periods were 82 × 106 m3 and 60.1 × 106 m3, respectively. These findings suggest that the assessment results can be used as an excellent reference for the reduction of the construction risk of the proposed Sichuan–Tibet railway under disaster stress in glacial lake outburst hazard areas.

Once urinary bladder cancer (UBC) develops into muscle-invasive bladder cancer, its mortality rate increases dramatically. However, the molecular mechanisms of UBC invasion and metastasis remain largely unknown. Herein, using 5637 UBC cells, we generated two sublines with low (5637 NMI) and high (5637 HMI) invasive capabilities. Mass spectrum analyses revealed that the Wnt family protein Wnt7a is more highly expressed in 5637 HMI cells than in 5637 NMI cells. We also found that increased Wnt7a expression is associated with UBC metastasis and predicted worse clinical outcome in UBC patients. Wnt7a depletion in 5637 HMI and T24 cells reduced UBC cell invasion and decreased levels of active β-catenin and its downstream target genes involved in the epithelial-to-mesenchymal transition (EMT) and extracellular matrix (ECM) degradation. Consistently, treating 5637 NMI and J82 cells with recombinant Wnt7a induced cell invasion, EMT, and expression of ECM degradation–associated genes. Moreover, TOP/FOPflash luciferase assays indicated that Wnt7a activated canonical β-catenin signaling in UBC cells, and increased Wnt7a expression was associated with nuclear β-catenin in UBC samples. Wnt7a ablation suppressed matrix metalloproteinase 10 (MMP10) expression, and Wnt7a overexpression increased MMP10 promoter activity through two TCF/LEF promoter sites, confirming that Wnt7a-mediated MMP10 activation is mediated by the canonical Wnt/β-catenin pathway. Of note, the microRNA miR-370-3p directly repressed Wnt7a expression and thereby suppressed UBC cell invasion, which was partially restored by Wnt7a overexpression. Our results have identified an miR-370-3p/Wnt7a axis that controls UBC invasion through canonical Wnt/β-catenin signaling, which may offer prognostic and therapeutic opportunities.