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In order to lower the risks of large-scale landslides and improve community resilience in Taiwan, a long-term project has been promoted by the Soil and Water Conservation Bureau since 2017. In this study, methods to build an emergency response framework including hazard mapping and early warning system establishment were introduced. For hazard mapping, large-scale landslides were categorized into a landslide, debris flow, or landslide dam type based on the movement of unstable materials and topography. Each disaster type has different hazard zone delineation methods to identify the affected areas. After establishing the possible effected areas, early warning mechanisms, including warning value using rainfall as the indicator and evacuation procedures, should be created for emergency response. To set the warning value, analysis of the occurrence thresholds of previous existing large-scale landslides was conducted to determine the critical rainfall and further utilized to set the warning value considering the evacuation time for the locals. Finally, for integration with the current debris flow emergency response system, potential large-scale landslide areas were further divided into two types based on their spatial relationship with debris flows. For those overlapping with existing debris flow protected targets, the current emergency response system was upgraded considering the impact of large-scale landslides, while the others were suggested for use in building a new emergency response procedure. This integrated framework could provide a feasible risk avoidance method for local government and residents.

The frequency of extreme rainfall corresponding with debris flows and large-scale landslides is increasing in the Taiwan. The traveling distance of debris flows get longer with increased sediment supply, and the hazard area is also larger than regular disaster situation. The debris flows can be considering as a mixture with solid phase and liquid phase. With a larger sediment supply in the dynamic process, the volume of fine sediment separating from solid phase is also larger, and so the state of liquid phase is change after fine sediment mix with water. This phenomenon contributes a significant effect on the mobility of debris flows and large- scale landslides. The composition of the mixture plays an important role in the analysis of the hazard area. In the present study, a two-dimensional numerical model is proposed to simulate the dynamic process of debris flows and landslides under different compositions of the mixture. The proposed was applied to simulate a case of extreme rainfall event, and the topographic data after disaster was used for verification. When the composition of the mixture included with fine sediment, the simulation of affected area had a good agreement with the real situation. The present study pointed out that the simulation of debris and landslide under extreme rainfall condition should consider the effect of fine sediment in the simulation condition.

Background: In the present study we assessed the protective effects of a pharmacological approach to stabilize the retromer complex in a PD mouse model. Missense mutations in the VPS35 gene are a rare cause of familial PD. The VPS35 protein is a subunit of the retromer cargo recognition complex and has a variety of functions within neurons, many of which are potentially relevant for the pathophysiology of PD. Prior studies have revealed a role for the retromer complex in controlling accumulation and clearance of α-synuclein aggregates. We previously identified an aminoguanidine hydrazone, 1,3 phenyl bis guanylhydrazone (compound 2a), as a pharmacological stabilizer of the retromer complex that increases retromer subunit protein levels and function., Methods: Here, we validate the efficacy of 2a in protecting against αSynuclein pathology and dopaminergic neuronal degeneration in a PD mouse model generated by unilateral injection of AAV-A53T-αSynuclein in the substantia nigra., Results: Daily intraperitoneal administration of 2a at 10 mg/Kg for 100 days led to robust protection against behavioral deficits, dopaminergic neuronal loss and loss of striatal dopaminergic fibers and striatal monoamines. Treatment with 2a activated αSynuclein degradation pathways in the SN and led to significant reductions in aggregates and pathological αSynuclein., Conclusion: These data suggest retromer stabilization as a promising therapeutic strategy for Parkinson's disease leading to neuroprotection of dopaminergic neurons and rescue in the accumulation of pathological and aggregates αSynuclein. We identified 2a compound as potential clinical drug candidate for future testing in Parkinson's disease patients., Competing Interests: Competing interests SE is co-inventor of the international patent #W02020201326A1 with the title: “Aminoguanidine hydrazones as retromer stabilizer useful for treating neurological diseases” that included compound 2a.