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[1] Our ability to predict complex environmental fluid flow and transport hinges on accurate and efficient simulations of multiple physical phenomenon operating simultaneously over a wide range of spatial and temporal scales, including overbank floods, coastal storm surge events, drying and wetting bed conditions, and simultaneous bed form evolution. This research implements a fully coupled strategy for solving shallow water hydrodynamics, sediment transport, and morphological bed evolution in rivers and floodplains (PIHM_Hydro) and applies the model to field and laboratory experiments that cover a wide range of spatial and temporal scales. The model uses a standard upwind finite volume method and Roe's approximate Riemann solver for unstructured grids. A multidimensional linear reconstruction and slope limiter are implemented, achieving second-order spatial accuracy. Model efficiency and stability are treated using an explicit-implicit method for temporal discretization with operator splitting. Laboratory-and field-scale experiments were compiled where coupled processes across a range of scales were observed and where higherorder spatial and temporal accuracy might be needed for accurate and efficient solutions. These experiments demonstrate the ability of the fully coupled strategy in capturing dynamics of field-scale flood waves and small-scale drying-wetting processes.Citation: Li, S., and C. J. Duffy (2011), Fully coupled approach to modeling shallow water flow, sediment transport, and bed evolution in rivers, Water Resour. Res., 47, W03508,

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Abstract. The RMS US inland flood model provides flood hazard data of up to 10x10m resolution for the Contiguous United States for different return periods. The flood maps were developed using a series of physically based models. First, several thousand years of precipitation were simulated using principal component analysis coupled to a tropical cyclone precipitation model. Then, discharge and runoff were calculated using a semi-distributed rainfall runoff and routing model based on the TOPMODEL approach run at an hourly time step. This in turn forms the input to the fluvial and pluvial inundation models, which uses the shallow water equation to simulate flood propagation. Each of the individual model components such as precipitation, discharge and flood extent and depth were validated individually. The model generally performed very well compared to available flood maps, especially in the high exposure areas, even if it has some difficulties in the dry low exposure areas of the United States, which are heavily influenced by water management. The flood maps will be the base for the fully probabilistic loss model including a financial model. Via the simulated Hurricane track data set the flood model will be coupled to the RMS North Atlantic Hurricane model.

Autophagy is an evolutionarily ancient process wherein cells are able to break down intracellular contents in order to support normal physiology and development. Autophagosome formation is regulated by several different proteins, including the key cysteine protease Atg4. The contribution of Atg4 protein in the pathogenic fungus Cryphonectria parasitica, which causes blight in chestnut plants, has not been completely understood. In this context, we aimed to investigate the role of Atg4 during autophagy formation and their contribution with non-autophagic events in C. parasitica. By complementation assay, we determined that the CpAtg4 gene from C. parasitica was able to functionally complement the deletion of yeast Atg4. Using a yeast two-hybrid assay system, we confirmed that CpAtg4 and CpAtg8 directly interact with one another, and amino acids 377-409 of CpAtg4 were identified as being responsible for its binding with CpAtg8. The deletion mutant of CpAtg4 did not demonstrate positive monodansylcadaverine (MDC) staining, which indicated that CpAtg4 is required for autophagy in C. parasitica. Moreover, the ΔCpAtg4 strain exhibited a decrease in aerial hyphae formation and sporulation, and reduction in virulence on apple and chestnut stem. The ΔCpAtg4 strains were also more sensitive to H2O2- and Congo red-induced stress. We further determined that amino acids 377-409 of CpAtg4 were essential for the function of CpAtg4 in vivo. Together, our findings indicated that CpAtg4 is required for the autophagy formation, fungal phenotypic traits, stress tolerance, and virulence in C. parasitica.