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  1. Free, publicly-accessible full text available September 1, 2024
  2. The hazard from earthquake-generated tsunami waves is not only determined by the earthquake’s magnitude and mechanisms, and distance to the earthquake area, but also by the geomorphology of the nearshore and onshore areas, which can change over time. In coastal hazard assessments, a changing coastal environment is commonly taken into account by increasing the sea-level to projected values (static). However, sea-level changes and other climate-change impacts influence the entire coastal system causing morphological changes near- and onshore (dynamic). We compare the run-up of the same suite of earthquake-generated tsunamis to a barrier island-marsh-lagoon-marsh system for statically adjusted and dynamically adjusted sea level and bathymetry. Sea-level projections from 2000 to 2100 are considered. The dynamical adjustment is based on a morphokinetic model that incorporates sea-level along with other climate-change impacts. We employ Representative Concentration Pathways 2.6 and 8.5 without and with treatment of Antarctic Ice-sheet processes (known as K14 and K17) as different sea-level projections. It is important to note that we do not account for the occurrence probability of the earthquakes. Our results indicate that the tsunami run-up hazard for the dynamic case is approximately three times larger than for the static case. Furthermore, we show that nonlinear and complex responses of the barrier island-marsh-lagoon-marsh system to climate change profoundly impacts the tsunami hazard, and we caution that the tsunami run-up is sensitive to climate-change impacts that are less well-studied than sea-level rise. 
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  3. Ataxia-telangiectasia mutated (ATM) is one of the three main apical kinases at the crux of DNA damage response and repair in mammalian cells. ATM activates a cascade of downstream effector proteins to regulate DNA repair and cell cycle checkpoints in response to DNA double-strand breaks. While ATM is predominantly known for its role in DNA damage response and repair, new roles of ATM have recently begun to emerge, such as in regulating oxidative stress or metabolic pathways. Here, we report the surprising discovery that ATM inhibition and deletion lead to reduced expression of the nuclear envelope protein lamin A. Lamins are nuclear intermediate filaments that modulate nuclear shape, structure, and stiffness. Accordingly, inhibition or deletion of ATM resulted in increased nuclear deformability and enhanced cell migration through confined spaces, which requires substantial nuclear deformation. These findings point to a novel connection between ATM and lamin A and may have broad implications for cells with ATM mutations—as found in patients suffering from Ataxia Telangiectasia and many human cancers—which could lead to enhanced cell migration and increased metastatic potential. 
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  4. Abstract

    Real‐time tsunami prediction is necessary for tsunami forecasting. Although tsunami forecasting based on a precomputed tsunami simulation database is fast, it is difficult to respond to earthquakes that are not in the database. As the computation speed increases, various alternatives based on physics‐based models have been proposed. However, physics‐based models still require several minutes to simulate tsunamis and can have numerical stability issues that potentially make them unreliable for use in forecasting—particularly in the case of near‐field tsunamis. This paper presents a data‐driven model called the tsunami runup response function for finite faults (TRRF‐FF) model that can predict alongshore near‐field tsunami runup distribution from heterogeneous earthquake slip distribution in less than a second. Once the TRRF‐FF model is trained and calibrated based on a discrete set of tsunami simulations, the TRRF‐FF model can predict alongshore tsunami runup distribution from any combination of finite fault parameters. The TRRF‐FF model treats the leading‐order contribution and the residual part of the alongshore tsunami runup distribution separately. The interaction between finite faults is modeled based on the leading‐order alongshore tsunami runup distribution. We validated the TRRF‐FF modeling approach with more than 200 synthetic tsunami scenarios in eastern Japan. We further explored the performance of the TRRF‐FF model by applying it to the 2011 Tohoku (Japan) tsunami event. The results show that the TRRF‐FF model is more flexible, occupies much less storage space than a precomputed tsunami simulation database, and is more rapid and reliable than real‐time physics‐based numerical simulation.

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  5. Abstract

    A continuum damage model was developed to describe the finite tensile deformation of tough double‐network (DN) hydrogels synthesized by polymerization of a water‐soluble monomer inside a highly crosslinked rigid polyelectrolyte network. Damage evolution in DN hydrogels was characterized by performing loading‐unloading tensile tests and oscillatory shear rheometry on DN hydrogels synthesized from 3‐sulfopropyl acrylate potassium salt (SAPS) and acrylamide (AAm). The model can explain all the mechanical features of finite tensile deformation of DN hydrogels, including idealized Mullins effect and permanent set observed after unloading, qualitatively and quantitatively. The constitutive equation can describe the finite elasto‐plastic tensile behavior of DN hydrogels without resorting to a yield function. It was showed that tensile mechanics of DN hydrogels in the model is controlled by two material parameters which are related to the elastic moduli of first and second networks. In effect, the ratio of these two parameters is a dimensionless number that controls the behavior of material. The model can capture the stable branch of material response during neck propagation where engineering stress becomes constant. Consistent with experimental data, by increasing the elastic modulus of the second network the finite tensile behavior of the DN hydrogel changes from necking to strain hardening.

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  6. null (Ed.)
    Halogen-bonded (XB) complexes between halide anions and a cyclopropenylium-based anionic XB donor were characterized in solution for the first time. Spontaneous formation of such complexes confirms that halogen bonding is sufficiently strong to overcome electrostatic repulsion between two anions. The formation constants of such “anti-electrostatic” associations are comparable to those formed by halides with neutral halogenated electrophiles. However, while the latter usually show charge-transfer absorption bands, the UV-Vis spectra of the anion–anion complexes examined herein are determined by the electronic excitations within the XB donor. The identification of XB anion–anion complexes substantially extends the range of the feasible XB systems, and it provides vital information for the discussion of the nature of this interaction. 
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