•A novel method is presented to measure the impact of pluvial flood on urban roads.•An inundation model is used to assess the risk of flood on urban road disturbance.•Pluvial flood leads to ...proportionate but nonlinear impact on road inundation risk.
Urban pluvial flood are attracting growing public concern due to rising intense precipitation and increasing consequences. Accurate risk assessment is critical to an efficient urban pluvial flood management, particularly in transportation sector. This paper describes an integrated methodology, which initially makes use of high resolution 2D inundation modeling and flood depth-dependent measure to evaluate the potential impact and risk of pluvial flash flood on road network in the city center of Shanghai, China. Intensity–Duration–Frequency relationships of Shanghai rainstorm and Chicago Design Storm are combined to generate ensemble rainfall scenarios. A hydrodynamic model (FloodMap-HydroInundation2D) is used to simulate overland flow and flood inundation for each scenario. Furthermore, road impact and risk assessment are respectively conducted by a new proposed algorithm and proxy. Results suggest that the flood response is a function of spatio-temporal distribution of precipitation and local characteristics (i.e. drainage and topography), and pluvial flash flood is found to lead to proportionate but nonlinear impact on intra-urban road inundation risk. The approach tested here would provide more detailed flood information for smart management of urban street network and may be applied to other big cities where road flood risk is evolving in the context of climate change and urbanization.
Nanofluidics derived from low‐dimensional nanosheets and protein nanochannels are crucial for advanced catalysis, sensing, and separation. However, polymer nanofluidics is halted by complicated ...preparation and miniaturized sizes. This work reports the bottom‐up synthesis of modular nanofluidics by confined growth of ultrathin metal–organic frameworks (MOFs) in a polymer membrane consisting of zwitterionic dopamine nanoparticles (ZNPs). The confined growth of the MOFs on the ZNPs reduces the chain entanglement between the ZNPs, leading to stiff interfacial channels enhancing the nanofluidic transport of water molecules through the membrane. As such, the water permeability and solute selectivity of MOF@ZNPM are one magnitude improved, leading to a record‐high performance among all polymer nanofiltration membranes. Both the experimental work and the molecular dynamics simulations confirm that the water transport is shifted from high‐friction‐resistance conventional viscous flow to ultrafast nanofluidic flow as a result of rigid and continuous nanochannels in MOF@ZNPM.
A rigid‐scaffold‐reinforced polymeric nanoparticles’ interfacial channel strategy is proposed for fabricating nanofluidic membranes that exhibit water permeance and dye/salt selectivity that are 1–2 orders of magnitude higher than conventional polymeric membranes. The unprecedented separation performance is due to the paradigm shift of water transport from conventional viscous flow to ultrafast nanofluidic flow in the membrane nanofluidics.
Improving the antibacterial activity of H2O2 and reducing its usage are requirements for wound disinfection. Nanomaterials with intrinsic peroxidase‐like properties are developed to enhance the ...antibacterial performance of H2O2 and avoid the toxicity seen with high H2O2 levels. Here, Pd–Pt core–frame nanodendrites consist of a dense array of platinum (Pt) branches on a Pd core are synthesized, and subsequently converted to Pt hollow nanodendrites by selective removal of the Pd cores by wet etching. The fabricated Pt hollow nanodendrites exert striking peroxidase‐like activity due to the maximized utilization efficiency of the Pt atoms and the presence of high‐index facets on their surfaces. By catalyzing the decomposition of H2O2 into more toxic hydroxyl radicals (•OH), Pt hollow nanodendrites exhibit excellent bactericidal activity against both Gram‐negative and Gram‐positive bacteria with the assistance of low concentrations of H2O2. Furthermore, Pt hollow nanodendrites accelerate wound healing in the presence of low doses of H2O2. In addition, no obvious adverse effects are observed at the given dose of nanodendrites. These findings can be used to guide the design of noble metal‐based nanomaterials as potential enzyme‐mimetic systems and advance the development of nanoenzymes to potentiate the antibacterial activity of H2O2.
Platinum (Pt) hollow nanodendrites are fabricated, which exert striking peroxidase‐like activity due to the maximized efficiency of Pt atoms and the presence of high‐index facets. By catalyzing the decomposition of H2O2 into more toxic •OH, Pt hollow nanodendrites show excellent bactericidal activity with the assistance of low concentrations of H2O2 and potently accelerated wound healing in actual wound infections.
In this paper, we describe a new method of modeling coastal inundation arising from storm surge by coupling a widely used storm surge model (ADCIRC) and an urban flood inundation model (FloodMap). ...This is the first time the coupling of such models is implemented and tested using real events. The method offers a flexible and efficient procedure for applying detailed ADCIRC storm surge modeling results along the coastal boundary (with typical resolution of ∼100 m) to FloodMap for fine resolution inundation modeling (<5 m). The coastal inundation during Hurricane Sandy was simulated at both the city (New York City) and subregional (lower Manhattan) scales with various resolutions. Results obtained from the ADCIRC and coupled ADCIRC‐FloodMap simulations were compared with the recorded (high water marks) and derived (inundation extent based on the planar method) data from FEMA. At the city scale, coupled ADCIRC‐FloodMap modeling demonstrates improved prediction over ADCIRC modeling alone for both the extent and depth of inundation. The advantage of the coupled model is further illustrated in the subregional modeling, using a mesh resolution of 3 m which is substantially finer than the inland mesh resolution used by ADCIRC (>70 m). In further testing, we explored the effects of mesh resolution and roughness specification. Results agree with previous studies that fine resolution is essential for capturing intricate flow paths and connectivity in urban topography. While the specification of roughness is more challenging for urban environments, it may be empirically optimized. The successful coupling of ADCIRC and FloodMap models for fine resolution coastal inundation modeling unlocks the potential for undertaking large numbers of probabilistically based synthetic surge events for street‐level risk analysis.
Key Points
We coupled a storm surge model (ADCIRC) with a 2‐D flood inundation model (FloodMap)
We evaluated the model performance at the city level and district level
The approach unlocks the potential for fine resolution coastal flood modelling driven by storm surge
A dynamic surface pattern with a topography and fluorescence in response to environmental stimulus can enable information recording, hiding, and reading. Such patterns are therefore widely used in ...information security and anticounterfeiting. Here, we demonstrate a dynamic dual pattern using a supramolecular network comprising a copolymer containing pyridine (P4VP-nBA-S) and hydroxyl distyrylpyridine (DSP-OH) as the skin layer for bilayer wrinkling systems, in which both the wrinkle morphology and fluorescence color can be simultaneously regulated by visible light-triggered isomerization of DSP-OH, or acids. Acid-induced protonation of pyridines can dynamically regulate the cross-linking of the skin layer through hydrogen bonding, and the fluorescence of DSP-OH. On selective irradiation with 450 nm visible light or acid treatment, the resulting hierarchical patterned surface becomes smooth and wrinkled reversibly, and simultaneously its fluorescence changes dynamically from blue to orange-red. The smart surfaces with dynamic hierarchical wrinkles and fluorescence can find potential application in anticounterfeiting.
Recent studies suggest that in humans, DNA sequences responsible for protein coding regions comprise only 2% of the total genome. The rest of the transcripts result in RNA transcripts without ...protein-coding ability, including long noncoding RNAs (lncRNAs). Different from most members in the lncRNA family, the metastasis-associated lung adenocarcinoma transcript 1 (Malat1) is abundantly expressed and evolutionarily conserved throughout various mammalian species. Malat1 is one of the first identified lncRNAs associated with human disease, and cumulative studies have indicated that Malat1 plays critical roles in the development and progression of various cancers. Malat1 is also actively involved in various physiologic processes, including alternative splicing, epigenetic modification of gene expression, synapse formation, and myogenesis. Furthermore, extensive evidences show that Malat1 plays pivotal roles in multiple pathological conditions as well. In this review, we will summarize latest findings related to the physiologic and pathophysiological processes of Malat1 and discuss its therapeutic potentials.
Abstract
Metal–organic frameworks (MOFs) are highly versatile materials that have been identified as promising candidates for membrane‐based gas separation applications due to their uniformly narrow ...pore windows and virtually unlimited structural and chemical features. Defect engineering of MOFs has opened new opportunities for manipulating MOF structures, providing a simple yet efficient approach for enhancing membrane separation. However, the utilization of this strategy to tailor membrane microstructures and enhance separation performance is still in its infancy. Thus, this summary aims to provide a guideline for tailoring defective MOF‐based membranes. Recent developments in defect engineering of MOF‐based membranes will be discussed, including the synthesis strategies for defective MOFs, the effects of defects on the gas adsorption properties, gas transport mechanisms, and recently reported defective MOF‐based membranes. Furthermore, the emerging challenges and future prospects will be outlined. Overall, defect engineering offers an exciting opportunity to improve the performance of MOF‐based gas membranes. However, there is still a long way to go to fully understand the influence of defects on MOF properties and optimize the design of MOF‐based membranes for specific gas separation applications. Nonetheless, continued research in this field holds great promise for the development of next‐generation membrane‐based gas separation technologies.
Snap‐through bistability is often observed in nature (e.g., fast snapping to closure of Venus flytrap) and the life (e.g., bottle caps and hair clippers). Recently, harnessing bistability and ...multistability in different structures and soft materials has attracted growing interest for high‐performance soft actuators and soft robots. They have demonstrated broad and unique applications in high‐speed locomotion on land and under water, adaptive sensing and fast grasping, shape reconfiguration, electronics‐free controls with a single input, and logic computation. Here, an overview of integrating bistable and multistable structures with soft actuating materials for diverse soft actuators and soft/flexible robots is given. The mechanics‐guided structural design principles for five categories of basic bistable elements from 1D to 3D (i.e., constrained beams, curved plates, dome shells, compliant mechanisms of linkages with flexible hinges and deformable origami, and balloon structures) are first presented, alongside brief discussions of typical soft actuating materials (i.e., fluidic elastomers and stimuli‐responsive materials such as electro‐, photo‐, thermo‐, magnetic‐, and hydro‐responsive polymers). Following that, integrating these soft materials with each category of bistable elements for soft bistable and multistable actuators and their diverse robotic applications are discussed. To conclude, perspectives on the challenges and opportunities in this emerging field are considered.
Harnessing bistability and multistability for creating varieties of high‐performance soft robots has attracted increasing interest in soft robotics. This paper presents a comprehensive review of integrating representative bistable and multistable structures with soft materials under different actuations in soft actuators for diverse robotic functionalities, as well as, theoretical guidance on structural designs and materials selection for target robotic tasks.
Mixed matrix membranes (MMMs), conjugating the advantages of flexible processing‐ability of polymers and high‐speed mass transfer of porous fillers, are recognized as the next‐generation ...high‐performance CO2 capture membranes for solving the current global climate challenge. However, controlling the crystallization of porous metal‐organic frameworks (MOFs) and thus the close stacking of MOF nanocrystals in the confined polymer matrix is still undoable, which thus cannot fully utilize the superior transport attribute of MOF channels. In this study, the “confined swelling coupled solvent‐controlled crystallization” strategy is employed for well‐tailoring the in‐situ crystallization of MOF nanocrystals, realizing rapid (<5 min) construction of defect‐free freeway channels for CO2 transportation in MMMs due to the close stacking of MOF nanocrystals. Consequently, the fabricated MMMs exhibit approximately fourfold enhancement in CO2 permeability, i.e., 2490 Barrer with a CO2/N2 selectivity of 37, distinctive antiplasticization merit, as well as long‐term running stability, which is at top‐tier level, enabling the large‐scale manufacture of high‐performance MMMs for gas separation.
A facile and efficient “confined swelling coupled solvent‐controlled crystallization” strategy is demonstrated to control the in situ crystallization of metal‐organic frameworks nanocrystals in polyethylene oxide membranes, realizing rapid construction of defect‐free freeway channels for CO2 transportation in mixed matrix membranes (MMMs). The optimized MMM showed fourfold enhancement in CO2 permeability, i.e., 2705 Barrer, with a CO2/N2 selectivity of 37.
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