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Abstract The U.S. water supply and carbon sequestration are increasingly threatened by future climate change and air pollution. This study investigates the ecohydrological responses to the individual and combined impacts of climate change and anthropogenic emission (referring only to air pollutants, excluding greenhouse gases) changes at two spatial scales by coupling a regional online‐coupled meteorology and chemistry model (WRF‐Chem) and a water balance model (WaSSI). Combined effects of climate change and anthropogenic emission changes in 2046–2055 relative to 2001–2010 over the US enhance hydrological cycle and carbon sequestration. However, a drying trend occurs in the central and part of the western U.S. Climate change is projected to dominate the ecohydrological changes in most regions. Anthropogenic emission changes under 2001–2010 climate conditions cools down inland water resource regions with 0.01–0.15°C, moisturizes the east and dry the west U.S. More stringent anthropogenic emission control enhances precipitation and ecosystem production in the east and west but has an opposite trend in the central U.S. The ecohydrological modeling in California and North Carolina based on 4‐km resolution meteorological data in 2050 and 2005 shows varying changes in magnitudes and spatial patterns compared to results based on 36‐km resolution meteorological data. Projected changes in air pollutant emissions may accelerate climatic warming in coastal areas and the state of New Mexico and decrease precipitation, runoff, and carbon sequestration in part of the western U.S. Strategies to address future possible problems such as heatwaves, water stress, and ecosystem productivity should consider the varying interplay between air quality control and climate change at different spatial scales. 

Emerging wearable devices are very attractive and promising in biomedical and healthcare fields because of their biocompatibility for monitoring in situ biomarker-associated signals and external stimulus. Many such devices or systems demand microscale sensors fabricated on curved and flexible hydrogel substrates. However, fabrication of microstructures on such substrates is still challenging because the traditional planar lithography process is not compatible with curved, flexible, and hydrated substrates. Here, we present a shadow-mask-assisted deposition process capable of directly generating metallic microstructures on the curved hydrogel substrate, specifically the contact lens, one of the most popular hydrogel substrates for wearable biomedical applications. In this process, the curved hydrogel substrate is temporarily flattened on a planar surface and metal features are deposited on this substrate through a shadow mask. To achieve a high patterning fidelity, we have experimentally and theoretically investigated various types of distortion due to wrinkles on 3D-printed sample holders, geometric distortion of the substrate due to the flattening process, and volume change of the hydrogel material during the dehydration and hydration processes of the contact lens. Using this method, we have demonstrated fabrication of various titanium pattern arrays on contact lenses with high fidelity and yield. 

Abstract Ultrafast movements propelled by springs and released by latches are thought limited to energetic adjustments prior to movement, and seemingly cannot adjust once movement begins. Even so, across the tree of life, ultrafast organisms navigate dynamic environments and generate a range of movements, suggesting unrecognized capabilities for control. We develop a framework of control pathways leveraging the non-linear dynamics of spring-propelled, latch-released systems. We analytically model spring dynamics and develop reduced-parameter models of latch dynamics to quantify how they can be tuned internally or through changing external environments. Using Lagrangian mechanics, we test feedforward and feedback control implementation via spring and latch dynamics. We establish through empirically-informed modeling that ultrafast movement can be controllably varied during latch release and spring propulsion. A deeper understanding of the interconnection between multiple control pathways, and the tunability of each control pathway, in ultrafast biomechanical systems presented here has the potential to expand the capabilities of synthetic ultra-fast systems and provides a new framework to understand the behaviors of fast organisms subject to perturbations and environmental non-idealities.